[Ocular manifestation of an adult Niemann-Pick disease type B]. / Felnottkori B-típusú Niemann­Pick-betegség szemészeti manifesztációja.

Niemann-Pick disease is a rare, autosomal recessive inherited lysosomal storage disorder. The pathophysiological background for this condition is the deficiency or reduced function of the enzyme sphingomyelinase, as well as a deficiency in the intracellular cholesterol transporter protein. Due to the breakdown defect, sphingomyelin and cholesterol accumulate in the lysosomes of cells. The disease is divided into 5 subtypes (A, A/B, B, C, D). The authors present the case of a 24-year-old young man diagnosed with Niemann-Pick disease type B as a child, focusing on the ophthalmic manifestation of the disease. During the examination of the patient, fundus photographs and fundus autofluorescence imaging were taken, and optical coherence tomography (OCT), optical coherence tomography angiography (OCTA), and visual field (perimetry) examinations were performed. The characteristic macular halo and the cherry-red spot in the fovea were clearly visible during ophthalmoscopy and on the fundus photographs. The OCT images showed focal thickening with high reflectivity in the ganglion cell layer corresponding to the macular halo, and the area of the foveola was spared. With visual field examination, an intact field of vision was found on both eyes. Similar to the presented patient, symptoms in patients with the B subtype are milder, and besides the visceral symptoms, there are no neurological symptoms, and the specific ophthalmic abnormalities do not cause visual impairment. Currently, Niemann-Pick disease is considered a rare disease, and the diagnosis of the patients is often delayed or even missed due to non-specific or mild symptoms. Through consultation between medical specialties, ophthalmological examination can also contribute to the correct diagnosis in cases with mild general symptoms. Timely diagnosis can potentially lead to mitigation of symptoms thanks to the ever-expanding therapeutic options, stabilization of the disease progression, and increase of the patients' life expectancy. Orv Hetil. 2023; 164(46): 1838-1844.

Qualitative and quantitative comparison of two semi-manual retinal vascular density analyzing methods on optical coherence tomography angiography images of healthy individuals.

The aim of this study was to evaluate qualitative and quantitative differences in vascular density analysis of an established and a novel alternative for post-processing on optical coherence tomography angiography (OCTA) images in healthy individuals. OCTA examinations of 38 subjects were performed. After extracting the images, two semi-manual post-processing techniques, the already established Mexican hat filtering (MHF) and an alternative, the Shanbhag thresholding (ST) were applied. We assessed Vessel Density (VD), Skeleton Density (SkD) and Vessel Diameter Index (VDI). We analyzed the results in order to establish similarities or potentially relevant differences. Regarding SkD and VD, MHF generally gave higher values than ST. Simultaneously, mean values were also predominantly higher by MHF; however, standard deviations (SD) were higher by ST (range [mean ± SD]: 0.054 ± 0.038 to 0.134 ± 0.01 and 0.134 ± 0.095 to 0.362 ± 0.028 vs 0.012 ± 0.014 to 0.087 ± 0.03 and 0.039 ± 0.047 to 0.4 ± 0.095 for SkD and VD with MHF vs SkD and VD with ST, respectively). Values of VDI were considerably higher with ST than with MHF, while standard deviation was still significantly higher with ST (range [mean ± SD]: 2.459 ± 0.144 to 2.71 ± 0.084 and 2.983 ± 0.929 to 5.19 ± 1.064 for VDI with MHF and ST, respectively). The noise level reduction of the two methods were almost identical (noise levels: 65.8% with MHT and 65.24% with ST). Using MHF, the vascular network gets more fragmented by an average of 40% compared to ST. Both methods allow the segmentation of the vascular network and the examination of vascular density parameters, but they produce largely inconsistent results. To determine if these inconsistent results are clinically meaningful, and which method is more suitable for clinical use, our results provide further evidence that detailed understanding of the image analysis method is essential for reliable decision making for patients with retinal pathology. For longitudinal monitoring, use of the same image processing method is recommended.

Prevalence of Cilioretinal Arteries: A systematic review and a prospective cross-sectional observational study.

PURPOSE: To review studies focusing on cilioretinal arteries (CLRA) in order to assess the overall prevalence and establish the prevalence of CLRA in a Hungarian Caucasian population. METHODS #1: Systematic literature review of published studies with at least 100 participants. METHODS #2: Non-mydriatic digital colour photographs were taken of 1000 consecutively enrolled healthy Caucasian young adult volunteers. Images were graded by two trained independent observers. Number and location of identified cilioretinal arteries were recorded and statistically analysed. RESULTS #1: Prevalence of CLRA ranges from 6.9% to 49.5%. Detection with fluorescein angiography yields the highest values followed by fundus photography and ophthalmoscopy. Unilateral presence of CLRA is between 70.30% and 93.65%, and temporal location is between 80.77% and 100%. RESULTS #2: We found at least one CLRA in 36.5% of the participants and in 22.75% of all the examined eyes. Cilioretinal arteries (CLRA) were unilateral in 75.34% and bilateral in 24.66%. Of all the identified CLRA, 96.16% were originating from the temporal rim of the optic disc. We identified at least one temporal CLRA supplying the macula in 28% of the participants and 16.95% of the examined eyes. CONCLUSION: Prevalence of CLRA varies depending on identification method. Unilateral presence is unequivocally more frequent similarly to temporal location. From a risk of bias standpoint, high-quality studies are rare. Our data on the distribution pattern of CLRA are similar to that in the international literature. Based on our findings, we assume that slightly more than one-third of the Hungarian Caucasian population has a CLRA.

