Corneal ectasia following photorefractive keratectomy: a confocal microscopic case report and literature review / Ectasia corneana após ceratectomia fotorrefrativa: relato de caso de microscopia confocal e revisão da literatura

ABSTRACT The occurrence of corneal ectasia after photorefractive keratectomy is a rare but serious complication of refractive surgery. Possible risk factors are not well assessed, but a probable reason is the failure to detect keratoconus preoperatively. In this report, we describe a case of corneal ectasia after photorefractive keratectomy in a patient who presented a suspicious tomography pattern preoperatively but had no degenerative alterations associated with pathologic keratoconus, as revealed by in vivo corneal confocal microscopy. We also review eligible case reports of post-photorefractive keratectomy ectasia to find similar characteristics.

RESUMO A ocorrência de ectasia corneana após ceratectomia fotorrefrativa é uma complicação rara, porém grave, em cirurgia refrativa. Os possíveis fatores de risco não são bem avaliados, mas a opinião atual é que a falha na detecção de ceratocone pré-operatório possa ser o principal motivo. Neste relato, descrevemos um caso de ectasia corneana após ceratectomia fotorrefrativa em paciente apresentando padrão tomográfico suspeito no pré-operatório, mas sem alterações degenerativas associadas a ceratocone patológico, conforme revelado por microscopia confocal in vivo da córnea. Além disso, revisamos, na literatura, relatos de casos elegíveis de ectasia pós-ceratectomia fotorrefrativa para encontrar características semelhantes.

Mycobacterium abscessus keratitis after LASIK surgery / Ceratite por Mycobacterium abscessus após cirurgia LASIK

ABSTRACT A 33-year-old male presented with unilateral subacute infectious keratitis 4 weeks after surgery. Corneal inflammation was resistant to standard topical antibiotic regimens. During diagnostic flap lifting and sampling, the corneal flap melted and separated. Through flap lifting, corneal scraping, microbiological diagnosis of atypical mycobacteria, and treatment with topical fortified amikacin, clarithromycin, and systemic clarithromycin, clinical improvement was achieved.

RESUMO Paciente do sexo masculino, 33 anos, apresentou ceratite infecciosa subaguda unilateral 4 semanas após a cirurgia. A inflamação da córnea foi resistente aos regimes de antibióticos tópicos padrão. A aba da córnea foi derretida e seccionada durante o levantamento e amostragem para diagnóstico. A melhora clínica só foi alcançada após levantamento do retalho, raspagem e diagnóstico microbiológico de micobactérias atípicas e tratamento com amicacina fortificada tópica, claritromicina e claritromicina sistêmica.

Corneal reshaping: an experiment with a type I collagen-based vitrigel for remodeling porcine corneas / Remodelamento corneano: relato de um experimento com um vitrigel a base de colágeno tipo I para remodelamento de córneas porcinas

ABSTRACT Purpose: This study aimed to report an experiment designed to determine anatomical changes in porcine corneas following placement of a novel polymer implant into the cornea. Methods: An ex vivo porcine eye model was used. A novel type I collagen-based vitrigel implant (6 mm in diameter) was shaped with an excimer laser on the posterior surface to create three planoconcave shapes. Implants were inserted into a manually dissected stromal pocket at a depth of approximately 200 μm. Three treatment groups were defined: group A (n=3), maximal ablation depth 70 μm; Group B (n=3), maximal ablation depth 64 μm; and group C (n=3), maximal ablation depth 104 μm, with a central hole. A control group (D, n=3) was included, in which a stromal pocket was created but biomaterial was not inserted. Eyes were evaluated by optical coherence tomography (OCT) and corneal tomography. Results: Corneal tomography showed a trend for a decreased mean keratometry in all four groups. Optical coherence tomography showed corneas with implants placed within the anterior stroma and visible flattening, whereas the corneas in the control group did not qualitatively change shape. Conclusions: The novel planoconcave biomaterial implant described herein could reshape the cornea in an ex vivo model, resulting in the flattening of the cornea. Further studies are needed using in vivo animal models to confirm such findings.

RESUMO Objetivo: Relatar um experimento projetado para determinar alterações anatômicas em córneas porcinas após a colocação de um novo implante de polímero na córnea. Métodos: Foi utilizado olho de porco ex vivo. Um novo agente modelador biocompatível, de colágeno tipo 1, com 6mm de diâmetro foi moldado com excimer laser em sua face posterior, para criar três formatos planocôncavos. Os implantes foram inseridos dentro de um bolsão, dissecado manualmente, a 200 micrômetros (μm). Foram definidos três grupos de tratamento: grupo A (n=3), teve a profundidade máxima de ablação de 70 μm; o grupo B (n=3), profundidade máxima de ablação de 64 μm; e o grupo C (n=3), profundidade máxima de ablação de 104 μm, com buraco central. O grupo controle, D (n=3), foi incluído, com a criação do bolsão estromal, porém sem inserir o material. A avaliação desses olhos foi realizada por tomografia de coerência óptica (OCT) e por tomografia corneana. Resultados: A tomografia corneana mostrou uma tendência para diminuição da ceratometria média em todos os 4 grupos. A tomografia de coerência óptica mostrou córneas com implantes localizados no estroma anterior e aplanamento visível, enquanto as córneas não mudaram qualitativamente o formato no grupo controle. Conclusões: O novo implante de biomaterial planocôncavo descrito aqui foi capaz de remodelar a córnea em modelo de animal ex vivo, resultando no aplanamento corneano. Novos estudos são necessários usando modelos animais in vivo para confirmar tais achados.

