The role of the oculopneumoplethysmography in detecting postendarterectomy in carotid stenosis or thrombosis.

The oculopneumoplethysmography has been a well established tool in the diagnosis of significant carotid artery stenosis; however, very few articles have studied the role of the OPG/Gee in detecting the postendarterectomy stenosis or thrombosis. The purpose of this article is to study that role. Eighty-two patients who had carotid endarterectomy and postoperative OPG/Gee were reviewed and compared with carotid arteriograms. Sixteen of these had bilateral and 66 had unilateral carotid endarterectomy. Seventy-nine of these patients had angiograms and three were explored. The total arteries studied were 98. Thirteen of these oculopneumoplethysmograms were done in the recovery room and the rest a few days to three years later. A carotid stenosis of 50% or more in diameter was considered significant. There were 10 positive oculopneumoplethysmograms, nine of which were confirmed by angiograms; i.e., 10.0% false positive rate. There were also three positive oculopneumoplethysmograms which were explored in surgery and found to be thrombosed; i.e., a total of 13 positive oculopneumoplethysmograms, 12 of which were confirmed which made the real false positive rate 7.7%. Eleven patients had positive arteriograms, nine of which had positive oculopneumoplethysmograms; i.e., 81.8% diagnostic sensitivity (9/11). Eighty-four arteries were considered normal by arteriogram (11 of which had insignificant stenosis), 83 of these had negative oculopneumoplethysmograms; i.e., 98.8% diagnostic specificity (83/84). The false negative rate was 2.4% (2/85). The overall accuracy rate was 96.8% (92/95). If the three explored arteries were added, the overall accuracy rate would be 96.9% (95/98). To conclude, the OPG/Gee is a valuable tool in detecting immediate postendarterectomy thrombosis or recurrent stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)