In this work,we aim to introduce some modifications to the Anam-Net deep neural network(DNN)model for segmenting optic cup(OC)and optic disc(OD)in retinal fundus images to estimate the cup-to-disc ratio(CDR).The CDR i...In this work,we aim to introduce some modifications to the Anam-Net deep neural network(DNN)model for segmenting optic cup(OC)and optic disc(OD)in retinal fundus images to estimate the cup-to-disc ratio(CDR).The CDR is a reliable measure for the early diagnosis of Glaucoma.In this study,we developed a lightweight DNN model for OC and OD segmentation in retinal fundus images.Our DNN model is based on modifications to Anam-Net,incorporating an anamorphic depth embedding block.To reduce computational complexity,we employ a fixed filter size for all convolution layers in the encoder and decoder stages as the network deepens.This modification significantly reduces the number of trainable parameters,making the model lightweight and suitable for resource-constrained applications.We evaluate the performance of the developed model using two publicly available retinal image databases,namely RIM-ONE and Drishti-GS.The results demonstrate promising OC segmentation performance across most standard evaluation metrics while achieving analogous results for OD segmentation.We used two retinal fundus image databases named RIM-ONE and Drishti-GS that contained 159 images and 101 retinal images,respectively.For OD segmentation using the RIM-ONE we obtain an f1-score(F1),Jaccard coefficient(JC),and overlapping error(OE)of 0.950,0.9219,and 0.0781,respectively.Similarly,for OC segmentation using the same databases,we achieve scores of 0.8481(F1),0.7428(JC),and 0.2572(OE).Based on these experimental results and the significantly lower number of trainable parameters,we conclude that the developed model is highly suitable for the early diagnosis of glaucoma by accurately estimating the CDR.展开更多
Glaucoma as an irreversible blinding opioid neuropathy disease, its blindness rate is the second only after cataract in the world. The optic cup-to-disc ratio(CDR) is generally considered to be an important clinical i...Glaucoma as an irreversible blinding opioid neuropathy disease, its blindness rate is the second only after cataract in the world. The optic cup-to-disc ratio(CDR) is generally considered to be an important clinical indicator for judging the severity of glaucoma by ophthalmologists from retinal fundus image. In this letter, we propose an automatic CDR measurement method that consists of a novel optic disc localization method and a simultaneous optic disc and cup segmentation network based on the improved U shape deep convolutional neural network. Experimental results demonstrate that the proposed method can achieve superior performance when compared with other existing methods. Thus, our method can be used as a powerful tool for glaucoma-assisted diagnosis.展开更多
Glaucoma is an eye disease that usually occurs with the increased Intra-Ocular Pressure(IOP),which damages the vision of eyes.So,detecting and classifying Glaucoma is an important and demanding task in recent days.For...Glaucoma is an eye disease that usually occurs with the increased Intra-Ocular Pressure(IOP),which damages the vision of eyes.So,detecting and classifying Glaucoma is an important and demanding task in recent days.For this purpose,some of the clustering and segmentation techniques are proposed in the existing works.But,it has some drawbacks that include ineficient,inaccurate and estimates only the affected area.In order to solve these issues,a Neighboring Differential Clustering(NDC)-Intensity V ariation Making(IVM)are proposed in this paper.The main intention of this work is to extract and diagnose the abnormal retinal image by identifying the optic disc.This work includes three stages such as,preprocessing,clustering and segmentation.At first,the given retinal image is preprocessed by using the Gaussian Mask Updated(GMU)model for eliminating the noise and improving the quality of the image.Then,the cluster is formed by extracting the threshold and patterns with the help of NDC technique.In the segmentation stage,the weight is calculated for pixel matching and ROI extraction by using the proposed IVM method.Here,the novelty is presented in the clustering and segmentation processes by developing NDC and IVM algorithms for accurate Glaucoma identification.In experiments,the results of both existing and proposed techniques are evaluated in terms of sensitivity,specificity,accuracy,Hausdorff distance,Jaccard and dice metrics.展开更多
AIM:To compare the cup-to-disc ratio(CDR)and optic disc morphology between eyes with congenital cataract and eyes without cataract in children under 3 years old.METHODS:This study included 63 patients with bilateral c...AIM:To compare the cup-to-disc ratio(CDR)and optic disc morphology between eyes with congenital cataract and eyes without cataract in children under 3 years old.METHODS:This study included 63 patients with bilateral congenital cataract(mean age of 55.72±46.50wk,44 were male),33 patients with unilateral cataract(mean age of 56.63±33.23wk,16 were male),and 31 age-matched healthy children(mean age of 55.80±29.29wk,17 were male).Fundus photographs were taken with the RetCam 3 system.The horizontal-to-vertical disc diameter ratio(HVDR)was used as an index to describe the oval form of the optic disc.RESULTS:The horizontal cup-to-disc ratio(HCDR),vertical cup-to-disc ratio(VCDR)and HVDR of cataract eyes in unilateral groups were significantly smaller than those of the normal eyes(P<0.05).In the unilateral group,the HCDR,VCDR and HVDR of cataract eyes were significantly smaller than those in fellow eyes(P<0.05).The HVDR of eyes in the bilateral group was significantly smaller than those in the age-matched normal eyes(P<0.001).The form of optic disc of the cataract eyes in both the bilateral and unilateral groups was more vertical-oral than the normal eyes in the unilateral and the age-matched groups(P<0.05).CONCLUSION:Our results show that eyes with congenital cataract has a smaller HVDR and the form of the optic disc tended to be vertical-oval in young children.展开更多
AIM:To explore the impact of insulin-like growth factor-1 receptorα(IGF-1Rα)on the differentiation fate of optic-cupderived retinal stem cells(OC-RSCs)into retinal ganglion cells(RGCs)in vitro.METHODS:OC-RSCs were i...AIM:To explore the impact of insulin-like growth factor-1 receptorα(IGF-1Rα)on the differentiation fate of optic-cupderived retinal stem cells(OC-RSCs)into retinal ganglion cells(RGCs)in vitro.METHODS:OC-RSCs were isolated from optic cups of rats on embryonic day 12.5,and high-purity OC-RSCs were obtained by conditioned culture and passage.Differentiation of OC-RSCs into RGCs under different serum concentrations was examined using flow cytometry,and the serum concentration with high interference with differentiation ratio was selected.Furthermore,the effect of blocking IGF-1Rαon the differentiation of OC-RSCs into RGCs was analyzed through immunocytochemistry and Western blotting.RESULTS:Immunohistochemical analysis revealed IGF-1Rαwas highly expressed in rat embryos at day 12.5.OC-RSCs were isolated and purified,and high-purity OCRSCs were obtained.When 2.5%serum was administered,the ratio of differentiated RGCs(Thy-1.1 positive)decreased significantly,and the results of immunoblotting also confirmed the blockade of IGF-1Rαreduced Thy-1.1 protein expression.CONCLUSION:IGF-1Rαblocking can reduce the differentiation of OC-RSCs into RGCs.展开更多
