Complete obstruction of the nasolacrimal system. Part II. Treatment with expandable metallic stents

The role of interventional radiology in the treatment of epiphora

Epiphora is a relatively common ophthalmologic affection representing almost 5% of clinical consultations in ophthalmology and it consists in the complete or partial obstruction of nasolacrimal duct, leading to insufficient drainage of tears. The traditional treatment is represented by surgery namely, external dacryocystorhinostomy (DCR). Despite the high success rate DCR has many disadvantages and limitations since it requires general anesthesia, it may arise in a permanent facial scar and it is often affected by the reobstruction of the anastomotic tract by fibrotic scars and osteogenic activity. Fluoroscopically guided interventional procedures are a therapeutic alternative to surgery for lacrimal duct system obstructions that can consist either in balloon dacryocystoplasty or in nasolacrimal stent placement. In both cases, a pre-operative imaging characterization of the occlusion is needed for a correct treatment planning. In this review, we propose to highlight the role of interventional radiology in the treatment of epiphora and the role of computed tomography dacryocystography (CTD) in depiction and the pre-interventional planning.

Efficacy of endoscopic lacrimal duct recanalization using microendoscope

PURPOSE

To describe a new endoscopic procedure to restore the passage of tears in an obstructed lacrimal drainage system and to compare its efficacy with the standard external dacryocystorhinostomy (SE-DCR).

METHODS

Patients with complete and partial primary acquired nasolacrimal duct obstruction (PANDO) were randomly allocated to 2 treatment groups using completely randomized design. The first group was treated using endoscopic lacrimal duct recanalization (ELDR), while the second group was treated using SE-DCR. Follow-up was conducted for at least 6 months and evaluated for anatomical and functional patency. Complications were also noted for both groups.

RESULTS

A total of 86 patients underwent ELDR, 60 of whom had complete PANDO, while 26 patients had partial PANDO. Eighty patients underwent SE-DCR; 58 had complete PANDO, and 22 had partial PANDO. The combined success rate in terms of anatomical patency for ELDR was 93.02% (95% confidence interval [CI], 0.88-98) compared with 93.75% (95% CI, 0.87-90) for SE-DCR (p = 0.85). Meanwhile, the combined success rate (functional patency) for ELDR is 84.88% (95% CI, 0.77-93) versus 90.00% (95% CI, 0.83-97) for SE-DCR (p = 0.32).

CONCLUSIONS

ELDR using microendoscope is as efficacious as SE-DCR, without its associated major complications.

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.

Treatment of lacrimal stenoses obstructions with interventional radiology: immediate and 5-year follow-up results

PURPOSE

This study was undertaken to evaluate the effectiveness of the Song stent in patients with nasolacrimal duct obstruction.

MATERIALS AND METHODS

Between 2003 and 2007, we treated 76 consecutive nasolacrimal obstructions in 73 patients (mean age 56 years; range 19-81) with implantation of polyurethane stents. Indications were epiphora in 46 patients, dacryocystitis in 18 and recurrent conjunctivitis in three. Average follow-up was 1 year (3 months to 5 years).

RESULTS

Technical success was achieved in 73 procedures (96%). Complications included pain in three cases, eyelid inflammation in four cases and severe bleeding in one case. Postprocedural mucocele was observed in five patients. Mean time without symptoms was 31 weeks. There were 24 cases of stent obstruction: 15 were treated with high-pressure 5% N-acetyl-cysteine and saline flush, achieving resolution in two cases; in three cases, attempts to recanalise the obstruction with a guidewire failed. The occluded stents were rsemoved in 22 patients: seven remained asymptomatic, 15 had recurrence of epiphora, nine received a new stent after dacryocystography and six underwent dacryocystorhinostomy.

CONCLUSIONS

Advantages of the procedure include the lack of anatomical alterations to the lacrimal ducts and a low short-term complication rate, whereas limitations include restricted duration of stent patency. The pathophysiological causes of stent obstruction should be clarified in order to relate them to stent morphology.

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.

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.

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.

Nonsurgically placed nasolacrimal stents for epiphora: long-term results and factors favoring stent patency

PURPOSE

To evaluate long-term effectiveness of a polyurethane stent in lacrimal system treatment.

MATERIALS AND METHODS

Fluoroscopically guided placement of a polyurethane lacrimal stent was evaluated in 727 obstructed lacrimal systems in 588 patients with a mean follow-up period of 77 weeks (range, 1-277 wk), from which the technical and initial success rates and long-term patency were calculated. The impact of factors affecting long-term patency, including symptom duration, previous probing, presence of pus or eye discharge, lesion multiplicity, and site of obstruction were evaluated. Changes in 295 patients' lacrimal sac configuration after stent removal were analyzed and classified into three categories: contraction, widening, and no change.

