ABSTRACT
Objetivo: Las quemaduras oculares químicas con compromiso extenso de limbo (mayor del 50%) tienen mal pronóstico visual con manejo médico como única alternativa terapéutica; por lo que el propósito de este trabajo es evaluar el tratamiento temprano con el implante de membrana amniótica en cuanto a resultados anatómicos y funcionales en estos pacientes. Metodología: Estudio retrospectivo tipo serie de casos. Se presentan los resultados visuales en 9 ojos de 6 pacientes tratados en la Clínica de Oftalmología de Cali y el Hospital Universitario del Valle con quemadura ocular química grave a los que se les realizó implante precoz de membrana amniótica adjunto al manejo oftalmológico convencional. Resultados: Todos los pacientes tuvieron mejoría de la agudeza visual. El 87% de ellos lograron una agudeza visual mejor corregida (AVMC) de 20/30 o mejor. Ningún paciente desarrolló simbléfaron ni requirió trasplante heterólogo de córnea. Conclusiones: Los resultados presentados sugieren que el implante de membrana amniótica precoz adicional a la terapia médica, puede ser el manejo de elección en la fase aguda de quemaduras químicas extensas de superficie ocular (compromiso mayor del 50% de limbo), ya que mejora el pronóstico visual con respecto a la terapia médica como único manejo.
Purpose: Ocular chemical burns with extensive limbus involvement (greater than 50%) have poor visual prognosis with medical management as the only therapeutic alternative; So the purpose of this work is to evaluate if early treatment with amniotic membrane implant improves the anatomical and functional results in these patients. Methods: Retrospective study of a cases series. We present the visual results in 9 eyes of 6 patients treated at the Cali Ophthalmology Clinic and the Valle´s University Hospital with severe chemical ocular burns who underwent early amniotic membrane implantation added to conventional ophthalmologic management. Results: All patients had improvement of visual acuity. 87% of patients achieved a better corrected visual acuity (BCVA) of 20/30 or better. No patient developed simblefaron or required heterologous corneal transplantation. Conclusions: The results presented suggest that amniotic membrane implantation in addition to medical therapy could be the management of choice in the acute phase of extensive ocular surface chemical burns (involvement greater than 50% of limbo), since it improves the visual prognosis with respect to medical therapy as sole management.
Subject(s)
Humans , Ophthalmologic Surgical Procedures , Amnion , Eye Burns , Limbus CorneaeABSTRACT
Recently, various tube-shunt implants have been used in treating refractory glaucomas.They have large volumed reservoir portion made of hard materials.We made a new implant with soft and freely malleable membrane[expanded polytetrafluoroethylene, e-PTFE]as a reservoir portion attached to the conventional silicone tube. Based on the encouraging result from experimental animal study, we performed a clinical trial for the membrane-tube implant.We performed Glaucoma Tube-Shunt Implant surgery using double layers of e-PTFE membrane and silicone tube with its one end fixed between the two layers.The subjects had refractory glaucomas without useful vision who visited our hospital from May 1991 to Sep.1995. There were 40 eyes of 37 patients and their mean follow-up period was 32.6 months.We could control the IOP within 6~21 mms of mercury in 26 eyes[65.0%, Success].In remaining 14 eyes, we could not control the IOP or additional surgery was needed to control the IOP or treat severe complications[35.0%, Failure].The Kaplan-Meier Survival for IOP control was 78.4% at 1 yr, 71.6%at 2 yr, and 60.3%at 3 yr.The complications were similar to those of other commercially available Glaucoma implants. This new implant is made of soft, freely malleable membrane for the reservoir portion with small volume which can be inserted with smaller incision on the conjunctiva with less complication.We have obtained comparable result from this membrane-tube implant to other implants, and it may be considered as an another substitute for the treatment of refractory glaucomas.
Subject(s)
Animals , Humans , Conjunctiva , Follow-Up Studies , Glaucoma , Membranes , Polytetrafluoroethylene , SiliconesABSTRACT
This experiment used 30 rabbits (40 normal eyes) to determine the applicability of an expanded polytetrafluoroethylene (e-PTFE) surgical membrane as a glaucoma seton. The e-PTFE membrane had 0.1 mm thickness and was cut into T-shaped pieces measuring about 2x7 mm. One end of the implant was introduced into the anterior chamber through a sclerectomy opening and the other ends were allowed to extend from the Iamellar scleral flap into the subconjunctival space. During the follew-up at the end of 8 weeks, all the eyes with an implant showed an apparent filtering bleb, while only one of 6 eyes that had undergone a trabeculectomy alone did. The location of the created filtering blebs depended on the implant position. Pestoperative inflammatory changes were unremarkable. Histologic examinations reyealed a tissue-free cystic space surrounding the e-PTFE implants which maintained their original color, thickness, pliability and size. Transmission electron microscopy showed few myofibroblast-like cells in the fibrous wall containing the implant. With scanning electron microscopy, the internal end of the implant strip had a clean surface and no adhesions to adjacent structures of the anterior chamber angle. The corneal endothelial cells were intact in the area close to the tip of the implant. Considering the clinical and histologic findings, it appeared that the e-PTFE was acceptably innocuous in the anterior segment of the eye and a convenient material as a glaucoma seton.