The migration of an encircling band through the extraocular muscles is an extremely rare complication of retinal detachment surgery, which may give rise to ocular motility disturbances and trophic changes at the cornea–scleral junction. This report describes the cheese wiring of a 240 silicone encircling band through the superior and the lateral rectus muscles of a highly myopic eye over a period of seven years. Removal of the exoplant in local anesthaesia alleviated the visual symptoms with no surgical complications.

Case report

A 44-year-old gentleman was admitted with an inferior rhegmatogenous retinal detachment in his left myopic eye (−10 D). A silicone 240 band (Labtician, Oakville, Ontario, Canada) was placed under the four rectus muscles and fixed with a braided non-resorbable suture in all four quadrants. In addition, cryocoagulation, external drainage, and injection of 0.5 ml of air through the pars plana was performed. At 5 months after successful reattachment, the patient presented with a new retinal break and detachment at 7 o'clock anterior to the encircling band. The 240 silicone band was replaced anteriorly and cryocoagulation of the new retinal break was applied. During the next 4 months, the retina remained attached, and the patient was lost to follow-up afterwards. After 7 years, he presented again with a foreign body sensation in his operated eye. This was associated with vertical diplopia, which the patient had noticed for about 1 year before seeking advice. Clinical examination showed a visual acuity of 1.0 OS and the 240 encircling band in the subconjunctival space at the level of the limbus (Figure 1a and b). Ophthalmoscopy showed a completely attached retina. Intermittent hypotropia of the left eye with vertical diplopia was revealed using the Hess–Weiss test. The encircling band was surgically removed in local anaesthesia without incident and no local irritation was present 1 month postoperatively (Figure 2). A postoperative Hess–Weiss test showed a reduction in left hypertropia with possible fusion. Clinical follow-up for more than 1 year has shown no recurrence of diplopia.

Figure 1
figure 1

(a and b) 240 Silicone encircling band well visible in the subconjunctival space (arrows) of the left eye at the nasal (top) and superior limbus (bottom).

Figure 2
figure 2

The bed of the encircling band (arrow) can still be seen 2 months postoperatively with a thinned sclera. Note that no local irritation is present anymore.


Although the pathophysiological mechanism remains unknown, it has been suggested that the encircling band may ‘cheese wire’ forward through the superior and internal rectus insertions.1, 2, 3 It has been hypothesised that the extraocular muscles form adhesions with the implanted material, and may thus remain firmly attached to the globe despite erosion of the buckle through the muscle insertions. It has been suggested that risk factors for migration of the silicone band include a placement of the band anterior to the equator, too much tightening of the band, or an insufficiently anchored band to the sclera.3 In high myopia, extensive intraoperative cryocoagulation may alter tissue configurations with consecutive band migration.4, 5 An alternative explanation for the migration may be that the silicone band had been mistakenly placed over the muscle insertion instead of underneath the muscle. However, this seems very unlikely in our case given the expertise of the surgeon. Contrary to our case, the migrating encircling band is not usually linked to ocular motility disturbance.1, 2 Patients retain a full range of ocular movements and usually normal binocular fusion, indicating that the muscle tendon was not recessed from its insertion and that the scar tissue did not limit its action. The clinical prognosis after replacement or removal of the irritating silicone band is excellent.