RESULTS

The overall technical success rate in this study was 95.9%, with a 90.8% initial clinical success rate. The median primary patency duration was 504.33 days plus minus 23.17; secondary median patency duration was 642.87 days plus minus 24.68. Most favorable factors such as symptom duration, previous probing, presence of pus, or eye discharge showed no significant difference; however, site of obstruction and lesion multiplicity influenced mean patency. Lesions below the junction and single lesions showed longer patency periods. Common canalicular obstruction after stent removal occurred in 50 (17%) lacrimal systems. Irregular sac configuration appeared in 171 (58%) lacrimal systems after stent removal. Sac configuration was the same in 185 (62.7%) lacrimal systems, contracted in 105 (35.6%), and widened in five (1.7%). In 151 eyes of 295, epiphora recurred 121.6 days (range, 1-1,182 d) after stent removal.

CONCLUSION

Fluoroscopic lacrimal stent placement is a simple and safe outpatient procedure, but high recurrence and sac irregularities after stent removal are not encouraging.

Nasolacrimal stents in the management of epiphora: medium-term results of a multicenter prospective study

PURPOSE

To evaluate in a prospective multicenter setting the clinical utility of polyurethane stents in the percutaneous management of epiphora.

MATERIALS AND METHODS

Patients (N = 163; age range = 22-85 y, mean = 52 y; 29 men, 134 women) with severe epiphora had stents (n = 183) inserted under fluoroscopic guidance in 180 lacrimal systems (unilateral = 146; bilateral = 17) to treat complete (n = 172) or partial (n = 8) obstruction of the nasolacrimal duct or sac. The junction between sac and duct was the most frequent location (n = 102), followed by the sac alone (n = 48), and the duct alone (n = 30). The etiology of the obstruction was idiopathic in 113 cases (63%) and chronic dacryocystitis in 67 (37%). The set designed by Song was used in all patients and the original technique was slightly modified by the authors. All patients were treated on an outpatient basis. Average time of the procedure was 14 minutes (range = 3-70 min).

RESULTS

Initial technical success rate of stent placement was 97%. Resolution of epiphora was complete in 175 eyes and partial in five. On follow-up (mean = 450 d; range = 8-730 d), 157 of 183 stents remained patent (85.8%). Of the 24 obstructed, 19 were easily withdrawn and 17 of these patients remained asymptomatic for a mean of 15 months (secondary patency rate = 89.5%).

CONCLUSIONS

The procedure is simple and safe. It can be performed on an outpatient basis and the original technique could be improved with some technical modifications. It is well tolerated by patients and may be considered as a valid alternative technique for the resolution of epiphora.

Balloon dacryocystoplasty study in the management of adult epiphora

PURPOSE

To determine the efficacy of dacryocystoplasty with balloon dilation in the treatment of acquired obstruction of the nasolacrimal system in adults.

METHODS

Balloon dacryocystoplasty was performed in 52 eyes of 42 patients under general anaesthetic. A Teflon-coated guidewire was introduced through the canaliculus and manipulated through the nasolacrimal system and out of the nasal aperture. A 4 mm wide 3 cm coronary angioplasty balloon catheter was threaded over the guidewire in a retrograde fashion and dilated at the site of obstruction.

RESULTS

There was complete obstruction in 30% of cases and partial obstruction in 70%. The most common site of obstruction was the nasolacrimal duct. The procedure was technically successful in 94% of cases. The overall re-obstruction rate was 29% within 1 year of the procedure. There was an anatomical failure rate of 17% for partial obstruction and 69% for complete obstruction within 1 year.

CONCLUSIONS

Balloon dacryocystoplasty has a high recurrence rate. There may be a limited role for this procedure in partial obstructions. Further refinements of the procedure are necessary before it can be offered as a comparable alternative to a standard surgical dacryocystorhinostomy.

Nasolacrimal polyurethane stent placement: preliminary results

PURPOSE

To present our initial results in the treatment of nasolacrimal obstruction by placing a polyurethane stent.

METHODS

74 nasolacrimal stents were implanted under fluoroscopic guidance in obstructed nasolacrimal systems of 64 patients. Dacryocystography and CT were used to verify the position and patency of the stents. Mean follow-up was 15 months. Clinical examinations were done at the first week, first month, third month and sixth month after stent placement.

