Use of oculopneumoplethysmography (OPG-Gee) following carotid endarterectomy

The role of oculopneumoplethysmography in detecting acute carotid artery thrombosis in patients with neurologic deficits after carotid endarterectomy

BACKGROUND

This study analyzes the role of oculopneumoplethysmography (OPG/Gee) in detecting acute carotid thrombosis (CAT) after carotid endarterectomy (CEA) in a timely fashion for immediate exploration, and minimizing unnecessary surgery.

PATIENTS AND METHODS

Fifty-three patients with neurologic deficits that were noticed after CEA in the operating or recovery room had immediate OPG/Gee. Patients with a positive OPG underwent immediate exploration. Patients with a negative OPG had a duplex ultrasound (DU), and if positive for >/=50% stenosis, the patient underwent exploration. If the DU was negative, the patient underwent cerebral computed tomography scanning and angiography.

RESULTS

Thirty-one of 53 (58%) had a positive OPG, 30 (97%) of whom had CAT on exploration. Twenty-two of 53 (42%) with a negative OPG had a DU, 4 of whom had >/=50% stenosis (1 thrombosis) that was confirmed by exploration. The remaining 18 patients had a negative DU that was confirmed by angiography. OPG had an overall accuracy of 96% in detecting acute CAT, with a sensitivity of 97%, specificity of 95%, positive predictive value (PPV) of 97%, and a negative predictive value (NPV) of 95%. Combined OPG and selective DU had an overall accuracy of 98% in detecting surgically correctable lesions, with 100% sensitivity, 95% specificity 97% PPV, and 100% NPV. Mandatory exploration in all 53 patients would have resulted in 19 (36%) unnecessary surgeries versus 1 of 53 (2%) if exploration had been done based on OPG with selective DU (P <0.05). Even if exploration was done based only on the OPG, 30 of 34 surgical lesions would have been explored within a few minutes; only 4 would have been delayed until a DU was performed.

CONCLUSIONS

OPG/Gee is very sensitive and timely in detecting acute CAT, and carotid exploration in these patients can improve the results of CEA. It also minimizes unnecessary explorations. Patients with a negative OPG should undergo DU, and if positive, they should undergo exploration.

Completion angiography, is it really necessary?

BACKGROUND

Routine completion imaging after carotid endarterectomy (CEA) has been advocated by many investigators to detect and repair unsuspected defects with the goal of reducing perioperative morbidity and residual disease. However, completion imaging has been performed rarely in our practice. Our carotid registry was interrogated to determine whether omitting routine completion imaging adversely affected outcome.

METHODS

A retrospective review of 229 consecutive CEAs performed by one vascular surgeon during 1988 to 1996 was completed. Duplex follow-up was used to identify persistent residual defects, which were classified as 50% to 74%, 75% to 99%, and occlusion in the common (CCA), internal (ICA), and external (ECA) arteries and was available in 192 cases.

RESULTS

During the study period, eight completion angiograms were performed (3.5%) and 5 arteries were reopened. Combined stroke and death rate was 3.1% (7 of 229). Duplex follow-up, available on 192 patients, showed residual lesions in 29 patients (15%), but only 7 (3.6%) involving the internal or common carotid.

CONCLUSION

Routine completion imaging is not required to achieve acceptable morbidity and mortality and minimize residual problems after CEA. Attention to operative details with selective imaging will give excellent results.