Relationships between corneal biomechanics and the structural and functional parameters of glaucoma damage / Relações entre a biomecânica da córnea e os parâmetros estruturais e funcionais do dano do glaucoma

ABSTRACT Purpose: To investigate the relationships between (i) thickness of the retinal nerve fiber layer, optic nerve head topography, and visual field parameters and (ii) corneal biomechanical properties in normal controls and patients with ocular hypertension and primary open-angle glaucoma. Methods: This observational, cross-sectional study included 68 eyes with primary open-angle glaucoma, 99 eyes with ocular hypertension and 133 control eyes. Corneal biomechanical properties, optic nerve head topographic features, retinal nerve fiber layer thickness, and visual fields were assessed in all cases. Corneal biomechanical properties, retinal nerve fiber layer thicknesses, and optic nerve head topographic features were compared among the groups. The associations between structural and functional measures of glaucomatous damage and corneal biomechanical factors were also evaluated. Results: Significantly lower corneal hysteresis and corneal resistance factor values were observed in the primary open-angle glaucoma and ocular hypertension groups as compared with the control group, but there were no significant differences between the primary open-angle glaucoma and ocular hypertension groups. In the ocular hypertension group, no associations were observed between the corneal hysteresis and corneal resistance factor with values and the structural and functional parameters. In the primary open-angle glaucoma group, positive correlations were observed between the corneal hysteresis values and the global retinal nerve fiber layer thickness (p<0.01, r=0.27), mean retinal nerve fiber layer thickness (p<0.01, r=0.33), and mean deviation (p<0.01, r=0.26), and negative correlations were observed between the corneal resistance factor values, and the cup area (p<0.01, r=-0.39), cup-to-disk ratio (p=0.02, r=-0.28), linear cup-to-disk ratio (p=0.02, r=-0.28), and cup shape (p=0.03, r=-0.26). In the control group, weak correlations were detected between the corneal hysteresis and the cup area (p=0.03, r=0.19), cup-to-disk ratio (p=0.01, r=0.21), and linear cup-to-disk ratio (p=0.01, r=0.22). Conclusions: Distinct correlations were identified between the corneal hysteresis and corneal resistance factor values and the functional and structural parameters in the primary open-angle glaucoma and control groups. Corneal hysteresis and corneal resistance factor may have different roles in the pathophysiology of glaucoma.

RESUMO Objetivo: Investigar as relações entre (i) espessura da camada de fibras nervosas da retina, topografia do nervo óptico e parâmetros do campo visual e (ii) propriedades biomecânicas da córnea, em controles normais e pacientes com hiperten são ocular e glaucoma primário de ângulo aberto. Métodos: Este estudo observacional, transversal, incluiu 68 olhos com glaucoma primário de ângulo aberto, 99 olhos com hipertensão ocular e 133 olhos controle. As propriedades biomecânicas da córnea, as características topográficas da cabeça do nervo óptico, a espessura da camada de fibras nervosas da retina e os campos visuais foram avaliados em todos os casos. As propriedades biomecânicas da córnea, a espessura da camada de fibras nervosas da retina e as características topográficas da cabeça do nervo óptico foram comparadas entre os grupos. As associações entre medidas estruturais e funcionais de danos glaucomatosos e fatores biomecânicos da córnea também foram avaliadas. Resultados: Valores de histerese corneana e da resistência corneana foram significativamente menores nos grupos com glaucoma primário de ângulo aberto e hipertensão ocular em com paração ao grupo controle, mas não houve diferenças significativas entre os grupos de glaucoma primário de ângulo aberto e hipertensão ocular. No grupo com hipertensão ocular, não foram observadas associações entre histerese da córnea e o fator de resistência corneana com os valores e os parâmetros estruturais e funcionais. No grupo com glaucoma primário de ângulo aberto foram observadas correlações positivas entre os valores de histerese corneana e a espessura a camada de fibras nervosas da retina (p<0,01, r=0,27), espessura média da camada de fibras nervosas da retina (p<0,01, r=0,33) e desvio médio (p<0,01, r=0,26), e correlações negativas entre o os valores do fator de resistência da córnea e a área de escavação (p<0,01, r=-0,39), a relação escavação/disco (p=0,02, r=-0,28), a relação copo-para-disco linear (p=0,02, r=-0,28) e a forma da escavação (p=0,03, r=-0,26). No grupo controle, correlações foram detectadas entre a histerese da córnea e área de escavação (p=0,03, r=0,19), relação escavação/disco (p=0,01, r=0,21) e relação copo-para-disco linear (p=0,01, r=0,22). Conclusões: Correlações distintas foram identificadas entre histerese da córnea e os valores de resistência da córnea e os parâmetros funcionais e estruturais nos grupos de glaucoma primário de ângulo aberto e controle. A histerese da córnea e o fator de resistência da córnea podem ter diferentes papéis na fisiopatologia do glaucoma.

