Morphological features of regenerative processes after dacryocystorinostomy with the use of mitomycin C

Abstract

ABSTRACT Purpose To study the morphological features of regenerative processes in dynamics after dacryocystorinostomy (DCR) with the use of Mitomycin C (MMC). Methods The study includes 31 cases. All patients underwent endonasal endoscopic DCR. Group 1 included 16 cases who received MMC injections. Group 2 included 15 cases who were treated with MMC on collagen sponge into the area of formed anastomosis. Biopsies for histological examination were taken on the 2nd, 5th, 7th, 14th, 21st, 28th and 60th days after the surgery. The samples were subjected to histological examination. Results Activated fibroblasts were detected in patients of group 2 on the 5th day after the surgery which became the main cellular elements by the 14th day, and incomplete fibroblast mitoses were observed in group 1 by the 14th day. On the 28th day after the surgery, the transformation of the extracellular matrix into loose connective tissue was determined in patients of group 2, while single cellular elements represented by fibroblasts were preserved in biopsies obtained from patients of group 1. By the 60th day after the surgery, the restoration of a full-fledged epithelial lining was observed in all specimens. Conclusion With the injection of MMC, inhibition of collagenogenesis by depression of extracellular collagen matrix formation, production of abortive mitoses in cells and inhibition of maturation and transformation of fibroblasts occur. The regeneration process takes place after MMC injection under a relative decrease in fibroblast impact.