Myopia,a worldwide condition,is a multifactorial disease resulting in many ocular complications.Early onset of myopia has a great tendency to develop high myopia and pathological myopia later in life.The pathophysiolo...Myopia,a worldwide condition,is a multifactorial disease resulting in many ocular complications.Early onset of myopia has a great tendency to develop high myopia and pathological myopia later in life.The pathophysiology and progression of myopia is still unclear.Owing to its involving in visual function,optic disc and peripapillary change in high myopia can＇t be neglected,and it may help in better understanding of the pathophysiology or mechanism of myopia progression.Recently,advanced imaging techniques have been developed,such as optical coherence tomography（OCT）,allowing for better detecting of optic disc and peripapillary change.OCT is a highresolution and noninvasive measurement for detection of ocular structure.Herein,we provide an updated review of optic disc and peripapillary change in OCT image,including its characteristics and clinical significance.We also propose some problems needed further investigation.展开更多
AIM:To explore changes in the optic disc and peripapillary atrophy(PPA)in school-age children with ametropia using color fundus photography combined with artificial intelligence(AI)technology.METHODS:Based on the retr...AIM:To explore changes in the optic disc and peripapillary atrophy(PPA)in school-age children with ametropia using color fundus photography combined with artificial intelligence(AI)technology.METHODS:Based on the retrospective case-controlled study,226 eyes of 113 children aged aged 6–12y were enrolled from October 2021 to May 2022.According to the results of spherical equivalent(SE),the children were divided into four groups:low myopia group(66 eyes),moderate myopia group(60 eyes),high myopia group(50 eyes)and emmetropia control group(50 eyes).All subjects underwent un-aided visual acuity,dilated pupil optometry,best-corrected visual acuity(BCVA),intraocular pressure,ocular axis measurement and color fundus photography.RESULTS:The width of PPA,horizontal diameter ratio of PPA to the optic disc and area ratio of PPA to the optic disc were significantly different among the four groups(P<0.05).The width of the nasal and temporal neuroretinal rim,the roundness of the optic disc,the height of PPA,the vertical diameter ratio of PPA to the optic disc,and the average density of PPA in the high myopia group were significantly different compared with the other three groups(P<0.05).There were strong negative correlations between SE and area ratio of PPA to the optic disc(r=-0.812,P<0.001)and strong positive correlation between axial length(AL)and area ratio of PPA to the optic disc(r=0.736,P<0.001).CONCLUSION:In school-age children with high myopia,the nasal and temporal neuroretinal rims are narrowed and even lost,which have high sensitivity.The area ratio of the PPA to the optic disc could be used as an early predictor of myopia progression,which is of great significance for the development prevention and management of myopia.展开更多
AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control...AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control subjects were enrolled in the study.One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm^(2) rectangular area.Radial peripapillary capillary(RPC)density,peripapillary retinal nerve fiber layer(pRNFL)thickness,cup volume,rim area,disc area,cup-to-disc(c/d)area ratio,and vertical c/d ratio were obtained automatically using device software.Automated parapapillary choroidal microvasculature(PPCMv)density was calculated using MATLAB software.When the vertical c/d ratio of the optic disc was absent or small cup,it was considered as a crowded disc.RESULTS:The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes(P=0.740).There was no difference in pRNFL between the two groups(P=0.102).There were no differences in RPC density in whole image(P=0.826)and peripapillary region(P=0.923),but inside disc RPC density was higher in crowded optic discs(P=0.003).The PPCMv density in the inner-hemisuperior region was also lower in crowded discs(P=0.026).The pRNFL thickness was positively correlated with peripapillary RPC density(r=0.498,P<0.001).The inside disc RPC density was negatively correlated with c/d area ratio(r=-0.341,P=0.002).CONCLUSION:The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs.展开更多
Dear Editor,We present the first reported case of nasal optic disc pit resulting in serous detachment of the macula. Optic disc pit is a rare congenital anomaly occurring in one out of 11 000 people. The appearance is...Dear Editor,We present the first reported case of nasal optic disc pit resulting in serous detachment of the macula. Optic disc pit is a rare congenital anomaly occurring in one out of 11 000 people. The appearance is a localized round or oval depression in that is grey, yellow or black in colour depending on the amount of glial tissue present.展开更多
AIMTo evaluate the possible relationship of optic disc area with retina nerve fiber layer in different glaucoma subtypes.METHODSOne eye each was chosen from 45 patients with ocular hypertension, 45 patients with prima...AIMTo evaluate the possible relationship of optic disc area with retina nerve fiber layer in different glaucoma subtypes.METHODSOne eye each was chosen from 45 patients with ocular hypertension, 45 patients with primary open angle glaucoma, 45 patients with pseudoexfoliation glaucoma and 45 healthy controls followed in our hospital. The records of the patients were reviewed retrospectively. Optic disc area and circumpapillary retina nerve fiber layer measurements were obtained using optical coherence tomography. Central corneal thickness was measured by ultrasound pachymetry.RESULTSThe median disc area in the patients with primary open angle glaucoma was significantly higher than the patients with ocular hypertension (2.19 vs 1.90 mm<sup>2</sup>, P=0.030). The median retina nerve fiber layer was thinner in the patients with primary open angle glaucoma and pseudoexfoliation glaucoma than the patients with ocular hypertension for superior, inferior and temporal quadrants. After adjustment for age, no difference in central corneal thickness was found between the groups. Greater disc area was associated with thicker retinal nerve fiber layer for superior, inferior and nasal quadrants in the patients with primary open angle glaucoma. There was no correlation between disc area and central corneal thickness measurements of the groups.CONCLUSIONDisc size affects the retinal nerve fiber layer thickness in eyes with primary open angle glaucoma and is a possible risk factor for glaucomatous optic nerve damage.展开更多
