[Allergic and immunopathological diseases of the ocular surface]. / A szemfelszín allergiás és immunpatológiai betegségei.

Allergic and immunopathological diseases of the ocular surface are inflammations that can occur with mild to severe symptoms that cause visual impairment. Allergic inflammations mainly affect the conjunctiva, causing acute and/or chronic conjunctivitis. Several forms are distinguished: seasonal allergic conjunctivitis, vernal conjunctivitis, atopic keratoconjunctivitis, contact allergy, giant papillary conjunctivitis. The most common is the seasonal form, which is linked to seasons. Allergic ocular surface processes require local treatment with artificial tears, anti-allergic eye drops. If complications occur, topical corticosteroid and cyclosporin treatment may be used. Immunopathological inflammations of the ocular surface are associated with systemic diseases. Keratoconjunctivitis sicca, although occurring in the absence of systemic disease, is a common companion of Sjögren's syndrome and collagen diseases. Ocular pemphigoid belongs to the group of mucous membrane pemphigoids. After the initial conjunctivitis symptoms, subconjunctival fibrosis begins, leading to the development of sym- and ankyloblepharon. In the final stage, the ocular surface is covered by scar tissue (ocular cicatricial pemphigoid) which practically results in loss of vision. Peripheral ulcerative keratitis is usually associated with collagen vascular disease, rheumatoid arthritis. A 3-4 mm long, curved infiltration starting near the limbus becomes ulcerated and then perforates, on which the iris may prolapse. First, systemic treatment is required, which is an interdisciplinary task. Topical corticosteroid and cyclosporine eye drops may be administered. In the case of corneal perforation, amniotic membrane transplantation and/or keratoplasty may be performed. Orv Hetil. 2023; 164(43): 1686-1692.

[Corneal transplantation at the beginning of the 21th century]. / Szaruhártya-átültetés a 21. század elején.

Corneal transplantation (keratoplasty) is necessary when various disorders result in corneal opacities with severe visual loss that cannot be treated conservatively, or the regular structure and curvature of the cornea is distorted, and its function is lost. Among human transplantation, keratoplasty is the most successful surgical procedure. In recent decades, penetrating keratoplasties have been increasingly replaced by lamellar techniques, where only the abnormal layer of the cornea is transplanted. The anterior form is deep anterior lamellar keratoplasty (DALK), recommended mainly for keratoconus. The main forms of posterior lamellar keratoplasty are Descemet's stripping automated endothelial keratoplasty (DSAEK) and Descemet's membrane endothelial keratoplasty (DMEK). The indications are bullous keratopathy after cataract surgery with endothelial destruction and Fuchs endothelial dystrophy. Lamellar keratoplasty has several advantages over penetrating surgery. Postoperative visual acuity is better, wound healing, patient rehabilitation are faster and the course of any immune rejection is milder and can be better managed. Orv Hetil. 2023; 164(28): 1087-1093.

Expression Pattern of Tenascin-C, Matrilin-2, and Aggrecan in Diseases Affecting the Corneal Endothelium.

Purpose: The aim of this study was to examine the expression pattern of tenascin-C, matrilin-2, and aggrecan in irreversible corneal endothelial pathology such as pseudophakic bullous keratopathy (PBK) and Fuchs' endothelial corneal dystrophy (FECD), which most frequently require corneal transplantation. Materials and methods: Histological specimens of corneal buttons removed during keratoplasty were investigated in PBK (n = 20) and FECD (n = 9) and compared to healthy control corneas (n = 10). The sections were studied by chromogenic immunohistochemistry (CHR-IHC) and submitted for evaluation by two investigators. Semiquantitative scoring (0 to 3+) was applied according to standardized methods at high magnification (400x). Each layer of the cornea was investigated; in addition, the stroma was subdivided into anterior, middle, and posterior parts for more precise analysis. In case of non-parametric distribution Mann−Whitney test was applied to compare two groups. Kruskal−Wallis and Dunn's multiple comparisons tests have been applied for comparison of the chromogenic IHC signal intensity among corneal layers within the control and patient groups. Differences of p < 0.05 were considered as significant. Results: Significantly elevated tenascin-C immunopositivity was present in the epithelium and every layer of the stroma in both pathologic conditions as compared to normal controls. In addition, also significantly stronger matrilin-2 positivity was detected in the epithelium; however, weaker reaction was present in the endothelium in PBK cases. Minimal, but significantly elevated immunopositivity could be observed in the anterior and posterior stroma in the FECD group. Additionally, minimally, but significantly higher aggrecan immunoreaction was present in the anterior stroma in PBK and in the posterior stroma in both endothelial disorders. All three antibodies disclosed the strongest reaction in the posterior stroma either in PBK or in FECD cases. Conclusions: These extracellular matrix molecules disclosed up to moderate immunopositivity in the corneal layers in varying extents. Through their networking, bridging, and adhesive abilities these proteins are involved in corneal regeneration and tissue reorganization in endothelial dysfunction.

