Sinonasal effects of external dacryocystorhinostomy.

OBJECTIVE: External dacryocystorhinostomy is thought to cause mucociliary dysfunction by damaging the mucosa, in turn affecting ciliary activity and mucus quality. This study investigated the effect of external dacryocystorhinostomy on sinonasal function. METHODS: Patients scheduled for unilateral external dacryocystorhinostomy who underwent endoscopic nasal examination and paranasal sinus computed tomography were included in this study. A saccharine test was performed on the planned surgical side and the mucociliary clearance time was determined. The sinonasal quality of life was measured in all patients, pre-operatively and at six months post-operatively, using the Sino-Nasal Outcome Test-22. The Lund-Kennedy endoscopic score was also determined in all patients, both pre- and post-operatively. RESULTS: The study comprised 28 patients (22 females and 6 males). A statistically significant difference was found between the pre- and post-operative saccharine test results (p = 0.006), but not between the pre- and post-operative Sino-Nasal Outcome Test-22 scores (p > 0.05). CONCLUSION: This study is one of only a few to investigate the effect of external dacryocystorhinostomy on sinonasal function. The results showed that external dacryocystorhinostomy impairs mucociliary clearance. The surgical procedure is well tolerated and does not significantly change nasal symptom scores.

Transconjunctival versus Transcutaneous Injection of Botulinum Toxin into the Lacrimal Gland to Reduce Lacrimal Production: A Randomized Controlled Trial.

The purpose of this study was to determine and compare the effects between injecting botulinum toxin A (BTX-A) transconjunctivally into the palpebral lobe and transcutaneously into the orbital lobe of the lacrimal gland in patients with epiphora due to lacrimal outflow obstruction. This randomized controlled study included 53 eyes of 31 patients with unilateral or bilateral epiphora. Patients were randomly allocated to receive an injection of BTX-A (3 units) either transconjunctivally (n = 15, 25 eyes) or transcutaneously (n = 16, 28 eyes). For objective assessments, the tear meniscus height and Schirmer's I test with topical anesthesia were measured at baseline and after 2, 6, 12, and 24 weeks of follow-up. Subjective evaluations were performed using the Munk score. After BTX-A injection, patients in both groups experienced significant objective and subjective reductions in tearing at all follow-up times compared to pre-injection (success rate 86.8%), and the effect lasted for a mean duration of 5.63 months. The two delivery routes showed similar clinical effectiveness for a single injected dose of BTX-A. In conclusion, injecting BTX-A via either a transconjunctival or transcutaneous route helps to reduce normal tear production and results in significant improvements in the symptoms in patients with epiphora.

Color Doppler Imaging Features of the Lacrimal Sac in Health and Diseased States.

PURPOSE: The objective of this study is to present Color Doppler imaging (CDI) features of the lacrimal sac in normal and diseased states. METHODS: Prospective study was performed on 20 lacrimal sacs of 20 eyes of 10 patients who underwent Color Doppler imaging at a tertiary care Dacryology service over a period of 6 months. All the patients were subjected to Duplex doppler scanning of the lacrimal sacs. Of the 20 lacrimal drainage systems studied, 8 were normal, 8 had primary acquired nasolacrimal duct obstruction (PANDO) and 4 were that of acute dacryocystitis (AcDac). Patient demographics, clinical presentation, duration of the disease and Color Doppler vascular characteristics like peri-sac vascular flow, peak systolic velocity (PSV), end-diastolic velocity (EDV), resistivity index (RI), arterial spectral waveforms and sac dimensions and wall thickness were analyzed. RESULTS: The vascular flow around the lacrimal sac was increased with higher flow velocities in PANDO as compared to normal and grossly enhanced in AcDac. Flow disturbances were also quite discernible in AcDac. The mean PSV and EDV were 9 & 3.87 cm/sec, 13.07 & 4.63 cm/sec and 18 & 8.5 cm/sec in normal, PANDO and AcDac, respectively. The mean vascular resistivity index increased in patients with PANDO (0.67) and decreased in AcDac (0.53) as compared to the normal (0.57). The arterial spectral waveforms in PANDO and AcDac showed low pulsatility, but the systolic peaks were sharper with more continuous forward flow through diastole in AcDac. This reflects vascular dilatation and reduced resistance to flow in AcDac. CONCLUSION: Characteristic Color Doppler flow parameters can be demonstrated in patients with PANDO and acute dacryocystitis. Color Doppler techniques have the potential to enhance the understanding of lacrimal drainage pathophysiology.