Glaucoma disease causes irreversible damage to the optical nerve and it has the potential to cause permanent loss of vision.Glaucoma ranks as the second most prevalent cause of permanent blindness.Traditional glaucoma...Glaucoma disease causes irreversible damage to the optical nerve and it has the potential to cause permanent loss of vision.Glaucoma ranks as the second most prevalent cause of permanent blindness.Traditional glaucoma diagnosis requires a highly experienced specialist,costly equipment,and a lengthy wait time.For automatic glaucoma detection,state-of-the-art glaucoma detection methods include a segmentation-based method to calculate the cup-to-disc ratio.Other methods include multi-label segmentation networks and learning-based methods and rely on hand-crafted features.Localizing the optic disc(OD)is one of the key features in retinal images for detecting retinal diseases,especially for glaucoma disease detection.The approach presented in this study is based on deep classifiers for OD segmentation and glaucoma detection.First,the optic disc detection process is based on object detection using a Mask Region-Based Convolutional Neural Network(Mask-RCNN).The OD detection task was validated using the Dice score,intersection over union,and accuracy metrics.The OD region is then fed into the second stage for glaucoma detection.Therefore,considering only the OD area for glaucoma detection will reduce the number of classification artifacts by limiting the assessment to the optic disc area.For this task,VGG-16(Visual Geometry Group),Resnet-18(Residual Network),and Inception-v3 were pre-trained and fine-tuned.We also used the Support Vector Machine Classifier.The feature-based method uses region content features obtained by Histogram of Oriented Gradients(HOG)and Gabor Filters.The final decision is based on weighted fusion.A comparison of the obtained results from all classification approaches is provided.Classification metrics including accuracy and ROC curve are compared for each classification method.The novelty of this research project is the integration of automatic OD detection and glaucoma diagnosis in a global method.Moreover,the fusion-based decision system uses the glaucoma detection result obtained using several convolutional deep neural networks and the support vector machine classifier.These classification methods contribute to producing robust classification results.This method was evaluated using well-known retinal images available for research work and a combined dataset including retinal images with and without pathology.The performance of the models was tested on two public datasets and a combined dataset and was compared to similar research.The research findings show the potential of this methodology in the early detection of glaucoma,which will reduce diagnosis time and increase detection efficiency.The glaucoma assessment achieves about 98%accuracy in the classification rate,which is close to and even higher than that of state-of-the-art methods.The designed detection model may be used in telemedicine,healthcare,and computer-aided diagnosis systems.展开更多
Background: Optic disc oedema has various underlying pathologies, however, unless visually disabling does not usually bring a patient to the physician. The more common symptoms of headache, nausea and vomiting lead to...Background: Optic disc oedema has various underlying pathologies, however, unless visually disabling does not usually bring a patient to the physician. The more common symptoms of headache, nausea and vomiting lead to the incidental detection of bilateral disc oedema [1]. Optic disc oedema seen following spinal surgery is usually associated with visual acuity changes and often goes by the acronym POVL (Peri/ postoperative visual loss) wherein, as the name goes, visual acuity changes are profound [2] [3] [4]. Purpose: We would like to highlight a case of transient Bilateral Optic Disc oedema following Lumbar spinal surgery maintaining normal visual acuity and attaining spontaneous resolution. Case Report: A 42-year-old female presented with transient obscuration of vision and flashes of light post an uneventful lumbar spinal surgery. Ophthalmic evaluation revealed normal visual acuity and pupils but marked disc edema right more significant than left. There was no colour vision deficit, neither any field changes. By a process of exclusion, it was likely the patient had developed bilateral disc oedema secondary to the spinal surgery. On follow-up 6 weeks and 3 months later, the oedema had completely settled and visual acuity remained at 6/6. Conclusion: Optic disc oedema can be unilateral or bilateral with some of the uncommon conditions mentioned secondary to spinal surgery, however, in those situations, visual loss has been severe and permanent. Our case is unusual in its combination of disc edema with normal acuity along with its transient nature and resolution and to our knowledge, has not been published before.展开更多
Purpose:To evaluate the changes of optic disc parameters in primary open angle glaucoma(POAG)patients after surgical and medical treatment,.and analyze the determinants of these changes.Methods:.A total of 67 patients...Purpose:To evaluate the changes of optic disc parameters in primary open angle glaucoma(POAG)patients after surgical and medical treatment,.and analyze the determinants of these changes.Methods:.A total of 67 patients were enrolled in this study.Thirty nine patients.(40 eyes) underwent trabeculectomy and 28 patients(32 eyes).received intra-ocular pressure(IOP) lowering medical therapy..All subjects underwent bilateral routine ocular examination and Heidelberg retina tomography.(HRT) before treatment and 2 weeks,.1 month,3 months,.6 months and 1 year after treatment..Changes in optic disc parameters in both the surgical and medical groups were analyzed,as was the influence of disease severity and IOP reduction on these changes.Results:.In the surgical group,the average preoperative IOP was 32.8±8.64 mmHg,.which showed a significant decline at each post-operative visit..Most optic disc parameters measured by HRT were significantly improved after trabeculectomy.(P=0.001～0.01),.though the amount of improvement declined gradually during the post-operative period.Rim volume (RV),cup shape measure (CSM),mean RNFL (mRNFL),RNFL cross sectional area (RNFLA) and vertical cup-to-disc ratio (C/D) still remained significantly below the pre-operative mean one year after surgery.In the medical group,the mean IOP before treatment was 24.8±4.32 mmHg and remained < 21 mmHg on all subsequent post-treatment visits.However,no significant changes in optic disc parameters were found after initiation of medical treatment(F=0.52～2.21,P=0.75～0.07).In the surgical group,the extent of reduction of IOP was positively correlated with the improvement in RV,CSM and vertical C/D(r=0.41～0.58,P=0.001～0.04) at one year after trabeculectomy.The absolute value of the mean deviation on visual field testing was negatively correlated with the improvement of RV and CSM (r=-0.43～-0.62,P=0.03～0.001).Conclusion:Improvement in optic disc parameters occurred more commonly after surgical than medical treatment in POAG patients.The amount of reduction of IOP was correlated with the extent of this improvement,which may be more limited in more severe glaucoma.展开更多
AIM:To evaluate concordance between the clinical assessment of glaucomatous progression of the optic disc photography and progression identified by Heidelberg Retina Tomograph(HRT)in patients with suspected primary ju...AIM:To evaluate concordance between the clinical assessment of glaucomatous progression of the optic disc photography and progression identified by Heidelberg Retina Tomograph(HRT)in patients with suspected primary juvenile open angle glaucoma(JOAG).METHODS:Optic disc photographs and corresponding HRTⅡseries were reviewed.Optic disc changes between first and final photographs were noted as well as progression identified by HRT topographic change analysis(TCA)and rim area regression line(RARL)Agreement between progression indentified by photography and HRT methods was assessed.Progression,determined from optic disc photographs by consensus assessment was used as the reference standard.RESULTS:A total of 31 patients(59 eyes)with suspected JOAG were studied.Agreement for progression/no progression between TCA and photography was obtained in 4 progressing eyes and 38stable eyes(71.19%,k=0.11).Agreement for progression/no progression between RARL and photography was detected in 5 progressing eyes and in 34 stable eyes(66.10%,k=0.15).The number of HRT per patient was statistically higher in the progressing group(P=0.034).CONCLUSION:Agreement for detection of longitudinal changes between photography and HRT analysis was poor.One way to improve the chance of discovery of the progression could be increasing the number of HRT examinations.展开更多
