Ruptured cerebral aneurysms: early and late prognosis with surgical treatment

Transcription

1 J Neurosurg 59:6-15, 1983 Ruptured cerebral aneurysms: early and late prognosis with surgical treatment A personal series, REGINALD H. SHEr HARD, M.D., F.R.C.S. Trent Regional Department of Neurosurgery, Derbyshire Royal Infirmary, Derby, England ~" An account is given of a personal prospective series of 815 patients with the syndrome of spontaneous subarachnoid hemorrhage (SAH) due to ruptured cerebral aneurysm. It concerns all aneurysm patients at risk, both surgical and nonsurgical cases, referred to the author during two main periods: 606 patients were treated during the earlier period of 15 years, and 209 in the subsequent 7 years. The early mortality rate was determined at 3 months, and all survivors in the first period were followed for a mean of 9 years. Only operation survivors were observed during the second period, for 3 years on average. Patients alive at 3 months were studied in detail with respect to disabilities, work capacity, and later mortality. Of the 815 patients, 613, or 75 %, were operated on. Comment is made on the influence of certain factors on early mortality. These include age, hypertension, condition of the patient at admission, and number of hemorrhages. From the results of this series, it is suggested that the preferable time to operate is between the 2nd and the 4th day after a single SAH. In this period, the early mortality rate is in the order of 10%. In this subgroup, a high proportion of the patients were in Botterell Grades 1 and 2, with only a few being in Grade 3. Also evident from the results was the protective value of operation against further aneurysm rupture in the 501 patients surviving at 3 months. However, the propensity of a second aneurysm to rupture in patients with multiple aneurysms has resulted recently in a change of operation policy. The early mortality in the whole series and later mortality in patients surviving 3 months is shown in tabular and histogram form. From these, it is clear the majority of later deaths are from causes unrelated to aneurysm rupture. KEY WORDS 9 aneurysm rupture 9 prognosis 9 follow-up study 9 subarachnoid hemorrhage 9 arteriovenous malformation 9 aneurysm surgery W vhile the literature on cerebral aneurysms is profuse, contributions on the long-term results are few. This is due in most series to incomplete long-term observations on survivors. There have been relatively few studies of the total initial aneurysm population at risk, and examination by one surgeon of the whole spectrum of spontaneous subarachnoid hemorrhage (SAH) and its principal causes is unusual. The present communication on ruptured aneurysms derives from a prospective personal study of patients with spontaneous or nontraumatic SAH. It concerns early and later mortality and follow-up observations, including disabilities and work capacity. The policy was to accept patients with the syndrome of spontaneous SAH as soon as they were fit to travel. They came from a large part of the East Midlands of England (33% from the hospitals in Derby), where the population is relatively stable. This has permitted longterm follow-up of the great majority of survivors, mainly at out-patient clinics and in some by annual letter. Although some patients have moved out of the area or emigrated, correspondence has been maintained. In all patients who underwent craniotomy, the aneurysm surgery was carried out by the author, as were a large proportion of the follow-up interviews. This is not a series in which surgical treatment is compared with nonsurgical management; patients not having operation were considered unfit for it on the basis of their neurological status, severe concomitant disease, or advanced age. Very few patients refused operation. 6 J. Neurosurg. / Volume 59 ~July, 1983

2 Prognosis of surgically treated aneurysms Patient Population Clinical Material and Methods During the 22-year period, 1180 patients were referred to me with spontaneous SAH. Only patients submitted to angiography or operation, or in whom diagnosis was confirmed by autopsy, have been included in this series. Specifically excluded were those with primary cerebral hemorrhage or with other causes of SAH, such as brain tumor or blood dyscrasia. Thus, the series comprised patients with ruptured cerebral aneurysms, those with hemorrhage from an arteriovenous malformation (AVM), and those with SAH and normal cerebral angiograms (Table 1). This study involves the 815 patients with ruptured aneurysms. Of these, 719 had single lesions, and 86 (11%) had one or more unruptured aneurysms in addition to the lesion responsible for the hemorrhage. A total of 613 were operated on, for an operability rate of 75%. Most of these were submitted to craniotomy for direct intervention on the aneurysm. Of 222 patients undergoing surgery for internal carotid artery (ICA) aneurysms, only 34 (15%) were treated by cervical carotid artery ligation; the mortality and morbidity rates differed little from those associated with direct procedures. The aneurysm arose from the anterior communicating artery (ACoA) in 256 patients, 190 of whom had surgery; the ICA in 288,222 of whom