Uso clínico de MS-39: topógrafo para el estudio del segmento anterior / Clinical use of MS-39: a topograph for the study of the anterior segment

El ojo humano es un instrumento óptico simple, pero extremadamente robusto. Los sistemas de imágenes para el diagnóstico y evaluación del segmento anterior del ojo constituyen una herramienta fundamental para el oftalmólogo. Hasta hace poco, el uso de estas técnicas proporcionaba fundamentalmente información cualitativa sobre ciertas enfermedades; sin embargo, el desarrollo de nuevas técnicas de cuantificación abre una nueva Era de evaluación y tratamiento basado en imagen. La tomografía de coherencia óptica de segmento anterior se ha convertido en una herramienta crucial en la Oftalmología. El MS-39 es un topógrafo que usa el dominio espectral y la topografía con disco de Plácido para obtener mediciones del segmento anterior del ojo. Brinda información sobre paquimetría, elevación, curvatura y poder dióptrico de ambas caras de la córnea. Además, permite realizar mapas epiteliales y biometría del cristalino. La alta repetibilidad de esta tecnología justifica su uso en la práctica clínica. De ahí la motivación para realizar una búsqueda de diversos artículos publicados, con el objetivo de describir las características y la utilidad del MS-39 para el estudio del segmento anterior del ojo. Se utilizó la plataforma Infomed, específicamente la Biblioteca Virtual de Salud, con todos sus buscadores(AU)

The human eye is a simple but extremely robust optical tool. Imaging systems for the diagnosis and evaluation of the anterior segment of the eye are a fundamental tool for ophthalmologists. Until recently, use of these techniques mainly provided qualitative information about certain diseases; however, the current development of quantification techniques has paved the way for a new era in image-based evaluation and treatment. Optical coherence tomography of the anterior segment has gained crucial importance in ophthalmology. MS-39 is a topograph that uses the spectral domain and Placido disc topography to obtain measurements of the anterior segment of the eye. This tool provides information about the pachymetry, elevation, curvature and dioptric power of both sides of the cornea. It also permits the development of epithelial maps and crystalline lens biometry. The great repeatability of this technology justifies its use in clinical practice. Hence the motivation to conduct a search for a variety of published papers, with the purpose of describing the characteristics and usefulness of the MS-39 for the study of the anterior segment of the eye. Use was made of the Infomed platform, particularly the Virtual Health Library with all its search engines(AU)

Effects of two different contact lenses on ocular physiological parameters and tear function tests / Efeitos de duas lentes de contacto diferentes nos parâmetros fisiológicos oculares e nos testes de função lacrimal

Abstract Objective: To investigate the effects of two types of contact lenses made of two different types of silicone hydrogel material on ocular physiological parameters and tear function tests. Methods: The contact lenses with the appropriate diopters were supplied to the volunteering patients. The patients were evaluated before wearing the contact lenses (visit0:V0), at the first month(visit1:V1) and at the thirth month(visit2:V2) following their wear. At all visits a detailed biomicroscopic examination was done, ocular physiological variables were collected, the tear function tests were performed and the tear meniscus area (TMA) was visualized and measured with anterior segment optical coherence tomography (AS-OCT). Results: The results of Schirmer 1 test were 12.07 ± 1.51 [9-16] mm for the right eyes (samfilcon A group) and 12.09 ± 1.5 [9-16] mm for the left eyes (senofilcon A group) at V0. (p=0.950) At V2, the mean Schirmer 1 test results were 11.92±1.34 [9-15] mm in the samfilcon A group and 12.2±1.41 [9-16] mm in the senofilcon A group (p=0.239). The mean TMA dimensions in the AS-OCT images were 338.42±47.1 [241-401] microns in the samfilcon A group and 338.42±47.1 [241-401]microns in the senofilcon A group at V0. (p>0.05). At V2, the mean TMA dimensions were 337.2±45.53 [241-402] microns in thesamfilcon A group and 340.31±48.22 [240-411] microns in the senofilcon A group (p=0.728). Conclusions: Our study has demonstrated that contact lenses containing samfilcon A and senofilcon A silicone hydrogel material do not cause meaningful ocular surface problems.