Purpose: The aim of this study is early detection of increased cup to disc ratio and a survey study of cup-disc ratio in Egyptian children age group less than 15 years. Methods: Three hundred and eighty-two (382) chil...Purpose: The aim of this study is early detection of increased cup to disc ratio and a survey study of cup-disc ratio in Egyptian children age group less than 15 years. Methods: Three hundred and eighty-two (382) children were enrolled in this study. They were classified into three age groups;infants’ Group (1) from 0-2 years, preschool Group (2) from 2-6 years and school children Group (3) from 6-15 years old. C/D ratio was measured for each child. Results: In Group (1), normal C/D ratio ranged from 0 to 0.1. The C/D ratio > 0.3 or a binocular difference of >0.2 could be regarded as one of the criteria of newborn glaucoma. Group (2): the normal ratio ranged from 0.1-0.2. Group (3): the normal ratio ranged from 0.2-0.3. The highest ratio 0.7 was found in two eyes. An asymmetry of 0.2 or more in the C/D ratios of the eyes was found in 4.8% of the children. Conclusion: C/D ratio > 0.3 and asymmetry of 0.2 is suggestive of glaucoma especially in infants of lower age group.展开更多
Optic disc drusen are eye abnormalities characterised by calcific degeneration affecting some axons of the optic nerve. Alport syndrome is a collagen IV related nephropathy with well-described pathognomonic ocular fea...Optic disc drusen are eye abnormalities characterised by calcific degeneration affecting some axons of the optic nerve. Alport syndrome is a collagen IV related nephropathy with well-described pathognomonic ocular features. We present the case of a child who following series of investigations was found to have bilateral optic disc drusen, and eventually a further diagnosis of Alport syndrome confirmed. Literature is clear on the underlined aetiology responsible for both renal and extra renal abnormalities of Alport syndrome, which is not related to development of optic disc drusen. The case described makes it pertinent that not only the associated eye signs of Alport syndrome are monitored, but also early detection of other possible co-existing diseases that may influence outcomes.展开更多
The machining surface integrity of aero-engine turbine disc slots has a significant impact on their fatigue life and service performance,and achieving efficiency and high-precision machining is still a great challenge...The machining surface integrity of aero-engine turbine disc slots has a significant impact on their fatigue life and service performance,and achieving efficiency and high-precision machining is still a great challenge.The high machining requirements of future aeroengine turbine disc slots will be difficult to satisfy using the broaching method.In addition,existing methods of slot machin-ing face difficulties in ensuring surface integrity.This study explored a cup shaped electroplated Cubic Boron Nitride(CBN)abrasive wheel for profile grinding the turbine disc slots of FGH96 powder metallurgy superalloy.The matrix structure of the cup shaped abrasive wheel was designed and verified.A profile grinding experiment was conducted for fir-tree slots on a five-axis machining center.The accuracy and the surface integrity were analyzed.Results show that the key dimension detection results of the slots were within the allowable tolerance range.Meanwhile,an average sur-face roughness Ra of 0.55μm was achieved,the residual stress was compressive,the plastic defor-mation layer thickness was less than 5μm,and the hardening layer thickness was less than 20μm.The research findings provide a new approach to machining the slots of aviation engine turbine discs and guidance for the high-quality processing of complex components.展开更多
Aim: To present a case of hamartoma of the optic disc and Retinal Pigment Epithelium (RPE) and follow up of the visual function over three-years period. Methods: A seventeen-year-old boy has observed reduced visual ac...Aim: To present a case of hamartoma of the optic disc and Retinal Pigment Epithelium (RPE) and follow up of the visual function over three-years period. Methods: A seventeen-year-old boy has observed reduced visual acuity in his left eye. The visual acuity was 0.2 and there was RAPD in the left eye. Fundoscopy revealed an elevation of the optic disc obscuring disc vessels with epiretinal gliosis. Fluorescein angiography demonstrated hyperfluorescent saccular dilatations with leakage in the late phase. Ocular Coherence Tomography (OCT) showed hyperreflective elevation of the optic disc and epiretinal membrane. There was a juxtapapillary scotoma in Semi-automated Kinetic Perimetry (SKP). There was no systemic diseases. Results of blood tests, CT and MRI of CNV were normal. Results: After 3 years period of the follow-up the visual acuity was 0.1 and there was a progression of the visual field defect to the altitudinal scotoma in the upper hemisphere. Fluorescein anhiography and OCT revealed the same. Conclusion: Hamartoma of RPE and optic disc is a rare condition consisting of glial, vascular and RPE cells. It should be differentiated from optic disc oedema and vascular tumors of the retina. Assessment of the visual function is very important in the longitudinal follow-up.展开更多
Scanning tunneling microscope (STM) is used to investigate the optical disc.The areas with and without data stampers are all observed carefully. Three-dimensional images of the disc surface clearly demonstrate the per...Scanning tunneling microscope (STM) is used to investigate the optical disc.The areas with and without data stampers are all observed carefully. Three-dimensional images of the disc surface clearly demonstrate the period, depth of the grooves and the shape of data stampers. Some phenomena of STM imaging are also discussed.展开更多
BACKGROUND To report an unusual case of bilateral optic disc coloboma associated with macular retinoschisis in the left eye.CASE SUMMARY A 37-year-old woman presented with complaints of blurred and distorted vision in...BACKGROUND To report an unusual case of bilateral optic disc coloboma associated with macular retinoschisis in the left eye.CASE SUMMARY A 37-year-old woman presented with complaints of blurred and distorted vision in her left eye for more than 1 year.Fundus examination demonstrated choroidal atrophy around the optic disc in both eyes,with a cup-to-disc ratio of 0.9.Serous retinal detachment in the macular area of the left eye.Left eye macular blood flow imaging optical coherence tomography(Angio-OCT)showed macular retinal serous cleavage.En-face OCT showed that the canal gully-like structure formed by the defect of the optic disc nerve fiber layer between the optic disc and macula,serous detachment area was connected with the enlarged optic disc coloboma through the canal gully-like structure,and the fluid leaked from the enlarged and thinned optic disc coloboma into the retinal layer of the macular area.Patients with optic disc abnormalities and macular degeneration must be monitored appropriately.During the follow-up period,the use of optic disc stereography and 3D-OCT,en-face,and Angio-OCT imaging can clarify the correlation between macular retinoschisis and optic disc coloboma.CONCLUSION Macular retinoschisis may be owing to the combined force of disc edge loss,enlarged optic disc coloboma,the canal gully-like structure formed by the defect of the nerve fiber layer around the optic disc,and the traction of the posterior vitreous cortex.展开更多
基金funded byResearchers Supporting Project Number(RSPD2024R 553),King Saud University,Riyadh,Saudi Arabia.