RESULTS

Polyurethane stents were successfully inserted and permeable in 59 patients (92.1%), but could not be inserted in 5 patients (7.8%). Epiphora was solved and permeable in 53 cases (82.8%), it was not permeable but asymptomatic in 2 cases (3.1%), and was not permeable but symptomatic in 4 (6.2%). In 5 cases (7.8%) stents remained permeable although patients complained of epiphora.

CONCLUSIONS

Polyurethane stent placement is a non-invasive technique that can replace dacryocystorhinostomy, giving better results and tolerance.

Naso-lacrimal duct balloon dilatation: medium to long term follow-up

AIM

Subjective patient response to nasolacrimal duct balloon dilatation (dacryocystoplasty) for epiphora due to primary acquired nasolacrimal duct obstruction (PANDO), was sought over the medium to long term. The relevant dacryocystograms were reviewed to assess the relationship between treatment outcome and dacryocystographic appearances.

MATERIALS AND METHODS

Sixty-three patients who had, in the preceding 12-month to 8-year period, undergone 102 dacryocystoplasties were sent a postal questionnaire in which subjective response to treatment was requested. Fifty-seven original dacryocystograms were reviewed by the author and the appearances of the lacrimal sacs subjectively assessed.

RESULTS

The results showed that in 31% of respondents (total response 48/63, 76%) dacryocystoplasty was ineffective for treatment of PANDO. Treatment failures did not respond to repeat treatment. Sixty-nine per cent of patients considered themselves either cured or improved by the treatment, with a minimal relapse rate during the period studied. The original dacryocystoplasty appearances were unhelpful in predicting treatment response.

CONCLUSION

Dacryocystoplasty can be expected to relieve or improve epiphora in 69% patients with PANDO, (incomplete obstruction) and favourable response to treatment is durable in the medium to long term. Repeat treatment is not recommended for those who fail to respond, though may be appropriate for cases of temporary response. The technique is safe and well tolerated. McCullough, K. M. (2001). Clinical Radiology56, 13-16.

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

PURPOSE

To assess technical problems related to implantation of a polyurethane stent to treat obstructive epiphora, and to assess the long-term patency of the nasolacrimal system.

MATERIALS AND METHODS

Fluoroscopically guided placement of a polyurethane nasolacrimal stent was performed in 70 obstructed lacrimal systems of 62 patients with grade 3-4 obstructive epiphora. Follow-up was conducted for 1-20 months (average, 11.3 months). The obstruction was at the lacrimal sac in six systems, at the junction between the lacrimal sac and the nasolacrimal duct in 60 systems, and at the nasolacrimal duct in four systems. The cause of the obstruction was idiopathic in all cases but was probably residual to dacryocystitis.

RESULTS

Of these 70 procedures, stent placement was technically successful in 61 systems (87%). On long-term follow-up, 41 (67.2%) stents remained in place, with resolution or clinical improvement, and 18 (29.5%) stents were removed (because of occlusion in 17 systems), with stent malpositioning in the duct in six cases. There were seven cases of malpositioning in all. Statistical analysis was performed to evaluate patency, compare patency in properly positioned stents and malpositioned stents, and establish the relationship between malpositioning and the need for irrigation to maintain stent patency. Of the total 70 stents originally placed, 41 (58.6%) were still in place and functional at long-term follow-up. At 1 year, 73% of properly positioned stents remained patent versus 0% of improperly positioned stents. Median stent patency in the former group was 20 months and was 1 month in the latter group (P = .00002). Eleven percent of properly positioned stents required irrigation versus 57% of incorrectly positioned stents (P = .01).

CONCLUSION

After follow-up for 1 year, recurrence of epiphora brought on by stent obstruction was 28%. Early stent blockage and the need for periodic irrigation may be indicative of malpositioning of the stent.

Treatment of nasolacrimal duct obstruction in adults with polyurethane stent

PURPOSE

To evaluate the efficacy of polyurethane nasolacrimal duct stents in the treatment of epiphora resulting from primary acquired nasolacrimal duct obstruction in adults.

MATERIALS AND METHODS

In 25 patients (21 women and four men with mean age of 44 years, range 20 to 74 years) with nasolacrimal duct obstruction, 28 hollow polyurethane stents designed by Song and associates were placed under fluoroscopic guidance. The obstruction was complete in 20 lacrimal drainage systems and partial in eight. The lacrimal sac size was normal or large on dacryocystogram in all lacrimal drainage systems. A Ritleng probe was introduced through the upper punctum and advanced past the obstruction. A guide wire with a flexible tip was then introduced through the probe, over which the stent was advanced in retrograde fashion and placed into the lacrimal sac and nasolacrimal duct. Clinical success was defined by the demonstration of a completely patent lacrimal drainage pathway through saline irrigation and no or minimal complaint of epiphora.

