László Módis

Publications of László Módis

• Evaluation of Tear Osmolarity in Non-Sjögren and Sjögren Syndrome Dry Eye Patients With the TearLab System.

  Authors: Eszter Szalai, András Berta, Zoltán Szekanecz, Gabriella Szûcs, László Módis

  Cornea. 05/2012;

  PURPOSE: To evaluate tear osmolarity with the recently introduced TearLab system (TearLab Corporation, San Diego, CA) in patients with non-Sjögren syndrome dry eye (NSSDE) and Sjögren syndrome dryPURPOSE: To evaluate tear osmolarity with the recently introduced TearLab system (TearLab Corporation, San Diego, CA) in patients with non-Sjögren syndrome dry eye (NSSDE) and Sjögren syndrome dry eye (SSDE), and in healthy subjects, and to compare the results with those from classical dry eye tests. METHODS: Thirty-nine eyes of 21 patients with NSSDE, 39 eyes of 20 patients with SSDE, and 44 eyes of 22 healthy individuals were included in the study. Tear osmolarity was measured with the TearLab system, lid-parallel conjunctival folds score was examined with the slit lamp, and then the classical diagnostic tests such as Schirmer I test, tear film break-up time, and corneal staining were carried out, followed by the examination of meibomian glands and corneal transparency. RESULTS: Mean tear osmolarity was 296.77 ± 16.48 mOsm/L in NSSDE (15% abnormal), 303.36 ± 17.22 mOsm/L in SSDE (23% abnormal), and 303.52 ± 12.92 mOsm/L in the control group (16% abnormal; P = 0.018, Kruskal-Wallis). Schirmer test, corneal staining, tear film break-up time, and meibomian gland status were significantly different in the 2 patient groups when compared with those in the control group (P < 0.0001). In the control and SSDE groups, no significant correlation was disclosed between tear osmolarity and any of the dry eye tests performed. CONCLUSIONS: Tear hyperosmolarity is considered a key factor that leads to dry eye symptoms and to the progression of clinical signs. Osmolarity measurements with the TearLab system disclosed no ability to distinguish between healthy individuals and patients with dry eye. This suggests that the TearLab device should not be used alone but in combination with classical dry eye tests.

• Reliability and repeatability of swept-source Fourier-domain optical coherence tomography and Scheimpflug imaging in keratoconus.

  Authors: Eszter Szalai, András Berta, Ziad Hassan, László Módis

  Journal of cataract and refractive surgery. 03/2012; 38(3):485-94.

  To evaluate the repeatability and reliability of a recently introduced swept-source Fourier-domain anterior segment optical coherence tomography (AS-OCT) system and a high-resolution ScheimpflugTo evaluate the repeatability and reliability of a recently introduced swept-source Fourier-domain anterior segment optical coherence tomography (AS-OCT) system and a high-resolution Scheimpflug camera and to assess the agreement between the 2 instruments when measuring healthy eyes and eyes with keratoconus. Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary. Evaluation of diagnostic test or technology. Three consecutive series of anterior segment images were taken with AS-OCT (Casia SS-1000) followed by rotating Scheimpflug imaging (Pentacam high resolution). Axial keratometry in the steep and flat meridians and astigmatism values were recorded. Pachymetry in the apex, center, and the thinnest position and anterior chamber depth (ACD) measurements were also taken. This study enrolled 57 healthy volunteers (57 eyes) and 56 patients (84 eyes) with keratoconus. Significant difference was found in all measured anterior segment parameters between normal eyes and keratoconic eyes (P<.05). In keratoconic eyes, the difference between repeated measurements was less with AS-OCT than with Scheimpflug imaging in every keratometry and astigmatism value, in apical thickness, and in ACD. For keratometry, the thinnest and central pachymetry measurement repeatability was better in healthy eyes than in keratoconic eyes with both instruments. In general, the mean difference between AS-OCT and Scheimpflug imaging was higher in cases of keratoconus. Significant differences in keratometry, pachymetry, and ACD results were found between AS-OCT and Scheimpflug imaging. However, the repeatability of the measurements was comparable. No author has a financial or proprietary interest in any material or method mentioned.

• Keratometry evaluations with the Pentacam high resolution in comparison with the automated keratometry and conventional corneal topography.

