Vitreoretinal Lymphoma with Intraretinal Infiltration, Simulating Retinal Necrosis.

PURPOSE: To describe the clinical features and outcomes of vitreoretinal lymphoma (VRL) with intraretinal infiltration, a pseudonecrotic variant. DESIGN: Retrospective, comparative analysis. SUBJECTS: Patients with biopsy-proven VRL at a single center from August 2016 to April 2022. METHODS: A retrospective record review was conducted for clinical, imaging, and laboratory data. MAIN OUTCOME MEASURES: Clinical features, visual, and survival outcomes. RESULTS: We included 67 eyes of 40 patients with biopsy-proven VRL. Pseudonecrotic retinal lesions (PRLs) were found in 24 (35.8%) eyes of 19 patients; these eyes were classified as a pseudonecrotic variant, whereas the remaining 43 (64.2%) eyes were classified as nonnecrotic. Comparison (pseudonecrotic vs. nonnecrotic) revealed that eyes with PRLs at presentation had a worse median best-corrected visual acuity (BCVA; 2.4 vs. 0.5 logarithm of the minimum angle of resolution [logMAR], P < 0.0001) and severe ocular manifestations (P < 0.0001), including optic disc swelling (79.2% vs. 0%), retinal vasculitis (93.8% vs. 4.7%), retinal hemorrhage (83.3% vs. 0%), and retinal detachment (RD) (79.2% vs. 0%). Follow-up data were available for 20 eyes (17 patients) in the pseudonecrotic group and 43 eyes (21 patients) in the nonnecrotic group. An equally worse median BCVA was noted in pseudonecrotic eyes at 6 months after treatment and the final follow-up as compared with nonnecrotic eyes (2.4 vs. 0.3 logMAR, P < 0.0001). The median follow-up period did not differ significantly (16.6 vs. 18.4 months, P = 0.47). Initial BCVA (ß = 0.300, P = 0.003), presence of anterior chamber cell (ß = 0.472, P = 0.013), and RD (ß = 1.137, P < 0.0001) were significantly associated with poor visual outcomes in multivariate linear regression analysis (adjusted R2 = 0.693). There were no significant differences in survival outcomes. CONCLUSION: Vitreoretinal lymphoma can present as pseudonecrotic retinopathy, with more advanced clinical presentations and worse final visual outcomes. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

A critical review on diagnosis of diabetic retinopathy using machine learning and deep learning.

Diabetic Retinopathy (DR) is a health condition caused due to Diabetes Mellitus (DM). It causes vision problems and blindness due to disfigurement of human retina. According to statistics, 80% of diabetes patients battling from long diabetic period of 15 to 20 years, suffer from DR. Hence, it has become a dangerous threat to the health and life of people. To overcome DR, manual diagnosis of the disease is feasible but overwhelming and cumbersome at the same time and hence requires a revolutionary method. Thus, such a health condition necessitates primary recognition and diagnosis to prevent DR from developing into severe stages and prevent blindness. Innumerable Machine Learning (ML) models are proposed by researchers across the globe, to achieve this purpose. Various feature extraction techniques are proposed for extraction of DR features for early detection. However, traditional ML models have shown either meagre generalization throughout feature extraction and classification for deploying smaller datasets or consumes more of training time causing inefficiency in prediction while using larger datasets. Hence Deep Learning (DL), a new domain of ML, is introduced. DL models can handle a smaller dataset with help of efficient data processing techniques. However, they generally incorporate larger datasets for their deep architectures to enhance performance in feature extraction and image classification. This paper gives a detailed review on DR, its features, causes, ML models, state-of-the-art DL models, challenges, comparisons and future directions, for early detection of DR.

An uncommon cold of the retina.

A 39-year-old woman with progressive loss of vision left eye was referred for evaluation. Notably, she had been diagnosed with COVID-19 two weeks beforehand. Examination and ancillary testing confirmed atypical multifocal evanescent white dot syndrome. Possible other masquerades were excluded. A few weeks later, visual acuity improved in the left eye and symptoms resolved together with normalization of ancillary testing, including visual fields.

Diabetic retinopathy classification based on multipath CNN and machine learning classifiers.

