J Korean Ophthalmol Soc.  2020 Apr;61(4):325-333. 10.3341/jkos.2020.61.4.325.

Associations between the Munk Score and Tear Film Scan Revealed byCorneal Topography after Dacryocystorhinostomy

• Kim SY
• Kim NR
• Jung JW
• Kang SM

• KMID: 2500096
• DOI: http://doi.org/10.3341/jkos.2020.61.4.325

Abstract

Purpose
We evaluated changes in the tear film parameters of the corneal surface, and their correlations with Munk scores, based on corneal topographic scans of patients with nasolacrimal duct obstructions who underwent dacryocystorhinostomy (DCR). We explored whether tear parameters can serve as useful indicators of functional surgical success.
Methods
We assessed 72 eyes of 45 patients diagnosed with nasolacrimal duct obstruction who underwent DCR. Tear film parameters were measured via corneal topography (Keratograph® 5M) once before, and three times after surgery, and included tear meniscus height (TMH), and the initial and average keratographic tear break-up time (NIKBUT-first and NIKBUT-average, respectively; measured noninvasively).
Results
The three postoperative TMH values were 0.31 ± 0.20, 0.30 ± 0.22, and 0.29 ± 0.15 mm, all of which were significantly lower than the preoperative value of 0.48 ± 0.29 mm (all, p < 0.001). Three months after surgery, the NIKBUT-first (6.90 ± 3.39 seconds) was significantly shorter than the preoperative value (8.39 ± 5.34 seconds; p = 0.030). The preoperative NIKBUT-average did not differ significantly from the values at the three postoperative timepoints (p = 0.756, p = 0.753, and p > 0.999). Changes in the Munk score after surgery correlated significantly with changes in the TMH (r = 0.46, p < 0.001). When functional success was defined as a Munk score ≤ 1, the area under the curve (AUC) value corresponding to the ability of TMH to define functional success of 0.995, was statistically significant (cut-off of 0.31 mm; p < 0.001).
Conclusions
The TMH DCR correlated significantly with the Munk score, which is a quantitative measure of clinical symptom severity. The ability of TMH to define functional surgical success was excellent.

Keyword

Endonasal dacryocystorhinostomy; Non-invasive keratograph break-up time; Keratograph 5M; Tear meniscus height