ABSTRACT
PURPOSE: To identify the causes of a diffuse lamellar keratitis (DLK) outbreak using a systematic search tool in a case-control analysis. METHODS: An Ishikawa diagram was used to guide physicians to determine the potential risk factors involved in this outbreak. Coherence between the occurrences and each possible cause listed in the diagram was verified, and the total number of eyes at risk was used to calculate the proportion of affected eyes. Multivariate analysis was performed using logistic regression to determine the independent effect of the risk factors, after controlling for confounders and test interactions. RESULTS: All DLK cases were reported in 2007 between June 13 and December 21; during this period, 3,698 procedures were performed. Of the 1,682 flap-related procedures, 204 eyes of 141 individuals presented with DLK. No direct relationship was observed between the occurrence of DLK and the presence of any specific factors; however, flap-lifting enhancements, procedures performed during the morning shift, and non-use of therapeutic contact lenses after the surgery were significantly related to higher occurrence percentages of this condition. CONCLUSIONS: The Ishikawa diagram, like most quality tools, is a visualization and knowledge organization tool. This systematization allowed the investigators to thoroughly assess all the possible causes of DLK outbreak. A clear view of the entire surgical logistics permitted even more rigid management of the main factors involved in the process and, as a result, highlighted factors that deserved attention. The case-control analysis on every factor raised by the Ishikawa diagram indicated that the commonly suspected factors such as biofilm contamination of the water reservoir in autoclaves, the air-conditioning filter system, glove powder, microkeratome motor oil, and gentian violet markers were not related to the outbreak.
Subject(s)
Disease Outbreaks , Keratitis/epidemiology , Keratitis/etiology , Keratomileusis, Laser In Situ/adverse effects , Risk Assessment/methods , Adult , Brazil/epidemiology , Female , Humans , Male , Middle Aged , Multivariate Analysis , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Risk Factors , Surgical Flaps/adverse effects , Time Factors , Treatment Outcome , Young AdultABSTRACT
ABSTRACT Purpose: To identify the causes of a diffuse lamellar keratitis (DLK) outbreak using a systematic search tool in a case-control analysis. Methods: An Ishikawa diagram was used to guide physicians to determine the potential risk factors involved in this outbreak. Coherence between the occurrences and each possible cause listed in the diagram was verified, and the total number of eyes at risk was used to calculate the proportion of affected eyes. Multivariate analysis was performed using logistic regression to determine the independent effect of the risk factors, after controlling for confounders and test interactions. Results: All DLK cases were reported in 2007 between June 13 and December 21; during this period, 3,698 procedures were performed. Of the 1,682 flap-related procedures, 204 eyes of 141 individuals presented with DLK. No direct relationship was observed between the occurrence of DLK and the presence of any specific factors; however, flap-lifting enhancements, procedures performed during the morning shift, and non-use of therapeutic contact lenses after the surgery were significantly related to higher occurrence percentages of this condition. Conclusions: The Ishikawa diagram, like most quality tools, is a visualization and knowledge organization tool. This systematization allowed the investigators to thoroughly assess all the possible causes of DLK outbreak. A clear view of the entire surgical logistics permitted even more rigid management of the main factors involved in the process and, as a result, highlighted factors that deserved attention. The case-control analysis on every factor raised by the Ishikawa diagram indicated that the commonly suspected factors such as biofilm contamination of the water reservoir in autoclaves, the air-conditioning filter system, glove powder, microkeratome motor oil, and gentian violet markers were not related to the outbreak.