Ten-year follow-up of corneal cross-linking and refractive surface ablation in patients with asymmetric corneal topography

Purpose: Compare the safety and efficacy of wavefront?guided photorefractive keratotomy (PRK) 6 months after cross?linking (CXL) to wavefront?guided PRK alone for refractive correction in patients with bilateral asymmetric corneal topography. Methods: Prospective randomized clinical trial with 16 patients (32 eyes). CXL with subsequent PRK after 6 months in one eye, and PRK alone was performed in contralateral eyes. The follow?up was 10 years. We analyzed visual outcomes, Scheimpflug topography, and corneal haze evaluation. Results: Eyes in the PRK group showed better results than in the CXL + PRK group. Mean postoperative CDVA was 0.044 logmar (SD, 0.073) in the PRK group and 0.1 logmar (SD, 0.21) in the CXL + PRK group, the mean sphere was + 0.21 (SD, 0.6) D in the PRK group and 0.87 (SD, 2.3) D in the CXL + PRK group, and mean SE was ?0.35 (SD, 0.65) D in the PRK group and 0.62 (SD, 2.32) D in the CXL + PRK group. In one patient, a steepening of 2.5 D and a thinning of 17 ?m occurred in PRK alone group. Two patients in the CXL + PRK group presented corneal haze. The overall complication rate was 18,75% (haze and ectasia). Conclusion: Non?simultaneous CXL and PRK procedures yielded good refractive results, but worse than those obtained with PRK alone. Although one patient in the PRK group developed corneal ectasia, the CXL + PRK group had a higher loss of vision lines, indicating less safety

Aberraciones corneales en pacientes con indicación de cirugía refractiva con láser de excímeros

Objetivo: Determinar las aberraciones corneales en pacientes con indicación de cirugía refractiva con láser de excímeros. Métodos: Se realizó un estudio retrospectivo, transversal, descriptivo, con 161 ojos de 81 pacientes adultos, de ambos sexos con indicación de cirugía con láser de excímeros para la corrección de su defecto refractivo. Se definieron como variables edad, sexo, desenfoque, astigmatismo, coma, trefoil y aberración esférica, las que se determinaron por el estudio topográfico de rutina con el topógrafo KeratronTM Scout, Optikon. Resultados: Se obtuvieron los siguientes valores promedios: desenfoque -4,17 ± 0,29 D (-16,15 a 8,5 D) y absoluto 4,94 ± 0,199 (10 a 16,5 D), astigmatismo -1,56 ± 0,09 D (-9,44 a -0,09 D), coma 0,25 ± 0,016 (0,01 a 1,5 D), trefoil 0,204 ± 0,016 (0,01 a 1,18 D) y aberración esférica 0,316 ± 0,018 D (0,0 a 1,27D). En el 75 % de los casos los valores absolutos de desenfoque fueron inferiores a 6,56, de astigmatismo inferior a 0,33 D, de coma menor que 0,33, trefoil inferior a 0,25 y aberraciones esféricas menores que 0,32 D. Conclusiones: Los valores promedio de las aberraciones corneales desenfoque, astigmatismo, coma, trefoil y aberración esférica se encuentran en el rango de los valores reportados en la literatura científica y la distribución de los valores de las aberraciones corneales presentan desplazamiento de la mayoría de los casos hacia los valores más bajo del rango de determinación.

Objective: To determine corneal aberrations in patients indicated for excimer laser refractive surgery. Methods: A retrospective, cross-sectional and descriptive study was carried out with 161 eyes of 81 adult patients of both sexes with indication of excimer laser surgery for the correction of their refractive defect. Age, sex, defocus, astigmatism, coma, trefoil and spherical aberration were defined as variables, determined by routine topographic study with the KeratronTM Scout topographer, Optikon. Results: The following average values were obtained: defocus of -4.17 ± 0.29 D (-16.15 to 8.5 D) and absolute of 4.94 ± 0.199 (10 to 16.5 D), astigmatism of -1.56 ± 0.09 D (-9.44 to -0.09 D), coma of 0.25 ± 0.016 (0.01 to 1.5 D), trefoil of 0.204 ± 0.016 (0.01 to 1.18 D) and spherical aberration of 0.316 ± 0.018 D (0.0 to 1.27D). In 75 % of the cases, the absolute values for defocus were lower than 6.56; for astigmatism, lower than 0.33 D; for coma, lower than 0.33; for trefoil, lower than 0.25; and for spherical aberrations, lower than 0.32 D. Conclusions: The average values of corneal aberrations for defocus, astigmatism, coma, trefoil and spherical aberration are in the range of values reported in the scientific literature, while the distribution of corneal aberrations values present displacement of most of the cases towards the lower values of the determination range.