The effect of pseudoexfoliation syndrome on choroidal thickness in open-angle glaucoma / O efeito do glaucoma pseudoesfoliativo sobre a espessura da coroide em comparação com o glaucoma de ângulo abertos

ABSTRACT Purpose: To investigate the effect of pseudoex foliation syndrome on choroidal thickness as compared with healthy individuals and subjects with primary open-angle glaucoma. Methods: This prospective, randomized study included 30 primary open angle glaucoma patients and 30 pseudoexfoliation glaucoma patients with similar demographic characteristics and 30 eyes of 30 healthy individuals comprised the control group. Regular optic nerve and macular images were obtained using a Cirrus HD spectral domain optical coherence tomography instrument, along with macular choroidal thickness measurements with enhanced depth imaging mode. Results: Age, sex, and axial length values were similar among the three groups (p>0.05). The primary open angle glaucoma and pseudoexfoliation glaucoma groups had comparable levels of glaucomatous damage. The mean subfoveal choroidal thickness values in the primary open angle glaucoma, pseudoexfoliation glaucoma, and control groups were 271.80 ± 19.96 μm, 241.43 ± 32.47 μm, and 268.03 ± 24.50 μm, respectively. The pseudoexfoliation glaucoma group had the lowest choroidal thickness values of the three groups (p values: pseudoexfoliation-control: 0.001; pseudoexfoliation-primary open angle glaucoma: <0.001, primary open angle glaucoma-control: 0.516, independent samples t-test). Conclusion: The macular choroid was thinner in patients with pseudoexfoliation glaucoma, as compared with both healthy individuals and open-angle glaucoma patients with similar degrees of glaucomatous damage.

RESUMO Objetivo: Investigar o efeito do glaucoma pseudoexfoliativo sobre a espessura da coroide em comparação com indivíduos saudáveis e com glaucoma primário de ângulo aberto. Métodos: Este estudo prospectivo e randomizado incluiu 30 pacientes com glaucoma primário de ângulo aberto e 30 com glaucoma pseudoexfoliativo, com características demográficas semelhantes e 30 olhos de 30 indivíduos saudáveis compuseram o grupo controle. Imagens da área macular e do nervo óptico foram obtidas usando um tomógrafo por coerência óptica no domínio espectral do modelo Cirrus HD, juntamente com medições da espessura da coroide na área macular através do modo de imagem de profundidade realçada. Resultados: Os valores de idade, sexo e comprimento axial foram semelhantes nos três grupos (p>0,05). Os grupos de glaucoma primário de ângulo aberto e de glaucoma pseudoexfoliativo tinham níveis comparáveis de lesões glaucomatosas. Os valores médios da espessura subfoveal da coroide nos grupos do glaucoma primário de ângulo aberto, glaucoma pseudoexfoliativo e de controle foram 271,80 ± 19,96 μm, 241,43 ± 32,47 μm e 268,03 ± 24,50 μm, respectivamente. O grupo glaucoma pseudoexfoliativo apresentou os menores valores de espessura de coroide dos três grupos (valores de p: pseudoexfoliativo-controle: 0,001; pseudoexfoliativo-glaucoma primário de ângulo aberto: <0,001, controle de glaucoma primário de ângulo aberto: 0,516; teste de t de amostras independentes). Conclusão: A coroide na área macular era mais fina em pacientes com glaucoma pseudoexfoliativo, quando comparada com indivíduos saudáveis e pacientes com glaucoma de ângulo aberto com graus similares de lesão glaucomatosa.

Normal-tension glaucoma: an update / Glaucoma de pressão normal: atualização

ABSTRACT Normal-tension glaucoma (NTG) is a progressive optic neuropathy with intraocular pressure (IOP) within the statistically normal range (≤21 mmHg). The prevalence of NTG varies widely among different population studies, being the most prevalent open-angle glaucoma subtype in some reports. The etiology of NTG possibly is multifactorial and still not well defined. Alternative treatments have been proposed based on pathogenesis details. However, in clinical practice, adequate reduction of IOP remains the keystone of managing patients with NTG. We review the pathogenesis of NTG and the available therapies for this optic neuropathy.

RESUMO O glaucoma de pressão normal (GPN) é uma neuropatia óptica progressiva que cursa com a pressão intraocular (PIO) dentro da faixa de normalidade (≤21 mmHg). A prevalência do glaucoma de pressão normal varia entre os estudos populacionais, sendo em alguns o principal subtipo de glaucoma primário de ângulo aberto. A etiologia do glaucoma de pressão normal possivelmente é multifatorial e ainda não foi totalmente esclarecida. Tratamentos alternativos baseados nos diferentes detalhes da patogenia foram recentemente propostos. Entretanto, na prática clínica, a redução adequada da pressão intraocular continua sendo a base do tratamento do glaucoma de pressão normal. O objetivo deste artigo é revisar a patogênese do glaucoma de pressão normal e as formas de terapia disponíveis.

