A meeting of neurosurgeons and therapeutic neuroradiologists

Colloque organisé par Claudio Testa du 7 au 12 juin 1995

Participants

Alvaro Andreoli (Ospedale Bellaria, Bologna,Italy), Jean-Pierre Castel (Hôpital Pallegrin-Tripode, Bordeaux, France), Denise Gravenhof (Mayo Clinic, Rochester, Minnesota, USA), Robin Illingworth (Charing Cross Hospital, London, UK), Pierre Lasjaunias (CHU Bicêtre, secteur Paul-Broca, le Kremlin Bicêtre, France), Marco Leonardi (Ospedale Maggiore, Milano,Italy), Andrew Molyneux (The Radcliffe Infirmary, Oxford, UK), Jacques Moret (Fondation ophtalmologique Rotschild, Paris, France), Luc Picard (Hôpital Saint-Julien, Centre hospitalier universitaire, Nancy, France), Bernd Richling (Universitatsklinik, Vienna, Austria), Peter Schmiedek (Ruprecht-Karls-Universität Heidelberg, Mannheim, Germany), Istvan Szikora (National Institute of Neurosurgery, Budapest, Hungary), Claudio Testa (Ospedale Bellaria, Bologna, Italy), Claudio Trevisan (Ospedale Bellaria, Bologna, Italy), Janos Vajda (National Institute of Neurosurgery, Budapest, Hungary), Roberto Villani (Ospedale Policlinico, Milano, Italy), David Wiebers (Mayo Clinic, Rochester, Minnesota, USA)

Compte-rendu

One year ago, the French Fondation des Treilles asked Claudio Testa M.D. (neurosurgeon, Ospedale Bellaria, Bologna, Italy) to organise a scientific meeting at their estate in Provence. The Fondation promotes invitational meetings concerning interdisciplinary topics. After consultation with Marco Leonardi M.D. (neuroradiologist from Università di Milano, Milan, Italy) these two physicians decided to plan a meeting to discuss the treatment of sub-arachnoid haemorrhages (SAH) from intracranial aneurysms in the context of the availability of interventional neuroradiology as an alternative to micro-surgical approach. The final decision was to hold a European meeting with the support of David Wiebers M.D., neurologist, and the International Study of Unruptured Intracranial Aneurysms (ISUIA) from the Mayo Clinic in Rochester, Minnesota.

Invitations were sent to a number of specialists, each one responsible for Centres known for their interest in neurovascular problems, and their experience in interventional neuroradiology. Others were invited to help promote the most effective organisation of the new neuroradiological technique in their Centres. The following letter was mailed to the invited physicians:

Dear Friends,

Therapeutic neuroradiology for cerebral aneurysms has continued to develop. Statistics from single active Centres or individual specialists have now risen from tens to hundreds of cases in particularly active Centres, since the 1993 Venice meeting organised by one of us (M.L.). At present, many neuroradiologists areanxious to move on from diagnosis to treatment, but there are no proper training courses at any of these Centres. Interventional neuroradiologists are currently accepted and trained at these Centres along the lines of a Renaissance craftsman. The aspiring therapeutic neuroradiologist gains permission to spend some period of time (as yet unspecified in length) at the Centre of his choice. There, he will observe or take part in operations./em>

Regretfully, the teacher is often more inclined to talk about his own performances than to explain how they are actually carried out in practice. After a period of time which varies from a few days to a few months, the neuroradiologist returns to his own Centre and tries to put into practice what he has observed and learned. Plainly, the difference in training varies widely from one case to the next. It is high time to establish general criteria to select trainee candidates, draw up a teaching programme, fix minimum training targets, etc.

Faced with the advances in therapeutic neuroradiology, vascular neurosurgeons have reacted in one of three ways.

1) Outright refusal based on mistrust of the new technique, a mistrust justified, for example, by the successes some neurosurgeons have achieved in hundreds or thousands operated aneurysms.

2) In contrast, total acceptance of new methods based on the general assumption that this non-invasive technique will become the therapeutic strategy of the future. This is the attitude most commonly encountered in Centres where excellent results are achieved in other areas of neurosurgery, but vascular surgery is not a major specialty. For this reason, open neurosurgery for cerebral aneurysms has either ceased or is limited to cases which neurosurgeons do not deem suitable for embolisation or in which embolisation has failed.

3) Lastly, there is a group of neurosurgeons who deem the technique promising, do not refuse to adopt any such procedure at their own Centre and usually agree to (and find constructive) case-by-case discussion with interventional neuroradiologists. It is this attitude which best suits when a definition of respective spheres of action is to be outlined.
To make any discussion as constructive as possible, it is essential to start from principles based on common sense and consolidated results. Endovascular neurointervention can be justified in so far as it is a non-invasive technique. Indications for procedures which explicitly entail additional risks (especially in still inexperienced hands) must be discussed. Avoiding any forced decisions ensuing from the desire to establish set therapeutic choices, but trying to find the best solution for individual cases will prevent neuroradiologists and clinicians from failures. In addition, the outcome of therapeutic neuroradiology should be compared not with the natural history of aneurysms, but with surgical results and with high standard overall neurosurgical statistics. Interdisciplinary treatment protocols should be devised as soon as possible.
Some centres have long focussed on global management and overall results evaluation as the only correct approach to the problem, when dealing with SAH due to cerebral aneurysms. The days when some neurosurgeons claimed that treatment consisted in clipping the aneurysm neck, are long past. Yet this attitude has reappeared in the guise of those claiming that treatment simply consists in occluding the aneurysm by embolisation. Global SAH management requires a novel approach which avails itself of the contribution (and limitations) of the new interventional methods. In short, new neurosurgeons and interventional neuroradiologists must together devise new protocols for the global management of SAH from ruptured cerebral aneurysms.
The protocol must be based on results accumulated up to now starting from significant cohorts of patients treaded surgically or by embolisation and assessing results prospectively. The main criterion is to interact on an ongoing basis with well-known neurosurgery departments and Centres specialised in interventional neuroradiology. Some of these Centres periodically process data from treatment protocols adopted on a prospective basis. This allows an assessment of personal experiences (and results) taken from patients’ series matched for disease morphology, localisation, age, physical and mental condition, length of time between SAH and hospital admission, or absence of SAH (intact or grade O” aneurysms), etc. Comparison of the overall results of SAH management in uniform cohorts treated by microsurgical techniques or neuroradiological therapy should disclose some general therapeutic criteria. Alternatively, and more realistically, guidelines can be put forward for each Centre depending on the facilities available there.

In our view, a meeting between neurosurgeons, neuroradiologists and neurologists specialised in this field to discuss these issues and draw a report would have an important outcome.
The French Fondation des Teilles has many years’ experience in organising scientific meetings and international exchanges on interdisciplinary topics. In 1983 the Foundation was the venue for a week’s meeting organised by one of us (CT) to discuss vascular neurosurgery problems.
Our meeting is planned for June 1995. If you are interested in attending our meeting, a draft programme with dates and topics for discussion will be sent to you together with the list of participants for any suggestions and comments you may have.
The following invited specialists attended the meeting.