Deterioration of contrast sensitivity in eyes with epiphora due to lacrimal passage obstruction.

PURPOSE: Epiphora causes deterioration in contrast sensitivity in some eye diseases. This study was conducted to investigate contrast sensitivity in eyes with epiphora caused by lacrimal passage obstruction. METHODS: This single-center, prospective case series enrolled 57 patients with unilateral lacrimal passage obstruction. The best-corrected visual acuity (BCVA), contrast sensitivity function, and lower tear meniscus of the affected and contralateral unaffected eyes were compared. The area under the log contrast sensitivity function (AULCSF) was calculated. RESULTS: The BCVA did not significantly differ between the affected and contralateral eyes, while the AULCSF was significantly lower in the affected eyes than that in the contralateral eyes (median 1.35, interquartile range 1.22-1.44 vs. median 1.36, interquartile range 1.28-1.46, P = 0.032). Lower tear meniscus parameters were significantly higher in the affected eyes than those in the contralateral eyes (P < 0.005). CONCLUSIONS: The contrast sensitivity function is significantly diminished in eyes with epiphora caused by lacrimal passage obstruction.

Lacrimal drainage function after cheese wiring of lacrimal passage intubation.

PURPOSE: To investigate how cheese wiring affects lacrimal drainage function by quantitative assessment of tear function and punctal dimensions. METHODS: Patients who underwent lacrimal passage intubation between January 2017 and September 2018 were enrolled prospectively. Among these patients, those with postoperative cheese wiring who received lacrimal passage intubation in one eye met the criteria for further investigation. The subjective symptoms of epiphora, dimensions of puncta, lower tear meniscus, and tear clearance were assessed postoperatively in both the involved eye and untreated contralateral eye. Punctum dimensions were analysed using the digital slit-lamp image. Tear meniscus and tear clearance were assessed by anterior segment optical coherence tomography. RESULTS: Postoperative cheese wiring was observed in 68 of 314 eyes. Among these cases, 36 patients (age 70.5 ± 11.7 years) had cheese wiring only in one eye: with the involvement of both puncta in 15 patients (group A) and only the lower punctum in 21 patients (group B). There was no patient with the involvement of only the upper punctum. While tear function of the involved eyes in group B did not differ from that of the untreated eye, it was significantly decreased in group A compared with that in untreated control eyes (p < 0.05). The tear clearance rate correlated significantly with the upper punctum dimensions (p < 0.05), but not with the lower punctum. CONCLUSION: Analysis of cheese wiring after lacrimal passage intubation with tear function demonstrated that the integrity of the puncta and the canaliculus is important for lacrimal drainage.

Rebamipide promotes lacrimal duct epithelial cell survival via protecting barrier function.

Nasolacrimal duct obstruction (NLDO) is thought to be due to inflammation and fibrosis of lacrimal duct epithelial cells (LDECs). Here we investigated the effect of rebamipide, a drug that is used for the protection of the mucosa and the treatment of gastritis and gastroduodenal ulcers, on LDECs, both in vitro and in vivo. In this study, LDECs were cultured from rabbit lacrimal duct tissues, and the barrier function of LEDCs was examined in vitro via transepithelial electrical resistance (TER) measurement, with or without interleukin (IL)-6 and/or rebamipide. For the in vivo examination, benzalkonium chloride (BAC) was injected into the rabbit lacrimal ducts, followed by the application of rebamipide or a placebo vehicle alone. The results of the in vitro examination revealed a significant decrease in TER in the group treated with IL-6 alone compared with the placebo-vehicle group (p < 0.05) and the group treated with IL-6 and rebamipide (p < 0.01). The results of the in vivo examination revealed that the infiltration of neutrophils under the basement membrane and the disruption of tight junction proteins with BAC injection and rebamipide attenuates the disturbance of tissue construction. These results suggest that rebamipide protects LDECs via an anti-inflammatory effect and preserves the barrier function of those cells.

