ABSTRACT
Purpose: To establish normative data for macular thickness in Chinese aged 30 to 80 years using the swept-source optical coherence tomography (SS-OCT) device.Methods: The study included 290 normal eyes, 430 NDR eyes and 150 DR eyes of community residents aged 30 to 80 years in Guangzhou, China. Mean macular thicknesses in Early Treatment Diabetic Retinopathy Study (ETDRS) subfields, central point thicknesses (CPT), and macular volume was measured by SS-OCT (Triton DRI OCT, Topcon, Tokyo, Japan) and Spectral-Domain OCT (SD-OCT; Heidelberg Engineering, Heidelberg, Germany). We assessed agreement between SS-OCT and SD-OCT measurements by intraclass correlation coefficients (ICC) and Bland-Altman plots. We established a conversion equation relating central subfield (CSF), CPT and macular volume between the two OCT devices.Results: Macular thickness measurements in SS-OCT were significantly thinner than in SD-OCT. The mean CSF thickness in normal eyes measured by SS-OCT and SD-OCT were 227.8 ± 19.4 µm and 260.0 ± 19.7 µm (p < .0001). CSF thickness was a signiï¬cantly difference between genders (SS-OCT: male 237.2 ± 18.8 µm vs female 222.0 ± 17.5 µm, p < .0001). In all three groups, the agreement between SS-OCT and SD-OCT was excellent (all ICC > 0.9). The conversion equations for CSF, CPT and macular volume from SS-OCT to SD-OCT were derived, with over 95% of the predicted values fell within 10% of the actual measurements in DR and NDR eyes.Conclusion: We propose SS-OCT CSF thicknesses of 275 µm for males and 260 µm for females as the minimum criteria for macular edema in Chinese aged 30 to 80 years based on 2 SDs above the mean CSF. SS-OCT measurements were significantly thinner than SD-OCT. We derived equations from converting SS-OCT measurements to SD-OCT equivalents.
Subject(s)
Diabetic Retinopathy/diagnosis , Macula Lutea/pathology , Tomography, Optical Coherence/methods , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Healthy Volunteers , Humans , Macula Lutea/diagnostic imaging , Male , Middle Aged , Organ Size , Prospective StudiesABSTRACT
OBJECTIVE: To evaluate the associations of grip strength with retinal or choroidal thickness in patients with type 2 diabetes mellitus without retinopathy. DESIGN: Observational study-cross-sectional design. SETTING AND PARTICIPANTS: This study included the Chinese patients with type 2 diabetes without retinopathy registered in the community health system in Guangzhou, China. MEASURES: The grip strength in both hands were measured by using a dynamometer. The retinal and choroidal thickness in macular region stratified by Early Treatment Diabetic Retinopathy Study (ETDRS) sectors were measured by a swept-source optical coherence tomography. RESULTS: A total of 1029 patients were included. Both retinal thickness and choroidal thickness decreased with the lower quartile of grip strength. Regression analyses indicated that the average retinal and choroidal thickness increased by 0.14 µm (95% CI: 0.03 to 0.25 µm, p=0.011) and 0.57 µm (95% CI: 0.03 to 1.11 µm, p=0.037), respectively, for each additional kilogram of grip strength following adjustment for age and sex. Further adjustments were made for axial length, haemoglobin A1c, length of time the patient had diabetes, insulin usage, height, weight and systolic and diastolic blood pressure, which resulted in an average retinal and choroidal thickness increase of 0.13 µm (95% CI: 0.02 to 0.24 µm, p=0.024) and 0.65 µm (95% CI: 0.13 to 1.16 µm, p=0.013), respectively, for each additional kilogram of grip strength. Consistent results were obtained in the analyses in ETDRS 9 sectors. CONCLUSION: Lower hand grip strength was found to be significantly associated with thinner retinal and choroidal layers in patients with diabetes. Grip strength may provide a useful and easily administered indicator of retinal status in patients with diabetes.
