Abstract
Abstract: :
Purpose: To study the morphology, population, dimensions and the structural complexity of the conjuctival microvilli in dry eye syndrome using transmission electron microscopy. PATIENTS AND Methods: Conjunctival tissue speciments were obtained by bulbar conjunctival biopsy from 8 patients suffering from either primary or secondary Sjögren syndrome and 7 healthy individuals. All 15 speciments were fixed by a standard method and studied by transmission electron microscopy. Evaluation was concentrated on the study of conjuctival microvilli for both groups. RESULTS: 1) Morphology : structural complexity of the microvilli in the Sjögren group, often with duplication or triplication of the villi, was a common observation in all speciments. 2) Population : average number ( ± SD ) of microvilli per 8.3 µm area was significantly lower in the Sjogren group compared to controls ( 19.6 ± 2.5 vs 28 ± 3.4, p <.0001 ). 3) dimensions : The average height ( ± SD ) of the microvilli in dry eyes syndrome was 0,539 ± 0,151 µm and their width was 0,299 ± 0,019 µm ( height / width ratio : 3.65 ). These parameters, differ significantly from the values measured in normal conjunctivas ( height 0,946 ± 0,117 µm, p < .0001, width 0,259 ± 0,029 µm, p = 0.003, height / width ratio : 1.80 ). Conclusions: In the presence of Sjögren syndrome, the following differences in conjunctival microvilli were observed compared to controls : structural complexity, decrease of microvilli population, and reduced height / width ratio, with shortening and widening of the microvilli.
Keywords: microscopy: electron microscopy • comparative anatomy • conjunctiva