Clinical outcomes of epithelial ingrowth following laser in situ keratomileusis with mechanical debridement and compressed heating air flow: a case series / Resultado visual do tratamento do crescimento epitelial após laser in situ ceratomileuse através da remoção mecânica e aplicação de ar comprimido aquecido: série de casos

ABSTRACT Purpose: To describe the clinical outcomes of manual scraping of epithelial ingrowth followed by compressed heating air flow after laser in situ keratomileusis (LASIK). Methods: We underwent a retrospective, noncomparative, and interventional case series. Twenty eyes of 17 patients were included in this study. Each patient with a history of LASIK underwent epithelial removal with mechanical debridement followed by compressed heating air flow. Our primary outcome was the recurrence of epithelial ingrowth after 3 months of follow-up, while our secondary outcomes were uncorrected distance visual acuity, corrected distance visual acuity, and complications after surgery. Results: Ten patients (58.8%) were male, and eight eyes of seven (41.2%) patients underwent primary LASIK surgery, while12 eyes of 10 patients had flap-lift retreatment LASIK; sixteen eyes (80.0%) underwent mechanical microkeratome LASIK and four (20.0%) underwent femtosecond laser-assisted LASIK. Mean age at surgical removal of epithelial ingrowth was 37.0 years ± 9.3 years (range 24 to 55 years). There was recurrence of ingrowth in two eyes (10%) after 3 months of follow-up. The mean corrected distance visual acuity of patients before surgery was 0.07 ± 0.09 logMAR, and after the last follow-up was 0.02 ± 0.04 logMAR (p=0.06). The odds ratio of presenting with epithelial ingrowth after LASIK enhancement compared to primary LASIK was 29.41. Conclusion: Manual scraping followed by compressed heating air flow is a safe and effective treatment of clinically significant epithelial ingrowth after LASIK. At the last follow-up, no eye lost any line in corrected distance visual acuity.

RESUMO Objetivo: Descrever os resultados clínicos do tratamento do crescimento epitelial através da técnica de remoção manual seguido da utilização de um compressor de ar comprimido aquecido após a cirurgia de laser in situ keratomileusis (LASIK). Métodos: Vinte olhos de 17 pacientes foram incluídos no estudo. Cada paciente havia sido submetido a cirurgia de LASIK com presença de crescimento epitelial e foi submetido a tratamento cirúrgico para sua retirada. O objetivo primário foi identificar a presença de crescimento epitelial recorrente ao final de 3 meses de seguimento. Os objetivos secundários foram as medidas de acuidade visual sem correção, acuidade visual com correção, e complicações pós-operatórias. Resultados: Dez pacientes (58,8%) eram homens e 7 mulheres. Oito olhos de sete (41,2%) pacientes apresentavam cirurgia de LASIK primária e 12 olhos de 10 pacientes tinham cirurgia de LASIK com retratamento; dezesseis olhos (80%) utilizaram microcerátomo manual e quatro (20%) laser de femtosegundo. A média de idade no momento da cirurgia de remoção do epitélio era de 37,0 anos ± 9,3 (DP) (variando de 24 a 55 anos). Ocorreu recidiva do crescimento epithelial em dois olhos (10%) após 3 meses de seguimento. A acuidade visual sem correção antes da cirurgia era de 0,07 ± 0,09 logMAR, e após a cirurgia passou para 0,02 ± 0,04 logMAR (p=0,06). A chance (odds ration) de aparecimento do crescimento epithelial após uma reoperação de LASIK é 29,41 vezes maior do que no LASIK primário. Conclusão: A técnica de remoção epitelial manual seguida da utilização de ar comprimido aquecido é segura e efetiva no tratamento do crescimento epitelial após LASIK. Ao final do último acompanhamento, nenhum olho apresentou perda de linhas de visão.

Femtosecond laser-assisted laser in situ keratomileusis for the correction of high myopia in Meesmann corneal dystrophy: a case report / Femto-LASIK para correção de alta miopia na distrofa corneana de Meesmann: relato de caso

ABSTRACT The patient was a 26-year-old woman who had manifest refraction and uncorrected and corrected distance visual acuities of -7.00 × -4.50 at 175°, 20/400, and 20/25, respectively, in the right eye, and -3.25 × -5.25 at 179°, 20/200, and 20/25, respectively, in the left eye. In the right and left eyes, the mean corneal thicknesses were 733 and 749 µm, and the maximum epithelial thicknesses were 70 and 68 µm, respectively. Myriads of intraepithelial cysts were observed in the slit-lamp examination. At 30 months after femtosecond laser-assisted laser in situ keratomileusis (femto-LASIK), the manifest refraction and uncorrected and corrected distance visual acuities were respectively 0.00 × -1.25 at 55°, 20/25, and 20/20 in right eye, and 0.00 × -0.50 at 135°, 20/20, and 20/20 in the left eye. In this case of Meesmann dystrophy, myopia was successfully treated with thick flap femto-LASIK without complications or ectasia.

RESUMO A paciente era uma mulher de 26 anos com refração manifesta, acuidade visual para longe não corrigida e corrigida de -7,00 × -4,50 a175°, 20/400 e 20/25 no olho direito e -3,25 × -5,25 a 179°, 20/200 e 20/25 no olho esquerdo. A espessura média da córnea foi de 733 e 749 µm, e a espessura epitelial máxima foi de 70 e 68 µm, respectivamente no olho direito e no esquerdo. Inúmeros cistos intraepiteliais foram observados no exame com lâmpada de fenda. Trinta meses após o femto-LASIK, a refração manifesta, a acuidade visual para longe não corrigida e corrigida eram respectivamente de 0,00 × -1,25 a 55°, 20/25 e 20/20 no olho direito e 0,00 × -0,50 a 135°, 20/20 e 20/20 no olho esquerdo. Neste caso de distrofia de Meesmann, a miopia foi tratada com sucesso com femto-LASIK de retalho espesso sem complicações ou ectasia.

