Vitrectomy for diabetic eye disease. The prognostic value of pre-operative electroretinography and visual evoked cortical potentials.
An investigation was carried out into the prognostic value of standard flash electroretinography (ERG) and visual-evoked cortical potentials (VECP) recorded for 87 diabetic eyes prior to vitrectomy. 95% of the eyes with a recordable ERG b-wave achieved a post-operative visual acuity (VA) of 0.05 or better (positive predictive value), but only 35% of the eyes with a good post-operative VA had a recordable b-wave (sensitivity). The corresponding values for the ERG a-wave were 67 and 72%, and for the VECP 77 and 69%, respectively. A non-recordable b-wave in the ERG was associated with a poor visual outcome (VA less than 0.05) in 45% of cases (negative predictive value), and 97% of the eyes with a poor visual outcome had a nonrecordable b-wave (specificity). The corresponding values for the ERG a-wave were 42 and 37%, and for the VECP 53 and 63%, respectively. Consequently, the odds ratio for an unfavourable visual outcome (VA less than 0.05) was greater for a non-recordable b-wave (15.7) than for a nonrecordable VECP (3.8) or a non-recordable a-wave (1.5). Recordability of the b-wave gave the best prediction for attached macula. Extensive photocoagulation diminished all ERG and VECP amplitudes. Vitreous opacities had no significant effect on the ERG or VECP.
Summanen
P
P
Department of Ophthalmology, Helsinki University Central Hospital, Finland.
D000293:Adolescent; D000328:Adult; D000368:Aged; D003627:Data Interpretation, Statistical; D003930:Diabetic Retinopathy / Q000150:complications / Q000601:surgery*; D003972:Diathermy; D004596:Electroretinography; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D008028:Light Coagulation; D008266:Macula Lutea / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care; D011379:Prognosis; D012016:Reference Values; D012160:Retina / Q000503:physiopathology; D012163:Retinal Detachment / Q000209:etiology / Q000503:physiopathology / Q000601:surgery; D014792:Visual Acuity; D014821:Vitrectomy; D014823:Vitreous Hemorrhage / Q000209:etiology / Q000503:physiopathology / Q000601:surgery