  Authors: László Módis, Eszter Szalai, Bence Kolozsvári, Gábor Németh, Attila Vajas, András Berta

  Cornea. 11/2011; 31(1):36-41.

  To determine the reliability and repeatability of keratometry (K) measurements obtained with the Pentacam high resolution (HR), automated keratometry, and corneal topography systems. The right eyesTo determine the reliability and repeatability of keratometry (K) measurements obtained with the Pentacam high resolution (HR), automated keratometry, and corneal topography systems. The right eyes of 46 healthy subjects were examined prospectively. Keratometry measurements in the flat (Kf) and steep (Ks) meridians were taken by 2 independent investigators with the Pentacam HR (Oculus, Wetzlar, Germany) followed by automated keratorefractometry (KR-8100; Topcon, Tokyo, Japan), and corneal topography (TMS-4; Tomey, Erlangen, Germany). The mean K readings of the Pentacam HR, automated keratometry, and corneal topography were 43.40/43.34 diopter (D), 43.99/43.98 D, and 43.80/43.83 D, respectively. The difference between the values was statistically significant (P < 0.0001, repeated measures analysis of variance). Strong significant correlation was observed between the Pentacam HR and keratometry (Kf: r = 0.952/0.954; Ks: r = 0.845, Spearman rank test), and Pentacam HR and corneal topography (Kf: r = 0.933/0.930; Ks: r = 0.838/0.829) (P < 0.0001). No significant difference was presented between the 2 investigators for any of the instruments (P = 0.215-0.983). Moreover, high correlation was found between the K readings of the observers (interoperator intraclass correlation coefficients ranged from 0.95 to 0.99). The Pentacam HR provided reliable K measurements in clinical practice in comparison with an automated keratometer and a corneal topographer. Based on the results, for patient follow-up, one keratometry device is recommended.

• Corneal transplantation in Hungary (1946-2009).

  Authors: László Módis, Eszter Szalai, Andrea Facskó, Mariann Fodor, Timea Komár, András Berta

  Clinical & experimental ophthalmology. 08/2011; 39(6):520-5.

  To identify changing trends in indications for corneal transplantation in Debrecen, Hungary over the past 64 years. Retrospective study, at the Department of Ophthalmology, University of Debrecen,To identify changing trends in indications for corneal transplantation in Debrecen, Hungary over the past 64 years. Retrospective study, at the Department of Ophthalmology, University of Debrecen, Hungary. Four thousand seven hundred and seventy-eight patients who underwent keratoplasty. The analysis was based on medical charts, surgical descriptions and eye bank records. Keratoplasty indications between January 1946 and December 2009. For an easier overview, the 64-year interval was divided into seven time periods (1946-1955, I; 1956-1965, II; 1966-1975, III; 1976-1985, IV; 1986-1995, V; 1996-2005, VI; 2006-2009, VII). Over the 64 years, clinical indications for keratoplasty were corneal scarring (24.9%), regraft (18.6%), keratoconus (18.6%), pseudophakic/aphakic corneal oedema (12%), stromal corneal dystrophies (6%), non-infectious keratitis (4.7%), chemical injuries (3.3%), corneal degenerations (3%), mechanical trauma (1.7%), infectious keratitis (1.4%), endothelial corneal dystrophies (1.3%) and others (4.5%). During periods I-IV, corneal scarring was the most common indication for corneal transplantation. In period V, corneal ectasia became the leading clinical indication. Regraft was the most frequent indication in period VI. In the most recent years, an emerging tendency in pseudophakic/aphakic corneal oedema as the indication for keratoplasty was observed. In Hungary, the number of grafts has increased greatly in the past 64 years, the transplantation rates are similar to those of industrial countries. Indications for corneal transplantation have changed considerably over the last half decade from corneal scarring to corneal ectasia, regraft and pseudophakic/aphakic corneal oedema.

• Evaluation of the corneal endothelium using noncontact and contact specular microscopy.

  Authors: Eszter Szalai, Gábor Németh, András Berta, László Módis

  Cornea. 05/2011; 30(5):567-70.

