Correlation between central somatosensory conduction time, blood flow velocity, and delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

Abstract

In this retrospective study of 67 aneurysmal patients, the predictive role of central conduction time (CCT) on vasospasm occurrence evaluated by means of transcranial Doppler sonography (TCD) and the correlation of CCT to blood flow velocity measured simultaneously in postoperative course were studied. Data about the clinical state of patients at the time of admission (Hunt Hess scale), severity of subarachnoidal hemorrhage on initial CT scan (Fisher grade), timing of surgery (acute or delayed), outcome (Glasgow Outcome Scale), severity of vasospasm graded by highest mean blood flow velocity (BFV) during the entire clinical course and CCT values measured at admission (preoperatively), then postoperatively (one day after surgery) and simultaneously with later TCD investigations were collected from the files. Interhemispheric difference of CCT was also calculated. The results showed that CCT at admission was not predictive for vasospasm. CCT measured either at admission or on the first postoperative day did not differ significantly in the different grades of vasospasm. Similar results were obtained in the acute and in the late operated group of patients. The results also suggest that increased CCT and interhemispheric difference at the time of admission indicate a worse prognosis, but this can be related to higher surgical risk rather than to a higher incidence of late ischemic deterioration. Simultaneous CCT and TCD examinations demonstrated that coincident and statistically significant (p < 0.01) increase of actual CCT (6.7 msec) was found only in the severe grade of vasospasm (BFV 200 cm/s). The authors discuss the role of CCT and TCD monitoring in the management of aneurysmal subarachnoid hemorrhage.

Correlation of Transcranial Color Doppler to N20 Somatosensory Evoked Potential Detects Ischemic Penumbra in Subarachnoid Hemorrhage

“…12 ). A previous study investigated correlation between SSEP Central Conduction Time (CCT) and vasospasm and found a statistically significant (p < 0.01) increase in actual CCT (6.7 msec) in only the severe grade of vasospasm (blood flow velocity >200 cm/s) in subarachnoid hemorrhage [24]. By contrast, in our approach, variations of 1/vMCA and N20 cortical amplitude showed correlation before damage developed and independently from vasospasm.…”

Prognostic significance of SSEP, BAEP and serum S-100B monitoring after aneurysm surgery

“…Following aneurysmal subarachnoid hemorrhage (SAH), there is a serious risk of delayed cerebral ischemia. Clinical signs of late ischemic deterioration develop in 20-25% of the cases, and mortality rate is about 10% (2).…”

“…Boxplots showing EP scores(1)(2)(3)(4) in five outcome groups (GOS) after aneurysm surgery. ( median; 75%, 25%, 100%, 0%; n, number of patients).…”

“…Change of evoked potential (EP) grades(1)(2)(3)(4) in numbers from admission (left column) to discharge (upper row). Italic numbers are used for unchanged EPs.…”