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        find Keyword "Optic disk" 27 results
        • Optic disc drusen: a review

          Optic disc drusen (ODD) is an acellular deposit located in front of the cribriform of the optic disc. ODD has been much underdiagnosed due to few obvious clinical symptoms. These clinical symptoms are easily confused with optic disc edema caused by systemic high-risk diseases. The current mainstream view is that optic nerve fiber axon metabolism is disordered, leading to intracellular mitochondrial calcification. After axon chronic disintegration, calcified mitochondria continuously release outside the cell, resulting in a much higher concentration of extracellular calcium than inside the cell. The continuous deposit and accumulation of extracellular calcification fuse to small calcified corpuscles, which lead to ODD formation. OCT enhanced deep imaging can detect ODD sensitively, and its image feature is a weak reflection core completely or partially surrounded by a strong reflection edge. ODD is one of the common causes for optic disc crowding. During adolescence, the accumulating calcified bodies buried in the deep optic disc gradually extrude and migrate to the superficial optic disc, which turn into superficial ODD. As a consequence, part of these ODD patients rapidly progress during adolescence and generally become stable in adulthood with anterior ischemic optic neuropathy, or other vascular complications.

          Release date:2020-09-22 04:09 Export PDF Favorites Scan
        • PERIPAPILLARY SUBRETINAL HEMORRHAGE

          PURPOSE:To discuss the clinical characteristics and differential diagnosis of peripapillary subretinal hemorrhage(PPSRH). METHOD:Retrospective analysis of the clinical documents including mainly the ocular manifestations and the findings of fundus fluorescein angiography(FFA)of 37 patients (38 eyes)with PPSRH. RESULTS:In all of these 37 patients,36 were myopes, 31 were young persons ,the average age was 21 years old,and 36 were affected unilaterally. The subretinal hemorrhage revealed itself in 4 types :PPSRH (5 eyes),PPSRH with disc iaemorrhage (21 eyes),PPSRH with vitreous hemorrhage (2 eyes), and PPSRH with disc hemorrhage and vitreous hemorrhage (10 eyes). In the FFA, the hemorrhages showed blocked fluorescence and the optic discs showed irregular hyperfluorescence at the late phase. All of the hemorrhages were absorbed within 3 weeks to 3 months without any treatment. CONCLUSIONS:According to the manifestation of the optic discs in FFA PPSRH might be complicatton of the buried optic disc drusen. (Chin J Ocul Fundus Dis,1997,13: 143-145 )

          Release date:2016-09-02 06:12 Export PDF Favorites Scan
        • Analysis of macular choroidal and retinal pigment epithelium thickness in tilted disc syndrome

          ObjectiveTo observe the macular choroidal and retinal pigment epithelium (RPE) thickness in tilted disc syndrome (TDS). MethodsThis is a descriptive study. Thirty eyes of 22 TDS patients (TDS group) and 30 eyes of 15 normal subjects (control group) were analyzed. Among TDS group, there were 8 males (11 eyes) and 14 females (19 eyes), the average age was (9.00±2.78) years old. The best corrected visual acuity (BCVA) was 0.3-1.0, and the average spherical equivalent degree was (-3.44±2.22) DS. Among the control group, there were 8 males (16 eyes) and 7 females (14 eyes), the average age was (9.33±1.11) years old. The best corrected visual acuity (BCVA)≥1.0, and the average spherical equivalent degree was (-3.18±1.13)DS. The difference of the spherical equivalent degree between two groups was not statistically significant (t=-1.648, P=0.110). Enhanced depth imaging techniques of frequency-domain optical coherence tomography was used to measure the thickness of choroid and RPE at totally 17 sites. There sites included subfoveal, 4 sites each (500, 1000, 1500 and 2000 μm from the fovea) at the horizontal (nasal/temple) and vertical (superior/inferior) directions. ResultsThe subfoveal choroidal thickness was (235.53±51.77) μm and (273.45±60.3) μm in TDS patients and control respectively, the difference was significant(t=-2.612,P=0.011). The difference of the choroidal thickness of the other 8 horizontal sites (F=24.180) and 8 vertical sites (F=23.390) in TDS group was statistically significant (P=0.000). The TDS choroidal thickness of all horizontal sites except nasal 1000 μm site was thinner than corresponding sites of the control group (P<0.05). The TDS choroidal thickness of the subfoveal site and 4 inferior vertical sites was thinner than corresponding sites of the control group (P<0.05). The subfoveal RPE thickness was (32.56±5.00) μm and (36.58±3.60) μm in TDS patients and control respectively, the difference was significant(t=-3.567,P=0.001). The subfoveal RPE thickness was the thickest among other 16 sites in both groups, and the TDS RPE thickness of all sites was thinner than control group, the difference was statistically significant (P<0.05). ConclusionThe choroidal and RPE thickness of TDS patient was thinner than normal subjects.

