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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.Methods:A 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. Results:Compared 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). Conclusions:The 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.
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Objective:To analyze the superficial retinal blood flow around the optic disc of optical coherence tomography angiography (OCTA) in non-arteritic anterior ischemic optic neuropathy (NA-AION) patients with affected eyes and contralateral healthy eyes, compared with healthy people.Methods:From May 2018 to may 2019, 30 patients with NA-AION in Xi′an No. 1 Hospital were selected. The changes of superficial retinal blood flow density and perfusion around the optic disc on OCTA of 30 patients with NA-AION, whose contralateral healthy eyes were compared. The pattern visual evoked potential (PVEP) of both eyes was also compared. 30 healthy people with no history of eye disease and history of eye surgery were selected as healthy control group, and differences between healthy control group and contralateral healthy eye group in NA-AION patients of the superficial retinal blood flow density and perfusion around the optic disc were compared.Results:The average values of serum homocysteine, apolipoprotein E and low density lipoprotein in 30 patients with NA-AION were higher than the normal reference range. Compared with the contralateral healthy eyes, the effected eyes of NA-AION patients had lower retinal blood flow density and perfusion in the center, inner layer and complete area of the optic disc, with significantly difference ( P<0.05); there was no significant difference in the latency and amplitude of PVEP-P100 between the two groups ( P>0.05). There was no significant difference in the density and perfusion of superficial retinal blood flow in the center, inner layer and complete area of the optic disc between the contralateral healthy eyes of NA-AION patients and healthy control ( P>0.05). Conclusions:OCTA is a safe, rapid and non-invasive test, and it can detect blood perfusion defects promptly, which can be used as the most commonly test method for patients with NA-AION in order to make auxiliary diagnosis and gain time for clinical treatment.
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Objective This study compares a dual-freeze protocol with a triple freeze protocol for hepatic cryoablation in the Tibetan pig model.Method Cryoablation with a dual-(10-5-10-5 min)and triple-freeze (5-5-5-5-10-5 min) protocol for the normal livers of 9 Tibet pigs was performed under exposed operation.Temperature changes of cryoprobes and diameter changes of iceballs were measured during the ablation,and seven days later the pathological changes of cryozones were reviewed and the surface and depth cryolesions were measured.Results Compared with cryoablation with two freeze-thaw cycles,there was a greater iceball diameter for cryoablation by three freeze-thaw cycles.Also,seven days after cryosurgery,there were similar surface and deep cryolesions in dual-and triple-freeze protocols.Pathologically,the triple freezing protocol was associated with a longer zone of complete necrosis.Conclusions With the same freezing time (20 min),the triple-freeze protocol may become a more powerful liver-ablation method in cryosurgical application.
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Objective To observe the adverse reaction, tumor response and short term outcomes of percutaneous cryoablation for locally advanced pancreatic cancer, and investigate its feasibility. Methods Fifty-nine consecutive patients with locally advanced, unresectable pancreatic cancer underwent percutaneous cryoablation at our hospital from Sept. 2008 to Sept. 2009, were prospectively studied. Percutaneous cryoablation was performed with an argon/helium-based cryosurgical system under the guidance of ultrasound.Freezing probe was inserted into the center of pancreatic mass and two cycles of freezing were performed with each cycle for 5 min and temperature at-160℃, then the temperature was returned to normal for 10 min.Serum amylase was detected before operation and 1 to 7 days postoperatively. CT or PET-CT scanning was performed for evaluation of tumor response every 4 to 6 weeks after cryoablation. Survival was assessed by Kaplan-Meier method. Results 59 patients had a total of 76 biopsy-proven tumors, which were located at the pancreas head (n = 56), body (n = 7), and tail (n = 13). The median size of tumor was 4.5 cm (range 3 ～6 cm). Nineteen patients had liver metastases. Postoperative abdominal pain occurred in 45 cases (76.3%),fever occurred in 29 cases (49.2%) and elevation of serum amylase occurred in 34 cases (57.6%). Severe complications including intra-abdominal bleeding, pancreatic leaks, ileus, and metastasis by probe tract occurred in 5 cases (8.5%). There was no death associated with cryoablation. The median hospital stay was 21 days. 2 patients (3.4%) achieved complete response, 23 patients (39.0%) achieved partial response,30patients (50.8%) had stable disease, 4 patients(6.8%) had progressive disease. The median survival was 8.4 months. The overall survival at 3, 6 and 12 months was 89.7%, 61.1% and 34.5%, respectively.Conclusions Ultrasound-guided percutaneous cryoablation appears to be a safe and feasible, minimally invasive technique for locally advanced pancreatic cancer.