Abstract
Abstract: :
Purpose: The differentiation between an acquired and congenital (long standing) occipital lobe infarct may be made by the presence of retinal nerve fibre layer loss in the latter.Clinical examination and red–free photography may not allow adequate assessment of the nerve fibre layer especially in eyes with diffuse thinning. Newly avaliable imaging devices may aid the ophthalmologist in assessment of the retinal nerve fibre layer in this condition Methods: Prospective observational case series of patients referred to the neuro–ophthalmological service with occipital infarction confirmed on MRI. All patients were asymptomatic of the field loss and had normal cardiovascular and neurological examinations. All patients had a otherwise normal ocular examination. Automated visual fields were performed on all the patient as well as dilated fundal photography of the disc and retinal nerve fibre analysis using the OCT 3. Results: Three patients (2 males, 1 female) were reviewed during the 4 months of the study.Mean age 36 (range 27 – 45).Visual field examination showed complete right homonymous hemianopic defects in two patient and a bilateral homonymous scotomatas defect in one patient. MRI scans showed left occipital infarction in 2 patients and bilateral infarction in one patient. Optic disc examination clinially showed was unremakable in 2 patients and in one patient showed band atrophy in the right eye. OCT identified a pattern of band atrophy in 2 patients in the eyes with the temporal hemianopia and diffuse thinning of the superior and inferior nerve fibres in the ipsilateral eyes of the same patients. In the third patient there was evidence of inferior field loss in both eyes. Conclusions: The OCT identified patterns of nerve fibre layer as expected anatomically but not visualized clinically. The quantitiative data obtained provides useful basline information for these patients. OCT was especially useful in the identification of diffuse thinning of the nerve fibre layer in the eyes with nasal hemianopia.
Keywords: neuro-ophthalmology: diagnosis • nerve fiber layer • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)