A. Andreoli, M.D., Neurosurgeon, Bologna (Italy)
B. Richling, M.D., Neurosurgeon, Wien (Austria)
J.-P. Castel, M.D., Neurosurgeon, Bordeaux (France)
P. Schmiedek, M.D., Neurosurgeon, Mannheim (Germany)
R. Illingworth, M.D., Neurosurgeon, London (England)
I. Szikora, M.D., Neuroradiologist, Budapest (Hungary)
P. Lasjaunias, Neuroradiologist, Paris (France)
C. Testa, Neurosurgeon, Bologna (Italy)
M. Leonardi, M.D., Neuroradiologist, Bologna (Italy)
C. Trevisan, M.D., Neuroradiologist, Milano (Italy)
A.J. Molyneux, M.D., Neuroradiologist, Oxford (England)
J. Vajda, M.D., Neurosurgeon, Budapest (Hungary)
J. Moret, M.D., Neuroradiologist, Paris (France)
R. Villani, M.D., Neurosurgeon, Milano (Italy)
L. Picard, M.D., Neuroradiologist, Nancy (France)
D. Wiebers, M.D., Neurologist, Rochester (U.S.A.)

The meeting was held at Les Treilles from June 7 to June 12, 1995. The first session was devoted to formulating an outline of the major areas of interest which were discussed at the meeting,

This outline forms the basis for the report which follows. (A more detailed summary is presently in press on Interventional Neuroradiology).

1. Natural History of Unruptured Intracranial Aneurysms (UIA)
2. Natural History of Subarechnoid Haemorrhage (SAH)
3. SAH as a Disease
4. Management Protocols and Neurosurgical vs. Interventional Results
5. Standard Data Collection and Results Evaluation
6. Long-Term NS and INR Efficacy
7. Education and Training for INR
8. Team Approach and Organisation
9. Future Progress

1 – Natural History of Unruptured Intracranial Aneurysms

David Wiebers – ISUIA progress and future directions

This presentation outlined the design and progress of the International Study of Unruptured Intracranial Aneurysms (ISUIA). The plan is to accrue 3,500 patients from 54 Centres, 24 in the USA, 7 in Canada, and 23 in Europe between 1991 and 1996. Two thousand will be prospective and 1,500 retrospective. The primary hypotheses are:

1) Among patients with unruptured intracranial aneurysms (UIAs) without a history of subarachnoid haemorrhage (SAH) there is a critical size above which there is a significant risk of aneurysm rupture, neurological morbidity and mortality;

2) Among patients with UIAs and a history of SAH from a different source, the risk of future rupture of UIA, disability and death is greater than patients without a history of SAH and varies directly with aneurysmal size;

3) The risk of death and disability from surgery to isolate UIAs from the intracranial circulation varies with the size of aneurysm, the location of the aneurysm, history of SAH from another cause, and confounding variables such as age and associated medical conditions.

The secondary hypotheses relate to numerous variables other than aneurysm size which may be independently associated with an increased risk of subsequent rupture of UIA, including age, sex, hypertension, number of aneurysms, number of aneurysmal lobes, location, symptoms other than rupture, family history, alcohol consumption, tobacco consumption, oral contraceptives use, use of stimulants, associated conditions such as autosomal dominant polycystic kidney disease, presence of an unruptured AVM, discrepancies in cross-sectional imaging versus arteriography sizes of aneurysms and the performance of carotid endarterectomy.

Patient recruitment is on schedule and indicates approximately 74% female, 55% operated aneurysms in prospective patients and less than 1% of patients under the age of 20. Current and former cigarette smokers comprise 70% of the retrospective patients and 80% of the prospective patients. Over half of the unruptured aneurysms included in the study are less than 10 mm in diameter. It is projected that recruitment will be completed by the end of 1995 and results presented at the end of 1996.

The second phase of ISUIA is the planning stage and will include a molecular genetic component. A randomised trial is envisioned for the future if the results of the ISUIA I indicate that it is appropriate and needed for the entire group or some subgroup of patients with unruptured intracranial aneurysms.

Discussion. It was suggested that further knowledge of molecular and genetic factors might lead to important advances in the understanding of the processes of aneurysm formation and rupture, and may also facilitate clinically useful screening tests.

David Wiebers : Natural History of Unruptured Intracranial Aneurysms

* The magnitude of the problem – It was reported that in the years 1979, 1984 and 1989, U.S. National Hospital Discharge Survey data indicated that an average of approximately 10,000 patients with unruptured aneurysms were admitted in the hospital each year compared to 20,000 patients yearly with subarachnoid haemorrhage.

The frequency of unruptured aneurysms in autopsy studies has ranged from 0.2 to 9.9% with a mean of approximately 5% suggesting that about 13 million people in the United States have or will develop intracranial aneurysms. The magnitude of the problem of unruptured intracranial aneurysms is increasing because the population is aging and because of the wider availability of high resolution imaging studies that can detect unruptured aneurysms fortuitously. Available data suggest that aneurysmal size is the most significant single variable determining rupture for UIAs in patients with no history of SAH from different source. In these patients, aneurysms 10 mm or greater in diameter appear to be much more likely to rupture. When combinations of variables were assessed, the interaction term of aneurysm size times patient age was an even better predictor of future rupture. If age (in years) multiplied by size (maximum diameter in millimetres) exceeded 1,000 this indicated particularly high-risk. It was postulated that aneurysms develop over short periods of time, measured in hours, days or weeks, and then either rupture or stabilise. There appears to be a low risk of future growth or rupture if the initial stabilised size is less than 10 mm in diameter. The relationship between aneurysm size and future rupture is less clear for UIAs in patients with a history of prior rupture from a different aneurysm.

Discussion – Several other possible variables which could also influence aneurysmal rupture were explored, including the direct process of blood vessel wall repair (which could vary by site), aneurysmal wall thickness, presence of blood clot, multiple aneurysms and atheroma in the parent artery.

2 – Natural History of SAH

Robin Illingworth – The natural history of aneurysmal subarachnoid haemorrhage

To gain acceptance, any new treatment must be at least as effective as the methods it replaces, and confer some other identifiable benefit such as improved safety or ease of application. The standards and results which it must at least match, should be those of current clinical practice which are available for review. A review of selected papers published between 1967 and 1990 describing the natural history of the condition was presented. Pakarinen showed that 14% of patients died before admission to hospital and another 15% within the first 24 hours. Overall, 43 % died from the first haemorrhage and 67% within 6 months. In Locksley’s series of 830 patients with a single aneurysm admitted within 24 hours of haemorrhage, most deaths occurred within the first period of rupture. Thus in the first 2 days, 14% died, the same as within the next 5 days. This was the same percentage of survivors as died in the second week (15%), and the second month (16%). In contrast, only 0.8% of survivors died in the second 6 months. Overall, 62.7% died in the first year after SAH. Alvord analysed outcome in untreated patients in relation to grade on admission and time since haemorrhage. He concluded that these two factors alone allowed the outcome to be predicted with a high degree of accuracy. In his view no surgical series published up to that time (1977) obtained results significantly better than the natural history determined from non operated cases. Winn et al. following untreated patients from earlier series for a mean period of 10 years found an annual rebleeding rate of 3.5% with 67% mortality, the latter figure resembling that found by Pakarinen.

Throughout its evolution, the surgical management of Subarachnoid Haemorrhage has struggled to beat the natural history of this condition. The overall results suggest this has only been successful in some areas. One problem in evaluating the surgical results is that few series include patients who were not operated because of the deterioration before a planned procedure. This was addressed by the large multi-Centre observational timing at surgery study of Kassell et al. This study included 3,521 patients entered within 3 days after SAH, 83% of whom had surgery. All non operated cases were also included in the analysis. The surgical results were much better in patients who had a good clinical grade on admission, and in patients in all grades who were operated later. However, when patients who did not have surgery because of prior deterioration from all causes were included, the timing of surgery had relatively little impact on results. Only patients who had, or were planned to have, operation on days 7-10 did worse than those from other timings. This confirmed Testa (1985), who adopted from 1977 to 1982 a conservative approach waiting for delayed surgery (under optimal conditions up to 7 days after SAH). There was a 42% preoperative mortality for a consecutive patient series primarily due to rebleeding and vasospasm. In the study by Kassell, alert patients did better overall with early operation.