Avaliação do conhecimento sobre cirurgia refrativa por meio de questionário eletrônico / Evaluation of knowledge in refractive surgery using an on-line questionnaire

RESUMO Objetivo: Desenvolver e aplicar um questionário eletrônico para avaliação do conhecimento em cirurgia refrativa na população analisada. Métodos: Foi aplicado um questionário eletrônico a uma população composta de 840 participantes voluntários maiores de 18 anos. Resultados: A média da idade dos participantes foi 37,85 anos, sendo 60,1% do feminino. Dentre os participantes, 20,95% reportaram ter sido submetidos a alguma cirurgia ocular prévia, sendo 73,86% com objetivo refrativo. Entre estes, 73,08% mostraram-se satisfeitos/muito satisfeitos com o resultado. O critério mais importante na escolha de um cirurgião refrativo foi a indicação por um conhecido que realizara a cirurgia (43,81%). Destaca-se que os participantes submetidos à cirurgia refrativa discordaram que "a cirurgia é um procedimento simples e isento de riscos" mais do que as demais pessoas (p=0,0045) e também que "o objetivo principal da cirurgia é 'zerar' o grau" (p=0,0252). Conclusão: Nota-se a necessidade de melhorar o conhecimento pré-operatório da população sobre cirurgia refrativa e também de educação continuada para os oftalmologistas. Este estudo fomenta o desenvolvimento de novas ferramentas de educação com informações claras e de fácil acesso, que tenham caráter informativo, e não de convencimento.

ABSTRACT Objective: The purpose of this study was to develop and apply an online questionnaire to assess knowledge in Refractive Surgery in the analyzed population. Methods: An online questionnaire was applied to a population composed of 840 volunteer participants over 18 years of age. Results: The mean age of population was 37.85 years, of whom 60.1% were female. 20.95% of the participants reported having undergone previous eye surgery, 73.86% of which had a refractive objective. Among these, 73.08% were satisfied / very satisfied with the result. The most important criterion when choosing a refractive surgeon was the indication by a friend who underwent the procedure (43.81%). It is noteworthy that the participants who underwent refractive surgery disagreed more than the other people that "the surgery is a simple and risk-free procedure" (p = 0.0045) and that "the main objective of the surgery is to "zero" the diopter" (p = 0.0252). Conclusion: It is essential to improve population's preoperative knowledge about Refractive Surgery, as well as continuing education for ophthalmologists. Therefore, this study encourages the development of new education tools with clear and easily accessible information, which should be informative, and not convincing.

Unexpectedly high corneal flap thickness and ectasia after mechanical LASIK / Espessura inesperadamente alta do flap corneano e ectasia após LASIK mecânico

ABSTRACT LASIK is a refractive surgical procedure in which a corneal flap is created to expose the corneal stromal bed. Preoperative estimation of corneal flap thickness is necessary to calculate the percentage tissue altered in LASIK, an important quantitative risk factor for ectasia. The objective of this study was to assess flap thickness and calculate percentage tissue altered to check if unexpectedly thicker flaps and higher percentage tissue altered could pose as risk factors of ectasia. Four subjects (eight eyes) were submitted to mechanical LASIK in 2009 and 2010. Pre and postoperative clinical and tomographic data were reviewed. Mean preoperative estimated percentage tissue altered was 39.18±1.31%, which was borderline for increased ectasia risk when considering the limit of 40%. However, when considering the postoperatively measured flap thickness, the actual mean percentage tissue altered turned out to be 45.17 ± 4.13%, which was significantly higher than predicted preoperatively (p=0.002). Unexpectedly higher postoperative percentage tissue altered may be responsible for corneal ectasia after mechanical LASIK.

RESUMO A LASIK é um procedimento cirúrgico refrativo, no qual um retalho corneano é criado para expor o leito estromal corneano. A estimativa pré-operatória da espessura do retalho corneano é necessária para calcular o percentual de tecido alterado no LASIK, um importante fator de risco quantitativo para ectasia. O objetivo deste estudo foi avaliar a espessura do retalho e calcular o percentual de tecido alterado para verificar se retalhos inesperadamente mais espessos e percentuais de tecido alterado mais altos poderiam representar fatores de risco de ectasia. Quatro indivíduos (oito olhos) foram submetidos à LASIK mecânica em 2009 e 2010. Dados clínicos e tomográficos pré e pós-operatórios foram revisados. A média de percentual de tecido alterado pré-operatória estimada foi de 39,18±1,31%, limítrofe para risco aumentado de ectasia quando considerado o limite de 40%. No entanto, ao considerar a espessura do retalho medida no pós-operatório, o percentual de tecido alterado médio real foi de 45,17±4,13%, ou seja, significativamente maior do que o previsto no pré-operatório (p=0,002). O percentual de tecido alterado pós-operatóriao inesperadamente mais alto pode ser responsável pela ectasia da córnea após LASIK mecânico.

Comparison of surgically induced astigmatic changes after cataract surgery in post-Laser in situ keratomileusis corneas versus virgin eyes / Comparação de alterações astigmáticas induzidas cirurgicamente após cirurgia de catarata em córneas ceratomileusis in situ pós-Laser versus olhos virgens

