Carotid compression test and supraorbital photoelectric plethysmography in patients with carotid TIAs.

Fifty-two patients with carotid transient ischemic attacks (TIAs) were subjected to subsequent compression of the common carotid and superficial temporal artery. An EEG recording was monitored simultaneously with plethysmograms from both supraorbital regions during the arterial compression period. All patients were angiographically classified as normal (Group A, n = 25) with less than 50% stenosis (Group B, n = 14) and with more than 50% stenosis (Group C, n = 13), according to the degree of internal carotid stenosis. The carotid compression test was positive in 6 (11%) of our 52 patients, corresponding to 1 (4%) patient from Group A, 1 (7%) from Group B and 4 (30%) from Group C. In contrast, supraorbital photoelectric plethysmography (SOPPL) yielded abnormal results in 17 (33%) of our 52 patients, corresponding to 3 (12%) patients from Group A, 4 (28%) from Group B and 10 (77%) from Group C. We conclude that in view of the false positive results (12%) obtained with the SOPPL technique, the clinician who interprets these findings should be careful and combine these tests with other tests, preferably hemodynamic, for a final decision about the patient's status.