| ◄▬ | 2004 Kearney ea | ▬► |
Keamey ea, Complications ofhydrogel explants used in scleral buckling surgery, Am J Ophthalmol 2004;137:96-100
Kearney e.a. beschrijven in een artikel van januari 2004 een groep van 15 patiënten (17 ogen) met "symptoms of pain, strabismus, sensation of orbital fullness and presence of a subconjuntival mass many years after successful scleral buckling surgery using hydrogel explants". Zij hadden de evaring dat verwijdering moeilijk was omdat het hydrogel materiaal bros was en fragmenteerde en zij concluderen dat vroegtijdige herkenning ernstige complicaties van uitgestelde verwijdering kan voorkomen:
Abstract
PURPOSE: To report a group of patients with symptoms of pain, strabismus, sensation of orbital fullness, and presence of a subconjunctival mass many years after successful scleral buckIing surgery using hydrogel explants.
DESIGN: We present an interventional consecutive case series of patients who underwent scleral buckIing surgery using hydrogel explants from 4 to 14 years before onset of clinical symptoms.
SETTING: This is a retrospective, multicenter clinical study. Patient population: 17 eyes of 15 patients presented with this disorder. All patients were examined; Snellen acuity, ocular motility, tonometry, sIit lamp, and fundus examination were recorded. Two patients underwent either computed tomography or magnetic resonance imaging. Removal of the hydrogel explant was attempted in all patients. Removal of the buckle was technically difficuit; the hydrogel material was fragiIe and fragmented when handled.
RESULTS: All patients had prompt relief of pain and discomfort. Ocular motility and diplopia were greatly improved. Extraocular muscIe surgery was not required in any case. Three eyes had intraoperative eye wall perforation. One eye developed postoperative bacterial endophthalmitis. Five eyes had recurrence of retinaI detachment. One eye had additional complications of corneal edema and glaucoma.
CONCLUSIONS: Patients who develop this clinical condition should be considered for removal of the hydrogel scleral buckle. Early recognition of this condition may prevent serious complications associated with delayed removal.
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In 1979 the hydrogel implant, copoly/methyl/acrylate-2-hydroxyethyl acrylate (Miragel, Medical Instruments Research Associates, Waltham, Massachusetts, USA), a soft, pliable material that could withstand tension of sutures (except nylon), was introduced as a new scleral buckling material in the surgical management of retinal detachment.1 It was meant to be hydrated by tissue fluids, allowing it to enlarge postoperatively and increase buckle height. The original intent in its use was to supplement an intrascleral solid silicone element, but it was soon found suitable as an explant and as a principal buckling element (Figure 1). Early reports showed that the material was well tolerated and produced the desired effect with few complications.2
In 1992 a report by Marin and associates of complications 7 to 11 years after scleral buckling with a similar hydrogel element suggested that a clinical disorder resulting from continued swelling of this material might soon become a problem.3 Recently, this disorder, related to continued swelling and subconjunctival protrusion of the scleral buckling element, was recognized.4,5
In this report we present a series of 17 eyes of 15 patients that developed this disorder between 4 and 14 years after scleral buckling surgery. These patients presented with some or all of the following symptoms and findings: ocular pain and discomfort, poor lid-globe apposition with exposure keratopathy, oculomotor restriction with progressively worsening diplopia, the sensation of eye "bulging," and the presence of a visible or palpable mass beneath the conjunctiva or eyelid (Figures 2, 3).
De auteurs geven een mogelijke verklaring voor het zwellingsproces:
We propose the following mechanism for hydrogel buckle expansion, based on recent literature and parallels to experience with other forms of scleral bllckling materiaIs. Prolonged exposure of the hydrogel material to tissue fluids resulted in a change in its chemical and physical makeup.3 The altered explant then became hydrated and swollen to the degree that sutures holding the ends of the buckle cut through the hydrogel, producing a prominent mass. The sutures anchoring the explant were placed under tension and pulled through the sclera, exposing the choroid where sutures had been placed deeply. Those sutures that did not pull through the sclera maintained pressure of the explant on the sclera, thinning it to the point that areas of choroid were exposed. The continued expansion of the explant resulted in its occupation of most of the anterior orbit. This mass effect, plus inflammation and fibrosis of the orbital tissues, resulted in the restrictive myopathy observed.7 The absence of a nonyielding encircling silicone band further allowed for continlled enlargement of the explant.
Zij waarschuwen er ook voor dat de aard van de hydrogel plombe vaak onbekend is, omdat de fabrikant omstreeks 1994 ermee gestopt is, en de arts de oorzaak van het probleem vaak niet onderkent.
Hydrogel buckling material is no longer available. It was discontinued by the manufacturer in approximately 1994 (oral communication, Medical Instruments Research Associates). There is, however, a large group of patients who have had this material implanted and might be expected to develop the clinical picture described here.
Patients who have undergone scleral buckling with hydrogel before 1995 are at risk of developing this disorder. Often the nature of the buckling element is unknown and the physician does not consider the possibility of a relation between the scleral buckling surgery and the symptoms of diplopia, pain, and orbital mass. Physicians need to be made more aware of this condition and should consider its possibility in a patient who presents with peculiar orbital and motility problems and has undergone retinal surgery in the past.
De auteurs kunnen niet exact aangeven wanneer de verwijdering geïndiceerd is.
We do not have sufficient experience to determine exact indications for removal of these hydrogel buckling elements or the timing of their removal. In our cases, the decision was not difficult; the patients were very symptomatic and readily agreed to surgical removal. As more experience is gained, we wi1l be able to make this decision in the patient with milder symptoms.
Zij signaleren dat de verwijdering van de plombe moeilijk is:
Removal of the buckle is difficult. A single small incision used for silicone buckle removal was found insufficient. A 360-degree conjunctival opening may be preferred. The buckle cannot be grasped easily with instruments. Rather than grasping and pulling on the element, we suggest cutting it in each quadrant and pushing it through the fibrous tunnel to an open quadrant. Because of this difficulty and our incidence of eye wal! perforation, we do not believe this is an office procedure. We also recommend against extensive exploration of the sclera and aggressive attempts to remove all traces of the hydrogel material.
Een derde van de gevallen leidde tot nieuwe netvliesdefecten:
The incidence of redetachment of the retina after hydrogel buckle removal was high (nearly one third of our cases).
| ◄▬ | 2004 Kearney ea | ▬► |