had surgery; the middle cerebral artery (MCA) in 202, 161 of whom had surgery; the proximal anterior cerebral and pericallosal arteries in 33, 28 of whom had surgery; and other arteries in 36, 14 of whom had surgery. Patients were studied in two main periods; the first period of 15 years ranged from April 1, 1958, to March 31, 1973, and the second of period of 7 years from April 1, 1973, to March 31, Patients in the first period comprise the early series. Treatment Modalities Craniotomy: Direct Intervention. Wherever possible, direct attack on the aneurysm has been the procedure of choice, but occasionally indirect intervention has been dictated by the circumstances of the operation (see below). The procedures employed for direct intervention included: 1) clipping; 2) ligation; 3) clipping and ligation; 4) clipping and wrapping; and 5) wrapping. A clipping procedure was used in the majority of patients. Until 1965, the clips were made from tantalum sheet fashioned to suit the particular aneurysm. These were sometimes difficult to apply accurately and, not being spring-loaded, were more likely to slip, especially in hypertensive patients. During the next decade, Scoville clips were used almost exclusively; in recent years, Heifetz clips have also been employed. Ligation of the aneurysm was the sole procedure in only a few of the early cases; clipping was combined with ligation in a few cases. Wrapping of the aneurysm was carried out with muscle or gauze. This has been TABLE 1 Summary of total series of 1180 patients with nontraumatic SAH* Diagnosis Cases No. Percent cerebral aneurysm cerebral AVM SAH (normal angiograms) * SAH = subarachnoid hemorrhage; AVM = arteriovenous malformation. TABLE 2 Analysis of 815 cases with ruptured cerebral aneurysms* Group for No. of Mortality Analysis Cases Rate (%) operative cases 613 early deaths early survivors 501 later deaths 70 30t survivors at 9-yr 431 follow-up review nonoperative cases 202 (154 in ES) early deaths 96 (76 in ES) 48 (49) early survivors 106 (78 in ES) later deaths 19 (of 78 in ES) 62t survivors at 9-yr 59 (of 154 in ES) follow-up review * Figures in parentheses indicate patients from the early series (ES). t Includes patients from both the early and late series. generally regarded as unsatisfactory treatment, and has been employed only when clipping was found to be too difficult. It was apparent early in the series that, in the presence of hypertension, wrapping alone was an imperfect operation. Clipping and wrapping were used as a combined procedure in relatively few cases. Craniotomy: Indirect Intervention. Placement of an anterior cerebral clip (Logue operation) was carried out for some difficult ACoA aneurysms in patients in whom the usual criteria for this indirect procedure were fulfilled. Trapping of ICA aneurysms was used in a very few patients, but never as the primary procedure of choice. Cervical Carotid Artery Ligation. Cervical ligation of the ICA was carried out as the procedure of choice in only 34 patients. It was reserved for large complex aneurysms of the ICA, in cases where direct intervention was judged to be difficult or even hazardous. Results of Treatment The results in the whole series of surgical and nonsurgical patients are summarized in Tables 2 to 10 and in Figs. 1 and 2. The significant results are discussed below. J. Neurosurg. / Volume 59 ~July,

3 R. H. Shephard TABLE 3 Outcome in nonoperative patients and reasons for not operating Reasons for Survivors Early Total Nonoperation Deaths Cases advanced age poor condition/severe neurolog ical deficits spasm on angiogram multiple aneurysms judged inoperable other subtotal incomplete information total cases Discussion Natural History of Ruptured Aneurysms Operative treatment of patients with ruptured cerebral aneurysms is now generally accepted as superior to conservative management; however, knowledge of the natural history remains incomplete. Most contributions on spontaneous SAH prior to the decade 1950 to 1960 preceded the routine adoption of angiography. Autopsies were performed on relatively few of the patients who died. Although the main causes of SAH were known, their relative occurrence was not, and all series contained an unknown number of patients with primary (parenchymatous) cerebral hemorrhage. Walton 24 reported a mortality rate from this "undifferentiated" SAH of 45% during the hospital admission following the first hemorrhage; he reviewed 11 series in addition to his own. These included those of Magee, ~3 Hamby, 6 and Hyland. 