ABSTRACT Purpose: Postoperative refraction in modern mi­croincision cataract surgery gained extra importance in patients with the previous laser-assisted in situ keratomileusis (LASIK) surgery. The surgically induced astigmatic changes in those eyes may differ not only in magnitude but also in direction compared to virgin corneas. This study aimed to compare the surgically induced astigmatic changes after microscopic cataract surgery between post-LASIK corneas and virgin eyes. Methods: Cases that underwent microincision cataract surgery in eyes with and without previous LASIK surgery were reviewed. The demographics, the axial length at cataract surgery, the central corneal thickness, spheric and cylindric values, keratometry readings, and postoperative posterior corneal astigmatism were retrospectively evaluated. A modified Alpins method was used for astigmatic vector analysis, and baseline astigmatism, surgically induced astigmatism, difference vector, flattening effect, and torque were assessed. Results: A total of 42 eyes from 24 subjects was evaluated. Group I consisted of 14 eyes with the previous LASIK, and Group II included 28 eyes without any refractive surgery. Preoperative mean central corneal thickness in Group I was significantly thinner (p=0.012). There was no significant difference in baseline astigmatism between the groups regarding magnitude and power vectors. After microincision cataract surgery, there were no significant differences in mean spheric and cylindric values and mean keratometry readings (all p>0.05). However, surgically induced astigmatism and difference vector were significantly higher on J45 vector component in post-LASIK eyes and microincision cataract surgery steepening effect on post-LASIK corneas was significantly higher than those in virgin eyes (p=0.001, p=0.002 and p=0.018, respectively). Conclusions: Cataract surgery has steepened the corneas in both groups with a significantly higher steepening effect in post-LASIK eyes. Certainly, corneal topography cataract surgery is particularly helpful to provide more precise surgically induced astigmatism interpretations.

RESUMO Objetivo: A refração pós-operatória na cirurgia mo­derna de catarata por microincisão ganha ainda mais importância em pacientes com cirurgia prévia de ceratomileuse in situ assistida por laser (LASIK). As alterações astigmáticas induzidas cirurgicamente nesses olhos podem diferir não apenas em magnitude, mas também em direção em comparação com córneas virgens. O objetivo deste estudo foi comparar as alterações astigmáticas induzidas cirurgicamente após cirurgia de catarata por microincisão entre córneas pós-LASIK e olhos virgens. Métodos: Foi revisada uma série de casos de cirurgia de catarata por microincisão em olhos com e sem cirurgia LASIK anterior. Os dados demográficos, o comprimento axial no momento da cirurgia de catarata, a espessura central da córnea, os valores esféricos e cilíndricos, as leituras da ceratometria e o astigmatismo corneano posterior pós-operatório foram avaliados retrospectivamente. O método Alpins modificado foi usado para análise vetorial astigmática e foram avaliados o astigmatismo basal, o astigmatismo induzido cirurgicamente, o vetor de diferença, o efeito de achatamento e o torque. Resultados: Ao todo, 42 olhos de 24 indivíduos foram avaliados. O Grupo I consistiu em 14 olhos com LASIK prévio; o Grupo II incluiu 28 olhos sem qualquer cirurgia refrativa. A média da espessura corneana central pré-operatória no Grupo I foi significativamente mais fina (p=0,012). Não houve diferença significativa no astigmatismo basal entre os grupos em termos de magnitude e vetores de potência. Após a cirurgia de catarata por microincisão, não houve diferenças significativas nos valores médios esféricos, cilíndricos e leituras médias de ceratometria (todos com p>0,05). No entanto, o astigmatismo induzido cirurgicamente e o vetor de diferença foram significativamente maiores no componente do vetor J45 em olhos pós-LASIK, e o efeito de aumento da inclinação pela cirurgia de catarata por microincisão nas córneas pós-LASIK foi significativo em comparação com olhos virgens (p=0,001, p=0,002 e p=0,018, respectivamente). Conclusões: A cirurgia de catarata aumentou a inclinação das córneas em ambos os grupos, sendo esse aumento significativamente maior nos olhos pós-LASIK. Certamente, a topografia da córnea antes da cirurgia de catarata é particularmente útil para fornecer interpretações mais precisas do astigmatismo induzido cirurgicamente.

Ablação personalizada guiada por frente de onda após complicação na dissecção lamelar de FemtoLasik / Personalized wavefront-guided ablation after complication in FemtoLasik lamella dissection

RESUMO O FemtoLasik é uma das técnicas mais empregadas em cirurgia refrativa, por seus bons resultados refracionais, sua previsibilidade, sua reprodutibilidade e sua segurança. Tem alto grau de satisfação, com rápida recuperação visual. Apesar de as taxas de complicações do FemtoLasik serem pequenas, intercorrências podem existir. O objetivo deste trabalho foi relatar um caso de uma complicação na dissecção da lamela por Lasik com laser de femtossegundo com consequente rasgadura da lamela, sendo aplicado Excimer Laser com mitomicina C 0,02%. O retratamento foi realizado com ablação de superfície (ceratectomia fotorrefrativa) guiada por frente de onda, evoluindo com boa qualidade visual final.

ABSTRACT Femtolasik is one of the most used techniques in refractive surgery due to good refractive results, predictability, reproducibility, and safety, achieving excellent results and a high degree of satisfaction. Although the complication rates are small, it is worth noting that there may be intercurrences. The objective of this work is to report a case of complication in the dissection of the lamella of laser in situ keratomileusis (Lasik) with Femtosecond laser, and subsequent lamella tear. Excimer Laser was applied with mitomycin 0.02% and re-approached with wavefront guided surgery, evolving with good final visual quality.