文摘In this work,we aim to introduce some modifications to the Anam-Net deep neural network(DNN)model for segmenting optic cup(OC)and optic disc(OD)in retinal fundus images to estimate the cup-to-disc ratio(CDR).The CDR is a reliable measure for the early diagnosis of Glaucoma.In this study,we developed a lightweight DNN model for OC and OD segmentation in retinal fundus images.Our DNN model is based on modifications to Anam-Net,incorporating an anamorphic depth embedding block.To reduce computational complexity,we employ a fixed filter size for all convolution layers in the encoder and decoder stages as the network deepens.This modification significantly reduces the number of trainable parameters,making the model lightweight and suitable for resource-constrained applications.We evaluate the performance of the developed model using two publicly available retinal image databases,namely RIM-ONE and Drishti-GS.The results demonstrate promising OC segmentation performance across most standard evaluation metrics while achieving analogous results for OD segmentation.We used two retinal fundus image databases named RIM-ONE and Drishti-GS that contained 159 images and 101 retinal images,respectively.For OD segmentation using the RIM-ONE we obtain an f1-score(F1),Jaccard coefficient(JC),and overlapping error(OE)of 0.950,0.9219,and 0.0781,respectively.Similarly,for OC segmentation using the same databases,we achieve scores of 0.8481(F1),0.7428(JC),and 0.2572(OE).Based on these experimental results and the significantly lower number of trainable parameters,we conclude that the developed model is highly suitable for the early diagnosis of glaucoma by accurately estimating the CDR.
基金supported by the National Natural Science Foundation of China(Nos.61502537 and 61573380)the Hunan Provincial Natural Science Foundation of China(Nos.2018JJ3681 and 2016JJ2150)+3 种基金the Open Project Fund of Key Lab of Digital Signal and Image Processing of Guangdong Province(No.2018GDDSIPL-01)the Mutual Creation Project for Teachers and Students(No.2018gczd022)the 111 Project(No.B18059)the Fundamental Research Funds for the Central Universities of Central South University(No.2018zzts576)
文摘Glaucoma as an irreversible blinding opioid neuropathy disease, its blindness rate is the second only after cataract in the world. The optic cup-to-disc ratio(CDR) is generally considered to be an important clinical indicator for judging the severity of glaucoma by ophthalmologists from retinal fundus image. In this letter, we propose an automatic CDR measurement method that consists of a novel optic disc localization method and a simultaneous optic disc and cup segmentation network based on the improved U shape deep convolutional neural network. Experimental results demonstrate that the proposed method can achieve superior performance when compared with other existing methods. Thus, our method can be used as a powerful tool for glaucoma-assisted diagnosis.
文摘Glaucoma is an eye disease that usually occurs with the increased Intra-Ocular Pressure(IOP),which damages the vision of eyes.So,detecting and classifying Glaucoma is an important and demanding task in recent days.For this purpose,some of the clustering and segmentation techniques are proposed in the existing works.But,it has some drawbacks that include ineficient,inaccurate and estimates only the affected area.In order to solve these issues,a Neighboring Differential Clustering(NDC)-Intensity V ariation Making(IVM)are proposed in this paper.The main intention of this work is to extract and diagnose the abnormal retinal image by identifying the optic disc.This work includes three stages such as,preprocessing,clustering and segmentation.At first,the given retinal image is preprocessed by using the Gaussian Mask Updated(GMU)model for eliminating the noise and improving the quality of the image.Then,the cluster is formed by extracting the threshold and patterns with the help of NDC technique.In the segmentation stage,the weight is calculated for pixel matching and ROI extraction by using the proposed IVM method.Here,the novelty is presented in the clustering and segmentation processes by developing NDC and IVM algorithms for accurate Glaucoma identification.In experiments,the results of both existing and proposed techniques are evaluated in terms of sensitivity,specificity,accuracy,Hausdorff distance,Jaccard and dice metrics.
文摘AIM:To compare the cup-to-disc ratio(CDR)and optic disc morphology between eyes with congenital cataract and eyes without cataract in children under 3 years old.METHODS:This study included 63 patients with bilateral congenital cataract(mean age of 55.72±46.50wk,44 were male),33 patients with unilateral cataract(mean age of 56.63±33.23wk,16 were male),and 31 age-matched healthy children(mean age of 55.80±29.29wk,17 were male).Fundus photographs were taken with the RetCam 3 system.The horizontal-to-vertical disc diameter ratio(HVDR)was used as an index to describe the oval form of the optic disc.RESULTS:The horizontal cup-to-disc ratio(HCDR),vertical cup-to-disc ratio(VCDR)and HVDR of cataract eyes in unilateral groups were significantly smaller than those of the normal eyes(P<0.05).In the unilateral group,the HCDR,VCDR and HVDR of cataract eyes were significantly smaller than those in fellow eyes(P<0.05).The HVDR of eyes in the bilateral group was significantly smaller than those in the age-matched normal eyes(P<0.001).The form of optic disc of the cataract eyes in both the bilateral and unilateral groups was more vertical-oral than the normal eyes in the unilateral and the age-matched groups(P<0.05).CONCLUSION:Our results show that eyes with congenital cataract has a smaller HVDR and the form of the optic disc tended to be vertical-oval in young children.