It was concluded that in any assessment of treatment results, crucial factors in outcome were the time of entry from ictus, the grade on entry, and the timing of treatment intervention. In all analyses the non operated patients must be included.

3 – Subarachnoid Haemorrhage as a Clinical Entity

Subarachnoid haemorrhage (SAH) from a ruptured aneurysm represents the beginning of what is often a severe, protracted and complex clinical course. When dealing with SAH from ruptured cerebral aneurysms, one must recognise that dipping or embolising is only pan of the long, painful story of SAH. All interventional neuroradiologist willing to perform endovascular procedures should know or learn the multiple and variously combined clinical aspects and course of the disease.

The Introduction was provided by Jean-Pierre Castel, with a summary of the neurosurgical literature. The review was intended to clarify the “state of the art” and this was done summarising surgical and overall management results to date. In the literature, there are indications of the acceptable rates of postoperative mortality and morbidity in ruptured and unruptured intracranial aneurysms treated by clipping. When unoperated patients were included in the overall results of surgical series (intention to treat), the mortality averaged around 29%. These figures could be greatly modified by referral patterns and, in particular, practices that were largely secondary or tertiary referrals rather than community based practice. There were multiple causes of deterioration. An analysis of over 7,000 cases from 9 large publications suggested an overall surgical mortality for all grades of 10-12% as against an overall management mortality of 28%.

Diagnosis and preoperative course (immediate diagnostic and therapeutic measures for patients, following initial grading).
The grading itself at admission may be difficult, for example, Hunt and Hess. Grade 4-5 patients, which are sometimes classified as such because of admission immediately after SAH or because of severe concomitant acute hydrocephalus. These patients may improve spontaneously over hours or minutes to when hydrocephalus is relieved. Thus, it was suggested that the grading be done later in cases not operated on an emergency basis. Moreover, such patients could be differentiated between those with massive bleeding and those with hydrocephalus.

Another difficulty with grading involves the incidental co-existence of significant risks factors, such as hypertension, cardiac and/or vascular disorders, old age, etc. These factors may lead to variable grading of patients with similar neurological condition.

There was a general discussion concerning the reliability of the commonly used grading-scales. It was concluded that, for admission grading, the Hunt & Hess scale is still preferred. However, every possible admission grading-scale is to be considered as approximate, due to high number of variations from a case to the next.

As to diagnostic procedures on admission and preparation to surgery, there is an obvious difference in planning between patients admitted in “good” (1-2) and “bad” grade (4-5). The same is true for patients admitted in “good” grade, but to be treated by early or delayed surgery. For “bad” grade patients, there is a great difference in planning between those to be treated in the ICU and those to be immediately submitted to emergency operations for life-threatening hematomas. Problems arise and immediate ongoing decisions are needed daily. This demands assiduous attention from neurosurgeons, neurologists and/or interventional-neuroradiologists responsible for therapy, supported by knowledge and concrete experience with proteiform aspects of SAH since the onset of bleeding. The combined efforts of neurosurgeons, neurologists and interventional-neuroradiologists was recommended.

As to angiography, conventional practice is that the study be performed on four vessels, with the support of cervical MR in cases with typical history of SAH but negative CT-scan and negative four-vessels angiography at admission. Many attending neurosurgeons after a negative angiogram, are prone to repeat it after some days, before considering a SAH sine materia. It was also questioned if, in case of typical peri-mesencephalic SAH, non-aneurysmal angiography was to be repeated. It was concluded that, if the first angiogram is of good quality, repetition in these cases is statistically more a risk than a diagnostic advantage.

The pathophysiology of vasospasm (VSP) was considered by Peter Schmiedek.
The participants agreed that, despite the research done, much remains unknown about the mechanism of VSP. There is agreement as to the importance of drugs such as Nymodipine. It was noted that Nymodipine did not influence angiographic VSP, but was effective in reducing ischaemic neurological deterioration from 32% to 22% if given orally, and from 32% to 14% if given intravenously. The current state of the Tyrilazad studies was presented. It may be effective in males at a dose of 6 mg, but a new study at higher dose is proceeding in females. It was also reported that the drug is licensed for use in very few countries. It was noted that in the collected literature, angiographic VSP was reported in 70% of persons with ruptured aneurysms (Adams, 1995) and yet delayed ischaemic neurological deterioration occurred in only 1/3 of these. Moreover, the importance of distinguishing non-haemorrhagic clinical deterioration from vasospasm demonstrated by cerebral angiography was stressed.

The frequency of pre-operative rebleeding was already reviewed in the section on natural history of SAH. In the context of aneurysmal subarachnoid haemorrhage, natural history studies show that the frequency of rebleeding is maximal in the first 14 days post-haemorrhage falling progressively to approximately 3% per annum in untreated patients at 6 months. Thus, if rebleed is going to occur with significant effect on outcomes, most will be seen in the first 14 days and du ring the first year after SAH.
Postoperative management – The discussion primarily concerned postoperative angiography. This is recommended as a standard procedure for endovascular cases immediately post procedure and at six months and one year, to confirm the stability of aneurysm occlusion. For micro-surgically treated aneurysms, angiography is recommended when there is uncertainty about complete neck occlusion and/or occlusion of parent vessels and perforating arteries, after the surgical procedure.

4 – Management Protocols and Neurosurgical vs. Interventional Results

Management protocols should take into account the risks associated with the natural history of aneurysmal SAH versus treatment risks in each identifiable patient groups. The necessity of balancing the treatment risk with the risk of re-rupture and vasospasm was emphasised. Treatment protocols were discussed to evaluate critically the results from treatment planning, particularly for patients admitted emergently, when decisions about early or delayed surgical/interventional neuroradiological treatment are most critical.

The series presented by Claudio Testa provides one example of progressive conceptual modification in terms of adopting an early or delayed surgery protocol. The results of aneurysmal SAH management accumulated by the Bologna group, with about 1,000 patients treated from 1977 to 1992, involved three prospectively defined protocols which identified an improvement in patients’ outcomes with each successive protocol. The Neurosurgical Unit in Bologna was presented as a “medium level” Centre, admitting about 2,000 patients per year and, of these, about 100 SAH. In 1977 they began with a rigid prospective protocol for delayed surgery. Now they follow a prospective “adaptable” protocol inclusive of early and delayed surgery as well as interventional neuroradiology. Their overall management results (73% good, with 23% overall mortality) are at present 26% better, in respect to the first protocol and series. This is due to successive realistic modifications of management every day and for every case, taking into account human and technical resources. Information from International Cooperative Studies on SAH is essential. This same information has, however, the unavoidable disadvantage of influencing mid-level units surgeons (i.e. around 90% of surgeons) with examples of excellent results from protocols suggested by excellent level units. Imitation of such protocols by mid-level units may be inappropriate. Results from excellent-level units must remain landmarks, delineating how far one can go with overall management when there is no fault with human or technical resources. They suggest that mid-level units can more easily attain acceptable or even remarkable results, by slowly administrating management protocols appropriate to the available human and technical resources.

Comparable results come from comparable series. Some attending neurosurgeons were asked to present data coming from “Best Possible Series” (BPS) involving patients in Gr. 1-2, bleeding from a single demonstrated aneurysm, less than 65 years of age and without relevant risk-factors. Comparison of overall and surgical management results is only possible for BPS admitted acutely after SAH and selected from admission. BPS selected just before surgery can be compared with respect to surgical results.

