Evaluation of the Canalicular Entrance Into the Lacrimal Sac: An Anatomical Study

Morphometric and morphological evaluation of the nasolacrimal groove in 150 dry bones in the Anatolian population

PUPOSE

In this study, we aimed to evaluate the anatomical features of the nasolacrimal groove in detail by providing a morphological classification based on morphometric evaluations of the nasolacrimal groove.

METHODS

A total of 150 sagittal dry bones in the Department of Anatomy, Faculty of Medicine, Istanbul University were evaluated. The length and the width at different points of the nasolacrimal canal were calculated. According to the widths of the nasolacrimal canal ten different morphological types were revealed.

RESULTS

The length of the canal was found as mean 13.62 ± 2.42 mm on the right and 12.44 ± 2.68 mm on the left side. The entrance, the base, the upper and the lower thirds of nasolacrimal canal were 6.22 ± 1.19 mm, 7.95 ± 1.85 mm, 5.85 ± 1.06 mm, 6.60 ± 1.54 mm, on the right and 6.08 ± 1.16 mm, 7.24 ± 1.64 mm, 5.45 ± 1.29 mm, 6.23 ± 1.48 mm, on the left side, respectively. The width of the entrance of the nasolacrimal canal was the narrowest width compared to the base, upper and lower thirds in 7/10 types of 71/150 cranial bones.

CONCLUSION

This comprehensive morphological classification of the nasolacrimal groove sheds new light on its complex variations. We support that the finding of this study has the potential to improve the precision of diagnostic assessments and guide specific therapeutic interventions for patients with lacrimal drainage disorders.

[Anatomical structure and morphometric parameters of the distal segment of the lacrimal drainage system]

The article analyzes the literature data concerning the anatomical structure of the tear ducts with a focus on morphometric studies of individual structures. It is noted that, despite the high information content of cadaveric studies, most of the information to date has been obtained with the use of intravital radiation visualization methods. It is shown that the lacrimal drainage system has age, gender, and racial characteristics. Most studies focus on features of the bone nasolacrimal canal, while there is a relative shortage of research devoted to soft-tissue nasolacrimal duct. The analysis showed that most of the studies are devoted to particular morphometric indicators, which makes it difficult to obtain a complete objective picture of the size of the tear duct. Information about its volume can be found only in a couple of studies. The numerical values of the obtained data vary, which can be explained by a different approach to the selection of research subjects, sample sizes, anatomical criteria and the calculation method of morphometric parameters. There are only a few studies on morphometric parameters of the nasolacrimal duct in healthy humans, which is extremely important for determining the pathogenesis of disorders of the patency of the lacrimal drainage system.

Cadaveric Evaluation of the Canalicular-Lacrimal Sac-Mucosal Folds and Clinical Implications

PURPOSE

The purpose is to study the anatomical variations of the characteristic mucosal folds at the canalicular-lacrimal sac junction and their potential clinical implications.

METHODS

Twelve lacrimal drainage systems of six fresh frozen Caucasian cadavers were studied to assess the openings of the common canaliculus into the lacrimal sac. A standard endoscopic dacryocystorhinostomy was performed until complete lacrimal sac marsupialization and reflection of the flaps. All specimens were subjected to clinical assessment of lacrimal patency via irrigation. A high-definition nasal endoscopy assessed the internal common opening and the mucosal folds in its close vicinity. Probing at the internal common opening was performed to aid in the assessment of the folds. Videography and photo documentation was performed.

RESULTS

All 12 specimens had a single common canalicular opening. Ten of the 12 specimens (83.3%) were noted to have canalicular/lacrimal sac-mucosal folds (CLS-MF). Anatomical variations were noted across these 10 specimens and included inferior 180° (n = 6), anterior 270° (n = 2), posterior 180° (n = 1), and 360° CLS-MF (n = 1). Cases were randomly chosen to demonstrate the clinical implications of misinterpreting them as canalicular obstructions or the potential to cause an inadvertent false passage.

CONCLUSION

The inferior 180° was the most common CLS-MF noted in the cadaveric study. It is helpful for clinicians to recognize the prominent CLS-MF and their clinical implications intraoperatively. Further fundamental work is needed to characterize the anatomy and the possible physiological role of CLS-MFs.

Valvular System of the Lacrimal Drainage Pathway and the Valve of Rosenmüller

The valves of the lacrimal drainage system are an enigma with a rich eponymous history. The unidirectional flow of tears along with the ultrastructural demonstration of distinctive mucosal folds on the luminal surface has rekindled an interest in them. The first in vivo direct demonstration of the valve of Rosenmüller and its functions has laid to rest some of the controversies of its existence and that of the valve of Huschke. The dynamic assessment of the valve of Rosenmüller has shown a well-defined functional role in the facilitation of unidirectional tear flow. The present mini review describes the embryological aspects, brief overview of the eponymous valves, techniques for their identification along with recent structural and functional aspects of the valve of Rosenmüller.

Soft stop on syringing and probing may have a high false-positive rate in diagnosing pre-sac obstruction

Purpose

To determine the diagnostic value of 'soft stops' encountered during lacrimal syringing and probing.

Methods

Single-center retrospective review. Adult patients with epiphora attending a tertiary lacrimal clinic from May 2010 to April 2021 were reviewed. Cases with evidence of soft stop encountered during lacrimal syringing/probing were included, and patients with possible canaliculitis or a history of lacrimal surgery were excluded. Findings of syringing/probing consistent with pre-sac obstruction were correlated with dacryocystography (DCG) and surgical findings.

Results

53 (10.2%) canalicular systems had soft stops on syringing/probing and were included in the analysis. The mean age of the patients was 63.8 ± 15.6 (range 28–87) years, and 27 (65.9%) were females. Intraoperative examination findings were available for 27 of 30 cases that underwent lacrimal surgery and DCG was available for 40 systems. Pre-sac obstruction found on syringing/probing was confirmed in 40% and 37% of cases on DCG and surgery, respectively. The correlation between syringing/probing and DCG was stronger for canalicular than for common canalicular location (p = 0.016). Canalicular stenosis on syringing/probing manifested as pre-sac abnormality on DCG in 5/7 (71.4%) compared to 0/6 common canalicular stenosis cases (p = 0.021). Based on the surgical findings, the false-positive rate of a soft stop on syringing/probing was highest for common canalicular ‘stenosis’ (100%) and lowest for canalicular ‘block’ (45.5%; p = 0.093). Findings of pre-sac obstructions on DCG were confirmed in 85.7% of the cases intraoperatively (p = 0.035 compared to syringing/probing alone).

Conclusions

Soft stops on probing showed poor correlation with DCG and surgical findings, particularly in common canalicular location.

Chronologic Analysis of Tear Dynamics on Blinking Using Quantitative Manometry in Healthy Humans

PURPOSE

To analyze the tear dynamics during blinking by measuring the inner pressure of the upper lacrimal drainage system.

METHODS

This observational study involved 11 healthy bi- or tricenarian volunteers. Direct manometry was performed using a fiber optic pressure sensor inserted into the conjunctival sac, upper/lower canaliculus (5 mm from punctum), and inferior lacrimal sac (15 mm from punctum) during both involuntary and intentional tight blinking. Pressure was measured 200 times/second during 3 separate blinks and then chronologically analyzed.

RESULTS

In all subjects of all locations during both types of blinking, the inner pressures during the stationary eyelid closing/opening were positive/approximately zero, while a positive/negative pressure spike was observed during the eyelid closing/opening movement. The averages of the maximum pressure in the spike during the intentional tight blinking (tPmax: mm Hg) in the conjunctival sac, upper/lower canaliculus, and lacrimal sac were 8.00, 12.39/12.93, and 10.59, respectively, while for the minimum (tPmin: mm Hg), the pressures were -3.18, -3.91/-3.43, and -3.31, respectively. The tPmax and tPmin in the lacrimal duct were positively correlated with that of the conjunctival sac, which suggested synchronism of the drainage system. However, the tPmax in the canaliculus was significantly higher than that of the conjunctival sac, which suggested that tears do not flow from the conjunctival sac into the lacrimal duct during eyelid closure.

CONCLUSIONS

The upper lacrimal drainage system functions as one united lumen in the lacrimal pump. The positive /negative pressure spike is essential for the lacrimal pump to efficiently eject/aspirate the tear from the lacrimal/conjunctival sac.

Implantation of a Coronary Stent Into the Canaliculus of a Human Cadaver: A Pilot Study

PURPOSE

To evaluate the possibility of implanting a drug-eluting coronary stent into the canaliculus of a human cadaver.

