Secondary Acquired Nasolacrimal Duct Obstruction as a Specific Complication of Treatment With Radioactive Iodine (Morphological Study).

Abstract

To conduct a morphological study of structural changes in the nasolacrimal duct in secondary acquired nasolacrimal duct obstruction (SALDO) as a result of treatment with radioiodine. Twenty patients (20 cases) were involved: 10 cases with secondary acquired nasolacrimal duct obstruction at Hasner's valve level due to the treatment with radioiodine (group 1) and 10 cases with primary acquired nasolacrimal duct obstruction (group 2). During surgery, a biopsy of nasolacrimal duct tissue from Hasner's valve area was taken. A morphological study was performed using semi-fine sections technique. Patients of group 1 showed the following: desquamation of columnar epithelium, pinpoint ulceration of nasolacrimal duct wall, collapse of a significant part of the capillary bed, and absence of blood cells in their lumen. State of secretory cells of mucous glands varied from necrobiotic to the different stages of dystrophic, decreased lumens of acini with abundant microvesicles in cell cytoplasm were revealed. A specific sign noted in patients of group 2 was mixed inflammatory infiltration of the mucosa of the nasolacrimal duct. The picture corresponds to the exacerbation of a chronic inflammatory process. Changes revealed in patients of group 1 include desquamation of nasolacrimal duct epithelium, mucous gland lesion, and moderate fibrosis that indicate a probable primary character of the lesion. In patients of group 2, fibrotic changes were more significant and were due to a chronic inflammatory process. Thus, secondary acquired nasolacrimal duct obstruction after treatment with radioactive iodine has a specific pathogenesis and should be classified as a separate nosological form.