文摘AIM:To explore the impact of insulin-like growth factor-1 receptorα(IGF-1Rα)on the differentiation fate of optic-cupderived retinal stem cells(OC-RSCs)into retinal ganglion cells(RGCs)in vitro.METHODS:OC-RSCs were isolated from optic cups of rats on embryonic day 12.5,and high-purity OC-RSCs were obtained by conditioned culture and passage.Differentiation of OC-RSCs into RGCs under different serum concentrations was examined using flow cytometry,and the serum concentration with high interference with differentiation ratio was selected.Furthermore,the effect of blocking IGF-1Rαon the differentiation of OC-RSCs into RGCs was analyzed through immunocytochemistry and Western blotting.RESULTS:Immunohistochemical analysis revealed IGF-1Rαwas highly expressed in rat embryos at day 12.5.OC-RSCs were isolated and purified,and high-purity OCRSCs were obtained.When 2.5%serum was administered,the ratio of differentiated RGCs(Thy-1.1 positive)decreased significantly,and the results of immunoblotting also confirmed the blockade of IGF-1Rαreduced Thy-1.1 protein expression.CONCLUSION:IGF-1Rαblocking can reduce the differentiation of OC-RSCs into RGCs.
基金Supported by the National Key Project of Research and Development Plan(No.2017YFA0104101)
文摘Myopia,a worldwide condition,is a multifactorial disease resulting in many ocular complications.Early onset of myopia has a great tendency to develop high myopia and pathological myopia later in life.The pathophysiology and progression of myopia is still unclear.Owing to its involving in visual function,optic disc and peripapillary change in high myopia can＇t be neglected,and it may help in better understanding of the pathophysiology or mechanism of myopia progression.Recently,advanced imaging techniques have been developed,such as optical coherence tomography（OCT）,allowing for better detecting of optic disc and peripapillary change.OCT is a highresolution and noninvasive measurement for detection of ocular structure.Herein,we provide an updated review of optic disc and peripapillary change in OCT image,including its characteristics and clinical significance.We also propose some problems needed further investigation.
文摘AIM:To explore changes in the optic disc and peripapillary atrophy(PPA)in school-age children with ametropia using color fundus photography combined with artificial intelligence(AI)technology.METHODS:Based on the retrospective case-controlled study,226 eyes of 113 children aged aged 6–12y were enrolled from October 2021 to May 2022.According to the results of spherical equivalent(SE),the children were divided into four groups:low myopia group(66 eyes),moderate myopia group(60 eyes),high myopia group(50 eyes)and emmetropia control group(50 eyes).All subjects underwent un-aided visual acuity,dilated pupil optometry,best-corrected visual acuity(BCVA),intraocular pressure,ocular axis measurement and color fundus photography.RESULTS:The width of PPA,horizontal diameter ratio of PPA to the optic disc and area ratio of PPA to the optic disc were significantly different among the four groups(P<0.05).The width of the nasal and temporal neuroretinal rim,the roundness of the optic disc,the height of PPA,the vertical diameter ratio of PPA to the optic disc,and the average density of PPA in the high myopia group were significantly different compared with the other three groups(P<0.05).There were strong negative correlations between SE and area ratio of PPA to the optic disc(r=-0.812,P<0.001)and strong positive correlation between axial length(AL)and area ratio of PPA to the optic disc(r=0.736,P<0.001).CONCLUSION:In school-age children with high myopia,the nasal and temporal neuroretinal rims are narrowed and even lost,which have high sensitivity.The area ratio of the PPA to the optic disc could be used as an early predictor of myopia progression,which is of great significance for the development prevention and management of myopia.
文摘AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control subjects were enrolled in the study.One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm^(2) rectangular area.Radial peripapillary capillary(RPC)density,peripapillary retinal nerve fiber layer(pRNFL)thickness,cup volume,rim area,disc area,cup-to-disc(c/d)area ratio,and vertical c/d ratio were obtained automatically using device software.Automated parapapillary choroidal microvasculature(PPCMv)density was calculated using MATLAB software.When the vertical c/d ratio of the optic disc was absent or small cup,it was considered as a crowded disc.RESULTS:The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes(P=0.740).There was no difference in pRNFL between the two groups(P=0.102).There were no differences in RPC density in whole image(P=0.826)and peripapillary region(P=0.923),but inside disc RPC density was higher in crowded optic discs(P=0.003).The PPCMv density in the inner-hemisuperior region was also lower in crowded discs(P=0.026).The pRNFL thickness was positively correlated with peripapillary RPC density(r=0.498,P<0.001).The inside disc RPC density was negatively correlated with c/d area ratio(r=-0.341,P=0.002).CONCLUSION:The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs.
文摘Dear Editor,We present the first reported case of nasal optic disc pit resulting in serous detachment of the macula. Optic disc pit is a rare congenital anomaly occurring in one out of 11 000 people. The appearance is a localized round or oval depression in that is grey, yellow or black in colour depending on the amount of glial tissue present.
文摘AIMTo evaluate the possible relationship of optic disc area with retina nerve fiber layer in different glaucoma subtypes.METHODSOne eye each was chosen from 45 patients with ocular hypertension, 45 patients with primary open angle glaucoma, 45 patients with pseudoexfoliation glaucoma and 45 healthy controls followed in our hospital. The records of the patients were reviewed retrospectively. Optic disc area and circumpapillary retina nerve fiber layer measurements were obtained using optical coherence tomography. Central corneal thickness was measured by ultrasound pachymetry.RESULTSThe median disc area in the patients with primary open angle glaucoma was significantly higher than the patients with ocular hypertension (2.19 vs 1.90 mm<sup>2</sup>, P=0.030). The median retina nerve fiber layer was thinner in the patients with primary open angle glaucoma and pseudoexfoliation glaucoma than the patients with ocular hypertension for superior, inferior and temporal quadrants. After adjustment for age, no difference in central corneal thickness was found between the groups. Greater disc area was associated with thicker retinal nerve fiber layer for superior, inferior and nasal quadrants in the patients with primary open angle glaucoma. There was no correlation between disc area and central corneal thickness measurements of the groups.CONCLUSIONDisc size affects the retinal nerve fiber layer thickness in eyes with primary open angle glaucoma and is a possible risk factor for glaucomatous optic nerve damage.
基金Deanship of Scientific Research,Princess Nourah bint Abdulrahman University,through the Program of Research Project Funding after Publication,Grant No(43-PRFA-P-31).
