Nasolacrimal polyurethane stent placement for epiphora: technical long-term results

Nasolacrimal stent with shape memory as an advanced alternative to silicone products

Epiphora is the overflow of tears typically caused by obstruction or occlusion of the nasolacrimal duct. More attention is required to address this global health issue owing to the increase in air pollution. Implantation of a silicone stent is the preferred treatment for epiphora; however, introducing a silicone stent into a narrow duct with complex geometry is challenging as it requires guidance by a sharp metal needle. Additionally, silicone can cause adverse reactions such as biofilm formation and tear flow resistance due to its extreme hydrophobicity. To overcome these problems, in this study we developed a new type of biocompatible shape memory polymer (SMP) stent with elasticity capacity for self-expansion. First, SMPs in the form of x%poly(ε-caprolactone)-co-y%poly(glycidyl methacrylate) (x%PCL-y%PGMA) were synthesized via ring opening polymerization by varying the molar ratio of PCL (x%) and PGMA (y%). Second, the shape memory and mechanical properties were tuned by controlling the crosslinking degree and concentration of x%PCL-y%PGMA solution to produce a test type of SMP stent. Lastly, this 94%PCL-06%PGMA stent exhibited more standout critical functions in a series of in vitro and in vivo experiments such as a cell growth-supporting level of biocompatibility with nasal epithelial cells without significant inflammatory responses, better resistance to biofilm formation, and more efficient capacity to drain tear than the silicone control. Overall, 94%PCL-06%PGMA can be suggested as a superior alternative to the currently used materials for nasolacrimal stents. STATEMENT OF SIGNIFICANCE: Silicone intubation (stenting) has been widely used to treat nasolacrimal duct obstruction, however, it can cause adverse clinical effects such as bacterial infection; presents procedural challenges because of the curved nasolacrimal duct structure; and shows poor drainage efficiency stemming from the highly hydrophobic nature of silicone. In this work, we describe an innovative shape memory polymer (SMP) as a superior alternative to conventional silicone-based materials for nasolacrimal duct intubation. We demonstrate the clear advantages of the SMP over conventional silicone, including a much higher drainage capacity and superior resistance to bacterial infection.

Endoscopic endonasal dacryocystorhinostomy with ostial stent intubation following nasolacrimal duct stent incarceration

PURPOSE

To study the feasibility of endoscopic endonasal dacryocystorhinostomy (EE-DCR) with novel lacrimal ostial stent (LOS) intubation for patients with chronic dacryocystitis with incarceration of a previously implanted nasolacrimal duct stent (NDS).

METHODS

According to surgical procedure, 166 patients (167 eyes) were divided into two groups: EE-DCR with LOS intubation was performed on 126 patients (127 eyes) in the EE-DCR group; while external dacryocystorhinostomy (E-DCR) with silicone tube intubation was performed on 40 patients (40 eyes) in the E-DCR group. The LOS or silicone tube was retained for 3-6 months. All patients were followed up for 12-36 months. Success rate of tear drainage reconstruction (TDR) and complications were retrospectively compared.

RESULTS

Excluding patients with early detachment of the LOS or the silicone tube, or with incomplete follow-up period, 117 patients (117 eyes) in the EE-DCR group and 36 patients (36 eyes) in the E-DCR group were included. The mean surgical time was 45.8 ± 11.5 min in the EE-DCR group and 68.1 ± 23.8 min in the E-DCR group (p < 0.001). Intraoperatively, the lacrimal sac was observed to become very small and its walls were thin, hyperemic and fragile, firmly attaching to the NDS by fibrous bands in all eyes. Upon final review, success rate of TDR was 83.8% (98/117) in the EE-DCR group, while 58.3% (21/36) in the E-DCR group (p < 0.01). Failure of TDR due to ostial closure by excessive fibrosis occurred in 14 out of 19 patients in the EE-DCR group, significantly less than the 11 out of 15 patients with failed TDR in the E-DCR group (χ(2 )= 6.959, p < 0.01). No significant difference existed in failures due to granuloma occluding the ostium or common canaliculus obstruction.