8 In all series, the etiology remained unknown in a large proportion of patients; thus, the cause remained obscure in 228 of Walton s 312 cases, and in 86 of Hamby s 130 patients. The more general adoption of cerebral angiography allowed confirmation of ruptured aneurysms (as predicted by Symonds 23) as the principal cause of SAH. Standards of comparison of surgical and nonsurgical treatment of ruptured aneurysms have been difficult to establish, for a variety of reasons. These include lack of understanding of the natural history, reporting on small selected series, incomplete follow-up review of survivors, and failure to record the total aneurysm population at risk and the fate of those patients not coming to operation. In addition, in some early series, pioneering surgical endeavors removed good-risk cases, compounding the difficulties of comparison. McKissock, et al., 14-~7,20 recognized early the problem of evaluating the management of aneurysm cases, and their series of papers between 1956 and 1966 went a long way toward establishing a baseline for comparison of surgical and nonsurgical treatment. They carried out several controlled trials of treatment. When patients unlikely to survive any definitive treatment were ex- cluded from the trials, these authors found a mortality rate of 41% for nonoperated patients during the first 6 months after the initial SAH. The surgical mortality during the same series of trials was 35%. If the patients excluded from the trial are considered, the overall mortality in over 900 patients was of the order of 42% during the first 6 months. Of a group of 364 conservatively managed patients in these trials, 213 were surviving 6 months after their initial SAH. The fate of these 213 survivors has been described by Winn, et al,25 during a long-term followup period of 20 years. During the first decade in this period, rebleeding occurred in an average of 3.5 % cases per year, the mortality rate from late rebleeds was 67%, and the mortality rate from rebleeding in the total 213 patients was 19%. The total number of deaths from hemorrhage in the 364 conservatively managed patients at 10 years after the initial incident was 186 (51% mortality). With the inclusion of 18 late deaths from other causes, the overall mortality was 56%. Locksley tt reported on 830 patients with single ruptured aneurysms admitted to the Cooperative Study and treated by nonsurgical methods. He found a 10% mortality rate on the 1st day, 5% on the 2nd, and 27% by the end of the 7th day; 15% died during the 2nd week and 59% by the end of 3 months. This mortality rate was among patients admitted to the series from which the surgical cases had been removed. The surgical mortality at 3 months was 35%, and the combined mortality rate was 37% in patients with single aneurysms. Pakarinen ~9 reported a mortality rate of 43% from the initial aneurysm rupture in untreated cases; a further 35% died during the 1st year after rupture. Surgical Versus Nonsurgical Results In the present series, among the 538 operative cases with single aneurysms, the mortality rate at 3 months was 16% (see Tables 4 and 5), and among the 164 nonoperative single-aneurysm cases it was 50%. The combined mortality rate in all 702 patients was 24%. The total group of 202 patients in the present series not submitted to operation (Table 3) was similar in composition to patients who were excluded from the trials of conservative and surgical treatment by McKissock, et al. 15 The largest number of nonoperative patients in the present study (77 cases) were in poor condition (Grades 4 or 5 of Botterell, et al., 3 or Category A of McKissock and Walsh ~7) and of these, 27 died within 5 days of admission. Some of the patients who were denied operation in the past would be considered for operation at the present time; for instance, some of the 20 in the poorcondition group might have undergone surgery following improvement to Botterell Grade 2 or 1. More patients with multiple aneurysms would qualify for operation now, and some of the 16 cases judged inoperable early in the series might be deemed operable with the recent improvements in surgical technique, anesthesia, and a greater understanding of cerebral physi- 8 J. Neurosurg./Volume 59/July, 1983

4 Prognosis of surgically treated aneurysms oiogy. 22 Sundt, et al, 2~ found that the presence of multiple aneurysms did not adversely affect their resuits. Sundt, et al., 2~ had an overall management mortality rate of 17% in 544 patients, including 78 who died before operation could be undertaken. This is a remarkable result, and may be compared with the 42% mortality rate at 6 months in the conservatively treated patients of McKissock, et al., J6 the 36% mortality rate at 3 months in conservatively managed patients in McKissock Category B ~7 as reported by Nishioka,18 and the 24% mortality rate for patients with single aneurysms at 3 months in the present series. By including deaths and complications prior to planned operation, Sundt, et al., 2~ hoped such correlation would place in perspective the risks of early surgery and serve as some standard for future comparison. It is in this spirit that the present series is presented. It is now possible to achieve an operability rate of over 70% (75% in this series but no less than 87% in the series of Sundt, et al.21). Future progress will lie in attempts to operate on an even greater percentage of patients, earlier diagnosis, more patients operated on after single hemorrhages, and developments in medical adjuncts permitting improvement from higher to lower neurological grades and so greater fitness for operation. Selection of Patients for Operation Selection of patients as suitable for operation was based on: 1) grading of patients condition and number of hemorrhages; 2) whether there were single or multiple aneurysms; 3) age; 4) concomitant disease; 5) the presence of hypertension; 