ObjectiveTo observe the changes of peripapillary vessel density and retinal nerve fiber layer parameters (RNFL) in diabetic mellitus (DM) patients with early diabetic retinopathy (DR).MethodsA retrospective clinical study. From January to December 2018, twenty-eight DM patients (47 eyes, DM group) and 20 normal subjects (40 eyes, control group) in Eye Hospital of Wenzhou Medical University at Hangzhou were included in the study. There was no significant difference between the two groups in age (t=－1.397, P=0.169) and sex composition ratio (χ2=0.039, P=0.843). The optic nerve head was scanned by OCT angiography (OCTA) with HD 4.5 mm ×4.5 mm imaging scanning mode for all subjects. The peripapillary radial peripapillary capillaries vessel density (ppVD) and peripapillary retinal nerve fiber layer (pRNFL) thickness were measured. The changes of ppVD and pRNFL thickness between the two groups were observed. Pearson correlation analysis was used to analyze the correlation between ppVD and pRNFL in each quadrant.ResultsCompared with the control group, the mean ppVD and superior-hemi part, inferior-hemi part, superior, nasal, inferior and temporal quadrant ppVDs of DM group were all significantly lower than those of control group (t=5.107, 4.360, 3.713, 4.007, 2.806, 4.046, 2.214; P＜0.05). The mean and all quadrants pRNFL thickness were lower in eyes of DM group compared with the control, and the superior and inferior quadrant pRNFL thickness were statistically significant (t=2.117, 2.349; P＜0.05), while the mean pRNFL and superior-hemi, inferior-hemi part, nasal and temporal quadrant were not statistically significant (t=1.867, 1.717, 1.869, 0.720, 0.303; P＞0.05). Pearson correlation analysis showed that the significant high-positive correlation was found between ppVD and pRNFL thickness in the nasal quadrant (r=0.734, P＜0.001).ConclusionIn early DR patients, ppVD decreased and pRNFL thinned.
ObjectiveTo observe the flow density (FD) of macular and optic disc and area of foveal avascular zone (FAZ) in severe nonproliferative diabetic retinopathy (S-NPDR).MethodsA prospective cross-sectional study. From October 2019 to April 2020, 31 eyes of 25 S-NPDR patients (S-NPDR group) who were diagnosed in the ophthalmological examination of Jiangsu Province Hospital and 30 eyes of 30 age- and sex-matched healthy volunteers (control group) were included in this study. Optical coherence tomography angiography (OCTA) was used to scan the macular area of 6 mm×6 mm and optic disc of 4.5 mm×4.5 mm. The software automatically divides it into three concentric circles centered on the macular fovea, which were foveal area with a diameter of 1 mm, parafoveal area of 1 to 3 mm, and foveal peripheral area of 3 to 6 mm. The area around the optic disc was divided into 8 areas: nasal upper, nasal lower, inferior nasal, inferior temporal, temporal lower, temporal upper, superior temporal and superior nasal. The FD of the optic disc, the superficial capillary layer (SCP) and deep capillary layer (DCP) of the retina and FAZ area were measured. The FD and FAZ area were compared between the two groups by independent sample t test. The correlation between FAZ area and FD was analyzed by Pearson correlation.ResultsIn parafoveal and perifoveal area, compared with the control group, the FD of SCP (t=6.470, 5.220; P＜0.001) and DCP (t=7.270, 7.370; P＜0.001) decreased in S-NPDR group. In foveal area, there was statistically significant difference in the FD of DCP between the two groups (t=2.250, P=0.030), while the difference in FD of SCP between the two groups was not statistically significant (t=0.000, P=0.900). The FAZ area in S-NPDR group was larger than that in control group, and the difference was statistically significant (t=2.390, P=0.030). The FD in the S-NPDR group was lower than that in the control group except the superior nasal, the difference was statistically significant (t=7.520, 5.000, 4.870, 3.120, 2.360, 2.120, 5.410, 5.560, 2.640; P＜0.05). Pearson correlation analysis showed that the FAZ area of S-NPDR was negatively correlated with FD of SCP (r=－0.513, P=0.004), and had no correlation with FD of DCP (r=0.034, P=0.859).ConclusionThe overall FD in macular area and optic disc of patients with S-NPDR decreased and the FAZ area enlarged.
