Comparison of 20% sulfur hexafluoride with air for intraocular tamponade in Descemet membrane endothelial keratoplasty (DMEK) / Comparação de hexafluoreto de enxofre a 20% com ar para tamponamento intraocular na ceratoplastia endotelial de membrana Descemet (DMEK)

ABSTRACT Purpose: To compare the effect of 20% sulfur hexafluoride (SF6) with that of air on graft detachment rates for intraocular tamponade in Descemet membrane endothelial keratoplasty (DMEK). Methods: Forty-two eyes of patients who underwent DMEK by a single surgeon (A.S.J.) at Wilmer Eye Institute between January 2012 and 2014 were identified; 21 received air for intraocular tamponade and the next consecutive 21 received SF6. The main outcome measure was the graft detachment rate; univariate and multivariate analyses were performed. Results: The graft detachment rate was 67% in the air group and 19% in the SF6 group (p<0.05). No complete graft detachments occurred, and all partial detachments underwent intervention with injection of intraocular air. The percentages of eyes with 20/25 or better vision were not different between the groups (67% vs. 71%). Univariate analysis showed significantly higher detachment rates with air tamponade (OR, 8.50; p<0.005) and larger donor graft size (OR, 14.96; p<0.05). Multivariate analysis with gas but not graft size included showed that gas was an independent statistically significant predictor of outcome (OR, 6.65; p<0.05). When graft size was included as a covariate, gas was no longer a statistically significant predictor of detachment but maintained OR of 7.81 (p=0.063) similar to the results of univariate and multivariate analyses without graft size. Conclusion: In comparison with air, graft detachment rates for intraocular tamponade in DMEK were significantly reduced by 20% SF6.

RESUMO Objetivo: Comparar as taxas de descolamento do botão endotelial com o uso de gás hexafluoreto de enxofre a 20% (SF6) em relação ao ar para o tamponamento intraocular na ceratoplastia endotelial da membrana de Descemet (DMEK). Métodos: Quarenta e dois olhos foram operados com a técnica de DMEK por um único cirurgião (A.S.J.) no Wilmer Eye Institute entre janeiro de 2012 a 2014. Os primeiros 21 olhos receberam ar para o tamponamento intraocular após o enxerto do botão endotelial e os 21 olhos seguintes receberam SF6. O desfecho primário medido foi a taxa de descolamento do botão endotelial por análise univariada e multivariada. Resultados: A taxa de descolamento do botão endotelial foi de 67% no grupo que recebeu ar vs 19% no grupo que recebeu SF6 (p<0,05). Não houve nenhum descolamento total de botão e todos os parciais foram tratados com injeção de ar intraocular. Não houve diferença estatística significativa entre os grupos em relação a AV de 20/25 ou melhor (67% vs 71%). A análise univariada demonstrou maior taxa de descolamento com o tamponamento por ar intraocular (OR 8,50, p<0,005) e com botões doadores maiores (OR 14,96, p<0,05). Na análise multivariada, incluindo gás, mas não o tamanho do botão doador, o tipo de gás usado permaneceu sendo um fator preditivo independente e estatisticamente significativo para o desfecho primário, com OR de 6,65 (p<0,05). Porém, quando o tamanho do botão doador foi incluso como covariável, o gás perdeu a sua significância como preditor de descolamento, mantendo o OR de 7,81 (p=0,063), semelhante as análises univariada e multivariada excluindo o tamanho do botão doador. Conclusão: O uso de gás hexafluoreto de enxofre a 20% (SF6) para o tamponamento intraocular reduz a taxa de descolamento do botão endotelial quando comparado ao uso de ar no DMEK.

Pneumatic displacement and intravitreal bevacizumab: a new approach for management of submacular hemorrhage in choroidal neovascular membrane.

Choroidal neovascular membrane (CNVM) is one of the most common causes of submacular hemorrhage (SMH). Conventional treatment involves management of the SMH with pneumatic displacement with or without tissue plasminogen activator (TPA) followed by intravitreal injection of bevacizumab in a second sitting. We decided to assess the efficacy of treating SMH secondary to CNVM with pneumatic displacement using sulphur hexafluoride (SF6) gas and intravitreal bevacizumab. Four patients with SMH secondary to CNVM were included in this study. Intravitreal bevacizumab, 0.05 ml, along with 0.5 ml of SF6 was injected through the pars plana into the vitreous cavity. Postoperative best corrected visual acuity improved in all eyes with complete or partial displacement of SMH out of the foveal area.