RESUMO Objetivos: Identificar as causas de um surto de ceratite lamelar difusa (DLK) utilizando uma ferramenta de busca sistemática em uma análise de caso-controle. Métodos: O diagrama de Ishikawa foi usado para orientar os médicos a identificar os potenciais fatores de risco envolvidos neste surto. Coerência entre as ocorrências e cada causa possível listada no diagrama foi verificada. O número total de olhos em risco foi usada para calcular a percentagem de olhos afetados. A análise multivariada foi realizada por meio de regressão logística para determinar o efeito independente dos fatores de risco, controle de fatores de confusão e interações de teste. Resultados: Todos os casos de ceratite lamelar difusa foram relatados em 2007 entre 13 de junho e 21 de dezembro, durante este tempo foram realizados no total 3.698 procedimentos. De um total de 1.682 procedimentos relacionados a confecção de um flap, 204 olhos de 141 indivíduos apresentaram ceratite lamelar difusa. Não foi observada relação direta entre a ocorrência de ceratite lamelar difusa e a presença de qualquer fator específico; no entanto, procedimentos que incluíam um novo levantamento do flap, procedimentos realizados no turno da manhã, e o não-uso de lentes de contato terapêuticas após a cirurgia foram significativamente relacionados com a ocorrência desta complicação. Conclusão: O diagrama de Ishikawa é uma ferramenta de visualização e organização do conhecimento. Essa sistematização permitiu aos investigadores pesquisar todas as possíveis causas do surto de ceratite lamelar difusa. Uma visão clara de toda a logística cirúrgica permitiu a gestão mais rígida dos principais fatores envolvidos no processo. A análise de caso-controle em relação a cada fatores levantados pelo diagrama indicou que fatores sempre suspeitos, tais como: contaminação do biofilme da água do reservatório das autoclaves, sistema de filtro de ar-condicionado, pó de luva, óleo de motor do microcerátomo e marcador violeta de genciana, não foram relacionados com o surto.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Young Adult , Disease Outbreaks , Risk Assessment/methods , Keratomileusis, Laser In Situ/adverse effects , Keratitis/etiology , Keratitis/epidemiology , Postoperative Complications/etiology , Postoperative Complications/epidemiology , Surgical Flaps/adverse effects , Time Factors , Brazil/epidemiology , Multivariate Analysis , Risk Factors , Treatment OutcomeABSTRACT
PURPOSE: To investigate the efficacy of mitomycin C (MMC) in preventing haze formation in surface wavefront customized ablations with successful refractive treatment (laser epithelial keratomileusis [LASEK]) and to evaluate the safety of this technique on corneal stroma and endothelium. METHODS: This study was a prospective, double-masked, randomized clinical trial involving 52 eyes (30 placebo and 22 MMC) of 26 patients. The manifest refractive spherical equivalent (MRSE), best spectacle-corrected visual acuity, uncorrected visual acuity, corneal pachymetry, topography, aberrometry, endothelial specular microscopy, contrast sensitivity, corneal confocal microscopy, and complaints of pain via a subjective questionnaire were recorded preoperatively and 90 days postoperatively. RESULTS: The mean MRSE at 90 days postoperatively was -0.56 diopters (D) (-4.95 +/- 1.85 D, range: -8.00 to -1.62 D) for the MMC group and -0.49 D (-4.51 +/- 1.81 D, range: -7.75 to -2.25 D) for the placebo group. Higher order aberrations were similar between the placebo and MMC groups 90 days postoperatively (0.538 +/- 0.228 microm and 0.478 +/- 0.134 microm, respectively). Analysis of the endothelial cell count indicated a statistically significant decrease in endothelial cell density (P = .017) after LASEK, independent of MMC use. CONCLUSIONS: The predictability of the final target refraction, induction of high order aberrations, and improvement in contrast sensitivity proved that the use of MMC was equally safe when compared to procedures that did not use MMC. In addition, the procedure was efficient in the prevention of corneal haze.
Subject(s)
Corneal Opacity/prevention & control , Diagnostic Techniques, Ophthalmological , Keratectomy, Subepithelial, Laser-Assisted/adverse effects , Mitomycin/therapeutic use , Nucleic Acid Synthesis Inhibitors/therapeutic use , Preoperative Care , Adult , Cell Count , Contrast Sensitivity , Cornea/pathology , Corneal Opacity/etiology , Double-Blind Method , Endothelium, Corneal/pathology , Female , Humans , Male , Microscopy, Confocal , Mitomycin/adverse effects , Nucleic Acid Synthesis Inhibitors/adverse effects , Postoperative Period , Predictive Value of Tests , Refraction, Ocular , Treatment OutcomeABSTRACT
Herpes simplex virus infection is a frequent cause of intraocular inflammation or anterior uveitis. Ocular hypertension is a common feature in herpetic keratouveitis. We describe a fluid accumulation and flap displacement in late postoperative period (28 months) of LASIK associated with ocular hypertension caused by herpetic keratouveitis. This finding supports the theory that flap attachment after LASIK is only partial and the virtual space remains indefinitely. The presence of ocular hypertension may lead to corneal edema and fluid accumulation in the interface.