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        • The characteristics of optical coherence tomography on nonarteritic anterior ischemic optic neuropathy

          Objective To evaluate the changes of optic nerve head (ONH) and the thickness of peripapillary retinal nerve fiber layer (RNFL) in patients with non-arteritic anterior ischemic optic neuropathy (NAION) using optical coherence tomography (OCT). Methods Circular and cross-sectional OCT scans of an area with a diameter of 3.38 mm surrounding the optic disc were performed for 108 eyes (96 cases) with NAION, including 96 eyes (96 cases) in acute edema phase and 41 eyes (37 cases) in resolving phase. Follow-up period was 2 weeks to 24 months, with an average of 6 months. Results The RNFL was thickener with shallow cup or small cups in the acute edema phase. Comparing with the RNFL in the ischemic sector, the thickness of peripapillary RNFL in the nonischemic sector was greater in 59 eyes (59 cases, 61%), lesser in 26 eyes (26 cases, 27%) and no difference in 11 eyes (11 cases, 12%). During the treatment NAION eyes were dynamically observed by OCT. While ischemic edema of the optic disc resolved in about two weeks, non-ischemic edema subsided in 3-6 weeks. After 1 month in the resolving phase, the thickness of peripapillary RNFL in the ischemic sector of 35 cases (95%) was thinner than the thickness of non-ischemic sector and fellow normal controls. After 3 month in the resolving phase, 26 cases (70%) showed thinner RNFL of whole optic disc. Conclusion The thickness of RNFL in NAION patients in acute edema phase is thicker than that in the fellow normal eyes, and is also thicker in ischemic sector than that in non-ischemic sector. In resolving phase, the thickness of RNFL is thinner in NAION eyes than that in the fellow normal eyes.

          Release date:2016-09-02 05:42 Export PDF Favorites Scan
        • Location and segmentation method of optic disc in fundus images based on deep learning

          ObjectiveTo observe and analyze the accuracy of the optic disc positioning and segmentation method of fundus images based on deep learning.MethodsThe model training strategies were training and evaluating deep learning-based optic disc positioning and segmentation methods on the ORIGA dataset. A deep convolutional neural network (CNN) was built on the Caffe framework of deep learning. A sliding window was used to cut the original image of the ORIGA data set into many small pieces of pictures, and the deep CNN was used to determine whether each small piece of picture contained the complete disc structure, so as to find the area of the disc. In order to avoid the influence of blood vessels on the segmentation of the optic disc, the blood vessels in the optic disc area were removed before segmentation of the optic disc boundary. A deep network of optic disc segmentation based on image pixel classification was used to realize the segmentation of the optic disc of fundus images. The accuracy of the optic disc positioning and segmentation method was calculated based on deep learning of fundus images. Positioning accuracy=T/N, T represented the number of fundus images with correct optic disc positioning, and N represented the total number of fundus images used for positioning. The overlap error was used to compare the difference between the segmentation result of the optic disc and the actual boundary of the optic disc.ResultsOn the dataset from ORIGA, the accuracy of the optic disc localization can reach 99.6%, the average overlap error of optic disc segmentation was 7.1%. The calculation errors of the average cup-to-disk ratio for glaucoma images and normal images were 0.066 and 0.049, respectively. Disc segmentation of each image took an average of 10 ms.ConclusionThe algorithm can locate the disc area quickly and accurately, and can also segment the disc boundary more accurately.

