Nuzzi & Rossi -Buckle removal in retinal detachment surgery, Acta Biomed 2008,79: 128-132 

De auteurs evalueren de uitkomsten van verwijdering van silicone respectievelijk Miragel plombes bij 46 patiënten, die eerder een netvliesscheur-operatie hadden ondergaan. Verwijdering geschiedde vanwege klachten in verband met extrusie van de plombe, voortdurende conjunctivitis, dubbelzien en vermindering van de gezichtscherpte. Noch postoperatieve complicaties noch recidieve netvliesloslatingen deden zich voor. Adequaat toegepaste retinopexie *) tijdens de primaire chirurgie voorkomt waarschijnlijk het opnieuw optreden van retinale loslating.

*) netvliesoperaties bij netvliesloslating  (Oogfonds): 
- cerclage/plombe (uitwending)
- vitrectomie
- pneumatische retinopexie

Abstract
Purpose: To evaluate the outcome after buckle removal in a consecutive series of treated detachments.
Methods: Segmental and/or encircling buckles were removed in 46 consecutive patients operated upon for rhegmatogenous retinal detachment, showing buckle extrusion, recurrent pain, and diplopia. Patients underwent a preoperative retinal examination, and a six- months postoperative follow-up.
Results: Cryopexy of retinal breaks was performed in all 46 patients during the primary surgery. At the time of buckle removal none of the patients underwent argon-laser treatment. The removed buckling material was made of MIRAGEL® in 32 cases (74%), silicone sponge in 7 (17%), and silicone band in 4 (9%). The time between the first surgery and buckle removal ranged from 1 to 17 years (8±7.5, M±SD). Neither postoperative complications, nor recurrences of retinal detachment developed. Best corrected visual acuity remained unchanged during the follow-up. Diplopia resolved in all 4 eyes after buckle removal with no need for a strabismus operation, prismatic lenses were required in one case only.
Conclusions: Although the absence of a control group, the adequately applied retinopexy during primary surgery could probably prevent the recurrence of retinal detachment. (www.actabiomedica.it)

Introduction
The extrusion and infection of materials used for segmental and encircling buckling occurs in 1% of cases (1, 2). This risk increases when more than one element is used, and when the same eye undergoes multiple surgeries (1, 2). In the majority of cases, a buckle removal is sufficient to resolve the clinical situation, with a low risk of recurrence of retinal detachment (between 4% and 33%) (3).

Materials and methods
In our study, the consecutive series of patients who had undergone a scleral buckling operation for rhegmatogenous retinal detachment, were examined before and after surgery by which the indentation material was removed between 2000 and 2005. The study was performed in accordance to the Declaration of Helsinki’s principles, and all the persons gave their informed consent prior to their inclusion in the study.
Fourty-six eyes of 46 patients, had undergone surgery for rhegmatogenous retinal detachment between 1985 and 2001 and the buckle material was removed between September 2000 and November 2005, with a mean time from first surgery of 8±7.5 years (M±SD). In all cases, the same surgeon (G.N.) had performed the first and second operation.
The patients were examined prior to surgery and at one and six months during follow-up.
The clinical symptoms that led to buckle removal appeared after various intervals of time, ranging from 1 to 17 years after the primary surgery. (…)

Results (…)
In our study no intraoperative nor postoperative complications occurred, and no patient developed a recurrence of retinal detachment during the followup. (..)

Discussion
Buckle extrusion, MIRAGEL® in particular, is widely reported in literature. In one publication the mean latency reported ranged at 8.3 years, varying between 6 months and 14 years [6]. The high risk of extrusion of MIRAGEL® buckles has been correlated to the great tendency of the material to hydrate, combined with alterations of its microscopic structure (4), progressive increase of volume, subsequent fragmentation and loss of indentation effect.
Of the 43 patients in the study, 32 (74%) eyes had MIRAGEL® material, 7 (17%) had silicone sponge buckles and 4 (9%) silicone bands. In 8 eyes (19%), the segmental buckle and retinopexy were combined with an encircling band. Only one of these was removed, due to evidence of necrosis.
The findings which led to the indication of buckle removal are in agreement with what is described in the literature, that means eye discomfort or ocular pain, combined with extrusion of the buckle, persistent conjunctivitis, diplopia and decrease of visual acuity (5). Unlike other studies, we did not observe any significant difference in the symptoms in relation to the buckle materials applied (6). Diplopia resolved in all eyes after buckle removal, with no need for subsequent strabismus operation. Only one eye required prisms for correction.
The time elapsing between buckle implanting and its removal varied from 1 to 17 years in our study, with the longest latency for the silicon bands, and the shortest for silicone sponge. Past studies confirm the shorter duration of silicone sponge, but identified MIRAGEL® as the material with the longest lasting indentation (6, 7). Except for one eye, it was not necessary to remove the encircling buckle combined with the scleral buckle, when present, because it was well tolerated and there were no signs of scleral erosion.
In our study, none of the patients underwent laser “prophylactic” treatment prior to buckle removal and no redetachment was observed. The operative notes show that in all eyes intraoperative cryopexy was routinely performed at the primary surgery. It’s not possible, anyway, to determine whether, in the absence of this treatment, recurrences would have occurred. In our opinion retinopexy at the time of the primary surgery (intraoperative cryopexy) exactly placed around the break and of correct dosage could safeguard from recurrence of a retinal detachment, if it should necessary to remove the buckle material. The Retinopexy scars provide a sufficient protection against vitreo-retinal tractions on the break when the buckling effect starts to decrease. This is also the case of MIRAGEL® buckles, that hydrolyse after a few years with a resulting decrease of the indentation effect (4).

A well performed cryopexy, i.e. under ophthalmoscopic control and with minimal whitening of the retina, would not increase the risk of postoperative vitreous proliferation (8), and provides an excellent protection against redetachment. At our knowledge, it has not yet been demonstrated that indentation alone can induce a retinopexic scar comparable to that caused by cryopexy or laser treatment. Moreover, at our knowledge, the literature does not indicate a safe time for buckle removal in retinal detachment surgery. The procedure appeared to be a somehow not risky for the eye, combined with a great chance that the symptoms will be resolved.