| ◄▬ | Miragel artikelen - 1997 Hwang ea | ▬► |
Hwang ea, 'Hydrogel Exoplant Fragmentation 10 Years After Scleral Buckling Surgery', (Arch Ophthalmol Vol 115. Sep 1997 1205)
In 1997 is het eerste geval van de lange termijn complicaties van de MlRAgel plombe in de medische literatuur gepubliceerd.
Hwang ea beschrijven in hun artikel van september 1997. de ontwikkelingsgang van de MAI plombe en de MlRAgel plombe, de aanvankelijk positieve verwachtingen en de latere negatieve ontwikkelingen.
Materials used for scleral buckling procedures in detachment repair have evolved from absorbable issues, including autogenouss fascia lata and cadaveric sclera or dura mater, to nonabsorbable ynthctic agents such as polyethylene tubing, solid silicone rubber, silicone sponges, and hydrogels. Hydrogels are hydrophilic materials formed from 3-dimensional polymer networks. The most widely sed hydrogel is co-poly(methylacrylate-2hydroxyethyl acrylate), or MIRAgel (MIRA, Waltham, Mass). The forerunner of MIRAgel, MAI, has the same chemical composition. HydrogeIs are permeable to water and low- molecular-weight hydrophilic substances. Their ability to absorb and then slowly release water-soluble antibiotics offers an advantage over silicone. Ho et al 1 reported that the MAI implant was as effective a buckling element as either solid silicone rubber or silicone sponge. He noted that the degree of swelling of the exoplant could be altered by varying its state of hydration, Îts softness and elasticity were protective against erosion, and it was less prone to infection because of its laek of dead spaees and its ability to absorb, then gradllally release antibiotics.
The apparent effeetiveness and safety of MAI hydrogel scleral exoplants was reported by Tolentino et al who followed up 82 eyes of 79 patients for 6 to 53 months and found no complications of buckle extrusion, erosion, or infection. However, with longer follow-up of 7 to 11 years, 7 complications of MAI exoplants were documented by Marin and colleagues. Clînical manifestations ranged from benign subconjunctival buIging to intraocular erosion aud migration of the exoplant. At the time of surgery, the exoplants were seen to be translucent, gel-like, and friabie. Erosion into thc vitreous cavity occurred in 1 case and was complicated by difficulty grasping the friable buckle material. Micro-Fourier transform infrared spectroscopic analysis of 2 recovered implants demonstrated hydrolytic degradation of the implant leading to swelling significantly greater than the original polymer. We report the first case, to our knowledge, of scleral buckle extrusion and fragmentation associated with a MIRAgel episcleral cxoplant.
Dit geval van complicaties als gevolg van de MlRAgel plombe kon volgens de auteurs geen verrassing opleveren gezien de eerder gerapporteerde 7 gevallen van MAl -complicaties.
This case represents the first reported breakdown of a MIRAgel sderal buckle. lts occurrenee should not be surprising,as cases of complications with the MAI exoplant,composed of the same hydrogel material, have been reported in the past. The mechanism of fragmentation and degradation likely resembles that reported with the MAI exoplant; hydrolysis of the material with resultant swelling. The presence of an incomplete capsule surrounding the buckle in our patient may have facilitated access of orbital fluid to the exoplant. Similar to the report by Marin et al,3 these changes appeared approximately 10 years after exoplant placement.
Hwang ea benadrukken de noodzaak om te anticiperen op mogelijke verbrokkeling en zwelling van de plombe.
The findings in this patient illustrate the need to anticipate potential friability and swelling of MIRAgel buckle material and to meticulously scarch for fragments during removal of long-standing exoplants.
Zij zien geen werkelijke voordelen van toepassing van de MAI en MIRAgel plombes in vergelijking met silicone plombes.
Our observation together with the historical data suggest that there are no real advantages of MIRAgeI and MAl over silicone for use as scleral buckling materiaL
Noten
1. Ho pc, Chan IM. Refojo MF, Tolentino FI, The MAl hydrophilic implant for scleral buckling: a
review. Ophthalmic Surg. 1984;15 :5 11 -515.
2. Tolentino FI, Roldan M, Nassifj , Refojo MI . Hydrogel implant for scleral buckling: long-term observalions. Retina. 1985;5:38-41.
3. Marin JF, Tolentino Fl, Refojo MF, Schepens CL, Long-term complications of the MAl hydrogel
buckling Implant. Arch Ophthalmol 1992; l lO :86-88
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| ◄▬ | 1997 Hwang ea | ▬► |