The International Cooperative Study on the Timing of Aneurysm Surgery. Part 2: Surgical results

Initial and recurrent bleeding are the major causes of death following subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The goal of this study was to determine the causes of mortality and morbidity after subarachnoid hemorrhage.

METHODS

We identified all first-ever spontaneous subarachnoid hemorrhages that occurred in the nearly 1.3 million population of greater Cincinnati during 1988.

RESULTS

Thirty-day mortality for subarachnoid hemorrhage was 45% (36 of 80 cases). Of the 36 deaths, 22 (61%) died within 2 days of onset; 21 of these deaths were due to the initial hemorrhage, and one death was due to rebleeding documented by computer tomography. Nine of the remaining 14 deaths after day 2 were caused by the initial hemorrhage (2 cases) or rebleeding (7 cases). Volume of subarachnoid hemorrhage was a powerful predictor of 30-day morality (P = .0001). Only 3 of the 29 patients with a volume of subarachnoid hemorrhage of 15 cm3 or less died before 30 days. Two of these 3 patients died from documented rebleeding; the third had 87 cm3 of additional intraventricular hemorrhage. Delayed arterial vasospasm contributed to only 2 of all 36 deaths.

CONCLUSIONS

Most deaths after subarachnoid hemorrhage occur very rapidly and are due to the initial hemorrhage. Rebleeding is the most important preventable cause of death in hospitalized patients. In a large representative metropolitan population, delayed arterial vasospasm plays a very minor role in mortality caused by subarachnoid hemorrhage.

Early surgery for ruptured vertebrobasilar aneurysms

The authors present a series of 1767 patients with aneurysms of the vertebrobasilar circulation, most of whom were operated on 14 days or more following their last subarachnoid hemorrhage (SAH). Since 1970, 206 patients with vertebrobasilar aneurysms have been surgically treated within 7 days after their last SAH (day of SAH = Day 0). Of patients with a good preoperative grade (Botterell Grade 1 or 2), a good or excellent outcome was obtained in 80% during the first postsurgical month, irrespective of the timing of surgery. All except one of the Grade 5 patients died, and 70% of the Grade 4 patients were significantly disabled or dead. The overall operative mortality rate was the same whether surgery took place in the 1st week after SAH or was delayed. The frequency of rupture of the aneurysm during early surgery was not higher than during late surgery. Thirteen percent of patients developed a delayed ischemic neurological deficit as a consequence of reactive arterial narrowing (vasospasm). The authors recommend early surgery for patients with a good preoperative grade, whose aneurysm does not present a particular technical difficulty because of size, configuration, or location, and occasionally in patients whose lives appear to be in jeopardy because of recurrent hemorrhage.

Phosphorus-31 magnetic resonance spectra reveal prolonged intracellular acidosis in the brain following subarachnoid hemorrhage

Subarachnoid hemorrhage may be complicated by cerebral ischemia which, though reversible initially, can progress to an irreversible neurological deficit. 31P magnetic resonance spectroscopy, which can determine intracellular pH and thus detect areas of ischemia noninvasively, was applied to 10 patients on 30 occasions, at various times after subarachnoid hemorrhage. In 5 of them, there were focal areas of the brain in which the intracellular pH was reduced to < 6.8 compared with the normal range of 7.05 +/- 0.05. Consciousness was impaired in 4 of these patients. Repeat studies in these 4 patients showed that intracellular pH remained abnormally low for several days but eventually returned toward normal. The return of intracellular pH to normal paralleled an improvement in clinical condition in each case. In the fifth patient with lowered regions of intracellular pH, there had been an impaired level of consciousness and a transient focal deficit prior to the single study. In the other 5 patients there were no areas of reduced pHi even though in 3 of them there was intraventricular or cisternal blood shown on brain computerized tomography. In 2 of these 3 patients there were no abnormal neurological signs at the time of the magnetic resonance study. The third patient had a dense and persistent hemiparesis. The remaining two patients had no abnormal neurological signs at any stage. We suggest that the areas of acidosis may reflect ischemia which is potentially reversible. Since the technique is noninvasive, sequential 31P magnetic resonance spectroscopy of the brain offers a method of detecting cerebral ischemia and, more importantly, of assessing methods of treatment.

Aneurysmal bleeding. A plea for early surgery in good-risk patients

From 1985 onwards we have aimed at operating on good-risk patients, i.e., those graded I-III on the WFNS SAH Scale, within 3 days after the aneurysmal bleed. We report on a series of 100 consecutive operations for saccular aneurysm, covering a period of 5 1/2 years. Early operations (in the above sense) were done in 57 good-risk but otherwise unselected patients. After a one year follow-up, 47 of them (82%) were found to have made a good recovery (Glasgow Outcome Score I). The outcome of (mostly early) surgery in 15 selected poor-risk patients (WFNS SAH Scale IV and V) was much less favourable. Late surgery (4 or more days after SAH) was performed in 28 good-risk patients, most of whom had been admitted several days or weeks after the bleeding. Almost all of these patients had a good outcome. It is argued that the known management results of delayed surgery, which during the deliberately chosen interval exposes the patient to the risk of rebleeding and vasospasm, have by now been surpassed by those of early surgery. However excellent the surgical results of delayed operations may be, early operation should become the treatment of choice in good-risk patients.

The effect of surgery on the severity of vasospasm

Intracranial aneurysm surgery performed between 4 and 12 days after subarachnoid hemorrhage (SAH) has been associated with an increased risk of delayed cerebral ischemia and poor outcome compared to surgery performed before or after this time. To investigate whether this increased risk is due to aggravation of vasospasm, the angiograms obtained before and after surgery in 56 patients operated on at various times after aneurysmal SAH were studied. Vasospasm was quantitated by measuring the diameters of intracranial arteries and expressed as the ratio of the diameters of the intracranial arteries to the diameter of the extracranial internal carotid artery. Aggressive surgical clot removal was not performed at surgery. To correct for differences in prognostic factors for vasospasm between patients operated on at different times after SAH, multiple regression analysis was performed using the arterial diameter ratio during vasospasm as the dependent variable and the prognostic factors for vasospasm, including the time of surgery, as independent variables. Equations predicting the severity of vasospasm could be generated using the clinical grade on admission, patient age, and preoperative arterial diameter ratio. The time of surgery had no effect on vasospasm. Cerebral infarction due to vasospasm developed in five (15%) of 34 patients operated on within 3 days after SAH and in four (20%) of 20 operated on between 4 and 12 days after SAH (p = 0.66). A good outcome for these two groups was achieved in 88% and 85%, respectively (p = 1.00). These results suggest that the timing of surgery does not affect the development of vasospasm. Any increased risk of cerebral ischemia associated with surgery performed between 4 and 12 days after SAH is due to factors other than aggravation of vasospasm.