Eye care professionals generally use fundoscopy to confirm the occurrence of Diabetic Retinopathy (DR) in patients. Early DR detection and accurate DR grading are critical for the care and management of this disease. This work proposes an automated DR grading method in which features can be extracted from the fundus images and categorized based on severity using deep learning and Machine Learning (ML) algorithms. A Multipath Convolutional Neural Network (M-CNN) is used for global and local feature extraction from images. Then, a machine learning classifier is used to categorize the input according to the severity. The proposed model is evaluated across different publicly available databases (IDRiD, Kaggle (for DR detection), and MESSIDOR) and different ML classifiers (Support Vector Machine (SVM), Random Forest, and J48). The metrics selected for model evaluation are the False Positive Rate (FPR), Specificity, Precision, Recall, F1-score, K-score, and Accuracy. The experiments show that the best response is produced by the M-CNN network with the J48 classifier. The classifiers are evaluated across the pre-trained network features and existing DR grading methods. The average accuracy obtained for the proposed work is 99.62% for DR grading. The experiments and evaluation results show that the proposed method works well for accurate DR grading and early disease detection.

Recurrent Neuroretinitis: A Unique Presentation of Behçet's Disease in a Child.

We describe a case of Behçet's disease (BD) in a young child that presented with recurrent neuroretinitis and developed retinal lesions during follow-up. A 4.5-year-old girl presented with fever of 39.5°C, erythema nodosum in her legs, bilateral knee arthritis, and perineum aphthae. On ocular examination, visual acuity was 20/25 in both eyes. Right eye examination was normal and the left eye (LE) showed mild anterior and intermediate uveitis, normal optic disc, and a macular star appearance. Laboratory workup demonstrated elevated C-reactive protein levels, a normal abdominal ultrasound, and a normal colonoscopy. The patient was diagnosed with BD. One month post initial presentation, the patient presented with visual acuity of finger counting in the LE with significant anterior uveitis, mild intermediate uveitis, and recurrent neuroretinitis. Under treatment of IV methylprednisolone, oral betamethasone, infliximab, and colchicine, a complete systemic remission was noticed, and uveitis became quiescent. On last examination, 4.5 years post first presentation, visual acuity was 20/25 in both eyes and the LE demonstrated a remnant of a juxtafoveal retinal scar. To the best of our knowledge, this is the first case of neuroretinitis presenting as a manifestation of pediatric BD. Ophthalmologists should be aware of these unique manifestations of ocular BD.

Optomap ultrawide field imaging for detecting peripheral retinal lesions in 1725 high myopic eyes before implantable collamer lens surgery.

IMPORTANCE: Identifying peripheral retinal lesions in high myopia patients before implantable collamer lens (ICL) surgery by nonmydriatic Optomap ultrawide field imaging. BACKGROUND: To investigate specificity and sensitivity of nonmydriatic Optomap ultrawide field imaging for detecting peripheral retinal lesions in high myopia patients before ICL surgery. DESIGN: Hospital-based, cross-sectional study. PARTICIPANTS: A total of 1725 high myopic eyes of 897 ICL surgery candidates were included in this study. METHODS: Patients with high myopia were scheduled for routine ophthalmic examination before ICL implantation. Nonmydriatic Optomap ultrawide field imaging was applied for detecting potential peripheral retinal lesions before ICL surgery. MAIN OUTCOME MEASURES: Presence of peripheral retinal lesions. RESULTS: Of 1725 eyes, 344 (19.94%) had peripheral retinal lesions in total; 75 (4.35%) eyes had holes/tears; 313 (18.14%) eyes had peripheral retinal degenerations. Sensitivity of Optomap for detecting peripheral retinal holes/tears and degenerations were 57.33% (95% confidence interval [CI]: 45.38-68.69) and 65.18% (95% CI: 59.61-70.45). Specificity for peripheral retinal holes/tears and degenerations were 99.58% (95% CI: 99.13-99.83) and 99.08% (95% CI: 98.43-99.51), respectively. A total of 22.70% (32/141) of omitted peripheral retinal lesions under Optomap needed intervention. Longer axial length (odds ratio [OR]: 1.16, P < .01), more severe refractive error (OR: 1.05, P < .01) and older age (OR: 1.03, P < .01) were proved to be risk factors for peripheral retinal degenerations in high myopes. CONCLUSIONS AND RELEVANCE: Optomap ultrawide field imaging is a reliable adjunctive tool with high specificity and moderate sensitivity for identifying and recording peripheral retinal lesions in high myopes in preoperative examination. Nonmydriatic Optomap could not entirely replace Goldmann three-mirror contact lens in detecting peripheral retinal lesions in high myopia ICL candidates.

Analysis of the location of retinal lesions in central retinographies of patients with Type 2 diabetes.