Reassessment of the Clinical Significance of the Demarcation Line in the Corneal Stroma in Crosslinking

To consider the clinical significance and features of the formation of a demarcation line in the corneal stroma with various methods of corneal crosslinking.Materials and Methods: Literature data on the evaluation of the effectiveness of various methods of crosslinking by the demarcation line in the corneal stroma were analyzed. The formation of a demarcation line during prophylactic and therapeutic excimer laser crosslinking was studied after various photorefractive operations, keratoconus and other pathologies of the cornea (168 operations).Results: With various methods of crosslinking, including prophylactic and therapeutic excimer laser corneal crosslinking, the depth of the demarcation line in the stroma varied from 1/3 to 2/3 of the corneal thickness. It was noted that the saturation of the corneal stroma with a 0.25% solution of riboflavin is accompanied by a large increasing effect of the optical density in the stroma above the demarcation line at a shallower depth of its occurrence. The severity of the aseptic inflammatory reaction after corneal crosslinking affected the optical density, shape, intensity, and depth of the demarcation line in the stroma. In some cases, the formation of a demarcation line in the stroma was noted when the stroma was saturated with riboflavin immediately after refractive keratoablation without additional UV irradiation. The demarcation line in the stroma was revealed during inflammatory processes in the corneal stroma without the participation of riboflavin and its activation by UV radiation. The study showed that the assessment of corneal crosslinking by the depth of the demarcation line is not an indicator of the photochemical process and the number of crosslinks formed in the corneal stroma.Conclusion: Based on the severity, shape and depth of the demarcation line, it is not possible to judge the density of crosslinks in the corneal stroma, which predetermine its strength properties after one or another method of corneal crosslinking.

Aterectomia coronária com Excimer Laser como tratamento adjuvante da subexpansão grave do stent com calcificação volumosa / Excimer Laser coronary atherectomy as adjunctive treatment of severe stent underexpansion with bulky calcification

A aterectomia coronária com Excimer Laser melhorou significativamente nos últimos anos, utilizando emissão ultravioleta de alta energia e comprimento de onda curto, com menor penetração e menor emissão de calor, resultando em menos danos aos tecidos e menos complicações. Descrevemos o caso de um paciente do sexo masculino, 66 anos, ex-tabagista, hipertenso, diabético, dislipidêmico. Foi submetido a múltiplas intervenções coronárias percutâneas na artéria descendente anterior com stents não farmacológicos e farmacológicos. Na última intervenção coronária percutânea, o stent foi subexpandido, e o paciente apresentou trombose aguda do stent e reestenose recorrente do stent. Foram realizadas novas intervenções coronárias percutâneas com aterectomia coronária com Excimer Laser adjuvante, devido à angina refratária, com uso de carga progressiva e injeção de soro fisiológico, seguidas de posterior insuflação de balão de alta pressão e implante de stent farmacológico, com resultado excelente. No acompanhamento de 8 meses, o paciente se manteve assintomático.

Excimer Laser coronary atherectomy has improved significantly in recent years, emitting high-energy ultraviolet and short wavelength with less penetration and heat emission, ultimately leading to less tissue damage and fewer complications. We described a case of a 66-year-old male patient, former smoker and suffering from hypertension, diabetes mellitus, and dyslipidemia. He underwent multiple percutaneous coronary interventions in the left anterior descending artery with bare metal and drug-eluting stents. In the last percutaneous coronary intervention, the stent was underexpanded and the patient presented acute stent thrombosis and recurrent stent restenosis. New percutaneous coronary interventions with adjunctive Excimer Laser coronary atherectomy were undertaken due to refractory angina, using progressive load and saline injection, followed by subsequent high-pressure balloon inflation and drug-eluting stent implantation with an excellent result. At 8-month follow-up, the patient was asymptomatic.

Clinical effects of nanoneedle injection of compound betamethasone combined with 308 nm excimer laser on patients with stable vitiligo / 中华医学美学美容杂志

Objective:To evaluate the efficacy for nanoscale microneedle injection of compound betamethasone combined with 308 nm excimer laser in the treatment of stable vitiligo patients.Methods:A total of 80 patients with stable vitiligo were enrolled in Guangzhou Dermatology Hospital from May 2018 to May 2020. There were 40 patients (21 males and 19 females) in control group, aged 17-65 (32.4±1.7) years, and 40 patients (20 males and 20 females) in observation group, aged 18-67 (28.7±1.8) years. The control group was treated with compound betamethasone injection packet combined with 308 nm excimer laser. The observation group was treated with nanoneedle injection of compound betamethasone combined with 308 nm excimer laser. We compared the clinical efficacy and incidence of adverse reactions between the two groups.Results:Comparison of clinical efficacy showed that after 3 months of treatment, the total effective rates of the observation group and the control group were 80.00% and 67.50%, respectively, with significant difference (χ 2=4.560, P<0.05). After 3 months of treatment, the white spot area of the control group was (9.89±1.65) cm 2, which was significantly higher than that of the observation group (7.83±1.78) cm 2 ( t=5.370, P<0.05). Conclusions:The nanoneedle injection of compound betamethasone combined with 308 nm excimer laser in the treatment of stable vitiligo is effective and safe.

Clinical analysis of excimer laser atherectomy in the treatment of diabetic foot with infrapopliteal arteriopathy / 中国医师杂志

Objective:To explore the clinical efficacy of excimer laser atherectomy (ELA) in the treatment of diabetic foot with infrapopliteal arteriopathy.Methods:The clinical data of 36 patients (40 limbs) with diabetic foot complicated with inferior knee artery disease treated by ELA in Xinjiang Uygur Autonomous Region People′s Hospital from December 2019 to May 2021 were analyzed retrospectively. The success rate of ELA in the treatment of diabetic inferior genicular artery disease, ankle-brachial index (ABI), limb salvage rate and Visual Analogue Scale (VAS) score at 3 days and 3 and 6 months after operation was observed.Results:All the 36 patients were operated successfully, including 2 cases of flow-limiting dissection, 2 cases of arterial embolism and 1 case of hematoma at the puncture point. The ABI of patients 3, 6 months after operation was significantly higher than that before operation (all P<0.05), and the VAS score 3, 6 months after operation was significantly lower than that before operation (all P<0.05). The rate of limb (toe) salvage were 92.5%(37/40), 82.5%(33/40) at 3 d, 3 months and 77.5%(31/40) at 6 months after operation. Conclusions:ELA is safe and effective in the treatment of diabetic foot infrapopliteal arteriopathy, and the recent efficacy is fair.

