Femtosecond laser-assisted deep anterior lamellar keratoplasty in phototherapeutic keratectomy versus the big-bubble technique in keratoconus

AIM: To compare the functional and anatomic results of femtosecond laser (FSL)-assisted deep anterior lamellar keratoplasty (DALK) associated with phototherapeutic keratectomy (PTK) and FSL-assisted DALK performed using the big-bubble technique in keratoconus. METHODS: During the first phase of the study, an electron microscopy histopathology pilot study was conducted that included four unsuitable donor corneas divided into two groups: in FSL group, FSL lamellar cuts were performed on two corneas and in FSL+ PTK group, PTK was performed at the stromal beds of two corneas after FSL lamellar cuts were made. During the second phase of the study, a randomized clinical trial was conducted that included two treatment groups of patients with keratoconus: group 1 (n= 14 eyes) underwent FSL-assisted DALK associated with PTK and group 2 (n= 12 eyes) underwent FSL-assisted DALK associated with the big-bubble technique. The main outcome measures were the postoperative visual acuity (VA) and optical coherence tomography (OCT) measurements, confocal microscopic findings, and contrast sensitivity. RESULTS: In the pilot study, histopathology showed a more regular stromal bed in the FSL+ PTK group. In the clinical trial, group 1 had significantly worse best spectacle-corrected VA and contrast sensitivity (P< 0.05 for both comparisons). The residual stromal bed measured by OCT was significantly (P< 0.05) thicker in group 1. Confocal microscopy detected opacities only at the donor-receptor interface in group 1. CONCLUSION: Patients with keratoconus treated with FSL-assisted DALK performed using the big-bubble technique fare better than treated with FSL-assisted DALK associated with PTK.Univ Fed Sao Paulo, Escola Paulista Med, Dept Ophthalmol & Visual Sci, BR-04039032 Sao Paulo, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Dept Ophthalmol & Visual Sci, BR-04039032 Sao Paulo, BrazilWeb of Scienc

Influence of a single regional list for corneal transplantation on the eye bank of a university hospital

PURPOSE: To evaluate how the implantation of a single regional list for corneal transplants influenced an eye bank of a university hospital. To analyze the influence of the regional list on the corneas (procurement and destiny), the number of transplantations made and the average waiting time for surgery. METHODS: A retrospective study was made to compare the records of patients who underwent penetrating keratoplasty and also the data of the eye bank of the Medical School of São José do Rio Preto, São Paulo, Brazil. The study compared the data of the service one year before and one year after the creation of the single regional list. RESULTS: The number of transplantations increased from 60 to 92 procedures. The monthly average of directly acquired corneas increased from 13.83 + 6.57 to 18.16 + 4.8 (p-value = 0.07). The number of corneas sent to other institutions was greater than the number of corneas received from other eye banks (p-value = 0.003). There was no significant difference between the waiting time for surgery before and after the creation of the list except for the period of adaptation. CONCLUSIONS: This eye bank served as a supplier of corneas for other institutions. By the end of the first year of operation of the single regional list, there was no alteration in the waiting time as compared to that before its creation. Nonetheless, a tendency of homogenization in the waiting time for penetrating keratoplasty among the patients was observed.OBJETIVO: Avaliar como a implantação do sistema de lista única para transplantes de córnea influenciou um Banco de Olhos vinculado a um hospital escola. Analisar sua interferência nas córneas (captação e destino), no número de transplantes realizados e também na média de tempo de espera pela cirurgia. MÉTODOS: Foi realizado estudo retrospectivo, avaliando os prontuários dos pacientes submetidos a ceratoplastia penetrante e também os dados do Banco de Olhos da Faculdade de Medicina de São José do Rio Preto - SP. O estudo comparou dados relativos ao funcionamento do serviço por um ano antes e após a criação da lista única. RESULTADOS: O número de cirurgias aumentou de 60 para 92 cirurgias. A média mensal de córneas retiradas aumentou de 13,83 ± 6,57 para 18,16 ± 4,80 (p=0,07). O número de córneas enviadas por esta instituição foi maior que o número de córneas recebidas de outros serviços (p=0,003). Não houve diferença significativa entre o tempo de espera pela cirurgia antes e após a criação da fila única (desconsiderando o período de cadastramento). CONCLUSÕES: Este Banco de Olhos funcionou como fornecedor de córneas para outras instituições. Após seu primeiro ano de funcionamento, a implantação da lista única não alterou o tempo de espera dos pacientes pela cirurgia. Apesar disso, evidenciou-se uma tendência à homogeneização do tempo de espera pela ceratoplastia penetrante entre os pacientes.Faculdade de Medicina de São José do Rio Preto Departamento de OftalmologiaUniversidade Federal de São Paulo (UNIFESP) setor de Lente de ContatoFaculdade de Medicina de São José do Rio Preto Departamento de Oftalmologia Setor de Córnea e Moléstias ExternasFaculdade de Medicina de São José do Rio Preto serviço de OftalmologiaUNIFESP, setor de Lente de ContatoSciEL

Efeito tópico de iodo-povidona 0,5% comparado com natamicina 5% em ceratites fúngicas causadas por Fusarium solani em um modelo animal de coelhos: estudo piloto