PURPOSE: To describe the distribution of Type 2 DM retinal lesions and determine whether it is symmetrical between the two eyes, is random or follows a certain pattern. METHODS: Cross-sectional study of Type 2 DM patients who had been referred for an outpatients' ophthalmology visit for diabetic retinopathy screening in primary health care. Retinal photographic images were taken using central projection non-mydriatic retinography. The lesions under study were microaneurysms/haemorrhages, and hard and soft exudates. The lesions were placed numerically along the x- and y-axes obtained, with the fovea as the origin. RESULTS: From among the 94 patients included in the study, 4770 lesions were identified. The retinal lesions were not distributed randomly, but rather followed a determined pattern. The left eye exhibited more microaneurysms/haemorrhages and hard exudates of a greater density in the central retina than was found in the right eye. Furthermore, more cells containing lesions were found in the upper temporal quadrants, (especially in the left eye), and tended to be more central in the left eye than in the right, while the hard exudates were more central than the microaneurysms/haemorrhages. CONCLUSION: The distribution of DR lesions is neither homogeneous nor random but rather follows a determined pattern for both microaneurysms/haemorrhages and hard exudates. This distribution means that the areas of the retina most vulnerable to metabolic alteration can be identified. The results may be useful for automated DR detection algorithms and for determining the underlying vascular and non-vascular physiopathological mechanisms that can explain these differences.

Upregulation of Lysyl Oxidase Expression in Vitreous of Diabetic Subjects: Implications for Diabetic Retinopathy.

Animal studies have shown diabetes-induced lysyl oxidase (LOX) upregulation promotes blood-retinal-barrier breakdown and retinal vascular cell loss associated with diabetic retinopathy (DR). However, it is unclear whether changes in LOX expression contribute to the development and progression of DR. To determine if vitreous LOX levels are altered in patients with DR, 31 vitreous specimens from subjects with advanced proliferative DR (PDR), and 27 from non-diabetics were examined. The two groups were age- and gender-matched (57 ± 12 yrs vs. 53 ± 18 yrs; 19 males and 12 females vs. 17 males and 10 females). Vitreous samples obtained during vitrectomy were assessed for LOX levels using ELISA. LOX was detected in a larger number of PDR subjects (58%) than in non-diabetic subjects (15%). Additionally, ELISA measurements showed a significant increase in LOX levels in the diabetic subjects with PDR, compared to those of non-diabetic subjects (68.3 ± 112 ng/mL vs. 2.1 ± 8.2 ng/mL; p < 0.01). No gender difference in vitreous LOX levels was observed in either the diabetic or non-diabetic groups. Findings support previous reports of increased LOX levels in retinas of diabetic animals and in retinal vascular cells in high glucose condition, raising the prospect of targeting LOX overexpression as a potential target for PDR treatment.

[Retinal manifestations of neuro-malaria or "malarial retinopathy" in Yaoundé]. / Atteintes rétiniennes du neuro-paludisme ou « rétinopathie paludique ¼ à Yaoundé.

AIM: Contribute to the improvement of diagnostic and prognostic approaches to treating children with neuro-malaria in Yaoundé. PATIENTS AND METHOD: A prospective and analytical study carried out in 2 hospitals of Yaoundé from October 2015 to March 2016. All patients aged 3 months to 15 years hospitalized for neuro-malaria in one of the 2 hospitals benefited from a fundus examination. The variables studied were: age, sex, Glasgow or Blantyre score, fundus examination and parasitaemia. For statistical analysis, we used the software R 3.3.0, Chi2, exact of Fisher or Kolmogorov-Smirnov tests with a significance P<5%. RESULTS: Out of the 178 children hospitalized during the study period, 44 had neuro-malaria (24.71%) and 26 (46 diseased eyes) among them presented retinal lesions at a frequency of 14.60%. The mean age was 5.54±3.49 years with a sex ratio of 1.09. The under 5-years-old were the most affected with 31 (70.45%) cases. The fundus lesions of 26 (59.09%) were retinal hemorrhages in 24 (54.54%), retinal whitening and vessel discoloration in 8 (18.18%) respectively. Papillary edema was associated in 4 (9.09%). Macular involvement was noted in 9 cases. These lesions were correlated with age, depth of coma, duration, and clinical course. The rate of parasitaemia did not affect their occurrence. CONCLUSION: Retinal lesions are frequent and serious during neuro-malaria in our environment, especially in children under five. They must therefore be an emphasis in the systematic exam to rule it out for a better prognostic evaluation and a fast and adequate multidisciplinary management.

Diabetic retinopathy detection and classification using hybrid feature set.

Complicated stages of diabetes are the major cause of Diabetic Retinopathy (DR) and no symptoms appear at the initial stage of DR. At the early stage diagnosis of DR, screening and treatment may reduce vision harm. In this work, an automated technique is applied for detection and classification of DR. A local contrast enhancement method is used on grayscale images to enhance the region of interest. An adaptive threshold method with mathematical morphology is used for the accurate lesions region segmentation. After that, the geometrical and statistical features are fused for better classification. The proposed method is validated on DIARETDB1, E-ophtha, Messidor, and local data sets with different metrics such as area under the curve (AUC) and accuracy (ACC).

