| ◄▬ | 2003 Le Rouic ea | ▬► |
Le Rouic ea, Late swelling and removal of rniragel buckles: a comparison with silicone indentations. Retina 2003;23:641-6
In een publicatie in 2003 beschrijven Le Rouic e.a. de verschillen tussen silicone en MIRAgel implants op basis van een retrospective analyse van de dossiers van 90 patiënten, bij wie tussen januari 1996 en december 1999 in hetzelfde ziekenhuis episcleraal toegepaste plombes zijn verwijderd.
Abstract
Background: To describe the indications for removal of Miragel episcleral buckles and to compare them with removed silicone sponges and solid silicone indentations.
Methods: Retrospective analysis of the charts of patients successfully treated for retinal detachment in whom the episcleral buckle was removed aftel' surgery, with a minimal follow-up of 6 months.
Results: In a series of 90 eyes of 90 patients, including 38 cases of Miragel elements, 25 cases of solid silicone, and 27 cases of silicone sponge remaval, the duration of indentation before removal was significantly langer with Miragel (91.9 months) than with solid silicone (10.6 months) and silicone sponges (18.6 months). In eyes treated with Miragel elements, swelling of the material with progressive limitation of ocular motility and protrusion of the buckle beneath the eyelids indicated its removal in 34 (89.5%) eyes. Infection of the buckle and erosion of the conjunctiva with an exposed indentation were significantly more common with silicone buckles. Overall, scleral perforation occurred in four (4.4%) eyes, and retinal redetachment occurred in eight (8.8%) eyes.
Conclusion: Late swelling of Miragel buckling elements represents a common indication for buckle removal, significantly different from silicone indentations.
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Episcleral buckling is a common technique used for retinaI detachment (RD) surgery. In some cases, however, the implant must be removed. 1-15 The two most common reasons for removal are extrusion, associated with or without buckle infection, 1-8,10, 13 and diplopia. 9, 10, 16-19 These complications have mostly been reported for eyes implanted with silicone sponges or solid silicone. Miragel elements have also been widely used for episcleral indentation. Initial series have reported a good tolerance of this material.20-21 With a longer follow-up, sporadic cases of late swelling of this material, which appeared fragmented during its surgical removal have been report ed. 11.14.15.22-28 Although the use of Miragel buckling elements has been discontinued, their explantation is subject of concern because of theu now established long-term complications. We also had to remove a large number of episcleral Miragel buckles. In this series, we describe the indications for their removal and compare them with the silicone buckles removed during the same period.
Methods
We reviewed the charts of patients who underwent episcleral buckling removal between January 1996 and December 1999 in a single institution. We selected the charts of patients treated with an episcleral Miragel buckling element, solid silicone, or silicone sponge indentation for a primary rhegmatogenous RD, a complete retinal attachment at the time of scleral buckle (SB) removal, and a follow-up of at least 6 months after explantation. (…)
Van alle verwijderde implants was 42% Miragel. Progressieve zwelling was in bijna 90% van de gevallen de reden voor verwijdering van de Miragel. Extrusie was de voornaamste reden voor verwijdering van silicone implants.
Discussion
Although we discontinued using Miragel buckles elements in 1995, they were still largely removcd between 1996 and 1999, representing 42% of all the buckles removed in this series. Progressive swelling of the material was the reason for removal in nearly 90% of cases. Eyes with removed Miragel buckles had significantly different characteristics than eyes with episcIcral silicone implants. Removal of silicone episcleral implants was often performed early after its placement, with 58% of the removed silicone buckles placed for 1 year or less. These results are concordant with previous series, in which 48% to 96% of episcleral implant removals were performed within the first year of RD surgery.4.5,7.10 Conversely, Miragel elerncnts were implanted for a significantly longer time before removal, except for one case removed less than 1 year after RD repair. However, we could not detect the early cases of Miragel buekle removal because the period of collection of the data started in January 1996 and we discontinued using this material in March 1995.