Glaucoma de ángulo abierto posterior a la vitrectomía pars plana / Open angle glaucoma after pars plana vitrectomy

Con este trabajo nos proponemos revisar las evidencias científicas relacionadas con la aparición del glaucoma de ángulo abierto posterior a la vitrectomía pars plana. Se revisaron las evidencias científicas relacionadas con la aparición del glaucoma de ángulo abierto posterior a la cirugía de vitrectomía pars plana. Para la investigación documental se examinaron los artículos de la temática indexados en las bases de datos Pubmed, Pubmed Central y Scielo, que correspondieron a los descriptores DeCs-MeSH: glaucoma de ángulo abierto y vitrectomía pars plana. En la búsqueda de avanzada se utilizó el booleano AND y la restricción de tiempo entre los años 2004 y 2014. De los 38 artículos identificados, se desecharon 16 por no tenerse acceso íntegro al documento. El tratamiento de los datos se realizó mediante el análisis de contenido de tipo directo. Los mecanismos patológicos que causan glaucoma de ángulo abierto posterior a la vitrectomía pars plana son múltiples y complejos. La hipótesis del daño por estrés oxidativo en las celdas de la malla trabecular y su repercusión en la salida del humor acuoso, tiene un sustento científico en su patogenia que la hace plausible. El tratamiento para controlar la hipertensión ocular en estos pacientes después de la vitrectomía es individualizado; puede transitar desde el tratamiento médico y hasta el uso de técnicas quirúrgicas simples o complejas en algunos casos. Aún no se han esclarecido los mecanismos fisiopatológicos del glaucoma de ángulo abierto posterior a la vitrectomía pars plana, por lo que son necesarias nuevas investigaciones sobre el tema(AU)

Scientific evidence related with occurrence of the open angle glaucoma after pars plana vitrectomy surgery were reviewed. For the purpose of the documentary research, the articles about this topic indexed in Pubmed-PubmedCentral-Scielo databases were revised, using the subject headings "open angle glaucoma" and "pars plana vitrectomy". The advanced search used Boolean AND and time restriction between 2004 and 2014. Of 38 identified articles, 16 had to be discarded since they could not be fully accessed. Data were processed through the direct contents analysis. The pathological mechanisms that cause open angle glaucoma after pars plana vitrectomy are numerous and complex. The hypothesis about the oxidative stress damage in the trabecular mesh cells and its effect in the discharge of aqueous humor has a scientific foundation in its pathogeny that makes it plausible. The treatment to manage the ocular hypertension in these patients after vitrectomy is customized; it may go from medical treatment to the use of simple or complex surgical techniques in some cases. The physiopathological mechanisms of the open angle glaucoma after pars plana vitrectomy have not been clarified yet, so new research on the topic is needed. This paper was aimed at reviewing the scientific evidence linked to the occurrence of open angle glaucoma after pars plana vitrectomy(AU)

Relevância da biomecânica da córnea no glaucoma / Relevancy of corneal biomechanical in glaucoma

Relato de caso de uma paciente, com córnea espessa, por distrofia de Fuchs em fase inicial, ainda com transparência corneana preservada (edema corneano subclínico), associado à pressão intraocular (PIO) normal por tonometria de aplanação de Goldman (TAG), que teve entretanto, o diagnóstico de glaucoma primário de ângulo aberto com base em alterações estruturais do nervo óptico. O estudo tomográfico demonstrou padrão de paquimetria espacial compatível com edema sub-clínico. O estudo biomecânico da córnea com o ORA (Ocular Response Analyzer, ® Reichert), associado à medida corrigida da PIO, possibilitou o entendimento da influência da córnea, que apesar de mais espessa, levava a uma TAG falsamente reduzida (hipoestimada). O estudo da PIO com sistema de tonografia digital de contorno (PASCAL) corroborou com os achados do ORA. Este exemplo ressalta a importância de novas tecnologias na avaliação de pacientes com suspeita de glaucoma, e destaca que a correção da TAG, com base em algoritmos lineares relacionados com a paquimetria central apenas, pode determinar sérios erros de interpretação clínica.

Case report of a patient, with a thick cornea, for Fuchs dystrophy in its early stages, yet with preserved corneal transparency (subclinical corneal edema), associated with normal intraocular pressure (IOP) by Goldman applanation tonometry (GAT), which was however, the diagnosis of primary open-angle glaucoma on the basis of structural changes of the optic nerve. The tomographic study showed a pattern of spatial pachymetry compatible with subclinical edema. The corneal biomechanical study with ORA (Ocular Response Analyzer, Reichert ®) associated with corrected IOP measurement, allowed the understanding of the corneal influence, which, although thicker, leading to a falsely low TAG (underestimated). The IOP study with tonography system digital (PASCAL) corroborated with the findings of ORA. This example highlights the importance of new technologies in patients' evaluation with suspected glaucoma, and highlights that the correction of TAG, based on linear algorithms related to central corneal thickness alone, can determine serious errors in clinical interpretation.

Comparison of Retinal Nerve Fiber Layer Thickness between Stratus and Spectralis OCT

