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M Landesz

Publications and source records attributed to M Landesz.

12 recordsLinked to original sources
PubMed1995

Morphometric analysis of the corneal endothelium with three different specular microscopes.

The morphometry of the central corneal endothelium of 10 eyes in 10 subjects was analyzed with three different specular microscopes. Computer-assisted analysis was performed with only two microscopes (Zeiss and Keeler Konan sp 3300) because the third microscope (Topcon sp 1000) could not be adapted to our computerized system. With this Topcon microscope a grid with standard densities was used to compare the images with, in addition, we also performed manual cell counting on the same Topcon images. The coefficient of variation of the cell analysis of three different images per cornea with the four methods varied between 3.4 and 4.7 percent. One-way analysis of variance showed a significant difference between the Zeiss and the other microscopes. So only the Keeler Konan and the Topcon microscopes could be used interchangeably. The computerized image analysis permitted also an evaluation of the hexagonality. The results of polygonality were not significantly different between the Zeiss and the Keeler Konan. For clinical purposes the Topcon specular microscope is more advantageous than the other two methods, since it is the most rapid way to record and analyze specular images. But for more precise measurements an image processing system is indispensable.

Adult↗
PubMed1995

Comparative study of three semiautomated specular microscopes.

We compared two clinical video-assisted specular microscopes (Zeiss, noncontact, and the wide-field Keeler Konan sp 3300, contact) with an autofocus microscope (Konan noncon Robo-ca sp 8000, noncontact) with built-in analyzing software by studying the morphometry of the central corneal endothelium of 12 eyes in 12 patients. The mean coefficients of variation of the cell size analysis of three successive images per cornea for the three methods were 3.9%, 4.0%, and 2.2%, respectively. One-way analysis of variance showed a significant difference in the mean cell area measured with the three methods; there was no significant difference in the results of hexagonality (pleomorphism) and coefficient of variation (polymegathism). Although each microscope showed a high reproducibility, we do not recommend using the three interchangeably. The Konan noncon Robo-ca sp 8000 specular microscope provides a rapid morphometric endothelial analysis. The Keeler Konan sp 3300 is better for more detailed studies and photography of the corneal endothelium.

Adult↗
PubMed1994

Photorefractive keratectomy to correct astigmatism with myopia or hyperopia.

Excimer laser photorefractive keratectomy as a means to flatten the central cornea has generated considerable interest. With this technique radial symmetric ablations can be performed to correct myopic refractive errors and excise superficial corneal pathology. We developed a technique that uses toric ablation to correct astigmatism. A new mask was designed for the MEL 60 Aesculap-Meditec excimer laser. The mask can be rotated regularly over 360 degrees. By varying the angular distances, the surgeon can increase ablation depth in any desired meridian. As a result, both cylindrical and spherical errors can be corrected in one procedure. Seventy-three eyes with either simple, myopic, mixed, or irregular astigmatism were treated. In each category of astigmatism, the surgery reduced the spherical component as well as the overall mean preoperative cylindrical refraction. Our findings suggest that this technique is a safe and effective procedure for correcting different types of astigmatism.

Adolescent↗
PubMed1993

Negative implant. A retrospective study.

Implantation of a negative power intraocular lens is one of the options for surgical correction of high myopia. We studied 36 eyes with a Fechner Worst Claw Lens, implanted in Groningen between March 1987 and November 1991. The preoperative myopia ranged from -7.00 to -30.00 diopters. Twenty one eyes had a follow up period of more than 12 months. The IOL power was calculated with the van der Heyde method. Correction within 1 diopters of emmetropia has been achieved in 55.5% of the cases. Deviation of more than 2 diopters occurred in 25%. In 24 eyes the best corrected postoperative visual acuity improved. Due to the IOL the retinal image increases in size as compared to spectacle correction. In none of the cases complications were encountered during surgery. In the postoperative period one IOL had to be replaced because of an error made in the calculation of the lens power. In one case endothelial decompensation occurred, probably due to a combination of compulsive eye rubbing and a preexisting cornea guttata. The rim of the IOL optic is the part which is the closet to the endothelium. Our recommendation is that one should avoid indentation of the cornea. No other serious complications occurred in this study.

Adult↗
PubMed1993

Automated video image morphometry of the corneal endothelium.

The central corneal endothelium of 13 eyes in 13 subjects was visualized with a non-contact specular microscope. This report describes the computer-assisted morphometric analysis of enhanced digitized images, using a direct input by means of a frame grabber. The output consisted of mean cell area, cell density, frequency distribution of the individual cell area, and cell polygonality. Results showed that the mean coefficient of variation of images analyzed three times consecutively was 0.95 percent. The cell analysis of three different images of the same subject was accurate, with a mean coefficient of variation of 4.2 percent.

Adult↗
PubMedDate not supplied

Opaque iris claw lens in a phakic eye to correct acquired diplopia.

A 25-year-old man had diplopia caused by abducens nerve paresis on both sides after cranial injury. Because of the patient's reports of persistent diplopia after surgical correction, a specially manufactured, tinted iris claw lens was implanted in the left eye, with the crystalline lens in situ. Fourteen years after surgery, specular microscopy was performed to evaluate the corneal endothelium. The difference in mean endothelial cell density in both eyes was 18.6%. The difference between eyes in polygonality and polymegathism was not significant.

Adult↗
PubMedDate not supplied

Metastatic or dystrophic conjunctival calcification in renal failure?

In renal failure the incidence of pingueculae is significantly higher than in a comparable control group but there is no evidence that the calcific precipitation in renal failure is of a dystrophic nature. The lime salts are not located within the area of elastotic degeneration, a prerequisite for dystrophic degeneration. Moreover there is no association between the magnitude of the conjunctival degeneration and the degree of calcification. This makes it likely that the calcium precipitates represent metastatic calcification even though admittedly support for this assumption is tenuous.

Adult↗
PubMedDate not supplied

Correction of high myopia with the Worst myopia claw intraocular lens.

BACKGROUND: Phakic anterior chamber lenses is one of the modalities used to correct high myopia. We report the initial results of our prospective study on the Worst myopia claw intraocular lens (IOL) that is fixated to the anterior iris. METHODS: We studied 35 eyes in 18 patients with a preoperative myopia ranging from -6.00 to -28.00 diopters (D). The follow up ranged from 6 months (n = 15) to 12 months (n = 20). RESULTS: In 26 (74.3%) eyes, the postoperative spherical equivalent refractive error was within 1.00 D of emmetropia. The mean refraction was stable between 1 to 2 months and 12 months. The mean spectacle-corrected visual acuity improved from 20/50 to 20/40. The straylight measurements did not show a significant increase postoperatively (p = .64). The mean endothelial cell loss was 5.6% (range, +6.3% to -22.6%) at 6 months, and 8.9% (range, +0.77% to -23.5%) at 12 months. We did not encounter major complications. CONCLUSION: Implanting a Worst myopia claw IOL in high myopic eyes resulted in a stable, reasonably accurate refractive outcome. This group of patients will be followed longer because of concern over ocular complications with this technique.

Adolescent↗
PubMedDate not supplied

Long-term results of correction of high myopia with an iris claw phakic intraocular lens.

PURPOSE: Anterior chamber phakic intraocular lenses (PIOLs) are one of the modalities used to correct high myopia. We report the long-term results of our prospective study on the Artisan 5-mm optic myopia lens. METHODS: We studied 67 eyes of 38 consecutive patients with preoperative myopia ranging from -5.38 to -28.00 D. All patients were operated by one surgeon. Mean follow-up was 35 months (24 months in 67 eyes and 36 months in 61 eyes). RESULTS: In 45 eyes (67.2%), postoperative residual refraction was within +/- 1.00 D of emmetropia. The mean refraction was stable statistically during the entire follow-up period. Mean best spectacle-corrected visual acuity improved from 20/40 to 20/32. Mean endothelial cell loss at 6 months was 5.5% (range, -52.4% to +9.3%), at 12 months, 7.21% (range, -53.2% to +20.1%), at 24 months, 9.1% (range -43.6% to +13.6%), and at 36 months, 10.9% (range, -43.0O% to +11.4%). The majority of eyes had an increase in best spectacle-corrected visual acuity; 5 eyes lost best spectacle-corrected visual acuity. We encountered no major complications. CONCLUSION: Implanting the Artisan 5-mm optic myopia lens in high myopic eyes resulted in a stable and accurate refractive outcome. The apparent progressive corneal endothelial cell loss remains a matter of concern.

Adolescent↗
PubMedDate not supplied

Iris-claw phakic intraocular lens for high myopia.

PURPOSE: To evaluate the efficacy, safety, predictability, and stability of implanting a polymethylmethacrylate (PMMA) phakic intraocular lens (PIOL) (the Artisan myopia lens) to correct high myopia. METHODS: An Artisan myopia lens was implanted in 78 consecutive eyes of 49 patients with preoperative myopia that ranged from -6.25 to -28.00 D. Mean patient age was 42.4 years. Mean follow-up was 10.7 months and all patients were followed for at least 6 months; 45 eyes had follow-up of 12 months, and 10 eyes had 24 months. The desired outcome was emmetropia in all eyes except for those eyes with preoperative myopia greater then -23.00 D. RESULTS: Fifty-three eyes (67.9%) had a postoperative refraction at the last follow-up examination within +/-1.00 D of emmetropia, and 39 eyes (50.0%) had a postoperative refraction +/- within 0.50 D of emmetropia. The postoperative refraction remained stable during the entire follow-up period. Mean spectacle-corrected visual acuity improved from 20/32 preoperatively to 20/25 postoperatively. Mean postoperative uncorrected visual acuity was 20/32. There was no significant change in endothelial cell density from baseline. We did not encounter major complications. CONCLUSION: Implantation of the Artisan myopia lens to correct high myopia resulted in a stable and fairly predictable refractive outcome. A significant endothelial cell change was not detected.

Adult↗
PubMedDate not supplied

Phototherapeutic keratectomy in recurrent corneal epithelial erosion.

BACKGROUND: Excimer laser phototherapeutic keratectomy has generated considerable interest in treating superficial corneal and scleral pathology. The excimer laser is also used to treat recurrent corneal epithelial erosions. METHODS: With the MEL 50 Aesculap-Meditec 193-nanometer argon-fluoride excimer laser, we treated 74 eyes of 73 individuals, who suffered from posttraumatic, therapy-resistant, recurrent corneal epithelial erosions. We used the excimer laser in spot-mode under manual guidance. Only in those eyes where the erosion was covered with loose bullous epithelium did we remove the epithelium mechanically prior to surgery. The postoperative follow-up period ranged from 6 months to 4 years. RESULTS: Of the 74 eyes, 55 (74.43%) eyes were recurrence-free. One eye developed superficial haze in the treated area. No other complications occurred. CONCLUSION: Phototherapeutic keratectomy in recurrent epithelial erosions is a promising treatment, especially in recalcitrant cases with the erosion over the entrance pupil. Photoablation allows a fast reepithelialization of the affected area and quick relief for painful symptoms.

Adult↗