Endovascular treatment of intracranial aneurysms

OBJECTIVE

To examine the techniques, reported experiences, and advantages and disadvantages associated with the endovascular treatment of intracranial aneurysms.

DESIGN

We review the endovascular techniques used for the treatment of intracranial aneurysms and the sequelae of subarachnoid hemorrhage, which have evolved during the past 10 years.

MATERIAL AND METHODS

Two broad categories of endovascular therapy for intracranial aneurysms are described: occlusion of the parent artery and preservation of the parent artery by selective occlusion of the aneurysm with balloons or metallic coils. The Mayo protocol for testing tolerance of patients before permanent balloon occlusion of the parent artery is described, as are the types of aneurysms most amenable to this treatment. In addition, use of balloon angioplasty for cerebral vasospasm after subarachnoid hemorrhage is reviewed.

RESULTS

Recent improvements in microcatheter technology have facilitated the safe navigation of percutaneously introduced catheters in the intracranial circulation and selective catheterization of intracranial aneurysms. Surgically difficult aneurysms are now being treated with endovascular techniques more frequently than in the past. Early results from animal experiments and human trials have shown that selective occlusion of aneurysms with metallic coils may have a role in the treatment of intracranial aneurysms. Balloon angioplasty of symptomatic cerebral vasospasm has demonstrated improvement in neurologic function in approximately 70% of patients.

CONCLUSION

As technology continues to improve and as greater experience is obtained, interventional neuroradiologists will continue to have an increasingly important role in the treatment of intracranial aneurysms.

The incidence and treatment of asymptomatic, unruptured cerebral aneurysms

The importance of early detection by various radiological techniques of asymptomatic, unruptured aneurysms as a means of preventing subarachnoid hemorrhage (SAH) is discussed in this report. Four hundred volunteers underwent clinical and radiological evaluations between March, 1988, and September, 1992. Studies included a neurological examination as well as digital subtraction cerebral angiography via a femoral arterial catheter, computerized tomography, T1- and T2-weighted magnetic resonance (MR) imaging of the whole brain, and MR angiography. The evaluation revealed 27 asymptomatic, unruptured intracranial aneurysms in 26 volunteers, for an incidence of 6.5%. The subjects ranged in age from 39 to 71 years, with an average of 55 years. The aneurysms were located on the internal carotid artery in 13 cases (48%), the anterior communicating artery in six (22%), the middle cerebral artery in six (22%), and the basilar artery in two (7%). Aneurysms ranged in size from 5 mm or less in 16 cases, 6 to 10 mm in nine, and 11 to 15 mm in one; one aneurysm was more than 15 mm, with a maximum diameter of 2 cm. Volunteers with a family history of SAH within the second degree of consanguinity showed a higher incidence of aneurysms (17.9%). Aneurysm clipping was performed on 20 of the 26 cases with no significant morbidity or mortality. These findings support the contention that aggressive early detection of unruptured aneurysms may improve the outcome in patients harboring cerebral aneurysms by preventing the devastating effects of SAH.

Ruptured intracranial aneurysms--learning from experience

The outcome of treatment of 400 consecutive patients with ruptured intracranial aneurysms was assessed at 1 year. The patients were treated by a single surgeon over a period of 13 years. Data sheets completed as each patient was treated included a contemporary analysis of the reasons for any unsatisfactory outcome. Surgery was usually delayed for over 10 days from the last haemorrhage. Over the four successive 100-patient cohorts, in which the composition of the patient population remained unaltered, 1 year overall management mortality fell steadily from 38 to 24%. One year surgical mortality fell from 19 to 3%. The population of those operated on who were in Glasgow Outcome Score 5 at 1 year rose from 73 to 90% (from 51 to 71% for all patients). Of the 123 deaths, 89 occurred prior to operation, 24 after it. Thirty-five patients died from rebleeding prior to operation, but only eight of these occurred in patients judged fit for surgery at the time. All but one of the postoperative deaths resulted from technical problems related to the surgery. Over the successive cohorts, several factors indicated an improvement in operative efficiency, notably a fall in the proportion of cases with technical problems from 15 to 1%. We have demonstrated a steady improvement in management results, resulting largely from increasing operative experience. We do not believe that changes in overall management strategy, such as early surgery, would have any effect on overall outcome.

Management and long-term outcome following subarachnoid haemorrhage and intracranial aneurysm surgery in elderly patients: an audit of 199 consecutive cases

To address the question of managing subarachnoid haemorrhage (SAH) in the older patient, the management and outcome of 199 consecutive patients aged > or = 60 years with a confirmed diagnosis of subarachnoid haemorrhage (n = 186) or an unruptured intracranial aneurysm (n = 13) were reviewed. In seven patients, the cause of the SAH was an arterio-venous malformation and these were excluded from further analysis. Angiography was performed in 141 patients with a complication rate of 2.1%. Angiography was not performed in 51 patients and, in this cohort, the in-patient mortality rate was 68.6% and only 27.5% had a favourable outcome at discharge. Operation was not performed in 21 patients with demonstrated aneurysms for a variety of reasons. In this group, the in-patient mortality rate was 47.6% and 38.1% had a favourable outcome at discharge. Eighty-one patients in good neurological grade underwent surgery for a ruptured aneurysm and six patients underwent surgery for a symptomatic unruptured aneurysm. The surgical mortality was 1.1% and a favourable outcome at discharge was achieved in 83.9% of patients. Thirty-three patients were angiographic negative and there was a favourable outcome in 97% of this group. The management mortality in these selected patients admitted to the Department of Clinical Neurosciences was 24.4% and a favourable outcome was recorded in 66.2% of patients. Long-term follow-up (median 40 months, range 3-120 months) was obtained in 97% of discharged patients. The probability of survival at 60 months for patients in good condition at discharge was 0.826 (95% confidence interval 0.722-0.894).(ABSTRACT TRUNCATED AT 250 WORDS)

