Randomized trial comparing multilayer amniotic membrane transplantation with scleral and corneal grafts for the treatment of scleral thinning after pterygium surgery associated with beta therapy.

PURPOSE: The aim of this study was to compare the use of multilayer amniotic membrane transplantation (AMT) with lamellar corneal transplantation (LCT) and lamellar scleral transplantation (LST) for the treatment of scleral thinning after pterygium surgery associated with beta therapy. METHODS: Twenty-six eyes from 26 different patients with scleral thinning as a consequence of beta therapy after pterygium surgery were evaluated at the Federal University of São Paulo, Brazil. Ophthalmologic examination and ultrasound biomicroscopy were performed to assess scleral thinning before the transplant surgery and then repeated at 30, 90, and 180 days after surgery. An increase in scleral thickness, epithelialization of the ocular surface, and preservation of the ocular globe were the main outcome measures. RESULTS: Irrespective of the surgical technique used (AMT, LCT, or LST), no clinical or statistical changes in corrected distance visual acuity were found in any of the patients during this study. The median preoperative scleral thickness was similar in all 3 groups: AMT = 0.45 mm, LST = 0.48 mm, and LCT = 0.52 mm (P = 0.257); however, 6 months after surgery, the median thickness in the AMT group (0.19) was significantly less than that of the LCT group (0.57) (P = 0.27) or the LST group (0.76) (P = 0.19). Epithelialization occurred in all the patients. CONCLUSIONS: LCT was the best option for the structural treatment of scleral thinning, followed by LST with a conjunctival flap. A high rate of reabsorption was found with AMT, which was the least effective of the 3 therapeutic options and should not be used for this condition.

Tratamento da úlcera escleral pós-cirurgia de pterígio e betaterapia por enxerto de esclera autóloga de espessura parcial / Partial thickness autologus scleral graft for treating scleral ulcers following pterygium excision and betatherapy

OBJETIVO: Avaliação dos resultados da utilização de enxerto de espessura parcial de esclera autóloga para o tratamento das úlceras esclerais profundas, como complicação tardia da exérese de pterígio associada à betaterapia. MÉTODOS: Foram tratados doze olhos de doze pacientes, nove femininos e três masculinos, com idade variando entre 48 e 82 anos, média 65,2 anos. RESULTADOS: Houve boa integração do enxerto em todos os casos, com resultado funcional e cosmético favorável e sem complicações. CONCLUSÃO: Várias técnicas de enxertia tem sido propostas para o tratamento da úlcera escleral: esclera e dura-máter homólogas, derme, cartilagem auricular e periósteo autólogos. No entanto, o procedimento com esclera autóloga apresenta reais vantagens em relaçâo aos enxertos empregados anteriormente. Não há referências na literatura quanto ao emprego de enxerto de esclera autóloga de espessura parcial para o tratamento da úlcera escleral.

OBJETICVE: The authors describes a surgical technique that utilizes autologus delaminated scleral graft for the management of deep scleral ulcers. METHODS: In this technique that were perfomed in 12 eyes of 12 patients, 9 female, 3 male, age from 48 to 82 years, mean age 65.2 years. RESULTS: Occurred good integration of the grafting in all cases without any complications. CONCLUSION: Many techniques have been proposed for the management of scleral ulcers: sclera and dura-mater, autologus derme, auricular cartilage and autologus periosteum.There is no reference in relation to autologus scleral grafting with partial thickness for the treatment of scleral ulcers, as proposed in this study.

Conjunctival autograft alone or combined with adjuvant beta-radiation? A randomized clinical trial.

PURPOSE: To evaluate the effectiveness and safety of postoperative low single-dose of beta-irradiation (ß-RT) in pterygium comparing conjunctival autograft (CAG) surgery with CAG plus adjuvant ß-RT in a randomized clinical trial. METHODS: This trial was designed as a prospective, randomized, single-center study. Surgery was performed in all cases according to the CAG technique. One hundred and eight pterygia were postoperatively randomized to CAG + ß-RT or CAG alone. In the case of ß-RT, a (90) Sr eye applicator was used to deliver 10 Gy to the sclera surface at a dose rate of between 200 and 250 cGy/min. After treatment, both an ophthalmologist and a radiation oncologist performed the follow-up examinations. The accumulated data were analyzed using a group sequential test. RESULTS: Between February 2008 and September 2008, 116 eyes with primary pterygium were operated on according to the trial protocol. Adjuvant treatment was performed within 24 h postoperatively. Eight patients were lost to follow-up, resulting in 108 patients who could be analyzed. At a mean follow-up of 18 months (range, 8-33), in the 54 eyes randomized to receive CAG + ß-RT, 5 relapses occurred compared with 12 recurrences in the 54 eyes in CAG, for a crude control rate of 90.8 % vs. 78%; p = 0.032, respectively. The treatment complications as hyperemia, total dehiscence of the autograft and dellen were significantly more frequent in the CAG (p < 0.05). The arm of ß-RT resulted in better cosmetic results and improves of symptoms than CAG. CONCLUSIONS: A low single-dose of ß-RT of 10 Gy after CAG surgery was a simple, effective, and safe treatment that reduced the risk of primary pterygium recurrence, improved symptoms after surgery, resulting in a better cosmetic effect than only CAG.