RESULTS

Stent placement was technically successful in 26 of 28 lacrimal drainage systems (93%). The mean time of fluoroscopy screening was 3.2 minutes (range, 1.4 to 5.8 minutes). The overall success rate was 82% (23 of 28 lacrimal drainage systems). Two stents were completely occluded. In one lacrimal drainage system with minimal epiphora, the stented drainage pathway was partially occluded. The patients were followed up from 4 to 22 months (mean, 7.2 months).

CONCLUSIONS

Retrograde placement of a hollow polyurethane nasolacrimal duct stent is a technique that is simple and well tolerated by patients. This method achieves a high success rate and may be suggested as a nonsurgical procedure for adults with primary nasolacrimal duct obstruction and proper lacrimal sac size. The Ritleng probe facilitates the procedure.

Use of a lacrimal stent retrieval hook in the removal of occluded plastic and expandable metallic lacrimal stents

PURPOSE

To evaluate the clinical usefulness of a stent retrieval hook in the removal of occluded lacrimal stents.

MATERIALS AND METHODS

The hook consisted of an inner hook part and an outer pusher part. Under administration of local anesthetic, the retrieval hook was introduced into the nasal cavity and aimed laterally toward the inferior meatus to grasp the distal end of the stent. After grasping the end of the stent, the sheath was pushed to fully grasp it. After that, the hook was pulled out of the external naris. The retrieval hook was used to remove 267 occluded lacrimal plastic or metallic stents.

RESULTS

Technical success rate was 97% in the removal of plastic stents and 96% in the removal of metallic stents. The causes of technical failure were entrenchment of granulation tissue into the stent in six plastic stents and one metallic stent, and inaccessibility of the hook to the distal tip of the stent in one plastic stent. These eight stents were removed by an otorhinolaryngologist or an ophthalmologist. Epistaxis occurred in six patients, which was controlled by a nasal pack.

CONCLUSIONS

The lacrimal stent retrieval hook seems useful for the removal of occluded stents.

Abscess of the lacrimal sac due to chronic or subacute dacryocystitis: treatment with temporary stent placement in the nasolacrimal duct

Stents were placed temporarily in 10 obstructed lacrimal systems in patients with a chronic or subacute lacrimal abscess that did not respond to conventional antibiotic therapy. In all 10 cases, the abscess was treated successfully. Long-term patency of the lacrimal system was restored in five cases. Temporary stent placement appears to be a promising method to treat a chronic or subacute lacrimal abscess.

Treatment of obstructive epiphora in adults by balloon dacryocystoplasty

AIMS

To determine the efficacy of dacryocystoplasty with balloon dilatation in the treatment of complete and partial obstruction of the lacrimal drainage system.

METHODS

The procedure was performed on 26 patients with epiphora due to complete (n=16) or partial (n=10) obstruction of the lacrimal drainage system. A flexible tipped guide wire was introduced through the superior canaliculus into the inferior meatus and manipulated out of the nasal cavity. A 3 mm balloon was then introduced in a retrograde direction over the guide wire and dilated at the obstruction site.

RESULTS

The procedure was technically successful in all patients with partial obstruction, but unsuccessful in four of 16 cases with complete obstruction. Reobstruction occurred in eight of 12 patients with complete obstruction, and in five of 10 patients with partial obstruction. The overall success rate was 25% for complete and 50% for partial obstructions. The mean follow up was 14 months (8-37 months).

CONCLUSION

Although the balloon dacryocystoplasty is a simple and minimally invasive technique, the outcome from our study indicates that it is not advisable for treatment of complete obstruction of the lacrimal drainage system. Balloon dilatation may prove suitable for the treatment of patients with partial obstruction below the level of the lacrimal sac, especially in those who are poor candidates for surgery, or who do not wish to undertake dacryocystorhinostomy. Even in the partial obstruction group the success rate was only 50%, so that further modification to the technique and controlled studies are likely to be required before it could be recommended for general use.

Interventional radiology and the use of metal stents in nonvascular clinical practice: a systematic overview

PURPOSE

The intent of this systematic overview was to describe the clinical role of metal stents in nonvascular health care interventions and the level of evidence supporting their use.

MATERIALS AND METHODS

Structured searches of Medline were conducted and limited to original peer-reviewed articles published in English.

