Research on attention mechanism and loss function based on YOLOv5 to improve the detection method of underground personnel wearing safety helmets.

A 45-year-old man was referred for evaluation of an accessory parafoveal depression adjacent to the fovea. Visual acuity was 6/6 bilaterally with normal anterior segments. Fundoscopy revealed subtle temporal foveal depressions adjacent to the central foveae. Spectral-domain OCT demonstrated two distinct foveal pits in each eye: a deep central fovea and a shallower temporal fovea (). The temporal fovea exhibited grade 1 foveal hypoplasia features, including continuation of inner retinal layers at the foveola, outer nuclear layer widening and outer segment lengthening (, ). OCT-angiography showed paired foveal avascular zones, with the temporal FAZ smaller than the central FAZ, reflecting incomplete vascular remodeling. Bifoveate retinas in humans is exceptionally rare. To date, only three prior cases have been reported, termed “accessory fovea,” or “foveal pseudoduplication.” (-). These cases were predominantly unilateral, although one bilateral case has been described; all showed incomplete inner retinal displacement at the accessory site and were considered nonfunctional with respect to fixation or high-acuity visual processing. Our case represents an example of bilateral bifoveation with well-developed fovea architecture, resembling the bifoveate visual system of birds and reptiles, particularly lizards, which possess both deep central foveae and shallow temporal foveae with retained inner retinal layers (-). These grade 1 hypoplasia characteristics (shallow pit, inner retinal layer continuation, outer segment lengthening, smaller FAZ) (), mirror lizard temporal foveae, where retention of all retinal layers serves distinct binocular vision functions (). This suggests a secondary zone of partial foveal specification undergoing incomplete developmental progression.