title: The role of oculopneumoplethysmography in detecting acute carotid artery thrombosis in patients with neurologic deficits after carotid endarterectomy.
abstract: 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.
  
  
  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.
authors.affiliation: Vascular Section and Vascular Laboratory, Charleston, West Virginia, USA.
authors.forename: A F
authors.initials: AF
authors.lastname: AbuRahma
authors.forename: M A
authors.initials: MA
authors.lastname: Choueiri
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D002341:Carotid Artery Thrombosis / Q000175:diagnosis*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009880:Ophthalmic Artery / Q000502:physiology*; D010991:Plethysmography / Q000706:statistics & numerical data; D011183:Postoperative Complications / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D013997:Time Factors; D014463:Ultrasonography