TY - JOUR
T1 - Relationship between foveal cone specialization and pit morphology in Albinism
AU - Wilk, Melissa A.
AU - McAllister, John T.
AU - Cooper, Robert F.
AU - Dubis, Adam M.
AU - Patitucci, Teresa N.
AU - Summerfelt, Phyllis
AU - Anderson, Jennifer L.
AU - Stepien, Kimberly E.
AU - Costakos, Deborah M.
AU - Jr, Thomas B.Connor
AU - Wirostko, William J.
AU - Chiang, Pei Wen
AU - Dubra, Alfredo
AU - Curcio, Christine A.
AU - Brilliant, Murray H.
AU - Gail Summers, C.
AU - Carroll, Joseph
PY - 2014
Y1 - 2014
N2 - Purpose. Albinism is associated with disrupted foveal development, though intersubject variability is becoming appreciated. We sought to quantify this variability, and examine the relationship between foveal cone specialization and pit morphology in patients with a clinical diagnosis of albinism. Methods. We recruited 32 subjects with a clinical diagnosis of albinism. DNA was obtained from 25 subjects, and known albinism genes were analyzed for mutations. Relative inner and outer segment (IS and OS) lengthening (fovea-to-perifovea ratio) was determined from manually segmented spectral domain-optical coherence tomography (SD-OCT) B-scans. Foveal pit morphology was quantified for eight subjects from macular SD-OCT volumes. Ten subjects underwent imaging with adaptive optics scanning light ophthalmoscopy (AOSLO), and cone density was measured. Results. We found mutations in 22 of 25 subjects, including five novel mutations. All subjects lacked complete excavation of inner retinal layers at the fovea, though four subjects had foveal pits with normal diameter and/or volume. Peak cone density and OS lengthening were variable and overlapped with that observed in normal controls. A fifth hyper-reflective band was observed in the outer retina on SD-OCT in the majority of the subjects with albinism. Conclusions. Foveal cone specialization and pit morphology vary greatly in albinism. Normal cone packing was observed in the absence of a foveal pit, suggesting a pit is not required for packing to occur. The degree to which retinal anatomy correlates with genotype or visual function remains unclear, and future examination of larger patient groups will provide important insight on this issue.
AB - Purpose. Albinism is associated with disrupted foveal development, though intersubject variability is becoming appreciated. We sought to quantify this variability, and examine the relationship between foveal cone specialization and pit morphology in patients with a clinical diagnosis of albinism. Methods. We recruited 32 subjects with a clinical diagnosis of albinism. DNA was obtained from 25 subjects, and known albinism genes were analyzed for mutations. Relative inner and outer segment (IS and OS) lengthening (fovea-to-perifovea ratio) was determined from manually segmented spectral domain-optical coherence tomography (SD-OCT) B-scans. Foveal pit morphology was quantified for eight subjects from macular SD-OCT volumes. Ten subjects underwent imaging with adaptive optics scanning light ophthalmoscopy (AOSLO), and cone density was measured. Results. We found mutations in 22 of 25 subjects, including five novel mutations. All subjects lacked complete excavation of inner retinal layers at the fovea, though four subjects had foveal pits with normal diameter and/or volume. Peak cone density and OS lengthening were variable and overlapped with that observed in normal controls. A fifth hyper-reflective band was observed in the outer retina on SD-OCT in the majority of the subjects with albinism. Conclusions. Foveal cone specialization and pit morphology vary greatly in albinism. Normal cone packing was observed in the absence of a foveal pit, suggesting a pit is not required for packing to occur. The degree to which retinal anatomy correlates with genotype or visual function remains unclear, and future examination of larger patient groups will provide important insight on this issue.
KW - Adaptive optics
KW - Albinism
KW - Foveal development
KW - Foveal morphology
UR - http://www.scopus.com/inward/record.url?scp=84904346942&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84904346942&partnerID=8YFLogxK
U2 - 10.1167/iovs.13-13217
DO - 10.1167/iovs.13-13217
M3 - Article
C2 - 24845642
AN - SCOPUS:84904346942
SN - 0146-0404
VL - 55
SP - 4186
EP - 4198
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 7
ER -