文摘Glaucoma disease causes irreversible damage to the optical nerve and it has the potential to cause permanent loss of vision.Glaucoma ranks as the second most prevalent cause of permanent blindness.Traditional glaucoma diagnosis requires a highly experienced specialist,costly equipment,and a lengthy wait time.For automatic glaucoma detection,state-of-the-art glaucoma detection methods include a segmentation-based method to calculate the cup-to-disc ratio.Other methods include multi-label segmentation networks and learning-based methods and rely on hand-crafted features.Localizing the optic disc(OD)is one of the key features in retinal images for detecting retinal diseases,especially for glaucoma disease detection.The approach presented in this study is based on deep classifiers for OD segmentation and glaucoma detection.First,the optic disc detection process is based on object detection using a Mask Region-Based Convolutional Neural Network(Mask-RCNN).The OD detection task was validated using the Dice score,intersection over union,and accuracy metrics.The OD region is then fed into the second stage for glaucoma detection.Therefore,considering only the OD area for glaucoma detection will reduce the number of classification artifacts by limiting the assessment to the optic disc area.For this task,VGG-16(Visual Geometry Group),Resnet-18(Residual Network),and Inception-v3 were pre-trained and fine-tuned.We also used the Support Vector Machine Classifier.The feature-based method uses region content features obtained by Histogram of Oriented Gradients(HOG)and Gabor Filters.The final decision is based on weighted fusion.A comparison of the obtained results from all classification approaches is provided.Classification metrics including accuracy and ROC curve are compared for each classification method.The novelty of this research project is the integration of automatic OD detection and glaucoma diagnosis in a global method.Moreover,the fusion-based decision system uses the glaucoma detection result obtained using several convolutional deep neural networks and the support vector machine classifier.These classification methods contribute to producing robust classification results.This method was evaluated using well-known retinal images available for research work and a combined dataset including retinal images with and without pathology.The performance of the models was tested on two public datasets and a combined dataset and was compared to similar research.The research findings show the potential of this methodology in the early detection of glaucoma,which will reduce diagnosis time and increase detection efficiency.The glaucoma assessment achieves about 98%accuracy in the classification rate,which is close to and even higher than that of state-of-the-art methods.The designed detection model may be used in telemedicine,healthcare,and computer-aided diagnosis systems.
文摘Background: Optic disc oedema has various underlying pathologies, however, unless visually disabling does not usually bring a patient to the physician. The more common symptoms of headache, nausea and vomiting lead to the incidental detection of bilateral disc oedema [1]. Optic disc oedema seen following spinal surgery is usually associated with visual acuity changes and often goes by the acronym POVL (Peri/ postoperative visual loss) wherein, as the name goes, visual acuity changes are profound [2] [3] [4]. Purpose: We would like to highlight a case of transient Bilateral Optic Disc oedema following Lumbar spinal surgery maintaining normal visual acuity and attaining spontaneous resolution. Case Report: A 42-year-old female presented with transient obscuration of vision and flashes of light post an uneventful lumbar spinal surgery. Ophthalmic evaluation revealed normal visual acuity and pupils but marked disc edema right more significant than left. There was no colour vision deficit, neither any field changes. By a process of exclusion, it was likely the patient had developed bilateral disc oedema secondary to the spinal surgery. On follow-up 6 weeks and 3 months later, the oedema had completely settled and visual acuity remained at 6/6. Conclusion: Optic disc oedema can be unilateral or bilateral with some of the uncommon conditions mentioned secondary to spinal surgery, however, in those situations, visual loss has been severe and permanent. Our case is unusual in its combination of disc edema with normal acuity along with its transient nature and resolution and to our knowledge, has not been published before.
基金Science and technology program of Guang-dong Province The location of susceptibility gene of primary open angle glaucoma (No.2008B030301)
文摘Purpose:To evaluate the changes of optic disc parameters in primary open angle glaucoma(POAG)patients after surgical and medical treatment,.and analyze the determinants of these changes.Methods:.A total of 67 patients were enrolled in this study.Thirty nine patients.(40 eyes) underwent trabeculectomy and 28 patients(32 eyes).received intra-ocular pressure(IOP) lowering medical therapy..All subjects underwent bilateral routine ocular examination and Heidelberg retina tomography.(HRT) before treatment and 2 weeks,.1 month,3 months,.6 months and 1 year after treatment..Changes in optic disc parameters in both the surgical and medical groups were analyzed,as was the influence of disease severity and IOP reduction on these changes.Results:.In the surgical group,the average preoperative IOP was 32.8±8.64 mmHg,.which showed a significant decline at each post-operative visit..Most optic disc parameters measured by HRT were significantly improved after trabeculectomy.(P=0.001～0.01),.though the amount of improvement declined gradually during the post-operative period.Rim volume (RV),cup shape measure (CSM),mean RNFL (mRNFL),RNFL cross sectional area (RNFLA) and vertical cup-to-disc ratio (C/D) still remained significantly below the pre-operative mean one year after surgery.In the medical group,the mean IOP before treatment was 24.8±4.32 mmHg and remained < 21 mmHg on all subsequent post-treatment visits.However,no significant changes in optic disc parameters were found after initiation of medical treatment(F=0.52～2.21,P=0.75～0.07).In the surgical group,the extent of reduction of IOP was positively correlated with the improvement in RV,CSM and vertical C/D(r=0.41～0.58,P=0.001～0.04) at one year after trabeculectomy.The absolute value of the mean deviation on visual field testing was negatively correlated with the improvement of RV and CSM (r=-0.43～-0.62,P=0.03～0.001).Conclusion:Improvement in optic disc parameters occurred more commonly after surgical than medical treatment in POAG patients.The amount of reduction of IOP was correlated with the extent of this improvement,which may be more limited in more severe glaucoma.
文摘AIM:To evaluate concordance between the clinical assessment of glaucomatous progression of the optic disc photography and progression identified by Heidelberg Retina Tomograph(HRT)in patients with suspected primary juvenile open angle glaucoma(JOAG).METHODS:Optic disc photographs and corresponding HRTⅡseries were reviewed.Optic disc changes between first and final photographs were noted as well as progression identified by HRT topographic change analysis(TCA)and rim area regression line(RARL)Agreement between progression indentified by photography and HRT methods was assessed.Progression,determined from optic disc photographs by consensus assessment was used as the reference standard.RESULTS:A total of 31 patients(59 eyes)with suspected JOAG were studied.Agreement for progression/no progression between TCA and photography was obtained in 4 progressing eyes and 38stable eyes(71.19%,k=0.11).Agreement for progression/no progression between RARL and photography was detected in 5 progressing eyes and in 34 stable eyes(66.10%,k=0.15).The number of HRT per patient was statistically higher in the progressing group(P=0.034).CONCLUSION:Agreement for detection of longitudinal changes between photography and HRT analysis was poor.One way to improve the chance of discovery of the progression could be increasing the number of HRT examinations.
