Objective To investigate the early influences of laser photocoagulation on macular retinal thickness in diabetic retinopathy(DR). Methods Optic coherence tomography examination was performed in 30 eyes with DR(phase Ⅲ~Ⅳ) before, and on the 3rd day and the 7th day after photocoagulation respectively. The thickness of neuroretina and pigment epithelium were measured in the areas of fovea macula and 750 μm from fovea macula. Results Three days after photocoagulation, significant thickening of neuroretina was observed in the fovea macula, which is positively related with age, fasting blood sugar and duration of DR. There was no significant changes in the thickness of pigment epithelium in macula and in the thickness of neuroretina 750 μm from fovea macula. Conclusion Significant thickening of neuroretina in fovea macula in DR early after photocoagulation reveals progressed macular edema induced by photocoagulation which is positively related with age, fasting blood sugar and duration of DR. (Chin J Ocul Fundus Dis, 2002, 18: 31-33)
ObjectiveTo investigate the course of the idiopathic macular hole (IMH) clinically diagnosed as at stage Ⅰ-Ⅳ by optical coherence tomography (OCT), and analyze the relationship between the posterior vitreous detachment (PVD) and the course of IMH. MethodsHadn′t undergone any operation, periodical OCT were performed on 72 eyes of 58 patients with IMH at stage Ⅰ-Ⅳ confirmed by Gass standard and the features of OCT images.ResultsThe longest follow-up period was 43 months (average 13.4 months), and the examine times of OCT on each eye were between twice to 10 times (average 4.7 times). During the followup period, 23 eyes were in stage I in which 9 (39.1%) developed to stage II and 2 had recovered normal curve of fovea after PVD; 19 were in stage II in which 13 (68.4%) developed to Ⅲ-Ⅳ and 1 had closed hole after PVD; 11 were in stage III in which 5 (45.5%) developed to stage IV and 1 had partly closed hole 12 months later. The images of OCT showed that the process of macular hole was consistent with the course that vitreous depart from retina from the circumference of fovea till entire posterior detachment.Fifteen affected eyes in this series of patients had undcrygong surgical treatment due to serious progression of IMH in follow-up period. ConclusionsThere is a close relationship between the formation and development of macular hole and the occurrence of PVD. OCT can show the progress of the macular hole directly and offer an important technique in diagnosis, classification and surgical treatment of IMH. (Chin J Ocul Fundus Dis, 2005,21:79-82)
Objective To evaluate the application value of optical coherence tomography angiography (OCTA) in obstructive sleep apnea syndrome (OSAS). Methods A comprehensive search of both domestic and international databases was conducted to identify clinical studies on the use of OCTA in OSAS, from the establishment of the databases to May 2024. A meta-analysis was performed using Revman 5.4 software. Results A total of 134 studies were initially identified, with 14 studies meeting the inclusion criteria, encompassing 999 subjects (739 in the OSAS group and 260 in the healthy group). Meta-analysis results indicated that the superficial capillary plexus (SCP) density in the fovea (MD=–2.05, 95%CI –3.75 to –0.35, P=0.02) and parafovea (MD=–1.56, 95%CI –2.44 to –0.68, P=0.000 5) was significantly lower in the OSAS group compared with the healthy group. In the mild to moderate OSAS group, SCP density was significantly lower in the fovea (MD=–2.41, 95%CI –4.32 to –0.49, P=0.01), parafovea (MD=–1.17, 95%CI –2.01 to –0.32, P=0.007), and perifovea (MD=–1.73, 95%CI –2.69 to –0.77, P=0.000 4) compared with the healthy group. In the severe OSAS group, SCP density in the perifovea (MD=–1.33, 95%CI –2.53 to –0.13, P=0.03) was significantly lower than that of the healthy group. SCP density in the whole area (MD=0.36, 95%CI 0.05 to 0.68, P=0.02) was significantly higher in the mild to moderate OSAS group compared with the severe OSAS group. In the deep capillary plexus (DCP) density, the OSAS group showed significantly lower densities in the whole area (MD=–2.16, 95%CI –3.51 to –0.81, P=0.002), fovea (MD=–2.38, 95%CI –4.38 to –0.37, P=0.02), and parafovea (MD=–2.33, 95%CI –3.93 to –0.73, P=0.004) compared with the healthy group. The mild to moderate OSAS group also showed significantly lower densities in the whole area (MD=–2.02, 95%CI –3.33 to –0.72, P=0.002) and parafovea (MD=–1.65, 95%CI –3.04 to –0.26, P=0.02) compared with the healthy group. The severe OSAS group had significantly lower DCP density in the whole area (MD=–2.26, 95%CI –3.85 to –0.66, P=0.006) and parafovea (MD=–1.47, 95%CI –2.31 to –0.62, P=0.000 7) compared with the healthy group. DCP density in the whole area (MD=0.54, 95%CI 0.02 to 1.07, P=0.04) was significantly higher in the mild to moderate OSAS group compared with the severe OSAS group. Regarding the retinal nerve fiber layer (RNFL) thickness, the inferior quadrant (MD=4.01, 95%CI 0.69 to 7.32, P=0.02) and temporal quadrant (MD=4.35, 95%CI 1.88 to 6.82, P=0.000 6) were significantly thicker in the mild to moderate OSAS group compared with the severe OSAS group. In terms of the foveal avascular zone (FAZ) area, the severe OSAS group showed a significantly larger FAZ area (MD=0.06, 95%CI 0.03 to 0.08, P<0.000 01) compared with the healthy group. Conclusion OCTA-related ocular biomarkers may be associated with the occurrence and progression of OSAS and have potential applications in the diagnosis and treatment of OSAS.
