Macular atrophy in birdshot retinochoroidopathy: an optical coherence tomography and multifocal electroretinography analysis.
OBJECTIVE
The purpose of this study was to evaluate macular atrophy by frequency-domain optical coherence tomography (OCT) in patients with birdshot retinochoroidopathy and to compare the resulting thickness measures with visual acuity and multifocal electroretinography (mfERG).


METHODS
Measures were obtained from 14 eyes of 7 patients with birdshot retinochoroidopathy and 23 normal eyes. Optical coherence tomography-3 measures of macular thinning were related to visual acuity, mfERG response density, and time since diagnosis. Horizontal midline frequency-domain OCT scans identified which layers of the retina were primarily responsible for macular thinning.


RESULTS
All eyes with a history of birdshot retinochoroidopathy for >10 years had abnormal mfERG response densities. Compared with those without anatomic thinning (n = 8), eyes with anatomic thinning (n = 6) had significantly lower visual acuity (P = 0.0006), foveal response density (P = 0.006), and overall mfERG response density (P = 0.009). Segmentation of retinal layers on frequency-domain OCT scans showed that anatomic thinning was as a result of reduction in the receptor 1 layer (REC+), the thickness of the segment extending from the proximal border of the outer plexiform layer to the Bruch membrane-choroid interface.


CONCLUSIONS
Macular atrophy, as reflected in OCT evidence of macular thinning and mfERG evidence of macular function, occurs in patients with long-standing birdshot retinochoroidopathy. Measures of retinal layer thicknesses by frequency-domain OCT suggest that the atrophy occurs primarily in the outer retina.
Birch
David G
DG
The Retina Foundation of the Southwest, Dallas, Texas 75231, USA. dbirch@retinafoundation.org
Williams
Patrick D
PD
Callanan
David
D
Wang
Robert
R
Locke
Kirsten G
KG
Hood
Donald C
DC
D000368:Aged; D000369:Aged, 80 and over; D001284:Atrophy; D002829:Choroid / Q000473:pathology; D015862:Choroid Diseases / Q000503:physiopathology*; D004596:Electroretinography; D005260:Female; D006801:Humans; D008266:Macula Lutea / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D020419:Photoreceptor Cells, Vertebrate / Q000473:pathology; D012164:Retinal Diseases / Q000503:physiopathology*; D055213:Retinal Pigment Epithelium / Q000473:pathology; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology