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        find Keyword "Optical coherence tomography" 71 results
        • Advances in application of optical coherence tomography angiography for quantitative analysis in central serous chorioretinopathy

          Central serous chorioretinopathy (CSC) is one of the representative pachychoroid spectrum disease. Although fundus fluorescein angiography and indocyanine green angiography can be used as the gold standard for the diagnosis of CSC, they are invasive examinations, which may bring certain risks in clinical application and cannot help us obtain quantitative parameters. Optical coherence tomography angiography (OCTA), as a non-invasive and quantitative examination, is an important imaging tool for understanding the pathogenesis, diagnosis and treatment of CSC. With the advancement of OCTA, the swept-source OCTA has a satisfying scanning depth, a wider scanning range and a higher resolution. The development of OCTA broadens the horizons of the pathogenesis of CSC, promotes the understanding of the pathophysiology of CSC, and sheds new light for its clinical diagnosis and treatment. Based on OCTA, the choroid and retina in eyes with CSC are presented with qualitative and quantitative changes in vascular system. OCTA-guided CSC treatment and the discovery of prognostic markers based on OCTA challenge the application of traditional imaging techniques in CSC. With the continuous improvement and progress of OCTA technology, traditional angiography combined with OCTA will bring great benefits to the diagnosis and treatment of CSC. This review summarizes the quantitative application of OCTA in the pathogenesis, diagnosis and treatment of CSC.

          Release date:2023-05-18 10:05 Export PDF Favorites Scan
        • Relationship between the thickness of macula and the changes of multifocal electroretinograms in diabetic retinopathy

          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)

          Release date:2016-09-02 06:03 Export PDF Favorites Scan
        • Research on attention-enhanced networks for subtype classification of age-related macular degeneration in optical coherence tomography

          Subtype classification of age-related macular degeneration (AMD) based on optical coherence tomography (OCT) images serves as an effective auxiliary tool for clinicians in diagnosing disease progression and formulating treatment plans. To improve the classification accuracy of AMD subtypes, this study proposes a keypoint-based, attention-enhanced residual network (KPA-ResNet). The proposed architecture adopts a 50-layer residual network (ResNet-50) as the backbone, preceded by a keypoint localization module based on heatmap regression to outline critical lesion regions. A two-dimensional relative self-attention mechanism is incorporated into convolutional layers to enhance the representation of key lesion areas. Furthermore, the network depth is appropriately increased and an improved residual module, ConvNeXt, is introduced to enable comprehensive extraction of high-dimensional features and enrich the detail of lesion boundary contours, ultimately achieving higher classification accuracy of AMD subtypes. Experimental results demonstrate that KPA-ResNet achieves significant improvements in overall classification accuracy compared with conventional convolutional neural networks. Specifically, for the wet AMD subtypes, the classification accuracies for inactive choroidal neovascularization (CNV) and active CNV reach 92.8% and 95.2%, respectively, representing substantial improvement over ResNet-50. These findings validate the superior performance of KPA-ResNet in AMD subtype classification tasks. This work provides a high-accuracy, generalizable network architecture for OCT-based AMD subtype classification and offers new insights into integrating attention mechanisms with convolutional neural networks in ophthalmic image analysis.

          Release date:2025-10-21 03:48 Export PDF Favorites Scan
        • Imaging features of pathological myopic perivascular abnormalities and macular retinoschisis and their correlation with clinical features