ObjectiveTo observe the changes of blood flow density in the macular area of normal eyes, and to analyze its correlation with age. MethodsA cross-sectional study. Two hundred and fifty normal healthy subjects (125 males and 125 females, aged 44.76±14.77) in routine ophthalmologic examination at the Department of Ophtalmology of Guangdong Provincial People’s Hospital during June 2017 to June 2018 were enrolled. Among them, 20 to 29, 30 to 39, 40 to 49, 50 to 59, and ≥ 60 years old were 50 subjects (50 eyes) in each. BCVA, slit lamp microscope, indirect ophthalmoscope, OCT angiography (OCTA) examinations were conducted for all eyes. The subjects were examined by both eyes, and the data of 1 eye was selected by EXCEL to generate random numbers, including 126 right eyes and 124 left eyes. The range of 6 mm × 6 mm in the macular area was scanned using a frequency domain OCTA instrument. The software automatically divides it into three concentric circles centered on the macular fovea, which were foveal area with a diameter of 1 mm, parafoveal area of 1 to 3 mm, and foveal peripheral area of 3 to 6 mm. The blood flow density of superficial capillary vessel, deep capillary vessel and foveal avascular area (FAZ) within a 300 μm width (FD-300), FAZ area, perimeter (PERIM), non-circularity index, center retinal thickness (CRT) were measured. The relationship between the blood flow density in macula, CRT, FAZ and age was analyzed by Pearson correlation analysis. ResultsThe mean blood flow density of superficial capillary vessel and deep capillary vessel were (51.61±2.54)% and (54.04±5.46)%, respectively. The average FD-300, CRT, PERIM and non-circularity index were (285.55±12.13) μm, (2.150±0.367) mm, 1.10±0.04, respectively. The relevance of the results showed that the age was negatively correlated with the blood flow density of whole area (r=−0.335, −0.279; P＜0.01), parafoveal area (r=−0.255, −0.368; P＜0.01), foveal peripheral area (r=−0.330, −0.269; P＜0.01) in superficial capillary vessel and deep capillary vessel as well as FD-300 (r=−0.311, P＜0.01), but not correlated with the blood flow density of foveal area (r=−0.071, −0.118; P=0.264, 0.064). There was no relationship between the age and the FAZ area, PERIM, non-circularity index (r=−0.070, −0.055, 0.074; P=0.267, 0.385, 0.142). The age was negatively correlated with the average CRT (r=−0.217, P＜0.01), but not correlated with the CRT in foveal area (r=0.115, P=0.068). The CRT was positively correlated with the blood flow density of superficial capillary vessel and deep capillary vessel in foveal area (r=0.715, 0.653; P＜0.01), but negatively correlated with the FAZ area (r=−0.669, P＜0.01). ConclusionThe capillary blood flow density of macular area in the normal eyes decreases with age.
ObjectiveTo observe the imaging characteristics of optical coherence tomography angiography in macular telangiectasia type 2 (Mac-Tel 2). MethodsA retrospective case analysis. From October 2017 to June 2021, 11 patients (22 eyes) diagnosed as Mac-Tel type 2 by multi-modal imaging in Nanjing Medical University Eye Hospital were included in this study. There were 5 males (10 eyes) and 6 females (12 eyes). The age were 41.61±11.32 years old. All patients underwent the examinations of best corrected visual acuity, indirect ophthalmoscope, fundus color photography, fluorescein fundus angiography (FFA), optical coherence tomography (OCT), and OCT angiography (OCTA). The scope of 3 mm × 3 mm in macular area of eyes was scanned by OCTA. After automatic image processing, the system could provide the blood flow image of capillary layer, deep capillary layer, outer retina, choroidal capillary layer, and the B-scan image. The imaging characteristics were observed. ResultsAmong the 22 eyes, 14 eyes were in the early stage of the disease, and 8 eyes had secondary subretinal neovascularization (SRN) and/or choroidal neovascularization (CNV). FFA examination that in the early stage of the disease, the capillaries near the fovea were dilated, the blood vessels were stretched, and the late fluorescence was mainly stained; high-fluorescence leakage was seen when SRN and CNV were developed. OCTA examination showed that in the early stage of the disease, the temporal capillaries in the macular area were dilated and stretched, especially in the deep layer. The capillary space was enlarged, and the right-angled venules were seen to change and infiltrate into the deep layer; when the lesions invaded the outer retina, flower clusters-like SRN were seen; neovascularization was seen in the outer retina and choroidal capillary layer when CNV was developed. B-scan image showed that in the early stage of the disease, irregular weak reflex cavities and lamellar holes change between the neuroepithelial layers; secondary SRN and CNV showed strong little clumpy reflexes accompanied by abundant blood flow signals. ConclusionThe image characteristics of OCTA in the eyes of Mac-Tel 2 were dilated, stretched superficial and deep temporal capillaries in the macula area and right-angled changes in blood vessels.