  To determine the difference between the endothelial cell density (ECD) and the morphologic measurements assessed with a recently developed noncontact specular microscope compared with a contactTo determine the difference between the endothelial cell density (ECD) and the morphologic measurements assessed with a recently developed noncontact specular microscope compared with a contact endothelial microscope. The agreement between the 2 independent operators was also investigated. The central corneal endothelium was examined in the right eyes of 41 healthy individuals using automated image analysis programs without correction for a noncontact specular microscope and a contact specular microscope (EM-3000, EM-1000; Tomey, Tennenlohe, Germany). The evaluated parameters such as ECD,average cell area (AVG), and coefficient of variation of the cell area were determined by 2 operators. Conversion factors were also considered to adjust the ECD values. ECD measurements obtained with the noncontact instrument (2734 ± 287 cells per square millimeter, first operator; 2726 ± 282 cells per square millimeter, second operator) were significantly higher (P < 0.0001) in comparison with the contact microscope (2283 ± 206 cells per square millimeter, first operator; 2274 ± 242 cells per square millimeter, second operator) by both investigators. The contact specular microscope significantly overestimated (P < 0.0001) AVG and coefficient of variation of the cell area values. Statistically significant correlation (P < 0.0001) was detected in ECD (r = 0.77, first operator) and AVG measurements (r = 0.72, first operator) between the 2 endothelial microscopes. Higher degree of agreement between operators was given when using the noncontact specular microscope compared with the contact instrument. The significant differences and the poor agreement between the automated software options disclosed that the 2 instruments cannot be used interchangeably.

• Anterior chamber depth measurements obtained with Pentacam HR® imaging system and conventional A-scan ultrasound.

  Authors: Eszter Szalai, András Berta, Gábor Németh, Ziad Hassan, László Módis

  Ophthalmic surgery, lasers & imaging : the official journal of the International Society for Imaging in the Eye. 02/2011; 42(3):248-53.

  To evaluate the reliability and repeatability of anterior chamber depth (ACD) measurements obtained with the rotating Scheimpflug camera and conventional A-scan ultrasound. The right eyes of 46To evaluate the reliability and repeatability of anterior chamber depth (ACD) measurements obtained with the rotating Scheimpflug camera and conventional A-scan ultrasound. The right eyes of 46 healthy volunteers were examined. ACD was determined first with the Pentacam HR (Oculus, Wetzlar, Germany) and then by ultrasound (AL-2000; Tomey, Tennenlohe, Germany). The mean ACD results were significantly shallower when obtained with the Pentacam HR (Investigator 1: 2.89 ± 0.41 mm; Investigator 2: 2.90 ± 0.41 mm) than with ultrasound (Investigator 1: 3.08 ± 0.43 mm, P < .0001; Investigator 2: 3.00 ± 0.45, P = .0005). Significant and strong correlation was observed between the two techniques (Investigator 1: r = 0.937; Investigator 2: r = 0.913). ACD measurements obtained with the Pentacam HR seemed to be reliable and repeatable when the cornea was optically clear. The significant differences between the Pentacam HR and ultrasound indicate that the two devices should not be used interchangeably for ACD measurements.

• Comparison of anterior chamber depth measurements conducted with Pentacam HR® and IOLMaster®.

  Authors: Gábor Németh, Ziad Hassan, László Módis, Eszter Szalai, Kristof Katona, Andras Berta

  Ophthalmic surgery, lasers & imaging : the official journal of the International Society for Imaging in the Eye. 02/2011; 42(3):144-7.

  Anterior chamber depth (ACD) is an important anterior segment parameter. This study compared ACD measurements conducted with two optical devices in phakic, emmetropic eyes. Eighty-three phakic eyesAnterior chamber depth (ACD) is an important anterior segment parameter. This study compared ACD measurements conducted with two optical devices in phakic, emmetropic eyes. Eighty-three phakic eyes of 44 patients with a mean axial length of 23.06 ± 0.94 mm were enrolled in the study. ACD was measured three times with the Scheimpflug-based Pentacam HR (Oculus, Wetzlar, Germany), then three times with IOLMaster (Carl Zeiss Meditec, Dublin, CA), and data were statistically analyzed. The measurements resulted in a mean ACD of 3.01 ± 0.34 mm with Pentacam HR and 2.95 ± 0.32 mm with IOLMaster. Distribution of data was normal, and no significant difference in ACD values was detected (P = .29) between the two devices. Correlation between ACD measurements was highly significant (r = 0.85; P < .0001). In phakic eyes, ACD measured with Pentacam HR and with IOLMaster showed similar values, and high correlation was observed between these two devices.