Distal embolic filter protection during debulking treatment of peripheral artery disease / 中华普通外科杂志

Objective:To discuss the strategies of distal embolic filter protection(DEFP) during excimer laser ablation (ELA) or percutaneous mechanical thrombectomy (PMT) in treatment of peripheral artery disease.Methods:Clinical data of 29 patients undergoing ELA or PMT under the DEFP from Oct 2019 to Aug 2021 were retrospectively collected to analyze the strategies of DEFP and high-risk factors of capturing clinically significant macrodebris.Results:There were 21 males and 8 females, aged (70.3±11.0) years with 32 lesions (29 limbs) including 5 in-stent restenosis (ISR), 10 thrombosis and 17 chronic total occlusion (CTO). The technical success rate of DEFP device release and recovery was 100%. The overall debris capture rate was 77.3% and the macrodebris capture rate was 36.4%. Even with DEFP the distal embolization (DE) incidence was 3.4%. When ELA for CTO with severe calcification or long-segment ISR lesions, the capture rate of macrodebris was as high as 60.0%, and the former was significantly higher than ELA for CTO without high calcification lesions ( P<0.05). Conclusion:ELA or PMT under the DEFP in treatment of peripheral artery disease appears to be of great significance in preventing DE.

Efficacy and safety of 308-nm SQ light-emitting diode light and 308-nm excimer light in the treatment of facial vitiligo: a retrospective study / 中华皮肤科杂志

Objective:To compare efficacy and safety of 308-nm SQ light-emitting diode (LED) light versus 308-nm excimer light in the treatment of facial vitiligo.Methods:Patients with stable facial vitiligo were retrospectively collected from Department of Physical Therapy, Hospital of Dermatology, Chinese Academy of Medical Sciences from June 2018 to June 2020, who received treatment with 308-nm SQ LED light (LED group) or 308-nm excimer light (excimer light group). The treatment was performed once or twice a week, and patients who had received more than 8 sessions of treatment were included in the analysis of efficacy and safety. Statistical analysis was carried out by using chi-square test.Results:Totally, 68 patients with 90 lesions were enrolled into the LED group, including 36 males and 32 females, aged 25.01 ± 13.37 years; 20 patients with 28 lesions were enrolled into the excimer light group, including 13 males and 7 females, aged 27.15 ± 14.30 years. After 8 and 16 sessions of treatment, there was no significant difference in the response rate between the LED group (23.33%, 46.67%, respectively) and excimer light group (14.29%, 46.43%, χ2 = 1.05, < 0.001, respectively, both P > 0.05). During the treatment, 36 (52.94%) patients in the LED group developed persistent erythema, 17 (85%) in the excimer light group developed persistent erythema or blisters. The incidence of adverse reactions was significantly lower in the LED group than in the excimer light group ( χ2 = 16.43, P < 0.001) . Conclusion:Compared with the 308-nm excimer light, the 308-nm SQ LED light showed similar effect but higher safety for the treatment of facial vitiligo.

Comparison of clinical outcome between femtosecond laser-assisted LASIK and SMILE for myopic astigmatism by vector analysis / 中华实验眼科杂志

Objective:To compare the accuracy and stability between corneal topography-guided femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) for myopic astigmatism by vector analysis.Methods:A non-randomized controlled clinical trial was performed.One hundred and twenty patients (214 eyes) with myopic astigmatism who underwent the FS-LASIK or SMILE in Henan Eye Hospital from January 2020 to July 2020 were enrolled.The patients were divided into FS-LASIK group (58 cases, 105 eyes) and SMILE group (62 cases, 109 eyes) according to different surgeries.The visual acuity, refraction, intraocular pressure and corneal topography were examined before and 1 week, 1 month and 3 months after operation.The results of vector analysis between the two groups were compared, including target induced astigmatism vector (TIA), surgically induced astigmatism vector (SIA), magnitude of error (ME), angle of error (|AE|), difference vector (|DV|), correction index (CI), and index of success (IOS) 3 months after operation.This study protocol adhered to the Declaration of Helsinki and was approved by an Ethics Committee of Henan Eye Hospital (No.HNEECKY-2020[25]). Written informed consent was obtained from each patient before operation.Results:Three months after surgery, no astigmatism was found in 11 eyes (10.5%), and with the rule (WTR) astigmatism was in 23 eyes (21.9%), and against the rule (ATR) and oblique astigmatism were in 71 eyes (67.6%) in FS-LASIK group.In SMILE group, no astigmatism was detected in 35 eyes (32.1%), and WTR astigmatism was in 58 eyes (53.2%), and ATR and oblique astigmatism were in 16 eyes (14.7%), showing a statistically significant difference between them ( χ2 =48.20, P<0.05). The postoperative SIA, |AE|, |DV|, CI and IOS values in the SMILE group were lower than those in the FS-LASIK group, showing statistically significant differences between them (all at P<0.05). The ME was -0.20 (-0.37, 0.00)D in FS-LASIK group and 0.20 (0.00, 0.25)D in SMILE group.Within 3 months after operation, there was no significant difference in ME among different time points in the FS-LASIK group (all at P>0.05) and in spherical equivalent (SE) among different time points in the SMILE group (all at P>0.05). There was significant difference in the results of vector analysis among different time points in the two groups (all at P<0.05). Conclusions:Both FS-LASIK and SMILE are effective in the correction of myopic astigmatism.Astigmatism is slightly overcorrected by FS-LASIK and slightly undercorrected by SMILE.The axial error is smaller and the SE is more stable after SMILE within 3 months postoperatively.