Accordingly, surgical results from a BPS 1984 1994, consisting of 140 patients Gr. 1-2 at surgery performed at the University Clinic of Milan, were reported by Roberto Villani. Ninety-two operated patients (66 %) came from a protocol for early surgery and forty-eight operated patients (34 %) from a protocol for delayed surgery. Distribution according to aneurysm location was the same as that of the overall population operated for a single aneurysm. Rebleeding while waiting for delayed surgery was 10 %. Outcome surgical results (see Tab. 1) were evaluated at discharge according to the GOS (Glasgow Outcome Scale) and follow-up according to the CESE (Clinical/Emotional/Social Evaluation). Surgical results were the same for patients assigned to protocols for early or delayed surgery. Roberto Villani said that the overall mortality rate observed in patients admitted in Gr. 1-2 is low. He suggested that the higher overall mortality rate observed in all-grade patients is mainly due to damages provoked by haemorrhage, deterioration from vasospasm, patients systemic and neurological conditions on admission, rather than to surgical treatment per se.

These surgical results are comparable (Table 1) to the BPS presented by Alvaro Andreoli and consisting of 148 patients in Gr. 1-2 at admission to Bellaria Hospital, Bologna, from 1984 to 1994, 0-3 days from SAH. This BPS was evaluated from admission to give overall management as well as surgical results. – As to interval SAH-admission, most patients were admitted very early after bleeding (66% in day 0). Advantages from early admission: starting appropriate medical treatment immediately and deciding ab initio in favour of early or delayed surgery protocols. Drawback from early admission: high risk of rebleeding, statistically maximal on the first day after SAH.

Timing of operation (i.e. early versus delayed surgery sub protocols) was tailored for every patient, early surgery being considered first choice, but this depending mainly on available assistance resources that same day. Patients enrolled in an early surgery protocol were operated as soon as possible and in any case within 72 hours from SAH. The delayed surgery protocol (surgery at least one week after SAH, Gr. 1-2, no vasospasm at angiography or TCD) was adopted for 1) admission close to 72 hours from SAH, 2) signs of incipient vasospasm (possible previous SAH), 3) vertebrobasilar or carotid “difficult” aneurysms, 4) angiography at admission not clearly demonstrative for an aneurysm, 5) neurosurgeon dedicated to aneurysm surgery not available in the acute phase. Within this “adaptable” protocol” (see also Testa, supra), 82 patients (55%) were submitted to early- and 66 patients (45%) to delayed surgery subprotocols. One hundred and forty of 148 patients (95% operative index) were operated on and this because 8 patients (12%) died while waiting for delayed surgery. Most patients submitted to early surgery were operated in day 0 (34%) and in day 1 (34%). Cerebral oedema was found in the majority of these cases and surgical manipulations on a swollen brain were difficult. Conclusions: the quality of overall results in “Good Risk” patients is mainly dependent on: 1) SAH/admission interval (in their series 66% admitted in the first 24 hours), 2) rebleeding before planned operations, mainly delayed (leading cause of bad results), 3) technically difficult aneurysms and/or atherosclerotic vessels. A comparison of results from early vs. delayed surgery protocols is impossible, when either sub-protocol is adopted depending on the above factors. Overall and surgical results are rather to be considered altogether and coming from the flexible attitude (Adaptable Protocol) they adopted prospectively. However, data coming from their Adaptable Protocol confirm that as to surgical outcomes delayed operations give somewhat better results, but early operations eliminate the heavy burden of deaths while waiting for surgery and, consequently, have a favourable impact on overall results.

Surgical (i.e. neurosurgical or interventional neuroradiological) results as well as overall results from consecutive all grade series discussed during the meeting are presented below.
Everyone made an effort to present data not per se, but with the primary intent to put together a basis for common neurosurgical/interventional discussion.
Neurosurgical series

Jean-Pierre Castel presented a case series from the Bordeaux group, delineating the results of convenient surgery for patients with ruptured A. Co.A. (Anterior Communicating Artery) and MCA (Middle Cerebral Artery) aneurysms, treated with a protocol for delayed surgery. He called attention to the potential for wide variation in operative morbidity and mortality rates depending upon the technical expertise of individual surgeons. He also presented information to suggest that the outcome may relate to aneurysmal location with higher operative morbidity and mortality rates associated with anterior communicating and vertebro-basilar circulation aneurysms. In A. Co.A. aneurysms, the preservation of the anterior communicating artery is strictly recommended to reduce the postoperative risk of confusion and memory problems. Some complex aneurysms need wide and clear surgical exposure to be safely obliterated. In most cases, delayed surgery is preferred for clinical and technical reasons. In MCA bifurcation aneurysm clipping, the use of temporary clips is safe and useful and recommended for large-neck aneurysms. Aneurysms situated at the first bifurcation branch are usually small but difficult to clip. For complex or large MCA aneurysms, delayed surgery is preferred. In other cases, timing of surgery depends on the clinical status of the patient.
Peter Schmiedek stated his “Personal experience with the last 100 SAH admitted in the neurosurgical clinic, University of Mannheim”, in the context of overall management and over a 2-year period. For these patients an attempt was made to offer optimal treatment of SAH. The majority were operated on early and only a minority underwent delayed surgery, e.g. those in poor neurogrades initially, those with additional risk factors or a few cases with vertebro-basilar artery aneurysms. Although the logistic and technical approach to these patients if fairly standardised from a neurosurgical point of view, minor changes were reported which seem to be useful additions. The use of titanium clips was found to be an advantage with regard to artifacts on postoperative imaging studies. The need for postoperative control angiography in all cases without exception was expressed. This is even more important in view of more recent interventional techniques for the elimination of aneurysms. The superiority of either technique depends on the rate of total and definite occlusion of the aneurysm. Finally, the ongoing dilemma with the treatment of vasospasm following subarachnoid haemorrhage was commented on. Although the use of calcium-antagonists has resulted in a better outcome, it does not seem to be the solution to the problem. Other therapeutic modalities, like the triple-H treatment, the use of rt-PA and of neuroprotective agents like Tyrilazad were discussed as well. This presentation made clear that aneurysmal SAH is a rather complex disease, with many unresolved problems.

Another large series of aneurysmal SAH was presented by Janos Vajda, who spoke about “predicting factors for surgical treatment of intracranial aneurysms, from Budapest aneurysm registry”.

The surgical results of a large cohort of patients from the Budapest Aneurysms Registry (2,500 with ruptured and unruptured aneurysms over 17 years) were presented, involving 11 surgeons with different level of experience. They see at present about 220 patients per year with haemorrhage. In 1993, there were 181 patients with aneurysmal SAH; 84 treated early, 91 delayed treatment. Of these, 27% cases rebled while waiting for surgery. Data analysis make it feasible to predict the outcome of any individual case or group. This has been also used for measuring efficacy of different treatment methods. The necessity of balancing the treatment risk with the concurrent risk of re-rupture and vasospasm was emphasised and for each identifiable patient group. Older, atherosclerotic females with larger recently ruptured aneurysms represent die group in which microsurgery should be avoided at all costs in favour of endovascular surgery. As to other predicting factors, the CT rating of the subarachnoid haemorrhage did not appear to predict future results of surgical treatment. It was suggested that the use of aneurysm registry data bank may help to compare microsurgical and endovascular procedures, they have only had GDC available for a short time and treated 21 patients. They would estimate that perhaps 35 patients per year with aneurysmal subarachnoid haemorrhage might be treated with GDC in Budapest.

