Zsuzsanna Szepessy

Photoreceptor distribution in the retinas of subprimate mammals.

Relevant data on the distribution of color cones are summarized, with special emphasis on the marked dorsoventral asymmetries observed in a number of mammalian species. In addition, an overview is given of studies that demonstrate the coexistence of two visual pigments within the same cone cell. The biological significance of these phenomena is discussed in conjunction with comparative immunocytochemical analyses of subprimate retinas. Based on various cone distribution patterns and temporal and spatial visual pigment coexpression, two models of cone photoreceptor differentiation are suggested.

The Effect of Tear Supplementation on Ocular Surface Sensations during the Interblink Interval in Patients with Dry Eye.

Purpose To investigate the characteristics of ocular surface sensations and corneal sensitivity during the interblink interval before and after tear supplementation in dry eye patients. Methods Twenty subjects (41.88±14.37 years) with dry eye symptoms were included in the dry eye group. Fourteen subjects (39.13±11.27 years) without any clinical signs and/or symptoms of dry eye were included in the control group. Tear film dynamics was assessed by non-invasive tear film breakup time (NI-BUT) in parallel with continuous recordings of ocular sensations during forced blinking. Corneal sensitivity to selective stimulation of corneal mechano-, cold and chemical receptors was assessed using a gas esthesiometer. All the measurements were made before and 5 min after saline and hydroxypropyl-guar (HP-guar) drops. Results In dry eye patients the intensity of irritation increased rapidly after the last blink during forced blinking, while in controls there was no alteration in the intensity during the first 10 sec followed by an exponential increase. Irritation scores were significantly higher in dry eye patients throughout the entire interblink interval compared to controls (p<0.004). NI-BUT significantly increased after HP-guar (p = 0.003) but not after saline drops (p = 0.14). In both groups, either after saline or HP-guar the shape of symptom intensity curves remained the same with significantly lower irritation scores (p<0.004), however after HP-guar the decrease was significantly more pronounced (p<0.004). Corneal sensitivity to selective mechanical, cold and chemical stimulation decreased significantly in both groups after HP-guar (p<0.05), but not after saline drops (p>0.05). Conclusion Ocular surface irritation responses due to tear film drying are considerably increased in dry eye patients compared to normal subjects. Although tear supplementation improves the protective tear film layer, and thus reduce unpleasant sensory responses, the rapid rise in discomfort is still maintained and might be responsible for the remaining complaints of dry eye patients despite the treatment.

Macular Changes Correlate with the Degree of Acute Anterior Uveitis in Patients with Spondyloarthropathy

Abstract Purpose: To evaluate the correlation between anterior chamber inflammation and the central foveal thickness of the retina in a homogenous uveitic group (seronegative spondyloarthropathy (subgroup: ankylosing spondylitis)) of patients with the first acute anterior unilateral uveitic attack. Methods: Central foveal thickness (FT) and perifoveal retinal thickness were recorded by optical coherence tomography (Optovue RTVue-100), and the difference between the two eyes was calculated. Statistical analysis was performed by Mathworks Matlab software. Anterior chamber inflammation was measured by laser flare photometry (Kowa FM-600). Results: A statistically significant (p < .05) increase was found in retinal thickness in all OCT subfields in acute anterior uveitic eyes compared to healthy fellow eyes. There was a linear correlation between the degree of inflammation (laser flare photometry values) and central foveal thickness (r = .900, p < .001). Conclusions: We could demonstrate close correlation between macular thickness and inflammation in anterior uveitic patients with spondyloarthropathy.

Intraocular femtosecond laser use in traumatic cataract

Purpose To report the use of femtosecond laser cataract surgery in a traumatic case. Methods A 38-year-old man had a penetrating eye injury while working with wire. The corneal laceration was sutured first. In the postoperative period, cortical cataract appeared in the crystalline lens; therefore, in the second session, cataract surgery was performed using a femtosecond laser system (Alcon-LenSx Lasers Inc.). Results Corneal incisions, an intact 4.5 mm capsulorhexis, and nucleus liquefaction were performed with the femtosecond laser. Corrected distance visual acuity was 0.9 1 month after surgery. Conclusions Femtosecond laser is an effective method in traumatic cataract cases after penetrating eye injury. Corneal incisions, capsulorhexis, and nucleus liquefaction can be performed precisely and safety.

TNAP activity is localized at critical sites of retinal neurotransmission across various vertebrate species.