CONCLUSION

EE-DCR with LOS intubation may be an effective procedure to manage the special subgroup of patients with chronic dacryocystitis with incarcerations of a previously implanted NDS.

A novel technique to recanalize the nasolacrimal duct with endodiathermy bipolar probe

Aims:

To evaluate a new approach for recanalization (RC) of nasolacrimal duct obstruction in the treatment of the symptomatic nasolacrimal duct obstruction (NLDO).

Materials and Methods:

A prospective, interventional, comparative study in 302 eyes of 209 patients of symptomatic nontraumatic NLDO. Eyes with previous failed surgery were excluded. One hundred and fifty-one eyes underwent RC with 20 G endodiathermy bipolar probe connected to a 7 W diathermy followed by bicanalicular intubation under direct visualization. One hundred and fifty-one eyes underwent standard external dacryocystorhinostomy (DCR). Follow-up was for 24 months and evaluation was done on basis of change in symptoms and lacrimal syringing. Data was analyzed by Chi-square test and unpaired t-test. P value < 0.05 was considered statistically significant.

Results:

Success defined as an asymptomatic patient or freely patent syringing was 92.7% (140 eyes) in RC group and 83.44% (126 eyes) in DCR group. Success was significantly more (P ≤ 0.01) in RC than DCR group. Surgical time was significantly less in RC than DCR (P ≤ 0.001). In RC group, RC could not be performed in three eyes and had to be later taken up for DCR. Intubation after RC was not achieved in four eyes; however these eyes had a patent pathway till 24 months. Twenty-two eyes had a premature extrusion of the tube; but the success rate in these (20 eyes) was comparable to the others within the group (P > 0.05). Two eyes in RC and one in DCR group had complications.

Conclusions:

RC with 20 G endodiathermy bipolar probe is a quick, simple, and effective alternative to standard external DCR.

Treating epiphora in adults with the Wilhelm plastic nasolacrimal stent: mid-term results of a prospective study

The objective of the present study was to evaluate, in a prospective, single-center study, the effectiveness of the Wilhelm-type stent used in interventional radiology for the management of epiphora. Patients (n = 104; mean age 64 [range 25–88]; 33 male and 71 female) with severe epiphora had the stents inserted (135 stents in 115 eyes) to treat obstruction of the nasolacrimal system. The etiology of the obstruction was idiopathic in 83 cases, chronic dacryocystitis in 31, cases and postsurgical status in 1 case. The overall technical success rate of stent placement was near 94%. Resolution of epiphora was complete in 105 cases and partial in 3 cases. During a mean 13-month follow-up (range 1 week to 28 months), the median duration of primary patency was 11 months, and the percentage of patency at 6 months was 60.8%, at 1 year was 39.6%, and at 2 years was 25%. Stents malfunctioned in 54 cases, and all were easily withdrawn except in 1 case. Of these 27 cases, patency recovered spontaneously in 9 and by way of a second stent in 18. Secondary patency was 50%. Factors presdisposing to lower primary patency are inflammatory etiology and location of the obstruction. The benefit of stent deployment is clear with respect to the resolution of epiphora in candidate patients for percutaneous treatment. Technical and/or design improvements would be welcomed.

Randomized comparison of nasolacrimal cryoplasty versus plastic lacrimal stenting in the management of epiphora in adults

PURPOSE

To evaluate the efficacy of plastic polyurethane stents compared with nasolacrimal cryoplasty in the management of epiphora in adults.

MATERIALS AND METHODS

Patients (N = 37; mean age, 64 years; range, 34-86 y; six men, 31 women) with severe epiphora with partial/complete obstruction of the nasolacrimal system were randomized to have a plastic stent inserted (n = 19) or to undergo balloon dilation cryoplasty (n = 18). Both procedures were conducted on an outpatient basis. Patency was assessed with Kaplan-Meier curves.

