Biomedical subjects

T S Padayachee

Publications and source records attributed to T S Padayachee.

39 records · Page 3Linked to original sources

PubMedDate not supplied

Ultrasound screening for internal carotid disease-II. Sensitivity and specificity of a single site periorbital artery test.

Supraorbital artery blood flow was examined non-invasively with continuous wave Doppler-shifted ultrasound and spectral analysis. The results were used to assess the ipsilateral internal carotid artery in 155 patients undergoing carotid angiography. The ultrasound parameters used were the temporal artery occlusion test and A/B ratios of both resting and augmented supraorbital sonagrams. A retrospective study showed this combination to have a sensitivity of 65% for internal carotid disease which did not encroach on the lumen and for all other angiographically demonstrated lesions an average sensitivity of 94% and specificity of 92%. Augmented supraorbital pulses were more sensitive for detection of carotid artery disease than resting supraorbital pulses. Of the 61 lesions in which both resting and augmented supraorbital A/B ratios were obtained, the augmented supraorbital pulse detected 48 (79%) whilst the resting supraorbital pulse detected 29 (48%). Localised carotid bruits were poor indicators of carotid artery disease, having a sensitivity of only 27%.

Angiography↗

PubMedDate not supplied

Doppler ultrasound assessment of the internal carotid artery following carotid endarterectomy.

Doppler-shifted ultrasound with spectral analysis was used to assess the internal carotid arteries of 48 patients who had undergone carotid endarterectomy (58 carotid endarterectomies). Three patients died in the immediate post-operative period, therefore 45 patients, who represented 54 endarterectomies, were assessed for up to six years following surgery (mean--thirty-four months). Ultrasound tests demonstrated total occlusion of the internal carotid artery in 7 patients within the first post-operative week. Sonograms from the supraorbital and common carotid arteries exhibit two peaks during cardiac systole (A and B). The post-operative A/B ratios were abnormal in 24 instances and these were associated with symptoms in seven. Of these 24, 7 developed severe disease in the internal carotid artery during the six year follow-up period; five were associated with symptoms. Post-operative A/B ratios were normal in 23 instances, 19 of which remained normal at follow-up. None of these nineteen developed symptoms. Only patients with abnormal post-operative A/B ratios subsequently developed severe occlusive disease in the internal carotid artery during the follow-up assessment. Thirty-eight patients underwent unilateral carotid endarterectomy, eight of whom had severe internal carotid artery disease at the contralateral bifurcation at the time of carotid endarterectomy. A further four patients developed severe occlusive disease in the contralateral internal carotid artery during the follow-up period, one of whom was symptomatic.

Adult↗

PubMedDate not supplied

Monitoring cerebral perfusion during carotid endarterectomy.

Transcranial pulsed Doppler ultrasound was used to monitor blood velocity in the middle cerebral artery (MCA) of two patients during ipsilateral carotid endarterectomy. In the first patient the ultrasound data demonstrated a non-functioning shunt which was corrected by repositioning the distal end of the shunt. In the second patient MCA blood velocity data demonstrated that clamping of the external carotid artery would have resulted in complete cessation of MCA flow throughout endarterectomy. These cases illustrate the benefit that this technique offers to the individual patient undergoing carotid surgery.

Aged↗