METHODS

The punctum and canaliculus of an embalmed human cadaver were identified and dilated using a punctum dilator and Bowman probes. At this stage, the integrity of the lacrimal drainage system was assessed by dacryoendoscopy. A drug-eluting coronary stent, which was collapsed around a balloon at the tip of a catheter, was inserted into the canaliculus. The balloon was inflated to expand and lock the spring-like stent into position. The balloon catheter was then deflated and removed from the canaliculus. Dacryoendoscopy was used once again to assess the position of each stent after implantation.

RESULTS

The four canaliculi of one human cadaver were successfully identified, dilated, and intubated using drug-eluting coronary stents. Dacryoendoscopy confirmed that each stent achieved a satisfactory position within the canaliculi. The seamless integration of the stent with the surrounding tissues resulted in a significant dilation of the canaliculi. The procedure was deemed short and simple, with the time required to implant a stent into the canaliculus and asses its position being less than a minute.

CONCLUSIONS

Canalicular obstructions can often be a source of therapeutic challenges. Our pilot study shows that a drug-eluting coronary stent can be implanted with precision into the canaliculus of a human cadaver. We propose that at least some canalicular obstructions could be treated using a novel rigid mesh tube similar to drug-eluting coronary stents.

Immediate Endoscopic Dacryocystorhinostomy in Patients With New Onset Acute Dacryocystitis

OBJECTIVES

To compare the results of immediate endoscopic dacryocystorhinostomy (En-DCR) and delayed En-DCR in the treatment of new-onset acute dacryocystitis (AD).

STUDY DESIGN

This report describes a prospective randomized controlled interventional case series.

METHODS

Between April 2009 and May 2019, 176 adults presenting at a tertiary eye care center with new-onset AD manifesting within the last 48 hours were randomized into two groups. Altogether, 160 patients (48 male, 112 female) were included in this study, with a median age of 52.8 years (range: 18-82). Patients in group A underwent urgent En-DCR, although those in group B underwent a delayed En-DCR after 2 to 5 days of systematic antibiotic treatment. Variables compared between these two groups included the time for resolution of acute external inflammation, free lacrimal passage reconstruction (LPR) success rates, and complication rates.

RESULTS

Postoperative data were collected from 86 patients in group A and 74 patients in group B. Patients that underwent immediate En-DCR exhibited a quicker resolution of acute inflammation (P < .05). Patients that underwent delayed surgery experienced compilations of acute inflammation, with 10 ultimately developing skin fistulization and 4 exhibiting orbital cellulitis before surgery. The success rate of LPR at 12 months after surgery was higher in group A (81/86 94.2%) relative to group B (62/74 83.8%; P < .05).

CONCLUSIONS

Immediate En-DCR is associated with quicker disease resolution and a higher long-term success rate, although reducing the incidence of complications including skin fistulization and the spread of infection.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021 Laryngoscope, 2021.

In Vivo Morphological Study of Common Canalicular Orifice and Its Impact on Lacrimal Probing

PURPOSE

To study the in vivo morphology of common canalicular/lacrimal sac mucosal folds (CLS-MFs) and their relationship with probing findings.

METHODS

Consecutive cases undergoing endoscopic dacryocystorhinostomy had endoscopic examination of the internal canalicular orifice (ICO). Details of CLS-MFs folds, probing findings, and outcomes of dacryocystorhinostomy were analyzed.

RESULTS

Thirty-six lacrimal systems of 34 patients (mean age, 58 years; 7 males, 27 females) were examined. All 36 lacrimal systems had a single common canalicular orifice entering the lacrimal sac (100%). Overall, 61.1% (22/36) had visible CLS-MFs, out of which only 13.6% (3/22) were overhanging the ICO requiring manipulation of the probe to enter the lacrimal sac. The orientation of folds was superior 180° in 2, posterosuperior in 2, posterior in 6, inferior 180° in 6, and inferior 270° (excluding 10-2'o clock quadrant) in 6 systems. Two cases preoperatively labeled as having common canalicular obstruction, based on lacrimal syringing, had CLS-MFs impacting against the ICO without any anatomical obstruction. One of 5 cases with lacrimal sac mucocele had CLS-MFs located along the posterosuperior edge extending for 270°, which resulted in a soft stop on preoperative lacrimal syringing findings. Only 1 case had a true membrane (2.7%) overlying the ICO, which required excision. No differences in outcomes of dacryocystorhinostomy were observed between cases with CLS-MFs versus without any folds.

CONCLUSION

CLS-MFs display a wide variation in terms of morphological location and extent along the ICO. They might be responsible for the false soft stop observed in some cases on preoperative syringing and do not require excision.