PURPOSE: To compare the peripapillary retinal nerve fiber layer (RNFL) thickness of normal patients and those with various glaucoma diseases by time domain (Stratus) and spectral domain (Spectralis) optical coherence tomography (OCT). METHODS: The RNFL thickness as measured by the Stratus and Spectral OCT was compared (paired t-test). The relationship and agreement of RNFL thickness between the two OCT modalities were evaluated by Pearson correlation, Bland-Altman plot, and area under the receiver operating characteristic curve. RESULTS: Two-hundred seventeen eyes of 217 patients, including twenty-four normal eyes, ninety-one glaucoma suspects, seventy-six normal tension glaucoma cases, and twenty-six primary open angle glaucoma cases (POAG) were analyzed. The peripapillary RNFL thicknesses as measured by Stratus OCT were significantly greater than those measured by Spectralis OCT. However, in quadrant comparisons, the temporal RNFL thickness obtained using Stratus OCT were significantly less than those obtained using Spectralis OCT. Correlations between RNFL parameters were strong (Pearson correlation coefficient for mean RNFL thickness = 0.88); a high degree of correlation was found in the POAG group. Bland-Altman plotting demonstrated that agreement in the temporal quadrant was greater than any other quadrant. CONCLUSIONS: Both OCT systems were highly correlated and demonstrated strong agreement. However, absolute measurements of peripapillary RNFL thickness differed between Stratus OCT and Spectralis OCT. Thus, measurements with these instruments should not be considered interchangeable. The temporal quadrant was the only sector where RNFL thickness as measured by Spectralis OCT was greater than by Stratus OCT; this demonstrated greater agreement than other sectors.

Visual prognosis, intraocular pressure control and complications in phacomorphic glaucoma following manual small incision cataract surgery.

Aims: To evaluate intraocular pressure (IOP) control, visual prognosis and complications following manual small incision cataract surgery among eyes with phacomorphic glaucoma. Materials and Methods: This prospective, non-randomized interventional consecutive case series included all patients with phacomorphic glaucoma who presented to a tertiary eye care referral center in South India between March 2006 and April 2007. All patients underwent slit-lamp bio-microscopy, applanation tonometry and gonioscopy of the other eye to rule out angle closure. Small incision cataract surgery with intraocular lens implantation was performed in all affected eyes. Complete ophthalmic examination was done at each follow-up visit. Results: A total of 74 eyes with phacomorphic glaucoma were included in this study. The preoperative mean IOP was 38.4±14.3 mmHg and mean IOP at last follow-up was 12.7±2.4 mmHg. There was a statistically significant difference between IOP at presentation and IOP at last follow-up (P< 0.001). None of the eyes required long-term antiglaucoma medication. No significant intraoperative complications were noted. The final postoperative best corrected visual acuity was 20/40 or better in 51 patients. Eighteen eyes had corneal edema and 36 eyes had anterior chamber inflammation. Both conditions resolved with standard medical therapy. Conclusion: Manual small incision cataract surgery is safe and effective in controlling IOP and achieving good functional visual acuity with minimal complications in the management of phacomorphic glaucoma in developing countries.

Medical decision, persistence of initial treatment, and glaucoma progression in a Brazilian reference hospital / Decisão médica, persistência com o tratamento inicial e progressão do glaucoma em um hospital de referência no Brasil

PURPOSE: To evaluate the initial medical decision regarding primary open-angle glaucoma (POAG) treatment in a referral center, and to assess the relationship between the persistence of treatment and the disease progression in cases managed exclusively with medication. METHODS: A retrospective chart review was performed for 65 patients with primary open-angle glaucoma referred to a tertiary hospital. The following clinical data were analyzed: initial medication, persistence of treatment, best corrected visual acuity, visual field mean deviation index, cup/disc ratio, and intraocular pressure. Patients were classified into four categories in order to verify the clinical evolution. RESULTS: The mean number of visits/ year was 4.4 ± 3.5, and the follow-up period was 40.7 ± 22.8 months. Mean persistence time was 12.9 ± 13.9 months. By six and twelve months, respectively, 39.1 percent and 62.5 percent of patients had discontinued the initially prescribed regimen, mainly by adding to (42 percent) or changing (26 percent) the course of treatment. Thirteen patients (21 percent) were reclassified to a worse category of primary open-angle glaucoma, however, despite this trend, no significant correlation was found between shorter persistence and primary open-angle glaucoma worsening. CONCLUSIONS: Persistence rates with initial therapy schemes were low, as measured by medical decisions to change the course of treatment. Therefore, improvement in the initial medical decision is crucial in order to offer a more stable and effective treatment for primary open-angle glaucoma.

OBJETIVO: Avaliar as mudanças terapêuticas, dadas por decisão médica, relativas ao tratamento do glaucoma primário de ângulo aberto em um centro de referência e a possível relação entre a persistência do tratamento e progressão da doença em casos controlados com medicação. MÉTODOS: Uma revisão de prontuários foi realizada em 65 pacientes com glaucoma primário de ângulo aberto encaminhados a um hospital terciário Os seguintes dados clínicos foram analisados: primeira medicação instituída, persistência com o tratamento inicial, melhor acuidade visual corrigida, índice ''desvio médio'' do campo visual, relação escavação/disco óptico e pressão intraocular. Os pacientes foram classificados em quatro categorias, a fim de se verificar a evolução clínica. RESULTADOS: A média do número de visitas/ano foi de 4,4 ± 3,5 e o período de seguimento foi de 40,7 ± 22,8 meses. A média de tempo persistência foi de 12,9 ± 13,9 meses. Em seis e doze meses, respectivamente, 39,1 por cento e 62,5 por cento dos pacientes tinham interrompido o regime terapêutico inicialmente previsto, principalmente pela adição (42 por cento) ou mudança (26 por cento) do esquema terapêutico. Treze pacientes (21 por cento) evoluíram para uma pior categoria de glaucoma primário de ângulo aberto, no entanto, apesar desta tendência, nenhuma correlação significativa foi encontrada entre baixa persistência e agravamento do glaucoma primário de ângulo aberto. CONCLUSÕES: As taxas de persistência com o esquema terapêutico inicial foram baixas, quando medidas através das mudanças observadas por decisões médicas, durante o curso do tratamento. Uma melhor decisão terapêutica inicial é crítica, a fim de poder se oferecer um tratamento mais estável e eficaz para o glaucoma primário de ângulo aberto.