Janos Vajda (“multiple intracranial aneurysms, a high risk condition”) raised also the problem of contemporary vs. two stages operations for multiple aneurysms. An agreement on the strategy and timing of treating multiple aneurysms could not be reached in the literature even in the era before endovascular surgery. To underline the importance of the topic the presentation then demonstrated the failures in the management of patients harbouring more than one cerebral aneurysm based on the data from the Budapest Aneurysm Registry (almost 3,000 operative cases). Selected cases demonstrated the difficulty in detecting all aneurysms. Earlier methods of cerebral angiography proved to be responsible for such diagnostic failures. Some aneurysms can hide on angiograms, especially behind a larger sac, they tend to be overlooked more easily in the case of an already revealed aneurysm or the ruptured one is misjudged as an incidental aneurysm and left for second stage surgery. The fatal rupture of a previously silent incidental aneurysm seems to be more frequent in patients who just underwent microsurgical repair for ruptured aneurysms. Bleeding from an asymptomatic sac probably increases at the haemodynamic tides of the peri-operative period. This negative experience led to the change of strategy and timing in the management of multiple aneurysms in Budapest. All surgeons agree that aneurysms in the same hemisphere or lateral sacs combined with axial ones should be repaired during the same procedure. The presentation stressed that for the aneurysms featuring a higher risk of rupture, the single session repair of all lesions using either the option of bilateral pterional craniotomies or that of contra lateral approach should be advocated. The technical feasibilities of a contra lateral approach and clipping of certain aneurysms were demonstrated. Hazards and disadvantages of the more aggressive surgery proved to be less significant in Budapest in the recent years than what the natural history of multiple aneurysms represented. Finally, it was stated that the policy of an aggressive treatment for all intracranial aneurysms is much more acceptable today as endovascular and microsurgical techniques with their possible combinations are used in all major neurosurgical Centres.

The discussion which followed the presentation dealt with many controversial points. The participants agreed that catheterisation of major arteries is the only way a DSA should be carried out which minimises the detection errors, although according to the experiences of many, small aneurysms in the acute phase of their rupture could be more difficult to visualise. However, this does not reach significance in clinical practice. The participants with expertise in microsurgery did not find it necessary to extend the dissection of vessels and clipping an aneurysm on the contralateral side and although they accepted in theory the danger of rupture of an untouched previously unruptured sac, nobody could recall similar cases. This kind of statistic needs a scientific approach. The general view was expressed that endovascular surgery, combined with microsurgery or alone, can prevent the above mentioned management failures.

Jean-Pierre Castel also presented his personal experience with overall and surgical management in a series of 84 consecutive aneurysmal SAH in the elderly (over 70) admitted from 1980 to 1991, with a minimum 6 months’ follow-up. The incidence of ruptured and unruptured intracranial aneurysms increases almost linearly with age. The naturel history of SAH after 70 years age engenders a tremendous amount of mortality. For these reasons, the occurrence of aneurysmal SAH in elderly patients represents a real medical problem. The age limit for neurosurgical management of SAH is still debated. For many Authors, 65 years of age appeared until now to be the outside limit for surgical treatment of ruptured intracranial aneurysms, in spite of recent important advances in SAH management. In the elderly, the surgical treatment of an intracranial aneurysm is risky and is not always possible or indicated because of the patient’s clinical condition or technical problems. Furthermore, standards of management for aneurysmal SAH at this age have not been confirmed. The Bordeaux protocol called for medical therapy in all cases, surgical treatment of acute hydrocephalus when indicated, surgical treatment of ruptured aneurysms for patients in good clinical condition under the age of 75. Overall management outcome was checked against surgical outcome.

The day of SAH was considered as day 1. Clinical evaluation on admission, following the World Federation of Neurological Surgeons Scale (WFNSS). Quantification of the amount of subarachnoid blood on the CT-scan was done, according to Fisher’s scale. The outcome evaluation at one month and 6 months utilised the Glasgow outcome scale (GOS). Long-term follow-up consisted of a single item, dead or alive.

Conclusions: surgical treatment for ruptured intracranial aneurysm is still possible and relevant even after the age of 70 to protect the patient from rebleeding, but this applies only to a small group of selected patients. After SAH in the elderly, acute hydrocephalus is frequent; the indication for surgical CSF shunting is not dependent on age. Late rebleeding (after 6 months) was not observed. As an alternative to the risky surgical treatment, a less aggressive therapy like an endovascular procedure would be preferable to protect elderly patients as soon as possible from fatal rebleeding.

Interventional neuroradiological series

Current results from interventional neuroradiology were presented as treatment results, comparable to surgical results from neurosurgical series. Two papers from Andrew Molyneux, are summarised.

1) Endovascular treatment with GDC coils of acutely ruptured intracranial aneurysms

Presentation and results (comparable with surgical results from neurosurgical series) are summarised in Tab. 4. – Causes of death: 1 Rupture of incidental MCA awaiting clipping 1-month post Rx; 1 Generalised Ischaemia 7-days post exploration of basilar tip aneurysm treated with GDC 24-hours post-surgery; 1 Intraprocedural rupture of adjacent aneurysm; 1 Delayed Ischaemia-parent vessel occlusion; 1 Grade 5: age 67 post second bleed.

2) Posterior circulation treatment results 1992-1995: 85 patients with posterior circulation aneurysms – from a consecutive series of 190 patients treated with GDC

Location, presentation, size and outcome: see Table 5.
– Causes of deaths at 2 months: 1 patient bled awaiting clipping of incidental MCA (1 month); 1 patient treated Day-1 after failed surgery, generalised; Ischaemia on Day 7.
Later deaths: 1 at 6 months continuing brain stem compression (giant Mid-Basilar with thrombus); 1 72 years old at 10 months sub totally treated giant aneurysm bled for first time.

Another large series of aneurysms treated by interventional neuroradiology comes from Luc Picard (Hôpital Saint Julien, Nancy): Endovascular treatment of intracranial aneurysms with Guglielmi detachable coils.

One hundred forty-five aneurysms were treated in 135 patients by endovascular technique. 42 (31%) out of 135 patients had multiple aneurysms). – 77% SAH, 23% incidental. – 26% less than 4 mm, 47% 4-10 mm, 15% 10-20 mm, 12% greater than 20 mm. High percentage of poor grade patients (48% H.H. Gr. 3-4 or 5). Seventy-one percent patients admitted after SAH resulted Fischer grade 3 or 4 on CT scan. – 1/3 patients required CSF shunting before or after treatment.

Technical complications: A) Peri operative rupture of the aneurysmal sac occurred in 3%. Favourable outcome. No permanent deficit at follow up; B) Erratic migration of coils was observed in 4% cases; of these, only one patient experienced a thromboembolic complication; C) Most complications resulted from thrombo-embolia (5%); of these, 3 resulted in cerebral infarction; 5 patients recovered completely. – Mortality: all deaths (10%) were related to spontaneous evolution of intracranial haemorrhage. A) Rebleeding from 2nd aneurysm: 2 patients; B) Diffuse Vasospasm: 3 patients; C) Cardiac respiratory failure: 5 patients; D) Continued coma: 2 patients; E) Intracranial hypertension + edema: 1 patient. One patient, treated for a ruptured right aneurysm, died because of a successive
huge intracerebral hematoma from a contra lateral AVM, not treated in the same session.
Factors influencing aneurysm neck re-canalisation: these are incomplete obliteration, large size of neck and flow dynamics. Concerning anti-coagulation: all procedures are realised under systemic heparinisation. At the end of the procedure, there is no neutralisation by protamin sulfate. The patient is immediately treated by low molecular heparin (Fraxiparine) to obtain an efficient anti-coagulation. Owing to this new procedure, the rate of thrombo-embolic complications resulted lower than 2% for the last 50 patients. This anti-coagulation covers a period of 3 days systematically and one week in the case of bulging of the coils inside the parent artery.