6) computerized tomography (CT) findings; and 7) angiographic results. The manner in which these factors influenced selection of patients judged unsuitable for operation is shown in Table 3. In this table, the "others" included 14 with poor quality angiograms, five seen late after their last hemorrhage, four with anatomical anomalies, and three with concomitant disease. Of interest is the survival of fourfifths of those patients not operated on because of severe spasm displayed on the angiograms. Some improved greatly over the years, with diminution of hemiparesis, dysphasia, ataxia, and dysarthria. Grading of Patients" Condition and Number of Hemorrhages. The grading used in selection of patients for operation was patterned on the recommendations of Botterell, et al.; 3 that is, operations were performed on Grade 1, 2, and 3 patients. Many patients in Grade 3 had large hematomas, removal of which was considered to give the best chances of survival. As seen in Table 3, 77 patients were excluded from operation because of poor neurological condition (Botterell Grades 4 and 5). These included 14 who were too ill for angiography. In the earlier series, the presence or absence of significant intracranial hematoma (intracerebral or subdural) was documented on the patients index cards. Of TABLE 4 Effects of timing of surgery on patients with a single SAH and single aneurysm Timing of No. of No. of Mortality Operation* Cases Deaths Rate (%) > total cases * Number of days after subarachnoid hemorrhage (SAH). 464 patients with complete records in this respect, 108 had such hematomas; these 108 patients may be compared with those excluded from analysis by McKissock, el al, and considered as having a "mass effect" by Sundt, et al. 2~ The number of hemorrhages is so closely related to the patients condition and grading as to warrant discussion under the same subheading. I wish to stress particularly the influence on results of single and multiple hemorrhages, and single and multiple aneurysms. Table 4 shows the early results of operating on patients with single aneurysms who have had only a single hemorrhage at various times after the aneurysm rupture. The mortality rate of 13% for these 432 patients compares with 18 % for the total 613 patients who were operated on. It is apparent that 46% of the patients were operated on between the 2nd and 7th day after rupture and 90% before the 15th day. The mortality rate of 10% between the 2nd and 4th day is of interest in view of the predilection of many surgeons over a number of years to delay operation into the 2rid week, especially with antifibrinolytic therapy as an adjunct. Recently, however, there has been a trend toward earlier surgery. 7, ~ 2 Of the 77 patients with a single aneurysm and a single hemorrhage, who were operated on between the 2nd and 4th day, 50 were in Botterell Grade 1, 20 in Grade 2, and seven in Grade 3. 3 Disabilities and work capacity in this subgroup are referred to later in the Discussion. It is of further interest that operations on the 4th day (43 patients) carried a mortality rate of 7%, in stark contrast to 25% for 5th day operations and 19% in the second study period for the 5- to 7-day group. It can be concluded that, if operation cannot be undertaken by the 4th day, it is probably advisable to wait until after the 8th day, accepting the fact that there will be some deaths during the waiting period. The 163 patients operated on between the 8th and 15th day carried a mortality rate of 10% (Table 4). Locksley l~ found, in 830 patients treated by nonsurgical methods, that 11% of the original patients died between the 4th and 8th day; this represented 13% of those patients surviving at the 4th day. Probably adverse factors, such as spasm with ischemia leading to edema J. Neurosurg. / Volume 59 ~July,

5 R. H. Shephard TABLE 5 Effects of timing of surgery on patients with multiple hemorrhages and a single aneurysm Timing of No. of No. of Mortality Operation* Cases Deaths Rate (%) > total cases * Number of days after subarachnoid hemorrhage. and infarction, are more apparent during this period than either earlier or later, thus resulting in increased mortality (see Symon, 22 and Sundt, et al.2~). Table 5 presents the outcome in patients with a single aneurysm and multiple hemorrhages. The mortality rate of 25% was nearly twice that in patients with a single rupture. The reason for attempting to carry out operations before recurrent hemorrhage is immediately apparent from Tables 4 and 5. Also apparent is the inadvisability of operating before the 4th day after multiple aneurysm rupture. The mortality rate of 39% for this period is more than the natural mortality rate of 18%. 