Resumo Objetivo: Investigar os efeitos de dois tipos de lentes de contacto feitas de dois tipos diferentes de material de hidrogel de silicone nos parâmetros fisiológicos oculares e testes de função lacrimal. Métodos: As lentes de contacto com as dioptrias apropriadas foram fornecidas aos pacientes voluntários. Os pacientes foram avaliados antes do uso das lentes de contacto (visita0: V0), no primeiro mês (visita1: V1) e no terceiro mês (visita2: V2), após o uso destas. Em todas as visitas, foi realizado um exame biomicroscópico detalhado, as variáveis fisiológicas oculares foram recolhidas, os testes de função lacrimal foram realizados e a área do menisco lacrimal (TMA) foi visualizada e medida com tomografia de coerência óptica do segmento anterior (AS-OCT). Resultados: Os resultados do teste de Schirmer 1 foram 12,07 ± 1,51 [9-16] mm para os olhos direitos (grupo samfilcon A) e 12,09 ± 1,5 [9-16] mm para os olhos esquerdos (grupo senofilcon A) em V0. (p = 0,950) Em V2, os resultados médios do teste de Schirmer 1 foram 11,92 ± 1,34 [9-15] mm no grupo samfilcon A e 12,2 ± 1,41 [9-16] mm no grupo senofilcon A (p = 0,239). As dimensões médias do TMA nas imagens AS-OCT foram 338,42 ± 47,1 [241-401] mícrons no grupo samfilcon A e 338,42 ± 47,1 [241-401] mícrons no grupo senofilcon A em V0. (p> 0,05).> Em V2, as dimensões médias do TMA foram 337,2 ± 45,53 [241-402] mícrons no grupo samfilcon A e 340,31 ± 48,22 [240-411] mícrons no grupo senofilcon A (p = 0,728). Conclusões: O nosso estudo demonstrou que as lentes de contacto que contêm material de hidrogel de silicone de samfilcon A e senofilcon A não causam problemas significativos na superfície ocular.

Effect of contact lenses on ocular biometric measurements based on swept-source optical coherence tomography / Efeito de lentes de contato em um biômetro ocular baseado na tomografia de coerência óptica de varredura

ABSTRACT Purpose: To determine the reliability of swept- source optical coherence tomography in cases in which soft contact lenses cannot be removed when acquiring biometric measurements. Methods: Eight subjects were included and only one eye per participant was analyzed. Each eye was measured six times by swept-source optical coherence tomography with the IOLMaster 700 instrument (Carl Zeiss Meditec, Jena, Germany). Axial length, central corneal thickness, anterior chamber depth, lens thickness, and keratometric measurements were evaluated for the naked eye and while wearing soft contact lenses of three different powers (-1.5, -3.0, and +2.0 D). Results: There were statistically significant changes in axial length, central corneal thickness, anterior chamber depth, and keratometric measurements with soft contact lenses as compared to the naked eye (p<0.001). However, there were no significant differences in lens thickness outcomes between the naked eye and while wearing the three soft contact lenses (p>0.5). The changes in axial length, central corneal thickness, and anterior chamber depth were lens-specific and dependent on the thickness of the lens used. Conclusions: Sept-source optical coherence tomography based lens thickness measurements while wearing soft contact lenses are comparable to those of the naked eye. However, the thickness and the optical design of the soft contact lens may lead to significant differences in the axial lengh, central corneal thickness, anterior chamber deph, and keratometric measurements.

RESUMO Objetivo: Determinar a confiabilidade da tomografia de coerência óptica de varredura em casos especiais em que lentes de contato gelatinosas não podem ser removidas ao realizar medições biométricas. Métodos: Oito indivíduos foram incluídos e apenas um olho por participante foi analisado. Cada olho foi medido seis vezes por tomografia de coerência óptica de varredura com o instrumento IOLMaster 700 (Carl Zeiss Meditec, Jena, Alemanha). O comprimento axial, a espessura central da córnea, a profundidade da câmara anterior, a espessura da lente e as medidas ceratométricas foram avaliados a olho nu e enquanto usavam lentes de contato gelatinosas de três diferentes potências (-1,5, -3,0 e +2,0 D). Resultados: Houve alterações significativas no comprimento axial, espessura central da córnea, profundidade da câmara anterior e medidas ceratométricas com as lentes de contato gelatinosas em comparação com as a olho nu (p<0,001). No entanto, não houve diferenças significativas nos resultados de espessura do cristalino entre o olho nu e enquanto usava as três lentes de contato gelatinosas (p>0,5). As alterações de comprimento axial, espessura central da córnea e profundidade da câmara anterior foram específicas da lente e dependentes da espessura da lente usada. Conclusões: As medições da espessura da lente baseadas na tomografia de coerência óptica da Sept-source, enquanto usam lentes de lentes de contato gelatinosas, são comparáveis às do olho nu. Entretanto, a es pessura e o desenho óptico da lente de contato gelatinosa podem levar a diferenças significativas no comprimento axial, na espessura central da córnea, na profundidade da câmara anterior e nas medidas ceratométricas.