[Anesthesia in surgery for intracranial aneurysms]

The two major neurological complications of subarachnoid haemorrhage (SAH) due to an intracranial aneurysm are rebleeding and delayed cerebral ischaemia related to cerebral vasospasm. The best way to prevent rebleeding is early surgery. Even when surgery is performed within the first 72 hours posthaemorrhage, the risk of cerebral ischaemia due to vasospasm is high. Conventional medical treatment of cerebral vasospasm includes haemodilution, hypervolaemia and increase of arterial blood pressure. Haemodilution is of limited value as the patients suffering from SAH have usually a low haematocrit. The effectiveness of hypervolaemia is controversial and it may worsen cerebral and pulmonary oedema. Systemic hypertension is an effective therapy of vasospasm, but which can only be used once the aneurysm is controlled. Nimodipine and nicardipine, two calcium antagonists, have a beneficial effect on neurologic outcome following SAH. Today, it is still debated whether the beneficial effect of nimodipine results from the vascular effect of the drug or from a direct cerebral cytoprotective mechanism. Early surgery implies that surgeons operate on brains in acute inflammatory state. Thus, it is mandatory to use peroperative techniques improving cerebral exposure. These techniques include infusion of mannitol, lumbar cerebrospinal fluid (CSF) drainage, administration of anaesthetic agents known to decrease cerebral blood flow (CBF) and hypocapnia. Usually, the effect of CSF drainage is very effective and sufficient by itself. The second objective in the peroperative period is to avoid ischaemia. In areas with decreased flow distal to vasospasm, autoregulation is impaired and CBF is directly dependent on cerebral perfusion pressure. Furthermore, the safe practice of transient clipping of vessels supplying the aneurysm has dramatically reduced the indications of controlled hypotension. During temporary clipping, some authors recommend a pharmacological brain protection using barbiturates, etomidate or propofol, but this practice has not been validated by randomized studies. However, it is generally agreed that the arterial pressure should be increased during temporary clipping to improve collateral blood flow and to maintain it after the aneurysm has been secured. To conclude, together with lumbar CSF drainage and transient clipping, the anaesthetic management of the patients should include: maintenance of the arterial blood pressure close to its preoperative level, maintenance of PaCO2 between 30 and 35 mmHg and of normovolaemia through replacement of fluid and blood losses. After completion of surgery, recovery from anaesthesia should be rapid to allow fast diagnosis of neurological complications. The monitoring of the status of consciousness is the key of the diagnosis of early postoperative complications.

[Subarachnoid hemorrhage: cerebral damage, fluid balance, intracranial pressure and pressure-volume relation]

Changes in osmolality and electrolyte concentrations are observed frequently in patients with subarachnoid haemorrhage (SAH). Intracranial pressure (ICP) plays a determinant role in the development of secondary brain damage following SAH and may be caused by haemorrhage itself, oedema formation and disturbance of cerebrospinal fluid (CSF) dynamics. The relationships among these factors are the aim of this investigation. In 17 comatose SAH patients, ICP was monitored through a ventricular catheter; serial of pressure-volume index (PVI) and CSF formation and reabsorption were performed. Arterio-jugular differences for oxygen and lactate were measured. The average ICP recorded for each 12 hour interval was 18.9 mmHg (SD = 5.9); mean cerebral perfusion pressure (CPP) was 75 mmHg (SD = 13); the lowest CPP value was 30 mmHg. Mean PVI was 22.7 mL (SD = 7.4), ranging from 5 to 36. Eleven patients however, showed a PVI less than 15 mL at some point during testing. Values of CSF dynamics indicated disturbances of CSF reabsorption in 11 cases. When the cause of ICP rise was identified in CSF disturbances, treatment was successful, even in case of reduced PVI. Mean C(a-v)O2, corrected for a PaCO2 of 40 mmHg, was 3.7 mL.dL-1 (SD = 1.1) ranging from the extremely low value of 0.2 to 6.8 mL.L-1. Three patients with extremely low C(a-v)O2 values showed a cerebral production of lactate and developed areas of ischaemia on the CT scan. Hyponatraemia, considered as a sodium plasma concentration of less than 135 mmol.L-1, was detected in seven patients. Hyponatraemia was treated by infusion of hypertonic sodium solutions. Mannitol (1 g.kg-1.d-1 in four doses) was infused if the sodium plasma concentration was not corrected by the former treatment or if ICP exceeded 20 mmHg. Treatment was aimed at preserving cerebral perfusion by providing adequate pre-load, low viscosity (Ht 30%) and sustained arterial pressure. Correction of hyponatraemia was therefore achieved more through hypertonic fluids infusion than by using diuretics.

Impact of early surgery on outcome after aneurysmal subarachnoid hemorrhage. A population-based study

BACKGROUND AND PURPOSE

Population-based patient materials have not been used earlier in assessing the effects of neurosurgical treatment on survival and functional outcome of subarachnoid hemorrhage. Moreover, the proportion of all subarachnoid hemorrhage patients who might be candidates for neurosurgical treatment has not been estimated.

METHODS

We compared the survival and functional outcome of two population-based patient materials from Central Finland in 1976 through 1978 (n = 146) and 1980 through 1987 (n = 351). The most important basic characteristics of both materials were similar. In the 1970s, only patients aged < 60 years with carotid territory aneurysms were operated on after an interval of 2 weeks from the bleeding. In the 1980s, early surgery was attempted, and the other exclusion criteria were abandoned. Allocation to medical or surgical treatment was not randomized.