Human Lacrimal Drainage System Reconstruction, Recanalization, and Regeneration.

Purpose: This review examines the broad contexts of the reconstructive and recanalization strategies of the human lacrimal drainage system.Materials and methods: A PubMed search was performed using individually and combination of the terms "lacrimal," "reconstruction", "recanalization," "canaliculus," "canalicular," "stenosis," "obstruction," "block," "drainage," "disorder," "disease," "nasolacrimal duct (NLD)," "endoscopy," "dacryoendoscopy," "trauma," "laceration," "stents," "repair," "tubes," "tear," "eyelid," "Sisler," "trephine," and "trephination". Selections from these lists were the basis of examination of reconstruction and recanalization strategies of multiple lacrimal disorders and their outcomes.Results: The major focus areas of this review are obstructions of the canaliculi and the NLD, traumatic involvement of the lacrimal drainage and their reconstruction strategies, and dacryoendoscopy-guided recanalization of the NLDs. The review found evidence for lack of uniformity in accurately defining the concepts of lacrimal drainage stenosis, partial or complete obstructions. Canalicular obstructions are difficult to manage and outcomes depend on the location of the obstruction. High success rates were reported in cases of canalicular lacerations managed by repair and silicone intubation. Controversies exists in the recanalization strategies involving the NLD. In the absence of any current regenerative strategies, NLD recanalization appears to be promising, but skepticism is well justified until its long-term effects are well known.Conclusions: Reconstructive strategies in canalicular trauma are highly successful. Recanalization strategies for the lacrimal drainage system are promising and there is a need to explore stem cells and regenerative modalities to take the lacrimal drainage science a step forward.

Outcomes of primary powered endoscopic dacryocystorhinostomy in syndromic congenital nasolacrimal duct obstruction.

Purpose: To evaluate the outcomes of powered endoscopic dacryocystorhinostomy (DCR) in syndromic individuals with congenital nasolacrimal duct obstruction (CNLDO).Methods: A retrospective multicenter case series of patients who required a primary powered endoscopic DCR for refractory CNLDO associated with syndromes or congenital craniofacial abnormalities was performed. A minimum follow-up of more than 6 months was considered for final analysis. Main outcome measures were anatomical and functional success at the last follow up.Results: Twenty primary powered endoscopic DCR's were performed in 12 patients (7 males, 5 females) with syndromic anomalies. The mean age at the time of surgery was 7.6 years (range: 2-22 years). The associated systemic anomalies were Down syndrome (42%, 5/12), ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome (17%, 2/12), gross craniofacial dysgenesis (25%, 3/12) Tessier cleft type 3 (8%, 1/12) and velocardiacfacial syndrome (8%, 1/12). Proximal system agenesis of the upper or lower canaliculus was present in 42% of patients (5 patients, 9 eyes). Adjunctive treatment in the form of Mitomycin C and/or intubation was performed in 55% (11/20) eyes. At a mean postoperative follow-up of 20 months, successful outcomes were noted in 95% of the eyes (19/20). The one eye with an anatomical failure was secondary to a complete cicatricial closure of the ostium and was successfully treated subsequently with a revision endoscopic DCR.Conclusion: Primary powered endoscopic DCR has good outcomes in patients with a CNLDO associated with craniofacial syndromes.

Dacryocystorhinostomy: Evolution of endoscopic techniques after 498 cases.

INTRODUCTION: Endoscopic dacryocystorhinostomy is a well-known surgical practice used to treat nasolacrimal duct obstruction and widely considered as a valid alternative to external approaches. PURPOSE: We present a retrospective case series of 498 endoscopic dacryocystorhinostomies on 401 patients, from July 2004 to May 2018, at the Department of Otolaryngology, San Raffaele Hospital, Milan, Italy. METHODS: Of the 498 procedures, 426 were unilateral and 72 were bilateral dacryocystorhinostomy. All patients underwent routine preoperative workup including fluorescein test (Jones test 1-2), probing and irrigation of the lacrimal way, nasal endoscopy, and maxilla-facial computed tomography scan. Surgical technique was based on nasal endoscopic dacryocystorhinostomy followed by positioning of a Catalano's silicone stent, which was left in place for about 3 months. Anatomical success was defined as a patent ostium on irrigation, whereas functional success was defined as free lacrimal flow on functional test and resolution of epiphora. RESULTS: Anatomic success was achieved in 91.54% cases in primary dacryocystorhinostomy and in 89.36% after revision, whereas functional success was obtained in 90.4% in primary and 85.1% in secondary dacryocystorhinostomies. After a second revision of endoscopic dacryocystorhinostomy, anatomical success was achieved in 90.1% and functional success in 88.7% of procedures. CONCLUSION: Our results confirm that endoscopic dacryocystorhinostomy can be considered as a valid surgical approach to primary nasolacrimal duct obstruction and revision cases. The key aspects in achieving functional and anatomical results are meticulous surgical procedure and precise follow-up.

Patency of the lacrimal drainage system in patients with a peripunctal tumour.

Purpose: To examine the patency or secondary obstruction of the lacrimal drainage system in patients with a peripunctal tumour.Methods: This retrospective, observational, and comparative study included 10 patients with a peripunctal tumour. Lacrimal probing and syringing in all patients and dacryoendoscopic examinations in 5 patients were performed to check for patency of the lacrimal drainage system. Tear meniscus height (TMH) was measured bilaterally in the upper and lower eyelids using anterior segment optical coherence tomography and compared in relation to the affected side using one-way ANOVA.Results: All patients did not complain of epiphora. Probing gave a hard stop and irrigation fluid passed into the nose. A patent punctum/canaliculus was also confirmed by dacryoendoscopy in all of the 5 patients. TMH was not significantly different among the sides (P = .900).Conclusions: This study shows patency of the lacrimal drainage system in patients with a peripunctal tumour and no significant difference in TMH among the sides, resulting in absence of epiphora in all patients.

Congenital nasolacrimal duct obstruction continues trend for spontaneous resolution beyond first year of life.

PURPOSE: To investigate spontaneous resolution of congenital nasolacrimal duct obstruction (CNLDO) beyond 12 months of age in Japanese infants. METHODS: Retrospective, observational case series. We retrospectively reviewed the clinical records of patients diagnosed with CNLDO beyond 12 months of age at Kyoto Prefectural University Hospital, Kyoto, Japan. This study involved 155 cases of CNLDO in 133 Japanese infants diagnosed with CNLDO. All patients chose intervention with either dacryoendoscopic guided probing and stenting or conservative management. The proportion and age of patients who had spontaneous CLNDO resolution were analysed. RESULTS: The patients were divided into two groups: (1) 62 patients with 70 obstructed nasolacrimal ducts (45%) in whom spontaneous resolution occurred and (2) 71 patients with 85 obstructed nasolacrimal ducts (55%) who underwent dacryoendoscopic guided probing and stenting. The mean age of spontaneous resolution was 17.8±5.3 months (range: 12.0-35.4 months). Dacryoendoscopic guided probing and stenting were successful in 83/85 (97.6%) of cases. CONCLUSIONS: Spontaneous resolution of CNLDO can occur in 45% of infants over the age of 12 months. Dacryoendoscopic guided stenting also has high success rates in this patient group, and both treatment options can be proposed to caregivers.