Valve of Rosenmüller: Endoscopic Real-Time Analysis of Two Subtypes and Potential Functional Implications

PURPOSE

The aim of this study was to examine the endoscopic anatomy of the valve of Rosenmüller in real-time and its potential functional implications.

METHODS

High-definition endoscopic documentation of the valve of Rosenmüller (VOR) during 50 powered endoscopic dacryocystorhinostomy over a period of 2 years were reviewed. The presence or absence of the valves were assessed and when present, each of the valves were studied for their anatomical configuration, shape, precise location, and changes with opening and closing of the internal common opening (ICO) and with the presence and absence of the probe.

RESULTS

VOR was noted in 68% of the subjects studied and 2 distinct subtypes were noted with type I being more common. The Type 1 VOR was a stand-alone, freely mobile, elliptical valve arising from the superior or postero-superior portion of the medial edge of the ICO. The Type II VOR was a group of a superior and inferior mucosal fold, arising from the superior and inferior portions of the medial edge of the ICO. When the ICO opens slowly, the valve tends to fall outwards towards the lacrimal sac. When the ICO slowly closes back, the valve moves inward towards the common canaliculus.

CONCLUSIONS

This is the first study to demonstrate the in-vivo presence of VOR. Two different types of VOR were noted with characteristic shapes, locations, and movements of each. Where present, VOR fulfills the criteria of a true valve. The study proposes that the term "valve of Huschke" is a misnomer and when present, is actually part of the overall anatomical and functional unit of VOR.Detailed anatomical features of the valve of Rosenmϋller can help our understanding of the focal anatomy and tear rheology.

Scanning Electron Microscopic Features of the Canalicular Entrance Into the Lacrimal Sac

PURPOSE

The aim of this study was to examine the ultrastructural features of the canalicular entrance into the lacrimal sac.

METHODS

Ten openings of the common canaliculus into the lacrimal sac from 10 lacrimal sacs obtained during a dacryocystectomy were studied. Each of the openings were completely excised with 3-4 mm margins on all sides and transported to the laboratory in 2.5% glutaraldehyde. The analysis was performed using the standard protocols of scanning electron microscopy (SEM). The openings, their edges, canalicular lacrimal sac-mucosal folds, and internal surfaces were studied.

RESULTS

Of the 10 common canalicular openings studied, the upper and lower canaliculi opened into a common canaliculus in all the cases. The terminal portion of the 2 canaliculi had a common wall, which appeared like a septum, just proximal to the beginning of the dilated common canalicular portion. In 60% (6/10) of the cases, a diverticular or a type III sinus of Maier (SOM) was noted. The surface of this diverticulum was smooth and lined by stratified columnar epithelium, reflecting its lacrimal sac origins. Interestingly, the junction of the epithelial change from stratified squamous to columnar could be appreciated clearly in 80% (8/10) of the cases and was mostly located just within from the edge of the internal common opening (ICO). The canalicular lacrimal sac-mucosal folds could be appreciated in 70% (7/10) samples, being very defined and prominent in 30% (3/10).

CONCLUSIONS

The common merged wall of the 2 canaliculus is the most proximal and prominent structure noted on an end-on view of the ICO. Diverticular variant of the sinus of Maier is common. The junction of the epithelial change from stratified squamous to columnar is appreciated just within the edge of the ICO.Detailed anatomical features of the common canalicular opening into the lacrimal sac can help our understanding of the focal anatomy and tear rheology.

Surgical outcomes of external dacryocystorhinostomy and risk factors for functional failure: a 10-year experience

PURPOSE

To analyze the surgical outcomes of external dacryocystorhinostomy (DCR) and the risk factors associated with functional failure.

METHODS

We reviewed the medical records of 769 patients who underwent external DCR for primary lacrimal drainage obstruction between 2005 and 2014. Recorded data included intraoperative anatomical findings, postoperative diagnosis, and surgical outcomes. We performed univariate and multivariate analyses to identify risk factors for functional failure.

RESULTS

Of the 769 cases, primary nasolacrimal duct obstruction (NLDO) was diagnosed in 457 cases; common canalicular obstruction in 228 cases; and canalicular obstruction in 84 cases. Anatomical success was achieved in 98.8% (760/769) and functional success in 81.9% (630/769) of the cases. An analysis of 760 anatomically successful DCRs showed that common canalicular obstruction (OR=1.752, P=0.014) and canalicular obstruction (OR=2.058, P=0.015) were independent risk factors for functional failure. In a subgroup analysis of patients with primary NLDO, patients with a small lacrimal sac had a significantly higher risk of functional failure (OR=2.500, P=0.018).