Evidence is emerging with regard to the role of tissue non-specific alkaline phosphatase (TNAP) in neural functions. As an ectophosphatase, this enzyme might influence neural activity and synaptic transmission in diverse ways. The localization of the enzyme in known neural circuits, such as the retina, might significantly advance an understanding of its role in normal and pathological functioning. However, the presence of TNAP in the retina is scarcely investigated. Our multispecies comparative study (zebrafish, cichlid, frog, chicken, mouse, rat, golden hamster, guinea pig, rabbit, sheep, cat, dog, ferret, squirrel monkey, human) using enzyme histochemistry and Western blots has shown the presence of TNAP activity in the retina of several mammalian species, including humans. Although the TNAP activity pattern varies across species, we have observed the following trends: (1) in all investigated species (except golden hamster), retinal vessels display TNAP activity; (2) TNAP activity consistently occurs in the photoreceptor layer; (3) in majority of the investigated species, marked TNAP activity is present in the outer and inner plexiform layers. In zebrafish, frog, chicken, guinea pig, and rat, TNAP histochemistry has revealed several sublayers of the inner plexiform layer. Frog, golden hamster, guinea pig, mouse, and human retinas possess a subpopulation of amacrine cells positively staining for TNAP activity. The expression of TNAP in critical sites of retinal signal transmission across a wide range of species suggests its fundamental, evolutionally conserved role in vision.

Retinal Sensitivity and Fixation Stability Changes during Repeated Microperimetry

Purpose: To determine and compare the intersession test-retest variability of different microperimetric parameters in healthy volunteers and age-related macular degeneration (AMD) patients by MAIA microperimetry. Methods: Twenty-four eyes of 12 healthy volunteers and 22 eyes of 11 AMD patients were included in this study. Microperimetry examinations were performed three times on each eye of all participants by MAIA microperimetry (CenterVue, Padova, Italy). The second measurement was performed on the same day and the third measurement one week after the first test. Retinal light sensitivity, stability of fixation, and macular integrity were recorded. Statistical analysis was performed by Microsoft Excel software and StatSoft Statistica software. Results: During the examinations, the average threshold had not changed significantly (p>0.475) in time in healthy and AMD patients. Fixation stability was relatively constant (nearly 100%) in healthy subjects as compared to the increase in the improving eye condition of AMD patients (p=0.042). Macular integrity was stable in both groups during the examinations. Conclusion: A learning effect was found in fixation stability of AMD patients by MAIA microperimetry. The improvement in fixation stability might be considered, especially prior to biofeedback training protocols in AMD patients.

Individual Test Point Fluctuations of Macular Sensitivity in Healthy Eyes and Eyes With Age-Related Macular Degeneration Measured With Microperimetry

Purpose To establish fluctuation limits, it was considered that not only overall macular sensitivity but also fluctuations of individual test points in the macula might have clinical value. Methods Three repeated measurements of microperimetry were performed using the Standard Expert test of Macular Integrity Assessment (MAIA) in healthy subjects (N = 12, age = 23.8 ± 1.5 years old) and in patients with age-related macular degeneration (AMD) (N = 11, age = 68.5 ± 7.4 years old). A total of 37 macular points arranged in four concentric rings and in four quadrants were analyzed individually and in groups. Results The data show low fluctuation of macular sensitivity of individual test points in healthy subjects (average = 1.38 ± 0.28 dB) and AMD patients (average = 2.12 ± 0.60 dB). Lower sensitivity points are more related to higher fluctuation than to the distance from the central point. Fixation stability showed no effect on the sensitivity fluctuation. The 95th percentile of the standard deviations of healthy subjects was, on average, 2.7 dB, ranging from 1.2 to 4 dB, depending on the point tested. Conclusion Point analysis and regional analysis might be considered prior to evaluating macular sensitivity fluctuation in order to distinguish between normal variation and a clinical change. Translational Relevance Statistical methods were used to compare repeated microperimetry measurements and to establish fluctuation limits of the macular sensitivity. This analysis could add information regarding the integrity of different macular areas and provide new insights into fixation points prior to the biofeedback fixation training.

Intrasession and Between-Visit Variability of Retinal Vessel Density Values Measured with OCT Angiography in Diabetic Patients

In clinical practice the measurement error of an instrument has special importance in analyzing and interpreting data, and acknowledging limitations. The purpose of this study was to evaluate intrasession and between-visit reproducibility of OCT angiography measurements in diabetic patients. A total of 54 eyes of 27 diabetic patients underwent OCT angiography imaging. Foveal avascular zone (FAZ) area and superficial retinal vessel density (VD) at 3 mm were calculated using the AngioAnalytics software. Three consecutive images were acquired at first visit and one image 1 month later. Intrasession and between-visit reproducibility of parameters were characterized by intraclass correlation coefficient (ICC), coefficient of variation (CV), and coefficient of repeatability (CR) values. We measured excellent (>0.90) ICC values both in intrasession and between-visit comparisons. CV was higher for the FAZ area compared to VD both in intrasession (7.79% vs. 2.87%) and in between-visit (12.33% vs. 2.95%) comparisons. Between-visit CR value for VD was 4.53% (95% CI: 3.72–5.79%). These data suggest that OCT angiography shows excellent repeatability in diabetic patients, indicating that this non-invasive technology might be suitable for longitudinal assessment of microvascular complications.