Corneal Densitometry and In Vivo Confocal Microscopy in Patients with Monoclonal Gammopathy-Analysis of 130 Eyes of 65 Subjects.

BACKGROUND: Corneal imaging may support an early diagnosis of monoclonal gammopathy. The goal of our study was to analyze corneal stromal properties using Pentacam and in vivo confocal cornea microscopy (IVCM) in subjects with monoclonal gammopathy. PATIENTS AND METHODS: In our cross-sectional study, patients with monoclonal gammopathy (130 eyes of 65 patients (40.0% males; age 67.65 ± 9.74 years)) and randomly selected individuals of the same age group, without hematological disease (100 eyes of 50 control subjects (40.0% males; age 60.67 ± 15.06 years)) were included. Using Pentacam (Pentacam HR; Oculus GmbH, Wetzlar, Germany), corneal stromal light scattering values were obtained (1) centrally 0-2 mm zone; (2) 2-6 mm zone; (3) 6-10 mm zone; (4) 10-12 mm zone. Using IVCM with Heidelberg Retina Tomograph with Rostock Cornea Module (Heidelberg Engineering, Heidelberg, Germany), the density of hyperreflective keratocytes and the number of hyperreflective spikes per image were manually analyzed, in the stroma. RESULTS: In the first, second and third annular zone, light scattering was significantly higher in subjects with monoclonal gammopathy, than in controls (p ≤ 0.04). The number of hyperreflective keratocytes and hyperreflective spikes per image was significantly higher in stroma of subjects with monoclonal gammopathy (p ≤ 0.012). CONCLUSIONS: Our study confirms that increased corneal light scattering in the central 10 mm annular zone and increased keratocyte hyperreflectivity may give rise to suspicion of monoclonal gammopathy. As corneal light scattering is not increased at the limbal 10-12 mm annular zone in monoclonal gammopathy subjects, our spatial analysis provides evidence against the limbal origin of corneal paraprotein deposition. Using IVCM, stromal hyperreflective spikes may represent specific signs of monoclonal gammopathy.

Central Nervous System Involvement in Primary Sjögren's Syndrome: Narrative Review of MRI Findings.

Central nervous system (CNS) involvement is one of the numerous extraglandular manifestations of primary Sjögren's syndrome (pSS). Moreover, neurological complaints precede the sicca symptoms in 25-60% of the cases. We review the magnetic resonance imaging (MRI) lesions typical for pSS, involving the conventional examination, volumetric and morphometric studies, diffusion tensor imaging (DTI) and resting-state fMRI. The most common radiological lesions in pSS are white matter hyperintensities (WMH), scattered alterations hyperlucent on T2 and FLAIR sequences, typically located periventricularly and subcortically. Cortical atrophy and ventricular dilatation can also occur in pSS. Whilst these conditions are thought to be more common in pSS than healthy controls, DTI and resting-state fMRI alterations demonstrate evident microstructural changes in pSS. As pSS is often accompanied by cognitive symptoms, these MRI alterations are expectedly related to them. This relationship is not clearly delineated in conventional MRI studies, but DTI and resting-state fMRI examinations show more convincing correlations. In conclusion, the CNS manifestations of pSS do not follow a certain pattern. As the link between the MRI lesions and clinical manifestations is not well established, more studies involving larger populations should be performed to elucidate the correlations.

