Lacrimal irrigation before intraocular surgery: Where are we today?

Preoperative screening for nasolacrimal duct obstruction (NLDO) is an essential yet often overlooked aspect of surgical planning in ophthalmology. NLDO can significantly impact the ocular environment, particularly affecting the conjunctival cul-de-sac and the microbial flora. The lacrimal drainage system plays a critical role in maintaining ocular surface health by facilitating tear drainage and reducing the bacterial load through constant tear flow. When the duct is obstructed, tear stasis occurs, creating an environment conducive to bacterial proliferation, altering the natural ocular microbiome. Hayashi et al. reported that of 125 precataract surgery patients who were diagnosed with NLDO, 44.8% of patients showed significant microbial growth which included Methicillin-resistant Staphylococcus aureus in some cases.[1] The data are clear: the higher rates of nasolacrimal duct (NLD) obstruction among patients who developed endophthalmitis indicate that NLDO is a significant risk factor for postoperative endophthalmitis.[2]

We, ophthalmologists, are of course acutely aware of this – one study showed that 92% of the surveyed ophthalmologists agreed that NLD patency should be checked before performing cataract surgery.[3] The dichotomy in practice, however, is about the technique used to assess the NLD patency - 59.6% felt that checking for regurgitation by applying pressure over the lacrimal sac area also known as ROPLAS was sufficient, but 32.6% preferred to perform lacrimal irrigation to assess NLD patency. Many authors have recommended different techniques in screening for NLDO/primary acquired NLDO such as ROPLAS, micro-reflux test, and the gold standard – lacrimal irrigation.[4,5]

ROPLAS is a method of assessing the NLD status that Thomas et al. described in detail. They reported that sensitivity and specificity of ROPLAS were 93.2% and 99.3%, respectively, and suggested that irrigation need not be a part of routine precataract workup in all patients.[5] In contrast, Kim et al. studied a group of 8369 patients in whom ROPLAS and lacrimal irrigation - both were performed, and they found that ROPLAS when used alone had very low sensitivity and low positive predictive value in detecting NLDO as compared to lacrimal irrigation.[6] In contrast to Thomas et al., they recommended performing ROPLAS and lacrimal irrigation in every patient as part of the routine preoperative workup before cataract surgery. Shenoy et al. reported their findings of a large (87,144 eyes) cohort of patients who underwent cataract surgery. In their study, 48,071 eyes underwent lacrimal irrigation preoperatively, and ROPLAS was performed in 39,073 eyes. Eventually, the rates of postoperative endophthalmitis were comparable among the eyes undergoing either syringing test or ROPLAS before cataract surgery.[7]

So, what does one do in the face of such confusing data? The drawback about the findings of Thomas et al. remains their small sample size, and in the paper by Kim et al., lacrimal sac irrigation was performed by optometrists and not be ophthalmologists - which may not be possible everywhere. In addition, lacrimal irrigation requires training in performing it and interpreting its results accurately.[5,6] In the paper by Shenoy et al., their reported rates of postoperative endophthalmitis in both groups were identical, but the number of cases of NLDO among the patients in each of those two groups was not reported, and NLD status in the endophthalmitis patients was not confirmed. The paper neither addresses the question of ROPLAS being superior to lacrimal sac irrigation in diagnosing NLD obstruction nor does it confirm the previously reported findings that NLDO increases the chances of developing postoperative endophthalmitis, limiting the utility of this paper’s findings.[7]

At the end of the day, we must resist the temptation to allow a single dictum to dictate our practice. We as clinicians have a mandate to examine every patient thoroughly and to treat the patient in the best way to address their symptoms. And preoperative NLD assessment too requires a balanced approach.[8] Preoperatively, a history of epiphora must be actively elicited in all patients. All symptomatic patients and those with any clinical red flags such as an increased tear meniscus height, matted eyelashes, or visible discharge must undergo lacrimal irrigation by a trained professional. Assessment of NLD status by checking for ROPLAS in an asymptomatic patient without obvious signs of epiphora may be considered acceptable.

The point of this editorial is to reinforce the need to assess and document NLD patency preoperatively before any intraocular surgery. However, clinical practice cannot be dictated by a single study or a universal rule. Each patient deserves individualized care, guided by our clinical judgment, as we are ultimately accountable to them – not to generalized principles or blanket guidelines.