Diabeteses kisér-károsodás vizsgálata optikai koherencia tomográfián alapuló angiográfiával

Absztrakt: Bevezetes: Az optikai koherencia tomografian alapulo angiografia uj noninvaziv eszkoz, amely lehetőve teszi a retinalis erhalozat vizsgalatat, es segitseget nyujthat a microangiopathiaval jaro szemfeneki betegsegek nyomon koveteseben. Celkitűzes: Diabeteses betegek mindket szemen optikai koherencia tomografias angiografiaval meghatarozni a retinalis kiser-karosodas merteket az altalanos rizikofaktorok fuggvenyeben. Modszer: Optikai koherencia tomografias angiografia soran 36 diabeteses, valamint 45 kontrollszemely mindket szemen meghataroztuk a retinalis erhalozat sűrűseget. Rogzitettuk a magas vernyomast, a diabetes fennallasi idejet, az inzulinkezelest, a HbA1c-szintet, a dyslipidaemia es a diabeteses retinopathia jelenletet, tovabba a szem tengelyhosszat. A rizikofaktoroknak az erhalozat-sűrűsegre es a ket szem kozotti aszimmetriara kifejtett hatasat tobbvaltozos regresszios modellekben vizsgaltuk. Eredmenyek: Diabeteses betegekben a retinalis erhalozat sűrűsege szignifikansan alacsonyabb vo...INTRODUCTION Optical coherence tomography angiography is a non-invasive imaging technique that is able to visualize the different retinal vascular layers using motion contrast to detect blood flow without intravenous dye injection. This method might help to assess microangiopathy in diabetic retinopathy during screening and follow-up. AIM To quantify retinal microvasculature alterations in both eyes of diabetic patients in relation to systemic risk factors using optical coherence tomography angiography. METHOD Both eyes of 36 diabetic patients and 45 individuals without diabetes were examined. Duration of diabetes, insulin therapy, blood pressure, HbA1c, dyslipidemia, axial length and the presence of diabetic retinopathy were recorded. Retinal vessel density was measured by optical coherence tomography angiography. The effect of risk factors on vessel density and between-eye asymmetry was assessed using multivariable regression analysis. RESULTS Vessel density was significantly lower and between-eye difference was significantly higher in diabetic patients compared to controls (p<0.05). Both vessel density and between-eye asymmetry significantly correlated with diabetes duration (p<0.05) after controlling for the effect of risk factors. The between-eye asymmetry in vessel density was significantly higher in patients without clinically detectable diabetic retinopathy compared to control subjects (p<0.001). CONCLUSIONS There is a decrease in retinal vessel density and an increase in between-eye asymmetry in patients with diabetes compared to healthy subjects. By using optical coherence tomography angiography, the detection of these microvascular alterations is possible before clinically detectable diabetic retinopathy and might serve as a useful tool in both screening and timing of treatment. Orv Hetil. 2018; 159(8): 320-326.

Placoid chorioretinopathiák szisztémás fertőzésekben

Absztrakt: Bevezetes es celkitűzes: Szisztemas fertőzesekhez tarsulo placoid chorioretinopathiak ket esetenek bemutatasan keresztul attekinteni a szifilisz es a tuberkulozis szemeszeti tuneteit, terapias lehetősegeit, valamint felhivni a figyelmet az interdiszciplinaris osszefogasra ezen ket betegseg diagnosztikaja es terapiaja teren. Modszer: Első esetunkben a 38 eves, masodik esetunkben a 47 eves nőbeteg bal szem latasromlasa miatt jelentkezett intezmenyunkben. Mindket betegnel a szemfeneki vizsgalat soran macula luteat magaban foglalo, a teljes hatso polust erintő placoid elvaltozas volt lathato. Az első betegnel az infektologiai szerologiai vizsgalat soran Treponema pallidum-IgM-pozitivitas, a masodik beteg eseteben QuantiFERON-pozitivitas igazolodott. Eredmenyek: Az anamnesztikus adatok, a jellegzetes klinikai kep, a pozitiv laboratoriumi vizsgalatok es a terapiara adott kedvező valasz alapjan első esetunkben ocularis szifilisz, masodik esetunkben ocularis tuberkulozis diagnozisat allapitottuk meg. M...