11 Whenever possible, a second or third hemorrhage was confirmed by lumbar puncture. On occasion, an incident thought to be a recurrent hemorrhage on clinical evidence was accepted as such even in the absence of confirmation by lumbar puncture. Such incidents occurring during the preoperative period carried the same poor prognosis as confirmed recurrent hemorrhages, and so were retained in the list of multiple hemorrhages. In those patients having either single or multiple hemorrhages, and in whom investigation was not completed until 4 weeks after SAH, surgery was not carried out. During the greater part of the 22-year period of the series, it was considered that the natural mortality in such patients was probably no greater than the surgical mortality. However, this policy has now been changed; in good-risk patients, surgery is performed up to several months after the aneurysm has ruptured. In patients with single aneurysms who have sustained multiple hemorrhages, probably the best time to operate is during the 2nd week after the last hemorrhage. Although the numbers are small, the mortality rate during this period was 15% as compared with 25 % for the patients with multiple hemorrhages as a whole. Locksley, ~1 in his analysis of 830 patients with single aneurysms managed by nonsurgical methods, reported a mortality rate of 42% as a result of second bleeding episodes. Single or Multiple Aneurysms. There was a higher early mortality rate after operation in patients with multiple aneurysms, whether after single or multiple rupture (Table 6). More patients with multiple aneurysms had multiple hemorrhages than did those with TABLE 6 Effect of multiple aneurysms on outcome No. of Hemorrhages No. of Cases No. of Deaths Mortality Rate (%) single multiple 20 l 0 50 total cases single aneurysms (30% and 20% respectively; see Tables 4, 5, and 6). This is almost certainly due to delay in diagnosis of the aneurysm that ruptured. This 3:2 ratio should decrease with the present policy of operating early: the approach is made to the aneurysm most likely to have ruptured, while the surgeon is prepared to clip other aneurysms if this appears reasonable. The operability rate for multiple aneurysm cases was 66% as compared with 76% for single aneurysms. In the surgical patients with multiple aneurysms, there were 34 early and later deaths. Of these patients, seven died from rupture of an aneurysm different from that causing the initial hemorrhage. This represents 11% of 62 surgical patients, compared with only 1.5% (eight of 551) of patients diagnosed and operated on for a single aneurysm, who died from rupture of a different aneurysm. So, in angiographically proven multiple aneurysm cases, there is a good argument for pursuing surgery on the unruptured aneurysms in addition to the ruptured lesion. This has long been the practice of several neurosurgeons, including Drake 5 and Sundt, et al. 21 Patients Age. Of the elderly patients not operated on (Table 3), 25 were over 65 years old and 10 (who had additional reasons for not undergoing surgery) were aged over 60 years. Of the 25 patients aged over 65 years, nine died early, but 16 survived to be followed for periods of 1 to 16 years (mean of 6 89 years). Only three died during that time, and the mean age at completion of follow-up review was 71 years. Concomitant Disease. Concomitant disease was severe enough to militate against operation in only three patients. Hypertension. It has long been known that hypertension adds to the risk of further rupture in patients with aneurysms and, therefore, is an added incentive to operate. In the present series, only very severe hypertension was accepted as a complete bar to operation. Milder states of hypertension were treated for a short time before craniotomy was carried out. Patients were regarded as being hypertensive if their blood pressure was above 150/100 mm Hg. In patients with several recordings, the lowest was employed for assessment. On this criterion, 45% of the operative and 56% of the nonoperative patients were hypertensive. Confirmatory evidence of hypertensive vascular disease, while often present, was not regarded as essential for diagnosis. 10 J. Neurosurg. / Volume 59 / July, 1983

6 Prognosis of surgically treated aneurysms FIG. 1. Outcome in the first 3 months after aneurysm rupture in the 613 operative and 202 nonoperative cases. Artiola i Fortuny and Prieto-Valiente L2 found a close relationship between hypertension and mortality and also between age and mortality, and this is true in the present series. Regarding pressures over 150/100 mm Hg as hypertensive, in patients under 50 years old, 240 were normotensive and had an early mortality rate of 7%, whereas in 137 patients with hypertension, the mortality rate was 19%. Over the age of 50 years, age was of greater significance than blood pressure: 28% of normotensive patients died early, compared to 26% of those with hypertension. Computerized Tomography Scanning. In recent years CT has been a factor in selection for surgery. In a few cases CT allowed differentiation between primary cerebral hemorrhage and primary SAH. However, in most cases, angiography has been required in addition to CT scanning. Although CT scanning usually requires supplementation by cerebral angiography for correct diagnosis of the presence and site of an aneurysm, CT is of value in establishing the prognosis of such patients. 