RESULTS

Initial technical success rate and immediate resolution of epiphora was complete in all cases. At 6 months of follow-up, outcomes were already significantly different between the treatment groups and hence the study was discontinued. Plastic stent placement achieved a primary patency rate of 59.6% at 6 months, compared with 12.4% in the cryoplasty group (P < .0004). Multivariate analysis indicated that other measured variables (sex, age, etiology, previous treatment, and the interventional radiologist's expertise) had no significant effect on the outcomes (P > .05).

CONCLUSIONS

Initial success was good in both treatment groups, with nasolacrimal plastic stent placement achieving a level of primary patency superior to the cryoplasty procedure for the relief of epiphora on short-term follow-up. However, long-term outcome evaluation is needed before stent placement can be recommended as an alternative to more established surgical procedures.

Nasolacrimal stenting: toward improving outcomes with a simple modification of the song stent

The purpose of this study was to evaluate, in a prospective, single-center study, the effectiveness of Song's polyurethane stents, modified "in-house," in the percutaneous management of epiphora. Patients (n = 170; age range 18-83, mean = 64; 50 male, 120 female) with severe epiphora had the modified stents inserted (183 eyes/195 stents) to treat unilateral/bilateral and complete/partial obstruction of the nasolacrimal system. The etiology of the obstruction was idiopathic in 119 cases (61%) and chronic dacryocystitis in 76 (39%). The set designed by Song was used in all patients but modified by us such that the extreme end is cone-shaped. The original technique was slightly modified by us and the procedure was conducted on an outpatient basis. The initial technical success rate of stent placement was 97%. Resolution of epiphora was complete in 180 eyes and partial in 3. On follow-up (mean = 18 months; range: 2 days to 24 months), 165 of 195 stents (85%) remained patent. Primary patency rates at follow-up were 86%, 84%, 84%, and 79% in the first 6 months, second and third 6 months, and the present (24 months), respectively. Stents became obstructed in 30 patients, but all but 2 were easily withdrawn and 20 of these patients remained asymptomatic for a mean of 14 months (secondary patency of 67%). Following stent removal, the withdrawn stent was replaced with a new stent in the same intervention on 14 occasions. In another six cases, patency was re-established without the need of a second stent. The procedure is simple and safe, both in stent insertion as well as in mechanical de-blocking and withdrawal when occluded. Success was >80 % in the short term (1-year follow-up). Stenting failure does not preclude other treatment because with the modification that we had introduced, the extreme end of the stent becomes more accessible to mechanical de-blocking, withdrawal, and relocation. The levels of primary and secondary patencies are promising and warrant more extensive investigation.

Evaluation of Polyurethane Nasolacrimal Duct Stents: In Vivo Studies in New Zealand Rabbits

The purpose of this study was to evaluate the radiographic and biological effects of different polyurethane nasolacrimal duct stents in an animal model. Fifteen polyurethane nasolacrimal duct stents (n = 5 mushroom-type stents, n = 5 newly designed S-shaped TearLeader stents without hydrophilic coating, and n = 5 S-shaped TearLeader stents with hydrophilic coating) were implanted in the nasolacrimal ducts of eight unaffected New Zealand rabbits. One nasolacrimal system served as control. Clinical and radiographic follow-up was performed at 1-, 2-, and 4-week intervals, then after a 3-month interval, after which the animals were euthanized. All stents were implanted without major periprocedural complications. The stents proved to be patent by the end of the procedure. During follow-up, all mushroom-type stents were occluded at 4 weeks. None of these stents opened to forced irrigation. Clinically, all rabbits demonstrated severe dacryocystitis. Three out of five TearLeader stents without hydrophilic coating were blocked at 4 weeks; one out of five was open to irrigation. Best results were observed in the stent group with hydrophilic coating. Follow-up dacryocystography demonstrated patent stents in nasolacrimal ducts of all animals after 4 weeks. In only one of five cases, the coated stent became partially occluded after 2 months. These animals were free of clinical symptoms. After 3 months, at least three out of five stents still opened to forced irrigation and only one stent was completely blocked. Dislocation of the stents was not observed. Refinement of the stent surface and stent design improves the results of nasolacrimal duct stenting in this animal model. Implantation of hydrophilic-coated S-shaped stents is highly superior to conventional mushroom-type stents and noncoated stent types. Hydrophilic coating seems to prevent foreign-body reactions, resulting in maximized stent patency.