Surgical outcomes of endoscopic dacryocystorhinostomy: analysis of age effect.

There is limited evidence in literature determining age effect on outcomes of endoscopic dacryocystorhinostomy (EDCR) in adult patients with primary acquired nasolacrimal duct obstruction (NLDO). We aimed to analyze the outcomes of EDCR according to age in primary acquired NLDO. A retrospective study was performed on consecutive adult patients and patients were divided into two age groups; group 1 (aged to 61 years) and group 2 (aged 62 to 89 years) based on the average value. The minimum required follow-up period was 6 months. A total of 441 EDCRs performed in 342 patients were enrolled. The anatomical success rate was not significantly different between the two groups (91.8% and 88.2%, P = 0.209). However, the functional success rate was significantly lower in the group 2 (85.1% and 76.9%; P = 0.036). Functional failure was associated with old age and a history of diabetes mellitus (P = 0.024 and P = 0.008). In subgroup analysis of patients with anatomical success but functionally failed EDCR, group 2 had significantly more comorbid conditions such as eyelid laxity (P = 0.026). In conclusion, the comorbid conditions which increase with age may affect functional outcome, especially eyelid laxity, careful preoperative examination of the eyelid and conjunctiva should be emphasized to lacrimal surgeons before performing EDCR.

Amblyopia risk factors in congenital nasolacrimal duct obstruction: A longitudinal case-control study.

PURPOSE: To investigate longitudinal changes in risk factors for amblyopia in children treated with congenital nasolacrimal duct obstruction (CNLDO). METHODS: Retrospective observational case control study. A total of 446 children under 4 years of age who underwent probing and/or intubation for CNLDO between January 2004 and January 2018, and 446 age-matched controls were included. Cycloplegic refraction and ocular alignment were investigated at the time of treatment and after at least one year of symptom improvement. Children were classified as having amblyopia risk factors on the basis of the American Association for Pediatric Ophthalmology and Strabismus guideline in 2013. MAIN OUTCOME MEASURES: The prevalence of amblyogenic refractive errors, and determinants associated with the presence of amblyogenic refractive errors in CNLDO patients. RESULTS: The prevalence of amblyogenic refractive errors in CNLDO patients (5.4%) was similar to that of the control group (6.5%) (P = 0.571). After one year of symptom improvement in CNLDO patients, the prevalence of amblyogenic refractive errors was 4.7%. There was no difference in the prevalence of amblyogenic refractive errors between unilateral and bilateral CNLDO patients. Multivariate analysis revealed that manifest strabismus was the only risk factor related with the presence of amblyogenic refractive errors (odds ratio = 6.383, confidence interval = 1.205-33.826, P = 0.029). CONCLUSIONS: This study found no evidence to suggest that the prevalence of amblyopia risk factors is higher in CNLDO patients compared with normal controls. Manifest strabismus was the only determinant associated with the presence of amblyogenic refractive errors.

Etiopathogenesis of Primary Acquired Nasolacrimal Duct Obstruction: What We Know and What We Need to Know.

PURPOSE: To provide a systematic review of the literature on the etiopathogenesis of primary acquired nasolacrimal duct obstruction (PANDO). METHODS: The authors performed a PubMed search of all articles published in English with specific reference to etiopathogenesis of PANDO or associations of PANDO. Data captured include demographics, study techniques, hypothesis, presumed or confirmed interpretations with regards to pathogenesis, mechanisms, or pathways. Specific emphasis was laid on addressing the lacunae and potential directions for future research. RESULTS: Numerous factors are believed to contribute to the etiopathogenesis of PANDO. The basic pathogenesis involves inflammation, vascular congestion, mucosal edema, fibrosis, obstruction, and stasis. Bony nasolacrimal duct diameter does not appear to play a significant role. There is no convincing data to substantiate nose as the site of disease origin and nasal factors appear to be comorbidities. Hormonal mechanisms are more evidence-based but can only partly explain the pathogenesis. Vascular theories are based on the behavior of perilacrimal cavernous bodies, their autonomic control, and additional structural changes in the helical patterns of connective tissue fiber arrangements. Repeated vascular malfunction leading to structural epithelial and subepithelial changes currently appears to be the most evidence-based and accepted theory. Tear proteomics holds a promise in decoding the etiopathogenesis of PANDO, at least in part. CONCLUSIONS: The etiopathogenesis of PANDO appears to be multifactorial. Hormonal microenvironments, vascular factors, and tear proteomics are promising candidates for further work. There is a need for focused work by Clinician-Scientists and the answers can have far reaching clinical implications.