Assessment of visual acuity improvement in patients with AMD referred to the low vision department / Avaliação da melhora da acuidade visual em pacientes com DMRI encaminhados ao setor de visão subnormal

Abstract Purpose: To evaluate the vision improvement through the use of visual aids of patients with Age-Related Macular Degeneration (AMD) those were examined in the low vision department. Methods: A retrospective study was conducted by reviewing medical records of 61 patients with AMD who were referred to the Low Vision Department from January 2012 to December 2014. The data collected included age, sex, diagnosis of the type of AMD and previous use of vascular endothelium growth factor inhibitor or antioxidants. In addition, far acuity, with and without optical aid, was indicated as well as which aid was prescribed. Results: In this study with 61 patients, 54.1% were male and 45.9% female. The most prevalent age group was 71-80 years old (44.3%) and most of the patients had the dry form of AMD (70.5%). With the use of visual aids, 73.8% of the patients improved visual acuity for far vision. The most prescribed optical aid was the Galileu 2.8x telescope (50.8%). Conclusion: Patients with visual impairment and AMD can benefit significantly from the visual aids if they are properly prescribed and fitted. Most patients in the study were fitted with at least one of the indicated visual aids, resulting in a significant improvement in far acuity.

Resumo Objetivo: Avaliar a melhora da visão através de auxílios visuais em pacientes portadores de Degeneração Macular Relacionada a Idade (DMRI) encaminhados ao serviço de visão subnormal. Métodos: Foi realizado um estudo retrospectivo, através da revisão 61 prontuários de pacientes com diagnóstico de DMRI que foram encaminhados ao departamento de Visão Subnormal (VSN), no período de janeiro 2012 a dezembro de 2014. Foram coletados dados sobre idade, sexo, diagnóstico do tipo de DMRI e uso prévio de inibidor do fator de crescimento do endotélio vascular (anti-VEGF) ou antioxidante. Além disso, outras informações foram colhidas como acuidade visual para longe sem auxílio e com auxílio óptico, indicando o(s) auxílio(s) óptico(s) prescrito(s). Resultados: Dos 61 pacientes avaliados, 54,1% eram do sexo masculino e 45,9% do sexo feminino. A faixa etária mais prevalente foi de 71-80 anos (44,3%) e a maioria (70,5%) apresentava a forma seca de DMRI. Com o uso de recursos visuais, 73,8% dos tiveram melhora da acuidade visual para longe. O auxilio óptico mais prescrito foi o telescópio do tipo Galileu 2,8x (50,8%). Conclusão: Pacientes com deficiência visual e DMRI podem se beneficiar significativamente dos recursos visuais se esses forem devidamente indicados e adaptados. A maioria dos pacientes aceitou pelo menos um dos recursos visuais indicados resultando numa melhora importante da acuidade visual de longe.

Análise clínica, terapêutica e dos parâmetros tomográficos de pacientes portadores de ceratocone atendidos na Fundação Hilton Rocha / Clinical analysis therapy and tomographic parameters of patients diagnosed with keratoconus attended at Fundação Hilton Rocha

Resumo Objetivo: Analisar dados clínicos, terapêuticos e parâmetros tomográficos dos pacientes portadores de ceratocone atendidos na Fundação Hilton Rocha. Métodos: É um estudo retrospectivo com amostra aleatória de 150 pacientes submetidos a tomografia de córnea e segmento anterior (Pentacam - Oculus, Wetzlar, Alemanha) na Fundação Hilton Rocha no ano de 2015. Os pacientes foram classificados como portadores ou suspeitos de ceratocone através dos parâmetros: paquimetria, elevação central anterior e posterior, Ambrosio Relational Thinnest (ART), valor de D e ceratometria. Após a seleção foi realizada análise dos prontuários, coletados dados clínicos e terapêuticos dos pacientes. Os dados foram colocados em tabela e analisados. Resultados: Dos pacientes classificados como portadores de ceratocone, 23% tinham 6 parâmetros alterados, e 10% foram classificados com apenas 1 parâmetro alterado. O índice ART foi o que mais se alterou (83%) nos pacientes portadores de ceratocone. Na análise dos dados clínicos e terapêuticos, 76,8% dos pacientes apresentaram acuidade visual melhor ou igual a 20/60, e 19% mencionaram apresentar atopia e, 90% dos pacientes utilizavam como tratamento apenas lentes corretoras (óculos e lente de contato). Conclusão: A utilização de índices tomográficos para o diagnóstico do ceratocone têm aumentado a sensibilidade e a especificidade na triagem de pacientes portadores desta ectasia, possibilitando o diagnóstico de maneira mais precoce e consequentemente maior sucesso terapêutico.