The dualistic role of the purinergic P2Y12-receptor in an in vivo model of Parkinson's disease: Signalling pathway and novel therapeutic targets.

Parkinson's disease (PD) is a chronic, progressive neurodegenerative condition; characterized with the degeneration of the nigrostriatal dopaminergic pathway and neuroinflammation. During PD progression, microglia, the resident immune cells in the central nervous system (CNS) display altered activity, but their role in maintaining PD development has remained unclear to date. The purinergic P2Y12-receptor (P2Y12R), which is expressed on the microglia in the CNS has been shown to regulate microglial activity and responses; however, the function of the P2Y12R in PD is unknown. Here we show that MPTP-induced PD symptoms in mice are associated with marked neuroinflammatory changes and P2Y12R contribute to the activation of microglia and progression of the disease. Surprisingly, while pharmacological or genetic targeting of the P2Y12R augments acute mortality in MPTP-treated mice, these interventions protect against the neurodegenerative cell loss and the development of neuroinflammation in vivo. Pharmacological inhibition of receptors during disease development reverses the symptoms of PD and halts disease progression. We found that P2Y12R regulates ROCK and p38 MAPK activity and control cytokine production. Our principal finding is that the receptor has a dualistic role in PD: functional P2Y12Rs are essential to initiate a protective inflammatory response, since the lack of the receptor leads to reduced survival; however, at later stages of neurodegeneration, P2Y12Rs are apparently responsible for maintaining the activated state of microglia and stimulating pro-inflammatory cytokine response. Understanding protective and detrimental P2Y12R-mediated actions in the CNS may reveal novel approaches to control neuroinflammation and modify disease progression in PD.

Comparison of accuracy of different intraocular lens power calculation methods using artificial intelligence.

PURPOSE: To assess the accuracy of the intraocular lens (IOL) power calculation based on three methods using artificial intelligence (AI) and one formula using no AI. METHODS: During cataract surgery on 114 eyes, one type of IOL was implanted, calculated with the Hill-RBF 2.0 method. The theoretical postoperative refractions were calculated using the Kane and the Pearl-DGS methods and a vergence based formula (Barrett Universal II, BUII). The differences between the manifest and objective postoperative refractions and the predicted refractions were calculated. The percentage of eyes within ±0.5 D and ±1.0 D prediction error (PE), the mean, and the median absolute errors (MAE and MedAE) were also determined. RESULTS: The mean age of the patients was 69.48 years; the axial length was between 21.19 and 25.39 mm. The number of eyes within ±0.5/±1.0 D PE was 96/108 (84.21%/94.73%) using the Hill-RBF 2.0 method, 92/107 (80.70%/93.85%) with the Kane method, 91/107 (79.82%/93.85%) with the Pearl-DGS method, and 91/106 (79.82%/92.98%) with the BUII formula, using subjective refraction. With objective refractometric data, PEs were within ±0.5 D in 88 (77.19%), 83 (72.80%), 82 (71.92%), and 80 (70.17%) cases (Hill-RBF, Kane, Pearl-DGS, BUII, respectively). MAE and MedAE were also best with the Hill-RBF 2.0 method (0.3 D; 0.18 D). CONCLUSION: Better accuracy of PE might be obtained by the Hill-RBF 2.0 method compared with BUII. The Kane and Pearl-DGS methods showed similar accuracy when compared with BUII.

Psychological features of primary Sjögren syndrome / A primer Sjögren-szindróma pszichológiai vonatkozásai.