Objective To observe the characteristics of the images of optical coherence tomography (OCT) performed on the patients with macular edema, and investigate relationship between the retinal thickness at the central fovea and the best corrected visual acuity. Methods Fourty-seven patients (54 eyes) with macular edema diagnosed by direct and indirect ophthalmoscopy, three mirror contactlens, or fundus fluorescein angiography (FFA) underwent OCT which was also performed on 50 healthy individuals as the control. The examination focused on the horizontal and vertical planes crossing the central fovea to measure the thickness of the fovea. The correlation between retinal thickness at the central fovea and best-corrected visual acuity was analyzed, and the images of OCT in the patients with macular edema were classified according to the macular configuration. Results Significant difference of the macular configuration and best-corrected visual acuity was found between the control and macular edema group. Three characteristics were found in the images of OCT in the patients with macular edema: sponge-like retinal swelling in 20 eyes (37.1%), macular cystoid edema in 26 eyes (48.1%), and serous retinal detachment in 8 eyes (14.8%). The statistical analysis showed that there was a negative correlation between the thickness at the central fovea and best-corrected visual acuity of affected eyes (r=-0.569, P=0.000). Conclusions The images of OCT in macular edema include 3 types: sponge-like retinal swelling, macular cystoid edema, and serous retinal detachment. The retinal thickness at the central fovea of the eyes with macular edema was thicker than that of the normal ones, and the thicker the fovea is, the poorer the visual acuity will be. (Chin J Ocul Fundus Dis，2004，20：152-155)
Purpose To evaluate the surgical effect of idiopathic macular hole (IMH)，with optical coherence tomography (OCT)． Methods To measure the diameter of holes and hole halos，the thickness of hole in edge，the changes of hole pattern in 19 cases (19 eyes) with IMH using OCT． Results By quantitatively measuring，OCT showed that after surgery the mean hole diameter lessened from （570．95plusmn;264．59 ）mu;m to （337．05plusmn;335．95）mu;m．The mean diameter of hole halo lessened from （1043．53plusmn;278．80）mu;m to （695．00plusmn;483．00）mu;m and the mean thickness of the hole edge thinned from （389．78plusmn;60．58）mu;m to （298．78plusmn;109．80）mu;m．In 17 eyes the holes become closed or reduced in size or the hole halo，and thinned in hole edge．The anatomic successful rate of the surgery is 89%． Conclusion OCT can objectively，accurately and effectively judge the anatomic effect of IMH surgery． (Chin J Ocul Fundus Dis，2000，16：71-138)
ObjectiveTo use flash electroretinogram (F-ERG) and optical coherence tomography (OCT) to examine patients with primary retinitis pigmentosa (RP), and analyze the specificity of the disease on F-ERG and OCT. MethodsThirty-seven patients (74 eyes) diagnosed with primary retinitis pigmentosa in the Department of Ophthalmology, West China Hospital between September 2013 to October 2014 and 38 normal volunteers (76 eyes) were included in this study. F-ERG and OCT examinations were performed on all the patients. Then, we analyzed the differences between the two groups of subjects. ResultsFor RP patients undergoing P-ERG examination with the dark adaptation of 0.01 ERG, the latency of b wave was (73.24±6.42) ms and the amplitude of b wave was (22.87±22.48) μV; when dark adaptation of 3.0 ERG was adopted, the latency of a wave was (24.57±6.30) ms, the amplitude of a wave was (35.45±25.54) μV, the latency of b wave was (48.19±8.18) ms, and the amplitude of b wave was (119.47±50.89) μV; with the light adaptation of 3.0 ERG, the latency of a wave was (21.01±4.86) ms, the amplitude of a wave was (12.59±13.43) μV, the latency of b wave was (38.43±5.00) ms, and the amplitude of b wave was (27.19±38.12) μV. For normal volunteers undergoing F-ERG examination with the dark adaptation of 0.01 ERG, the latency of b wave was (72.63±3.49) ms and the amplitude of b wave was (86.36±21.57) μV; when the dark adaptation was 3.0 ERG, the latency of a wave was (22.88±1.62) ms, the amplitude of a wave was (210.74±43.57) μV, the latency of b wave was (42.59±2.60) ms, and the amplitude of b wave was (398.29±62.42) μV; when the light adaptation of 3.0 ERG was adopted, the latency of a wave was (16.61±0.87) ms, the amplitude of a wave was (54.26±19.64) μV, the latency of b wave was (33.29±1.11) ms, and the amplitude of b wave was (176.98±63.44) μV. There were no significant differences between the two groups when dark adaptation ERG was 0.01 (P=0.48), but for other adaptations, there were significant differences