CONCLUSIONS

The overall surgical outcomes of external DCR were favorable in this case series. Site of obstruction was an important risk factor for functional failure in cases with primary lacrimal drainage obstruction. A small lacrimal sac was also found to be a risk factor for functional failure in cases with primary NLDO.

In Vivo and Cadaver Studies of the Canalicular/Lacrimal Sac Mucosal Folds

Purpose. The study aimed to investigate canalicular/lacrimal sac mucosal folds (CLS-MFs) in vivo and in cadavers in order to explore their functional roles in the lacrimal drainage system. Method. The observations of CLS-MFs in vivo were performed on 16 patients with chronic dacryocystitis after undergoing an endonasal endoscopic dacryocystorhinostomy (EE-DCR). The lacrimal sacs and common canaliculi of 19 adult cadavers were dissected. The opening/closing of an orifice and mucosal fold was recorded. All of the specimens were subjected to a histological examination. Results. The upper and lower lacrimal canaliculi in all of the samples united to form a common canaliculus that opened to the lacrimal sac. CLS-MFs were observed in 10 of the 16 patients (62.5%) and 9 of the 19 cadavers (47.4%). The orifices or mucosal folds could be opened or closed when related muscles contracted or relaxed. Histological sections showed a mucosal fold at one side of an orifice. Conclusion. Common canaliculus is the most common type that the canaliculus opens to lacrimal sac. CLS-MFs exist in a certain ratio that can be opened/closed with the movement of the orifices. They may be involved in the drainage of tears or the pathogenesis of acute dacryocystitis or lacrimal sac mucocele.

A prospective outcome study of membranous and solid distal common canalicular obstructions

PURPOSE

To prospectively evaluate the surgical outcomes of membranous and solid distal common canalicular obstructions (CCOs) following endoscopic dacryocystorhinostomy (EnDCR) and lacrimal intubation combined with either membranotomy or trephination.

METHODS

This was a prospective, non-randomized, consecutive interventional case series. Inclusion criteria included patients undergoing EnDCR with evidence of a membranous block or more solid obstruction of the distal common canaliculus, treated with membranotomy or canalicular trephination. Complete CCO was confirmed pre-operatively using dacryocystography and dacryoscintigraphy. All patients received bicanalicular intubation for 3 months with a minimum follow-up of 12 months. Functional and anatomical success was assessed at 4 weeks, 3 months, and 12 months following surgery. Functional success was defined as subjective improvement of epiphora and anatomical success as the presence of a patent ostium and a positive dye test on nasal endoscopy.

RESULTS

Twenty-nine patients were included in the study with a mean age of 58 years. Twenty-one patients (72%) received a membranotomy and eight (28%) required trephination. At 12 months, the functional and anatomical success rate in the membranotomy group was 90% (19/21) and 100% (21/21), respectively, and in trephination group the functional and anatomical success rate was 63% (5/8). There were no intra-operative or lacrimal stent-related complications.

CONCLUSIONS

Identifying and excising distal CCOs in association with EnDCR and lacrimal intubation is associated with a high degree of functional (83%) and anatomical (90%) success. The success of membranous obstructions appear be superior to outcomes for solid obstructions of the distal common canaliculus that require trephination.

Two Types of the Sinus of Maier: An Anatomic Study

PURPOSE

To show the morphological characteristics of two different types of the sinus of Maier, one with a lacrimal sac diverticulum supplied by separate canalicular openings, and the other with a terminal dilatation of the common lacrimal canaliculus.

METHODS

Twelve coronal specimens (6 right and 6 left) from 6 Japanese cadavers (age range, 70-90 years at death) and 15 axial specimens of 11 Japanese cadavers (8 right, 7 left; age range, 45-89 years at death), fixed in 10% buffered formalin, were used. All specimens were stained with Masson's trichrome.

RESULTS

The sinus of Maier, with a lacrimal sac diverticulum supplied by separate canalicular openings, was shown in one coronally sectioned group, with a diameter of 1.29 mm. The mucosa between both openings (0.282 mm length) comprised stratified squamous epithelia, which was characteristic of the lacrimal canaliculi. The diverticular mucosa was lined by a stratified columnar epithelium, which corresponded to the lacrimal sac. The sinus of Maier, with a terminal dilatation of the common lacrimal canaliculus and with a diameter of 0.51 mm, was demonstrated in one axially sectioned group.