– Angioplasty for the treatment of vasospasm. Used only for patients already harbouring some clinical deficit and this only 3-4 times per year, considering the risk of arterial rupture.

– Hospital costs for GDC treatment, in comparison with neurosurgical treatment in Nancy: Endovascular total length of stay: 10.2 days F. frs 63,000 ($ 12,608). The mean cost of the endovascular procedure is F. frs 25,000. During last months, the mean hospital stay is less than 7 days for 71 % of patients treated with GDC. Mean neurosurgical length of stay: 14.8 days (4 days in ICU), F. frs 98,000 ($ 19,600). The mean cost of surgical procedure is F. frs 8,475 ($ 1695).

Discussion on occlusion of carotid siphon by balloon for treating some giant or intracavernous aneurysms. Luc Picard suggested the use of EEG or TCD during test occlusion. The same test occlusion is realised under accurate clinical and angiographical checking. One of the most important points is to perform the occlusion test with low arterial blood pressure. Some of the participants deem EEG or TCD unnecessary, maintaining that clinical and angiographical checking are sufficient for safe occlusion. However, Luc Picard thinks EEG or TCD is mandatory for high-risk patients, such as elderly. David Wiebers said that he is unaware of data concerning the effective value of EEG recording during interventional endovascular procedures.

Pierre Lasjaunias points to the value of phlebography and asked the audience if cases have been seen of water-shed infarction occurring after and notwithstanding previous normal phlebography. Jacques Moret affirms that such cases are worth collecting.

5 – Standard Data Collection and Results Evaluation

Comparison of results coming from anecdotal series is often difficult due to variable criteria adopted for presentation. This is particularly true when interventional/neuroradiological results are compared with surgical results from neurosurgical series. A uniform outline as to how personal results are to be reported is greatly needed. During discussion, a few but possibly sufficient general criteria to facilitate comparison over focal points were proposed by Claudio Testa. The following data should be collected for every SAH series to be discussed. A) Number of patients and % admission 0-3 days from SAH. Comment: it should be stressed that only with patients admitted 0-3 days one is confronted with the decision, to be taken at admission, to treat a patient following protocols for early or delayed surgery. Consequently, comparable overall management results from both protocols, in the same or for different patient series, can be extracted only from 0-3 days admissions. B) Mean Age – Grading at admission: Good Grade, % H & H 1-2-3: Bad Grade % H & H 4 (H&H5). Comment: interventional/surgical results on unruptured aneurysms should be presented separately, for evident differences in management and percentage of expected successful performances. It should be decided if Gr. 5 (i.e. moribund patients) are to be included or separately presented, when results are discussed coming from overall management for all grades series. Bernd Richling introduced the concept ’of a “good group” and a “bad group” within grade 4/5 at admission. Alvaro Andreoli stressed the well-known scenario of some patients admitted to emergency and immediately after SAH in Gr. 4-5, but this being only the immediate reaction to the bleed. The same patients result in Gr. 1-2 a few hours later if not immediately submitted to angiography and emergency operation. These seemingly, but not true Gr. 4-5 are to be kept in mind when evaluating surgical results from emergency operations on “bad grade” patients. C) Surgical results and overall management results should be separately presented for Early Surgery Protocol (treated < 72 h, from SAH) and respectively for Delayed Surgical Protocol (treated > 72 h. from SAH). Comment: in Early Surgery Protocol, surgical and overall management results are generally coincident, all patients being candidates to be operated as early as possible. However, rebleeding (maximal risk in the first 24 hours) in patients admitted on day 0 can make surgical and overall results from Early Surgery Protocol non coincident. D) Results should be expressed after a minimum follow-up of 6 months (to be specified) and using a simple outcome scale thus minimising the possibility of misunderstanding: % Good: % Poor; % Death.

Comment: if the goal in overall management of SAH is to return to the family and to society an active member, then the mention “Good” means the favourable issue from SAH and includes all patients (possibly with some minor disability) finally resulting fully independent. Comments such as “reassuming his previous life” are equivocal, too many factors are involved, e.g., re-turning to previous work. Consequently, the mention “Excellent” should be abolished. On the other side, the mention “Poor” should include all significant disability making an operated patient not fully independent.

As to long-term evaluation for surgical results, suggestions came from a presentation by Roberto Villani, “effective social reintegration for patients operated for ruptured cerebral aneurysms”. This was an historical comparison study focusing on the results of late surgery performed largely in the time period of 1974-1984 versus early surgery performed largely in the time period 1988-1994. A plea was made for more accurate and detailed clinical and neuropsychological means of assessing patients. Data were presented suggesting that as to clinical evaluation, CESE (Clinical/Emotional/Social Evaluation) may be preferable to the GOS (Glasgow Outcome Scale) in evaluating patients at one year postoperatively. From a neurological point of view, he indicated that results seemed better with late surgery than with early surgery, but the difference was not so apparent for the MCA aneurysms. From a neuropsychological point of view there was no difference in long-term outcome between early vs. late surgery. Only for ACA aneurysms results were different and this in favour of early surgery.

6 – Long term NS & INR Efficacy

This was one of the most discussed topics in this meeting. As to interventional treatment, a Cooperative Study was proposed by Andrew Molyneux, presenting an International Subarachnoid Aneurysm Trial: ISAT trial and a rationale for performing a randomised trial to test the safety and efficacy of endovascular treatment of ruptured intracranial aneurysms compared to conventional neurosurgical treatments. The study will assess overall morbidity and mortality as well as rebleeding rates associated with both procedures. A further component in selected Centres will involve an assessment of neuropsychological and psychosocial problems as well as a cost analysis related to both types of procedures.

Randomisation will be based upon the uncertainty principle and follow-up will be conducted primarily by patient questionnaire. The planned sample size is 1,232 patients over approximately 4 years. A pilot trial is currently underway at Oxford and the full study is pending funding by the UK Medical Research Council.

There was spirited discussion and divergence of opinion starting with the necessity and impact of such a trial at this time. There was a wide ranging discussion regarding several aspects of a study, including whether or not the trial was indicated at this point and time, the philosophical basis for such a trial, the applicability of the results to the broader group of subarachnoid haemorrhage patients, whether or not broad numbers of patients can be randomised from individual Centres, the validity of the uncertainty principle in randomisation schemes, and logistical and ethical considerations regarding randomising individual patients.

7 – Education & Training for Interventional Neuroradiologists

Marco Leonardi pointed out that in Italy and elsewhere, there are no formal training programs and training is difficult, particularly for senior neuroradiologists. The interventional neuroradiologist has to be trained in well recognised Centres, through a progressive program which starts with the use of micro-catheters for low risk vascular territory lesions, continues with attempts to position the catheters within the aneurysm and ends with the embolisation of those aneurysms particularly difficult to reach. The interventional neuroradiologist should be aware of the problems concerning patient monitoring during and after the procedure and should interact with the anaesthesiologist.

