The IS/OS junction layer in the natural history of type 2 idiopathic macular telangiectasia.
2012 Nov 29
Journal Article
Authors:
Sallo, F.B.;
Peto, T.;
Egan, C.;
Wolf-Schnurrbusch, U.E.K.;
Clemons, T.E.;
Gillies, M.C.;
Pauleikhoff, D.;
Rubin, G.S.;
Chew, E.Y.;
Bird, A.C.
Secondary:
Invest Ophthalmol Vis Sci
Volume:
53
Pagination:
7889-95
Issue:
12
PMID:
23092925
Keywords:
Aged; Female; Follow-Up Studies; Humans; Male; Middle Aged; Retinal Photoreceptor Cell Inner Segment; Retinal Photoreceptor Cell Outer Segment; Retinal Telangiectasis; Sensory Thresholds; Time Factors; Tomography, Optical Coherence; visual acuity
Abstract:
PURPOSE: To document the progression of a break in the photoreceptor inner segment/outer segment (IS/OS) junction layer and its functional correlates over time in the natural history of type 2 idiopathic macular telangiectasia (type 2 MacTel).METHODS: Patients with at least 1 year of follow-up were selected from the MacTel Study. En face images were created by manual segmentation of the IS/OS junctional line in volume scans acquired using a spatial-domain optical coherence tomography retinal imaging unit. Retinal sensitivity thresholds were determined using a retinal microperimeter unit. Aggregate retinal sensitivity loss within IS/OS lesions was calculated. Changes over time in an area of IS/OS defects and retinal sensitivity were analyzed.RESULTS: thirty-nine eyes of 23 patients (mean age: 62.3 ± 9.2 years) were analyzed. Mean follow-up time was 1.9 years (range: 1-3 years). Mean IS/OS break area at baseline was 0.575 mm(2) (SE = 0.092, 95% confidence interval [CI]: 0.394-0.756 mm(2)). The cluster-adjusted mean annual progression rate in IS/OS break area was 0.140 mm(2) (SE = 0.040, 95% CI: 0.062-0.218 mm(2), P < 0.001). Mean aggregate retinal sensitivity loss was at baseline 28.56 dB (SE = 5.43, 95% CI: 17.32-39.80 dB, n = 28), a positive correlation with IS/OS lesion area was present (P < 0.001). The mean annual rate of change in aggregate sensitivity loss was 5.14 dB (SE = 1.51, 95% CI: 2.19-8.10 dB, P < 0.001, n = 37), a significant correlation with lesion area increase was found (P = 0.006).CONCLUSIONS: Both IS/OS break area and rate of enlargement correlate with aggregate retinal sensitivity loss in type 2 MacTel. En face OCT imaging of the IS/OS layer provides a functionally relevant method for documenting disease progression in type 2 MacTel.
