Classification of Lacrimal Punctal Stenosis and Its Related Histopathological Feature in Patients with Epiphora

Abstract

Purpose: To evaluate the classification of punctal stenosis based on the shape of the external punctum, clinical characteristics and histopathologic features.

Methods: Patients who experienced tearing and were diagnosed with punctal stenosis were evaluated in this study. Punctal stenosis was classified according to the shape of the lower external punctum, which included membranous type, slit type, horseshoe type, and pinpoint type. Tear meniscus height, 2% fluorescein dye disappearance test and lacrimal pathway irrigation were measured or performed. For treatment, a punctal snip operation and silicone tube placement were performed, and the peripunctal histopathological findings were evaluated.

Results: Punctal stenosis was classified into four types: membranous type (17 eyes, 21.5%), slit type (11 eyes, 13.9%), horseshoe type (25 eyes, 31.6%), and pinpoint type (26 eyes, 32.9%). The tear meniscus was significantly higher, and the 2% fluorescein dye disappeared significantly more slowly in the punctal stenosis group. However, correlation of the tear meniscus height and 2% fluorescein dye disappearance test with the punctum shape was not statistically significant. A history of previous chemotherapy was significantly associated with the occurrence of punctal stenosis, especially the membranous type (p < 0.05). Histopathologic evaluation of the punctum showed differences between the punctum types. Pinpoint puncta exhibited a high density of muscle fibers, while they were faintly visible in the membranous type.

Conclusions: Acquired punctal stenosis has various shapes, and the major types of stenotic puncta exhibited unique histopathologic features. Punctal stenosis and its pathophysiology may be related to multiple factors, such as age and systemic 5-fluorouracil chemotherapy history.

Keywords: Histopathological; Lacrimal apparatus; Lacrimal apparatus diseases.

Fig. 1. The shape of a normal punctum and a stenotic or obstructed punctum. (A) Normal punctual opening, (B) membranous type punctum, (C) slit type punctum, (D) horseshoe type punctum, and (E) pinpoint type punctum (×32).

Fig. 2. Measurement of tear meniscus height with slit lamp. Tear meniscus height (vertical red bar) measured with silt lamp midsection along the lower eyelid directly below the center of the pupil (×16).

Fig. 3. Representative histopathologic findings according to classification of punctal stenosis. (A,B) Faint muscle fiber and abundant connective tissue (black arrow) of membranous type. (C,D) Moderate amount of connective tissue and muscle fibers of slit type. (E,F) Thick mucosal layer with squamous epithelial cells and a moderate amount of connective tissue with inflammation and muscle fibers of horseshoe type. (G,H) Prominent, high-density muscle fibers (white arrow) beneath mucosal layer of pinpoint type. (A,C,E,G) H&E and (B,D,F,H) Masson trichrome. Bar length = 500 µm.