Ocular Subclinical Changes by High-grade Carotid Stenosis

Overview

58 patients (40 men, 18 women) affected by high-grade carotid stenosis wereexamined using automated perimetry and electroretinography. Patients’ agesranged from 53 to 83 years with a mean of 67 years.We examined 29 patients withunilateral and 29 patients with bilateral symptomatic stenosis of carotid arteriesand cerebrovascular alterations, withouth ocular changes.Visual field defects were found by 41 patients (70.6 %), by 51.3 % patients therewere mild or middle defects, by 48.7 % hard defects. The results using electroretinographyshowed significant amplitude decrease and prolonged latencies of theoscillatory potentials on ipsilateral side in unilateral cases. Significant decreaseof amplitudes OP2 in patients after the attack of amaurosis fugax has beenobserved too. The critical value of this amplitude was estimated to 37
V.High-grade stenosis of carotid arteries are accompanied by visual field defectsand electric retinal functions disorders at the time when objective finding on thefundus is normal. The cause of these disorders might be decreased arterialperfusion or microembolization.The perimetry and ERG findings didn’t corelate, nevertheless both tests can beuseful for detection of early retinal alterations and represent a help-method todetermine indications for carotid endarterectomy.

Key words:
high-grade carotid stenosis,computer perimetry, electroretinography,amaurosis fugax