Published online Aug 16, 2023. doi: 10.12998/wjcc.v11.i23.5479
Peer-review started: April 14, 2023
First decision: July 3, 2023
Revised: July 11, 2023
Accepted: July 27, 2023
Article in press: July 27, 2023
Published online: August 16, 2023
In children, general fundus examination is often obtained hardly because of it required to acquire images with the contact lens-based Retcam and general anesthesia. optical coherence tomography angiography (OCTA) may provide a noninvasive and reliable approach for evaluating macular perfusion in children. Tibet, as “the roof of the world”, its environmental factors such as low atmospheric oxygen, low humidity, strong ultraviolet radiation, and low temperatures are prevalent. People lived Tibet suffered from a range of symptoms prompted by oxygen deficiency which leaded to ocular disorders or blood disorders. These changes of macular microvasculature during childhood remain unclear.
OCTA as one of the combined series of screening methods have high accuracy and reliability in assessing children’s ocular health. People lived in Tibet from a range of symptoms prompted by oxygen deficiency, such as ocular disorders or blood disorders. Relatively little is known about the development of vascular circulation in the macular region in childhood, especially in high altitude environment. This research helps fill data in gaps in healthy children and extreme weather.
To quantify the macular micro-vasculature in healthy children of various ages using OCTA in Qamdo. To compared the gender, age, environment and other influence factors in children’s retinal growthing.
Based on local government evaluations, 9 schools from 4 different areas in Qamdo, totally 347 students were stratified into 10 levels (from Grade One to Second year of Senior High School). The Cirrus 5000 OCT-A device (Carl Zeiss Meditec, Dublin, CA, United States) was first used to performed on a 3 mm × 3 mm area centered on the macular region and macular cube 512 × 128 showed details in macular in Tibet. ETDRS Vessel Flow Density (VD) of the macular central vascular plexus density (CVD), inner vascular plexus density (IVD), full vascular plexus density (FVD), and the size of the foveal avascular zone (FAZ) were measured. The differences were compared among various ages, sexes and living environments.
The mean FAZ area in all eyes was 0.27 mm2 ± 0.12 mm2. The mean foveal thickness (MFT) in the macular cube was 227.64 μm ± 23.51 μm. Compared with girls, boys had a lager FAZ (P = 0.0029). Among the different age groups, MFT (P < 0.001) and FVD (P < 0.0001), IVD (P < 0.0001) and CVD (P = 0.0050) increased with age. FAZ areas were not correlated with age (P = 0.8853) or others (MFT, area).
We expanded the microcirculation database in children from 5 to 18 years old using OCTA in averages altitude above 3000 m. We know the MFT was thinner in girls than in boys. Age effect in MFT, FVD, IVD, and their relationship is linear increased. High altitude might cause difference in MFT.
Because our sample size is small, future studies will need a larger population-based study design, exploring the effects of age, sex, and important factors such as axial eye length, IOP, race and ethnicity. We will have a further study to compared those data in Chongqing (400 m). Next step we will also collecting the information from same samples and make a follow-up study, and try to analysis some special samples like myopia infused in OCTA. The effects of sunlight exposure time and oxygen concentration on the thickness in Tibetan children should be observed and explored in subsequent examinations and studies. Our term tries to build a platform about ophthalmic information in Southwest of China. Further studies are needed to determine the mechanisms and clinical significance of these changes.