Observation and study on uncorrected distance visual acuity and ocular adjustment function before and after excimer laser photorefractive keratectomy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To analyze the changes of uncorrected distance visual acuity(UCDVA)and ocular accommodation before and after excimer laser photorefractive keratectomy(PRK).METHODS: A retrospective study. There were 120 patients(240 eyes)who underwent PRK surgery in our center from December 2017 to December 2019 divided into two groups according to the diopter of spherical equivalent(SE): 70 cases with SE≤-6.00D in the mild to moderate myopia group and 50 cases with -6.00D&#x003C;SE≤-9.00D in the high myopia group which were observed and analyzed. The UCDVA(LogMAR), monocular accommodative amplitude(AMP), negative relative accommodation(NRA), positive relative accommodation(PRA)and monocular accommodative flipper(AF)were measured before and after operation at 1wk, 1 and 3mo. RESULTS: In the group of low-moderate myopia and high-myopia group, the UCDVA at 1wk, 1 and 3 mo after operation was significantly increased compared with those before operation(all P&#x003C;0.01). The increase of UCDVA of low to moderate myopia group was better than that in the high myopia group at 3mo after operation(P&#x003C;0.05). Monocular AMP in the both groups firstly decreased and increased afterwards, and there was a significant decrease than that before operation at 1wk and 1mo after operation(P&#x003C;0.01). AMP reached and was better than that before operation at 3mo after operation(P&#x003C;0.01). The increase of low to moderate myopia group was both higher and faster than that of high myopia group. Compared with PRA before operation, the patients of low to moderate myopia group decreased at 1wk after operation(P&#x003C;0.01), postoperative levels at 1mo recovered to preoperative level(P&#x003E;0.05)and postoperative at 3mo was superior to preoperative operation(P&#x003C;0.05); High myopia group did not change significantly at 1wk and 1mo after operation compared with preoperative operation(P&#x003E;0.05), and increased at 3mo after operation compared with preoperative level(P&#x003C;0.01). For low to moderate myopia group, there was no significant difference in preoperative and postoperative NRA, and at 1wk after operation, NRA of high myopia group temporarily increased compared with preoperative operation(P&#x003C;0.01). At 1mo after operation, it returned to the preoperative level(P&#x003E;0.05), and significantly increased at 3mo after operation compared with preoperative operation(P&#x003C;0.01). Monocular AF for both groups significantly decreased at 1wk after operation compared with preoperative operation, recovered at 1mo after operation and was significantly better at 3mo after operation(all P&#x003C;0.01); The low-to-moderate group increased more than the high-myopia group.CONCLUSION: PRK has a good correction effect for myopia below -9.00D, and people in low to moderate myopia have a better postoperative UCDVA correction effect than those in high myopia. The eye accommodation will be abnormal in a short period after operation. The recovery and improvement time of accommodative function in low-moderate myopia group are shorter than that in high myopia group, but both groups can recover and improve at 3mo after operation compared with the preoperative levels.

Observation of corneal wavefront-guided FS-LASIK in the treatment of myopia with different degrees of astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the postoperative efficacy of corneal wavefront-guided femtosecond laser-assisted excimer in situ keratomileusis(FS-LASIK)in the treatment of myopia patients with different degrees of astigmatism and the changes of corneal higher order aberration.METHODS: A total of 133 patients(265 eyes)with myopia and astigmatism were enrolled in this retrospective study. All of them underwent corneal wavefront-guided FS-LASIK surgery for the first time in Aier Eye Hospital(Kunming)from April to October 2020. The patients were divided into three groups according to the different astigmatism: Low astigmatism group: astigmatism ≤1.0D, 62 cases(124 eyes), medium astigmatism group: a total of 54 cases(107 eyes)with astigmatism was 1.25-2.0D, high astigmatism group: a total of 17 cases(34 eyes)with astigmatism ≥2.25D. Visual acuity and refraction were recorded before surgery and 3mo after the surgery and the cornea of the patients was measured by Pentacam three-dimensional corneal topography. Record total higher order aberrations(root mean square), spherical aberration, horizontal coma, vertical coma, horizontal clover and oblique clover in the 6mm diameter range of the cornea. The postoperative effects of the three groups of patients were observed and the changes of corneal high order aberration before and after surgery were compared. RESULTS: The validity index of visual acuity in the three groups of patients was all greater than 1.1 and the residual diopter was all within ±0.30D. The residual diopter in the low astigmatism group was the least than that of the other two groups(P&#x003C;0.05). At 3mo after surgery, the corneal total higher order aberration, spherical aberration and vertical coma of the three groups were all increased compared with those before surgery(P&#x003C;0.05). The spherical aberration increase in the high astigmatism group was less than that in the other two groups(P&#x003C;0.05).CONCLUSION: Corneal wavefront-guided FS-LASIK surgery is safe and effective in the treatment of myopia with different degrees of astigmatism, and the effect is also accurate for patients with high astigmatism. The degree of of preoperative astigmatism is not responsible for increased corneal higher order aberration after the surgery.