RESULTS

During the 1970s, only 14% of the patients had surgical treatment, with a median delay of 15 days after the bleeding; in the 1980s, the corresponding figures were 46% and 4 days. Despite these fundamental changes in the treatment policy, the survival up to 3 years in the 1980s was only marginally improved compared with the 1970s. Conversely, the functional outcome at 4 years after the bleeding was significantly better in the 1980s than the 1970s, with 82% and 64% of the survivors, respectively, being independent in the activities of daily living (P = .002). We estimated that 60% of all patients with subarachnoid hemorrhage might be candidates for neurosurgical treatment, provided that there are no delays in admission or evaluation.

CONCLUSIONS

An active treatment policy of subarachnoid hemorrhage including early surgery only marginally improves survival, but the quality of life of the survivors is significantly better. Only 60% of all patients in the population with subarachnoid hemorrhage can, at least theoretically, benefit from surgical treatment.

Causes of morbidity and mortality, with special reference to surgical complications, after early aneurysm operation: a prospective, one-year study from neurosurgical units in Sweden

In the present prospective study, 6.93 of Sweden's 8.59 million inhabitants (81%) were covered by the five participating centres. All patients with verified aneurysmal SAH admitted between June 1, 1989 and May 31, 1990, were enrolled. Basically, all participating centres have the same management protocol for SAH victims, including ultra-early referral to a neurosurgical unit, followed by pan-angiography and surgery as early as logistically possible. In this presentation, 145 patients who preoperatively were in Hunt & Hess Grades I-III and who underwent surgery for a supratentorial aneurysm within 72 h after the bleed, are evaluated. Eighty-one % (117 patients) made a good recovery. The morbidity was 12% (17 patients) and the mortality 7% (11 patients). The most common cause of unfavorable outcome was surgical complications, which accounted for 8% of the total series (12 patients). A subanalysis of these cases did reveal a positive correlation to higher age and more severe SAH on CAT scan.

Does a safe size-limit exist for unruptured intracranial aneurysms?

Of 1076 patients with intracranial ruptured aneurysms (RA) included in the Danish Aneurysm Study, 948 had the RA verified by angiography. Of these cases 908 RA had a maximum diameter less than 25 mm. 162 RA were < 5 mm, 474 and 272 were between 5-10 mm and 11-24 mm, respectively. The average diameter of the RA according to the day of angiography after the aneurysm rupture did not differ significantly within the first 10 days. In these circumstances, using this indirect method for estimation of aneurysm rupture according to the size, we also recommend that unruptured aneurysms with a size 10 mm or less should be seriously considered for operation.

A clinical study of the relationship of timing to outcome of surgery for ruptured cerebral aneurysms. A retrospective analysis of 1622 cases

Between 1980 and 1987, 1622 patients with angiographically verified ruptured cerebral aneurysms were admitted within 7 days after subarachnoid hemorrhage. A retrospective analysis evaluated both the timing of surgery in operative patients and the status of nonsurgical patients. The patients' clinical grade according to the Hunt and Hess classification was assessed at admission, and a comparative analysis of outcome was carried out for each grade in relation to time of surgery: those operated on from Day 0 to 3 and those undergoing surgery on Day 4 or later. Among nonsurgical cases, fatal rebleeding occurred in 105 cases and fatal vasospasm in 69 cases. These nonsurgical cases were divided into one of two groups, either an early- or a late-management group, and the outcome of each group was analyzed by clinical grade. The mortality rates in the early-surgery groups were higher than in the late-surgery groups, especially in Grade V, in which the rate was significantly different. However, with the 174 nonsurgical patients included in these management results, marked differences in mortality rates disappeared except in Grade V, which failed to show statistical significance. A higher rate of good recovery among Grade III patients receiving early surgery shifted significantly in the early-management group. The results suggest that the timing of surgery in clinical Grade I or II patients is not a major factor; however, early surgery appears to be beneficial in Grade III and IV patients. The incidence of rebleeding in the early- and late-management groups was 2.7% and 9.5%, respectively.

Subarachnoid hemorrhage without detectable aneurysm. A review of the causes

BACKGROUND

In 15% to 20% of patients with a spontaneous subarachnoid hemorrhage, no aneurysm is found on the first angiogram. This review emphasizes that this group of patients is in fact heterogeneous and describes the clinical features, pattern of hemorrhage on early computed tomographic (CT) scan, prognosis, and proposed management in the several and distinct subsets of these patients.

SUMMARY OF REVIEW

Patients in whom no aneurysm is revealed on the initial angiogram can be subdivided mainly according to the pattern of hemorrhage on an early CT scan. In two thirds of these patients the CT scan shows a perimesencephalic pattern of hemorrhage (ie, blood confined to the cisterns around the midbrain); these patients invariably have a good prognosis, which obviates the need for a second angiogram. Patients with diffuse or anteriorly located blood on CT scan are at risk of rebleeding. In most of these patients the source of hemorrhage is an occult aneurysm, but intracranial artery dissections, dural arteriovenous malformations, mycotic aneurysms, trauma, bleeding disorders, substance abuse, or a cervical origin of the hemorrhage should also be considered. Patients with no blood revealed on an early CT scan but with xanthochromic cerebrospinal fluid are extremely rare. These patients deserve a second reading of the scan for blood in the prepontine cistern, which can be the only site of hemorrhage in perimesencephalic hemorrhage.

CONCLUSIONS

The prognosis and management of patients in whom no aneurysm is found on the initial angiogram depends on the pattern of hemorrhage on the initial CT scan. Patients should no longer be designated with the umbrella term "angiogram-negative subarachnoid hemorrhage."