Claudio Trevisan is a representative of those responsible for neuroradiological units who recently decided to add interventional neuroradiology to already available techniques. He is chairman of a large neuroradiological unit in a Neurological Department, where two divisions of neurosurgery and one of neurology coexist. Neuroradiological techniques and performances arc strongly diversified in relation to numerous and often contrasting interests emerging from groups of neurosurgeons, neurologists, and neuroradiologists. Neuroradiologists were over the years quite indifferent to the evolution of neurosurgical treatment for SAH. Years ago, neurosurgeons working in their Centre ceased considering patients as carriers of aneurysms to be clipped and pointed instead to overall treatment of SAH through reasoned protocols.

Progressive modifications, lead to a significant improvement in outcomes. Neuroradiologists supported the surgeons’ work, without actively taking part. At present, the introduction of interventional endovascular procedures has altered the relationship between neurosurgeons and neuroradiologists, raising a series of problems of no simple solution. Two of these problems are particularly pressing a) preparation and training for interventional neuroradiologists and b) the definition of a protocols establishing which patients should be treated by microsurgery and which by endovascular procedures. The preparation and training of the neuroradiologist is a problem of scientific societies. These have to evaluate where candidates should be sent to learn, how long they should stay or, more important, how many interventions they have to attend at directly participate in, before being authorised to operate independently. He does believe that an expert angiographer, already possessing the skills for other interventional procedures, needs only a short apprenticeship. However, candidates should be in the end capable of dealing with cerebral aneurysms, not only from the perspective of manipulating technical instruments, but also from the perspective of discriminating operative indications as well as procedures allowing apparently easy solutions, but prone to display a relatively high number of unpredicted failures and serious complications. Secondly, through the delicate transition phase in which the effectiveness of new procedures is not completely certain, the proposal and adoption of protocols which identify those cases to be treated surgically and those to be treated endovascularly would be auspicious.

After these introductory remarks, Pierre Lasjaunias, Chairman of the session, gave the lecture here summarised “The philosophy of education”- Duties of teaching: Philosophy. A technique is of no value if it is not mastered and a technique must be integrated in a full course of training and as part of a process. It cannot be a “transplant”. The speed of the apprentice will grow with practice and will vary but there must be time for maturity. Maturity gives reproducibility. Mastership is the quality of decision making and is the final goal. – Decision and Execution. Mean knowledge is “consensus”. Synthesis of knowledge is integration. The future of the technique will disappear but the future of the concept will not. The history of education up to the 18th century is heritage and tradition. After the 18th century, education was to transmit knowledge for the student to surpass the teacher and go beyond. The teacher must accept responsibility for the knowledge (sources of knowledge, reference research editorials). There is an English monopoly on information (international censorship). This suppresses non comprehensive language and if you do not comply with the rules you cannot pass the bar. The medium establishes the rule of the message. A message in poor English is often interpreted as a poor message and silence is regarded as an absence of opinion. Teaching is the expression of the knowledge and understanding. “It is not enough to Write but the writing must be read”.

Goal of Competence. Accuracy of preoperative decision making cannot be trained in a few months. Basic ethics, technical aspects. Algorithm 3 steps: theoretical, maturity, mastery. The role of the tutor is to spread knowledge for critical analysis in decision making, and to teach doubts, and how to work and grow with them. Worldwide challenge is of education practice and teaching but are the techniques affordable by the rest of the world? This was followed by a lively discussion.

8 – Team Approach: Organization and Results

The necessity to work in team, neurosurgeons and interventional neuroradiologists as well as neuroanaesthesists, was shared by all participants. Some Centres have already acquired enough experience with team approach to SAU. Some other Centres are just starting this new way of working.

The problem was introduced by Claudio Trevisan. The experience of his group is presently in the initial phase. With a few exceptions, it was only with elderly patients and generally in poor conditions that surgeons in Bologna were in doubt about operating. These are the patients they selected to put interventional neuroradiology to the test. He finds it necessary to establish for the future which aneurysms are to be treated surgically, and which must be left to neuroradiologists. This by no means is intended to withdraw the activity from neurosurgical practice. He is rather thinking of material and moral sufferings coming from neurosurgical operations. Not to mention the economical aspect. The adoption of a protocol should aim to make this activity free from paternalistic attitudes or, conversely, should help to avoid the albeit rare submissive attitude of some neurosurgeons.

Marco Leonardi gave some more details, as to correct planning of team organisation. Neuroradiological endovascular treatment of intracranial aneurysms should be performed when it appears to be safer, less expensive and less invasive than surgery. Patients must be selected, after a careful evaluation of both surgical and neurointerventional feasibility, in agreement with neurosurgeons. Even when surgery is clearly feasible, the endovascular treatment can be the first choice immediately after the diagnostic angiography session and, in case of failure, surgery can be performed later. Interventional neuroradiologists cannot substitute for neurosurgeons, but rather should work with neurosurgeons to get the best results in a complementary organisation. A team approach is necessary for endovascular work. Whoever tries to work independently, just because the neurointerventional materials are today easily available, will be greatly disappointed. As to capabilities, he recommends at least two interventional neuroradiologists in a team.

In Budapest interventional neuroradiological activity on cerebral aneurysm is just starting. Their criteria as to team-work were illustrated by Istvan Szikora who spoke about “patient selection for endovascular and microsurgical treatment of intracranial aneurysms: a team approach”. Proper patient selection requires a team effort with neurosurgeons, interventional neuroradiologists and neuroanaesthesists equally involved. While microsurgery remains the gold standard for treatment of intracranial aneurysms, an increasing number of such lesions are treated in Budapest by endovascular technique, using the GDC System. As the ultimate goal of treatment is to prevent a particularly high incidence of re-rupture in the acute phase following SAU, early patient selection criteria for interventional neuroradiology were based on contraindication for surgery. According to their strategy, patients with medical condition predicting high surgical morbidity or mortality are to be treated with GDC in the acute phase, independent from aneurysm morphology. These criteria did not consider the inherent advantages and limitations of the technique. On the other side, elective treatment with GDC is offered to patients harbouring aneurysms with optimal morphology: GDC treatment should be considered as an option for large and giant aneurysms that carry high technical risk associated with surgery. The effectiveness of coil treatment in such cases remains to be further evaluated. – Angiographic follow-up is necessary to prove the long term results. Incompletely occluded aneurysms should be either retreated or operated on at a later time.

An example of large experience with a team-approach (neurosurgical and interventional neuroradiological) was offered by two presentations from Jacques Moret concerning treatment for intracranial saccular aneurysms (1).

1) Endovascular treatment of non-surgical aneurysms

2) Endovascular treatment of surgical aneurysms

This was a review of 352 patients where coil treatment was attempted. The practice in their Institution is to attempt coil treatment first, followed by surgery if this fails. 44 patients were not treated by coils (12.5%) and these patients were prepared for surgery. 18 had atherosclerosis preventing access to the aneurysm. In 28 patients, a decision was made not to embolise and they went to surgery. 284 patients were treated endovascularly. 23 patients had 2 aneurysms, 2 patients had 3 aneurysms. Most patients were treated with GDC (191), 81 with MDS, 12 with both. Aneurysms less than 5 mm are always treated with GDC. – All complications were reported on what is described as a binary scale and procedure related complications only were reported. 127 acute aneurysms (treated within 3 days) with 10 neuro complications and 3 deaths. 88 non-acute aneurysms, 2 neuro complications, 1 death. Grade 0 patients: 109 patients, 7 neuro complications, 0 death. Analysis/decision not to embolise: 12/28 were MCA most complicated to treat because of difficult anatomy, 2 rebleeds in the series after partial packing. This was early in the experience and this is no longer done. 48% of complications related to MCA aneurysms. Long term follow-up: 284 treated, 252 cured angiographically long term, 207 in one session, 25% in multiple treatments, 74 partially treated greater than 90%, 41 retreated to cure. There were 7 recurrences but true aneurysm enlargement is very rare.