Subject(s)
Corneal Edema/etiology , Glaucoma/complications , Keratitis, Herpetic/complications , Keratomileusis, Laser In Situ , Postoperative Complications , Uveitis/complications , Aqueous Humor , Glaucoma/etiology , Humans , Male , Middle Aged , Uveitis/virologyABSTRACT
A infecção por Herpes simplex vírus (HSV) é causa freqüente de inflamação intra-ocular ou uveíte anterior. A hipertensão ocular é característica comumente observada nas ceratouveítes herpéticas. Neste relato descrevemos o acúmulo de fluido e descolamento do "flap" corneano da ceratomileusis, no pós-operatório tardio de LASIK (28 meses), associado a quadro hipertensivo ocular secundário a ceratouveíte herpética. Este achado corrobora a suposição que a cicatrização corneana após LASIK seja apenas parcial e o espaço virtual produzido pela ceratomileuisis permaneça indefinidamente. Condições de aumento excessivo da pressão intra-ocular podem causar edema corneano com acúmulo de fluido da interface.
Herpes simplex virus infection is a frequent cause of intraocular inflammation or anterior uveitis. Ocular hypertension is a common feature in herpetic keratouveitis. We describe a fluid accumulation and flap displacement in late postoperative period (28 months) of LASIK associated with ocular hypertension caused by herpetic keratouveitis. This finding supports the theory that flap attachment after LASIK is only partial and the virtual space remains indefinitely. The presence of ocular hypertension may lead to corneal edema and fluid accumulation in the interface.
Subject(s)
Humans , Male , Middle Aged , Corneal Edema/etiology , Glaucoma/complications , Keratomileusis, Laser In Situ , Keratitis, Herpetic/complications , Postoperative Complications , Uveitis/complications , Aqueous Humor , Glaucoma/etiology , Uveitis/virologyABSTRACT
PURPOSE: To compare the distribution of ocular higher order wavefront aberrations (third to sixth order) in the Brazilian population of Asian and non-Asian refractive surgery patients. METHODS: Preoperative refractive and wavefront data were reviewed for 648 eyes in 324 patients who underwent custom ablation at the Excimer Laser Santa Cruz refractive surgery center in São Paulo, Brazil, from March 2002 to July 2005. Patients were divided into two groups: Asian patients and non-Asian patients, based on family history. Statistical analysis was performed to assess the differences between the groups with respect to manifest refractive spherical equivalent, astigmatism, pachymetry, OPD-root-square-mean (RMS) for a 6.0-mm pupil, total wavefront aberrations, third- to sixth-order higher order aberrations, and individual aberrations. RESULTS: The mean spherical equivalent refraction in the Asian group of -4.38 diopters (D) was significantly higher than the spherical equivalent refraction of -3.46 D in the non-Asian group (t= -4.32; P=.00001). Comparison of the differences between groups with respect to higher order aberrations, coma, trefoil, quadrafoil, spherical aberration, higher order astigmatism, and pachymetry was not statistically significant. CONCLUSIONS: Asian patients have a higher prevalence of myopia than non-Asian patients. No differences were noted in higher order aberrations between Asian and non-Asian patients.
Subject(s)
Astigmatism/ethnology , Myopia/ethnology , Preoperative Care/methods , Refraction, Ocular , Adult , Asian People/ethnology , Astigmatism/diagnosis , Brazil/epidemiology , Cornea/pathology , Diagnostic Techniques, Ophthalmological/instrumentation , Humans , Lasers, Excimer , Myopia/diagnosis , Photorefractive Keratectomy/methods , Retrospective StudiesABSTRACT
PURPOSE: We evaluated the incidence and intraoperative microkeratome-related complications in laser in situ keratomileusis (LASIK). METHODS: We present non-randomized, retrospective, comparative, interventional case series. We reviewed the records of patients who underwent LASIK from August 2000 to March 2004 at Excimer Laser Santa Cruz, São Paulo, Brazil (47,094 eyes). We identified 369 eyes (0.0078%) with an intraoperative complication. Data were collected regarding microkeratome, average keratometric power, and type of complication. RESULTS: The Hansatome microkeratome was the most common microkeratome used (34,182 eyes; 73%), followed by the Automated Corneal Shaper-ACS (11,164 eyes, 24%) and the Nidek MK-2000 (1748 eyes, 3.7%). Intraoperative complications were more common with the ACS (1.26%) than with the Hansatome (0.63%) and MK-2000 (0.63%) (P<.001; P=.03; respectively). Complications included incomplete flaps (0.23%), buttonholes (0.13%), thin flaps (0.08%), and free flaps (0.08%). Buttonholes were more frequent with the ACS (0.34%) than with the Hansatome (0.06%) (P<.001) and free flaps were more common with the ACS (0.20%) and MK-2000 (0.29%) than with the Hansatome (0.04%) (P<.001). Keratometric power of eyes with intraoperative complications was significantly higher in the ACS group compared to the Hansatome group. CONCLUSIONS: Intraoperative complications were more common with the ACS than with the Hansatome or MK-2000. Buttonholes were most frequent with the ACS, and the Hansatome had the lowest incidence of free flaps.
