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        find Keyword "retina" 208 results
        • VITRECTOMY AND SILICONE OIL INJECTION FOR ADVANCED AND COMPLICATED RETINAL DETACHMENT

          Vitrectomy and silicone oil injection were performed for treatment of 43 patients with complicated retinal detachment (RD, n=21 ) or subsequent atrophia bulbi (AB, n=22). Retinal reattachment was achieved in 14 (66.7%) of 21 patients with RD, including 11 with idiopathic proliferative vitreoretinopathy (PVR),6 with traumatic PVR, 3 with congenital uveal coloboma or Marfan syndrome. The visual acuity was better than 0.05 in 7(50%) of successful cases,and better than 0.02 in 11 (78.6%).Only 6(27.3%) patients had retina reattached with visual improvement in 22 cases of AB, including 13 of traumatic PVR,8 of idiopathic PVR.However,the intraoccular pressure was stable and shrinkage of the globe was controlled in 21 (95.5%) of 22 patients with AB.The results indicate that silicone off injection following vitrectomy may provide advanced severe PVR with a chance of successful treatment. (Chin J Ocul Fundus Dis,1994,10:4-6)

          Release date:2016-09-02 06:34 Export PDF Favorites Scan
        • Damages of blood-retinal barrier ultrastructure after infrasound exposure

          Objective To investigate the possible damaging effect of infrasound on ultrastructure and permeability of rats′blood-retinal barrier (BRB). Methods Twenty mature male rats, averagely divided into 5 groups according to the exposure duration, were exposed to infrasound at a 16 Hz frequency and 130 dB sound pressure level in a pressure chamber for 2 hours per day. After exposed for 0, 1 day, 7, 14, and 21 days respectively, ultrastructural changes of rats′ BRB were observed through injection of lanthanum (La) nitrate solution, which was used as a tracer to demonstrate the breakdown of the BRB.Results With prolonging the duration of infrasound exposure, BRB structure lesion, chondriosome tumefaction, endoplasmic reticulum expandedness, membrane disc damage, retinal pigment epithelial cells distortion and putrescence, karyotheca expandedness, and La leakage on each level of retina aggravated gradually.Conclusion Infrasound may cause the breakdown of BRB, and the lesions aggravated with prolonged infrasound exposure time. (Chin J Ocul Fundus Dis,2003,19:46-48)

          Release date:2016-09-02 06:00 Export PDF Favorites Scan
        • Clinical features of retinal detachment in macular spontaneous hemorrhage

          Objective To analyze the clinical features of retinal detachment in macular spontaneous hemorrhage to improve the level of diagnosis and treatment of this disease. Methods The serial clinical data of 23 patients (23 eyes) with subretinal hemorrhage in macular region with the area over 4DDtimes;5DD who were diagnosed in our hospital from Sep, 1998 to Mar, 2003 were analyzed retrospectively. The patients included 12 males (12 eyes) and 11 females (11 eyes) with the average age of 64.1 (47-75). Fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA) and B-scan examination were performed on the patients to analyze the pathogenic factors, and the visual acuity and manifestation of ocular fundus were observed during the 8-24 months followed-up period. Results The visual acuity decreased to less than 0.2 or light perception suddenly in all affected eyes. In 23 eyes, choroidal neovascularization (CNV) of age-related macular degeneration (AMD) was found in 7, polypoidal choroidal vasculopathy (PCV) was in 5, retinal macroaneurysm was in 2, and unknow pathogenic factor in 9. Among the 23 eyes, hemorrhage was absorbed and no cicatritial formation at the fovea in 3 eyes with the visual acuity of 0.4-0.8; scar and pigment proliferation in the hemorrhage area were seen in 12 eyes with the visual acuity of finger counting (FC) to 0.2; combined vitreous hemorrhage was found in 8 eyes, including massive scar in the macular area in 3 who had undergone vitrectomy with the visual acuity of FC/66cm to 0.2 and blindness in the other 5 eyes. Conclusion Spontaneous hemorrhagic retinal detachment always arises in old people whose symptoms were sudden decrease or loss of the visual acuity. The configuration of the hemorrhage is local and diffuse. The prognosis of the visual acuity of most of the patients is poor due to the serious tissue injury in macula area. (Chin J Ocul Fundus Dis, 2006, 22: 228-231)

          Release date:2016-09-02 05:51 Export PDF Favorites Scan
        • The inhibitive effect of adenovirus mediated CD gene and 5-FC on proliferative human retinal pigment epithelial cells