Low or high fractionation dose ß-radiotherapy for pterygium? A randomized clinical trial.

PURPOSE: Postoperative adjuvant treatment using ß-radiotherapy (RT) is a proven technique for reducing the recurrence of pterygium. A randomized trial was conducted to determine whether a low fractionation dose of 2 Gy within 10 fractions would provide local control similar to that after a high fractionation dose of 5 Gy within 7 fractions for surgically resected pterygium. METHODS: A randomized trial was conducted in 200 patients (216 pterygia) between February 2006 and July 2007. Only patients with fresh pterygium resected using a bare sclera method and given RT within 3 days were included. Postoperative RT was delivered using a strontium-90 eye applicator. The pterygia were randomly treated using either 5 Gy within 7 fractions (Group 1) or 2 Gy within 10 fractions (Group 2). The local control rate was calculated from the date of surgery. RESULTS: Of the 216 pterygia included, 112 were allocated to Group 1 and 104 to Group 2. The 3-year local control rate for Groups 1 and 2 was 93.8% and 92.3%, respectively (p = .616). A statistically significant difference for cosmetic effect (p = .034), photophobia (p = .02), irritation (p = .001), and scleromalacia (p = .017) was noted in favor of Group 2. CONCLUSIONS: No better local control rate for postoperative pterygium was obtained using high-dose fractionation vs. low-dose fractionation. However, a low-dose fractionation schedule produced better cosmetic effects and resulted in fewer symptoms than high-dose fractionation. Moreover, pterygia can be safely treated in terms of local recurrence using RT schedules with a biologic effective dose of 24-52.5 Gy(10.).

Long-term results and prognostic factors of fractionated strontium-90 eye applicator for pterygium.

PURPOSE: To evaluate the long-term safety, effectiveness, and prognostic factors of fractionated postoperative beta-irradiation. METHODS AND MATERIALS: Between 1993 and 2005, 623 patients with 737 pterygium lesions were treated with a strontium-90 eye applicator after surgical excision. The median follow-up period was 60 months (range, 6.7-139.5). Of the 737 lesions, 644 were primary and 93 were recurrences after surgical removal alone. Fractionated radiotherapy (RT) to a total dose of 35 Gy in five to seven fractions was used. RESULTS: A total of 73 local pterygium recurrences (9.9%) were noted. Of the recurrent cases, 80% were noted within 3 years after treatment. The 5- and 10-year probability of local control was 90% and 88%, respectively. The multivariate analysis for all cases demonstrated that gender, age, total radiation dose, recurrent pterygia, and interval between surgery and RT affected the overall local control rate. Late toxicities that might have been associated with strontium-90 RT included scleromalacia (scleral thinning) in nine eyes, adhesion of the eyelids in eight, cataracts in six, and scleral ulcer in five eyes. CONCLUSION: Fractionated strontium-90 RT to a total dose of approximately 35 Gy in five to seven fractions results in a similar local control rate as higher doses in other series, with an acceptable complication rate.

Determinaçäo das taxas de dose absorvida de aplicadores de 90Sr+90Y / Determination of absorbed dose rates from applicators of 90Sr+90Y

As taxas de dose superficial de dois aplicadores dermatológicos foram determinadas utilizando uma câmara de extrapolação projetada e construída no Laboratório de Calibração do IPEN. Apresenta-se neste trabalho a comparação entre as calibrações realizadas no IPEN e pelo fabricante.

Ulcera de esclera por beta-terapia após tratamento cirúrgico de pterígio / Scleral ulcer due to beta therapy after pterygium surgery

Apresenta-se um caso de ulceraçäo de esclera como complicaçäo tardia de betaterapia, que se manifestou antes de dois anos após tratamento cirúrgico de pterígio, seguida por irradiaçäo. Faz ainda consideraçöes sobre os outros efeitos indesejáveis da beta-terapia ocular bem como sobre a necessidade de critério quanto à indicaçäo cirúrgica e a dose de radiaçäo