Nasolacrimal stents for the treatment of epiphora: technical problems and long-term results

PURPOSE

To evaluate the long-term effectiveness of nasolacrimal stents for the treatment of obstructive epiphora, and the complications related to the procedure.

METHODS

This study is a non-randomized prospective clinical trial. Eighty-five patients underwent fluoroscopally-guided placement of polyurethane stent in 86 lacrimal systems for the treatment of severe idiopathic obstructive epiphora. The sites of obstruction were: sac-duct junction (n = 65), sac (n = 10), and nasolacrimal duct (n = 11). The procedure was performed in an outpatient basis under local anesthesia. Patients were followed for a mean of 24 months (1-84) with clinical examinations and/or dacryocystography. Clinical success was defined as symptoms resolution or improvement, and the patency of the lacrimal system to irrigation.

RESULTS

Stent placement was technically successful in 76 (88.4%) eyes. Technical failures (11.6%) were caused by inability to pass the guide-wire through the lacrimal system. Immediate complications occurred in 19 (22%) eyes, were mild and included: self-limited epistaxis (7), mild palpebral hematoma (7), moderate pain (3), lacrimal puncta bleeding (1), palpebral emphysema (1), and false passage (1). Of the 76 inserted stents, 33 (43.4%) became occluded, and 43 (56.6%) remained patent after a mean of 24 months. Mean duration of stent patency was 38 months. Clinical success was achieved in 40 (52.6%) of the successfully implanted stents.

CONCLUSIONS

The procedure is well tolerated and can be performed on an outpatient basis. Patency decreases with follow-up, and, in the long-term, the success rate is inferior to that achieved by external dacryocystorhynostomy. However, it many be considered as a valid alternative to surgery in selected patients.

Clinicopathologic findings after nasolacrimal polyurethane stent implantations

PURPOSE

To evaluate the results of nasolacrimal polyurethane stent implantations for the treatment of primary acquired nasolacrimal duct obstruction, and to determine the effects of various surgical procedures, including stent removal, in subsequent nasolacrimal duct obstruction.

METHODS

This study included 15 patients who had nasolacrimal polyurethane implantations for the treatment of primary acquired nasolacrimal duct obstruction. Occluded stents were removed either by nasal endoscopy or during dacryocystorhinostomy (DCR). Cultures and biopsies were performed on the removed stents, and the results of the secondary DCR were analyzed for a 6-month follow-up period.

RESULTS

During stent removal surgery, various degrees of chronic inflammatory reaction and fibrous tissue formation were detected in the lacrimal sac and nasolacrimal duct. Formations of granuloma and fibrous tissue were found in 15 eyes, and culture-positive reaction were found in nine of the 15 eyes. Conventional dacryocystorhinostomy surgery was performed in nine of the 15 eyes and a silicone tube was located at the canaliculi. Subjective and objective outcome were favorable in 13 of the 15 eyes.

CONCLUSIONS

The success rate of nasolacrimal polyurethane stent implantation for the treatment of primary acquired nasolacrimal duct obstruction is low. This may result from a chronic inflammatory reaction. Despite the low success rate of nasolacrimal polyurethane stent implantation, the success rate of endonasal DCR as a subsequent surgery is favorable.

Polyurethane stents for lacrimal duct stenoses: 5-year results

PURPOSE

To present 5-year results of polyurethane stent implantation for treatment of postsaccal lacrimal duct stenoses.

METHODS

Ninety-two consecutive patients admitted to our hospital for stent implantation between 1997 and 2001 were retrospectively analysed. The patients who were not re-treated in our clinic were asked by questionnaire about their satisfaction and complaints.