          Objective To study the inhibitive effect of adenovirus mediated CD gene and 5-FC on proliferative human retinal pigment epithelial (HRPE) cells, and to search for an effective method to take precautions against proliferative vitroretinopathy (PVR).Method Different concentrations of CD and 5-FC were added respectively to the cultured third-growth-generation HRPE cells.Transferance rate was detected by positive HRPE cells marked by X-gal and LacZ. The number of HRPE cells were counted and evaluated by methylthiazol-tetrazollium (MTT) method. Results The adenovirus mediated CD gene could be transfered into HRPE cells with a dose-dependent manner. Positive HRPE cells with CD gene could transform 5-FC to 5-Fu,which could inhibit the increase of HRPE cells effectively. No obvious bystander effect on the growth of HRPE cells was detected.Conclusions The adenovirus may introduce a foreign gene into cultured HRPE cells efficiently. It could be a good method to treat and prevent PVR by medication. (Chin J Ocul Fundus Dis,2003,19:168-171)

          Release date:2016-09-02 06:00 Export PDF Favorites Scan
        • Effects of neural retina on development of the structure of outer blood-retinal barrier in embryogenesis

          Objective To investigate effects of neural retina on development of the structure of outer blood retinal barrier in embryogenesis. Methods The retinal neural epithelium (RNE) and pigment epithelium (RPE) layers of 150, 120 and 90 embryonic chicken eyes incubated for 7,10, and 14 days were peeled off. RNE was used to prepare the culture medium with different conditions (7drcSF3, 10drcSF3, 14drcSF3). RPE cells of 7- and 14-incubated chicken embryos were cultured on laminin-coated transwell filter. The SF3, 7drcSF3, 10drcSF3 , 14drcSF3 medium were used respectively in the apical chamber and SF2 was used in basolateral chamber. After the formation of monolayer, the transepithelial electrical resistance of the RPE was detected. After the fixation of RPE cells, the condition of the tight junction among the cells was observed by immunohis tochemistry and transmission electron microscopy. Results For the RPE cells of 7-and 14-day incubated embryonic eyes, the difference of TER in various medium of SF3/SF2, 7drcSF3/SF2, 10drcSF3/SF2, 14drcSF3/SF2 was statistically significant (P<0.01). The polarity of RPE cells was induced and the netlike tight junctional strands was urged in the retina-conditioned medium. Conclusion The neural retina may actively promote the formation of the structure of outer blood retinal barrier. (Chin J Ocul Fundus Dis,2004,20:237-240)

          Release date:2016-09-02 05:58 Export PDF Favorites Scan
        • CHARACTERIZATION OF SEROTONERGIC, 5-HT2 RECEPTORS IN CULTURED RAT RETINAL PIGMENT EPITHELIAL CELLS

          The effects of various receptor agonists/antagonists on the accumulation of inositol phosphates(InsPs) in cultured rat retinal pigment epitheium (RPE) cells were analysed. The results showed that serotonin and the 5-HT2 agonists such as alpha;-methyl-serotonin, quipazine, and DOI (1-[2.5-dimethoxy-4-iodopheny1]-2-aminopropane) all stimulated InsPs accumulation in rat RPE cells. The serotonin-induced stimulation of InsPs was effectively blocked by ketanserin, a 5-HT2 antagonist, but also attenuated by the active phorbol ester PMA (4ft-phorbol 12-myristate 13-acetate), a potent protein kinase C activator.The data presented provide clear evidence for the presence of 5-HT2 receptors coupled to phosphoinositide metabolism on cultured rat RPE cells. (Chin J Ocul Fundus Dis,1994,10:80-83)

          Release date:2016-09-02 06:34 Export PDF Favorites Scan
        • Therapeutic effect of subretinal injection of alteplase plus Conbercept for acute submacular hemorrhage secondary to polypoid choroidal vasculopathy