Abstract Objective: Analyze clinical data, therapy and tomographic parameters of patients attended at Fundação Hilton Rocha. Methods: This essay is a retrospective study based on a random sample of 150 patients submitted to cornea tomography and previous segment (Pentacam - Oculus, Wetzlar, Germany) at Fundação Hilton Rocha in the year 2015. The patients were classified as carriers or suspects of keratoconus through the following parameters: pachymetry, anterior and posterior central elevation, Ambrosio Relational Thinnest (ART), value of D and keratometry. After the selection an analysis of the medical records was done, followed by harvest of clinical and therapeutical data of the patients. The data was put on table and then analyzed. Results: From the numbers of the patients diagnosed with carriers of keratoconus, 23% had 6 altered parameters, and 10% were classified with only 1 altered parameter. The ART index was the one that suffered the largest change (83%) on the keratoconus carriers. After analysis of clinical and therapeutical data, 76.8% of patients showed better or more of 20/60 degree of visual acuity, and 19% mentioned signs of atopy, 90% of the patients were using only corrective lenses as treatment (glasses and contact lenses). Conclusion: The use of tomographic indexes for the diagnosis of keratoconus has been increasing the sensibility and specificity of the triage of carriers of this ecstasy, allowing an earlier and better diagnosis of this medical condition.

Anterior segment optical coherence tomography findings in type I Boston keratoprosthesis / Achados de tomografia de coerência óptica do seguimento anterior em ceratoprótese de Boston tipo I

ABSTRACT Purpose: To report the results of high-resolution anterior segment optical coherence tomography of patients implanted with a type 1 Boston keratoprosthesis (KPro). Methods: The retrospective study cohort included 11 eyes of 11 patients (average age, 58.4 years; range, 34-83 years). All subjects underwent anterior segment optical coherence tomography at a single posteoperative time point. The main outcome measures were retro-backplate and retro-optic membrane formation, thinning and gap formation of the corneal carrier graft (melting), and degree of angle closure. Results: Preoperative diagnoses included chemical burn (55%), failed corneal transplant (36%), and Stevens-Johnson syndrome (9%). The mean postoperative follow-up duration was 38.5 (range, 12-72) months. The most frequent findings of anterior segment optical coherence tomography were retroprosthetic membrane formation (63%, 7/11), thinning of the corneal carrier graft (melting; 55%, 6/11), and a narrow or closed angle (91%, 10/11). Other less common findings were epithelial growth over the optic surface and periprosthetic cyst formation. Retroprosthetic membrane formation was observed in all patients with melting (6/11). Conclusions: Detailed postoperative examination and visualization of subtle changes of keratoprosthesis implanted eyes by slit lamp biomicroscopy are often difficult. Anterior segment optical coherence tomography is a useful, noninvasive, and quantitative imaging technique that provides useful information to postoperatively monitor the anatomic stability of an implanted keratoprosthesis.

RESUMO Objetivos: Reportar os resultados das imagens de pacientes com Ceratoprótese de Boston tipo I (KPro) usando tomografia de coerência óptica de alta resolução do seguimento anterior (AS-OCT). Métodos: Nós realizamos um estudo retrospectivo de pacientes submetidos à KPro. Um total de 11 olhos de 11 pacientes foram incluídos. As imagens de AS-OCT foram realizadas em um único tempo de pós-operatório. Os principais resultados incluem formação de membrana retroprostética atrás do prato posterior e atrás do cilindro ótico, afinamento e lacunas na córnea doadora (melt) e graus de ângulo fechado. Resultados: Os diagnósticos pré-operatórios inclui queimadura química (55%), falência pós transplante de córnea (36%) e síndrome de Stevens Johnson (9%). A idade média foi de 58.4 anos (escala, 34-83 anos). A média de tempo de pós-operatório foi de 38.5 meses (escala, 12-72 meses). Os achados mais frequentes de AS-OCT foram: membrana retroprostética, 63% (7/11); afinamento da córnea doadora (melting), 55% (6/11); angulo estreito ou fechado, 91% (10/11). Outros achados menos comuns foram crescimento epitelial sobre a superfície ótica e cistos periprostéticos. Todos os pacientes com melting (6/11) apresentaram membrana retroprostética. Conclusões: O exame pós-operatório e a visualização detalhada das mudanças em olhos com KPro pela lâmpada de fenda pode ser difícil. AS-OCT é uma técnica de imagem útil, não invasiva e quantitativa que permite o monitoramento da estabilidade anatômica no seguimento de KPro implantadas.

