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The Light Switch and the Dimmer: Qualitative Observations to Improve Diagnostic Lacrimal Irrigation
Irene Bermudez-Castellanos1, Raman Malhotra1
1Corneo-Plastic Unit, Queen Victoria Hospital NHS Foundation Trust, East Grinstead, UK.
Purpose:
To emphasise the importance of "soft" observations during lacrimal irrigation in diagnosing lacrimal outflow dysfunction and reporting outcomes of soft factors post-DCR.
Methods:
A retrospective study of patients with ≤ 20% of regurgitation on lacrimal irrigation who underwent DCR surgery. A comparative analysis of percentage reflux of saline (RFX), initial mucus in reflux (IMR), patient-reported transit time of saline (PR-TTS), and resistance encountered (RES) during LS was performed. Validated TEARS score was used. Subjective success was defined as ≥ 2-point improvement in T subscale of TEARS score. Objective success, as a decrease in RFX, RES, PR-TTS and absence of IMR, post-operatively.
Results:
From a total of 253 patients who underwent DCR surgery, 8 patients met the inclusion criteria. All patients were T4 (wiping >10× daily) indoors and outdoors. TEARS score improved after surgery with a mean reduction of T = 2.62, E = 1.63 and A = 1.35 (p < .05) with no significant change in R scores (p = .10). A mean reduction in RFX of 11.75 ± 6.74% and a median improvement of 1 point in PR-TTS and 2 point in RES was observed (p < .05). No significant changes of these parameters occurred in the contralateral side during this period. Subjective and objective success of DCR was 75% and 100%, respectively.
Conclusions:
This study is the first to attempt to combine qualitative "soft" observations during lacrimal irrigation such as IMR, RES and PR-TTS for identifying nasolacrimal outflow dysfunction and reporting outcomes using these parameters of DCR in patients with epiphora and ≤ 20% of fluid regurgitation. These parameters were greater in the more symptomatic side and successfully improved after DCR, making them a valuable tool to reach a provisional diagnosis.
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