Prospective study of 50 patients treated acutely after SAH with one-year neurological follow-up. GOS 1/2, 87%, GOS 3/4, 6.5%, and death 6.5%.

Another Centre experienced with team approach to SAH from ruptured cerebral aneurysms is Vienna. This was demonstrated in two presentations by Bernd Richling.

1) GDC-treatment or surgery: indication criteria for a non preselected aneurysm population

2) The Vienna GDC experience. Follow-up and late results

What is an operable aneurysm? Deciding if an aneurysm is difficult to operate depends on the surgeon’s personal experience and skill. Microsurgery. Drawbacks of surgery: craniotomy (post-operative haemorrhage, infection), brain and vessel manipulation, danger of peri operative aneurysm rupture. Advantages of surgery: clearing of CSF spaces, good 3 dimensional knowledge of the aneurysm, variety of clips according to anatomical situation, high stability clip-. Endovascular treatment. Drawbacks: poor 3 dimensional knowledge, sometimes complete neck occlusion difficult, stability of results questionable. As a matter of facts, the 3-dimensional geometry of the aneurysm neck influences coil stability. The stability of the angiography results may be unreliable in patients with less than 90% occlusion. Aneurysms with wide neck are a poor indication for endovascular treatment. Advantages: vasospasm less of a problem, minimal manipulation of vessels, no need of difficult surgical approaches. Results. These were expressed by the Hunt and Hess grading scale at time of treatment, against the Glasgow Outcome Scale at 6 weeks follow up. Grade O (20): all had good outcome. Grade 1/2 (105): clinical outcome is equal for surgical and endovascular treatments. A GOS 1-2 could be achieved for 93% (OP) and, respectively, 95% (EMB) patients. Grade 3 patients (53): 70% GOS 1-2 for surgically treated patients; 87% GOS 1-2 for patients treated by embolisation.

Grade 4/5: GOS 1-2 was 42% for surgically treated patients; GOS 1-2 38% for patients treated by embolisation. It was in many cases difficult to assess grade 5 patients, because of intensive care applied by emergency teams (patients ventilated and paralysed and not assessable). Technical complications from 118 embolisations were 3 perforations (1 death), 4 thromboembolic complications (1 death). 6 patients underwent surgery after coiling. It was quite easy to operate the coiled aneurysms and the operative findings showed “the coiled part of the aneurysm being dead”. Conclusion on SAH aneurysms: results from surgery and, respectively, endovascular procedures were equal for Grades 1-2. Endovascular better for Grade 3. No difference in results for Grades 4-5. No rebleeding was observed in coil treated patients. – The decision criteria as to aneurysms suitable for surgery were as follows: no neck (ratio sack/neck > 1), no SAH (surgical dissection easier), Fisher grade 3 or less, anterior circulation, hematoma requiring evacuation. Criteria where embolisation is more appropriate: evident aneurysm neck, vasospasm, multiple SAH (scares making dissection difficult to be expected), giant aneurysms (difficult to embolise but even more difficult to operate, in case balloon occlusion of the parent vessel!), posterior circulation, poor general medical and biological condition.

9 – Future Progress

An effort was made by attending neurosurgeons and neuroradiologists, to foresee possible future technical or conceptual ameliorations.

Preventing loop escape – One of well-known complications of aneurysms embolisation is the escape of GDC-loops from the sac into the lumen of the feeding vessel. This is particularly frequent in cases of large-neck or giant aneurysms. It was suggested that a possible solution could be a coil modification apt to fix different loops contact points, thus preventing the escape during or at the end of the procedure.

Preventing compression – This is another known complication in interventional neuroradiology, particularly when dealing with giant aneurysms and in the first phase of thrombotic process. An amelioration of this drawback may demand coils material modifications.

Direct Visual endovascular inspection – The possibility of having direct endovascular visual access to aneurysmal sac and neck should be a great and self-evident advantage for interventional neuroradiological procedures.

Genetic and molecular factors – An understanding of the molecular pathogenesis of the formation growth and rupture of intracranial aneurysms may lead to the development of DNA screening tests to identify individuals at high risk for the trait and to formulate therapeutic intervention to halt or reverse the process.

Neuroradiological diagnostic technique – Evolving neuroradiological diagnostic techniques may provide significant advances in the management of intracranial aneurysms. One such technique is cinephase contrast MR angiography which can define pulsatile increases in aneurysm size during different phases of the cardiac cycle. Such size changes could for instance help define which unruptured intracranial aneurysms would be more or less likely to subsequently rupture and could ultimately help guide management decisions.

Neurologic intensive care – Overall management of SAH from ruptured cerebral aneurysms has been, up to now, mainly dependent on neurosurgical competence. Patients are commonly treated in I.C.U. and under neurosurgical supervision when required by serious medical conditions. The role of I.C.U. specialists, with their competence in the treatment of cerebral coma and correlated complications, has been undoubtedly underestimated in the past and currently under-utilised. A direct involvement of these colleagues in SAH management from admission to outcome, could be one of the most profitable initiatives for the next future.

(1) This summary, recorded during the meeting, shows some evident miscalculations, that Dr. Motet was successively asked to amend. Unfortunately, we had no answer up to now.

Contributions

• Alvaro Andreoli – Early and delayed surgery for intracranial aneurysms: evaluation of a prospective adaptable protocol over a best possible patient series
• Jean Pierre Castel – a) Personal experience with A. Co. A. and M.C.A. bifurcation ruptured aneurysms, treated with a protocol aiming to delayed surgery – b) Recent data on overall and surgical treatment for selected series of intracranial aneurysms
• Robin lllingworth – The naturel history of aneurysmal subarachnoid haemorrhage: a killer disease
• Pierre Lasjaunias – Education of neuroradiologists
• Marco Leonardi – The endovascular treatment of brain aneurysms. Starting a new therapeutical approach
• Andrew Molyneux – a) Endovascular treatment with GDC coils of acutely ruptured intracranial aneurysms – b) Endovascular treatment with GDC coils of posterior circulation aneurysms: consecutive series of eighty-five patients – c) International subarachnoid aneurysm trial: the rationale for a randomised trial
• Jacques Moret – a) Endovascular treatment of nonsurgical aneurysms – b) Endovascular treatment of surgical aneurysms
• Luc Picard – a) Endovascular treatment of intracranial aneurysm by GDC – b) Endovascular treatment of carotid siphon aneurysm
• Bernd Richling – a) The Vienna GDC experience, follow-up and late results – b) GDC treatment or surgery: indication criteria for a non preselected aneurysm population
• Peter Schmiedek – a) Lessons learned from the last 100 patients with SAH – b) Reflections on some unresolved pathophysiological issues of SAH
• Istvan Szikora – Patient selection for endovascular and microsurgical treatment of intracranial aneurysms; the team approach
• Claudio Testa – Adaptable protocols for SAH from ruptured cerebral aneurysms
• Claudio Trevisan – Organizing aneurysms endovascular treatment in a large neuroradiological unit
• Janos Vajda – Multiple intracranial aneurysms, a high risk condition? Who has the highest risk when treated microsurgically for intracranial aneurysms based on Budapest aneurysm registry?
• Roberto Villani – Early and delayed surgery for intracranial aneurysms: over a best possible patient series
• David Wiebers – a) Natural history of unruptured intracranial aneurysms – b) ISUIA results and future direction

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