Emergent aneurysm clipping without angiography in the moribund patient with intracerebral hemorrhage: the use of infusion computed tomography scans

The authors report their experience with 25 patients (mean age, 44.3 +/- 12.1 years) with an intracerebral hematoma (ICH) from a ruptured aneurysm who were emergently operated on without angiography. Instead, preoperative high-resolution infusion computed tomography (CT) scans were used to identify the aneurysm causing the hemorrhage. In all patients, the preoperative Glasgow Coma Scale score was < 5 and brain stem compression was evident. ICH was present in the frontal or temporal lobe and was often associated with intraventricular hemorrhage (n = 17) and significant (> 1 cm) midline shift (n = 18). Infusion CT scans correctly identified the aneurysm in all patients (middle cerebral artery, 18; posterior communicating artery, 2; carotid bifurcation, 3; anterior communicating artery, 2). Partial evacuation of the hematoma guided by infusion CT scan was usually required first to clip the aneurysm definitively using standard microvascular techniques. Intraoperative rupture occurred twice, and temporary clips were used on four occasions. Lobectomy (n = 8), decompressive craniotomy (n = 15), and ventriculostomy (n = 8) were required to control cerebral swelling. All patients underwent postoperative angiography to confirm aneurysm obliteration. Eleven unruptured aneurysms were subsequently identified. Nine had been predicted by infusion scan. Twelve patients survived, eight of whom were only moderately disabled and were independent at 6-months' follow-up. Of the 13 patients who died, all except one died within 4 days of admission. The authors conclude that although angiographic verification before aneurysm surgery is preferable, in the moribund patient with intracerebral hemorrhage, infusion CT scanning provides sufficient information concerning vascular anatomy to allow rational emergency craniotomy and aneurysm clipping.

Visual loss and a suprasellar mass complicated by pregnancy

A 43-year-old woman who was 12 weeks pregnant presented with a one-month history of visual loss in the right eye. Neuroimaging studies revealed multiple intracranial aneurysms, one of which compressed the right optic nerve. Her pregnancy raised many issues concerning her management. Evidence of aneurysm enlargement and the increased risk of aneurysm rupture as gestation progressed led to early, successful surgical intervention.

Selective endovascular treatment of 71 intracranial aneurysms with platinum coils

Seventy-one intracranial aneurysms were treated by endovascular techniques, with the placement of minicoils inside the aneurysmal sac. Most aneurysms were manifest by hemorrhage (67 cases), and 43 of these were treated within the first 3 days after presentation. At the 1-year follow-up examination, the outcome was scored as good in 84.5% of cases, but the morbidity and mortality rates were 4.2% and 11.3%, respectively. Twenty-nine aneurysms in the anterior circulation and 42 in the posterior circulation were treated. In this series, 23 patients were classified as Hunt and Hess neurological Grade I, 27 as Grade II, 12 as Grade III, nine as Grade IV, and none as Grade V. Thirty-three aneurysms were less than 10 mm in diameter, 28 were 10 to 25 mm, and 10 were larger than 25 mm. The preliminary results from this study appear to justify the emergency treatment of aneurysms by this approach. Aneurysms in the posterior circulation are particularly well suited for this type of surgery.

One-year outcome in early aneurysm surgery: prediction of outcome

Predictors of one-year outcome were studied in patients treated for ruptured intracranial aneurysm. A total of 929 patients, who were treated conservatively or surgically, and 839 patients as a part of this population who were surgically treated, were randomly divided into two groups in order to create predictive models by logistic regression and to validate them. The models were derived from two-thirds of these two patient groups and the remaining one-thirds were used for validation. The pre-operative variables of both conservatively and surgically treated patients were studied by Model A. The pre-operative Grade (Hunt and Hess), age, and the presence of vasospasm on angiography were the three most important predictors of the one-year outcome (Glasgow Outcome Scale 1-2/3-5). Model B consisted of pre- and per-operative, and Model C pre-, per-, and post-operative variables collected from the surgically treated group. The pre-operative Grade, ligation of a major vessel and age were the three most powerful determinants of outcome in Model B. In Model C high Grade, post-operative CT-hypodensities and ligation of a major vessel were most closely associated with poor outcome. Model A, based on pre-operative data, most accurately predicted good outcome. All the 59 patients in the validation sample (n = 310) who were predicted to have a less than 5% probability of poor outcome had a favourable outcome (positive and negative predictive value 100%). Model C determined that 22 of 280 patients would have a more than 80% probability of poor outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

One-year outcome in early aneurysm surgery: a 14 years experience

In a consecutive series of 1150 patients with cerebral aneurysms diagnosed in our department by angiography or autopsy between the years 1977-1990, 1007 patients underwent definitive operative treatment of their aneurysms mainly by early surgery. More than half (55%) were operated on during the first three days after subarachnoid haemorrhage (SAH), and more than three quarters (77%) during the first week. The surgical mortality at 30 days was 9%; at one-year follow-up 13% had died. The total management mortality was 22%. The 618 patients presenting in Hunt and Hess Grades I-II had a 4% mortality, and 90% had an independent life at follow-up; 270 Grade III patients had a 19% mortality and 68% were independent. There were 99 patients operated on in Grades IV-V with a 46% mortality and 30% were independent. Age of the patient and size of the aneurysm were strongly related to outcome; however, many of the giant aneurysms were operated on as an emergency because of large intracerebral haematomas. Best results were obtained in the anterior communicating artery (ACA) area; the lowest rate of useful recoveries was in the vertebro-basilar artery (VBA) area (71%). Early surgery did not prevent delayed ischaemic deficits. During the first 72 hours patients in Grades I-III can be operated on safely with good results. The results in Grades IV-V are poor, and we suggest that only cases with large haematomas or considerable hydrocephalus or those improving should be operated on in the first days after SAH, with limited hopes of functional recovery.

