[Diagnostic and treatment options for retinal arterial macroaneurysms in relation to our cases]. / Retinalis artéria macroaneurysmák diagnosztikai és kezelési lehetoségei eseteink kapcsán.

In our report, we present the history of four patients diagnosed with retinal arterial macroaneurysm associated with complications. Our aim is to present the varied appearance of the disease and to present the various therapeutic options. Retinal artery macroaneurysm is a rare, but potentially vision-threatening ophthalmic condition. Macroaneurysm develops from the arteriosclerotic transformation of the artery caused by high blood pressure. Macroaneurysms can be asymptomatic, or they can be associated with exudative or hemorrhagic complication which causes visual impairment. Depending on the symptoms, they can be treated with laser photocoagulation, intravitreal injections, or with vitrectomy. Our presented cases also illustrate that each case requires individual consideration because a uniform therapeutic recommendation is still yet to be developed. In addition to the ophthalmic treatment, it is extremely important to refer the patient to internal medicine. Orv Hetil. 2023; 164(42): 1673-1677.

Automatic segmentation of hyperreflective foci in OCT images.

BACKGROUND AND OBJECTIVE: The leading cause of vision loss in the Western World is Age-related Macular Degeneration (AMD), but together with modern medicines, tracking the number of Hyperreflective Foci (HF) on Optical Coherence Tomography (OCT) images should assist the treatment of patients. Here, we developed a framework based on deep learning for the automatic segmentation of HF in OCT images. METHODS: We collected OCT images and annotated them, then these images underwent image preprocessing, and feature extraction steps. Using the prepared data we trained different types of Conventional-, Deep- and Convolutional Neural Networks to perform the task of the automatic segmentation of HF. RESULTS: We evaluated the various Neural Networks, by performing HF segmentation of clinical data belonging to patients, whose data were excluded from the training process. The results suggest that our systems can achieve reasonably high Dice Coefficient values, and they are comparable with (i.e., in most cases above 95%) the similarity between manual annotations performed by different physicians. CONCLUSION: From the results, it can be concluded that neural networks can be used to accurately segment HF in OCT images. The results are sufficiently accurate for us to incorporate them into the next phase of the research, building a decision support system for everyday clinical practice.

The effect of ranibizumab and aflibercept treatment on the prevalence of outer retinal tubulation and its influence on retreatment in neovascular age-related macular degeneration.

BACKGROUND: We aimed to analyze the differences in the prevalence of outer retinal tubulation (ORT) in neovascular age-related macular degeneration (AMD) treated with anti-vascular endothelial growth factor (anti-VEGF) agents, either aflibercept or ranibizumab. Our further aim was to examine the changes in the frequency of injections of ranibizumab before and after ORT appearance. METHODS: Two hundred thirty six eyes of 230 patients were included in the study (184 eyes treated with ranibizumab by pro re nata regimen (PRN), 52 eyes with aflibercept bimonthly) and followed for 6-24 months. Using optical coherence tomography (OCT), the first appearance of ORT was documented, and fixed time point evaluations were also made every six months to determine the existence of ORT. The number of injections, the presence or absence of subretinal hyperreflective material (SHRM) at treatment initiation and visual acuity were also noted. RESULTS: The survival analysis with Cox proportional hazard model showed no significant difference between the ranibizumab and aflibercept groups in relation to the development of ORT (p = 0.79, hazard ratio 0.92). In the PRN treated ranibizumab group the number of injections showed significant decrease after ORT development (p = 0.004). When SHRM was present at treatment initiation the chance of developing ORT was 2.75 and 11.14 times higher in the ranibizumab and aflibercept groups, respectively. CONCLUSIONS: The prevalence of ORT increased over time independently from the chosen anti-VEGF drug. Our results suggest that upon the appearance of ORT a decrease in retreatments can be expected.

[Experience in 13-year follow-up of a melanocytoma of the optic nerve head]. / Látóidegfo-melanocytoma tizenhárom éves követésével szerzett tapasztalataink.

Thirteen years ago, a 35-year-old woman was found on routine ocular examination to have a pigmented tumor in her right eye, adjacent to the optic nerve head. The appearance of her fundus was suggestive of a melanocytoma. Her visual acuities were RE: 1.0 and LE: 1.0. Ultrasound examination revealed that the tumor diameter was 4.4 mm on the base and the maximal thickness was 2.7 mm. Fluorescein angiography showed a persistent hypofluorescence of the lesion. There were several additional examinations (e.g. determination of the visual field, measurement of the intraocular pressure, detection of visually evoked potentials, CT scan and MRI examination) to exclude a benign tumor of similar appearance, The patient underwent ocular examination every year. During the observation period a minor tumor enlargement occurred but there were no changes in the visual acuities. In the last two years minor signs of malignant transformation were found. The findings documented and illustrated here suggest that our methods were useful to differentiate the melanocytoma from a malignant melanoma, and no surgical interventions were needed to characterize or to remove the tumor. In addition, our patient has had good vision during the past 13 years.

Up-regulation of cerebral carbonic anhydrase by anoxic stress in piglets.

The resuscitation of asphyxiated babies is associated with changes in cerebral protein synthesis that can influence the neurological outcome. Insufficient gas exchange results in rapid shifts in extracellular and intracellular pH. Carbonic anhydrase (CA) plays an important role in buffering acute changes in pH in the brain. We investigated whether asphyxia/re-ventilation influences the expression of cerebral CA isoforms (CA-II, CA-III and CA-IV) in anaesthetized newborn pigs. The cerebral cortex, hippocampus, cerebellum and retina were sampled, and prepared for either CA immunohistochemistry or CA immunoblotting from piglets subjected to asphyxia (10 min) followed by 2-4 h of re-ventilation, and also from normoxic controls. The CA immunoreactivity (IR) of all the isoforms studied was weak in the controls, apart from staining of a few oligodendrocytes in the subcortical white matter, some astrocytes in the superficial layer of the cerebral cortex, the cerebellar Purkinje cells and the retinal Müller cells that possessed moderate CA-II IR. However, asphyxia induced a marked increase in the CA IR of all isoforms in all the cerebral regions investigated and the retina after 4 h of survival. The pyramidal cells of the frontal cortex and hippocampus displayed the most conspicuous increase in CA IR. Immunoblotting confirmed increased levels of all the CA isoenzymes. We conclude that raised CA levels after asphyxia may contribute to the compensatory mechanisms that protect against the pathological changes in the neonatal CNS.