Evaluation of the Lower Punctum Parameters and Morphology Using Spectral Domain Anterior Segment Optical Coherence Tomography

Abstract

Purpose. To study features of the lower punctum in normal subjects using spectral domain anterior segment optical coherence tomography (SD AS-OCT). Methods. Observational cross-sectional study that included 147 punctae (76 subjects). Punctae were evaluated clinically for appearance, position, and size. AS-OCT was used to evaluate the punctal shape, contents, and junction with the vertical canaliculus. Inner and outer diameters as well as depth were measured. Results. 24 males and 52 females (mean age 44 ± 14.35 y) were included. Lower punctum was perceived by OCT to be an area with an outer diameter (mean 412.16 ± 163 μm), inner diameter (mean 233.67 ± 138.73 μm), and depth (mean 251.7 ± 126.58 μm). The OCT measured outer punctum diameter was significantly less than that measured clinically (P: 0.000). Seven major shapes were identified. The junction with the vertical canaliculus was detectable in 44%. Fluid was detected in 34%, one of which had an air bubble; however, 63% of punctae showed no contents and 4% had debris. Conclusions. AS-OCT can be a useful tool in understanding the anatomy of the punctum and distal lacrimal system as well as tear drainage physiology. Measuring the punctum size may play a role in plugs fitting.

Measurement of lacrimal punctum using spectralis domain anterior optical coherence tomography

“…Recently, Timlin et al. () reported the external punctal size as 646 μ m which was similar to our measurement (Allam & Ahmed ). They defined external punctal diameters as a tangent the highest points on the nasal and temporal punctal walls and vertical canalicular depth as a distance from the tangent created to the bottom of the punctum (Timlin et al.…”

“…Our mean OPD of 617.2 μ m is much larger than the 215–412 μ m cited in a previous studies (Table ) (Wawrzynski et al. ; Allam & Ahmed ; Kamal et al. ) this difference was attributed to the difference in race and age of the participants and the location of the measurement in the studies compared.…”

“…Recent studies showed various punctual depth value measured using OCT from 252 to 890 μ m (Wawrzynski et al. ; Allam & Ahmed ; Kamal et al. ; Timlin et al.…”

Characterizing the lacrimal punctal region using anterior segment optical coherence tomography

“…There have been three prior OCT studies, all with a lower mean diameter (214.71, 247 and 412.16 μ m; Wawrzynski et al. ; Allam & Ahmed ; Kamal et al. ) that is probably attributable to different locations for the measurements.…”

Fourier-Domain OCT Imaging of the Ocular Surface and Tear Film Dynamics: A Review of the State of the Art and an Integrative Model of the Tear Behavior during the Inter-Blink Period and Visual Fixation

“…Similarly, the lacrimal punctal region and the anatomy of vertical canaliculus have been directly imaged and analyzed by commercially available OCT systems and a positive correlation has been found between tear meniscus height and size of the lacrimal punctum ( Figure 10) [89,90]. Moreover, corneo-scleral tissue morphology can also be investigated by detecting the Vogt palisades, the blood and lymph vasculature [91,92].…”