Prevención de ceguera en pacientes con glaucoma primario de ángulo abierto / Blindness prevention in patients with primary open angle glaucoma

Se realizó una revisión bibliográfica con el objetivo de describir los aspectos fundamentales acerca de la prevención de ceguera en pacientes con glaucoma primario de ángulo abierto por la importancia que tiene el diagnóstico precoz y tratamiento oportuno de dicha afección de alta frecuencia de aparición en la población. Se hace muy importante el conocimiento de los principales factores de riesgo relacionados con esta entidad pues esa será el arma fundamental del médico conjuntamente con el examen físico y oftalmológico completo para poder identificar los grupos de riesgo y/o los pacientes que ya han desarrollado glaucoma; esto nos permitirá actuar de inmediato para prevenir la progresión del defecto visual en caso de que ya exista. Toda la información obtenida a través de la literatura disponible durante el año 2008 fue representada en Microsoft Word.

A bibliography review was made to describe the most important aspects related to blindness’ prevention in patients with primary open angle glaucoma due to the importance of early diagnosis and opportune treatment of this frequent disease in our population. Also, we have to know the principal risk factors related because it will be doctor’s principal weapon in reference with physical and ophthalmologic exam to identify risk groups and patients with development of glaucoma; it will allow us to act immediately to prevent visual defect progression if it exists.All obtained information found in bibliography during 2008 was represented in Microsoft W.

Correlação entre a espessura corneana central e o comprimento axial ocular nos portadores de glaucoma e em olhos normais / Correlation between central corneal thickness and axial length in patients with glaucoma and normal eyes

OBJETIVO: Correlacionar a espessura corneana central com o comprimento axial ocular nos portadores de glaucoma primário de ângulo aberto, com glaucoma primário de fechamento angular e indivíduos com olhos normais. MÉTODOS: A amostra foi constituída de 94 olhos de 94 pacientes, divididos em três grupos compostos por 33 olhos de 33 pacientes portadores de glaucoma primário de ângulo aberto, 30 olhos de 30 pacientes com glaucoma primário de fechamento angular e 31 olhos normais de 31 indivíduos. A espessura corneana e o comprimento axial do olho foram obtidos pela paquimetria ultrassônica e ecobiometria, respectivamente. RESULTADOS: A média da espessura corneana central foi de 535,1 mm no glaucoma primário de fechamento angular; 520,6 mm no glaucoma primário de ângulo aberto e 519,2 mm nos olhos normais (p=0,18). A média do comprimento axial do globo ocular nos portadores de glaucoma primário de fechamento angular foi de 22,16 mm e nos grupos com glaucoma primário de ângulo aberto e olhos normais foram de 22,68 mm e 22,64 mm, respectivamente (p=0,13). Não houve correlação significativa entre a espessura corneana central e comprimento axial do globo ocular nos grupos com glaucoma primário de fechamento angular (r=-0,085; p=0,65), glaucoma primário de ângulo aberto (r=-0,070; p=0,69) e olhos normais (r=-0,120; p=0,52). CONCLUSÃO: Os resultados deste trabalho sugerem não haver correlação entre a espessura corneana central e o comprimento axial do globo ocular nos portadores de glaucoma e indivíduos com olhos normais.

PURPOSE: To evaluate and to correlate the central corneal thickness with the ocular axial length in patients with primary open-angle glaucoma, primary angle-closure glaucoma and individuals with normal eyes. METHODS: The sample was composed of 94 patients' eyes, divided into three groups constituted of 33 eyes of 33 primary open-angle glaucoma patients, 30 eyes of 30 primary angle-closure glaucoma patients and 31 normal eyes of 31 individuals. The central corneal thickness and the axial length were measured by ultrasonic pachymeter and biometry by A-scan ultrasound, respectively. RESULTS: The results showed a mean of 535.1 mm central corneal thickness in primary angle-closure glaucoma group, 520.6 mm in primary open-angle glaucoma group and 519.2 mm in normal eyes (p=0.18). The ocular axial length on primary angle-closure glaucoma group was 22.16 mm and on primary open-angle glaucoma and normal eyes group was 22.68 mm and 22.64 mm, respectively (p=0.13). There was no significant correlation between corneal thickness and axial length in the primary angle-closure glaucoma group (r=-0.085; p=0.65), the open-angle glaucoma group (r=-0.070; p=0.69) and the normal eyes group (r=-0.120; p=0.52). CONCLUSIONS: The results of this assay suggest that there is no correlation between the central corneal thickness and the axial length in patients with glaucoma and individuals with normal eyes.