RESULTS

In 5 patients (5.4%) the implantation was not completed, 38 patients (41.3%) were re-treated due to relapsing epiphora during follow-up, and 11 stents (12.0%) were removed by dacryocystorhinostomy (DCR). Five stents (5.4%) were extracted transnasally. Four stents (4.3%) were removed in another hospital. Eighteen patients (19.6%) had relapsing epiphora but have not been re-treated so far. Forty-nine of 92 patients (53.3%) were not re-treated in our clinic and were interrogated by means of a questionnaire. Twenty-seven answered (55.1%), 8 did not answer (16.3%) and 14 patients (28.6%) did not receive the letter because they had moved away or died. Only 12 of the patients who answered the questionnaire had no or slight complaints (44.4%, or 18.5% of all treated patients).

CONCLUSIONS

The long-term success rate of polyurethane stent implantation is very low (18.5%).

Interventional radiology in the lacrimal drainage system

This article presents a review of the interventional radiological procedures in the lacrimal drainage system. Balloon dacryocystoplasty and nasolacrimal polyurethane stent placement are the main fluoroscopically guided interventions for the treatment of epiphora by recanalizing the obstructed LDS. These procedures can also be used for dacryolith removal and lacrimal sac abscess treatment.

Outcome of Patients with Nasolacrimal Polyurethane Stent Implantation: Do They Keep Tearing?

PURPOSE

To evaluate the results of nasolacrimal polyurethane stent implantation for the treatment of primary acquired nasolacrimal duct obstruction and the effects of obstructed nasolacrimal stent on subsequent dacryocystorhinostomy (DCR).

METHODS

This study was designed as a nonrandomized, prospective clinical trial. Stent implantation was attempted in 53 obstructed lacrimal drainage systems of 47 patients. Stent placement was performed in a retrograde fashion through the external nare over a guide wire, which was introduced from the upper punctum. Occluded stents were removed either with nasal endoscopy or during DCR. External DCR surgery with silicone intubation was performed in cases with stent failure.

RESULTS

The mean follow-up period was 23.4 months. The success rate of stent implantation was 60.4%, 37.5%, and 31.2% at 6-, 12-, and 18-month follow-up, respectively. Stent obstruction developed in 33 eyes. Twenty underwent external DCR with silicone intubation. During DCR surgery, varying degrees of chronic inflammatory reaction were detected in the lacrimal sac and nasolacrimal duct. The mean follow-up period after DCR was 10.3 months. Epiphora was relieved with DCR in all but one eye.

CONCLUSIONS

The success rate of nasolacrimal polyurethane stent implantation for the treatment of primary acquired nasolacrimal duct obstruction is low and may induce inflammation and fibrous tissue formation. Although this may cause further difficulties in subsequent lacrimal surgery, epiphora could be relieved with meticulous technique.

Resolution of Epiphora with Nasolacrimal Stents: Results of Long-term Follow-up in a Multicenter Prospective Study

PURPOSE

To evaluate in a prospective, multicenter setting the long-term effectiveness of polyurethane stents in the percutaneous management of epiphora.

MATERIALS AND METHODS

Patients (n = 426; age range, 19-88 years, mean, 48; 91 men, 335 women) with severe epiphora had stents (470 eyes/496 stents) inserted to treat unilateral or bilateral and complete or partial obstruction of the nasolacrimal system. The etiology of the obstruction was idiopathic in 280 cases (59.5%) and chronic dacryocystitis in 190 (40.4%). The stent set designed by Song was used in all patients, and the original technique was slightly modified by us and conducted on an outpatient basis.

RESULTS

The initial technical success rate of stent placement was 95%. The average time of the procedure was 6 minutes (range, 3-70). Resolution of epiphora was complete in 452 eyes and partial in 18. On follow-up (mean, 24 months; range, 1 week to 67 months), 340 of 496 stents remained patent (68.5%). Segregating primary patency by year of follow-up, the rates were 75.6%, 68.4%, 64.8%, 60.1%, and 59.2% in the first, second, third, fourth, and the current (67 months) years, respectively. Minor complications such as moderate pain (21 cases), epistaxis (75 cases), palpebral edema and hematoma (31 cases), and headache (four cases) and two acute dacryocystitis events were recorded. Of the 156 obstructed stents, 114 were withdrawn, and 49 of these patients remained asymptomatic for a mean of 27 months (secondary patency, 31.4%). After stent removal, the sac configuration was unchanged in 93 (81.5%), contracted in 11 (9.6%), and widened in 10 (8.8%) cases.

