Abstract
Purpose :
Choroidal assessment is critical for a myriad of ophthalmologic conditions. However, we lack studies which describe choroidal thickness among Hispanics. Hence, we performed a cross-sectional study among healthy volunteers to propose an estimate of mean choroidal thickness for this race/ethnicity, specifically those from Latin America.
Methods :
So far, we have recruited 50 volunteers from an outpatient clinic in Mexico City. We evaluated individuals from 20 to 30 years of age, clinically healthy, with a noncontributing history of systemic or ophthalmologic diseases, unremarkable funduscopic examination, and visual acuity of 20/20 (both eyes, no impairments and no refractive error more than 6DS). For each eligible case, we measured the choroidal thickness by EDI-OCT imaging per standard protocols [100 images, 5 x 30 mm, 765 x 496 pixels] per region. Eleven sections were taken starting from the subfoveal choroidal region (center) and onwards at 500-µm intervals to 3 mm nasal and 3 mm temporal (Figure). For our statistical approach, we began by estimating our precision as a function of sample size. We then described and plotted our results for 100 eyes (units of analysis) as shown in our Figure (Means and standard deviations for normally distributed data). Furthermore, we addressed if any significant differences existed between Hispanics and published results from other populations (non-Hispanic whites) by Student's t-test.
Results :
Given our sample, choroidal thickness measures are 14.9 µm around the population mean. Our results support that the choroids is thicker centrally and decreases towards the periphery. Also, those choroidal measurements among Hispanics are significantly thicker compared to non-Hispanic Whites. We did not note any statistically significant differences across genders (Males vs. females) or eye laterality (Right vs. left).
Conclusions :
Our pilot study builds towards proposing estimates of choroidal thickness among Hispanics, useful for eye research among Latin American population. We have evidence of unbiasedness of our results, but we will increase the precision with sample size. Regardless, the clinical meaningfulness of the increased choroidal thickness among Hispanics compared to non-Hispanics warrants future exploration.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.