TY - JOUR
T1 - Comparing Retinal Structure in Patients with Achromatopsia and Blue Cone Monochromacy Using OCT
AU - Patterson, Emily J.
AU - Langlo, Christopher S.
AU - Georgiou, Michalis
AU - Kalitzeos, Angelos
AU - Pennesi, Mark E.
AU - Neitz, Jay
AU - Hardcastle, Alison J.
AU - Neitz, Maureen
AU - Michaelides, Michel
AU - Carroll, Joseph
N1 - Publisher Copyright:
© 2021 American Academy of Ophthalmology
PY - 2021/9
Y1 - 2021/9
N2 - Purpose: To compare foveal hypoplasia and the appearance of the ellipsoid zone (EZ) at the fovea in patients with genetically confirmed achromatopsia (ACHM) and blue cone monochromacy (BCM). Design: Retrospective, multicenter observational study. Participants: Molecularly confirmed patients with ACHM (n = 89) and BCM (n = 33). Methods: We analyzed high-resolution spectral-domain OCT (SD-OCT) images of the macula from patients with BCM. Three observers independently graded SD-OCT images for foveal hypoplasia (i.e., retention of ≥1 inner retinal layers at the fovea), and 4 observers judged the integrity of the EZ at the fovea, based on an established grading scheme. These measures were compared with previously published data from the patients with ACHM. Main Outcome Measures: Presence of foveal hypoplasia and EZ grade. Results: Foveal hypoplasia was significantly more prevalent in ACHM than in BCM (P < 0.001). In addition, we observed a significant difference in the distribution of EZ grades between ACHM and BCM, with grade II EZ being by far the most common phenotype in BCM (61% of patients). In contrast, patients with ACHM had a relatively equal prevalence of EZ grades I, II, and IV. Grade IV EZ was 2.6 times more prevalent in ACHM compared with BCM, whereas grade V EZ (macular atrophy) was present in 3% of both the ACHM and BCM cohorts. Conclusions: The higher incidence of foveal hypoplasia in ACHM than BCM supports a role for cone activity in foveal development. Although there are differences in EZ grades between these conditions, the degree of overlap suggests EZ grade is not sufficient for definitive diagnosis, in contrast to previous reports. Analysis of additional OCT features in similar cohorts may reveal differences with greater diagnostic value. Finally, the extent to which foveal hypoplasia or EZ grade is prognostic for therapeutic potential in either group remains to be seen, but motivates further study.
AB - Purpose: To compare foveal hypoplasia and the appearance of the ellipsoid zone (EZ) at the fovea in patients with genetically confirmed achromatopsia (ACHM) and blue cone monochromacy (BCM). Design: Retrospective, multicenter observational study. Participants: Molecularly confirmed patients with ACHM (n = 89) and BCM (n = 33). Methods: We analyzed high-resolution spectral-domain OCT (SD-OCT) images of the macula from patients with BCM. Three observers independently graded SD-OCT images for foveal hypoplasia (i.e., retention of ≥1 inner retinal layers at the fovea), and 4 observers judged the integrity of the EZ at the fovea, based on an established grading scheme. These measures were compared with previously published data from the patients with ACHM. Main Outcome Measures: Presence of foveal hypoplasia and EZ grade. Results: Foveal hypoplasia was significantly more prevalent in ACHM than in BCM (P < 0.001). In addition, we observed a significant difference in the distribution of EZ grades between ACHM and BCM, with grade II EZ being by far the most common phenotype in BCM (61% of patients). In contrast, patients with ACHM had a relatively equal prevalence of EZ grades I, II, and IV. Grade IV EZ was 2.6 times more prevalent in ACHM compared with BCM, whereas grade V EZ (macular atrophy) was present in 3% of both the ACHM and BCM cohorts. Conclusions: The higher incidence of foveal hypoplasia in ACHM than BCM supports a role for cone activity in foveal development. Although there are differences in EZ grades between these conditions, the degree of overlap suggests EZ grade is not sufficient for definitive diagnosis, in contrast to previous reports. Analysis of additional OCT features in similar cohorts may reveal differences with greater diagnostic value. Finally, the extent to which foveal hypoplasia or EZ grade is prognostic for therapeutic potential in either group remains to be seen, but motivates further study.
KW - Achromatopsia
KW - Blue cone monochromacy
KW - Cone
KW - Ellipsoid zone
KW - Fovea
KW - Foveal hypoplasia
KW - Hyper-reflective band
KW - Imaging
KW - OCT
KW - Photoreceptor
KW - SD-OCT
KW - X-linked cone dysfunction
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U2 - 10.1016/j.xops.2021.100047
DO - 10.1016/j.xops.2021.100047
M3 - Article
AN - SCOPUS:85121266757
SN - 2666-9145
VL - 1
JO - Ophthalmology Science
JF - Ophthalmology Science
IS - 3
M1 - 100047
ER -