PURPOSE: To evaluate the efficacy of topical administration of 0.5% povidone-iodine in experimental Fusarium solani keratitis in rabbits. METHODS: Fungal keratitis caused by Fusarium solani was induced in the right eye of 24 New Zealand rabbits. The rabbits were randomly divided into 3 different treatment groups: Group I (povidone-iodine) - treated with topical 0.5% povidone-iodine; Group II (natamycin) - treated with topical 5% natamycin; and Group III (control) - treated with topical saline solution. In all groups the rabbits were treated for three days and then sacrificed. The corneas were excised, macerated and immersed in 10 mL BHI. Culture samples were plated daily on Sabouraud's agar for 7 days, and the number of colony-forming units (CFU) was counted. The rabbits were clinically evaluated during the treatment period. RESULTS: The povidone-iodine and natamycin groups demonstrated better efficacy than the control group based on the number of rabbits with no colonies growing. However, there were no statistically significant differences between the three groups when the number of CFU was analyzed (p>0.05). CONCLUSIONS: Our study demonstrates important methodological considerations in the use of in vivo animal models for the testing of antifungal agents. Using this sample size and methodology of counting CFU, topical 0.5% povidone-iodine demonstrated no benefit in the treatment of experimental Fusarium solani when compared with topical 5% natamycin.OBJETIVO: Avaliar a eficácia do uso tópico de iodo-povidona 0,5% em ceratite experimental por Fusarium solani em coelhos. MÉTODOS: Ceratite fúngica por Fusarium solani foi induzida no olho direito de 24 coelhos da raça New Zealand. Os coelhos foram divididos aleatoriamente em 3 diferentes grupos de tratamento: Grupo I (iodo-povidona) - tratados com iodo-povidona 0,5%; Grupo II (natamicina) - tratados com natamicina 5%; Grupo III (controle) - tratados com solução salina. Os coelhos dos 3 grupos foram tratados por 3 dias e sacrificados em seguida. As córneas foram removidas cirurgicamente, maceradas e incubadas em meio BHI. Semeou-se culturas em placas de ágar Sabouraud, diariamente, durante 7 dias, e contou-se o número de unidades formadoras de colônias (UFC). Os coelhos foram avaliados clinicamente durante o período de tratamento. RESULTADOS: Os grupos iodo-povidona e natamicina demonstraram melhor eficácia do que o grupo controle considerando-se o número de coelhos nos quais não houve crescimento de colônias. Entretanto, não houve diferença estatística significante entre os 3 grupos quando se analizou o número de UFC (p>0,05). CONCLUSÃO: Este estudo demonstrou considerações metodológicas importantes na utilização de modelos animais para o teste de agentes antifúngicos. Usando a metodologia de contar UFC e com este tamanho amostral, administração tópica de iodo-povidona 0,5% não demonstrou benefício do tratamento de ceratite fúngica experimental causada por Fusarium solani quando comparado com a administração tópica de natamicina 5%.Universidade Federal de São Paulo (UNIFESP)University of CaliforniaUNIFESPSciEL

Limbal transplantation at a tertiary hospital in Brazil: a retrospective study

ABSTRACTPurpose:Epidemiological analysis of limbal transplantation surgeries performed in the Ophthalmologic Hospital of Sorocaba.Methods:Retrospective medical records review of 30 patients who underwent limbal stem cell transplants between January 2003 and March 2008. Cases involving conjunctival limbal autograft were classified as group I, and those involving conjunctival limbal allograft as group II.Results:Two patients were excluded due to incomplete data during postoperative follow-up. Of the total sample of 28 patients, 53.6% constituted group I, whereas 46.4% were included in group II. Males were predominant (67.9%), and right eyes were the most prevalent (67.9%). The mean age was 40.3 years. Unilateral cases accounted for 60.7%. The most frequent pathology causing limbal system failure was chemical burns (53%). The mean length of time from diagnosis to surgery was 11.18 years. The limbal graft and amniotic membrane were associated in 75% of all cases, and tarsorrhaphy in 57.1%. The average follow-up period was 24.84 months. The uncorrected visual acuity improved in 38% of the cases, was unchanged in 28.5%, and deteriorated in 33.3%. There was no persistent epithelial defect in 75% of the patients. The conjunctivalization rate was similar between the groups (53.3% and 58.3%, respectively). The transparency improved in only 38.4% of the cases, and 28.5% of the surgeries performed were successful. The most prevalent complication was persistent epithelial defect, which occurred in 25% of the patients, followed by corneal melting in 14.2%. Other complications observed included infectious ulcers, limbal graft necrosis or ischemia, perforation, and descemetocele.Conclusion:Chemical burns remain the main cause of limbal stem cell deficiency. In these cases, limbal transplantation is the standard procedure to restore the ocular surface even though the success rate is low

Antimicrobial Photodynamic Therapy: Study of Bacterial Recovery Viability and Potential Development of Resistance after Treatment

Antimicrobial photodynamic therapy (aPDT) has emerged in the clinical field as a potential alternative to antibiotics to treat microbial infections. No cases of microbial viability recovery or any resistance mechanisms against it are yet known. 5,10,15-tris(1-Methylpyridinium-4-yl)-20-(pentafluorophenyl)-porphyrin triiodide (Tri-Py+-Me-PF) was used as photosensitizer. Vibrio fischeri and recombinant Escherichia coli were the studied bacteria. To determine the bacterial recovery after treatment, Tri-Py+-Me-PF (5.0 μM) was added to bacterial suspensions and the samples were irradiated with white light (40 W m−2) for 270 minutes. Then, the samples were protected from light, aliquots collected at different intervals and the bioluminescence measured. To assess the development of resistance after treatment, bacterial suspensions were exposed to white light (25 minutes), in presence of 5.0 μM of Tri-Py+-Me-PF (99.99% of inactivation) and plated. After the first irradiation period, surviving colonies were collected from the plate and resuspended in PBS. Then, an identical protocol was used and repeated ten times for each bacterium. The results suggest that aPDT using Tri-Py+-Me-PF represents a promising approach to efficiently destroy bacteria since after a single treatment these microorganisms do not recover their viability and after ten generations of partially photosensitized cells neither of the bacteria develop resistance to the photodynamic process