Összefoglaló. A primer Sjögren-szindróma (pSS) krónikus autoimmun betegség, melynek elsodleges tünetei az exokrin mirigyeket érinto autoimmun folyamat következtében létrejövo szem- és szájszárazság, szisztémás manifesztációi között pedig a leggyakoribbak a szellemi és fizikai fáradtság és az ízületi fájdalmak. A betegség lélektani vonatkozásait nagy érdeklodés övezi; közleményünk a vonatkozó kutatási eredményeket foglalja össze a hátterükben húzódó pszichoneuroimmunmodulációs háttér rövid bemutatásával. A pSS pszichológiai tényezoi közt a legrégebben vizsgáltak a depresszió és a szorongás. Ezek jelentos hatással vannak a betegek életminoségére, jóllétére, kognitív funkcióira, sot a betegség aktivitására is. Bemutatjuk továbbá a stressz és a megküzdési stratégiák jellegzetes mintázatait pSS-ben, amelyek közt a betegségre jellemzo maladaptív stratégiák a legjelentosebbek a patogenezis megértése és a kezelés szempontjából. Ilyenek a tagadás, a hasítás és a helyettesítés. Kitérünk a Sjögren-szindrómát kíséro személyiségjellemzokre is, amely ígéretes terület, de kevés adat áll rendelkezésünkre; az eddigi vizsgálatok alapján a neuroticismus a leginkább pSS-re jellemzo tényezo. A kognitív funkciók érintettségének összefoglalása és az egyéb pszichológiai tényezok (szellemi fáradtság, szexualitás, testképzavar, életminoség) összegzése után egyértelmuen levonható a következtetés, hogy a Sjögren-szindróma nemcsak biológiai, hanem pszichés, pszichoszociális és szociális jelenségszinteken is okoz zavarokat, tüneteket. Ezért rendkívül fontos a betegség biopszichoszociális szemléletu kezelése, a betegek aktív, intencionális részvétele a pSS-sel való megküzdésben. Orv Hetil. 2021; 162(39): 1558-1566. Summary. Primary Sjögren syndrome (pSS) is a chronic, autoimmune disorder. Primary symptoms are ocular and oral dryness as a of an autoimmune process affecting the exocrine glands. The most common systemic manifestations of the disease are mental and physical fatigue and arthralgia. Psychological features of pSS are studied with great interest; the present publication reviews the results of the related investigations alongside with the possible psychoneuroimmunomodulatory background. Among psychological factors in pSS, depression and anxiety have been studied the longest. These impact significantly the quality of life, wellbeing, cognitive functions and disease activity of the patients. Afterwards, we introduce the characteristic patterns of stress and coping mechanisms in pSS, among which maladaptive strategies, typical for the disorder are the most important regarding the pathogenesis and the therapy. These pSS-linked maladaptive strategies are denial, disengagement and focus and venting of emotions. As next, we give a summary about personality characteristics in pSS, which is a promising field to study, and yet very few related data are available; based on them, neuroticism seems to be the most common personality factor in Sjögren's. After summarizing briefly cognitive functions and other psychological features (mental fatigue, sexuality, body image disturbance and quality of life), it is evident that pSS is determined not only by biological but also by psychological, psychosocial and social disturbances. Hence, treating pSS patients with a biopsychosocial perspective is crucial and so is the active and intentional participation of patients in their recovery. Orv Hetil. 2021; 162(39): 1558-1566.

The first local experiences with rheopheresis treatment / A rheopheresiskezeléssel szerzett elso hazai tapasztalatok.

Összefoglaló. Háttér: A rheopheresis egy szelektív, extracorporalis, kettos kaszkádfiltrációs eljárás, mely elozetes plazmaszeparációt követoen egy speciális filter segítségével kivonja a vérplazmából a hiperviszkozitásért felelos komponenseket, úgymint alacsony suruségu lipoprotein, lipoprotein(a), triglicerid, koleszterin, fibrinogén, α2-makroglobulin, Von Willebrand-faktor, immunglobulin-M. Módszer és Betegek: Klinikánkon az elmúlt 5 évben MONET filter alkalmazásával összesen 80 kezelést végeztünk hiperviszkozitással összefüggo, idoskori száraz maculadegeneratióban, diabeteses alsó végtagi fekélyben, illetve neuropathiában. Eredmények: A dolgozatban beszámolunk kedvezo klinikai tapasztalatainkról, a viszkozitás, a klinikai tünetek és az elektroneurográfiai paraméterek tükrében. Orv Hetil. 2021; 162(10): 375-382. BACKGROUND: Rheopheresis is a selective, extracorporeal, double cascade filtration method. After a previous plasma separation, with the help of a special filter it extracts compounds from blood plasma which are responsible for hyperviscosity such as low-density lipoprotein, lipoprotein(a), triglyceride, cholesterine, fibrinogen, α2-macroglobulin, Von Willebrand factor, immunoglobulin M. METHOD AND PATIENTS: In the past 5 years, with the application of MONET filter we performed 80 therapies to treat age-related macula degeneration, diabetic foot ulcers and neuropathy which are complicated with hyperviscosity. RESULTS: The review describes our benefical clinical experiences in consideration of viscosity, clinical symptoms and electroneurography parameters. Orv Hetil. 2021; 162(10): 375-382.