[Surgical treatment of intracranial aneurysms: comparison between early and late surgery]

The clinical course of patients with subarachnoid hemorrhage (SAH) due to rupture of cerebral aneurysm admitted during the last five years is analysed: 157 patients were treated by direct surgical approach of the aneurysm, 58 localized in the anterior communicating artery (ACoA), 48 in the internal carotid artery (ICA), 43 in the middle cerebral artery (MCA), and 8 in the posterior circulation. Fourty-four patients were operated on during the first 72 hours (early surgery), 40 during the 4th and 7th days, 16 during the 8th and the 10th, and 57 after the 10th (late surgery). According to main localizations, the outcome of patients with aneurysms in the ACoA was good in 79.1%, in the ICA in 69.7%, and in the MCA in 69.7%. Patients treated in Hunt & Hess grade I and II had both good results in 77.5%, grade III patients had good results in 71.3%, and grade IV in 56.2%. According to timing of surgery good results were observed in 61.4% for patients submitted to early surgery, in 80% for patients treated during the 4th and 7th days, in 81.2% for patients treated during the 8th and the 10th days, and in 70.2% for that submitted to late surgery. The overall mortality was 14.6%. For grade I patients mortality was 6.4%, for grade II was 12.2%, for grade III was 15.2%, for grade IV was 25%, and all patients operated on in grade V died.(ABSTRACT TRUNCATED AT 250 WORDS)

A simple scoring system for accurate prediction of outcome within four days of a subarachnoid haemorrhage

This study was designed to examine the consistency of a number of easily identifiable predictive factors in assessing outcome within four days of a subarachnoid haemorrhage. Patients with a proven subarachnoid haemorrhage, aged between 15-65, of any neurological grade who had bled within 72 hours of admission, and who had undergone a CT scan within 96 hours of the ictus, were included. Three groups of patients were studied prospectively. The studies were separated in time and place. The series were similar overall but there were some variations between the three groups of patients because of alterations in referral patterns and management strategies between the series. There were significant differences in the patients' ages, grades on admission, timing of angiography, negative angiography rate and timing of operation. This did not affect overall outcome; 57%, 61% and 59% of the patients in series 1, 2 and 3 respectively making a good recovery. The proportion of patients with a poor outcome was also similar. To identify the level of risk of an individual patient within the first few days of haemorrhage, we considered a number of early predictive factors. Two emerged as strong predictors of outcome; the early neurological grade and the distribution of blood on the CT scan. We developed a simple scoring system from the first series, based on these findings, designed to predict outcome at three months. The scoring system was calculated on the basis of the distribution of blood seen on the CT scan and the patients' neurological grade on admission. Two points each were scored for interhemispheric, intraventricular, basal or intracerebral blood (excluding blood in the sylvian fissures). Patients in grade 1-3 scored -1, grade 4 scored 0, grades 5 & 6 scored +5. The scan score and grade score were summated to give the overall score. Patients were placed in risk groups (low, score -1; medium, score 0-2; high, score 3+). The scoring system was then applied prospectively to the two subsequent groups of patients. In each of the three series there was a clear correlation between the patients' scores and their outcomes but more importantly the probability of each outcome for each risk group was considered. In both the second and third series the probability of a full recovery in the low risk group was very likely--P = 0.000.(ABSTRACT TRUNCATED AT 400 WORDS)

Vertebro-basilar aneurysms: does delayed surgery represent the best surgical strategy?

The appropriate time to perform surgery for posterior circulation aneurysms is debated. Controversy exists secondary to the lack of information regarding the overall management and outcome, as well as difficulties with their surgical treatment and infrequent occurrence. The present study examines the results of 46 patients with ruptured vertebro-basilar aneurysms treated with a delayed surgical protocol. Twenty-four were Hunt-Hess grade I/II on admission, 13 were grade III, and 9 grade IV/V. Nineteen patients (40%) (4 grade I/II, 6 grade III, and the 9 grade IV/V on admission) died before meeting the required conditions for surgery. Causes of death were vasospasm (8 cases), direct effect of the initial bleeding (7 cases), and rebleeding (4 cases). Surgical results were excellent/good in 87% of the patients. Surgical mortality was 8% (2 out of 24). In this study, despite encouraging surgical results, overall mortality was disappointingly high. We suggest that as more experience is gained in treating vertebrobasilar aneurysms, early surgery should be performed in selected cases. Early surgery is prophylactic for rebleeding and allows for more aggressive treatment of cerebral vasospasm.

Selective angiography for early aneurysm detection in acute subarachnoid haemorrhage

In a consecutive series of 312 surgical aneurysm cases more than 90% of the patients reached neurosurgical expertise within 48 hours from bleeding. Computed tomography permitted prediction of the assumed rupture site based on blood clot location in the majority (86%) of cases. This target vascular territory was usually investigated by selective angiography and in 9 out of 10 patients an aneurysm, ultimately shown to be the correct source of bleeding, was demonstrated. In 14% of the cases the source of bleeding could not be established thus calling for complete four vessel studies. It is concluded that limited angiographic studies are compatible with preserving a high surgical standard in cases unequivocally exhibiting a localizing clot pattern on the CT scan. Though suboptimal in a general sense, incomplete vascular studies, if four vessel angiography is not obtainable without delay or risk, should not delay earliest possible clipping of ruptured aneurysms to avoid the devastating effects of recurrent bleeds.

Use of transcranial Doppler sonography to predict development of a delayed ischemic deficit after subarachnoid hemorrhage

Blood flow velocity was recorded from the middle or anterior cerebral and extracranial internal carotid arteries using transcranial Doppler sonography (TCD) in 121 unselected consecutive patients with acute aneurysmal subarachnoid hemorrhage (SAH). Recordings were made daily or every 2nd day after SAH for a 14-day period. The highest recorded velocity was greater in the 47 patients who developed a delayed ischemic neurological deficit (186 +/- 6 cm sec-1; mean +/- standard error of the mean) than in the 74 patients who did not develop a neurological deficit (149 +/- 5 cm sec-1) (p < 0.001, Mann-Whitney test). Peak velocity recordings can thus assist in the diagnosis of delayed ischemic neurological deficit; however, peak velocity was often recorded only after the onset of neurological deficit. When only those readings made before the onset of neurological deficit were considered, there was no significant difference in peak velocity between the groups (157 +/- 8 cm sec-1 vs. 149 +/- 5 cm sec-1, respectively). Alternative TCD parameters for predicting delayed neurological deficit were therefore sought. The rate of increase in TCD velocity, recorded during the first few days after SAH, was significantly higher in the patients who later developed a neurological deficit. A maximum velocity increase of 65 +/- 5 cm sec-1 per 24-hour period was recorded in patients who later developed a neurological deficit, compared to 47 +/- 3 cm sec-1 24 hrs-1 in patients who did not develop a delayed neurological deficit (p = 0.003). A rise of more than 50 cm sec-1 24 hrs-1 identifies those patients who are most likely to develop a delayed ischemic neurological deficit after SAH. This can be applied prospectively to individual cases. Serial TCD studies in the early period after SAH are thus of value to identify patients who can be selected for prophylactic therapy, which may prevent or ameliorate development of delayed ischemic neurological deficits.

