ObjectiveTo evaluate whether there are changes in cone cells in patients with pre-clinical hydroxychloroquine (HCQ) retinopathy using an adaptive optics (AO) retinal camera. MethodsA retrospective case-control study. From May 2020 to July 2020, 46 patients who were treated in Department of Rheumatism and Immunology, Hainan Hospital of PLA General Hospital with rheumatic immune diseases were included. All patients had a history of HCQ use and no obvious abnormality was found in fundus examination; 105 healthy people with similar demographic characteristics without a history of hydroxychloroquine were recruited as the control group were included. All subjects received the routine ophthalmological examination including best corrected visual auity (BCVA), spectral-domain optical coherence tomography (SD-OCT), Fundus autofluorescence (FAF), visual field, endoscopy of the cornea, and the measurement of axial length (AL). The BCVA was performed with the Snellen visual acuity chart, and the result was converted to logarithmic minimum angle of resolution (logMAR) visual acuity for statistic. Among the 46 cases, 6 cases were males and 40 cases were females. Age was (42.02±13.81) years old; logMAR BCVA was 0.063±0.015; AL was (23.95±0.726) mm. Visual field, macular SD-OCT, FAF examination showed no abnormality. The average cumulative dose of HCQ was 522.60 (6-1 728) g. rtx1 AO retinal camera was used to collect fundus images of subjects in four quadrants above the retina, nasal side, lower side and temporal side with 3°centrifugation from the fovea in both eyes. The cone density, cone spacing, cone arrangement regularity and the proportion of the nearest cones with 6 (nn=6) were measured in the four quadrants. The density of cone cells between the left and right eyes in case group and control group were compared by paired t test. The density and spacing of cone cells in each quadrant were compared by t test of two independent samples. ResultsCompared with the control group, the cone cell density in the four quadrants of the left eye and the nasal, superior and inferior sides of the right eye in the case group was significantly decreased, and the difference was statistically significant (t=4.247, 2.107, 4.884, 2.254, 2.643, 4.445, 4.116; P＜0.05). The cone spacing in the nasal and temporal sides of the left eye of the patients in the case group was significantly larger than that in the control eye, with statistical significance (t=2.750, 3.318; P＜0.05). Compared with the control group, the regulatign of cone cell arrangement in the left temporal side of the right and left eye in the case group were significantly reduced, the difference was statistically significant (P=0.002, 0.011). The proportion of nn=6 in the inferior and temporal sides of the right eye decreased significantly in the case group, and the difference was statistically significant (P=0.006, 0.032). ConclusionAO retinal imaging can detect the changes of cone cells in the early clinical stage of HCQ retinopathy.
ObjectiveTo observe and analyze the spatial distribution and morphological characteristics of macular photoreceptor cones in eyes with high myopia (HM). MethodsA clinical cross-sectional study. A total of 98 eyes from 55 subjects (aged 20-61 years) with varying degrees of myopia, who visited Eye Center of Beijing Tongren Hospital, Capital Medical University from March to May 2024 were enrolled. All subjects underwent examinations including refractive error, color fundus photography, and axial length (AL) measurement. Confocal scanning laser ophthalmoscopy was utilized to measure the density and diameter of cone cells in the central macula and its superior-temporal, inferior-temporal, superior-nasal, and inferior-nasal regions. Based on the equivalent spherical refractive error (SE), 55 eyes from 98 eyes were divided into the emmetropic and low myopic groups (EM/LM group, SE +0.25 to ?3.00 D) and the HM group (SE≤?6.00 D), with 11 eyes from 18 eyes and 44 eyes from 80 eyes in each group. The differences in cone cell density and diameter between the two groups were compared. The qualitative data between the groups were compared using the χ2 test; linear regression analysis was used to analyze the correlations between refractive error, AL, cone cell density, and diameter. ResultsAmong the 44 cases and 80 eyes in the HM group, 7 were male; the age was (33.66±10.33) years; the AL was (27.51±1.53) mm, and the SE was (?9.09±2.95) D. In the EM/LM group, there were 11 cases and 18 eyes, with 4 being male; the age was (31.00±12.50) years; the AL was (22.86±0.69) mm, and the SE was (?0.68±0.52) D. Compared with the EM/LM group, the AL and SE of the HM group were higher, and the density of cone cells in the superior temporal, superior nasal, inferior nasal, and inferior temporal regions was significantly lower, and the diameters were significantly larger. The differences were statistically significant (P＜0.01). There were no statistically significant differences in age (t=0.73, P=0.47), the proportion of males (χ2=1.20, P=0.23), and the density and diameter of cone cells in the macular center region between the two groups (P＞0.05). After adjusting for age and gender, the linear regression analysis results showed that the density of cone cells in the macular center and surrounding regions was negatively correlated with AL (β=?0.53, ?0.58, ?0.90, ?0.79, ?0.92; P＜0.05), and the diameter was positively correlated with AL (β=0.52, 0.81, 0.92, 0.90, 0.96; P＜0.05); among them, the correlation of cone cell density and diameter in the inferior temporal region with AL was the strongest. ConclusionsIn eyes with HM, there is a decrease in cone density and an increase in cone diameter within the macular and paramacular regions. Regional changes in temporal macular cones are strongly associated with axial elongation.