          Objective To observe and analyze the imaging features of pathologic myopic paravascular abnormalities (PVA) and macular retinoschisis (MRS) and their relationship with clinical features. MethodsA retrospective case series study. A total of 371 eyes of 224 patients with pathological myopia with PVA and/or MRS diagnosed by examination in Department of Ophthalmology of the First Affiliated Hospital of Zhengzhou University from September 2021 to December 2023 were included in the study. There were 74 eyes in 48 males and 297 eyes in 176 females. Age were 54 (49, 61) years; equivalent spherical lens (SE) was ?13.375 (?18.00, ?10.00) D. Axial length (AL) was 29.84 (28.27, 31.24) mm. According to the features of ultra-wide-angle sweep source optical coherence tomography, PVA morphology was divided into blood vessels and paravascular microfolds, paravascular retinal cysts, paravascular retinal splits and paravascular lamellar macular holes. MRS was divided into inner layer, outer layer and mixed layer according to splitting level, and grouped accordingly. The presence of dome-shaped macula (DSM), internal and external lamellar macular hole, and full lamellar macular hole (FTMH) were recorded. According to whether PVA combined with MRS or not, the affected eyes were divided into PVA group and PVA combined with MRS group. According to whether MRS involved the fovea, the affected eyes were divided into two groups: MRS not involved the fovea group and MRS involved the fovea group. Mann-Whitney U test was used to compare age, SE and AL among different groups. Qualitative data were compared by χ2 test. ResultsIn 371 eyes, there were 120 eyes in the simple PVA group; in the MRS group, there were 251 eyes, of which 208 eyes were in the PVA combined with MRS group. There were 33, 27, 3, 14, 12, 56, 28, and 7 eyes with or without retinal detachment, choroidal neovascularization, DSM, preretinal membrane, and simple superficial detachment of neuroepithelium in inner lamina, outer lamina, and FTMH, respectively. In 328 eyes with PVA, blood vessels and paravascular microfolds, paravascular retinal cysts, paravascular retinal splits and paravascular lamellar macular holes were 151, 236, 202 and 72 eyes, respectively. There were 142 eyes with single lesion (43.29%, 142/328). There were 186 eyes with 2 or more lesions (56.71%, 186/328). There were 34 eyes in the inner MRS group, 92 eyes in the outer MRS group and 125 eyes in the mixed MRS group, respectively. It involved 155 eyes in the fovea group; 96 eyes in the fovea group were not involved. There were significant differences in the number of PVA eyes between the outer MRS group, the inner MRS group and the mixed MRS group (χ2=30.614, 28.379; P<0.001). Compared with PVA group, PVA group combined with MRS group was more likely to have two or more PVA lesions, the difference was statistically significant (χ2=30.535, P<0.001). Compared with the inner MRS group and mixed MRS group, the age of the simple PVA group was younger, and the age of the outer MRS group was older, and the differences were statistically significant (P<0.05). Compared with the inner MRS group and the outer MRS group, the simple PVA group had short AL, less myopia and better optimal corrected visual acuity (BCVA), while the mixed MRS group had long AL, more myopia and worse BCVA, and the differences were statistically significant (P<0.05). Compared with the PVA group and the inner MRS group, the fovea was more involved in the outer MRS group and the mixed MRS group, and the difference was statistically significant (χ2=3.906, 10.836; P<0.05). Those with MRS involved in fovea were older, AL was longer, myopia was more severe, and BCVA was worse (P<0.001). DSM-associated splits were less likely to involve macula (P<0.001). ConclusionPVA and MRS exhibit a variety of presentations, and their imaging features correlate with clinical features.

          Release date:2025-02-25 09:39 Export PDF Favorites Scan
        • Optical coherence tomography of the macular lesion in patients with central retinal veinocclusion

          Objective To observe the morphologic characters of macular lesions in patients with central retinal vein occlusion(CRVO) in optical coherence tomography(OCT). Methods Thirty-eight patients with the clinical diagnosis of CRVO were examined by OCT.Four scan lines traversing the fovea with the same length and the same angle gap were performed as the basic scan in every eye.Additional scan were selected according to individuals including changing the length or angle of the scan lines and selecting different diameter circle pattern scan. Results Cystoid macular edema (CME) was found in 15 eyes,detachment of the neurosensory retina in 6 eyes,thickened neurosesory retina in 11 eyes,slight intraretinal fluid in 4 eyes,and markedly thichened neurosensory retina in 2 eyes with secondary premacular membrane and intraretinal fluid. Conclusions The major OCT morphologic characters of macular lesions in patinets with CRVO may include:cystoid macular edema,detachment of neurosensory retina,and secondary premacular membrane and pigmentary epithelial changes.These would be helpful for diagnosing and evaluating macular lesion in CRVO. (Chin J Ocul Fundus Dis, 1999, 15: 201-204)

          Release date:2016-09-02 06:07 Export PDF Favorites Scan
        • Clinical characteristics and features of images of optical coherence tomography in vitreomacular traction syndrome

          ObjectiveTo observe the characteristics of the images of optical coherence tomography (OCT) performed on the patients with vitreomacular traction syndrome and its clinical significance.MethodsThe clinical data of 25 patients with vitreomacular traction syndrome diagnosed by OCT, fundus fluorescein angiography, and B-scan ultrasonography and confirmed by surgical treatment were retrospectively analyzed. The features of images of OCT in vitreomacular traction syndrome were observed.ResultsFive types were found in the images of OCT in the patients with vetreomacular traction syndrome. The main characteristic of the images of OCT in the patients with vitreomacular traction was the highly reflective band of the vitreous posterior cortex inservion at fovea. In 25 patients, vitreomacular traction associated with macular edema was found in 10, macular hole in 3, macular epiretinal membrane in 6, retinoschisis in 1, and retinal detachment in 5.ConclusionOCT is a potential powerful toll for detecting and monitoring vitreomacular traction syndrome. (Chin J Ocul Fundus Dis, 2005,21:86-89)

          Release date:2016-09-02 05:52 Export PDF Favorites Scan
        • Optical coherence tomography features of central exudative chorioretinopathy

          Objective lt;brgt;To investigate the morphological features of choroidal neovascularization (CNV) in central exudative chorioretinopathy (CEC) using optical coherence tomography(OCT). lt;brgt; lt;brgt;Methods lt;brgt;OCT and fundus fluorescein angiography (FFA) were performed in 41 cases (43 eyes) of CEC,and the course of CEC disease was from 1 week to 10 months. Twenty-seven of 43 eyes were also examined by indocyanine green angiography (ICGA). lt;brgt; lt;brgt;Results lt;brgt;OCT images revealed 5 kinds of morphological features of CEC: well-defined CNV(41.86 %),poorly-defined CNV(30.23 %),hemorrhagic pigment epithelium detachment (PED)(16.28 %), CNV companied with serous (6.98 %) or hemorrhagic neurosensory retina detachment (4.65 %). CNV mainly showed well-defined and poorly-defined CNV (72.09 %).In those eyes that could clear define the CNV boundary,there were 12 eyes on FFA examination and 20 eyes on ICGA examination which defined the boundary from retinal horizontal plane, while there were 23 eyes on OCT examination which defined the boundary from retinal vertical section. Classic CNV on FFA consistently presented with well-defined boundaries on OCT, whereas non-classic CNV had a variable cross-sectional appearance. lt;brgt; lt;brgt;Conclusions lt;brgt;The OCT morphological features of CNV in CEC is mainly well-defined CNV and poorly-defined CNV; OCT examination can precisely observe the retinal and choriocapillaries pathological anatomy of CEC from retinal vertical section, in making the CEC diagnosis as an important complementary examination of FFA and ICGA which observe the focus from retinal horizontal plane. lt;brgt; lt;brgt;(Chin J Ocul Fundus Dis, 2002, 18: 121-124)

          Release date:2016-09-02 06:01 Export PDF Favorites Scan
        • 病理性近視黃斑部脈絡膜新生血管光動力療法治療后光相干斷層掃描觀察結果分析

          Release date:2016-09-02 05:48 Export PDF Favorites Scan
        • Morphological characteristics and correlation of dome-shaped macula with macula hole in high myopia

          ObjectiveTo observe the morphological characteristics of dome-shaped macula (DSM) and macular hole (MH) in high myopia by optical coherence tomography (OCT), to further explore the correlation between DSM and MH. MethodsA retrospective case-control study. From April 2021 to December 2023, 963 eyes of 503 patients with high myopia (myopic diopter ≥6.00 D) in Department of Ophthalmology of the Fourth Hospital of Hebei Medical University were enrolled in the study. The age of patients ranged from 5 to 89 years old, with the mean age of (48.91±16.69) years. Diopter was ?6.00 to ?26.00 (?10.49±3.15) D. All eyes were examined by OCT. The width and height of DSM, subfoveal choroidal thickness (SFCT), inner port diameter and base diameter of MH were measured by software on OCT. According to the OCT image features, DSM was divided into horizontal and vertical oval-shaped DSM, and symmetrical round DSM. According to the presence or absence of DSM, the eyes were divided into DSM group and non-DSM group. Then, the affected eyes with MH were divided into DSM with MH group and non-DSM with MH group. The incidence of DSM, the incidence of MH in the DSM group and the non-DSM group, the inner port diameter of MH, the base diameter of MH, SFCT, and the location of retinoschisis (RS) in the DSM with MH group and the non-DSM with MH group were observed. Independent sample t test or non-parametric Mann-Whitney U test was used for comparison between groups. Pearson correlation analysis was used to analyze the related factors of MH inner port diameter, base diameter and DSM width, height, height/width ratio. ResultsAmong the 963 eyes, the DSM group and the non-DSM group were 266 (27.6%, 266/963) and 697 (72.4%, 697/963) eyes. Compared with the non-DSM group, patients in the DSM group were older (Z=?11.302), had higher degree of myopia (Z=?8.944), thinner SFCT (Z=?16.244), and higher incidence of MH (χ2=8.828), and the differences were statistically significant (P<0.05). Compared with non-DSM with MH group, the patients in DSM with MH group were older (t=2.610), higher myopia diopter (t=3.593), and thinner SFCT (t=3.505), the differences were statistically significant (P<0.05). There was no significant difference in the number of eyes in the epiretinal membrane between the two groups (χ2=0.119, P=0.730). In the DSM with MH group, RS mostly occurred in the outer retina with a large range, while in the non-DSM with MH group, RS mostly occurred in the outer and inner retina with a small range. There was a statistically significant difference in the number of eyes at different positions of RS between the two groups (χ2=25.131, P<0.05). The results of correlation analysis showed that there was no correlation between the inner port and base diameter of MH and the width, height, height/width ratio of DSM (P>0.05). ConclusionsCompared with high myopia patients without DSM, patients with DSM are older, have more severe myopia and thinner SFCT. In DSM patients with MH, RS often occurs in the outer retina and has a large range. There was no significant association between DSM morphology and MH size.

          Release date:2025-02-25 09:39 Export PDF Favorites Scan
        • Preliminary observation of the effect of cystic cavity on visual function of macular area before and after operation in idiopathic macular hole

          ObjectiveTo observe and analyze the effect of peripore cavity size on visual function of macular area before and after surgery for idiopathic macular hole (IMH). MethodsA retrospective clinical study. From July 2020 to February 2021, a total of 25 patients with 25 eyes with monocular IMH (operation group) diagnosed by ophthalmology examination in Department of ophthalmology, Fourth Hospital of Hebei Medical University were included in the study. The control group was contralateral healthy eyes. All subjects were examined by best corrected visual acuity (BCVA), microfield of vision, frequency domain optical coherence tomography (SD-OCT), and OCT angiography (OCTA). The diameter of macular hole was measured by SD-OCT. The cystic morphology of deep capillary plexus (DCP) was detected by en face OCT, and the cystic area was measured by Image J software. MP-3 microperimeter was used to measure central macular retinal light sensitivity (MS) and mean macular retinal light sensitivity (MMS). Central macular retinal light sensitivity (CMS), MMS and cystic cavity MS were measured in the operation group. MMS was measured in the control group. The microperimetry images were superimposed on the DCP layer of OCTA to identify and calculate the average MS within the lumen and compare it with the control group. Standard three incisions were performed in all affected eyes by vitrectomy of the flat part of the ciliary body + stripping of the inner boundary membrane + intraocular sterile air filling. Three months after the operation, the same equipment and methods were used to perform relevant examinations. Paired sample t test was used to compare MS between operation group and control group. Pearson correlation analysis was used to analyze the correlation between capsular area, macular hole diameter before and after operation and MS before and after operation. The correlation between BCVA and capsular area before and after surgery was analyzed by Spearman correlation analysis. ResultsIn the surgical group, the retinal MS was (4.24±3.07) dB. The MMS of control group was (19.08±6.11) dB. The MS in the surgical group was significantly lower than that in the control group, and the difference was statistically significant (t=10.832, P<0.01). Before operation, the area of cyst was (1.04±0.55) mm2, and the diameter of macular hole was (564.80±166.59) μm. CMS and MMS were (2.27±2.29) dB and (9.08±3.65) dB, respectively. The diameter of macular hole (r=0.50, P=0.010) and BCVA before operation (r=0.57, P<0.001) were positively correlated with peripore cavity area. Before operation, CMS and MMS were negatively correlated with peripore cavity area (r=-0.53, -0.47; P=0.010, 0.020). At 3 months after surgery, the capsular area was negatively correlated with CMS and MMS (r=-0.65,-0.76; P=0.020, 0.030). There was no correlation with BCVA (r=0.23, P=0.470). ConclusionsRetinal MS is decreased in the peri-capsular area of IMH pore. There is a positive correlation between capsule area, BCVA and macular hole diameter before operation. The capsular area is negatively correlated with CMS and MMS before operation.

          Release date:2023-12-27 08:53 Export PDF Favorites Scan
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