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Re: Nasolacrimal Stents in the Treatment of Epiphora: Long-term Results
Letters to the Editor
Re: Nasolacrimal Stents in the Treatment of Epiphora: Long-term Results From: Carlos Lanciego, MD Lorenzo García García, MD Interventional Radiology Unit Hospital “Virgen de la Salud” Complejo Hospitalario de Toledo Avda. de Barber s/n 45005 Toledo, Spain Editor: We read with great interest the recently published paper by Paúl et al (1) dealing with nasolacrimal stent placement and its long-term results in the management of epiphora. The efficacy of the soft polyurethane stent designed by Song was assessed with a “long-term” follow-up of 2 years. The authors conclude that stent placement should not be recommended as a final treatment for epiphora. To our surprise, such a radical suggestion was based on the outcome from only 79 stents placed in 67 patients. The initial technical success was estimated at 88%, with a primary patency rate of only 40% (median of 27 months of follow-up). At the end of the study, 45 stents became occluded (obstruction rate as high as 60%), including 16 stents that were inadequately placed initially. Forty blocked stents were removed, although no data of secondary patency after removal were reported (eight cases undergoing repeat stent placement were mentioned). These data are clearly controversial when compared with the results published by Song et al (2) and Lanciego et al (3), the latter group having reported an initial technical success rate as high as 97%, an obstruction rate lower than 30%, and an estimated secondary patency rate of approximately 35% (28 months of follow-up). In addition, the feasibility of stent extraction is highlighted by a failure rate of only 3% (4). These obvious differences were recognized by Paúl et al (1), the low success rate being related to the lack of ophthalmologic care and the high rate of stent malpositioning. Despite this reasoning, the authors still conclude that stent placement should not be the choice for epiphora treatment. A second pivotal issue is the argument linking difficulties in extracting obstructed stents and presumed apparent further problems when undergoing dacryocystorhinostomy. This point has not been demonstrated by the scientific community to date, so the report by Paúl et al (1) is speculative in this matter. In our own experience, no additional problems in dacryocystorhinostomy performance after stent removal were noted by ophthalmologists in seven patients. Similar results were reported by Song et al (2) in the outcome of six patients undergoing dacryocystorhinostomy after stent removal. The presumptive negative influx (if it exists) of stent placement (and subsequent removal when required) and dacryocystorhinostomy is still a matter of debate. In accordance with the statements made by Paúl et al (1), we also believe that a multicentric, prospective, comparative, randomized, double-blind study will be clearly acknowledged by the scientific community at large. In the meantime, our belief is that it is obviously too early to stop the use of a technical tool characterized by its feasibility, which is well tolerated by patients, performed on an outpa-
854
tient basis, is not time-consuming, and which, at the moment, is considered to be the first step—in most cases a definitive treatment—in the overall management of epiphora. References 1. Pau´l L, Pinto I, Vicente JM, Armendariz A, Moreno G, Cruz Baraibar M. Nasolacrimal stents in the treatment of epiphora: long-term results. J Vasc Interv Radiol 2002; 13:83– 88. 2. Song HY, Lee DH, Ahn H, et al. Lacrimal system obstruction treated with lacrimal polyurethane stents: outcome of removal of occluded stents. Radiology 1998; 208:689 – 6942. 3. Lanciego C, De Miguel S, Perea M, et al. Nasolacrimal stents in the management of epiphora: medium-term results of a multicenter prospective study. J Vasc Interv Radiol 2001; 12:701–710. 4. Kim HS, Song HY, Kim TH, et al. Use of a lacrimal stent retrieval hook in the removal of occluded plastic and expandable metallic lacrimal stents. J Vasc Interv Radiol 2000; 11:762–766.
Drs. Paúl et al respond: In reply to the letter to the Editor sent by Lanciego et al concerning our paper “Nasolacrimal Stents in the Treatment of Epiphora: Long-term Results” (1), we would like to address certain points in need of further elucidation. To begin, the qualifier “clearly controversial” would not seem to be appropriate when used to refer to our results concerning the long-term occlusion rate of nasolacrimal stents (NLSs) as compared to the results reported for other published series, because the follow-up is, quite simply, not comparable. Follow-up as reported in our paper starts virtually at the point at which it leaves off in the papers that have been cited as conflicting. Lanciego et al (2) considered 183 stents over a mean follow-up time of 15 months (mean ⫽ 450 d, range ⫽ 8 –730 d), not 28 months as stated in their letter, with a blockage rate of 15%. Song et al (3) reported on 571 stents with a mean follow-up time of 7 months and an occlusion rate of 25%. Based on length of follow-up, the papers by Song et al (3) and Lanciego et al (2) are more comparable to an earlier paper by our group (4) concerning a series of 70 stents with a mean follow-up time of 11.2 months (range ⫽ 1–20 mo) and an occlusion rate of 33% than to our latest paper, which dealt with 79 stents over a mean follow-up period of 27 months (range ⫽ 16 –38 mo), with an occlusion rate of 60%. In any case, as was noted in our paper, for their respective follow-up times, the results reported by Lanciego et al (2), together with those reported by Lee et al (5) (59 nasolacrimal stents inserted without radiologic guidance, with an occlusion rate of 8% after a mean follow up of 22 mo), are the best results published in terms of occlusion rate and malpositioning rate (not mentioned, hence we have assumed it to be zero), as well as for secondary patency upon removal of blocked stents (89.5% at 15 mo). Larger series have had higher occlusion rates—31% after 1 year for 283 NLSs (6)—and lower secondary patency rates for the lacrimal system—51% at 7 days and 18% at 22 months (3). Moreover, in certain cases, we have encountered adverse effects of the implanted stents on the lacrimal system, namely adhesion affecting the stents in the long term. In such cases, removal of the stents under radiologic guidance
