Clinico-statistical study on morphological risk factors of middle cerebral artery aneurysms.

Influences of various factors on postoperative outcome of 122 well-documented cases, out of a total of 151 cases of middle cerebral artery aneurysm, are discussed in this paper. The shape of the aneurysm, major axis, major axis/neck and major/minor axis ratio were correlated with the presence or absence of a bleb (p < 0.0000001), and indicated a correlation not only between aneurysmal shape and the outcome (p < 0.05) but also between preoperative seriousness and the outcome (p < 0.05). The preoperative seriousness and the grade of subarachnoid haemorrhage indicated a close correlation between each of these two parameters and the outcome (p < 0.000001 for each). Both the quantity and the colour of CSF outflow from the chiasmal cistern showed close correlation with vasospasm (p < 0.01), onset of hydrocephalus (p < 0.01) and the outcome (p < 0.001). Moreover, vasospasm and hydrocephalus grade itself also showed close correlation with the outcome (p < 0.001 and p < 0.00001). All parameters: blood pressure grade, BPmax, BPmin, BP fluctuation showed correlations not only with preoperative seriousness (p < 0.001) and the outcome (p < 0.0001) but also with subarachnoid haemorrhage frequency, number of aneurysms, and major axis/neck ratio. [ABSTRACT FROM AUTHOR]