Subject(s)
Corneal Stroma/pathology , Intraoperative Complications , Keratomileusis, Laser In Situ/adverse effects , Surgical Flaps/pathology , Humans , Incidence , Refractive Surgical Procedures , Retrospective StudiesABSTRACT
PURPOSE: This study correlated confocal microscopic images obtained using the Nidek ConfoScan 2.0 System in corneas with clinical suspicion of Acanthamoeba keratitis, with diagnosis confirmed by either cytological and/or histological analysis. METHODS: Fifteen eyes of 14 patients with a clinical diagnosis of Acanthamoeba keratitis underwent confocal microscopy evaluation. RESULTS: Fifteen eyes of 14 patients (one bilateral case) showed Acanthamoeba keratitis alterations that ranged from massive infestation to cicatricial opacity in the stroma. Ten patients (71%) were females. Mean age was 26 years (range 19 to 37 yr). All patients were contact lens wearers. CONCLUSION: Confocal microscopy was a useful, noninvasive technique in the diagnosis and treatment of Acanthamoeba keratitis, especially in those cases in which corneal scraping, cytological analysis, and culture are negative. It also eliminated the necessity of tissue biopsy, considered an invasive procedure.
Subject(s)
Acanthamoeba Keratitis/diagnosis , Diagnostic Techniques, Ophthalmological , Microscopy, Confocal/methods , Adult , Cornea/innervation , Humans , Infant , Male , Ophthalmic Nerve/parasitologyABSTRACT
PURPOSE: Custom ablation is an improved refractive laser treatment that aims to optimize the optical system of the eye. We report preliminary results of laser in situ keratomileusis (LASIK) using customized ablation and the Nidek OPD-Scan. METHODS: We report a prospective, non-comparative interventional case series. After OPD-Scan analysis, patients underwent LASIK. Eighty-four eyes were included: 44 eyes were treated with Flex Scan, 22 eyes with customized ablation based on Nidek OPD-Scan analysis, and 18 eyes were treated with conventional (scanning slit) ablation. RESULTS: Visual outcome did not differ among groups. No patient experienced a significant decrease (more than 1 Snellen line) in best spectacle-corrected visual acuity. CONCLUSIONS: LASIK with the Nidek OPD-Scan system was safe and effective in this small group of patients.
Subject(s)
Keratomileusis, Laser In Situ/methods , Refractive Surgical Procedures , Cornea/surgery , Corneal Topography/methods , Female , Humans , Male , Prospective Studies , Refraction, Ocular , Safety , Treatment Outcome , Visual AcuityABSTRACT
PURPOSE: To assess the capability of two microkeratome cleaning solutions in causing diffuse lamellar keratitis (DLK) in a rabbit model of laser in situ keratomileusis (LASIK). METHODS: Two cleaning solutions (Palmolive 2:100 and Cidezyme 2:250) were tested. These solutions were diluted with balanced salt solution according to directions from the Hansatome microkeratome manual. Two additional solutions were prepared using an additional ten-fold dilution, creating a total of four study solutions. A LASIK flap was created in one eye each of 25 rabbits using the ALK Chiron microkeratome. The rabbits were divided into five study groups. The flaps were reflected and a drop of one of the study solutions (or BSS, control group) was placed on the interface. After 1 minute, the solution was washed out from the interface and the flap was repositioned. The eyes were examined at the slit lamp on postoperative days 1, 2, 3, 5, and 7. RESULTS: In 12 eyes, a flap displacement was identified. Four eyes showed flap retraction and five others, epithelial ingrowth in flap margins. The incidence of these events did not differ among groups. Thirteen eyes were then evaluated for DLK. No DLK-like interface inflammation was seen in the studied eyes. CONCLUSION: The cleaning solutions, when diluted as recommended by the microkeratome manufacturer, when in contact with the corneal stroma, and provided that the interface was washed with BSS did not cause DLK interface inflammation in rabbit LASIK models.