CONCLUSIONS

The procedure is simple and safe, both in stent insertion and in withdrawal when occluded. The success rate was >75% in the short term and >55% in the long term. Although not totally without concerns, the technique is attractive for most patients who prefer not to undergo surgery or are unsuitable surgical candidates. Stent failure does not preclude subsequent treatment options and is an excellent first-line treatment of epiphora.

Treatment of Complete Obstruction of the Nasolacrimal System by Temporary Placement of Nasolacrimal Polyurethane Stents: Preliminary Results

AIM

To assess the efficacy of the temporary placement of polyurethane nasolacrimal stents as a treatment for complete post-saccal obstruction of the lacrimal apparatus.

MATERIALS AND METHODS

Polyurethane nasolacrimal stents were inserted under radiological guidance in nine patients with grade IV epiphora due to complete obstruction of the lacrimal system, at the junction of the lacrimal sac and duct (eight patients) or in the lacrimal duct (one patient). On average, the stents were removed 4 months (range: 3-6 months) after insertion. Dacryocystography was performed immediately before and after each stent was removed. Subsequently, periodic clinical and radiological examinations were performed until recurrence of the epiphora, at which point follow-up concluded.

RESULTS

All patients remained free of epiphora and clinical inflammation while the stents were in place, but re-obstruction of the lacrimal system occurred in all patients less than 2 months after the stents were removed. Adhesion of three stents to the lacrimal tract was observed upon removal. In seven cases the dacryocystography results at the end of follow-up revealed changes in the configuration of the lacrimal apparatus.

CONCLUSION

Based on our preliminary experience, temporary placement of polyurethane stents would not appear to be an efficacious therapeutic option for treating epiphora caused by post-saccal obstruction.

Obstruction of the lacrimal system: treatment with a covered, retrievable, expandable nitinol stent versus a lacrimal polyurethane stent

PURPOSE

To compare the clinical effectiveness of a covered nitinol stent with that of a polyurethane stent for treatment of lacrimal system obstructions.

MATERIALS AND METHODS

A nitinol stent was knit from a single thread of 0.1-mm nitinol wire in a tubular configuration and was covered by dipping the stent into a polyurethane solution. The stent was 4 mm in diameter and 30 or 35 mm long. With fluoroscopic guidance, a covered nitinol stent (n = 33, group A) or a polyurethane stent (n = 35, group B) was placed in 68 patients. The following items were evaluated retrospectively: technical success, procedure time, cumulative patency rate, and complications. An unpaired Student t test was used to analyze the difference between the procedure times. Kaplan-Meier survival curves and a log-rank test were used to compare the cumulative patency rates.

RESULTS

Stent placement was technically successful in 31 (94%) of 33 patients in group A and in all 35 (100%) patients in group B. After stent placement, all patients showed resolution of epiphora. Average procedure time was 400 seconds (range, 270-900 seconds) in group A and 260 seconds (range, 150-900 seconds) in group B. The difference between the procedure times was statistically significant (P =.0003). During the mean follow-up period of 40 months, there was recurrence of epiphora in 30 of 31 patients in group A and 26 of 35 patients in group B. The difference of the cumulative patency rates was statistically insignificant (P =.2).

CONCLUSION

Although the polyurethane stent used for treatment seemed to be more effective than the nitinol stent, selection of these stents for placement should be made with caution, because the long-term patency rates are not encouraging.