• Evaluation of the corneal endothelium in patients with diabetes mellitus type I and II.

  Authors: László Módis, Eszter Szalai, Katalin Kertész, Adám Kemény-Beke, Beáta Kettesy, András Berta

  Histology and histopathology. 12/2010; 25(12):1531-7.

  The aim of the present study is to determine corneal physiology and endothelial morphology after proper image analysis technique in type I and II diabetic patients. The HbA1c level and the grade ofThe aim of the present study is to determine corneal physiology and endothelial morphology after proper image analysis technique in type I and II diabetic patients. The HbA1c level and the grade of retinopathy were also recorded and correlated with the endothelial parameters. 41 eyes of 21 patients with type I and 59 eyes of 30 patients with type II diabetes mellitus (mean age was 40.97 ± 15.46 and 64.36 ± 10.47 years) were examined and compared to age-matched controls. Endothelial cell density (ECD), mean cell area, coefficient of variation of cell area, central corneal thickness, intraocular pressure, and grade of retinopathy were recorded. There was a statistically significant decreased endothelial cell density in type I disease (2428 ± 219 cell/mm2) in comparison with healthy subjects (2495 ± 191 cell/mm2, P=0.02). The diabetic corneas were thicker than normal (P=0.001). The HbA1c level was inversely correlated with the ECD (r=-0.60; P<0.0001) and correlated with the mean endothelial cell area (r=0.60, P<0.0001). Significant correlation was observed between the endothelial morphology and grade of diabetic retinopathy (r=-0.40, ECD; r=0.38, mean cell area; P=0.01 for both). In type II diabetes mellitus no significant difference was found in the evaluated values. The present study disclosed the alteration of the corneal endothelial morphology in type I diabetes mellitus as compared to normal subjects. The results indicated that type I diabetic corneas are more susceptible to environmental changes than type II corneas.

• Reliability of the corneal thickness measurements with the Pentacam HR imaging system and ultrasound pachymetry.

  Authors: László Módis, Eszter Szalai, Gábor Németh, András Berta

  Cornea. 12/2010; 30(5):561-6.

  To obtain the central corneal thickness (CCT) of healthy eyes using the rotating Scheimpflug imaging system and compare these results with conventional ultrasound pachymetry values. InteroperatorTo obtain the central corneal thickness (CCT) of healthy eyes using the rotating Scheimpflug imaging system and compare these results with conventional ultrasound pachymetry values. Interoperator reliability and repeatability of the different techniques were also determined. CCT was measured on the right eye of 46 healthy subjects with the Pentacam HR (Pentacam High Resolution; Oculus, Wetzlar, Germany) and contact ultrasound pachymetry (AL-2000; Tomey, Tennenlohe, Germany) by 2 independent investigators. Both observers obtained significantly higher CCT readings with the Pentacam HR imaging system (572 ± 33 and 575 ± 31 μm) than with the ultrasound device (546 ± 27 and 548 ± 28 μm) (P < 0.0001, paired Student t test). Strong and significant correlation was found between the 2 pachymetry techniques regardless of the investigator (r = 0.845 and 0.831, Spearman correlation coefficient) (P < 0.0001). For the Pentacam HR values, statistically significant difference was detected between the observers (P = 0.033). For both pachymetry methods, the degree of agreement between the investigators was reflected by the high interoperator intraclass correlation coefficient value (ICC = 0.96). No significant difference was disclosed between the 3 consecutive readings of either instrument (P > 0.05, analysis of variance). Significant difference in CCT values between the high-resolution Pentacam imaging system and the ultrasound pachymeter suggests that the 2 techniques cannot be used interchangeably in clinical practice.

• Safety and efficacy of etanercept therapy in ankylosing spondylitis patients undergoing phacoemulsification surgery.

  Authors: Adám Kemény-Beke, Zoltán Szekanecz, Sándor Szántó, Nóra Bodnár, László Módis, Rudolf Gesztelyi, Judit Zsuga, Péter Szodoray, András Berta

  Rheumatology (Oxford, England). 11/2010; 49(11):2220-1.

• Factor XIII subunits in human tears; their highly elevated levels following penetrating keratoplasty.

  Authors: Zsuzsanna Z Orosz, Éva Katona, Andrea Facskó, László Módis, László Muszbek, András Berta

  Clinica chimica acta; international journal of clinical chemistry. 10/2010; 412(3-4):271-6.

  As blood coagulation factor XIII (FXIII) is of high importance in wound healing, we determined the concentrations of FXIII A and B subunits (FXIII-A and FXIII-B) and their complex (FXIII-A(2)B(2)) inAs blood coagulation factor XIII (FXIII) is of high importance in wound healing, we determined the concentrations of FXIII A and B subunits (FXIII-A and FXIII-B) and their complex (FXIII-A(2)B(2)) in normal tears and in tears from patients undergoing penetrating keratoplasty (PKP). FXIII complex and subunit concentrations were measured by highly sensitive chemiluminescent ELISAs in tears from 60 healthy volunteers and from 31 patients undergoing corneal transplantation. In non-stimulated tears from healthy volunteers, low but consistent amounts of FXIII-A and FXIII-B (medians: 2.13 μg/L and 7.22 μg/L, respectively) were measured, mostly in non-complexed form. Following stimulation of tear secretion FXIII levels moderately decreased, but if normalized to protein concentration they did not change. One day after PKP FXIII levels became highly elevated, then gradually decreased, but even on day 7 significantly exceeded pre-surgery values. The elevation of tear FXIII levels was significantly higher in PKP patients who later developed neovascularization of donor cornea. FXIII subunits are low concentration components of normal tear. The striking elevation of FXIII subunit and FXIII-A(2)B(2) concentrations after PKP suggests the involvement of FXIII in corneal wound healing. Perioperatively measured high FXIII levels in tears seem to represent a risk of neovascularization.

• [Surgical treatment of ocular surface diseases.]

  Authors: László Módis, Eniko Tóth, András Berta

  Orvosi hetilap. 09/2009; 150(34):1599-606.

  Pathomechanisms leading to ocular surface diseases are difficult to influence, and conservative treatment efforts are inefficient in most cases. However, the development of microsurgical techniques,Pathomechanisms leading to ocular surface diseases are difficult to influence, and conservative treatment efforts are inefficient in most cases. However, the development of microsurgical techniques, the clinical application of molecular biologic methods and the localisation and identification of the function of limbal stem cells made it possible to achieve visual improvement and quality of life in these cases. The authors review the methods of tissue harvesting, cell culturing, transplantation techniques and indications. They provide a detailed survey on the most recommended modern surgical procedures, especially focusing on amniotic membrane and limbal stem cell transplantation.

• [Examination of accommodation in pseudophakic eyes.]

  Authors: Gábor Németh, Alexis Tsorbatzoglou, László Módis, András Berta

  Orvosi hetilap. 06/2009; 150(20):943-8.

  Some patient with monofocal intraocular lens can achieve good near visual acuity with distance correction after cataract surgery. Understanding and measuring this phenomenon also calledSome patient with monofocal intraocular lens can achieve good near visual acuity with distance correction after cataract surgery. Understanding and measuring this phenomenon also called pseudoaccommodation can help to develop new technology to substitute or restore accommodation in pseudophakic eyes. Aim: I. To measure accommodation after cataract surgery. II. To measure anterior chamber depth with Scheimpflug imaging and comparing results with standard, ultrasonic data. III. To compare anterior chamber depth data, repeatability, reproducibility and reliability with a new optical device, the anterior segment optical coherent tomography (Visante (R) OCT) and immersion ultrasound method in phakic eyes. Methods: I. We observed accommodation with defocusing technique, partial coherent interferometry method and measuring anterior chamber depth changing during ciliary muscle blocking. II. We measured anterior chamber depth with Pentacam (R) and data were compared to standard ultrasonic method in phakic and pseudophakic eyes. III. We analyzed anterior chamber depth data, repeatability, reproducibility and reliability obtained by two observers using Visante (R) OCT. Results: I. A total accommodation amplitude of 0,83 D was observed with defocusing technique. Intraocular lens movement were negligible measured by partial coherent interferometry method using physiological accommodation stimulus. Mean movement of intraocular lens was 0.18 mm during blocking of the ciliary muscle. II. Pentacam (R) and ultrasonic device measure the same anterior chamber depth in phakic eyes, but in pseudophakic eyes optical method measures significantly shallower anterior chamber depth. III. Anterior segment optical coherent tomography measures deeper anterior chamber depth than immersion ultrasonic device in phakic eyes. Conclusions: Accomodation and pseudoaccommodation observed in pseudophakic eyes is hard to measure and only parts of this process can be measured with each technique. Anterior chamber depth data varies by the measuring technique. Repeatability, reproducibility and reliability of anterior chamber depth data were better with optical technique.

• Long-Term Kinetics of Cytokine Responses in Human Tears After Penetrating Keratoplasty.

  Authors: Mariann Fodor, Péter Gogolák, Eva Rajnavölgyi, András Berta, László Kardos, László Módis, Andrea Facskó

  Journal of interferon & cytokine research : the official journal of the International Society for Interferon and Cytokine Research. 06/2009;

  This was a kinetic study of inflammatory cytokine levels in postoperative tear samples from penetrating keratoplasty (PKP) patients with or without corneal rejection. In a prospective design,This was a kinetic study of inflammatory cytokine levels in postoperative tear samples from penetrating keratoplasty (PKP) patients with or without corneal rejection. In a prospective design, nonstimulated tears were collected from the affected eyes of 12 patients at regular intervals for 12-14 months following PKP. Nine patients retained clear grafts, whereas three suffered endothelial rejection of the corneal graft within 14 months. The concentrations of the cytokines IL-1beta, IL-6, TNF-alpha, IL-8, IL-10, and IL-12p70 were measured via cytometric bead array technology. The postoperative concentrations of the cytokines in the tears varied among the patients, but exhibited similar alteration patterns in each eye tested. The concentrations of IL-6 and IL-8 were significantly higher (P = 0.009 and P = 0.01, respectively), whereas those of IL-10, TNF-alpha, and IL-12p70 were significantly lower (P = 0.008, P = 0.006, and P = 0.0009, respectively) in the tear samples from the patients with corneal rejection as compared with those with uncomplicated corneal grafts. The ratios IL-6/IL-10 and IL-8/IL-10 were significantly higher (P = 0.0231 and P = 0.015, respectively), and TNF-alpha/IL-10 was significantly lower (P = 0.045) throughout the examination period in the patients with endothelial rejection. The enhanced release of IL-6 and IL-8 into the tears of patients with corneal graft rejection concomitant with decreased concentrations of IL-10, TNF-alpha, and IL-12p70 may possibly serve as an indicator of the rejection process. However, due to the large variation in the cytokine concentrations, the observed changes in tear composition do not categorically predict the final graft outcome.

• Keratoplasty in Hungary.

  Authors: László Módis, Andrea Facskó, András Berta

  Oftalmologia (Bucharest, Romania : 1990). 01/2009; 53(4):123-6.

  The first keratoplasty was performed in Hungary in 1909, but the transplantations were started in large numbers after the Second World War in Debrecen. Since 1992 a National Keratoplasty Register isThe first keratoplasty was performed in Hungary in 1909, but the transplantations were started in large numbers after the Second World War in Debrecen. Since 1992 a National Keratoplasty Register is functioning at the Department of Ophthalmology Debrecen. The present paper gives an overview on the current status of keratoplasty in Hungary based on the data of this Register. The number of corneal transplantations more than doubled in the past two decades. In the past 3 years (2005 to 2008) the number of transplantation seemed to stabilize around a bit more than 700. The ratio of preserved corneas disclosed a constant increase. The turning point was 1997, few years after the establishment of the Debrecen Eye Bank in 1994, when more preserved corneas were transplanted than fresh ones. The law regulating the procurement and the transplantation of corneas in our country is based on presumed consent and explicit objection which is the better type of regulation for the performance of keratoplasties in large numbers. The number of corneal transplantations in Hungary in the past decades was similar to the figures of industrial countries.

• [On Acanthamoeba keratitis.]

  Authors: Beáta Kettesy, Tímea Komár, András Berta, László Módis

  Orvosi hetilap. 11/2008; 149(43):2037-45.

  Acanthamoeba infection is a more and more frequently occuring disorder all over the world and in Hungary as well. Beside diagnostic and therapeutic possibilities it may cause serious visual loss. TheAcanthamoeba infection is a more and more frequently occuring disorder all over the world and in Hungary as well. Beside diagnostic and therapeutic possibilities it may cause serious visual loss. The characteristics of the disease are summarized and presented. It mainly affects people wearing contact lenses with poor hygiene. The subjective signs of the disorder are pain, red eye, tearing and eyelid swelling. In the clinical appearance the ring-shaped ulcer invading the corneal stroma is typical. From differential diagnostic point of view bacterial, fungal, and herpes simplex infection should be excluded. In the diagnosis confocal corneal microscopy and specific laboratory tests are recommended. A wide range of conservative and surgical treatment options are available for treatment. However, early diagnosis and long-lasting adequate therapy are necessary for effective recovery. Prevention is the most important task of contact lens specialists, to inform the patients about adequate hygiene and up-to-date contact lenses and cleaning solutions.

• Hyaluronan accumulates around differentiating neurons in spinal cord of chicken embryos.

  Authors: Zoltán Mészár, Szabolcs Felszeghy, Gábor Veress, Klára Matesz, György Székely, László Módis

  Brain research bulletin. 04/2008; 75(2-4):414-8.

  One major component of the extracellular matrix is hyaluronan (HA) which is thought to play a crucial role in the development of different organs including the central nervous system (CNS). HA isOne major component of the extracellular matrix is hyaluronan (HA) which is thought to play a crucial role in the development of different organs including the central nervous system (CNS). HA is bound by specific receptors, CD44 and RHAMM, depending on cell types of CNS. However, data are lacking on the relation of HA to different cell populations in developing CNS. To provide new data about the co-localization of HA with the various cellular structures of the developing spinal cord, we studied the distribution pattern of hyaluronan in chicken embryos at Hamburger-Hamilton (HH) stages 8-39. A biotinylated HA-binding complex was used in combination with immunohistochemistry for proliferating and differentiating neurons. The intensity of the HA signal was determined by digital densitometry from histological sections. We found three mediolaterally oriented layers in the HA distribution pattern in stage HH23: (1) a moderate HA signal was detected in the ventricular zone; (2) strong HA accumulation was measured around Lim1,2-expressing cells (differentiating neurons) and early MNR2-expressing neurons (early motoneurons), corresponding to the intermediate zone; (3) a strong pericellular HA reaction was found around the neurons of the marginal zone. Interestingly, the peripheral nerves did not show HA signals. These findings suggest a crucial role of HA during neuronal development. We propose that HA may be involved in cell migration and axonal growth in the developing spinal cord.

• The comparative study of two recently developed A-scan devices: determination of central corneal thickness, anterior chamber depth and axial length.

  Authors: Zoltán Sohajda, Júlia Papp, András Berta, László Módis

  Acta ophthalmologica. 03/2008; 86(1):45-8.

  PURPOSE: The clinical use and comparison of two recently developed A-scan ultrasound devices. METHODS: The same investigator determined central corneal thickness (CCT), anterior chamber depth (ACD)PURPOSE: The clinical use and comparison of two recently developed A-scan ultrasound devices. METHODS: The same investigator determined central corneal thickness (CCT), anterior chamber depth (ACD) and axial length (AL) with an OcuScan RxP (Alcon, Forth Worth, Texas, USA) and an AL-2000 (Tomey, Erlangen, Germany) ultrasound device in 80 eyes of 40 patients. The mean patient age was 63.72 years [standard deviation (SD) 18.92]. The patients did not suffer from any systemic or eye disease affecting the anterior and posterior segments of the eye, and their refractive error (spherical and astigmatic) did not exceed +/- 3.0 dioptres. RESULTS: The value of the CCT was 541.55 (SD 34.97) microm with the OcuScan RxP, and 547.46 (SD 35.70) microm with the AL-2000 device (P < 0.001). With respect to the ACD and AL, significantly lower values were obtained with the AL-2000 instrument (P < 0.001). The ACD was 2.92 (SD 0.48) mm with the AL-2000 and 3.07 (SD 0.47) mm with the OcuScan RxP device. The AL was 22.67 (SD 0.84) mm with the AL-2000 and 22.81 (SD 0.87) mm with the OcuScan RxP instrument. However, a positive and significant correlation could be demonstrated between the devices (r = 0.88 CCT, r = 0.86 ACD and r = 0.91 AL; P < 0.001). CONCLUSION: The instruments are reliable in clinical use; however, statistically significant differences were found between the devices. During patient follow-up, the devices cannot simply be used interchangeably.

