Abstract
Purpose: :
To explore the potential of OCT in the detection and monitoring of treatment of cystoid macular edema (CME) in patients with retinitis pigmentosa (RP).
Methods: :
Prospective clinical study in 50 patients diagnosed having RP. Diagnosis was established using funduscopy, visual field testing, Ganzfeld–ERG (ISCEV protocol) and dark–adaptometry. All patients underwent OCT and BCVA–testing (Snellen and ETDRS). If CME was present, 1st, 2nd and 3rd line of treatment were: acetazolamide orally, parabulbar or intravitreal steroids (triamcinolone), respectively. Follow–up exams with OCT and VA measurements were scheduled 2, 4, 6, 12, 24 and 36 weeks after initiation of therapy. Outcome measures were visual acuity (VA) and reduction of retinal thickness measured in OCT images. Statistical significance was defined p<0.05.
Results: :
Out of 50 patients diagnosed with RP, 13 showed CME in OCT scans (26%). Only 6 patients were diagnosed having CME in routine clinical examination (12%). Eight patients were treated with acetazolamide, 2 were eventually treated with triamcinolone, since no effect of acetazolamide was found after 4 weeks. 5 patients were only monitored but not treated (refusal of treatment, azetazolamide intolerance). A statistically significant increase in BCVA (average of 9.8 letters) was observed 12 weeks after initiation of therapy in all treated patients. Simultaneous significant reduction in retinal thickness of 28.9±13µm was measured in OCT images. No rebound effect was observed after cessation of therapy up to 9 months after initiation of therapy in patients treated with azetazolamide only. The 2 patients treated with triamcinolone showed a rebound effect after 7 and 8 months and required repeated injections. None of the untreated patients showed improvement in BCVA or reduction of retinal thickness. No severe side–effects were observed.
Conclusions: :
OCT has a higher sensitivity to detect CME than routine clinical examination in RP. Acetazolamide treatment improved vision and reduced retinal thickness in most patients with CME. Triamcinolone was effective in patients not responding to acetazolamide. OCT was an excellent tool for diagnosis and monitoring of treatment effects in CME in RP–patients.
Keywords: macula/fovea • retinal degenerations: hereditary • clinical (human) or epidemiologic studies: outcomes/complications