CONCLUSIONS

The morphological characteristics of two types of the sinus of Maier were described in this study. One type was the lacrimal sac diverticulum supplied by separate canalicular openings, and the other was the terminal dilatation of the common lacrimal canaliculus.

Movement of internal canalicular orifice in association with blinking: direct observation after dacryocystorhinostomy

PURPOSE

To examine movement of the internal canalicular orifice with blinking and lacrimal drainage under endonasal endoscopic observation after dacryocystorhinostomy.

DESIGN

Observational anatomic study.

METHODS

Twenty internal canalicular orifices (right 9, left 11) from 15 patients (age range: 44-77 years) who underwent endoscopic endonasal dacryocystorhinostomy were prospectively examined. The patients sat on a chair with the chin projected slightly upward while digital images were taken. After examining the movement of the internal canalicular orifice with blinking, the patient's eye was stained with fluorescein dye, and diffusion from the orifice was examined with blinking.

RESULTS

The internal canalicular orifice closed during eyelid opening, although always incompletely. In eyelid closing, the orifice opened, and was pulled laterally without folds. All 20 internal canalicular orifices formed a diverticulum. Three specimens illustrated the upper and lower canalicular ends emptying into the diverticulum. The closing of these canalicular ends was always incomplete. Movement of the internal canalicular orifice was slight during normal blinking, but forced blinking resulted in more movement. Movement of the lacrimal sac wall was slight. During the first few seconds without blinking, no fluorescein dye flowed from the orifice. After several blinks, fluorescein dye flowed out slowly from the orifice, and increased in volume with more blinking. The fluorescein dye traveled inferiorly by gravity. A forced blinking was related to more dye inflow.

CONCLUSIONS

The internal canalicular orifice incompletely closed during eyelid opening, but this orifice largely opened during eyelid closing, with a slow gravitational inflow of lacrimal fluid.

Treatment of punctal occlusion using pigtail probe

PURPOSE

To report the effectiveness and outcomes of a new technique using the pigtail probe in the treatment of congenital or acquired punctal occlusion.

METHODS

In a retrospective study, 5 patients with punctal occlusion who had undergone punctoplasty and silicone tube intubation using a pigtail probe were reviewed. The authors probed the normal punctum with a pigtail probe and progressed until the pigtail probe had tented into the occluded punctal area. The tented area was then incised with a no. 11 blade tip or penetrated by pushing the pigtail probe itself. The authors then inserted a silicone tube to prevent recurrence of punctal occlusion.

RESULTS

In all 5 patients, the occluded punctum was successfully reopened with this method. Four months after the operation, the silicone tube was removed and the punctum remained patent thereafter. Additionally, lacrimal drainage through the punctum remained intact and symptomatic tearing improved in all 5 patients.

CONCLUSIONS

Punctoplasty using the pigtail probe seems to be a safe and effective method for identifying and repairing occluded puncta.

Long-Term Success of Modified External Dacryocystorhinostomy for the Treatment of Distal Common Canalicular Block

PURPOSE

Epiphora caused by common canalicular obstruction is difficult to manage. Distal common canalicular block caused by membranous obstruction near its junction with the lacrimal sac can be managed by modified dacryocystorhinostomy (DCR) consisting of internal membranectomy. We report our experience with this technique during long-term follow-up.

DESIGN

A prospective interventional case series was performed at a tertiary care center including 15 patients with a diagnosis of distal common canalicular obstruction.

METHODS

External DCR was performed, and after lacrimal sac opening, membranous obstruction at the distal end of the common canaliculus was identified and managed successfully in all cases. Mitomycin C was applied, and silicone intubation was done for 2 months. The main outcome measures were anatomical success (patent syringing) and functional success (complete relief of epiphora) at a minimum follow-up period of 1 year.

RESULTS

Fourteen (93%) cases were completely relieved of epiphora with patent lacrimal syringing at a mean follow-up of 15.4 months (P = 0.0001, McNemar test). The postoperative complications occurred in 4 cases and included nasal bleeding, lateral displacement of silicone tube at medial canthus, complete extrusion of silicone tube (at 4 weeks), and noticeable incisional scar.

CONCLUSIONS

Distal common canalicular obstruction can be successfully managed with DCR with internal membranectomy and silicone intubation with mitomycin C. It avoids excision of common canaliculus as compared with canaliculo-DCR. The procedure is safe and effective with minor complications.