          Release date:2020-09-22 04:09 Export PDF Favorites Scan
        • Study on morphosis parameter of the optic disc of physiologic large cup

          Objective To observe the characteristics of morphosis parameter of the optic disc of physiologic large cup. Methods 100 eyes with physiologic large cup and 74 eyes with normal cup were examined by Heidelberg Retina Tomograph (HRT ). The differences of morphosis parameters between two groups were analyzed comparatively on disc area (DA), cup volume (CV), cup/disc area ratio (C/DR), rim area (RA), cup volume (CV), rim volume (RV), mean cup depth (MeCD), maximum cup depth (MxCD), cup shape measure (CSM), height variation contour (HVC), mean retinal nerve fiber layer thickness (mRNFLt), and retinal nerve fiber layer cross-section area (RNFLcsa). The characteristics of the inferior, superior, nasal, and temporal quadrants of the physiologic large cups were analyzed. Results DA, CA, C/DR, CV, MeCD, CSM (P=0.00, respectively)and MxCD (P=0.04)were significantly larger in eyes with physiologic large cup than in eyes with normal cup. RA, RV, HVC, mRNFLt, RNFLcsa (P=0.00, respectively) were significantly smaller in eyes with physiologic large cup than in eyes with normal cup. The temporal quadrant of RV of the physiologic large cup is the narrowest. RNFLcsa decreased as the fol lowing order: superior, inferior, nasal, and temporal(P<0.05). Conclusions Mo rphosis parameter of the optic discs of physiologic large cup has its own repres entation on characteristics. Compared to normal cups, physiologic large cups had larger discs but smaller mRNFLt. The nasal quadrant of DA was larger than the i nferior quadrant. (Chin J Ocul Fundus Dis,2008,24:213-216)

          Release date:2016-09-02 05:46 Export PDF Favorites Scan
        • The changes in optic disc parameters and thickness of circumpapillary retinal nerve fiber layer in acute uveitis of Vogt-Koyanagi-Harada syndrome with different degrees of optic disc edema

          Objective To compare the differences of optic disc parameters and the thickness of circumpapillary retinal nerve fiber layer (CP-RNFL) in acute uveitis Vogt-Koyanagi-Harada (VKH) syndrome with different degrees of optic disc edema. Methods This is a retrospective study including 40 eyes of 23 VKH patients. The eyes were divided into 2 groups according to the results of fluorescein fundus angiography (FFA). The discs with hyperfluorescence but no leakage were in mild optic disc edema group (group A, 13 patients and 25 eyes), and the discs with hyperfluorescence and leakage were in severe optic disc edema group (group B, 10 patients and 15 eyes). The patients were significantly older in group B than in group A (t=?2.17, P<0.05). The differences of gender, diseased time (t=?1.67) and corrected visual acuity (t=?0.76) between 2 groups were not significant (P>0.05). Eighty eyes of 46 normal healthy subjects, matching group A and group B with age and gender, were divided into group C (26 subjects and 50 eyes) and group D (20 subjects and 30 eyes) respectively. All subjects underwent three dimensional optical coherence tomography examinations. The parameters included average thickness of entire circumpapillary retinal nerve fiber layer (CP-RNFL), thickness of nasal, superior, temporal and inferior quadrant of CP-RNFL, disc area, disc cup area, rim area, cup/disc (C/D) area ratio, C/D horizontal diameter ratio and C/D vertical diameter ratio. Results The disc area, disc cup area and rim area were bigger, the thickness of mean CP-RNFL and the nasal and temporal quadrants of CP-RNFL were thicker in group A than those in group C (P<0.05). The disc area and rim area were bigger, the thickness of mean CP-RNFL and the nasal, superior, temporal and inferior quadrant of CP-RNFL were thicker, C/D area ratio and C/D diameter ratio were smaller in group B than those in group D (P<0.05). The disc area was bigger, disc cup area, C/D area ratio and C/D diameter ratio were smaller, the thickness of mean CP-RNFL and the nasal , superior and inferior quadrants of CP-RNFL were thicker in group B than those in group A (P<0.05). Conclusions Acute VKH uveitis with mild optic disc edema has thicker CP-RNFL in the nasal and temporal quadrants; with severe optic disc edema has thicker CP-RNFL in all 4 quadrants. Acute VKH uveitis also has smaller C/D area ratio and C/D diameter ratio.

          Release date:2017-09-19 03:09 Export PDF Favorites Scan
        • Choroidal thickness of macular and peripapillary area in malignant glaucoma