Extracellular matrix changes in corneal opacification vary depending on etiology.

Purpose: The purpose of this study is to examine the expression of tenascin-C and matrilin-2 in three different disorders, which frequently require corneal transplantation. These pathological conditions include bullous keratopathy (BK), Fuchs' endothelial corneal dystrophy (FECD), and corneal scarring in herpetic keratitis. Methods: Histological sections of corneal buttons removed during keratoplasty were analyzed in BK (n = 20), FECD (n = 9), herpetic keratitis (n = 12), and cadaveric control (n = 10) groups with light microscopy following chromogenic immunohistochemistry. The sections were evaluated by three investigators, and semiquantitative scoring (0 to 3+) was applied according to standardized methods at 400X magnification. Each layer of the cornea was investigated; moreover, the stroma was subdivided into subepithelial, middle, and pre-Descemet's membrane areas for more detailed analysis. Results: Excessive epithelial and stromal expression of tenascin-C was identified in all investigated conditions; the results were most pronounced in the pre-Descemet's membrane. Regarding matrilin-2, when examined in BK, there was increased labeling intensity in the epithelium (p<0.001) and stromal layers (p<0.05), and a decrease in the endothelium (p<0.001). In the other investigated conditions, only a low degree of stromal localization (p<0.05) of matrilin-2 was detected. Conclusions: The expression of tenascin-C and matrilin-2 differs when examined in various corneal pathologies resulting in opacification. Both molecules seem to be involved in regeneration and wound healing of the corneal matrix in these diseases.

Comparison of Semi-Quantitative Scoring and Artificial Intelligence Aided Digital Image Analysis of Chromogenic Immunohistochemistry.

Semi-quantitative scoring is a method that is widely used to estimate the quantity of proteins on chromogen-labelled immunohistochemical (IHC) tissue sections. However, it suffers from several disadvantages, including its lack of objectivity and the fact that it is a time-consuming process. Our aim was to test a recently established artificial intelligence (AI)-aided digital image analysis platform, Pathronus, and to compare it to conventional scoring by five observers on chromogenic IHC-stained slides belonging to three experimental groups. Because Pathronus operates on grayscale 0-255 values, we transformed the data to a seven-point scale for use by pathologists and scientists. The accuracy of these methods was evaluated by comparing statistical significance among groups with quantitative fluorescent IHC reference data on subsequent tissue sections. The pairwise inter-rater reliability of the scoring and converted Pathronus data varied from poor to moderate with Cohen's kappa, and overall agreement was poor within every experimental group using Fleiss' kappa. Only the original and converted that were obtained from Pathronus original were able to reproduce the statistical significance among the groups that were determined by the reference method. In this study, we present an AI-aided software that can identify cells of interest, differentiate among organelles, protein specific chromogenic labelling, and nuclear counterstaining after an initial training period, providing a feasible and more accurate alternative to semi-quantitative scoring.

Accuracy of the Hill-radial basis function method and the Barrett Universal II formula.

PURPOSE: The aim was to assess the postoperative results of a biometric method using artificial intelligence (Hill-radial basis function 2.0), and data from a modern formula (Barrett Universal II) and the Sanders-Retzlaff-Kraft/Theoretical formula. METHODS: Phacoemulsification and biconvex intraocular lens implantation were performed in 186 cataractous eyes. The diopters of intraocular lens were established with the Hill-radial basis function method, based on biometric data obtained using the Aladdin device. The required diopters of the intraocular lens were also calculated by the Barrett Universal II formula and with the Sanders-Retzlaff-Kraft/Theoretical formula. The differences between the manifest postoperative refractive errors and the planned refractive errors were calculated, as well as the percentage of eyes within ±0.5 D of the prediction error. The mean- and the median absolute refractive errors were also determined. RESULTS: The mean age of the patients was 70.13 years (SD = 10.67 years), and the mean axial length was 23.47 mm (range = 20.72-28.78 mm). The percentage of eyes within a prediction error of ±0.5 D was 83.62% using the Hill-radial basis function method, 79.66% with the Barrett Universal II formula, and 74.01% in the case of the Sanders-Retzlaff-Kraft/Theoretical formula. The mean- and the median absolute refractive errors were not statistically different. CONCLUSION: Clinical success was the highest when using the biometric method, based on pattern recognition. The results obtained using Barrett Universal II came a close second. Both methods performed better compared to a traditionally used formula.