Surfactant proteins: Role in lacrimal drainage disorders.

Surfactants are complex mixtures of phospholipids and proteins produced by type II alveolar cells of the lungs and play a crucial role in pulmonary physiology. Six types of surfactant proteins (SP) are known; SP-A, SP-B, SP-C, SP-D, SP-G and SP-H. The major role of SP is in reducing surface tension and various immunological functions. SP-A, SP-B, SP-C and SP-D have been demonstrated in the tear film and the epithelium of the lacrimal sac (LS) and nasolacrimal ducts (NLD). All surfactant proteins except SP-G were also isolated from the canalicular tissues. The authors hypothesize that surfactant proteins play a significant role in the pathogenesis of lacrimal drainage disorders; functional nasolacrimal duct obstruction (FNLDO) and infective dacryocystitis.

Outcomes in pediatric powered endoscopic dacryocystorhinostomy: a single-center experience.

PURPOSE: The purpose of the article is to report the outcomes of powered endoscopic dacryocystorhinostomy (PEnDCR) in pediatric patients. METHODS: A single-center, single surgeon, retrospective, interventional, non-comparative case series was performed on all pediatric patients who underwent PEnDCR between July 2014 and July 2017. Patients with associated congenital anomalies like single punctum agenesis or lacrimal fistula were excluded. Surgery was performed as per standard protocols published earlier. Data collected include demographics, clinical presentations, past interventions, indications for the surgery, intraoperative and postoperative complications, postoperative ostium characteristics, and anatomical and functional success. RESULTS: Ninety-one eyes of 83 children underwent PEnDCR during the study period. Mean age was 8.32 years and epiphora was the most common presentation (81%, 74/91). The most common indication for PEnDCR was persistent congenital nasolacrimal duct obstruction refractory to earlier interventions of probing or intubation. Postoperative ostium assessment at 4 weeks showed a well-healed ostium with a dynamic internal common opening in 86.8% of the eyes. Edge granulomas of the ostium were the most common abnormal finding in the postoperative period (9.8%, 9/91) and all except one could be managed conservatively. At 6 months follow-up, five eyes showed anatomical failure and additional two eyes showeXd functional failure. Two of anatomical failure group and one of functional failure underwent a second intervention. The final anatomical and functional success were noted in 96.7% (88/91) and 95.6% (87/91), respectively. CONCLUSIONS: This study shows that PEnDCR is a safe surgery for pediatric populations with a high success rate of beyond 95%.

Comparing Outcomes of the Standard Technique of Endoscopic DCR with Its Modifications: A Retrospective Analysis.

OBJECTIVE: To compare the outcomes of various techniques of endoscopic dacryocystorhinostomy (DCR). STUDY DESIGN: Retrospective case record analysis. SETTINGS: Tertiary care referral center. SUBJECT AND METHODS: Retrospective analysis of case records was carried out pertaining to the period from January 1996 to September 2017 with respect to patients who had undergone endoscopic DCR with either the standard technique or one of its modifications. Case notes showing well-documented preoperative evaluation, operative details, postoperative assessment, and minimum 6-month follow-up were considered. The outcomes were measured on the basis of patients' postoperative symptoms, clinical examination, and sac-syringing results. RESULTS: A total of 423 patients were included in the study. Of these, 169 underwent standard endoscopic DCR; 87, endoscopic DCR with stent; 19, endoscopic DCR with mitomycin C; 62, powered DCR; 29, laser-assisted DCR; and 57, balloon DCR. There was no statistically significant difference in success rates, recurrences, or complications of various techniques at 3 or 6 months. Mean operating time was lowest for balloon DCR (mean ± SD, 27.1 ± 3.1 minutes), followed by standard endoscopic DCR (38.2 ± 3.6 minutes; P = .001). CONCLUSION: Standard endoscopic DCR and its more sophisticated modifications were equally effective and safe in managing distal nasolacrimal drainage obstruction. Balloon DCR, followed by standard endoscopic DCR, was significantly faster than other techniques.