Comparative biometric study between plateau iris configuration and primary open angle glaucoma with narrow angle / Estudo biométrico comparativo entre configuração da íris em platô e glaucoma primário de ângulo aberto com seio camerular estreito

PURPOSE: To investigate biometrically the differences between plateau iris configuration (PIC) eyes and primary open angle glaucoma with narrow angle eyes. METHODS: A comparative study involving a case series with 20 eyes of 11 plateau iris configuration patients and 45 eyes of 27 primary open angle glaucoma with narrow angle eyes patients was done. The following measurements were taken: corneal curvature, central corneal thickness, anterior chamber depth, lens thickness (LT), axial length (AL), lens thickness and axial length ratio, lens position (LP) and relative lens position (RLP). RESULTS: The plateau iris configuration eyes presented a higher corneal cuvature value than primary open angle glaucoma with narrow angle eyes eyes but not with clinical and statistical difference (P=0.090). The plateau iris configuration eyes demonstrated a higher central corneal thickness, with statistical significance, when compared to primary open angle glaucoma with narrow angle eyes (P=0.010). Statistical significant difference between plateau iris configuration and primary open angle glaucoma with narrow angle eyes was found in axial length (21.69 ± 0.98 vs. 22.42 ± 0.89; P=0.003). No significant difference was found when anterior chamber depth (2.62 ± 0.23 vs. 2.71 ± 0.31; P=0.078), LT (4.67 ± 0.36 vs. 4.69 ± 0.45; P=0.975), LT/AL (2.16 ± 0.17 vs. 2.10 ± 0.21; P=0.569), LP (4.95 ± 0.25 vs. 5.06 ± 0.34; P=0.164) and RLP (0.23 ± 0.01 vs. 0.22 ± 0.14; P=0.348) were evaluated. CONCLUSION: The eyes with plateau iris configuration presented statistical significantly shorter axial length and higher central corneal thickness than primary open angle glaucoma with narrow angle eyes.

OBJETIVO: Comparar, biometricamente, olhos portadores de configuração da íris em platô (CIP) e olhos portadores de glaucoma primário de ângulo aberto com seio camerular estreito. MÉTODOS: Estudo prospectivo comparativo envolvendo 20 olhos de 11 pacientes portadores de íris em platô e 45 olhos de 27 pacientes portadores de glaucoma primário de ângulo aberto com seio camerular estreito. Os parâmetros avaliados foram: curvatura corneana, espessura central da córnea, profundidade central da câmara anterior, espessura do cristalino (EC), comprimento axial (CAx), relação entre a espessura do cristalino e o comprimento axial (EC/CAx), posição do cristalino (PC) e posição relativa do cristalino (PRC). RESULTADOS: Os olhos com íris em platô apresentaram valores ceratométricos superiores àqueles dos olhos com glaucoma primário de ângulo aberto com seio camerular estreito, embora sem diferença clínica ou estatística (P=0,090). Os olhos com configuração da íris em platô apresentaram maior espessura central da córnea com diferença estatisticamente significativa, quando comparados aos olhos com CIP (P=0,010). Diferença estatisticamente significativa foi encontrada entre os olhos com configuração da íris em platô e os olhos com glaucoma primário de ângulo aberto com seio camerular estreito no CAx (21,69 ± 0,98 vs. 22,42 ± 0,89; P=0,003). Não houve diferença significativa entre: profundidade central da câmara anterior (2,62 ± 0,23 e 2,71 ± 0,31; P=0,078); EC (4,67 ± 0,36 e 4,69 ± 0,45; P=0,975); EC/CAx (2,16 ± 0,17 e 2,10 ± 0,21; P=0,569); PC (4,95 ± 0,25 e 5,06 ± 0,34; P=0,164) e PRC (0,23 ± 0,01 e 0,22 ± 0,14; P=0,348). CONCLUSÃO: Os olhos com configuração da íris em platô possuem menor comprimento axial e maior espessura central da córnea em comparação aos olhos com glaucoma primário de ângulo aberto com seio camerular estreito, com significância estatística.

Biomicroscopia ultra-sônica em esclerectomia profunda: relato de caso / Ultrasound biomicroscopy in deep sclerectomy: case report

Relato do caso de um paciente com diagnóstico de glaucoma primário de ângulo aberto, que foi submetida a esclerectomia profunda em olho direito, com sucesso. No pós-operatório de 3 meses, o procedimento cirúrgico foi avaliado com biomicroscopia ultra-sônica (UBM) utilizando-se dois equipamentos distintos (UBM 840-Zeiss; UBM-VUMAX-Sonomed) com transdutores de 50 MHz. O método diagnóstico com biomicroscopia ultra-sônica pode ser usado como método não invasivo para avaliar a arquitetura interna ocular na topografia da esclerectomia profunda. Permite identificar as estruturas do segmento anterior, sua relação anatômica, bem como a membrana trabéculo-Descemet íntegra e o espaço intra-escleral. Biomicroscopia ultra-sônica demonstrou utilidade na avaliação pós-operatória do procedimento cirúrgico.