4 Angiography. Ideally, to show all aneurysms, fourvessel angiography should be done in all patients. However, the risk of cerebral angiography, especially vertebral studies, in poor-risk and older subjects always needs careful consideration. In the present series, when other studies showed a ruptured anterior circle aneurysm and in patients over 50 years old, vertebral angiograms were not usually performed. Hence, the figure of 11% multiple aneurysms is less than the true occurrence, and less than reported in some other studies. Thus, Drake 5 found a 20% incidence and Locksley ~~ an 18.5% incidence of multiple aneurysms. Of 551 patients undergoing surgery for single aneurysms, eight (1.5%) died from rupture of a second aneurysm. Of these, four were later deaths, between 4 and 12 years after the first aneurysm had ruptured. Two of these had undergone second operations. Five of the eight had anterior circle aneurysms and in three the aneurysms were probably on the basilar artery; however, confirmation at autopsy was permitted in only one patient. Early Mortality The early mortality rate was derived from patients dying in the first 3 months. In surgical patients this included deaths from other causes as well as from operation. These data are shown in Tables 2 and 7 in operative cases and Table 2 in nonoperative cases; see also Fig. 1. Autopsies were performed on 80% of operative patients who died. Of the 43 operative patients who died as a result of hemorrhage (Table 7), 24 were judged to have had further rupture of the aneurysm operated on; 15 were confirmed at autopsy and two were confirmed at further operation, two appeared likely on clinical grounds, and five were suggested from the circumstances attending the operation. Of the confirmed aneurysm ruptures, eight aneurysms had been clipped inadequately, with J. Neurosurg. / Volume 59 / July,

7 R. H. Shephard TABLE 7 Causes of early death in 112 operative cases* Cause of Death No. of Cases hemorrhage 43 aneurysm under attack 24 different aneurysm 9 postoperative clot 5 other hemorrhage 5 cerebral infarction 36 pulmonary embolism 8 coronary thrombosis 4 ventricular fibrillation 3 bronchopneumonia 4 hypothalamic failure 2 perforated ulcer 1 meningitis 1 status asthmaticus 1 subtotal 103 incomplete information 9 total cases 112 * Early deaths occurred 3 months or less after aneurysm rupture. TABLE 8 Causes of later deaths in 61 operative cases Cause of Death No. of Cases hemorrhage 15 aneurysm under attack 4 different aneurysm 8 primary cerebral hemorrhage 3 other causes 43 coronary artery disease 14 bronchopneumonia 7 malignant disease 5 cerebral infarction 5 late effects of operation 4 epilepsy 2 asthma, diabetes, aortic aneurysm, 6 pulmonary embolism, drowning unknown 3 total cases 61 TABLE 9 Disabilities related to work capacity among 501 operation survivors Disability Work Capacity Normal Impaired third nerve palsy 8 4 epilepsy alone epilepsy with other disability 5 2 dysphasia alone 9 3 dysphasia & hemiparesis or hemiplegia 0 10 hemiparesis & hemiplegia paraparesis, quadriparesis 0 2 impaired vision 4 2 impaired memory 4 4 operation-related disability 0 5 akinetic tourism 0 4 dementia & psychiatric disorders 2 11 total cases definite slipping of the clip in four. Four patients were markedly hypertensive. In 22 of the operations involving early death, surgery was complicated by some difficulty. This included multilocular and other complex aneurysm formations, a large aneurysm size, the proximal location of some MCA aneurysms, and early operative rupture. Some aneurysms were broad-based, rendering clipping hazardous. In some, a distal (usually thinner) part was clipped, and a less certain wrapping procedure was carried out on the proximal, usually thicker-walled, base of the lesion. Spring-loaded clips were not available until Operations on the 24 patients involving rupture of the aneurysm under attack included carotid ligation in one; wrapping only in five; clipping and wrapping in four; clipping and ligation in one; and clipping only in 13. The clips were home-made tantalum clips (six), Scoville clips (10), and a Heifetz clip (one). There have been no proven cases of the clip having slipped in the last 7 years. The aneurysms were on the MCA in 11 patients, on the ACoA in seven, on the ICA in four, on the basilar artery in one, and on the pericauosal artery in one. This does not reflect the relative frequency of these aneurysms in the operated patients as a whole (see above). In three patients, the aneurysms were multiple as diagnosed angiographically; these came to autopsy with confirmation of further rupture of the aneurysm operated on. During the follow-up period, four patients died from proven further rupture of the aneurysm operated on. Two of those had been clipped and two wrapped. One patient died after incomplete investment of a basilar artery aneurysm 1 year after the operation, and one died 2 89 years after wrapping of a complex MCA aneurysm. Two patients with ICA aneurysms had small portions of the base of the aneurysrn left proximal to the clip. These developed into sizable aneurysms after 5 and 4 years, respectively, with ultimate rupture. Both patients were hypertensive (240/160 and 190/110 mm Hg) at the initial examinations. The early series includes 606 patients referred in the first period of 15 years of this study. There were 452 operative and 154 nonoperative cases in that group. All survivors of the 606 patients were followed for long periods, some for as long as 20 years. Of the 452 operated on, 369 survived and 308 were still alive at the end of the mean follow-up period of 9 years; that is, 68% of the initial number at risk. Observations on survivors with carotid ligation have been continued for rather longer (mean 11 years). Later Mortality Of the 369 early survivors of operation in the early series, 61 died after a mean follow-up period of 6 89 years. Their average age at death was 62 years. Table 8 lists the causes of these later deaths. In the 369 patients, the chance of dying from further 12 J. Neurosurg. / Volume 59 / July, 1983