Lemur Tyrosine Kinase 2 (LMTK2) Level Inversely Correlates with Phospho-Tau in Neuropathological Stages of Alzheimer's Disease.

: Alzheimer's disease (AD) is the most common neurodegenerative dementia. Mapping the pathomechanism and providing novel therapeutic options have paramount significance. Recent studies have proposed the role of LMTK2 in AD. However, its expression pattern and association with the pathognomonic neurofibrillary tangles (NFTs) in different brain regions and neuropathological stages of AD is not clear. We performed chromogenic (CHR) LMTK2 and fluorescent phospho-tau/LMTK2 double-labelling (FDL) immunohistochemistry (IHC) on 10-10 postmortem middle frontal gyrus (MFG) and anterior hippocampus (aHPC) samples with early and late neuropathological Braak tau stages of AD. MFG in early stage was our 'endogenous control' region as it is not affected by NFTs. Semiquantitative CHR-IHC intensity scoring revealed significantly higher (p < 0.001) LMTK2 values in this group compared to NFT-affected regions. FDL-IHC demonstrated LMTK2 predominance in the endogenous control region, while phospho-tau overburden and decreased LMTK2 immunolabelling were detected in NFT-affected groups (aHPC in early and both regions in late stage). Spearman's correlation coefficient showed strong negative correlation between phospho-tau/LMTK2 signals within each group. According to our results, LMTK2 expression is inversely proportionate to the extent of NFT pathology, and decreased LMTK2 level is not a general feature in AD brain, rather it is characteristic of the NFT-affected regions.

Hypothyroidism is Not Associated with Keratoconus Disease: Analysis of 626 Subjects.

PURPOSE: To analyze the association between hypothyroidism and keratoconus, we examined blood thyroid hormone levels and corneal tomographic parameters in healthy subjects and patients with keratoconus. METHODS: We included 626 subjects (304 left eyes, 49%; 431 males, 69%; age 38.4 ± 14.3 y). Patients with keratoconus were from our Homburg Keratoconus Center (HKC) (n = 463); patients with hypothyroidism were from the Department of Internal Medicine of Saarland Medical University, Homburg/Saar, Germany (n = 75); and healthy subjects were from the Department of Ophthalmology of Saarland University Medical Center (n = 88). We included only one randomly selected eye of each subject and the first examination data. EXCLUSION CRITERIA: Previous thyroid medication, previous ocular surgery, and patients with suspected keratoconus (topographic keratoconus classification, [TKC]: 0 < 1). Patient eyes were classified (TKC) with dedicated, instrument-based, keratoconus detection software provided with the Pentacam. TKC = 0 was considered "normal," and TKCs ≥ 1 were considered keratoconus. Subjects were also classified as euthyroid or hypothyroid, based on blood thyroid hormone status (i.e., TSH, FT3, and FT4). A multiple logistic linear regression model was constructed to determine the effects of age (covariate), gender, and hypothyroidism (effect sizes) on "TKC-positive" disease. RESULTS: The significance levels for a constant parameter, sex, thyroid condition, and age were p < 0.0001, p < 0.0001, p < 0.0001, and p=0.003, respectively. The odds ratios for age, sex, and hypothyroidism were 0.98, 3.05, and 3.34, respectively. Male sex and a euthyroid condition had significantly positive, clinically relevant effects, and age had a significantly negative, but clinically irrelevant effect on the estimated TKC index. CONCLUSIONS: Keratoconus appeared to occur more often in patients classified as euthyroid than in patients with hypothyroidism. Thus, hypothyroidism alone could not support the development of keratoconus. Based on these results, it should not be mandatory to screen patients with hypothyroidism for keratoconus or patients with keratoconus for hypothyroidism.

