A new, more dependable methodology for the use of transcranial Doppler ultrasonography in the management of subarachnoid haemorrhage

Abstract

The role of transcranial Doppler ultrasound (TCD) in clinical decision making about vasospasm due to subarachnoid haemorrhage (SAH), shows a great variation according to neurosurgical clinics. In this prospective study, a total of 143 patients, admitted to Marmara University Department of Neurosurgery between January 1991 to March 1995 and treated surgically with the diagnosis of aneurysmal SAH, were examined by TCD. Eighty of these patients fulfilled the requirements for inclusion. In order to increase clinical dependability of TCD, a new grading system is proposed and tested in comparison with the one previously used, which takes absolute flow velocities as the main parameter in grading. The new, individually based TCD grading system is proposed to minimize the pitfalls caused by proximal stenosis, wide range of normal Vm values and proximally evolving vasospasm. We concluded that: 1) The new, individually based TCD grading system has a high degree of clinical dependability. 2) Daily TCD examinations supply reliable predictive information about developing delayed ischaemic deficit (DID). If a TCD Gr II patient shows an increase of 35 cm/sec (in 24 hours) in Vm value, his probability of developing DID was found to be 60% (p < 0.05); if a TCD Gr B III patient shows the same rate of increase in Vm, his probability of developing DID was 80% (< 0.05). 3) TCD has an important clinical role in decision making about the management of SAH patients. 4) Surgical manipulation causes a reversible increase of one or two TCD-grades in the early postoperative days.

Cerebral hemodynamic impairment after aneurysmal subarachnoid hemorrhage as evaluated using transcranial Doppler ultrasonography: relationship to delayed cerebral ischemia and clinical outcome

“…We found that the detection of HDI was clearly associated with the development of delayed cerebral ischemia after SAH, but no ischemic complications followed the registration of vasospasm without HDI. Although a positive correlation between arterial vasospasm and the development of delayed ischemia has been confirmed in a number of studies, 12,15,16,18,24,38 several authors have reported on patients who tolerated severe angiographically confirmed vasospasm, 12 as well as extreme increases in BFV values, 5,6,29 with no neurological deterioration. At the same time, a number of injurious complications besides vasospasm have been associated with DCI and poor clinical outcome after SAH.…”

Grading and hemodynamic follow-up study of arteriovenous malformations with transcranial Doppler ultrasonography.

“…Surgical manipulation, which was postulated to be the cause of the reversible increase in V m due to increased vasospasm in the TCD follow-up study of aneurysmal subarachnoid hemorrhage, might explain the delay in normalization of V m . 24 PI, which is a mathematical ratio, seems to be less affected by immediate postoperative reversible vasospasm. Therefore, one can conclude that PI is a more dependable parameter to evaluate the physiological success of the operation in early postoperative days.…”

Role of Transcranial Doppler in the Evaluation of Vasculopathy in Tuberculous Meningitis

“…The pulsatility index (PI) was obtained for each intracranial artery as (Peak systolic velocity-end diastolic velocity)/mean flow velocity. [ 4 , 5 , 10 , 11 ] A value of 0.6–1.1 represented the normal range for the PI in the intracranial arteries. [ 4 , 5 , 10 , 11 , 12 ]…”