Identification of microvascular and morphological alterations in eyes with central retinal non-perfusion.

PURPOSE: To evaluate the characteristics and morphological alterations in central retinal ischemia caused by diabetic retinopathy (DR) or retinal vein occlusion (RVO) as seen in optical coherence tomography angiography (OCTA) and their relationship to visual acuity. METHODS: Swept-source optical coherence tomography (SSOCT) and OCTA (Topcon, Triton) data of patients with central involving retinal ischemia were analyzed in this cross-sectional study. The following parameters were evaluated: vessel parameters, foveal avascular zone (FAZ), intraretinal cysts (IRC), microaneurysms (MA), vascular collaterals in the superficial (SCP) and deep plexuses (DCP), hyperreflective foci (HRF), epiretinal membrane (ERM), external limiting membrane (ELM) and ellipsoid zone (EZ) disruption, as well as the disorganization of retinal inner layers (DRIL). Best-corrected visual acuity (BCVA), age, gender, disease duration and ocular history were also recorded. RESULTS: 44 eyes of 44 patients (22 with RVO, 22 with DR) were analyzed. The mean age was 60.55 ± 11.38 years and mean BCVA 0.86 ± 0.36 (Snellen, 6m). No significant difference was found between DR subgroups (non proliferative vs. proliferative). Between RVO subgroups (CRVO vs. BRVO) a significant difference was found in term of collateral vessel of the DCP (p = 0.014). A pooled DR and RVO group were created and compared. Significantly more MAs (p = 0.007) and ERM (p = 0.007) were found in the DR group. Statistically significant negative correlation was demonstrated between FAZ and BCVA (p = 0.45) when analyzing all patients with retinal ischemia. CONCLUSION: This study has shown that the best predictor of visual outcome in center involved ischemic diseases is the size of FAZ. Besides the presence of MAs and ERM, all other OCT and OCTA parameters were present in a similar extent in DR and RVO group despite the completely different disease origins. Our results suggest that as soon as retinal ischemia in the macular region is present, it has a similar appearance and visual outcome independently of the underlying disease.

[Spontaneous visual recovery following a central retinal artery occlusion in a patient with a cilioretinal artery]. / Szemfenéki arteria centralis retinae érelzáródás miatt kialakult hirtelen látásromlás spontán restitúciója cilioretinalis artéria jelenlétében.

Retinal arterial occlusion causes acute, painless vision loss, and it requires immediate emergency care. There are two separate arterial systems (retinal and ciliary) in the retina, and in most cases only the central retinal artery and its branches supply blood to the inner retinal layers. Cilioretinal artery is an anatomical variant, which can also supply blood to the macula from the ciliary arterial system, and in the case of a retinal arterial occlusion, the cilioretinal artery could save central vision. We report a case of a 67-year-old woman who suffered a central retinal arterial occlusion while having a patent cilioretinal artery and she had a complete recovery of her central visual acuity. A series of fundus photography and optical coherence tomography images are presented that were taken during follow-up. The patient's complaints started one week before she presented in our department therefore acute therapy was not given. However, during the course of the follow-up her status gradually improved, and she finally regained 1,0 (20/20) visual acuity. In the presence of a cilioretinal artery following a central retinal arterial occlusion, there is a chance of visual acuity preservation. Orv Hetil. 2019; 160(29): 1146-1152.

[Reproducibility of measurements using the IMEA ADR III critical flicker-fusion frequency measuring device]. / Az IMEA ADR III kritikus fúziós frekvenciavizsgáló eszközzel végzett mérések reprodukálhatóságának vizsgálata.

INTRODUCTION: Measurement of central critical flicker-fusion frequency is a common screening test for eye diseases and additionally it can serve as a useful diagnostic test in numerous neurological and internal diseases. The test might also be used for monitoring purposes. AIM: The aim of the authors was to evaluate a digital central critical flicker-fusion frequency measuring device (IMEA ADR III) in 30 young, healthy Hungarian subjects. METHOD: After a general ophthalmological screening examination, monocular central critical flicker-fusion frequency was measured with four colours. Measurements were carried out on two separate days in three sessions under standardized conditions. Intrasession, intersession and intervisit variabilities, differences in central critical flicker-fusion frequency using the four colours and the effect of certain other influencing factors were determined. RESULTS: There were no statistically significant differences between sessions in the mean and standard deviation of the measurement sets. The central critical flicker-fusion frequency threshold for red colour was significantly lower than for other colours, and the threshold for blue colour was significantly lower than for green. There were no significant differences regarding sex, age, iris colour, and smoking indicating that these factors did not influence the central critical flicker-fusion frequency threshold in these subjects. CONCLUSIONS: Measurement results with the device are reliable and reproducible in healthy, young population in separate sessions.