Comparison of laser epithelial keratomileusis with and without mitomycin C for wavefront customized surface ablations.

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.

[LASIK interface fluid accumulation caused by glaucoma associated with herpetic keratouveitis: case report]. / Coleção fluídica na interface do LASIK causada por glaucoma secundário à ceratouveíte herpética: relato de caso.

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.

Coleção fluídica na interface do LASIK causada por glaucoma secundário à ceratouveíte herpética: relato de caso / LASIK interface fluid accumulation caused by glaucoma associated with herpetic keratouveitis: case report

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.

Wavefront analysis in Asian-Brazilians.

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.

Intraoperative microkeratome complications in 47,094 laser in situ keratomileusis surgeries.

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.

Confocal microscopy in early diagnosis of Acanthamoeba keratitis.

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.

Refractive outcome of Nidek OPD-scan customized ablations.

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.

Cleaning solutions as a cause of diffuse lamellar keratitis.

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.

Adaptaçäo de auxílios em pacientes com degeneraçäo macular relacionada à idade / Using optical aids in patients with age-related macular degeneration

Auxílios ópticos de perto e de longe foram testados e adaptados em pacientes com Degeneraçäo Macular Relacionada à Idade. A acuidade visual melhorou utilizando-se os auxílios na maioria dos pacientes (78,12 por cento). Os auxílios ópticos mais prescritos para perto foram os óculos com lentes esferoprismáticas e para longe, os mais prescritos foram os telescópios binoculares. Após os testes iniciais e após ter estabelecido o auxílio adequado foram realizados programas de treinamento de aprendizagem do manuseio dos mesmos, antes da prescriçäo final. Verificou-se que a utilizaçäo dos auxílios ópticos possibilitou a realizaçäo

Visäo subnormal em crianças / Low vision in children

Foram estudados 50 casos de visäo subnormal em crianças atendidas no Ambulatório de Estimulaçäo Visual Precoce da Escola Paulista de Medicina, onde foram constatados 42% de casos com etiologia infecciosa e 36% de casos com etiologia hereditária. A principal causa foi a Toxoplasmose Ocular. Ressaltamos a importância de medidas de prevençäo para casos de cegueira parcial evitável e a necessidade de treinamento da visäo residual

Doença de Stargardt: descriçäo de 58 casos atendidos no Setor de Visäo Subnormal da Escola Paulista de Medicina / Stargardt's disease

Estudo de 58 casos da Doença de Stargardt com visäo subnormal, avaliando: a idade de aparecimento dos sintomas, a incidência de acordo com a faixa etária, acuidade visual com e sem auxílio óptico especial, tipos de auxílio para longe e perto prescritos e seus treinamento. Observamos que os sintomas se iniciam até a segunda década. A baixa da acuidade visual dos pacientes näo era muito severa, respondendo bem ao uso do auxílio óptico. Houve indicaçöes de prescriçäo para longe (36,8//) e para perto (63,2//)

Tratamento da visäo subnormal na degeneraçäo macular senil: estudo de 80 casos de Setor da Visäo Subnormal da Escola Paulista de Medicina / Visual rehabilitation in patients with senile macular de generation

Foram estudados retrospectivamente 80 casos com DMS, atendidos num serviço de Visäo Subnormal, sendo avaliado a incidência da patologia em relaçäo ao sexo e idade, acuidade visual inicial e final, número e quais tipos de auxílios ópticos para longe e perto prescritos, e o resultado no uso dos mesmos. Observamos que 5% dos casos näo necessitavam de auxílio óptico, 62,2% obtiveram sucesso satisfatório e insucesso em 33,7%. Houve uma menor aceitaçäo de auxílios para longe (7,5%) do que para perto (57,5%). E destes 77% o faziam utilizando lentes esferoprismáticas ou asféricas montadas em óculos que säo de fácil prescriçäo e aquisiçäo. Discutem-se os fatores que influenciam o sucesso da reabilitaçäo visual em pacientes idosos com DMS