• The effect of vestibular nerve section on the expression of the hyaluronan in the frog, Rana esculenta.

  Authors: Gábor Halasi, Ervin Wolf, Tímea Bácskai, György Székely, László Módis, Zsuzsa M Szigeti, Zoltán Mészár, Szabolcs Felszeghy, Clara Matesz

  Brain structure & function. 01/2008; 212(3-4):321-34.

  Following postganglionic lesion of the eighth cranial nerve, the changes in the expression of hyaluronan (HA), one of the extracellular matrix macromolecules, were examined in the medial (MVN) andFollowing postganglionic lesion of the eighth cranial nerve, the changes in the expression of hyaluronan (HA), one of the extracellular matrix macromolecules, were examined in the medial (MVN) and lateral (LVN) vestibular nuclei and in the entry or transitional zone (TZ) of the nerve in the frog. HA was detected in different survival times by using a specific biotinylated hyaluronan-binding probe. HA expression was defined by the area-integrated optical density (AIOD), calculated from pixel intensities of digitally captured images. During the first postoperative days the perineuronal net (PN), a HA-rich area around the neurons, was not distinguishable from the surrounding neuropil in the MVN and LVN, characterized by a bilateral drop of AIOD specifically on the operated side. From postoperative day 14 onwards AIOD increased whilst the PN reorganized. In contrast, the AIOD wobbled up and down bilaterally without any trend in the TZ. Statistical analysis indicated that AIOD changes in the structures studied ran parallel bilaterally presumably because of the operation. Our results demonstrated for the first time that (1) the lesion of the eighth cranial nerve is accompanied by the modification of AIOD reflected HA expression in the MVN, LVN and TZ, (2) different tendencies exist in the time course of AIOD in the structures studied and (3) these tendencies are similar on the intact and operated sides. Our findings may suggest an area dependent molecular mechanism of HA in the restoration of vestibular function.

• Oxidative stress-induced poly(ADP-ribosyl)ation in chick limb bud-derived chondrocytes.

  Authors: Róza Zákány, Edina Bakondi, Tamás Juhász, Csaba Matta, Zsolt Szíjgyártó, Katalin Erdélyi, Eva Szabó, László Módis, László Virág, Pál Gergely

  International journal of molecular medicine. 05/2007; 19(4):597-605.

  Oxidative stress has been implicated in the pathogenesis of various diseases affecting chondrogenesis or the function of articular cartilage. DNA damage caused by oxidative stress may trigger theOxidative stress has been implicated in the pathogenesis of various diseases affecting chondrogenesis or the function of articular cartilage. DNA damage caused by oxidative stress may trigger the activation of the nuclear enzyme, poly(ADP-ribose) polymerase-1 (PARP-1) which may contribute to tissue injury. We aimed at investigating the effects of peroxynitrite (100-600 microM) and hydrogen peroxide (0.1-4 mM) on PARP activation and extracellular matrix production of high density micromass cultures (HDC) prepared from chick limb bud mesenchymal cells. We found that both oxidative species strongly inhibited matrix formation of HDCs treated on day 2 but not on day 5. The PARP inhibitor 3-aminobenzamide (3-AB) stimulated matrix production in non-stressed cells and prevented suppressed matrix production in oxidatively stressed cells. Both hydrogen peroxide and peroxynitrite induced PARP activation and poly(ADP-ribose) accumulation. Decreased proliferation, viability and NAD+ content were not or only slightly improved by 3-AB, indicating that 3-AB directly affects matrix formation. In conclusion, oxidative stress stimulates poly(ADP-ribose) metabolism and inhibits extracellular matrix production of HDCs in a PARP-dependent manner. Our findings may have implications for potential therapeutic approaches aimed at restoring the matrix production capacity of chondrogenic cells.