          ObjectiveTo compare the choroidal thickness (CT) of macular and peripapillary area among malignant glaucoma(MG), chronic primary angle-closure glaucoma (CPACG) and normal control eyes. And to investigate the correlation between CT and MG. Methods Sixteen subjects (32 eyes) with MG, 31 (31 eyes) with CPACG and 32 (32 eyes) normal controls were collected. MG eyes and the fellow non-MG eyes were included in the MG group. CT of all subjects was measured in the fovea, 1mm and 3mm to the fovea and peripapillary area using enhanced-depth imaging technique of optical coherence tomography (OCT-EDI). The average of CT in fovea by horizontal and vertical macular scan was defined as the average CT in fovea. The average of temporal, superior, nasal and inferior CT in 1 mm and 3 mm to the fovea were measured respectively. The average of temporal, superior, nasal and inferior CT was defined as the average CT in peripapillary area. The differences of CT among MG, CPACG and normal controls were compared. And the differences of CT between MG eyes and the fellow non-MG eyes were compared. ResultsAfter eliminating the influence of age, the average CT of MG in the fovea, 1mm and 3mm to the fovea was significantly thicker than that of CPACG and normal controls (P < 0.05). And the average CT of CPACG in the fovea, 1mm and 3mm to the fovea was significantly thicker than that of normal controls (P < 0.05). In peripapillary area, the temporal, superior and inferior CT of MG was significantly thicker than that of CPACG and normal controls (P < 0.05). There was no significant difference of CT in peripapillary area between CPACG and normal controls (P > 0.05). In the fovea, 1mm and 3mm to the fovea and peripapillary area, there was no significant difference of CT between MG eye and the fellow non-MG eye in MG group (t=-1.029~-0.130, P > 0.05). ConclusionsThe choroid thickness of macular and peripapillary area in MG eyes is thicker than that of CPACG and the normal controls. An increased CT of macular and peripapillary area may be one of the risk factors for MG.

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        • Laser photocoagulation or endolaser combined with vitrectomy for congenital optic disc pit maculopathy: “dam sign” of optical coherence tomography is a sign to indicate the anatomic success

          ObjectiveTo investigate the successful signs of laser photocoagulation or endolaser combined vitrectomy for congenital optic disc pit (ODP) with serous macular detachment.MethodsA retrospective case analysis. Twelve eyes of 12 patients with congenital ODP complicated with serous macular detachment diagnosed in Zhongshan Ophthalmic Center from 2003 to 2018 were included in this study. There were 2 males (2 eyes) and 8 females (8 eyes). The average age was 30.17 years old. Retinal laser photocoagulation and/or vitrectomy were performed in all the eyes. The optic disc and macular area were scanned using the tracking mode of the Germany Heidelberg Spectralis OCT instrument. The " dam-sign” change was a retinal choroidal scar on the channel between the ODP and the macula on the OCT image after treatment. The eyes were divided into a " dam-sign” change group (group A, 10 eyes) and no " dam-sign” change group (group B, 2 eyes). The BCVA of eyes in group A was 0.03-0.6. In group A, 1 eye was treated with laser photocoagulation alone, 9 eyes were treated with vitrectomy combined with laser photocoagulation. The BCVA of eyes in group B was 0.1. All the eyes in group B underwent vitrectomy combined with laser photocoagulation. The follow-up was ranged from 6 to 174 months. The same equipment and method before treatment were used for 1, 3, 6, 12, 18, and 24 months after treatment. The BCVA, absorption of subretinal fluid (SRF) and the formation of " dam-sign” change were observed.ResultsAt the last follow-up, the BCVA of eyes in group A was 0.4-1.0 (0.4 in 1 eye, 0.5 in 3 eyes, 0.6 in 2 eyes, 0.8 in 3 eyes, 1.0 in 1 eye). In 9 eyes treated with vitrectomy combined with laser photocoagulation, SRF was completely absorbed. In 1 eye treated with laser photocoagulation alone, SRF remained in small amount. The BCVA of the two eyes in group B was 0.03 and 0.3, respectively; and SRF was not absorbed in both of them.ConclusionsThe " dam-sign” change near optic disc after laser photocoagulation can promote SRF absorption and improve BCVA. It can be used as a success indicator after treatment.

          Release date:2020-01-11 10:26 Export PDF Favorites Scan
        • Observation on the structural characteristics of optic discs in high myopia combined with primary open-angle glaucoma