Intracerebral hemorrhage more than twice as common as subarachnoid hemorrhage

The authors report a study of all instances of spontaneous intracerebral hemorrhage (ICH) (188 cases) and subarachnoid hemorrhage (SAH) (80 cases) that occurred in the Greater Cincinnati area during 1988. Adjusted for age, sex, and race, the annual incidence of ICH was 15 per 100,000 population (95% confidence interval 13 to 17) versus six per 100,000 for SAH (95% confidence interval 5 to 8). The incidence of ICH was at least double that of SAH for women, men, and whites and approximately 1 1/2 times that for blacks. The 30-day mortality rate of 44% for ICH was not significantly different from the 46% mortality rate for SAH. Despite the evidence that ICH is more than twice as common and the disorder just as deadly as SAH, clinical and laboratory research continues to focus primarily on SAH.

Effect of systemic hypotension on cerebral energy metabolism during chronic cerebral vasospasm in primates

The influence of systemic hypotension on cerebral blood flow (CBF) and energy metabolism during chronic cerebral vasospasm after subarachnoid hemorrhage was studied in 15 monkeys. Changes in the phosphorus spectrum, as demonstrated by in vivo phosphorus-31 (31P) magnetic resonance (MR) spectroscopy, or in regional CBF were measured in the parietal cortex during graded hypotension. Sequential changes in the phosphorus spectrum were observed during moderate hypotension in the animals 7 days after the introduction of an autologous blood clot around the right middle cerebral artery (MCA). Angiograms revealed a reduction in vessel caliber by approximately 50% in the right MCA. The mean CBF in the spasm side decreased in parallel with a decrease in the mean arterial blood pressure (MABP) from 120 to 40 mm Hg, indicating the abolition of autoregulation. There were no significant differences in the mean percentage totals of inorganic phosphate (Pi), phosphocreatine (PCr), adenosine triphosphate (ATP), and pH between the hemispheres at baseline MABP before hypotension. The values of PCr, ATP, and pH decreased significantly (p < 0.05) and Pi increased significantly (p < 0.05) at an MABP of less than 60 mm Hg in the involved hemisphere. The ratio of PCr:Pi decreased in parallel with a decrease in MABP. The ATP showed a stepwise decrease during moderate hypotension (MABP 60 mm Hg) and was reduced significantly 20 minutes after the beginning of hypotension (p < 0.05). The results indicate that, during chronic vasospasm, changes in cerebral energy metabolism are coupled with changes in CBF in the state of impaired autoregulation. There exists a critical level for ischemia below which high-energy phosphorus metabolites become markedly depleted. It is suggested that 31P MR spectroscopy may be useful to evaluate the ischemic vulnerability of brain tissue in order to prevent delayed neurological deficit during cerebral vasospasm.

Management outcome for vertebrobasilar artery aneurysms by early surgery

Treatment of vertebrobasilar artery aneurysms remains fraught with complications, even in the present era of microneurosurgery. In a series of 1150 consecutive patients with cerebral aneurysms from a defined catchment area with 870,000 inhabitants, 93 with vertebrobasilar artery aneurysms were treated by two surgeons during a 14-year period. Sixty-three patients had surgery, 36 during the first week after bleeding. There was no surgical mortality among 33 good grade patients. Nine (14%) of the 63 surgical cases had died at 1 year. Forty-nine (53%) of the total group of 93 patients were functioning independently at 1 year. Overall management mortality was 37%. All 11 patients admitted in Grade V died. In spite of improvements in surgical techniques, we are far from achieving ideal results. Early diagnosis and surgery before rupture are urgently needed. Arteriosclerotic giant aneurysms remain untreatable.

Levels of catecholamine in plasma and cerebrospinal fluid in aneurysmal subarachnoid hemorrhage

Despite intensive investigation into the cause of cerebral vasospasm (focal ischemic deficit) after subarachnoid hemorrhage, the morbidity and mortality associated with this condition remain high. Various studies have shown levels of catecholamine in plasma and cerebrospinal fluid (CSF) to be increased in subarachnoid hemorrhage, and it is possible that these vasoactive substances play an important role in the subsequent vasospasm. In an attempt to elucidate this possibility, the study presented here was undertaken to investigate the relationship between catecholamine levels in plasma and CSF and focal ischemic deficit (FID); the rupture of aneurysms on blood vessels supplying the hypothalamus as compared with the rupture of aneurysms on blood vessels supplying other areas of the brain; and the clinical outcome of the patients. Concentrations of adrenaline and noradrenaline in plasma and CSF samples obtained from 21 patients who had suffered aneurysmal subarachnoid hemorrhage were determined by a radioenzymatic technique. Significantly higher levels of adrenaline were found at the time of surgery in the CSF of patients with FID. A similar trend, though not statistically significant, was also observed for plasma. Patients with a rupture of aneurysms on blood vessels supplying the hypothalamus showed a tendency towards higher catecholamine levels in plasma and CSF. Subjects with a bad clinical outcome (i.e., those who were severely disabled or had died) had significantly higher levels of catecholamine in plasma than did those with a good clinical outcome (i.e., those with moderate or no disability). Further detailed analysis of the interrelationships showed that, within the group of patients with FID, those with rupture of aneurysms on blood vessels supplying the hypothalamus had significantly higher catecholamine levels in plasma than did those with rupture of aneurysms on other cerebral vessels. Furthermore, in the group of patients with rupture of aneurysms on blood vessels supplying the hypothalamus, those with a bad clinical outcome had significantly higher catecholamine levels in plasma than did those with a good clinical outcome. These findings lend support to the possibility that damage to the hypothalamus and subsequent elevations in catecholamine levels may be associated with FID and poor clinical outcome.