Combination Surgery of Silicone Tube Intubation and Conjunctival Resection in Patients with Epiphora.

PURPOSE: To compare the success rates of performing only silicone tube intubation versus carrying out both conjunctival resection and silicone tube intubation. METHODS: The subjects of this study involved 62 patients (96 eyes) between October 2015 and May 2017 who were diagnosed as having punctal stricture or nasolacrimal duct stenosis. Out of 96 eyes, 47 underwent only silicone tube intubation, and 49 underwent both silicone tube intubation and conjunctival resection. Three parameters were measured at 1, 3, and 6 months after the surgery: the area of the tear meniscus using RTVue-100 anterior segment optical coherence tomography, the height of the tear meniscus using a slit lamp microscope, and the subjective satisfaction of patients as a result of improved sympotms like epiphora. The surgery was considered successful when the patients' experienced the resolution of symptoms and reduction of the area and height of the tear meniscus. RESULTS: The area of the tear meniscus, height of the tear meniscus, and subjective satisfaction of patients was superior in the group that underwent both silicone tube intubation and conjunctival resection compared silicone tube intubation only. Based on these results, the success rate of the surgery was 68.9% in the group that underwent only silicone tube intubation and 78.7% in the group that underwent both silicone tube intubation and conjunctival resection. CONCLUSIONS: The resection of relaxed plica semilunares seems to increase the success rate of silicone tube intubation through the reduction of the area and height of the tear meniscus. Therefore, after determining the degree of conjunctivochalasis, if it was found to be severe, a combination with conjunctival resection was expected to increase the success rate of the surgery.

Novel taste test for nasolacrimal duct obstruction using denatonium benzoate: a randomized controlled pilot study.

OBJECTIVE: To evaluate a novel, simple, noninvasive method (known as the "bitter taste test") of establishing nasolacrimal duct patency in healthy asymptomatic eyes. DESIGN: Double-blind, randomized controlled pilot study. PARTICIPANTS: Healthy asymptomatic medical students, residents, and allied health staff at our institution. METHODS: Participants, aged 18-35 years (n = 28) with assumed normal lacrimal function, were randomized to the interventional group (100 parts per million denatonium benzoate in sterile water, n = 14) or to the control group (sterile water only, n = 14). All participants were pretreated with topical tetracaine in their right conjunctival cul-de sac, followed by 3 drops of the experimental solution spaced 1 minute apart. The primary outcome was whether participants reported a strong, persistent bitter taste. The secondary outcome was the time-to-taste. All participants received lacrimal irrigation. The Fisher's exact test was done using GraphPad online software. RESULTS: All participants in the interventional group reported the presence of the bitter solution. None of the participants in the control group reported bitterness (p < 0.001, Fisher's exact test). Time-to-taste was within 15 minutes for 71% of the intervention group (n = 10); within 30 minutes for 79% (n = 11); and within 2 hours for 100% (n = 14). The bitterness typically persisted for 1-2 hours. All participants had normal lacrimal systems to irrigation. No adverse events were reported. CONCLUSIONS: The bitter taste test demonstrates a promising ability to assess nasolacrimal duct patency under physiologic conditions in healthy participants. Further research is needed to validate this method in a clinical sample of patients with nasolacrimal duct obstruction.