The Efficacy of Fluid-Gas Exchange for the Treatment of Postvitrectomy Retinal Detachment

PURPOSE: This study was designed to evaluate the efficacy of fluid-gas exchange for the treatment of postvitrectomy retinal detachment. METHODS: We retrospectively reviewed the records of 33 consecutive patients (35 eyes) who underwent fluid-gas exchange treatment for postvitrectomy retinal detachment using the two-needle pars plana approach technique. RESULTS: The retinal reattachment rate was 80.0% after complete intravitreal gas disappearance following the fluid-gas exchange; the overall success rate was 65.7%. Visual acuity was improved or stable in 80.0% of cases; a two-line or greater vision improvement or a best-corrected visual acuity of 0.4 or better occurred in 62.9% of cases. The success rates for superior retinal detachments and posterior pole retinal detachments were 76.5% and 85.7%, respectively. CONCLUSIONS: Fluid-gas exchange represents a simple and cost-effective alternative outpatient procedure for retinal reattachment without reoperation for the treatment of superior and posterior pole retinal detachments.

Pneumatic retinopexy: principles and practice.

Pneumatic retinopexy (PR) is an alternative to scleral buckling for the surgical repair of selected retinal detachments. A gas bubble is injected into the vitreous cavity, and the patient is positioned so that the bubble closes the retinal break (s), allowing absorption of the subretinal fluid. Cryotherapy or laser photocoagulation is applied around the retinal break(s) to form a permanent seal. The procedure can be done in an outpatient setting, and no incisions are required. A multicenter randomized controlled clinical trial has demonstrated that the anatomic success rate is comparable to scleral buckling, but the morbidity is significantly less with PR. If the macula was detached for less than two weeks, the visual results are significantly better with PR than with scleral buckling. Cataract surgery was required significantly more often following scleral buckling than following PR. Two independent reports have shown that an attempt with PR does not disadvantage the eye; such that the results of scleral buckling after failed PR are not significantly different than primary scleral buckling. A comprehensive review of the world literature on PR revealed 27 statistical series totaling 1,274 eyes. These combined series had a single-operation success rate of 80%, and 98% were cured with reoperations. Pneumatic retinopexy should be considered in cases without inferior or extensive retinal breaks and without significant proliferative vitreoretinopathy. The cost of buckling varies from 4 to 10 times that of PR.

Troca fluido-gasosa pós-vitrectomia via "pars plana" / Fluid gas exchange after \"pars plana\" vitrectomy

Foram observados 30 pacientes com indicaçäo de troca fluido-gasosa pós-vitrectomia via "pars plana". As indicaçöes incluiram proliferaçäo vítreo-retiniana (PVR), rotura gigante, descolamento de retina regmatogênico recorrente, trauma perfurante e descolamento tradicional da retina com com hemorragia vítrea associadas retinopatia diabética proliferativa. Os pacientes foram acompanhados por um período de 3 a 36 meses. Os olhos foram tratados com uma mistura de ar e hexafluoreto de enxofre em concentraçöes variando até 40//de SF. A retina se manteve aplicada em 53//dos casos, sendo que no grupo de proliferaçäo vítreo-retiniana o resultado foi melhor quando associamos a fotocoagulaçäo com laser de argônio

Retinopexia pneumática: quando e onde / Pneumatic retinopexy: where and when

Os autores avaliam 23 olhos de 23 pacientes submetidos à retinopexia pneumática com hexafluoreto de enxofre (SF6), dando-se ênfase ao índice de sucesso anatômico, complicaçöes e indicaçöes. Comparam os resultados obtidos num grupo de pacientes onde a indicaçäo seguia os critérios inicialmente propostos para este procedimento (Grupo I) com os resultados de um grupo onde a indicaçäo näo era clássica (Grupo II). Concluem que a retinopexia pneumática é um procedimento altamente eficaz em casos onde haja uma indicaçäo precisa (90//de sucesso no grupo I) e questionam seu emprego em pacientes que relatam história longa, com proliferaçäo vítreo-retiniana significativa ou que apresentem roturas no terço inferior da retina

Estudo comparativo do comportamento da pressäo intra-ocular após injeçäo de hexafluoreto de enxofre e de ar na câmara vítrea de olhos de coelho / Comparative study of intra-ocular pression behavior after intravitreous injection of SF6 and air in rabbits eyes

Foi realizado estudo comparativo da pressäo intra-ocular após a injeçäo de SF6 e de ar na câmara vítrea de dez coelhos (20 olhos). Os olhos foram separados em dois grupos: - grupo I - olhos direitos, nos quais foi injetado 0,5 ml de SF6 na câmara vítrea. - grupo II - olhos esquerdos, nos quais foi injetado 0,5 ml de ar na câmara vítrea. Os dois gases foram estudados comparativamente quanto ao potencial de alterar o PIO através da tonometria de Schioz. Verificamos que no Grupo I, no qual injetamos o SF6, houve maior aumento de pressäo intra-ocular do que no grupo II em que injetamos o ar e também que o SF6 permaneceu por um período maior na câmara vítrea