Extrusion of the buckle, with or without infection, was the main indication for removal of silicone implants, which is also concordant with previous studies. I.7.l0 In most of these cases, it was difficult to determine the mechanism leading to extrusion: primary infection, mechanical irritation of the surrounding tissue, or inadequate suture of the implant contributing to tissue loss and subsequent infection. Among the removed silicone implants, we observed a bacterial growth in 40% of cases, whereas only one Miragel implant had a positive culture. This difference was statistically significant.
Zoals ook al in eerdere studies is gemeld, zwelt en frgamenteert Miragel, hetgeen ook de auteurs hebbenondervonden bij de verwijdering van de implants. Het gefragmenteerde materiaal was moeilijk te verwijderen.
Miragel buckles were largely used in the 1980s and early 1990s. It was initially suggested that this material was well tolerated and less prone to infection because of its microporous surface, and it was also thought, at that time, to be a better buckling element.20 .21 After 7 to 13 years of follow-up, sporadic cases of intrascleral and episcleral Miragel removal as a result of the late swelling of the material have been reported leading to a restriction of ocular movements causing diplopia and progressive protrusion of the implant beneath the eyelids, which could mimic an orbital tumor.11.14.25-28 In these cases, fragmentation of the buckling material was observed, rendering the removal technically difficuit. We also met difficulties in grasping this fragmented material. Cryoextraction of the buckle seemed to be the best technique for explantation.28 The swelling and fragmentation of this material seems to be the consequence of a peripheral degradation of the implant associated with a foreign body giant cell granuloma.22-24 To our knowledge, only one series of 13 eyes has addressed the characteristics and the outcome of patients needing episcleral Miragel buckle elements removal.25 In our series, Miragel elements were implanted for a longer time than episcleral silicone sponges or solid silieone implants and had a significantly lower rate of extrusion, exposition of the indentation, and bacteriologically proven buckle infection. With a maximal follow-up of 10 years, the mean time from RD surgery to removal was approximately 8 years, which is similar to the duration observed by Gribomont. 25 Although we were notable to assess the rate of removal of Miragel elements after a definite duration or implantation because or variable follow-up patterns, our results seem to be different from those of the series by Roldan-Pallares et al,15 whieh reported a 2.4% rate of Miragel implants removal, with a follow-up of 7 years or mores.
De auteurs doen ook de aanbeveling om patiënten voortdurend te volgen en te informeren over de mogelijke complicaties. Zij pleiten er niet voor dat door patiënten goed verdragen implants worden verwijderd vanwege de risico’s van netvliesloslating sclera beschadiging. Anderzijds moet verwijdering van de Miragel-plombe worden overwogen bij de eerste tekenen van zwelling om de grote fragmentatie van de implant te voorkomen, die verwijdering technisch bemoeilijkt en zelfs gevaarlijk is voor de onderliggende sclera.
After reviewing all these late complications, we think that patients implanted with Miragel buckles intrasclerally or episclerally should undergo a close and long-lasting follow-up, ideally by their eye surgeon, be informed of the potential long-term complications of Miragel elements, which were not known at the time of their RD repair, and be asked to present promptly if they notice ocular motility disturbance or a bulkiness of their indentation. Although it is possible that, after 10 years or more in the eye, Miragel implants invariably swell up, we do not advocate for a systematic removal of well-tolerated buckles, because retinal redetachment and scleral rupture are still potential visualthreatening complications of indentation removal. Conversely, the SB extraction should be considered as soon as the first signs of Miragel swelling occur to avoid a major fragmentation of the buckle, which renders the removal technically difficult or even dangerous to the underlying sclera.
Although the use of Miragel buckling elements is now discontinued, this type of material is still a subject of concern because of the long-term swelling that will often lead to removal of the buckle. In this series, the mean time from surgery to Miragel buckle elements removal was approximately 8 years. However, our longest follow-up does not exceed 10 years. This example of a late complication of an initially welltolerated material is an invitation to increase our vigilance when following up patients with any type of implant.
| ◄▬ | 2003 Le Rouic ea | ▬► |