Normal central retinal function and structure preserved in retinitis pigmentosa.
OBJECTIVE
To determine whether normal function and structure, as recently found in forms of Usher syndrome, also occur in a population of patients with nonsyndromic retinitis pigmentosa (RP).


METHODS
Patients with simplex, multiplex, or autosomal recessive RP (n = 238; ages 9-82 years) were studied with static chromatic perimetry. A subset was evaluated with optical coherence tomography (OCT). Co-localized visual sensitivity and photoreceptor nuclear layer thickness were measured across the central retina to establish the relationship of function and structure. Comparisons were made to patients with Usher syndrome (n = 83, ages 10-69 years).


RESULTS
Cross-sectional psychophysical data identified patients with RP who had normal rod- and cone-mediated function in the central retina. There were two other patterns with greater dysfunction, and longitudinal data confirmed that progression can occur from normal rod and cone function to cone-only central islands. The retinal extent of normal laminar architecture by OCT corresponded to the extent of normal visual function in patients with RP. Central retinal preservation of normal function and structure did not show a relationship with age or retained peripheral function. Usher syndrome results were like those in nonsyndromic RP.


CONCLUSIONS
Regional disease variation is a well-known finding in RP. Unexpected was the observation that patients with presumed recessive RP can have regions with functionally and structurally normal retina. Such patients will require special consideration in future clinical trials of either focal or systemic treatment. Whether there is a common molecular mechanism shared by forms of RP with normal regions of retina warrants further study.
Jacobson
Samuel G
SG
Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. jacobsos@mail.med.upenn.edu
Roman
Alejandro J
AJ
Aleman
Tomas S
TS
Sumaroka
Alexander
A
Herrera
Waldo
W
Windsor
Elizabeth A M
EA
Atkinson
Lori A
LA
Schwartz
Sharon B
SB
Steinberg
Janet D
JD
Cideciyan
Artur V
AV
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D055253:Color Vision / Q000502:physiology; D015350:Contrast Sensitivity / Q000502:physiology*; D003623:Dark Adaptation / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020419:Photoreceptor Cells, Vertebrate / Q000473:pathology / Q000502:physiology*; D012174:Retinitis Pigmentosa / Q000175:diagnosis / Q000503:physiopathology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D052245:Usher Syndromes / Q000175:diagnosis / Q000503:physiopathology; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology*