Biomedical subjects

M R Tetz

Publications and source records attributed to M R Tetz.

39 records · Page 3Linked to original sources

PubMedDate not supplied

Posterior capsule opacification.

A complication of extracapsular cataract extraction with or without posterior chamber intraocular lens (PC-IOL) implantation is posterior capsule opacification. This condition is usually secondary to a proliferation and migration of residual lens epithelial cells. Opacification may be reduced by atraumatic surgery and thorough cortical clean-up. Clinical, pathological and experimental studies have shown that use of hydrodissection, the continuous curvilinear capsulorhexis and specific IOL designs may help reduce the incidence of this complication. Capsular-fixated, one-piece all-polymethylmethacrylate PC-IOLs with a C-shaped loop configuration and a posterior convexity of the optic are effective. Polymethylmethacrylate loops that retain "memory" create a symmetric, radial stretch on the posterior capsule after in-the-bag placement, leading to a more complete contact between the posterior surface of the IOL optic and the taut capsule. This may help form a barrier against central migration of epithelial cells into the visual axis. Various pharmacological and immunological methods are being investigated but conclusive data on these modalities are not yet available.

Cataract↗

PubMedDate not supplied

Age-related changes of the ciliary sulcus: implications for implanting sulcus-fixated lenses.

PURPOSE: To examine age-related anatomical changes of the ciliary sulcus and the implication of these changes for placement of posterior chamber intraocular lenses (IOLs). SETTING: Department of Ophthalmology, University of Heidelberg, Germany. METHODS: In this study, 64 human autopsy eyes from 38 donors were divided by age into six groups from younger than 40 years (Group 1) to 80 years and older (Group 6) in 10 year increments. External diameter, capsular bag size, and lens thickness were determined for each eye. The horizontal and vertical diameters of the ciliary sulcus were measured and histological sectioning, staining, and light microscopy performed. RESULTS: The external diameters of the eyes showed no age correlation; the lenses exhibited the expected increase in thickness with age. The mean vertical diameter of the ciliary sulcus decreased in all age groups from 12.02 mm +/- 0.12 (SD) to 10.71 +/- 0.91 mm and the mean horizontal diameter, from 11.36 +/- 0.24 mm to 10.33 +/- 0.76 mm. Statistical analysis confirmed the overall significance (P < .05) of the differences among age groups. CONCLUSION: The ciliary sulcus became smaller with age. This might affect the size of sulcus-implanted IOLs and should be noted for transsclerally sutured IOLs.

Adult↗

PubMedDate not supplied

[Fuchs' heterochromic cyclitis. Clinico-histopathologic findings of nodular iritis].

BACKGROUND: Despite the fact that in 1906 Fuchs described the first case of Fuchs' heterochromic cyclitis histopathologic reports of this disease are still rare. PATIENT AND METHODS: A clinicopathologic correlation of findings in Fuchs' heterochromic cyclitis is presented. In a patient with a history of Fuchs' heterochromic cyclitis for 15 years a secondary open-angle glaucoma developed. Several operations were performed including intracapsular cataract extraction, goniotrephanation (Elliot) and repeated cyclocryotherapy. The eye finally had to be enucleated because of a painful absolute glaucoma. RESULTS: Clinical hallmarks of Fuchs' heterochromic cyclitis in this patient include cataract formation and secondary open-angle glaucoma. Histology revealed accumulations of mononuclear cells on the surface of the iris and the corneal endothelium, as well as sparse inflammatory cells within the anterior chamber. The trabecular meshwork showed an infiltration of mononuclear inflammatory cells, chiefly lymphocytes and plasma cells. DISCUSSION: Accumulations of mononuclear cells on the surface of the iris, which histopathologically have not been described before, could represent the clinicopathologic correlate of Koeppe and Busacca nodules. Histologically, the cell deposits on the iris were similar to those in the anterior chamber and to larger corneal precipitates. It is supposed that the cells, which originally emigrated from the iris vessels, may form primary cell deposits on the iris surface or endothelium. Such iris precipitates may also be secondarily attracted by the endothelium in whole. An autoimmune-reaction against the corneal endothelium may be the underlying reason.

Adult↗