Ocular Surface Changes Differ in Upper vs. Lower Lacrimal Duct Obstruction

Upper LDO was linked to more severe ocular surface and lid margin damage but relatively preserved tear film stability, while lower LDO was characterized by more profound tear film instability and less severe staining. Researchers say management should be phenotype-specific: surgery for upper LDO requires caution, while prompt intervention is recommended for lower LDO presenting with epiphora. Photo: Türk A, et al. Turk J Ophthalmol. 2019;49(1):50-2. Click image to enlarge. Previous studies have shown that lacrimal duct obstruction (LDO) can impact the stability of the tear film, which recently prompted researchers to explore the correlation between ocular surface parameters and location of LDO. They found that upper LDO is linked to more severe ocular surface and lid margin damage but relatively preserved tear film stability, while lower LDO is characterized by more profound tear film instability. These findings suggest that upper vs. lower LDO have divergent patho­physiological mechanisms, possibly from site-specific inflammatory patterns and differential disruption of neuroregulatory feedback. The study, published earlier this week in BMC Ophthalmology, included 74 patients (94 eyes) diagnosed with LDO over a two-year period. Affected eyes were classified into an upper LDO group (29 eyes: obstruction in upper, lower or common canaliculus) and a lower LDO group (65 eyes: obstruction in lacrimal sac or nasolacrimal duct). Various ocular surface parameters were collected, including mean non-invasive tear breakup time (NIBUT), Sjögren’s International Collaborative Clinical Alliance Ocular Staining Score (SICCA OSS) and Korb scores for the lid wiper. Based on cutoff values, NIBUT was categorized into three intervals: ≤5s (NIBUT1), 5s to 10s (NIBUT2) and >10s (NIBUT3). Similarly, SICCA OSS was graded as SICCA.1 (≤1 point), SICCA.2 (1 to 2 points) or SICCA.3 (>2 points). The Korb score was also three-tiered: Korb1 (≤1 point), Korb2 (1 to 2 points) and Korb3 (>2 points). For guidance on managing patients with lacrimal gland obstruction, see this recent feature. Significant differences in ocular parameters were found between the two groups. Upper LDO was linked to more severe ocular surface and lid margin damage (higher Korb3 and SICCA.2 scores) and relatively preserved tear film stability (fewer NIBUT1 cases). Lower LDO was linked to more profound tear film stability (higher proportion in NIBUT1 group) and less severe staining (higher proportion in SICCA.1 group).Upper LDO likely incites a localized inflammatory response near the lid margin and lacrimal canaliculus, which damages the lid wiper epi­thelium (as shown by the higher Korb3 scores), com­promises the mucin layer and causes direct epithelial erosion. This results in more severe ocular surface dam­age (higher SICCA OSS).“Paradoxically, the obstruction might cause tear retention in the conjunctival sac, main­taining a more stable liquid tear layer and explaining the better NIBUT,” the authors explained in their paper. “Thus, the eye may be bathed in its own inflammatory tears, which, while relatively more stable than those in lower LDO, remain damaging to the ocular surface.”In contrast, lower LDO may cause severe dysfunction of the neuroinflammatory feedback loop governed by the innervated cavernous body of the lacrimal sac. “This disruption could lead to aberrant tear production signals, resulting in aqueous tear deficiency or poor response to ocular surface stress, manifesting as profound tear film instability (shorter NIBUT, higher NIBUT1 proportion),” the authors wrote. “While the inflammatory backlog might be less concen­trated on the ocular surface than in upper LDO—result­ing in less severe staining (lower SICCA OSS)—the core function of tear film stability is severely compromised.”Considering these results, the authors suggested that providers should be phenotype-specific when managing patients. “Surgical treatment for upper LDO requires caution, as it may alleviate obstruction but disrupt compensatory tear retention,” they concluded. “For lower LDO with epiphora and severe tear film instability, prompt surgery is recommended to restore drainage and potentially reca­librate tear secretion feedback.”Click here for the journal source. Zhang X-L, Chen J-Y Li M-R, et al. Differences in ocular surface parameters in patients with lacrimal duct obstruction at varying sites. BMC Ophthalmology. December 2, 2025. [Epub ahead of print.] This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.