Prognostic factors in vitreous surgery for proliferative diabetic retinopathy.
A total of 25 proliferative diabetic eyes of 24 patients scheduled for vitrectomy were examined. The overall preoperative visual acuity was below 0.1, corresponding to hand movement in most patients because of intravitreal hemorrhage. Hence, funduscopy was not possible. The following tests were performed in addition to standard clinical examination: Purkinje entoptic phenomenon, laser interferometry, perception of color flashes, and flicker-VEP using 1.8, 7.6, 15, and 30 Hz as stimulating frequencies. Only the flicker-VEP revealed results predicting reliably the functional visual outcome at 6 months after vitrectomy. Patients with a positive preoperative response to 15 or 30 Hz had a significantly (P < 0.05) better visual outcome at 6 months after vitrectomy (mean postoperative visual acuity 0.11; 95% confidence interval, 1/25-0.32) as compared with patients showing a positive preoperative VEP-response to only 1.8 and 7.6 Hz (mean postoperative visual acuity, hand movement; 95% confidence interval, light without projection--1/35). The flicker-VEP can give additional information about the integrity of the retina and the function of the optic nerve and can therefore help the surgeon to predict the functional result after vitrectomy.
Department of Ophthalmology, University of Würzburg, Germany.
C L
CL
Schönfeld
T
T
Schneider
U
U
Körner
H P
HP
Heidenkummer
A
A
Kampik
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003119:Color Perception Tests; D003930:Diabetic Retinopathy / Q000503:physiopathology / Q000601:surgery*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D007368:Interferometry; D008027:Light; D008297:Male; D008875:Middle Aged; D009900:Optic Nerve / Q000502:physiology; D011379:Prognosis; D012160:Retina / Q000502:physiology; D012680:Sensitivity and Specificity; D014792:Visual Acuity / Q000502:physiology; D014821:Vitrectomy