in the latency and amplitude of a and b wave between the two groups (P<0.05). The results of OCT showed that the retinal thickness of the RP patients with a range of 1 mm diameter centered on macular center concave was (218.66±74.14) mm, 3 mm diameter was (275.03±47.85) mm, and 6 mm diameter was (247.37±46.44) mm. For normal volunteers, OCT showed that the retinal thickness with a 1 mm range centered on macular center concave was (250.38±15.79) mm, 3 mm was (323.64±17.26) mm, and 6 mm was (283.44±12.50) mm. The differences between the two groups were statistically significant for each range (P<0.01). ConclusionFor patients with RP, F-ERG shows latency delay and amplitude decrease for each response, while OCT displays a thinning thickness of macular fovea. Therefore, F-ERG and OCT can not only effectively evaluate the functions of macular and the surrounding retina, but can also be used as an effective method for the diagnosis of RP.
A three-dimensional (3D) model of human anterior chamber is reconstructed to explore the effect of different corneal temperatures on the heat transfer in the chamber. Based on the optical coherence tomography imaging of the volunteers with normal anterior chamber, a 3D anterior chamber model was reconstructed by the method of UG parametric design. Numerical simulation of heat transfer and aqueous humor flow in the whole anterior chamber were analyzed by the finite volume methods at different corneal temperatures. The results showed that different corneal temperatures had obvious influence on the temperature distribution and the aqueous flow in the anterior chamber. The temperature distribution is linear and axial symmetrical around the pupillary axis. As the temperature difference increases, the symmetry becomes poorer. Aqueous floated along the warm side and sank along the cool side which forms a vortexing flow. Its velocity increased with the addition of temperature difference. Heat fluxes of cornea, lens andiris were mainly affected by the aqueous velocity. The higher the velocity, the bigger more absolute value of the above-mentioned heat fluxes became. It is practicable to perform the numerical simulation of anterior chamber by the optical coherence tomography imaging. The results are useful for studying the important effect of corneal temperature on the heat transfer and aqueous humor dynamics in the anterior chamber.
ObjectiveTo systematically review the diagnostic value of optical coherence tomography angiography (OCTA) for primary open-angle glaucoma (POAG). MethodsThe CNKI, WanFang Data, VIP, CBM, PubMed, Embase, Web of Science, and Cochrane Library databases were electronically searched to collect diagnostic test on OCTA for POAG from inception to February 2024. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. Meta-analysis was then performed by using Stata 15.0 software. ResultsA total of 12 diagnostic tests involving 993 subjects were included. Meta-analysis results showed that the sensitivity/specificity of OCTA for diagnosing peripapillary vessel density, retinal vessel density, and optic nerve fiber changes in patients with POAG were 0.77/0.92, 0.56/0.92, and 0.85/0.91, respectively, and the AUC of the SROC curve was 0.94, 0.92 and 0.95, respectively. ConclusionOCTA has high diagnostic accuracy for POAG. Due to the limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.
Purpose To investigate the relationship between the changes of the thickness of retina in macula and the abnormalities in multifocal electroretinog rams (mERG) in diabetic retinopathy. Methods mERG and optical coherence tomography (OCT) examination were performed in 38 patients (60 eyes) with DR (phase Ⅲ～Ⅳ). The data were processed with software SPSS and line relation analysis was done. Results The response densities of N1, P1 and N2 in central 5deg; area was significantly negative related to the thickness of neuroretina in macular fovea (correlation efficient -0.252～-0.266，Plt;0.05). The response density of N2 in central 10deg; area was also significantly negative related to the thickness of neuroretina in macular fovea (correlation efficient -0. 332，P=0.01).There was no significant relationship between the latencies of N1 in central 5deg;, 10deg; area and the thickness of macula, whereares the latenc ies of P1 and N2 in central 5deg; were negatively related to the thickness of retinal pigment epithelium in the macular fovea (correlation efficient-0.271～ - 0.322，Plt;0.05). Conclusion The changes of the thickness of neuroretina in macula may affect the local retinal function in macula, which may be revealed by the reduction of response densities in mERG in patients with diabetic retinopathy. (Chin J Ocul Fundus Dis, 2001,17:257-259)