Our modification of Botterell's classification3 has been applied to 275 consecutive cases of intracranial aneurysm treated by the faculty and resident staff of the Ohio State University and affiliated hospitals over a 12-year period (Table 1).
|Grade I||Asymptomatic, or minimal headache and slight nuchal rigidity.|
|Grade II||Moderate to severe headache, nuchal rigidity, no neurological deficit other than cranial nerve palsy.|
|Grade III||Drowsiness, confusion, or mild focal deficit.|
|Grade IV||Stupor, moderate to severe hemiparesis, possibly early decerebrate rigidity and vegetative disturbances.|
|Grade V||Deep coma, decerebrate rigidity, moribund appearance.|
Serious systemic disease such as hypertension, diabetes, severe arteriosclerosis, chronic pulmonary disease, and severe vasospasm seen on arteriography, result in placement of the patient in the next less favorable category.
In this series, almost all cases were graded at admission and again just prior to operation. It is recognized that such classifications are arbitrary and that the margins between categories may be ill defined. We are, nevertheless, of the opinion that a fairly sharp differentiation is possible among patients who have few or no meningeal signs, patients who have well-defined meningeal signs but no neurological deficit, and patients who show neurological malfunction. Associated disease was sufficient to change the graded risk when it was unequivocally present and, in the judgment of the surgeon, severe enough to influence the patient's operative or postoperative course. We did not consider it necessary for the patient to have recovered completely from all symptoms and signs of the hemorrhage to be considered an optimal or Grade I risk.
Table 2 shows the relative distribution of cases upon admission, classified according to this method. The largest single group of patients were those classified as Grade II, and the second largest group were those classified as Grade III.
Assuming that neurological deficit indicates arterial spasm, ischemia, and brain edema and that under such conditions the intracranial contents are more vulnerable to manipulation, and then further assuming that patients without neurological deficit would be best able to tolerate surgery, we established the following policy with regard to operation.
First, patients graded I and II were taken to surgery as soon as a diagnosis could be made, preferably within 24 hours of admission. Second, with two exceptions, patients graded III or below were treated conservatively until they improved to Grade I or II.
The first exception was that patients who had multiple, repeated, bleeding episodes were operated upon at Grade III or lower; the second was that patients who appeared to have an intracranial hematoma threatening life were operated upon at once and the hematoma evacuated, with or without definitive repair of the aneurysm.
Obviously, with our criteria, serious systemic disease or marked vasospasm will delay operation. However, neither the patient's age nor the site of the aneurysm are used in determining the grade of risk. Furthermore, the number of days elapsed since the last hemorrhage is not considered relevant. Figure 1 shows that the majority of good risk patients were operated upon within 3 weeks of their last hemorrhage, many in less than 1 week.
This paper represents a retrospective analysis of the results of the policies described above.
BotterellE. H.LougheedW. M.ScottJ. W.VandewaterS. L. Hypothermia, and interruption of carotid, or carotid and vertebral circulation, in the surgical management of intracranial aneurysmsJ. Neurosurg.195613:1–42.BotterellLougheedScottVandewaterJ. Neurosurg.13:1–42.