Re: Nasolacrimal Stents in the Treatment of Epiphora: Long-term Results From: Carlos Lanciego, MD Lorenzo García García, MD Interventional Radiology Unit Hospital “Virgen de la Salud” Complejo Hospitalario de Toledo Avda. de Barber s/n 45005 Toledo, Spain Editor: We read with great interest the recently published paper by Paúl et al (1) dealing with nasolacrimal stent placement and its long-term results in the management of epiphora. The efficacy of the soft polyurethane stent designed by Song was assessed with a “long-term” follow-up of 2 years. The authors conclude that stent placement should not be recommended as a final treatment for epiphora. To our surprise, such a radical suggestion was based on the outcome from only 79 stents placed in 67 patients. The initial technical success was estimated at 88%, with a primary patency rate of only 40% (median of 27 months of follow-up). At the end of the study, 45 stents became occluded (obstruction rate as high as 60%), including 16 stents that were inadequately placed initially. Forty blocked stents were removed, although no data of secondary patency after removal were reported (eight cases undergoing repeat stent placement were mentioned). These data are clearly controversial when compared with the results published by Song et al (2) and Lanciego et al (3), the latter group having reported an initial technical success rate as high as 97%, an obstruction rate lower than 30%, and an estimated secondary patency rate of approximately 35% (28 months of follow-up). In addition, the feasibility of stent extraction is highlighted by a failure rate of only 3% (4). These obvious differences were recognized by Paúl et al (1), the low success rate being related to the lack of ophthalmologic care and the high rate of stent malpositioning. Despite this reasoning, the authors still conclude that stent placement should not be the choice for epiphora treatment. A second pivotal issue is the argument linking difficulties in extracting obstructed stents and presumed apparent further problems when undergoing dacryocystorhinostomy. This point has not been demonstrated by the scientific community to date, so the report by Paúl et al (1) is speculative in this matter. In our own experience, no additional problems in dacryocystorhinostomy performance after stent removal were noted by ophthalmologists in seven patients. Similar results were reported by Song et al (2) in the outcome of six patients undergoing dacryocystorhinostomy after stent removal. The presumptive negative influx (if it exists) of stent placement (and subsequent removal when required) and dacryocystorhinostomy is still a matter of debate. In accordance with the statements made by Paúl et al (1), we also believe that a multicentric, prospective, comparative, randomized, double-blind study will be clearly acknowledged by the scientific community at large. In the meantime, our belief is that it is obviously too early to stop the use of a technical tool characterized by its feasibility, which is well tolerated by patients, performed on an outpa-
854
tient basis, is not time-consuming, and which, at the moment, is considered to be the first step—in most cases a definitive treatment—in the overall management of epiphora. References 1. Pau´l L, Pinto I, Vicente JM, Armendariz A, Moreno G, Cruz Baraibar M. Nasolacrimal stents in the treatment of epiphora: long-term results. J Vasc Interv Radiol 2002; 13:83– 88. 2. Song HY, Lee DH, Ahn H, et al. Lacrimal system obstruction treated with lacrimal polyurethane stents: outcome of removal of occluded stents. Radiology 1998; 208:689 – 6942. 3. Lanciego C, De Miguel S, Perea M, et al. Nasolacrimal stents in the management of epiphora: medium-term results of a multicenter prospective study. J Vasc Interv Radiol 2001; 12:701–710. 4. Kim HS, Song HY, Kim TH, et al. Use of a lacrimal stent retrieval hook in the removal of occluded plastic and expandable metallic lacrimal stents. J Vasc Interv Radiol 2000; 11:762–766.
Drs. Paúl et al respond: In reply to the letter to the Editor sent by Lanciego et al concerning our paper “Nasolacrimal Stents in the Treatment of Epiphora: Long-term Results” (1), we would like to address certain points in need of further elucidation. To begin, the qualifier “clearly controversial” would not seem to be appropriate when used to refer to our results concerning the long-term occlusion rate of nasolacrimal stents (NLSs) as compared to the results reported for other published series, because the follow-up is, quite simply, not comparable. Follow-up as reported in our paper starts virtually at the point at which it leaves off in the papers that have been cited as conflicting. Lanciego et al (2) considered 183 stents over a mean follow-up time of 15 months (mean ⫽ 450 d, range ⫽ 8 –730 d), not 28 months as stated in their letter, with a blockage rate of 15%. Song et al (3) reported on 571 stents with a mean follow-up time of 7 months and an occlusion rate of 25%. Based on length of follow-up, the papers by Song et al (3) and Lanciego et al (2) are more comparable to an earlier paper by our group (4) concerning a series of 70 stents with a mean follow-up time of 11.2 months (range ⫽ 1–20 mo) and an occlusion rate of 33% than to our latest paper, which dealt with 79 stents over a mean follow-up period of 27 months (range ⫽ 16 –38 mo), with an occlusion rate of 60%. In any case, as was noted in our paper, for their respective follow-up times, the results reported by Lanciego et al (2), together with those reported by Lee et al (5) (59 nasolacrimal stents inserted without radiologic guidance, with an occlusion rate of 8% after a mean follow up of 22 mo), are the best results published in terms of occlusion rate and malpositioning rate (not mentioned, hence we have assumed it to be zero), as well as for secondary patency upon removal of blocked stents (89.5% at 15 mo). Larger series have had higher occlusion rates—31% after 1 year for 283 NLSs (6)—and lower secondary patency rates for the lacrimal system—51% at 7 days and 18% at 22 months (3). Moreover, in certain cases, we have encountered adverse effects of the implanted stents on the lacrimal system, namely adhesion affecting the stents in the long term. In such cases, removal of the stents under radiologic guidance