          ObjectiveTo observe the efficacy and safety of vitrectomy combined with subretinal injection of alteplase (tPA) and intravitreal injection of Conbercept in the treatment of large area submacular hemorrhage (SMH) secondary to polypoidal choroidal vasculopathy (PCV). MethodsA retrospective clinical study. From January to September 2021, 32 eyes of 32 patients with massive SMH secondary to PCV diagnosed in the Affiliated Eye Hospital of Nanchang University were included in the study. Large SMH was defined as hemorrhage diameter ≥4 optic disc diameter (DD). There were 32 patients (32 eyes), 20 males and 12 females. The mean age was (72.36±8.62) years. All patients had unilateral disease.The duration from onset of symptoms to treatment was (7.21±3.36) days. All patients underwent best corrected visual acuity (BCVA) and optical coherence tomography (OCT) examination. BCVA examination was performed using the international standard visual acuity chart, which was converted to the logarithm of the minimum angle of resolution (logMAR) visual acuity during statistics. The central macular thickness (CMT) was measured by spectral domain-OCT. The average size of SMH was (6.82±1.53) DD. The logMAR BCVA 1.73±0.44; CMT was (727.96±236.40) μm. All patients were treated with 23G pars plana vitrectomy combined with subretinal injection of tPA and intravitreal injection of Conbercept. At 1, 3, 6 and 12 months after treatment, the same equipment and methods were used for relevant examinations before treatment. The changes of BCVA and CMT, the clearance rate of macular hemorrhage, and the complications during and after surgery were observed. BCVA and CMT before and after treatment were compared by repeated measures analysis of variance. ResultsCompared with before treatment, BCVA gradually increased at 1, 3, 6 and 12 months after treatment, and the differences were statistically significant (F=77.402, P<0.001). There was no significant difference in BCVA between any two groups at different time points after treatment (P>0.05). Correlation analysis showed that BCVA at 12 months after treatment was negatively correlated with the course of disease (r=-0.053, P=0.774). One week after treatment, macular hemorrhage was completely cleared in 30 eyes (93.75%, 30/32). The CMT was (458.56±246.21), (356.18±261.46), (345.82±212.38) and (334.64±165.54) μm at 1, 3, 6 and 12 months after treatment, respectively. Compared with before treatment, CMT decreased gradually after treatment, and the difference was statistically significant (F=112.480, P<0.001). There were statistically significant differences in different follow-up time before and after treatment (P<0.001). The number of treatments combined with Conbercept during and after surgery was (4.2±1.8) times. At the last follow-up, there was no recurrence of SMH, retinal interlamellar effusion and other complications. Conclusion Subretinal injection of tPA combined with intravitreal injection of Conbercept is safe and effective in the treatment of large SMH secondary to PCV, and it can significantly improve the visual acuity of patients.

          Release date:2024-03-06 03:23 Export PDF Favorites Scan
        • Analysis of visual characteristics with non arteritic central retinal artery occlusion after treatment

          ObjectiveTo observe the changes of central visual acuity and extracentral visual acuity in eyes with non-arteritic central retinal artery occlusion (NA-CRAO). MethodsA retrospective clinical study. From January 1, 2017 to December 31, 2024, 140 patients (140 eyes) diagnosed with NA-CRAO through ophthalmic examination at Department of Ophthalmology of First People's Hospital of Xianyang City were included in the study. All affected eyes underwent best corrected visual acuity (BCVA), visual field, intraocular pressure, fundus color photography, optical coherence tomography (OCT), and fluorescein angiography (FFA) examinations. After a clear diagnosis, conservative treatment such as reducing intraocular pressure, relieving spasms, and dilating blood vessels should be given immediately. Simultaneously, intravenous and/or arterial thrombolysis therapy should be administered based on the patient's overall condition. Under the same treatment conditions as other treatments, 33 eyes were treated with hyperbaric oxygen therapy within 24 hours after seeking medical attention. The changes in central visual acuity (BCVA) and peripheral visual acuity of the affected eye one month after treatment were observed. BCVA improvement of ≥ 1 line was defined as the increase of no light sensitivity to light sensitivity or above, and the increase of light sensitivity to 0.01 or above. The visual acuity outside the center was determined by the 0 ° axis in front of the eyeball at eye level, and was 10 ° outside visual acuity on the temporal side. Multivariate analysis using logistic regression analysis. ResultsAmong the 140 cases (140 eyes), there were 84 males (84 eyes) and 56 females (56 eyes). The mean age was (63.89±10.78) years. The duration of illness from the onset of symptoms to the time of diagnosis was 48 (2-720) hours. 6, 1, 14, 47, 41, 16, and 15 eyes were diagnosed with BCVA without light perception, uncertain light perception, manual/anterior, digital/anterior, 0.01-0.10, and ≥ 0.10, respectively. FFA examination revealed delayed arm retinal circulation time and filling of the retinal artery trunk to the peak, with changes in the "arterial front" observed in 126 eyes. OCT examination showed extensive edema and unclear structure in the inner layer of the retina in all patients. Out of 140 eyes, 122 were treated with intravenous thrombolysis and 4 with arterial thrombolysis; 14 eyes did not receive thrombolytic therapy. After treatment, 38 eyes (27.1%) showed an improvement of BCVA ≥ 1; 67 eyes (47.9%) did not show an improvement in BCVA, and the affected eye had a BCVA of approximately 0.6 without light perception; 17 eyes (12.1%) showed improvement in peripheral vision, and the peripheral vision of the affected eyes ranged from 0.01 to 0.1, all of whom were patients undergoing intravenous thrombolysis, and prior to treatment, this group of patients had complete blindness in the coarse side visual field of the Amsler grid, and their out of center visual acuity could not be measured. Among the 33 eyes treated with hyperbaric oxygen therapy, 24 eyes (72.7%) showed an increase in BCVA after treatment; 9 eyes did not improve, among which 4 eyes (12.1%) showed improvement in out of center visual acuity. Among the 107 eyes that did not receive hyperbaric oxygen therapy, 49 eyes (45.8%) showed an increase in BCVA after treatment. There was no improvement in 58 eyes (54.2%), among which 13 eyes (12.1%) showed an improvement in out of center visual acuity. The results of logistic regression analysis showed that intravenous thrombolysis and hyperbaric oxygen therapy were independent predictive factors for the improvement of central and extra central visual acuity (P<0.05). ConclusionsHyperbaric oxygen therapy within 24 hours of seeking medical attention for patients with NA-CRAO disease course ≤ 1 month has a significant effect on the recovery of central and extra central vision. Intravenous thrombolysis and hyperbaric oxygen therapy are independent predictive factors for the improvement of central and extra central vision.