Abstract An animal experiment had been conducted for the purpose to find out the possibility of application of instantaneous sustained limited expansion (ISLE). A total of 54 skin defects in 9 pigs were obtained and were divided into two groups. One group of the pigs were subjected to instantaneous sustained limited expansion, the others, as the control group, just received the tension suture. At the same time the blood supply of the skin was measured by laser doppler flowmeter (LDF). It was showed that microcirculatory perfusion of the ISLE group was considerably better than that of the control. Inaddition, the correlation between the blood flow of the skin and the expanding pressure, as well as the pathologic changes of the skin were discussed.
ObjectiveTo compare the choriocapillaris flow density and choroidal vessel volume (CVV) of acute and chronic central serous chorioretinopathy (CSC).MethodsA cross-sectional observational clinical study. A total of 64 eyes of 64 patients (CSC group) diagnosed with CSC at Department of Ophthalmology of West China Hospital of Sichuan University from May 2019 to October 2020, and a total of 64 eyes of 64 age and gender matched healthy volunteers (control group) during the same period were included in this study. In the CSC group, there were 34 patients with acute CSC (acute CSC group) and 30 patients with chronic CSC (chronic CSC group). There was no significant difference in age (t=－0.041) and sex composition ratio (χ2=0.191) between CSC group and control group (P＞0.05). There were statistically significant differences in age (t=－1.872) and sex composition ratio (χ2=8.778) between acute CSC group and chronic CSC group (P＜0.05). Swept source optical coherence tomography angiography (SS-OCTA) was performed using VG200D. The scanning mode was 512×512 and scannig range was 12 mm × 12 mm. The choriocapillaris flow density of the 3 mm, 6 mm, 12 mm circular area and 1-3 mm ring, 3-6 mm ring, and 6-12 mm ring, and the CVV of the of the 3 mm, 6 mm, 12 mm circular area was automatically generated by the built-in software (v1.28.6). The age, choriocapillaris flow density and CVV were compared between two groups using independent sample t test.ResultsCompared with the control group, the choriocapillaris flow density decreased in the CSC group, and there were statistically significant differences in the 3 mm, 6 mm circular area (t=－7.210, －4.040; P＜0.001). There were statistically significant differences between CSC group and control group in the 3 mm, 6 mm, 12 mm circular area (t=1.460, 12.270, 11.250; P＜0.05). Compared with the acute CSC group, the choriocapillaris flow density decreased in the chronic CSC group, and there were statistically significant differences (P＜0.05) in the 3 mm, 6 mm circular area (t=3.230, 2.330), the total and four quadrants of 1-3 mm ring (t=2.780, 2.060, 2.140, 2.620, 3.770), the superior quadrants of the 3-6 mm ring (t=2.550), and the superior and temporal of 6-12 mm ring (t=3.070, 2.610). There was no significant difference of CVV in the 3 mm, 6 mm and 12 mm circular area between the acute CSC group and the chronic CSC group (t=0.250, 0.070, －0.110; P＞0.05).ConclusionCompared with acute CSC, chronic CSC exhibits significant decreased choriocapillaris flow density and no change in CVV.
