Electron microscopy of human trabecular meshwork in normal and glaucomatous eyes
Abstract
Aqueous humor (AH) outflow resistance is one of the main causes of elevated intraocular pressure (IOP). The ultrastructural trabecular changes are evaluated by means of scanning electron microscopy (SEM) and transmission microscopy (TEM). The trabecular meshwork (TM) consists of the uveal trabecula, the corneoscleral trabecula and the juxtacanalicular tissue, which is attached to the endothelium of the Schlemm’s canal (SC). In primary open-angle glaucoma (POAG), the juxtacanalicular tissue disintegrates, and disorganization of collagen fibers occurs; a homogeneous electron dense material accumulates, which causes obstruction of the SC’s inner wall. It has been suggested that the extracellular matrix of the juxtacanalicular layer plays an important role in AH retention. In patients with pseudoexfoliation glaucoma (PEG), an irregular networklike pseudoexfoliation is formed between the TC fibers, and pigment granules accumulate in the trabecula. In closedangle glaucoma (CAG) the damage occurs in the uveal tract. Also, the role of cell-inflammatory response is significant. Currently, there is no data on what proportion of pathological material in TM can be attributed to electron microscopy artifacts, which appear under extreme conditions. Further research is needed.
About the Authors
S. E. Avetisov
The Scientific Research Institute of Eye Diseases
Russian Federation
Russian Federation
RAS Academician, Professor, Scientific Director
11А Rossolimo st., Moscow, Russian Federation, 119021.
S. Yu. Petrov
The Scientific Research Institute of Eye Diseases
Russian Federation
Russian Federation
Med.Sc.D., Leading Research Associate
11А Rossolimo st., Moscow, Russian Federation, 119021.
M. V. Kravchik
The Scientific Research Institute of Eye Diseases
Russian Federation
Russian Federation
Resident
11А Rossolimo st., Moscow, Russian Federation, 119021.
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Review
For citations:
Avetisov S.E., Petrov S.Yu., Kravchik M.V. Electron microscopy of human trabecular meshwork in normal and glaucomatous eyes. National Journal glaucoma. 2018;17(2):84-89. (In Russ.)
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