In vivo OCT assessment of anterior segment central axial lengths with accommodation / Avaliação por OCT in vivo do comprimentos axiais centrais do segmento anterior

ABSTRACT Purpose: To assess changes in anatomic structures in the anterior eye segment in terms of axial lengths with accommodation via optical coherence tomography. Methods: In this observational study, 25 eyes of 25 healthy adults were examined using the Visante® omni optical coherence tomography system. Central corneal thickness, anterior chamber depth, central lens thickness, and anterior segment length were assessed. The evaluated parameters were obtained with accommodation using different stimulus vergences, namely 0.0, -1.0, -2.0, and -3.0 D. Variation of these parameters was compared among different levels of accommodation. Results: Central corneal thickness was not altered at any stimulus vergence during accommodation (p>0.05). Conversely, anterior chamber depth was significantly reduced (p<0.05), whereas central lens thickness was significantly increased (p<0.05). Anterior segment length also increased with accommodation (p<0.05), indicating backward movement of the posterior pole. Conclusions: There are significant variations in anterior segment lengths that occur with accommodation. Studying these changes will provide useful information regarding the accommodation mechanism that can improve our understanding of this process and facilitate clinical decision-making by practitioners.

RESUMO Objetivo: Avaliar as mudanças das estruturas anatômicas no segmento anterior do olho em termos de comprimentos axiais com acomodação por meio da tomografia de coerência óptica. Métodos: Neste estudo observacional, foram incluídos 25 olhos de vinte e cinco adultos saudáveis e medidos com o sistema Visante® omni tomografia de coerência óptica. A espessura corneana central, a profundidade da câmara anterior, a espessura central da lente e o comprimento do segmento anterior foram avaliados. Os parâmetros avaliados foram obtidos com acomodação usando diferentes vergências de estímulo: 0,0, -1,0, -2,0 e -3,0 D. A variação desses parâmetros foi comparada para os diferentes níveis de acomodação. Resultados: A espessura corneana central não foi alterada em nenhum estímulo durante a acomodação (p>0,05). A ACD mostrou uma redução significativa (p<0,05), enquanto a espessura central da lente foi significativamente aumentada (p<0,05). O comprimento do segmento anterior também aumentou com acomodação (p<0,05) indicando um movimento do polo posterior para trás. Conclusões: Há variações significativas nos comprimentos do segmento anterior que ocorrem com acomodação. Estudar essas mudanças fornece informações úteis sobre o mecanismo de acomodação para os profissionais, a fim de obter uma melhor compreensão desse processo e ajudá-los a tomar suas decisões clínicas.

Evaluation of anterior segment parameters in patients with pseudoexfoliation syndrome using Scheimpflug imaging / Avaliação de parâmetros do segmento anterior por imagem Scheimpflug em pacientes com síndrome de pseudoexfoliação

ABSTRACT Purpose: To evaluate anterior segment parameters in patients with pseudoexfoliation syndrome (PXS) using Scheimpflug imaging. Methods: Forty-three PXS patients and 43 healthy control subjects were included in this cross-sectional study. All participants underwent a detailed ophthalmologic examination. Anterior segment parameters were measured using a Scheimpflug system. Results: Considering the PXS and control groups, the mean corneal thicknesses at the apex point (536 ± 31 and 560 ± 31 µm, respectively, p=0.001), at the center of the pupil (534 ± 31 and 558 ± 33 µm, respectively, p=0.001), and at the thinnest point (528 ± 30 and 546 ± 27 µm, respectively, p=0.005) were significantly thinner in PXS patients. Visual acuity was significantly lower (0.52 ± 0.37 versus 0.88 ± 0.23, p<0.001) and axial length was significantly longer (23.9 ± 0.70 mm versus 23.2 ± 0.90 mm, p=0.001) in the PXS eyes than in the control eyes. There were no statistically significant differences in the mean values of keratometry, anterior chamber angle, anterior chamber depth, corneal volume, and anterior chamber volume between the PXS and control eyes. Conclusions: The patients with PXS had thinner corneas, worse visual acuity, and longer axial length compared with those in the healthy controls.

RESUMO Objetivo: Avaliar os parâmetros do segmento anterior em pacientes com síndrome de pseudoexfoliação (PXS) utilizando imagens de Scheimpflug. Métodos: Quarenta e três pacientes com PXS e 43 indivíduos saudáveis foram incluídos neste estudo transversal. Todos os participantes foram submetidos ao exame oftalmológico detalhado. Parâmetros do segmento anterior foram medidos por sistema de Scheimpflug. Resultados: Considerando os grupos PXS e controle, respectivamente, as espessuras médias da espessura corneana no ápice (536 ± 31 µm e 560 ± 31 µm, p=0,001), no centro da pupila (534 ± 31 µm e 558 ± 33 µm, p=0,001), e no ponto mais fino (528 ± 30 µm e 546 ± 27 µm, p=0,005), foram significativamente mais finas em pacientes com PXS. A acuidade visual foi significativamente menor (0,52 ± 0,37 contra 0,88 ± 0,23, p<0,001) e comprimento axial foi significativamente maior (23,9 ± 0,70 milímetros contra 23,2 ± 0,90 milímetros, p=0,001) em olhos com PXS comparados com os olhos controle. Não houve diferenças estatisticamente significativas entre PXS e controle olhos em valores médios de ceratometria, ângulo da câmara anterior, profundidade da câmara anterior, volume da córnea e volume de câmara anterior. Conclusões: Os pacientes com PXS tem córneas mais finas, pior acuidade visual, e maior comprimento axial em comparação com controles saudáveis.

