Table 2

Patients with electrophysiological changes and/or new postoperative neurological deficits

Patient age	Aneurysm locations	EP change	Time from event to EP change	Intervention	Time to resolution	Neurological change
34	R superior hypophyseal, 5 mm	60% decrease in SSEP	4 min	Clip repositioned	Complete resolution in 3 minutes	None
47	L P-com, 6 mm	60% decrease in SSEP	5 min	Clip repositioned	Complete resolution in 16 minutes	None
47	R P-com, 15 mm	100% decrease in SSEP	10 min	Clip repositioned	Complete resolution in 14 minutes	None
57	R P-com, 3 mm; R ICA, 10mm; R MCA, 15 mm	55% decrease in left SSEP; 39% decrease in right SSEP	15 min	Increased MAP	Complete resolution in 9 minutes	None
49	L PICA, 10 mm	50% decrease in SSEP	5 min	Temporary clip removed	Complete resolution in 5 minutes	None
38	R P-com, 18 mm; R ICA, 15 mm	50% decrease in SSEP	17 min	Increased MAP	Complete resolution in 26 minutes	None
51	A-com, 35 mm	60% decrease in SSEP bilateral	12 min	Increased MAP	Complete resolution in 12 minutes	None
34	L MCA, 7 mm	70% decrease in SSEP	5 min	Retractor adjusted	Complete resolution in 4 minutes	None
		60% decrease in SSEP	3 min	Clip repositioned	Complete resolution in 3 minutes
48	Basilar, 10 mm	100% decrease in SSEP bilateral	3 min	Increased MAP	50% recovery in 52 minutes; persistent change	Dead
60	L MCA, 25 mm	60% decrease in SSEP	5 min	Temporary clip removed	Complete resolution in 10 minutes	None
48	A-com, 22 mm	65% decrease in SSEP (right)	8 min	Temporary clip removed	Complete resolution in 18 minutes	None
57	L vertebral, 20 mm	Delayed left BAEP, waves III-V	7 min	Temporary clip removed	Partial recovery in 5 minutes; complete recovery in 60 minutes	None
61	R MCA, 7 mm; 3 R P1 segment aneurysms (2-3 mm)	100% decrease in SSEP	5 min	Clip repositioned	Complete resolution in 59 minutes	Dead
		100% decrease in SSEP	32 min	Clip repositioned	Complete resolution in 16 minutes
		R BAEP waves delayed	8 min	Increased MAP	Persistent wave V delay (occured during closure)
47	Vertebral-basilar junction, 10 mm	50% decrease in SSEP (left)	12 min	Increased MAP	Complete resolution in 30 minutes	None
		50% decrease in BAEP (right)	8 min	Increased MAP	Complete resolution in 16 minutes

All electrophysiological changes are cortical potentials and correspond to the same side of the brain as the aneurysm in question, except where indicated; SSEP=somatosensory evoked potential; BAEP=brainstem auditory evoked potential; EP=electrophysiological; R=right; L=left; MCA=middle cerebral artery; ICA= internal cerebral artery; P-com=posterior communicating artery; PICA=posterior inferior cerebral artery; A-com=anterior communicating artery.