Case report of a woman with the diagnosis of primary open-angle glaucoma who was submitted to a successful surgical procedure of deep sclerectomy in the right eye. In the postoperative period, at month 3, the surgical procedure was evaluated with ultrasound biomicroscopy (UBM) utilizing two distinct equipments (UBM 840-Zeiss; UBM-VUMAX-Sonomed), with 50-MHz transducers. The diagnostic method of ultrasound biomicroscopy can be utilized as a non invasive method to evaluate the internal architecture of the eye at the topography of deep sclerectomy. It allows to identify the anterior segment structures, their anatomical relationship, and also the intact trabecular-Descemet membrane and the intrascleral space. Ultrasound biomicroscopy showed to be useful in evaluating postoperative status of the surgical procedure.

Correlação clínica entre estrutura e função no glaucoma: classificação estrutural de Armaly e o sistema de estadiamento funcional de Brusini / Clinical correlation between structural and functional assessment in glaucoma: Armaly cup to disk ratio and Brusini glaucoma staging system

OBJETIVO: Avaliar a correlação entre a análise estrutural de Armaly e o estadiamento funcional de Brusini em pacientes glaucomatosos. MÉTODOS: Setenta e oito olhos de 42 pacientes com glaucoma de ângulo aberto realizaram exame de campo visual com o campímetro Humphrey Field Analyzer II (programa SITA 24-2) e avaliação do disco óptico com lente Volk 78D por dois examinadores independentes. O disco óptico foi classificado de acordo com a relação escavação/disco (C/D), de 0,1 a 1,0. Os valores do "Mean Deviation" (MD) e "Pattern Standard Deviation" (PSD) de cada olho foram inseridos na avaliação de estadiamento de Brusini, para estabelecer um valor de gravidade do glaucoma. A relação escavação/disco e os valores de Brusini foram colocados em diagrama para serem correlacionados (coeficiente de correlação de Spearman, rho). Os valores de Armaly foram transformados em escala logarítmica e os dados foram inseridos em um diagrama com os valores de Brusini para cada paciente. RESULTADOS: As análises de Armaly e Brusini apresentaram baixa correlação (rho=0,340). A correlação, não-logarítmica e logarítmica, entre Armaly e Brusini mostrou-se linear e baixa. CONCLUSÃO: Apesar da baixa correlação, a avaliação estrutural de Armaly e a análise funcional do estadiamento de Brusini proporcionaram medidas não independentes do glaucoma.

PURPOSE: To evaluate the correlation between Armaly's structural systems with Brusini's functional staging in glaucomatous patients. METHODS: Seventy-eight eyes of forty-two patients with primary open-angle glaucoma underwent visual field testing with the Humphrey Field Analyzer II (program SITA 24-2) and optic disc evaluation with the 78D Volk lens by two independent observers. Optic disc was stratified according to cup/disc ratio (C/D), from 0.1 to 1.0. Mean deviation (MD) and pattern standard deviation (PSD) values from each eye were plotted on Brusini's staging system to derive a value for glaucoma severity. Both cup/disc ratio and Brusini's values were plotted on a diagram to assess correlation (Spearman's rho correlation coefficient). Armaly's values were logged in a logarithmic figure and the data plotted on a diagram with Brusini's values for each patient. RESULTS: Armaly's and Brusini's systems dysplayed a poor correlation (rho=0.340). Both unlogged and logged, Armaly's versus Brusini's plots resulted in a linear and weak correlation. CONCLUSION: Despite the weak correlation, Armaly's structural system and Brusini's staging system provided non-independent measures for glaucoma evaluation.

Experiencia bioultrasónica en el síndrome de dispersión pigmentaria/glaucoma pigmentario, antes y después de la iridotomía láser / Bioultrasound experience in pigment dispersion syndrome and pigmentary glaucoma before and after laser iridotomy

Se estudió mediante biomicrocopia ultrasónica la morfología del iris y su relación con las estructuras intraoculares del segmento anterior en el síndrome de dispersión pigmentaria/glaucoma pigmentario, y el efecto de la iridotomía Nd YAG láser. Se estudiaron 14 ojos de 14 pacientes que presentaron Huso de Krukenberg bilateral sin afección ocular previa (excepto glaucoma), a los cuales se les realizó la biomicrocopia ultrasónica inmediatamente antes y una semana después del tratamiento con iridotomía láser para evaluar la morfología del iris, el grado de apertura angular, la distancia de apertura angular, y la presencia de contactos iridocristaliniano, iridozonular e iridociliar. Se demostró la presencia de concavidad iridiana en 66,7 por ciento de los ojos y convexidad en 33,3 por ciento. El contacto iridozonular estuvo presente en 50 por ciento, lográndose una disminución importante en el área de contacto luego de la iridotomía láser en todos los casos, mientras que el contacto iridociliar presente en 11,1 por cientono mostró ninguna variación. La iridotomía láser rectificó la concavidad iridiana y disminuyó el área de contacto iridozonularm, beneficiando los pacientes con concavidad iridiana. Se precisa un estudio exhaustivo de los mecanismos favorecedores de la dispersión de pigmento en ausencia de concavidad iridiana y su posible tratamiento.