Obstruction of the lacrimal drainage system

This review covers evolving concepts in lacrimal outflow obstruction. Recent studies have increased our understanding of the surgical anatomy and pathophysiology of the lacrimal drainage system through radiologic, clinical, and microbiologic techniques. While external dacryocystorhinostomy remains an important treatment for nasolacrimal duct obstruction, there have been a number of therapeutic developments worthy of review, including advances in endoscopic and transcanalicular dacryocystorhinostomy, conjunctivodacryocystorhinostomy, and the use of mitomycin C in these procedures. In addition, we summarize recent advances in minimally invasive techniques for lacrimal outflow obstruction, including balloon dacryocystoplasty, lacrimal stents, and conjunctivoplasty. Finally, the roles of probing versus irrigation, nasal endoscopy, and endoscopic dacryocystorhinostomy in children are discussed.

Treatment of nasolacrimal duct obstruction with polyurethane stent placement: long-term results

OBJECTIVE

The purpose of this study was to evaluate the long-term efficacy of polyurethane stent placement in adults with nasolacrimal duct obstruction.

SUBJECTS AND METHODS

Polyurethane stents were placed under fluoroscopic guidance in 52 eyes of 49 patients (mean age, 43 years) with severe epiphora due to idiopathic nasolacrimal duct obstruction. The obstruction was complete in 44 eyes and partial in eight. Clinical success was defined as complete resolution of or great improvement in the symptoms of epiphora and the patency of the lacrimal system to irrigation. Mean follow-up was 23 months (range, 14-44 months).

RESULTS

Stent placement was technically successful in 50 eyes (96%). The mean fluoroscopy screening time was 2.2 min (range, 0.2-5.8 min). Two patients were lost to follow-up. Clinical success was obtained in 33 (69%) of 48 eyes. Lacrimal symptoms developed in 23 (70%) of these 33 eyes at least once during the follow-up, but these patients responded well to topical drug treatment and lacrimal irrigation. External dacryocystorhinostomy was performed in 13 eyes after failure of the stents. At surgery, lacrimal sacs were shrunken, hyperemic, and fragile in all eyes, making it difficult to anastomose with nasal mucosa. Histologic examination showed granulation tissue and chronic inflammation of the sac epithelium.

CONCLUSION

The success rate of the nasolacrimal stent decreases as follow-up lengthens. After stent treatment, lacrimal symptoms frequently develop, even if the stent remains patent, and require multiple office visits and therapy. The polyurethane stent may induce a chronic inflammatory response in the lacrimal sac, which can interfere with subsequent dacryocystorhinostomy.

Nasolacrimal stents in the treatment of epiphora: long-term results

PURPOSE

Assessment of the long-term results achieved with use of nasolacrimal stents in the treatment of epiphora caused by obstruction of the lacrimal apparatus. The role of stents in treating this condition is evaluated.

MATERIALS AND METHODS

From February 1997 to April 1999, a total of 89 procedures to insert nasolacrimal stents were performed in 77 patients (20 men, 57 women; mean age, 53 years). A total of 79 stents were successfully implanted, with 10 failures (11.2%). Postprocedural course was followed for 16-38 months (mean, 27 mo) by means of clinical examinations and/or periodic dacryocystography, with removal of occluded stents. On conclusion of the study in September 2000, dacryocystography was performed in all patients in whom stents were still in place.

RESULTS

Of the 79 stents deployed, two were lost, two had to be excluded from the study, 45 (60%) ceased to function, and 30 (40%) remained patent. Median duration of stent patency of these 79 stents was 20 months. Mean time to occlusion was 9.2 months for all obstructed stents; 4.4 months for improperly placed stents (via a trajectory outside the normal lacrimal drainage apparatus) and 12.2 months for stents that appeared to have been inserted properly. Of the 45 occluded stents, 40 were removed and five were left in place. Upon removal, adherence of the stents to the lacrimal apparatus was frequently observed.

CONCLUSIONS

The low patency rate and the difficulties encountered in removing nasolacrimal stents during the course of long-term placement calls into question the efficacy of this method as a definitive treatment for epiphora caused by obstruction of the lacrimal drainage system, although studies comparing this and other treatment modalities are needed. Assessment of temporary stent placement may be in order.