Spatial distribution of early red lesions is a risk factor for development of vision-threatening diabetic retinopathy.

AIMS/HYPOTHESIS: Diabetic retinopathy is characterised by morphological lesions related to disturbances in retinal blood flow. It has previously been shown that the early development of retinal lesions temporal to the fovea may predict the development of treatment-requiring diabetic maculopathy. The aim of this study was to map accurately the area where lesions could predict progression to vision-threatening retinopathy. METHODS: The predictive value of the location of the earliest red lesions representing haemorrhages and/or microaneurysms was studied by comparing their occurrence in a group of individuals later developing vision-threatening diabetic retinopathy with that in a group matched with respect to diabetes type, age, sex and age of onset of diabetes mellitus who did not develop vision-threatening diabetic retinopathy during a similar observation period. RESULTS: The probability of progression to vision-threatening diabetic retinopathy was higher in a circular area temporal to the fovea, and the occurrence of the first lesions in this area was predictive of the development of vision-threatening diabetic retinopathy. The calculated peak value showed that the risk of progression was 39.5% higher than the average. There was no significant difference in the early distribution of lesions in participants later developing diabetic maculopathy or proliferative diabetic retinopathy. CONCLUSIONS/INTERPRETATION: The location of early red lesions in diabetic retinopathy is predictive of whether or not individuals will later develop vision-threatening diabetic retinopathy. This evidence should be incorporated into risk models used to recommend control intervals in screening programmes for diabetic retinopathy.

Adult cortical plasticity studied with chronically implanted electrode arrays.

The functional architecture of adult cerebral cortex retains a capacity for experience-dependent change. This is seen after focal binocular lesions as rapid changes in receptive field (RF) of the lesion projection zone (LPZ) in the primary visual cortex (V1). To study the dynamics of the circuitry underlying these changes longitudinally, we implanted microelectrode arrays in macaque (Macaca mulatta) V1, eliminating the possibility of sampling bias, which was a concern in previous studies. With this method, we observed a rapid initial recovery in the LPZ and, during the following weeks, 63-89% of the sites in the LPZ showed recovery of visual responses with significant position tuning. The RFs shifted ∼3° away from the scotoma. In the absence of a lesion, visual stimulation surrounding an artificial scotoma did not elicit visual responses, suggesting that the postlesion RF shifts resulted from cortical reorganization. Interestingly, although both spikes and LFPs gave consistent prelesion position tuning, only spikes reflected the postlesion remapping.

Utility of optomap panoramic 200Tx in postoperative fundus examination among cataract patients / 国际眼科杂志(Guoji Yanke Zazhi)

To investigate the utility of optomap panoramic 200Tx in screening fundus disease among the patients after cataract surgery. ●METHODS: From November 18 th to December 31st , 2013 all 146 post- cataract surgery patients were recruited. All non - mydriatic fundus images were taken with the optomap panoramic 200Tx and were diagnosed by one masked retinal specialist. Non - mydriatic direct ophthalmoscope exam and mydriatic slit-lamp lens exam were also done by other two masked specialists. Comparisons of the three methods were made. ●RESULTS: Among 146 patients ( 161 eyes), 40 eyes (24. 8%) of retinal lesions was detected by non-mydriatic direct ophthalmoscope exam, 59 ( 36. 7%) by non -mydriatic optomap 200Tx exam, and 61 (37. 9%) by slit-lamp lens exam. Nine eyes ( 5. 6%) needed medical intervention immediately. Results of optomap 200Tx exams and slit - lamp lens exams were similar without statistically significant difference ( P > 0. 05), better than direct ophthalmoscope exam ( P ● CONCLUSlON: Opacification of the refractive medium makes thorough fundus examination impossible. So post-operative fundus examination is highly necessary and should be a routine. Optomap panoramic 200Tx, which shows no statistically difference from mydriatc slit- lamp lens exam, is a convenient and feasible method in discovering fundus pathological changes.

Medullary thyroid carcinoma with metastasis to iridocorneal angle, a case report / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To report a rare case of medullary thyroid carcinoma (MTC) with iridocorneal angle metastasis.METHODS:A 28-year-old woman,a known case of sporadic MTC was referred to our hospital due to left eye mass involving iridiocorneal angle.Several months' later retinal evaluation revealed retinal involvement with some patches.RESULTS:After palliative laser photocoagulation ablation of the choroidal and angle lesions no signs of recurrence or any new lesion was detected.CONCLUSION:As we know this is the first report of MTC with iridocorneal angle metastasis in the literature.