[Corneal disorders in Wilson's disease]. / Cornealis elváltozások Wilson-kórban.

Wilson's disease is an autosomal recessive hereditary metabolic disease with a pathological accumulation of copper in tissues. This study presents the case of a family, where two females and one male from among six siblings had this disease. While in the case of the two women only the liver was affected, the young man presented with both psychiatric and ophthalmic disorders. Modern examination methods (anterior segment optical coherence tomography, corneal topography, endothelial specular microscopy) were used to gather data on the corneal disorder that manifested with the classic Kayser-Fleischer ring. We underline the importance of ophthalmological checkup which may help to diagnose this disease. Orv Hetil. 2019; 160(14): 555-557.

Ocular measurements of a swept-source biometer: Repeatability data and comparison with an optical low-coherence interferometry biometer.

PURPOSE: To assess the repeatability of a swept-source biometer in phakic and pseudophakic patients, including astigmatism analysis, and to compare measurement data with those obtained by an optical low-coherence interferometry method. SETTING: Borsod-Abaúj-Zemplén County Central Hospital and University Teaching Hospital, Miskolc, Hungary. DESIGN: Evaluation of diagnostic technologies. METHODS: One eye of each patient was examined with the Argos and Aladdin devices. With the Argos, three repeated measurements were performed. Biometric parameters and cross-cylinder power vector components of astigmatism were assessed. Descriptive and repeatability data of the Argos were observed, and Bland-Altman plots were created. RESULTS: The study comprised 96 eyes (50 phakic and 46 pseudophakic) of 96 patients (mean age 69.22 years and 71.14 years, respectively). The two devices showed a significant difference regarding astigmatism and corneal diameter in the phakic group (measured larger by Argos, P < .05). In the pseudophakic group, only the corneal diameter data were significantly different (measured larger by Argos, P = .02). No other statistically significant differences were observed in either group. An excellent intraclass correlation coefficient (ICC) was reported on the Argos device in the case of all measured parameters except for the diopter values of astigmatism and the vector values of the astigmatism in the phakic group. In the pseudophakic group, the ICC was moderate in the case of anterior chamber depth (ACD) and good in the case of astigmatism and vectorial data. CONCLUSIONS: The repeatability data regarding the Argos biometer were excellent for all parameters except astigmatism data in both groups and ACD readings in the pseudophakic group. However, only a limited agreement was observed between these devices in both groups.

[Femtosecond laser-assisted keratoplasty]. / Femtoszekundumlézeres keratoplasztika.

INTRODUCTION AND AIM: To present our results on femtosecond laser-assisted penetrating keratoplasty. PATIENTS AND METHOD: Twenty-five eyes of 25 patients underwent surgery with the following indications: pseudophakic bullous keratopathy (n = 10), keratoconus (n = 4), corneal dystrophy (n = 5), corneal scar (n = 4), band keratopathy (n = 2). Trephination of both the donor and recipient corneas were performed with VisuMax femtosecond laser device (Carl Zeiss Meditec AG, Jena, Germany). In each case, trephinaton of the donor tissue was performed first with an artificial anterior chamber (Moria, Antony, France). For the surgical plan and in the postoperative period we obtained different corneal imaging modalities. The corneal power was measured with corneal topography (TMS-4, Tomey, Nürnberg, Germany) and Scheimpflug tomography (Pentacam HR, Oculus, Wetzlar, Germany). The central corneal thickness was evaluated with Pentacam and corneal endothelial cell density was measured with specular microscopy (SP3000P, Topcon, Tokyo, Japan). The corneal structure was imaged with anterior segment optical coherence tomography (Visante, Carl Zeiss Meditec AG). All measurements were performed every 3 months in the first year and yearly thereafter. The follow-up period was 3 years in every case. RESULTS: The corrected decimal visual acuity showed an improvement from a preoperative 0.1 ± 0.1 to a postoperative 0.71 ± 0.18 value at the end of the follow-up period (p = 0.03). All corneal grafts maintained their transparency, there were no immunological rejection during the follow-up. Topographical astigmatism was 4.5 ± 3.1 D in the first month; it showed a decreasing tendency, but there was no significant change in the 3-year period. The mean central corneal thickness changed with 60 µm during the follow-up; there was no significant difference between the first month (564 ± 52 µm) and the third year (596 ± 64 µm) mean pachymetry values (p = 0.1). The mean endothelial cell density decreased first, then remained stable, but did not change significantly from the first (1641 ± 433 cells/mm2) to the last postoperative visit (1220 ± 391 cells/mm2, p = 0.1). CONCLUSIONS: In the case of femtosecond laser-assisted penetrating keratoplasty, trephination of the donor and recipient cornea is performed automatically in a highly precise fashion. The accurate cutting surface provides excellent wound apposition and healing. Both anatomical and functional rehabilitation of patients undergoing surgery are favourable and fast. Orv Hetil. 2018; 159(17): 671-676.