          Release date:2025-10-16 02:45 Export PDF Favorites Scan
        • Research progress of surgical treatment of myopic foveoschisis

          Myopic foveoschisis (MF) has mild early symptoms, however, its course is progressive. When the secondary macular detachment or macular hole occurs, it can cause severe vision loss. Therefore, it is generally believed that MF patients should undergo surgical intervention early after the onset of symptoms to prevent them from further developing into a macular hole or macular hole retinal detachment.It is generally believed that the traction of the vitreous cortex and posterior scleral staphyloma to the retina plays an important role in the occurrence and development of MF. The operation mode is divided into vitreoretinal surgery and macular buckling, the former release the retinal traction via the vitreous body and the latter reattaches the retina via the extrascleral approach. There is no consensus on whether to perform internal limiting membrane peeling and gas tamponade in vitreoretinal surgery and the fovea-sparing internal limiting membrane peeling has become a hot topic in recent years. Compared with vitreoretinal surgery, macular buckling can release the traction of the retina caused by posterior scleral staphyloma, but it cannot relieve the traction in the tangential direction of the retina. Vitreoretinal surgery and extrascleral surgery seems to make up the shortcomings of both, however, the effect of treatment on patients still needs further verification. In clinical work, it is necessary to conduct individualized analysis of MF patients, weigh the advantages and disadvantages of each operation, and choose the most suitable operation mode for patients with different conditions. In the future, the emphasis of our work is to develop operation mode with great curative effect and less complications.

          Release date:2022-01-19 03:48 Export PDF Favorites Scan
        • Research on exudate segmentation method for retinal fundus images based on deep learning

          Objective To automatically segment diabetic retinal exudation features from deep learning color fundus images. Methods An applied study. The method of this study is based on the U-shaped network model of the Indian Diabetic Retinopathy Image Dataset (IDRID) dataset, introduces deep residual convolution into the encoding and decoding stages, which can effectively extract seepage depth features, solve overfitting and feature interference problems, and improve the model's feature expression ability and lightweight performance. In addition, by introducing an improved context extraction module, the model can capture a wider range of feature information, enhance the perception ability of retinal lesions, and perform excellently in capturing small details and blurred edges. Finally, the introduction of convolutional triple attention mechanism allows the model to automatically learn feature weights, focus on important features, and extract useful information from multiple scales. Accuracy, recall, Dice coefficient, accuracy and sensitivity were used to evaluate the ability of the model to detect and segment the automatic retinal exudation features of diabetic patients in color fundus images. Results After applying this method, the accuracy, recall, dice coefficient, accuracy and sensitivity of the improved model on the IDRID dataset reached 81.56%, 99.54%, 69.32%, 65.36% and 78.33%, respectively. Compared with the original model, the accuracy and Dice index of the improved model are increased by 2.35% , 3.35% respectively. Conclusion The segmentation method based on U-shaped network can automatically detect and segment the retinal exudation features of fundus images of diabetic patients, which is of great significance for assisting doctors to diagnose diseases more accurately.

          Release date:2024-07-16 02:36 Export PDF Favorites Scan
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          2. 射丝袜