A review of the entire series shows that in 84 cases the aneurysm had not ruptured, whilst in 89 the lesion had not been revealed by angiography in our department (Table 1). Since angiographic localisation of the aneurysm is an essential prerequisite to definitive surgery these 173 cases must be excluded, leaving 599 for detailed analysis. Cases in which treatment was conservative must naturally fulfil the same criterion.
|Aneurysm not shown by angiography||39||37|
|Aneurysm shown by angiography||599||220||37|
The distribution of the 599 aneurysms in relation to the vessel of origin is shown in Table 2 which agrees closely with the distribution of all ruptured intracranial aneurysms however diagnosed.
|Site of Aneurysm||Number||Percentage|
|Anterior cerebral-anterior communicating||174||29|
|Internal carotid-posterior communicating||165||28|
|Bifurcation of internal carotid||51||8|
|Peripheral anterior cerebral||15||2|
|Posterior cerebral and vertebral system||19||3|
Since it is the long-term results of the operative procedures that is of the greatest interest, the analysis is made on the information available at the latest follow up. The period of observation varies from over 10 years to less than 6 months and is given in detail in Table 3. Only 2 per cent of patients were lost in follow up and 90 per cent of the remainder have been under observation for the whole of the time since their discharge.
|Length of Follow Up||Treatment|
|Conservative (No. of Patients)||Surgical (No. of Patients)|
|Less than 6 mos.||1||8|
In assessing the patients at the time of this review, patients in “full work” were those who had returned to their former employment or to one financially equivalent even though they may have shown some neurological deficit, the “partially disabled” were those working but in a lesser capacity than formerly, whilst the “totally disabled” were out of work. Some of these latter patients were severely disabled physically or mentally but there were a small number who, although apparently fit for work, refused to undertake it. Since this was probably because of a change in mental attitude following their haemorrhage it was right to consider them as totally disabled. All deaths were included irrespective of cause and time (Table 4).
|Site of Aneurysm||Conservative Treatment||Operative Treatment|
|Total||Deaths %||Full Work||Part. Disabil.||Total Disabil.||Not Known||Total||Deaths %||Full Work||Part. Disabil.||Total Disabil.||Not Known|
|Anterior cerebral-anterior communicating||62||32 (52%)||25||1||4||0||112||46 (41%)||46||8||12||0|
|Internal carotid-posterior communicating||31||15 (48%)||15||0||0||1||134||33 (25%)||72||13||11||5|
|Middle cerebral||16||8 (50%)||8||0||0||0||85||27 (32%)||40||7||9||2|
|Peripheral anterior cerebral||3||2 (66%)||1||0||0||0||12||2 (16%)||5||1||3||1|
|Bifurcation of internal carotid||7||3 (43%)||3||0||1||0||44||18 (41%)||17||6||3||0|
|Multiple aneurysms||40||16 (40%)||15||5||4||0||34||12(35%)||14||4||2||2|
|Other sites||11||5 (45%)||5||0||0||1||8||1 (12%)||6||0||1||0|
|Total||170||81 (47%)||72||6||9||2||429||139 (33%)||200||39||41||10|
It is seen that the mortality in the conservatively treated group is higher than in the group operated upon, the percentage of conservatively treated patients who return to full work is lower, but that more of the surgically treated patients are partially or totally disabled. This may well be an expression of the ability of surgery to save the lives of some patients with brains severely damaged by their haemorrhage.
The lack of follow up in 2 conservatively treated and 10 surgically treated patients does not affect the comparison of mortality since if all these patients were considered as dead the difference in mortality would be the same.
Nor does the cause of death affect the comparison as 4 conservatively treated and 7 surgically treated patients died from causes not related to their aneurysm or to the operation, and if these are excluded from the mortality figures the difference between conservatively and surgically treated groups remains the same. Only the crude death rate, therefore, need be considered.
Table 4 also shows that the comparisons are similar when considered in relation to the site of the aneurysms.
Time of Death. Table 5 shows that 74 per cent of all deaths in the conservatively treated group occurred within 1 month of admission and 72 per cent of the total deaths in the surgical group within 1 month of operation. Eleven per cent of the conservatively treated and 7 per cent of the surgically treated patients who survived 6 months, died later.
|Time||Conservatively Treated (Time after Admission)||Surgically Treated (Time after Operation)|
|Less than 1 mo.||60||100|
Cause of Death. Forty-one conservatively treated patients died from the effects of the haemorrhage requiring their admission to our unit, 36 from a recurrent haemorrhage and 4 from causes not related to their aneurysm (aortic stenosis and cardiac failure in 1, coronary thrombosis in 1 and cerebral atherosclerosis in 2).
Eighty surgically treated patients died from the effects of their haemorrhage or of the operation which was performed, 50 from a recurrent haemorrhage and 7 from causes not related to their aneurysm (cerebral atherosclerosis in 2, cancer in 2, bacterial endocarditis in 1, coronary thrombosis in 2) whilst the cause of death was not known in the other 2.
The 50 deaths from recurrent haemorrhage after operation (12 per cent) were studied further. Forty-five patients had a further haemorrhage after carotid ligation and 38 of these died. There is no doubt that the pathologist's interpretation of the age of the haemorrhage in some of these patients who died within a few days of their operation may have been incorrect, and that they died from infarction of the cerebral hemisphere. Thirteen patients had a further bleeding after a definitive craniotomy and 10 of these died (proximal anterior cerebral clip—6; muscle wrapping—2; clipping of aneurysm—1; trapping—1). Two of the 3 patients who had a further haemorrhage after simple aspiration of an intracerebral haematoma died.
Nature of Operation. Table 6 shows that 417 (97 per cent) of the operative procedures were ones which it was hoped would prevent further rupture of the aneurysm. Exploratory operations should be considered as surgical failures whilst the miscellaneous group, usually simple aspiration of a haematoma through a burr-hole, were more or less despairing measures to save the patient's life.
The material for this paper was collected and analysed during the tenure of a Research Fellowship awarded by The Board of Governors of St. George's Hospital, to whom our thanks are due.