Long-Term Changes in Backscattered Light Measurements in Keratoconus Corneas Treated with Collagen Cross-Linking.

PURPOSE: Our aim was to compare densitometry data between keratoconus and normal corneas and to assess the long-term changes in corneal backscattered light values after corneal collagen cross-linking (CXL) treatment. MATERIAL AND METHODS: Retrospective analysis was performed on 26 eyes of normal patients (age: 32.71 ± 12.68 years) and 39 eyes of keratoconus patients (28.93 ± 7.59 years) using the Pentacam HR corneal densitometry module before CXL and during the postoperative period, which lasted a mean of 2.53 years (range: 1-4 years). Corneal backscattered light values in grey scale unit (GSU) were recorded for the anterior 120 µm, the center layer, and the posterior 60 µm of the cornea in four concentric, central rings. An additional calculation was performed with converting GSU values to GSU/cubic millimeters (mm3) with surface area calculations and using corneal thickness data. RESULTS: Statistically significant differences were observed between normal and keratoconus group densitometry values (in GSU/mm3) in all annuli of the center layer; all, but anterior layer of the 10-12 annuli; all annuli of the total thickness and in all values of the total diameter. In all these cases, the normal cornea showed higher GSU/mm3 values compared to keratoconus corneas (p < 0.05). One month after the CXL treatment, the GSU/mm3 data increased significantly in the anterior, the center, and the posterior zone (p < 0.05), followed by its slow decrease. At the end of the follow-up period, the GSU/mm3 values were significantly higher in all three zones compared to those before the CXL treatment (p < 0.01). CONCLUSION: Densitometry measurements can reflect the changes of optical quality of the cornea. These measurements may play a valuable role in assessing keratoconus and optical changes of the corneas after CXL treatment.

Scanning-slit topography in patients with keratoconus.

AIM: To evaluate the anterior and posterior corneal surfaces using scanning-slit topography and to determine the diagnostic ability of the measured corneal parameters in keratoconus. METHODS: Orbscan II measurements were taken in 39 keratoconic corneas previously diagnosed by corneal topography and in 39 healthy eyes. The central minimum, maximum, and astigmatic simulated keratometry (K) and anterior axial power values were determined. Spherical and cylindrical mean power diopters were obtained at the central and at the steepest point of the cornea both on anterior and on posterior mean power maps. Pachymetry evaluations were taken at the center and paracentrally in the 3 mm zone from the center at a location of every 45 degrees. Receiver operating characteristic (ROC) analysis was used to determine the best cut-off values and to evaluate the utility of the measured parameters in identifying patients with keratoconus. RESULTS: The minimum, maximum and astigmatic simulated K readings were 44.80±3.06 D, 47.17±3.67 D and 2.42±1.84 D respectively in keratoconus patients and these values differed significantly (P<0.0001 for all comparisons) from healthy subjects. For all pachymetry measurements and for anterior and posterior mean power values significant differences were found between the two groups. Moreover, anterior central cylindrical power had the best discrimination ability (area under the ROC curve=0.948). CONCLUSION: The results suggest that scanning-slit topography and pachymetry are accurate methods both for keratoconus screening and for confirmation of the diagnosis.