          ObjectiveTo observe and analyze the structural characteristics of the optic discs in high myopia (HM) combined with primary open-angle glaucoma (POAG) and the optic disc parameters with diagnostic efficacy. MethodsA cross-sectional study. From August 2020 to March 2021, a total of 114 eyes of 68 patients with POAG, HM and healthy volunteers who were diagnosed by Department of Ophthalmology, The First Affiliated Hospital of Kunming Medical University were included in the study. Among them, 21 POAG patients (39 eyes) were divided into H+P group (9 patients, 18 eyes) and non-H+P group (12 patients, 21 eyes) according to whether or not HM was combined; 26 HM patients (37 eyes) were selected as HM group; 21 healthy volunteers (38 eyes) were selected as normal control group. The subjects included 31 males (51 eyes) and 37 females (63 eyes), whose average age was 36.93±12.60 years old. Diopter, central corneal thickness (CCT) and axial length (AL) were measured. There was no significant difference in age (F=8.333), sex composition ratio (χ2=0.863), and CCT (F=1.425) among the four groups (P>0.05); while, there were significant differences in AL (F=69.956), diopter (F=37.711), visual field index (VFI) (F=43.254) and mean defect (MD) (F=49.793) among the four groups (P<0.01). Enhanced depth imaging using optical coherence tomography was used to obtain the tilt parameters, the disc rim parameters, the lamina cribrosa parameters and the retinal nerve fiber layer (RNFL) thickness. The tilt parameters included optic disc horizontal diameter, optic disc vertical diameter, optic disc ellipse index (horizontal diameter/vertical diameter); the disc rim parameters included Bruch’s membrane opening-minimal rim width (BMO), optic cup area, optic disc area, disc rim area, cup-disc area ratio; the lamina cribrosa parameters included anterior laminar insertion depth (ALID), prelaminar neural tissue (PLNT), and lamina cribrosa thickness. The pairwise comparison between groups were performed by ANOVA test. Pearson correlation analysis was used to analyze the correlation between disc tilt parameters, disc rim parameters, lamina cribrosa parameters and visual field parameters, as well as between disc rim parameters and RNFL thickness. According to receiver operating characteristic (ROC) curve and area under the curve (AUC), the predictive value of those above related factors for HM combined with POAG was evaluated. ResultsTilt parameters: compared with the optic disc horizontal diameter of non-H+P group, those of normal control group, HM group and H+P group were significantly decreased (P<0.05), the ellipse indices of HM group and H+P group were significantly lower than those of normal control group and non-H+P group (P<0.05). The results of correlation analysis showed that the optic disc horizontal and vertical diameters were negatively correlated with MD (r=-0.302, -0.235; P=0.002, 0.017), and negatively correlated with VFI (r=-0.291, -0.246; P=0.003, 0.013). Disc rim parameters: the disc cup area and cup-disc area ratio of non-H+P group and H+P group were significantly larger than those of normal control group and HM group (P<0.05). The disc rim area and the average BMO of HM group, non-H+P group and H+P group were significantly smaller than those of normal control group (P<0.05). The results of correlation analysis showed that the cup-disc area ratio (r=-0.584), the average BMO (r=0.650) had the highest correlation with the average RNFL thickness (P<0.001). The superior, inferior, nasal and temporal BMO were all positively correlated with the corresponding quadrant RNFL thicknesses (r=0.431, 0.656, 0.362, 0.375; P<0.05); the optic disc rim area, the average BMO were positively correlated with MD (r=0.449, 0.618) and VFI (r=0.449, 0.605) (P<0.05), among which the correlation of the average BMO was the highest; the optic cup area and cup-disc area ratio were negatively correlated with MD (r=-0.346,-0.559) and VFI (r=-0.312,-0.548) (P<0.001), among which the correlation of the cup-disc area ratio was the highest. Lamina cribrosa parameters: ALID of non-H+P group and H+P group were significantly deeper than those of normal control group and HM group (P<0.05). LC of non-H+P group and H+P group were significantly thinner than those of normal control group and HM group (P<0.05). The results of correlation analysis showed that ALID was negatively correlated with MD and VFI (r=-0.402, P<0.001), VFI (r=-0.405, P=0.001); LC was positively correlated with MD and VFI (r=0.403, P<0.001), VFI (r=-0.401, P=0.015). Comparison of diagnostic efficiency between various optic disc parameters: the results of ROC analysis showed that the cup-disc area ratio had the highest diagnostic performance (AUC=0.847, P=0.007), the maximum Youden index was 0.563, the sensitivity and specificity were 0.833 and 0.730, respectively, and the best critical value was 0.340. ConclusionsOptic disc tilt is more pronounced in HM combined with POAG; BMO in each quadrant could objectively reflect the disc rim defect of HM combined with POAG; the thinning and the backward shift of the lamina cribrosa were consistent with the aggravation of the visual field defect. Among them, the cup-disc area ratio had better diagnostic performance.

          Release date:2022-07-18 03:05 Export PDF Favorites Scan
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