An anterior segment optical coherence tomography study of lower lacrimal punctal stenosis

To assess the lower lacrimal punctal measurements in patients with punctal stenosis versus normal participants using anterior segment optical coherence tomography (AS-OCT). The study included 39 puncti of 21 healthy asymptomatic volunteers attending the general and oculoplastic outpatient clinics (group I: control group) and 30 puncti of 17 patients with a clinical diagnosis of punctal stenosis defined as the punctal diameter less than 0.3 mm measured by slit-lamp biomicroscopy (group II: cases group). The punctal diameter is measured by slit-lamp biomicroscopy in all participants. The external punctal diameter, the inner punctal diameter at three depths (100, 200, and 500 μm), the punctal depth and tear meniscus height were measured using AS-OCT. The internal punctal diameter at 100 μm (239.51±91.14 vs. 168.77±118.07 µm), 200 μm (156.67±75.20 vs. 71.63±76.41 µm), and 500 μm (74.92±60.99 vs. 24.07±34.30 µm) showed statistically significant lower measurements in the cases group compared with the control group. No statistically significant differences were found comparing both groups regarding external punctal diameter otherwise. In the cases group, the punctal diameter measured by slit-lamp biomicroscopy had highly significant statistical evidence of positive correlation with the internal punctal diameter at 200 μm. AS-OCT provides a superior ability to assess the patency of the proximal lacrimal drainage system over the routine slit-lamp examination, especially when the internal punctal diameter is measured at a depth of 200 µm. Further research is required to build consensus on standard terminologies, define the standard measurements, and acquire more extensive normative databases. This would mostly be useful in diagnosis of cases of epiphora with externally nonstenosed puncti and distally patent passages.