Peripapillary retinal nerve fiber layer thinning in patients with autosomal recessive cone-rod dystrophy.
OBJECTIVE
To evaluate peripapillary retinal nerve fiber layer (RNFL) thickness using spectral-domain optical coherence tomography in patients with autosomal recessive cone-rod dystrophy (CRD).


METHODS
Cross-sectional study.


METHODS
Eleven patients (22 eyes) with CRD were studied, including 4 patients with identified ABCA4 gene mutations. Peripapillary RNFL thickness was measured in 16 segments from 4 quadrants. The analyses were based on age and disc size-adjusted normative data. An abnormal thinning was considered when RNFL thickness measurements were less than the fifth percentile in at least 2 of 4 segments in a quadrant. Mean RNFL thickness was compared quantitatively with normative data obtained from 134 subjects.


RESULTS
Eight patients (73%) had peripapillary RNFL thinning in at least 1 quadrant of at least 1 eye, including 3 of 4 patients with known ABCA4 gene mutations. Peripapillary RNFL thinning in the temporal quadrant was seen most commonly in 11 (79%) of 14 eyes with thinning in at least 1 quadrant. Significant thinning of the overall peripapillary RNFL was observed in CRD patients compared with controls (P = .0002). Subgroup analysis showed that 8 (89%) of 9 patients who were older than 40 years had thinning in at least 1 quadrant of at least 1 eye.


CONCLUSIONS
Peripapillary RNFL thinning was observed commonly in our patients with autosomal recessive CRD. The results confirm that the inner retinal structures can be affected in outer retinal disease. Careful evaluation of the inner retina may be important in determining the success rate of potential treatments for predominantly outer retinal diseases.
Pasadhika
Sirichai
S
Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA.
Fishman
Gerald A
GA
Allikmets
Rando
R
Stone
Edwin M
EM
D018528:ATP-Binding Cassette Transporters / Q000235:genetics; D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D005808:Genes, Recessive; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology*; D020419:Photoreceptor Cells, Vertebrate / Q000473:pathology*; D012162:Retinal Degeneration / Q000175:diagnosis* / Q000235:genetics*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence
C056475:ABCA4 protein, human; D018528:ATP-Binding Cassette Transporters