8 Prognosis of surgically treated aneurysms FIG. 2. Later outcome among the 572 patients who survived the first 3 months after aneurysm rupture. rupture of the aneurysm operated on was only 1%, from a second aneurysm 2%, and from coincidental primary cerebral hemorrhage 1%. Exceeding all deaths from hemorrhage was the chance of dying from another condition (12%). The preponderance of unrelated conditions causing later mortality has been reported by others. 1,25,26 Inspection of Table 8 and Fig. 2 (fate of early survivors) confirms the protective value conferred by surgery on patients with ruptured aneurysms who survive the initial 3-month period. Such is also true concerning the 132 early survivors of the 161 operative cases in the second period of 7 years. Of necessity, however, these were observed for a shorter time span (mean 3 years). This protection against further rupture has been shown by others Of the 78 survivors without operation in the early series, 19 (24%) died during the follow-up period, the mean age at death being 61 years. Four patients died of further aneurysm rupture and nine from another known cause. The cause of death was not determined in six cases. Data concerning the long-term outcome of survivors are less prolific than communications on early management. Kaste and Troupp 9 reported on the long-term follow-up review of 178 patients with single aneurysms. These were randomly allocated for surgical or conservative treatment at approximately 7 weeks from the initial hemorrhage. During the mean follow-up period of 9 years, 16 of 92 conservatively managed patients and six of 86 surgical patients had fatal rebleeds. During the waiting period of 7 weeks, as admitted by the authors, the population at risk would change considerably due to a number of patients dying from further hemorrhage.ll While Yoshimoto, et a/., 26 were able to report a very low mortality rate (6%) in a series of 1000 surgically treated patients, they had a relatively short follow-up period (mean 3 years, 7 months). The results were described as excellent or good in over 730 patients, with 87% returning to normal life (64% of the initial number). The total aneurysm population at risk could not be stated in Kaste and Troupp s communication 9 and neither was it entirely clear in the series of Yoshimoto, et al. 26 In that series, Dr. Suzuki operated on 1000 of I080 patients, a remarkable achievement of 93% operability with but 6% mortality. Surgery was performed on 660 patients at some time after the 15th day, and the fate of the 80 not operated on is not stated. Disabilities. Work Capacity The term "work capacity" or "working capacity" has been used in preference to "employment" as a more inclusive term and indicating return to normality. It permits inclusion of schoolchildren too young to be employed, housewives, and retired persons. Men and women made redundant [laid off work] in our complex industrial society, outside the context of relevant illness, are also included under this term. Persons with impaired working capacity from disability were either unable to work at all or capable of light work only. Rather than discussing disabilities in isolation, a more realistic appraisal is their effect on working capacity (Tables 9 and 10). Many of the neurological disabilities were slight and did not impair work capacity. Disabilities and work capacity of the survivors of the 77 early operations (performed between the 2nd and 4th day; J. Neurosurg. / Volume 59 / July,

9 R. H. Shephard TABLE 10 Summary of disabilities among 501 operation survivors Summary of Work Capacity Disabilities Normal Impaired no disability neurological disability other disability 5 18 not stated 3 7 total cases (%) 376 (75%) 111 (22%) information incomplete 14 (2%) Table 4) on patients with a single aneurysm and a single hemorrhage compared favorably with the operation survivors as a whole. Sixteen patients (23% of the 69 survivors) had some neurological disability, mild in 11. Work capacity was normal in 78% of these 69 patients, compared with 76% in the 501 operation survivors as a whole. However, the 501 survivors included patients with a single aneurysm and multiple hemorrhages and those with multiple aneurysms. A better comparison is with survivors in the group of 163 patients with single aneurysms operated on between the 8th and 15th day after a single hemorrhage. Of this subgroup, 42 (27%)of the 147 survivors had some neurological disability, severe in 18. Nevertheless, 80% achieved a normal working capacity. Conclusions 1. Early operation (by the 4th day) is advised in good-risk patients after rupture of a single aneurysm. 