Objective To observe the hemodynamic changes in the retina and choroid after scleral buckling surgery in eyes with rhegmatogenous retinal detachment (RRD). MethodsA prospective clinical observational study. A total of 25 eyes of 25 patients with RRD who underwent scleral buckling surgery in Tianjin Eye Hospital from February to April 2024 were included in the study. Among them, 10 were male and 15 were female. Age was 17-68 years old. All cases were monocular. The surgical eye and the contralateral healthy eye were divided into the affected eye group and the contralateral healthy eye group respectively. Best corrected visual acuity (BCVA), scanning source optical coherence tomography angiography (SS-OCTA), and axial length (AL) measurements were performed 3 months after surgery. SS-OCTA examination of macular area was performed by VG200 of Visual Microimaging (Henan) Technology Co., LTD. Scanning range 21 mm×26 mm. According to the partitioning method of the early treatment group of glycosuria retinopathy, the retina within 21 mm of the macular fovea was divided into concentric circles with the macular fovea as the center and diameters of 1-3, 3-6, 6-12, 12-21 mm, respectively. The built-in software of the device was used to record the central area (12 mm×12 mm in the fovea of the macula) and the peripheral area (12-21 mm range) retinal superficial capillary plexus (SCP), deep capillary plexus (DCP), radial peripapillary capillaries (RPC) blood density and choroidal vascular index (CVI), choroidal vascular volume (CVV), and 1-3, 3-6, 6-12, 12-21 mm above concentric circles (S), nasal side (N), temporal side (T), and lower side (I) SCP, DCP, and RPC blood flow density. Quantitative data between the two groups were compared by independent sample t test or Wilcoxon signed rank test. The correlation between retinal and choroid blood flow parameters and postoperative BCVA was analyzed by Spearman correlation analysis. ResultsCompared with the opposite healthy eye group, SCP blood density in the central area (Z=−4.372), DCP blood density in the central area (Z=−2.829), and CVI in the peripheral area (Z=−2.138) were decreased in the affected eye group, and the differences were statistically significant (P＜0.05). SCP: in the affected eye group, the blood flow density in T3-6 mm, T6-12 mm, N6-12 mm and T12-21 mm regions decreased, while the blood flow density in I6-12 mm regions increased, with statistical significance (P＜0.05). DCP: blood flow density in S6-12 mm, I6-12 mm, S12-21 mm and I12-21 mm regions decreased significantly, and the differences were statistically significant (P＜0.05). RPC: blood flow density decreased significantly in T6-12 mm and I12-21 mm, and the differences were statistically significant (P＜0.05). CVI: T6-12 mm, S12-21 mm, T12-21 mm, I12-21 mm significantly decreased, and T1-3 mm, S12-21 mm significantly increased, the differences were statistically significant (P＜0.05). Correlation analysis showed that AL growth was positively correlated with CVV in central region (r=0.408, P=0.040) . The number of pad pressure was negatively correlated with the blood density of central DCP (r=−0.422, P=0.030). ConclusionsAfter scleral buckling operation, the blood flow density and choroidal blood flow parameters in RRD affected eyes are lower than those in contralateral healthy eyes in some areas. The increase of AL is positively correlated with CVV in the central region, and the wider the range of pad pressure, the worse the recovery of DCP blood density.
Objective To observe the changes of macular microvascular structure and macular pigment density (MPOD) in eyes with macular edema (ME) secondary to retinal vein occlusion (RVO), and preliminarily analyze their correlation. MethodsA prospective clinical study. A total of 62 eyes of 62 patients with monocular RVO secondary ME (RVO-ME) diagnosed in the Ophthalmology Hospital of Xi'an No.1 Hospital from July 2020 to May 2021 were included in this study. There were 33 males with 33 eyes, 29 females with 29 eyes. The age was 58.30±12.15 years. The course of disease from the onset of symptoms to medical treatment was 12.29±7.65 days. All patients underwent best corrected visual acuity (BCVA), optical coherence tomography angiography (OCTA) and MPOD test. BCVA examination was performed using a standard logarithmic visual acuity chart, which was converted to logarithm of minimum angle of resolution (logMAR). The vascular density (VD), vascular skeletal density (SD), foveal avascular area (FAZ) and central macular thickness (CMT) of the superficial retinal capillary plexus (SCP) in the range of 3 mm×3 mm in the macular area of bilateral eyes were measured by OCTA. MPOD was measured by heterochromatic scintillation photometry. Bilateral eyes passed examination in 37 cases. The eyes of 25 patients failed to pass the test. The changes of macular VD, SD, FAZ area, CMT and MPOD between the affected eyes and the contralateral eyes were compared. The MPOD of the affected eye and the contralateral eye was compared by paired t test. FAZ area, CMT, VD, SD, and logMAR BCVA were tested by paired Wilcoxon signed rank sum test. Spearman rank correlation test was used to analyze the correlation between macular blood flow density (VD, SD) and foveal morphology (FAZ area, CMT) with logMAR BCVA and MPOD. ResultsCompared with contralateral eyes, VD (Z=－5.981) and SD (Z=－6.021) were decreased, FAZ area (Z=－2.598) and CMT (Z=－6.206) were increased, and the differences were statistically significant (P＜0.05). In 37 patients who passed MPOD test in bilateral eyes, the MPOD value of the affected eye was lower than that of the contralateral eye, and the difference was statistically significant (t=－2.930, P＜0.05). Compared with the affected eye which failed to pass the MPOD detection, macular VD (Z=－2.807) and SD (Z=－2.460) were increased, FAZ area (Z=－4.297) and CMT (Z=－3.796) were decreased in the affected eye which passed the MPOD test, and the differences were statistically significant (P＜0.05). Correlation analysis showed that logMAR BCVA in the affected eye was negatively correlated with macular VD and SD (r=－0.298, －0.461; P＜0.05), which was positively correlated with FAZ area and CMT (r=0.487, 0.789; P＜0.05). MPOD in the affected eye was negatively correlated with logMAR BCVA (r=－0.344, P＜0.05). MPOD in the contralateral eye was positively correlated with CMT (r=0.358, P＜0.05). ConclusionsThe VD and SD of macular SCP are decreased, FAZ area is enlarged, CMT is thickened, and MPOD is decreased in RVO-ME eyes. MPOD is negatively correlated with logMAR BCVA.