RESULTS

Clinical practice involving metal stents was reported in more than 109 clinical series involving 4,753 patients. Stents were placed mainly for palliation of malignant biliary, esophageal, and airway obstruction in patients who were untreatable or had surgically unresectable lesions. Assessment of these interventions has so far centered on safety and technical success. Efficacy, quality of life, and costing factors were not routinely reported. Randomized trial evidence was available but limited; six randomized trials involving metal stents have been reported. Three trials involved biliary malignant obstruction, and all three reported metal stent (132 patients) palliation to be superior to plastic stent palliation (136 patients) based on longer patency and lower reintervention costs. Safety and complication differences between stents, however, were inconsistent across trials. In three trials involving esophageal malignant obstruction, metal stent (82 patients) palliation was reported to be superior to plastic stent (41 patients), based on lower complication and reintervention rates, and superior to laser therapy (18 patients), based on better dysphagia relief.

CONCLUSION

Use of metal stents has been reported for obstructed ducts and passageways of most body systems. There is, however, limited controlled trial evidence confirming the advantages of their use over plastic stents or other forms of treatment.

Nasolacrimal polyurethane stent: complications with CT correlation

PURPOSE

To evaluate initial results in patients with epiphora secondary to obstruction of the nasolacrimal duct treated by placement of a polyurethane stent, and to discuss the technical problems and complications arising during the procedure, with visualization of the anatomy of the drainage apparatus using computed tomography (CT).

METHODS

We inserted 20 polyurethane Song stents under fluoroscopic guidance after dacryocystography in 19 patients with grade 3-4 epiphora caused by idiopathic obstruction of the nasolacrimal duct. CT scans were obtained following stent placement in all patients.

RESULTS

We focus on the technical problems and complications that arose during these procedures. During negotiation of the guidewire past the obstruction at the level of the junction of the duct with the lacrimal sac, the guidewire created a false passage in a posterior suborbital direction in two cases and towards the posterior midline in another. In all cases the guidewire was withdrawn and reinserted through the proper anatomic route without further difficulty or complications. In two cases the stent was improperly positioned wholly or partially outside the nasolacrimal system (one medially, one posteriorly). In one case the stent was removed and reinserted; in the other it remains in place and functional. CT was performed in all these cases to ensure proper anatomic alignment and determine what had gone wrong. The epiphora was completely resolved in 13 cases and partially relieved in four; there were three cases of stent obstruction. Epistaxis of short duration (1 hr) occurred in seven patients and headache in one.

CONCLUSIONS

Treatment of epiphora with polyurethane stents is a technique that is well tolerated by patients and achieves a high success rate, yet problems in placement may be encountered. Though no major consequences for patients are involved, cognizance of such difficulties is important to avoid incorrect positioning of stents.

CT-anatomy of the nasolacrimal sac and duct

Recent developments in ophthalmology such as balloon dilatation, stent implantation, laser therapy and endoscopy of the lacrimal drainage system raise the need for a detailed anatomical knowledge of this system. In this study morphometric measurements of the lacrimal drainage system were performed with thin-section axial computed tomography (CT) examinations in 147 patients with no signs of pathology related to the lacrimal drainage system. The mean length of the nasolacrimal duct measured 11.2 +/- 2.6 mm (range: 6-21 mm), the narrowest diameter was 3.7 +/- 0.7 mm (range: 2-7 mm). The mean length of the nasolacrimal sac was 11.8 +/- 2.5 mm (range: 6-18 mm). The width of the nasolacrimal sac did not exceed 4 mm unless filled with air. In 43 (29.3%) of the subjects air was visible within the nasolacrimal sac or duct. The knowledge of the morphometry of the lacrimal drainage system enables the ophthalmologist to plan intervention on the lacrimal drainage system precisely and avoid unnecessary manipulations.

Naso-lacrimal duct balloon dilatation

During a 30 month period (June 1991 to December 1993) 22 stenosed naso-lacrimal ducts in 18 patients were treated by balloon dilatation. A technical success rate of 86% was achieved, and the clinical success rate was 68%, in terms of either completely relieving or greatly improving the patients' symptoms of epiphora. The mean follow-up was 17 months. No complications were encountered.

The treatment of epiphora with balloon dacryocystoplasty

We examine a new treatment for epiphora: balloon dilatation of the nasolacrimal duct, or dacryocystoplasty. The procedure, which was performed as an out-patient procedure under local anaesthetic, was carried out on 20 patients with epiphora, 17 due to anatomical and 3 due to functional obstruction. There was an overall success rate of 60%, with complete relief of symptoms in 4 patients and a symptomatic improvement in another 8 (follow-up 2-9 months, mean 4.2 months). All patients tolerated the procedure well with minimal per-operative and post-operative discomfort. A higher success rate was seen in those patients with either a low anatomical or a functional obstruction. The procedure can be easily repeated and, if unsuccessful, still allows a dacryocystorhinostomy to be performed at a later date.