Aplicações clínicas do princípio de Scheimpflug na Oftalmologia / Clinical applications of the Scheimpflug principle in Ophthalmology

RESUMO Este artigo apresenta uma revisão dos princípios e das aplicações clínicas do princípio de Scheimpflug na área da imagiologia do segmento anterior. Ao disponibilizar uma imagem tridimensional do segmento anterior, esta tecnologia permite a caraterização da elevação e curvatura das superfícies anterior e posterior da córnea, o mapeamento paquimétrico, o cálculo do poder refrativo total da córnea e a biometria do segmento anterior. Na subespecialidade de cirurgia refrativa, esta abordagem melhora a capacidade de identificação de casos com risco de desenvolver ectasia, bem como de planeamento e de avaliação dos resultados dos procedimentos cirúrgicos. Recentemente, esta tecnologia foi introduzida na avaliação biomecânica in vivo da córnea e na cirurgia de catarata assistida por laser de femtossegundo.

ABSTRACT This article presents a review of the principles and clinical applications of the Scheimpflug principle in the anterior segment imaging. By providing a three-dimensional image of the anterior segment, this technology provides elevation and curvature data of the anterior and posterior surfaces of the cornea, pachymetric mapping, the total refractive power of the cornea and the anterior segment biometry. For the refractive surgery sub-specialty, this approach improves the ability to identify cases at risk of ectasia, as well as the planning and evaluation of the results of surgical procedures. Recently, this technology was introduced in corneal biomechanical in vivo evaluations and in femtosecond laser-assisted cataract surgery.

Clinical and Anterior Segment Anatomical Features in Primary Angle Closure Subgroups Based on Configurations of Iris Root Insertion

PURPOSE: To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion. METHODS: Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT(0), IT(500), IT(750), and IT(1500)), lens vault, iris area, angle opening distance (AOD(500)), angle recess area (ARA(750)), and trabecular iris space area (TISA(750)) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG). RESULTS: In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT(0) (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm2, p = 0.045), lower ARA(750) (0.112 ± 0.08 vs. 0.154 ± 0.08 mm2, p = 0.017) and AOD(500) (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG. CONCLUSIONS: The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.

Evaluation of Anterior Segment Parameter Changes Using the Sirius after Uneventful Phacoemulsification

PURPOSE: To investigate changes in anterior chamber depth (ACD), corneal volume (CV), anterior chamber angle (ACA), anterior chamber volume (ACV), central corneal thickness (CCT), horizontal visible iris diameter (HVID), pupil diameter (PD), and intraocular pressure (IOP) after uneventful phacoemulsification cataract surgery with intraocular lens implantation. METHODS: A total of 132 eyes of 132 patients (87 men and 45 women) that underwent uneventful phacoemulsification cataract surgery and intraocular lens implantation were prospectively studied. The mean age of the patients was 63.68 ± 12.51 years. All patients were evaluated preoperatively and at 1 month postoperatively with the Sirius 3D Rotating Scheimpflug camera topography system. The ACD, CV, ACA, ACV, CCT, HVID, and PD measurements were recorded. IOP was measured using the Goldmann applanation tonometer, which was corrected for CCT of the Sirius device using Ehlers' formula. RESULTS: The preoperative mean ACD, ACV, ACA, CCT, CV, PD, HVID, and IOP were 2.79 ± 0.45 mm, 124.73 ± 25.72 mm³, 42.09 ± 7.49⁰, 523.87 ± 41.97 microns, 55.37 ± 4.89 mm³, 3.98 ± 1.23 mm, 11.72 ± 0.67 mm, and 14.74 ± 2.59 mmHg, respectively. Three months postoperatively, the mean ACD, ACV, ACA, CCT, CV, PD, HVID, and IOP were 3.45 ± 0.6 mm, 162.52 ± 23.79 mm³, 51.46 ± 5.63⁰, 526.21 ± 44.45 microns, 56.23 ± 5.12 mm³, 2.87 ± 0.45 mm, 11.91 ± 0.75 mm, and 12.02 ± 1.83 mmHg, respectively. There was a statistically significant increase in mean postoperative ACD, ACV, ACA, CV, and HVID compared with the corresponding preoperative values (p < 0.05). CCT remained stable after surgery. Postoperative PD and IOP were significantly decreased compared to corresponding preoperative values (p < 0.05). CONCLUSIONS: Preoperative measurements by the Sirius 3D Rotating Scheimpflug camera topography system might help surgeons to predict postoperative changes resulting from phacoemulsification and intraocular lens implantation. This is a noncontact, noninvasive, and comfortable system for patients that is highly reliable and repeatable for anterior segment measurements.