Subject(s)
Corneal Stroma/drug effects , Detergents/adverse effects , Keratitis/chemically induced , Surgical Flaps , Animals , Keratomileusis, Laser In Situ , Rabbits , Refractive Surgical ProceduresABSTRACT
Objetivo: Estudar a mucosa enxertada em bulbo ocular para correçäo de simbléfaro severo. Material e Método: Dez pacientes, três do sexo feminino e sete do masculino, com idade entre 26 e 68 anos (média de 47,5 anos)que apresentavam simbléfaro severo foram submetidos a enxerto de mucosa labial, no período de julho de 1989 a agosto de 1995. As causas de simbléfaro foram: pterígio recidivado, sindrome de Stevens-Johnson e conjutivite cicatricial crônica. Resultado: Após a cicatrizaçäo da mucosa enxertada, esta foi biopsiada e os resultados dos exames anatomopatólogicos demonstraram epitélio pavimentoso estratificado, näo queratinizado na totalidade dos casos, sendo que em 90 por cento dos pacientes estudados o infiltrado inflamatório foi discreto com predominio celular de linfócitos. Conclusäo: Acreditamos que o enxerto de mucosa labial sirva para refazer os fundos de saco, sendo um material de fácil obtençäo. Pode ser retirado em quantidades suficientes para recobrir toda a área da conjuntiva bulbar. O enxerto de mucosa labial apresenta bons resultados para tratamento de pacientes com simbléfaro severo e näo muda suas caracterísiticas histológicas após a enxertia
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Eye Burns/diagnosis , Eyelids/pathology , Tissue TransplantationABSTRACT
Foram examinados 390 pacientes com queixa de queda da pálpebra superior no setor de Plástica Ocular da Universidade de Säo Paulo - Escola Paulista de Medicina, no período de janeiro 1985 a fevereiro 1995. Encontrou-se 68,9 por cento de ptose congênita, 22,8 por cento de ptose adquirida e 8,2 por cento de pseudoptose. Com relaçäo ao sexo, 54,8 por cento eram do sexo masculino e 45,1 por cento do sexo feminino. O estudo dos pacientes com ptose congênita mostrou: ambliopia em 5,9 por cento; fenômeno de Marcus Gunn em 5,3 por cento e síndrome de blefarofimose em 6,3 por cento. Alteraçäo na motilidade ocular extrínseca estava presente em 30 por cento dos casos de ptose congênita e 29 por ceneto de ptose adquirida. A alteraçäo palpebral mais comum foi o epicanto inverso. Os autores analisam as alteraçöes oculares e palpebrais associadas ao quadro de ptose palpebral
Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Blepharoptosis , Eye Manifestations , Aged, 80 and over , Amblyopia , Blepharophimosis , StrabismusABSTRACT
Säo apresentados cinco casos de "Floppy Eyelid Syndrome", com respectivas descriçöes clínicas e condutas terapêuticas. Faz-se uma ampla revisäo da literatura sobre o assunto e propöe-se o nome de "Síndrome da Flacidez da Pálpebra Superior" para ser adotado em nosso meio
Subject(s)
Humans , Male , Female , Middle Aged , Conjunctivitis, Allergic/etiology , Eyelids/abnormalities , Eyelid Diseases/etiology , Eyelid Diseases/physiopathologyABSTRACT
Foi realizado um estudo retrospectivo de 8 pacientes portadores de ceratomicoses submetidos a transplante de córnea penetrante terapêutico, no sentido de avaliar as dificuldades técnicas, os resultados visuais e as principais complicaçöes. A indicaçäo do transplante foi feita nos casos de piora da lesäo apesar do tratamento clínico. A duraçäo da terapêutica medicamentosa com natamicina colírio e ketoconazol oral antes da cirurgia variou de 4 a 15 dias. Todos os pacientes apresentavam acuidade visual (AV) pré-operatória menor que movimento de mäos. 50% obtiveram AV pós-operatória igual ou maior que 20/50. As principais complicaçöes foram a catarata (50%) e a opacificaçäo do transplante (37,5%). Um paciente (12,5%) evoluiu para atrofia ocular e um (12,5%) para evisceraçäo, devido à progressäo da endoftalmite
Subject(s)
Adult , Middle Aged , Humans , Male , Female , Cornea/transplantation , Mycoses/surgery , Corneal Ulcer/surgery , Administration, Oral , Administration, Topical , Atropine/administration & dosage , Ketoconazole/administration & dosage , Postoperative Care , Postoperative Complications , Ophthalmic Solutions/administration & dosageABSTRACT
Estudamos retrospectivamente 11 crianças operadas de catarata monocular, nas quais foram implantadas lentes intraoculares de câmara posterior. Cinco pacientes (45.5%) apresentavam catarata infantil e seis pacientes (54.5%) catarata traumática. Em 4 pacientes (36%) apresentavam acuidade visual entre 20/50 e 20/100, 1 paciente (9%) 20/200 e pacientes näo informavam a acuidade visual. O implante de lente introcular em crianças é uma opçäo no tratamento de casos bem selecionados de catarata monocular