Overall outcome in aneurysmal subarachnoid hemorrhage. A prospective study from neurosurgical units in Sweden during a 1-year period

The present prospective study, with participation of five of the six neurosurgical centers in Sweden, was conducted to evaluate the overall management results in patients with aneurysmal subarachnoid hemorrhage (SAH). The participating centers covered 6.93 million (81%) of Sweden's 8.59 million inhabitants. All patients with verified aneurysmal SAH admitted between June 1, 1989, and May 31, 1990, were included in this prospective study. A uniform management protocol was adopted involving ultra-early referral, earliest possible surgery, and aggressive anti-ischemic treatment. A total of 325 patients were admitted during the study period, 69% within 24 hours after hemorrhage. On admission, the patients were graded according to the scale of Hunt and Hess: 43 patients (13%) were classified in Grade I, 119 (37%) in Grade II, 53 (16%) in Grade III, 76 (23%) in Grade IV, and 34 (11%) in Grade V. Nimodipine was administered to 269 of the 325 patients: intravenously in 218, orally in 15, and intravenously followed by orally in 36. At follow-up examination 3 to 6 months after SAH, 183 patients (56%) were classified as having made a good neurological recovery, 73 patients (23%) suffered some morbidity, and 69 (21%) were dead. Surgery was performed in 276 (85%) of the patients; emergency surgery with evacuation of an associated intracerebral hematoma was carried out in 30 patients. Early surgery (within 72 hours after SAH) was performed in 170 individuals, intermediate surgery (between Days 4 and 6 post-SAH) in 29 patients, and late surgery (Day 7 or later after SAH) in 47 individuals. Of 145 patients with supratentorial aneurysms who were preoperatively in Hunt and Hess Grades I to III and who were treated within 72 hours, 81% made a good recovery; in 5.5% of patients, the unfavorable outcome was ascribed to delayed ischemia. It is concluded that, among patients with all clinical grades and aneurysmal locations, almost six of 10 SAH victims referred to a neurosurgical unit can be saved and can recover to a normal life.

Surgical management of unruptured intracranial aneurysms. Personal experience with 37 cases and discussion of the indications

The authors report a series of 37 cases of unruptured aneurysms, admitted and operated upon over a 5 year period (1985-1990), which represents an incidence of 18% of the total number of aneurysm patients operated upon during this period. These unruptured aneurysms were discovered in 4 types of circumstances: 1) Associated with a ruptured aneurysm but treated in a second procedure (9 cases); 2) After a transient ischaemic attack (6 cases); 3) After a cerebral haemorrhage of a different origin (3 cases), 4) After the onset of various neurological symptoms other than SAH (19 cases). Giant aneurysms (over 2.5 cm in diameter) are excluded from this series. Overall these 37 patients harboured 52 aneurysms, and 1 patient was operated upon on both sides. 27 aneurysms (52%) were located on the right side, 15 (29%) on the left side, and 10 (19%) on the midline. In the immediate post operative period, 1 patient died (2.6%) and 8 patients (21%) presented various complications. The outcome at 6 months was: death 2.6%, moderately disabled 8%, good recovery 89%. The arguments in favour of, or against, the surgical treatment of unruptured aneurysms are discussed in view of the literature. In favour of prophylactic surgery are: 1) The rather poor overall outcome following aneurysm rupture (including deaths before admission); 2) The rather good outcome of surgery in published series of unruptured aneurysms. The data of the natural history of the unruptured aneurysm are more questionable: in this view, surgery seems to be recommended in young patients with an easily accessible aneurysm and being in a good clinical condition.(ABSTRACT TRUNCATED AT 250 WORDS)

The International Cooperative Study on the Timing of Aneurysm Surgery. The North American experience

BACKGROUND AND PURPOSE

The timing of aneurysm surgery after subarachnoid hemorrhage is a major neurosurgical controversy addressed by the International Cooperative Study on the Timing of Aneurysm Surgery (1980-1983). The present report examines the results of this trial in the subgroup of patients admitted to North American centers.

METHODS

The method of study was a large, multicenter, prospective, epidemiological survey. Neurosurgeons were required to indicate prospectively the interval to planned aneurysm surgery at the time of patient admission. Outcome at 6 months was determined by a blinded evaluator, and overall management results were analyzed by the planned surgical interval.

RESULTS

Seven hundred seventy-two (21.9% of the total study population) patients admitted from days 0 to 3 after subarachnoid hemorrhage were accrued in North American centers. Overall outcome in patients planned for surgery in days 0-3 was equivalent in terms of mortality (after adjustment for prognostic variables) to patients planned for days 11-32, but the early patients had significantly improved rates of good recovery (70.9% versus 61.7%, p less than 0.01). Patients planned for surgery during the days 7-10 interval had nearly twice the mortality of patients in the other intervals.

CONCLUSIONS

In contrast to the results from the overall trial, which found no difference between early and delayed surgery, results were best in North American centers when surgery was planned between days 0 and 3 after subarachnoid hemorrhage. These findings argue strongly for early diagnosis and referral for surgical intervention of North American patients suspected of having a ruptured cerebral aneurysm.

Minor leak before rupture of an intracranial aneurysm and subarachnoid hemorrhage of unknown etiology

Of 312 consecutive patients who were admitted to an emergency hospital because of subarachnoid hemorrhage (SAH), data on premonitory minor leaks were available on 303. Patients with an aneurysmal SAH had significantly (P less than 0.05) more frequently (100 of 273, or 37%) a history of symptoms consistent with a previous minor leak than those with a hemorrhage of unknown etiology (4 of 30, or 13%). Aneurysmal SAH was associated with a poorer prognosis, more frequent occurrence of repeated bleeding and cerebral ischemia compared with SAH of unknown etiology, even in the good grade patients. The possible occurrence of a minor leak in poor grade patients may be even more frequent because the history obtained from family members was quite often uncertain. The outcome did not differ according to the evidence of previous minor leaks, but those who were admitted before a major rupture had a good outcome. The median time between a minor leak and major rupture was 14 days (range, 1 day to 4 mo). The correct diagnosis of a minor leak is important because early diagnosis and management can improve the overall outcome of this disastrous disease.