2. Delayed operation (during the 2nd week after the last hemorrhage) is advised in good-risk patients after multiple aneurysm rupture. 3. The protective value of operation against further aneurysm rupture is confirmed by this communication. Of 613 patients operated on (75% of the number at risk), 501 or 82% survived the initial 3-month period. Of these, only 14 (3%) died later from a ruptured aneurysm. 4. While work capacity was impaired by neurological disability in 16%, it was, nevertheless, normal in 376 or 75% of the 501 patients surviving operation and in 61% of the initial population at risk. Acknowledgments My thanks are gladly given to my wife for much diligent work in collation of the data and to Mrs. C. Murray for secretarial assistance. References I. Artiola i Fortuny L, Prieto-Valiente L: Long-term prognosis in surgically treated intracranial aneurysms. Part t: Mortality. J Neurosurg 54:26-34, Artiola i Fortuny L, Prieto-Valiente L: Long-term prognosis in surgically treated intracranial aneurysms. Part 2: Morbidity. J Neurosurg 54:35-43, Botterell EH, Lougheed WM, Scott JW, et al: Hypothermia, and interruption of carotid, or carotid and vertebral circulation, in the surgical management of intracranial aneurysms. J Neurosurg 13:1-42, Davis JM, Davis KR, Crowell RM: Subarachnoid haemorrhage secondary to ruptured intracranial aneurysm: prognostic significance of cranial CT. A JR 134: , Drake CG: On the surgical treatment ofintracranial aneurysms. Ann R Coil Phys Surg Can 11: , Hamby WB: Spontaneous subarachnoid haemorrhage of aneurysmal origin. Factors influencing prognosis. JAMA 136: , Hugenholtz H, Elgie RG: Considerations in early surgery on good-risk patients with ruptured intracranial aneurysms. J Neurosurg 56: , Hyland HH: Prognosis in spontaneous subarachnoid hemorrhage. Arch Neurol Psychiatry 63:61-78, Kaste M, Troupp HL: Subarachnoid hemorrhage: longterm follow-up results of late surgical versus conservative treatment. Br Med J 1: , Locksley HB: Report on the Cooperative Study of Intracranial Aneurysms and Subarachnoid Hemorrhage. Section V, Part I. Natural history of subarachnoid hemorrhage, intracranial aneurysms and arteriovenous malformations. Based on 6368 cases in the Cooperative Study. J Neurosurg 25: , Locksley HB: Report on the Cooperative Study of Intracranial Aneurysms and Subarachnoid Hemorrhage. Section V, Part II. Natural history of subarachnoid hemorrhage, intracranial aneurysms and arteriovenous malformations. Based on 6368 cases in the Cooperative Study. J Neurosurg 25: , Ljunggren B, Brandt L, KAgstr6m E, et al: Results of early operations for ruptured aneurysms. J Neurosnrg 54: , Magee CG: Spontaneous subarachnoid haemorrhage. A review of 150 cases. Lancet 2: , McKissock W, Paine KWE, Walsh LS:" An analysis of the results of treatment of ruptured intracranial aneurysms. Report of 772 consecutive cases. J Neurosurg 17: , McKissock W, Richardson A, Walsh L: Anterior communicating aneurysms. A trial of conservative and surgical treatment. Lancet 1: , McKissock W, Richardson A, Walsh L: "Posterior communicating" aneurysms. A controlled trial of the conservative and surgical treatment of ruptured aneurysms of the internal carotid artery at or near the point of origin of the posterior communicating artery. Lancet 1: , McKissock W, Walsh L: Subarachnoid haemorrhage due to intracranial aneurysms. Results of treatment of 249 verified cases. Br Med J 2: , Nishioka H: Report on the Cooperative Study of Intracranial Aneurysms and Subarachnoid Hemorrhage. Section VII, Part 1. Evaluation of the conservative management of ruptured intracranial aneurysms. J Neurosurg 25: , Pakarinen S: Incidence, aetiology, and prognosis of primary subarachnoid haemorrhage. A study based on 589 cases diagnosed in a defined urban population during a defined period. Acta Neurol Scand 43 (Suppl 29):1-128, J. Neurosurg. / Volume 59 ~July, 1983

10 Prognosis of surgically treated aneurysms 20. Richardson AE, Jane JA, Yashon D: Prognostic factors in the untreated course of posterior communicating aneurysms. Arch Neurol 14: , Sundt TM Jr, Kobayashi S, Fode NC, et al: Results and complications of surgical management of 809 intracranial aneurysms in 722 cases. Related and unrelated to grade of patient, type of aneurysm, and timing of surgery. J Neurosurg 56: , Symon L: Disordered cerebro-vascular physiology in aneurysmal subaracbnoid haemorrhage. Acta Neurochir 41:7-22, Symonds CP: Spontaneous subarachnoid haemorrhage. Q J Med 18:93-122, Walton JN: Subaraehnoid Haemorrhage. Edinburgh/ London: E & S Livingstone, 1956, 350 pp 25. Winn HR, Richardson AE, Jane JA: The long-term prognosis in untreated cerebral aneurysms: I. The incidence of late hemorrhage in cerebral aneurysm: a 10-year evaluation of 364 patients. Ann Neurol 1: , Yoshimoto T, Uchida K, Kaneko U, et al: An analysis of follow-up results of 1000 intracranial saccular aneurysms with definitive surgical treatment. J Neurosurg 50: , 1979 Manuscript received September 20, Accepted in final form January 13, Address reprint requests to: Reginald H. Shepbard, F.R.C.S., Trent Regional Department of Neurosurgery, Derbyshire Royal Infirmary, London Road, Derby, DE1 2QY, England. J. Neurosurg. / Volume 5 9 / July,