文摘Purpose: The aim of this study is early detection of increased cup to disc ratio and a survey study of cup-disc ratio in Egyptian children age group less than 15 years. Methods: Three hundred and eighty-two (382) children were enrolled in this study. They were classified into three age groups;infants’ Group (1) from 0-2 years, preschool Group (2) from 2-6 years and school children Group (3) from 6-15 years old. C/D ratio was measured for each child. Results: In Group (1), normal C/D ratio ranged from 0 to 0.1. The C/D ratio > 0.3 or a binocular difference of >0.2 could be regarded as one of the criteria of newborn glaucoma. Group (2): the normal ratio ranged from 0.1-0.2. Group (3): the normal ratio ranged from 0.2-0.3. The highest ratio 0.7 was found in two eyes. An asymmetry of 0.2 or more in the C/D ratios of the eyes was found in 4.8% of the children. Conclusion: C/D ratio > 0.3 and asymmetry of 0.2 is suggestive of glaucoma especially in infants of lower age group.
文摘Optic disc drusen are eye abnormalities characterised by calcific degeneration affecting some axons of the optic nerve. Alport syndrome is a collagen IV related nephropathy with well-described pathognomonic ocular features. We present the case of a child who following series of investigations was found to have bilateral optic disc drusen, and eventually a further diagnosis of Alport syndrome confirmed. Literature is clear on the underlined aetiology responsible for both renal and extra renal abnormalities of Alport syndrome, which is not related to development of optic disc drusen. The case described makes it pertinent that not only the associated eye signs of Alport syndrome are monitored, but also early detection of other possible co-existing diseases that may influence outcomes.
基金supported by the National Natural Science Foundation of China (Nos.52305477,52375447,52305474)Major Special Projects of Aero-engine and Gas Turbine (No.2017-VII-0002-0095)+4 种基金the Special Fund of Taishan Scholars Project (No.tsqn202211179)the Youth Talent Promotion Project in Shandong (No.SDAST2021qt12)the Natural Science Foundation of Shandong Province (Nos.ZR2023QE057,ZR2022QE028,ZR2021QE116,and ZR2020KE027)Qingdao Science and Technology Planning Park Cultivation Plan (No.23-1-5-yqpy-17-qy)the Natural Science Foundation of Jiangsu Province (No.BK20210407).
文摘The machining surface integrity of aero-engine turbine disc slots has a significant impact on their fatigue life and service performance,and achieving efficiency and high-precision machining is still a great challenge.The high machining requirements of future aeroengine turbine disc slots will be difficult to satisfy using the broaching method.In addition,existing methods of slot machin-ing face difficulties in ensuring surface integrity.This study explored a cup shaped electroplated Cubic Boron Nitride(CBN)abrasive wheel for profile grinding the turbine disc slots of FGH96 powder metallurgy superalloy.The matrix structure of the cup shaped abrasive wheel was designed and verified.A profile grinding experiment was conducted for fir-tree slots on a five-axis machining center.The accuracy and the surface integrity were analyzed.Results show that the key dimension detection results of the slots were within the allowable tolerance range.Meanwhile,an average sur-face roughness Ra of 0.55μm was achieved,the residual stress was compressive,the plastic defor-mation layer thickness was less than 5μm,and the hardening layer thickness was less than 20μm.The research findings provide a new approach to machining the slots of aviation engine turbine discs and guidance for the high-quality processing of complex components.
文摘Aim: To present a case of hamartoma of the optic disc and Retinal Pigment Epithelium (RPE) and follow up of the visual function over three-years period. Methods: A seventeen-year-old boy has observed reduced visual acuity in his left eye. The visual acuity was 0.2 and there was RAPD in the left eye. Fundoscopy revealed an elevation of the optic disc obscuring disc vessels with epiretinal gliosis. Fluorescein angiography demonstrated hyperfluorescent saccular dilatations with leakage in the late phase. Ocular Coherence Tomography (OCT) showed hyperreflective elevation of the optic disc and epiretinal membrane. There was a juxtapapillary scotoma in Semi-automated Kinetic Perimetry (SKP). There was no systemic diseases. Results of blood tests, CT and MRI of CNV were normal. Results: After 3 years period of the follow-up the visual acuity was 0.1 and there was a progression of the visual field defect to the altitudinal scotoma in the upper hemisphere. Fluorescein anhiography and OCT revealed the same. Conclusion: Hamartoma of RPE and optic disc is a rare condition consisting of glial, vascular and RPE cells. It should be differentiated from optic disc oedema and vascular tumors of the retina. Assessment of the visual function is very important in the longitudinal follow-up.
文摘Scanning tunneling microscope (STM) is used to investigate the optical disc.The areas with and without data stampers are all observed carefully. Three-dimensional images of the disc surface clearly demonstrate the period, depth of the grooves and the shape of data stampers. Some phenomena of STM imaging are also discussed.
文摘BACKGROUND To report an unusual case of bilateral optic disc coloboma associated with macular retinoschisis in the left eye.CASE SUMMARY A 37-year-old woman presented with complaints of blurred and distorted vision in her left eye for more than 1 year.Fundus examination demonstrated choroidal atrophy around the optic disc in both eyes,with a cup-to-disc ratio of 0.9.Serous retinal detachment in the macular area of the left eye.Left eye macular blood flow imaging optical coherence tomography(Angio-OCT)showed macular retinal serous cleavage.En-face OCT showed that the canal gully-like structure formed by the defect of the optic disc nerve fiber layer between the optic disc and macula,serous detachment area was connected with the enlarged optic disc coloboma through the canal gully-like structure,and the fluid leaked from the enlarged and thinned optic disc coloboma into the retinal layer of the macular area.Patients with optic disc abnormalities and macular degeneration must be monitored appropriately.During the follow-up period,the use of optic disc stereography and 3D-OCT,en-face,and Angio-OCT imaging can clarify the correlation between macular retinoschisis and optic disc coloboma.CONCLUSION Macular retinoschisis may be owing to the combined force of disc edge loss,enlarged optic disc coloboma,the canal gully-like structure formed by the defect of the nerve fiber layer around the optic disc,and the traction of the posterior vitreous cortex.