Repeatability of central corneal thickness measurement with the Pentacam HR system / Reprodutibilidade da medida da espessura central da córnea com o sistema Pentacam HR

PURPOSE: To assess the repeatability of central corneal thickness measurement at the geometrical center (Central Corneal Thickness - CCT) given by the Pentacam High Resolution (HR) Comprehensive Eye Scanner (Oculus, Wetzlar, Germany) over time. METHODS: Prospective, single center, observational study. Two separate CCT measurements were taken by the Pentacam corneal tomography exam (CTm) 3 to 12 months apart, and compared. RESULTS: One hundred and sixteen eyes (n=116) of 62 health patients were included in this study. Average CCT in first and last visits was 541.6±37 µm and 543.6±36.9 µm respectively. Mean difference between both measurements was 9.2±6.4 µm, and there was no statistically significant difference in CCT measurement between visits, with good correlation between them (P = 0.057, r² = 0,9209). CONCLUSION: Pentacam (HR) CTm gives repeatable CCT measurements over time.

OBJETIVO: Avaliar a reprodutibilidade da medida da espessura corneana central, no seu centro geométrico, com medidas obtidas pelo sistema Pentacam de Alta Resolução (HR) com o decorrer do tempo. MÉTODOS: Realizado estudo observacional prospectivo em Centro Oftalmológico. Duas medidas isoladas da espessura central da córnea (ECC) foram realizadas com exame de tomografia do segmento anterior Pentacam HR em períodos com intervalos maiores que 3 e em até 12 meses, sendo então comparadas os resultados. RESULTADOS: Cento e dezesseis olhos (n = 116) de 62 pacientes saudáveis foram incluídos neste estudo. A média das medidas da ECC na primeira e na última avaliação foi de 541,6 ± 37 µm e 543,6 ± 36,9 µm, respectivamente. A diferença média entre as duas medições foi de 9,2 ± 6,4 µm, e não houve diferença estatisticamente significativa das medida da ECC entre as visitas, com boa correlação entre si (P = 0,057, r2 = 0,9209). CONCLUSÃO: O Tomógrafo de Segmento Anterior Pentacam HR apresentou medidas de ECC reprodutíveis ao longo do tempo.

Comparison of immersion ultrasonography, ultrasound biomicroscopy and anterior segment optical coherence tomography in the evaluation of traumatic phacoceles.

Blunt ocular trauma in the elderly can result in anterior dislocation of the crystalline lens into the subconjunctival space (phacocele). Although rare, this presentation can be missed, especially if the patient presents several days after the injury and if the lid is not everted on examination. While a careful clinical examination is adequate in the diagnosis, imaging techniques can be put to use for the accurate location of the associated sclera rupture. We report three cases of post-traumatic phacocele wherein ultrasound biomicroscopy (UBM) was compared to the anterior segment optical coherence tomography (AS-OCT) and B-scan ultrasonography (B-scan), in order to establish the best imaging tool for this condition. We concluded, based on image quality, that UBM could be the imaging modality of choice to aid in the diagnosis of phacocele.

Post-penetrating keratoplasty glaucoma.

Post-penetrating keratoplasty (post-PK) glaucoma is an important cause of irreversible visual loss and graft failure. The etiology for this disorder is multifactorial, and with the use of new diagnostic equipment, it is now possible to elucidate the exact pathophysiology of this condition. A clear understanding of the various mechanisms that operate during different time frames following PK is essential to chalk out the appropriate management algorithms. The various issues with regard to its management, including the putative risk factors, intraocular pressure (IOP) assessment post-PK, difficulties in monitoring with regard to the visual fields and optic nerve evaluation, are discussed. A step-wise approach to management starting from the medical management to surgery with and without metabolites and the various cycloablative procedures in cases of failed filtering procedures and excessive perilimbal scarring is presented. Finally, the important issue of minimizing the incidence of glaucoma following PK, especially through the use of oversized grafts and iris tightening procedures in the form of concomitant iridoplasty are emphasized. It is important to weigh the risk-benefit ratio of any modality used in the treatment of this condition as procedures aimed at IOP reduction, namely trabeculectomy with antimetabolites, and glaucoma drainage devices can trigger graft rejection, whereas cyclodestructive procedures can not only cause graft failure but also precipitate phthisis bulbi. Watchful expectancy and optimal time of intervention can salvage both graft and vision in this challenging condition.

