Measurement of pupil reactivity using fast pupillometry.

Analysis of human eye pupil reactivity is a very valuable diagnostic method used mainly for evaluation of the condition of the autonomic nervous system and the visual system. The paper presents an experimental pupillometer built in the Institute of Physics of the Wroclaw University of Technology. The apparatus makes it possible to record and analyze pupillary light reflex and spontaneous changes in the pupil diameter during a session in the dark. The detector system used in the pupillometer allows us to record the pupil diameter at a rate of 90 Hz with a linear accuracy of 0.008 mm. In this paper, the proposed detection method, the principle of operation and calibration of the apparatus and the possibilities of the measurement system are presented.

[Iron deposits in cornea in confocal microscope]. / Zlogi zelaza w rogówce w mikroskopie konfokalnym.

PURPOSE: The study aimed to evaluate the iron deposits in corneas in confocal microscope. MATERIAL AND METHODS: The material comprised 16 eyes which underwent photorefractive keratectomy (PRK) procedure. The structure of corneas was evaluated between 3-10 years after PRK. The visual acuity after PRK was the same as the best corrected visual acuity before the procedure. The structure of corneas was evaluated in vivo using scanning slit confocal microscopy. The confocal images of corneas in patients after PRK were compared with confocal corneal images of patients with corneal scars (2 eyes), keratoconus (2 eyes), after radial keratotomy (RK) (2 eyes) and healthy patients. RESULTS: Within the central part of corneal epithelium and anterior part of stroma, the clusters of iron deposits were observed. They were round and produced different shapes. In the paracentral and peripheral part of corneas the subepithelial nerve plexus was detected. Beneath, the pattern of keratocytic nuclei, characteristic for state after PRK, was detected. In patients with corneal scars, keratoconus and after RK, the same clusters of deposits were detected. In cases of corneal scars, additionally high reflectivity of corneal structure was observed. CONCLUSIONS: The iron deposits in corneal structure arise in epithelium and anterior part of corneal stroma. The iron deposits which produce different shapes have no influence on visual acuity.

[Structural changes in the cornea after LASIK-u during the early postoperative period]. / Zmiany struktury istoty wlasciwej rogówki po LASIK-u we wczesnym okresie pooperacyjnym.

PURPOSE: The study aimed to evaluate in vivo the corneal structure after refractive surgery and monitor morphologic and morphometric changes in the post-operative period. MATERIAL AND METHODS: The study included 35 eyes (25 patients) who underwent LASIK correction of myopia. The structure of the cornea was evaluated in vivo using a scanning slit confocal microscope. Each cornea was examined before, 2, 4 and 8 weeks after procedure. The keratocyte density was evaluated morphometrically in the anterior and posterior corneal stroma. RESULTS: Before surgery the keratocyte density in the anterior stroma ranged from 900 to 1200/mm2, while in the posterior stroma it ranged from 600 to 950/mm2. 8 weeks after LASIK the keratocyte density in anterior stroma ranged from 695 to 1048/mm2 and in posterior stroma from 565 to 935/mm2. CONCLUSIONS: After LASIK the keratocyte density decreases in anterior stroma while in posterior stoma it is constant.

[Correction of myopia with LASIK--two year observation]. / Korekcja krótkowzrocznosci metoda LASIK--dwuletnie obserwacje.

PURPOSE: The purpose of this study was to evaluate the clinical results of correction of moderate and high myopia as well as myopic astigmatism with LASIK. MATERIAL AND METHODS: 112 randomly selected eyes (79 patients) were analyzed after LASIK. In this group there were 55 women and 24 men aged 17 to 50 (mean 34.9). The eyes were divided into two groups (the first: between -8.0 D to -14.75 D; the second: between -15.0 D to -23.0 D). The follow-up time was 24 months. The effectiveness of this method was evaluated on the basis of the best visual acuity without correction after LASIK procedure compared to the best visual acuity with correction before LASIK. The course of the healing process, the state of cornea and subjective symptoms were also evaluated. RESULTS: One week after the operation (after LASIK) a statistically significant decrease of mean visual acuity was observed. In group I after 2 weeks the mean visual acuity was in the same range of values compared with the visual acuity before the operation. In the next period no statistically significant were observed differences. In group II after 2, 4, and 12 weeks the mean visual acuity was equalized in comparison with the mean visual acuity before correction. After 6, 12 and 24 months statistically significant improvement of visual acuity was observed. CONCLUSION: On the basis of our own observations we can say that LASIK is an effective and safe method of myopia and myopic astigmatism correction.

[New generation of excimer laser--Asclepion Meditec MEL 70 G-Scan]. / Nowa generacja lasera excimerowego--MEL 70 G-Scan firmy Asclepion-Meditec.

The new Asclepion-Meditec MEL 70 G-Scan represents a breakthrough in surgical application of excimer laser. The laser uses the latest generation of flying spot system which utilizes a SafeScan algorithm (patent pending) to avoid corneal surface irregularities. The system utilizes a Gaussian beam profile. In cases where the cornea has regular surface, the conventional excimer laser PRK or LASIK method will provide good results. If the cornea shows an irregular surface shape, custom-tailored, topography-based ablation, which has been adapted to the corneal irregularity, should provide better results. Asclepion-Meditec have added a TSA (Tissue saving Algorithm) module to TOSCA (Topography Supported Customized Ablations) software for carrying out topography-guided corrections. This module automatically minimises the tissue removal when calculating the correction program. MEL 70 G-Scan allows to treat all forms of refractive errors, myopia and myopic astigmatism -24 D sph, -12 D cyl, hyperopia and hyperopic astigmatism +16 D sph, +8 D cyl, mixtus and irregular astigmatism.

[Use of AutoTopograf TMS-3 keratoconus screening program for keratoconus detection]. / Wykorzystanie programu przesiewowego AutoTopografu TMS-3 do detekcji stozka rogówki.

PURPOSE: The purpose of this study was to investigate sensitivity of Klyce-Maeda and Smolek-Klyce methods in detection of early or suspect keratoconus by using AutoTopographer TMS-3 (Tomey). MATERIAL AND METHODS: At the First Department and Clinique of Ophthalmology, Silesian Medical School in Katowice, 175 eyes underwent ophthalmological examinations. There were 67 eyes with irregular astigmatism, 39 eyes with PRK decentration and 69 eyes with early or suspected keratoconus. The procedure was performed with the TMS-3 AutoTopographer (Tomey). During the study we investigated index definitions included in Keratoconus Screening Program. RESULTS: The examination showed the false positive results: in irregular astigmatism (KSI index in 31.3%, KPI index in 10.4%), in PRK decentration (KSI and KPS index in 18%). The results of analysis of keratoconus detection by Keratoconus Screening Program in early or suspected keratoconus were false negative (it means there were no keratoconus symptoms) in KCI index--24.6%, in KSI index--11.6% and KPI index--21.7%. CONCLUSION: To sum up, we can say that Keratoconus Screening Program is a good program for confirming diagnosis of early keratoconus in 80%, but it has to be assisted by a clinical examination.

[Procedure for keratoconus detection according to the Rabinowitz-Rasheed method--personal experience]. / Procedura detekcji stozka rogówki wedlug Rabinowitza-Rasheeda--doswiadczenia wlasne.

PURPOSE: The purpose of this study was to investigate sensitivity of KISA% index to compare with Klyce-Maeda and Smolek-Klyce methods in detection of early or suspected keratoconus by using AutoTopographer TMS-3 (Tomey). MATERIAL AND METHODS: At the First Department and Clinique of Ophthalmology, Silesian Medical School in Katowice, 69 eyes underwent ophthalmological examinations in patients, who did not wear contact lenses at least for 6 weeks before examination. The procedure was performed with the TMS-3 AutoTopographer (Tomey). During the study we investigated index definitions included in Keratoconus Screening Program. RESULTS: The examination showed the false negative results in 29% patients with early or suspected keratoconus. Using KISA% index we detected false negative results in 5.8% patients with early or suspected keratoconus. CONCLUSION: To sum up, we can say that the KISA% index is highly sensitive and specific for diagnosing keratoconus, more useful than Klyce-Maeda and Smolek-Klyce methods. This method can be used by users of all types of videokeratoscopes.

[Eight year results of excimer laser correction for irregular astigmatism by linear excimer laser photoablations of the cornea in cases of keratoconus]. / Osmioletnie wyniki korekcji astygmatyzmu nieregularnego metoda linijnych fotoablacji laserem excimerowym w przypadkach stozka rogówki.

PURPOSE: The purpose of this study was to evaluate changes of the corneal curvature as a result of linear incisions with excimer laser and also to evaluate durability of the achieved effect, including the changes in visual acuity, topographic maps of the corneal curvature and keratometric changes at the location of keratoconus 2, 4, 8, 16, 24 weeks postoperatively. MATERIAL AND METHODS: At the First Department and Clinic of Ophthalmology, Silesian Medical School in Katowice, 294 patients went through ophthalmological examinations. 164 patients (187 eyes) with the III degree of keratoconus according to the Amsler scale, including 69 women (77 eyes) and 95 men (110 eyes), were classified for the excimer laser surgery with the method of linear, corneal incisions with MEL-60 (Aesculap-Meditec). The eyes did not tolerate contact lenses at all or because of peripheral location of the keratoconus. The patients were from 16 to 60 years of age (the mean age was 27.9 years). RESULTS: According to the statistical results, there were no difference between the effects of treatment between men and women. Correlation between the results of the surgery and the patients age showed that the latter did not have any effect on the final result. Lack of correlation between the height of the absolute corneal curvature at the keratoconus and the achieved change after the surgery was reported, thus changes of the corneal curvature parameters do not depend on its parameters before the surgical procedure. Absolute visual acuity of patients was improving and reached maximally 0.252 of the unit. As a result of the single surgery, the maximum change of keratometric values was 4.949 D, and the minimum was 3.611 D. In the case of the secondary surgery, the maximum keratometric value at the axis of the incision was 8.55 D and the minimum one was 7.101 D. CONCLUSION: To sum up, we can say that the favourable effect of decreasing the irregular corneal astigmatism with the method of linear laser fotoablations was maintained throughout the whole observation period, which allowed to shift in time planned corneal transplantation.

[Correction of irregular astigmatism using excimer laser MEL 70 G-Scan with the TOSCA program--introductory report]. / Korekcja niezbornosci nieregularnej przy uzyciu lasera excimerowego MEL 70 G-Scan z programem TOSCA--doniesienie wstepne.

PURPOSE: The purpose of this study was to evaluate changes of the corneal curvature as a result of excimer laser ablation using the TOSCA and TSA system. MATERIAL AND METHODS: At the First Department and Clinic of Ophthalmology, Silesian Medical School in Katowice, 8 patients (8 eyes) with the II and III degree of keratoconus according to the Amsler scale, including 4 women (4 eyes) and 4 men (4 eyes), were classified for the excimer laser surgery with the method of PRK with TOSCA program and TSA system with MEL 70 G-Scan (Asclepion-Meditec). The eyes did not tolerate contact lenses at all or because of peripheral location of the keratoconus. The patients were from 18 to 42 years of age (the mean age was 25.8 years). The observation period was 4 weeks. RESULTS: According to the statistical results lack of correlation between the height of the absolute corneal curvature at the keratoconus and the achieved change after the surgery was reported. The improvement of patients absolute visual acuity was improving and reached 0.2 of the unit. CONCLUSION: To sum up, we can say that the favourable effect of decreasing the irregular corneal astigmatism with the method of laser fotoablations with topography-controlled system was maintained throughout the whole observation period, which probably allowed to shift in time planned corneal transplantation.

[The alterations in corneal structure at III/IV stage of keratoconus by means of confocal microscopy and ultrasound biomicroscopy before penetrating keratoplasty]. / Zmiany struktury rogówki w III/IV stopniu stozka rogówki obrazowane badaniami mikroskopii konfokalnej i biomikroskopii ultradzwiekowej przed przeszczepem drazacym.

PURPOSE: The aim of the study was in-real time observation and morphological evaluation of the human corneas at III/IV stage of keratoconus, using the scanning slit confocal microscope Confoscan P4 and ultrasound biomicroscopy--UBM. MATERIAL AND METHODS: The patients with keratoconus were examined according to the Amsler scale. The material consisted of 12 corneas of 11 patients (8 men, 3 women), where assessment of the corneal structure was performed with the confocal microscope ConfoScan P4 (Tomey) and ultrasound biomicroscopy--UBM Model 840 (Humphrey Instruments). The comparison of different corneal regions (central and peripheral) was evaluated. RESULTS: The confocal microscopy and UBM revealed thinning of the layers of the corneal structure and pathological changes in the central area, especially at IV stage of keratoconus. The desquamating superficial cells were elongated, arranged around the apex of the cornea. Below the Bowman's membrane a considerable disarrangement of collagen fibers reflected by bright background illumination was observed. In the posterior part of the stroma the folds were detected. The examination of the cornea showed thickening in the peripheral part, central detachment of the Descemet's membrane and the endothelium from the posterior surface of the cornea. The thickness of the cornea varied from 0.201 to 0.384 mm in the central part and 0.675 to 0.740 mm in the peripheral area. CONCLUSION: Confocal scanning microscopy combined with ultrasound biomicroscopy enables the cornea to be examined in vivo. It can be used to localize pathological changes in individual corneal layers and to assess their extent.