ObjectiveTo observe the changes of microperimeter and OCT angiography (OCTA) in idiopathic macular hole (IMH) before and after operation, and to explore the correlation between the changes and visual acuity.MethodsFrom January 2018 to January 2019, 41 patients (41 eyes) with IMH who underwent pars plana vitrectomy (PPV) with or without internal limiting membrane (ILM) flap surgery in Tianjin Eye Hospital were included in this study. Among them, 8 patients (8 eyes) were male and 33 patients (33 eyes) were female. The average age was 64.02±6.46 years. The average course of disease was 7.00±8.85 months. BCVA, microperimeter and OCTA were performed. The retinal mean sensitivity (RMS) at 10 ° and fovea 2 ° fixation rate (P1) and binary contour ellipse area (63% BCEA) were measured by macular integrity assessment instrument. The central retinal thickness (CRT), choroidal blood flow area (CFA), superficial and deep retinal blood flow density (FAVD, FDVD), foveal avascular zone (FAZ) and blood flow densitywithin the width of FAZ 300 μm (FD-300) were measured by OCTA. Twenty one and 19 eyes with or without ILM flap operation were treated with 25G standard three incision PPV. The follow-up time was more than 6 months. Paired t-test was used to compare the indexes before and after operation. Pearson correlation analysis was performed for the correlation between logMAR visual acuity and microperimeter variables and OCTA variables. Nonparametric test was performed for paired comparison between affected eyes and contralateral eyes before and after operation.ResultsAt 6 months after operation, logMAR visual acuity (t=－12.33), RMS (t=7.94), P1 (t=3.21), 63% BCEA (t=－3.98), CRT (t=－9.17), CFA (t=8.14), FSVD (t=3.75), FDVD (t=3.88) were significantly improved compared with those before operation (P＜0.001). The difference of FAZ area (t=－1.40) and FD-300 (t=1.95) before and after operation were not statistically significant (P＞0.05). The results of correlation analysis showed that logMAR visual acuity 6 months after surgery was correlated with preoperative logMAR visual acuity, MIN, RMS, P1, 63% BCEA, FSVD, FDVD and FAZ (r=0.432、0.527、－0.410、－0.383、0.349、－0.406、－0.373、0.407; P＜0.05). At 6 months after operation, the indexes of the affected eyes were significantly improved compared with those before operation, but worse than those of the contralateral eyes (P＜0.05).ConclusionsPPV for IMH can effectively improve the visual acuity, retinal function and foveal microvascular circulation. Retinal function and blood circulation changes have a significant impact on postoperative visual acuity.
Objective To explore the clinical application and effect of infrared thermal imager in blood flow monitoring after skin flap surgery by comparing with skin-contact thermometer. Methods Fifty patients who had undergone flap repair in the microsurgery ward of Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine between October 2019 and October 2020 were enrolled. An infrared thermal imager (FLIR ONE Pro) and a skin-contact thermometer were applied to monitor the skin temperature change till 7 d after surgery. The time consumed of using infrared thermal imager and skin-contact thermometer by different nurses, the efficacy of flap temperature monitoring of the two devices, the temperatures at different time points by using the two devices, and the temperatures under different distances to the flaps by using infrared thermal imager were compared. Results Different nurses had no difference in operating either of the two devices (P>0.05). It took significantly less time to measure the temperature of the flap area with the infrared thermal imager than using skin-contact thermometer [(39.28±3.52) vs. (103.85±9.09) s, P<0.001]. The skin temperature measured by the infrared thermal imager was significantly higher than that by the skin-contact thermometer (P<0.001), and the skin temperature measured by the infrared thermal imager at a height of 30 cm was higher than that at a height of 50 cm (P=0.006), but the temperature change amplitudes were both stable. Conclusions Infrared thermal imager is superior to skin-contact thermometer in terms of temperature measurement time, ease of operation, and sensitivity to temperature changes after skin flap operations. The thermal image collected by infrared thermal imager can provide an important basis for the identification of flap vascular crisis. It is a visual and objective blood supply monitoring equipment.