A Case Report on the Change of the Refractive Power After a Blunt Trauma

PURPOSE: To determine the pathogenesis of transient myopia after blunt eye trauma. METHODS: In one patient, the refraction of both eyes (the left eye was injured, but the right eye was not) was measured with an autorefractometer. The cycloplegic refraction was measured at the early stage of trauma and again 3 months after the blunt eye injury. The angle and depth of the anterior chamber, the ciliary body, and the choroids were examined by ultrasound biomicroscopy (UBM) over 3 months. The depth of the anterior chamber, the thickness of the lens, and the axial length were measured by A-scan ultrasonography in both eyes. During the 3 months after the injury, we made comparisons between the menifest and the cycloplegic refractions, the depths of anterior chambers, the thickness of the lenses, the axial lengths, and the UBM-determined appearances of the angles and depths of the anterior chambers, the ciliary bodies, and the choroids in both eyes. RESULTS: We suspect that the depth reduction in the anterior chamber, the increase in anterior to posterior lens diameter, and the edema in the ciliary body are all related to the change in the refractive power following the blunt trauma. CONCLUSIONS: Ultrasound biomicroscopy (UBM) and ultrasonography of the anterior segment in the eye may be helpful to diagnose and confirm changes in the refractive power that occur after trauma.

A Case Report on the Change of the Refractive Power After a Blunt Trauma

PURPOSE: To determine the pathogenesis of transient myopia after blunt eye trauma. METHODS: In one patient, the refraction of both eyes (the left eye was injured, but the right eye was not) was measured with an autorefractometer. The cycloplegic refraction was measured at the early stage of trauma and again 3 months after the blunt eye injury. The angle and depth of the anterior chamber, the ciliary body, and the choroids were examined by ultrasound biomicroscopy (UBM) over 3 months. The depth of the anterior chamber, the thickness of the lens, and the axial length were measured by A-scan ultrasonography in both eyes. During the 3 months after the injury, we made comparisons between the menifest and the cycloplegic refractions, the depths of anterior chambers, the thickness of the lenses, the axial lengths, and the UBM-determined appearances of the angles and depths of the anterior chambers, the ciliary bodies, and the choroids in both eyes. RESULTS: We suspect that the depth reduction in the anterior chamber, the increase in anterior to posterior lens diameter, and the edema in the ciliary body are all related to the change in the refractive power following the blunt trauma. CONCLUSIONS: Ultrasound biomicroscopy (UBM) and ultrasonography of the anterior segment in the eye may be helpful to diagnose and confirm changes in the refractive power that occur after trauma.

Ultrasound biomicroscopic study of anterior segment changes after phacoemulsification and intraocular lens implantation

To study the changes in anterior segment configuration after phacoemulsification and intraocular lens implantation by means of ultrasound biomicroscopy [UBM]. Fifteen eyes of 15 patients with senile on presnile cataract and no other illness were participate in this work. All patients were examined with UBM before and one month after surgery. At each UBM examination, central anterior chamber depth [ACD1], depth from the cornea to the pupillary plane [ACD2], angle opening distance at 500 micron from scleral spur [AOD500] and trabecular iris angle [TIA] were recorded. Central anterior chamber depth increased after surgery as well angle opening distance and trabecular iris angle at 500u from scleral spur. After phacoemulsification, UBM revealed that deepening of the anterior chamber and widening of its angle occurred. This finding may be of clinical importance in patients with closed angle glaucoma

Experimentally designed glaucoma implant surgery with mitomycin C in rabbit

An attempt was made to observe the possibility of controlling intraocular pressure (IOP) without hypotony and ocular motility disorder by installing an experimentally designed glaucoma implant through a small conjunctival incision with the aid of a stylet and maintaining the aqueous reservoir using mitomycin C (MMC). The implant was made of silicone tube, of which one end was occluded by glue and on the same end 4 check-valve-like slits were made. Thirty-five healthy white rabbits were used and subdivided into 4 groups. In groups I to III, implants having 2.0, 2.5, 3.0 mm slit lengths, respectively, were installed with MMC application in one eye of each of the 10 rabbits. In group IV, a 2 mm slit-length implant was installed without MMC in one eye of each of the 5 rabbits. Pneumatonometry and ultrasonography were performed to check the IOP and the formation of aqueous reservoir in the implanted eyes for 8 weeks. In group I through III, there was a statistically significant 4-5 mmHg pressure-lowering effect in the implanted eyes compared to the contralateral control eyes for 8 weeks. The aqueous reservoirs were observed throughout the follow-up period. In group IV, we could observe neither a pressure-lowering effect nor aqueous reservoir formation in the implanted eyes after 2 weeks postoperatively. Hypotony did not occur in implanted eyes in any of the groups. This study shows the possibility of IOP control by installing a specially designed glaucoma implant with application of MMC.