The morphology of the iris and its relation to intraocular structures of the anterior segment in the pigment dispersion syndrome/pigmentary glaucoma, as well as Nd YAG laser iridotomy were studied through ultrasound biomicroscopy. Fourteen eyes from 14 patients, who presented with bilateral Krukenberg´s spindle without previous ocular problem (except for glaucoma) were studied and performed ultrasound biomicroscopy inmediately before and a week after laser iridotomy in order to evaluate the iris morphology, angle aperture, angle aperture distance and the presence of iridocrystalline, iridozonular and iridociliary contacts. Iridian concavity was detected in 66.7 percent of the eyes whereas convexity was present in 33.3 percent of them. Iridozonular contact was in 50 percent f cases, reaching an important reduction of the contact area after laser iridotomy in all the cases, whereas iridociliary contact observed in 11.1 percent of subjects did not show any variation. Laser iridotomy corrected iridian concavity and at the same time, it reduced the contacting area iridozonularm, thus helping the patients with iridian concavity. It is necessary to carry out a thorough study of favouring mechanisms of pigment dispersion when iridian concavity does not exist, and the possible treatment of this entity.

Comparison of Retinal Nerve Fiber Layer Measurements between NTG and HTG using GDx-VCC

PURPOSE: To compare quantitative polarimetric measurements in eyes with NTG and HTG using GDx-VCC. Both groups were matched by age and glaucoma stage based on the Humphrey visual field test. METHODS: We retrospectively reviewed the records of 146 patients who underwent Humphrey field analysis (HFA) and GDx-VCC. We compared outcomes of retinal nerve fiber layer (RNFL) parameters among the three groups by ANOVA and between each pair of groups using the Tukey-Kramer Post-Hoc test. We also evaluated the sensitivity and specificity of GDx-VCC in detecting glaucoma in each group. RESULTS: The mean age and HFA mean deviation (MD) were 55.6+/-9.5 years and -0.8+/-1.5 dB in 47 control patients, 59.4+/-9.0 years and -5.77+/-4.38 dB in 49 NTG patients, and 59.4+/-11.7 years and -8.09+/-6.77 dB in 51 HTG patients, respectively. All thickness parameters were lower in HTG patients compared to NTG patients, but there were no significant differences in ratio parameters between age-matched early HTG and NTG patients. The sensitivity of GDx-VCC was significantly higher in both early and total HTG patients compared to the respective groups of NTG patients. CONCLUSIONS: Compared to eyes with NTG, eyes with HTG showed reduced RNFL thickness and ratio parameters when patients were age and visual field matched. GDx-VCC appeared to be more sensitive in detecting RNFL damage in HTG patients.

Optic disc size in ocular hypertension.

PURPOSE: To study the optic disc size in eyes with ocular hypertension (OHT) in comparison to primary open-angle glaucoma (POAG) and normals. METHODS: Optic disc photographs obtained with the Nidek 3dx NM camera were digitized (Nikon coolscan) and disc area calculated using Littmann correction in a randomly chosen eye of 28 OHT, 42 POAG and 30 normal subjects. OHT was defined as increased intraocular pressure with no disc or field changes suggestive of glaucoma with open angles. RESULTS: The optic disc area in OHT was 9.47 +/- 1.09 mm2; 12.27 +/- 2.87 mm2 in POAG; and 12.11 +/- 2.83 mm2 in normal individuals. CONCLUSION: Using magnification corrected morphometry and the criteria for OHT diagnosis, the optic disc area in OHT was significantly smaller (p < 0.0001) in POAG and normals.

Eficacia y seguridad del Latanoprost: en pacientes con glaucoma abierto e hipertensión ocular / Efficacy and security of the Latanoprost in patients with open glaucoma e ocular hypertension

Determinar el tiempo mínimo necesario del Latanoprost al 0.005 por ciento para controlar la presión intraocular, el porcentaje de reducción de la misma y los efectos colaterales a corto plazo. Un total de 35 pacientes con glaucoma de ángulo abierto e hipertensos oculares; participaron en un estudio prospectivo, longitudinal realizado en el Hospital Universitario de Maracaibo. Los pacientes recibieron Latanoprost al 0.005 por ciento (Xalatan R) una vez al día, a las 8:00 pm, siendo medida la presión intraocular al 1,3,30,60 y 90 días luego de su administración. En 65 ojos de 35 pacientes, la presión inicial promedio fue de 21.0ñ7.7 (11-52) para el ojo derecho y el izquierdo 21,8 ñ 7.2 (13-50). El Latanoprost reduce la presión intraocular a las primeras 24 horas 3.58 mmHg ñ6.81, al primer mes 4.70 mmHg ñ7.23; segundo mes 4.26 mmHg ñ7.06 y 7.76 mmHg + 7.36 al tercer mes. El porcentaje de reducción de la presión al primer mes fue de un 20 por ciento en un 57.2 por ciento de la población estudiada, mayor del 20 por ciento en un 39.6 por ciento de los pacientes, de este un 12.6 por ciento es mayor al 40 por ciento la reducción. Al tercer mes la reducción es mayor 20 por ciento en el 45.0 por ciento, correspondiendo el 19.6 por ciento a mayor del 40 por ciento y menor al 20 por ciento de reducción en un 54.9 por ciento. Siendo significativa la reducción de la presión intraocular (p<0.005, con efectos colaterales a corto plazo mínimo. El resultado del estudio demostró que el Latanoprost al 0.005 por ciento, utilizado una sóla vez al día produce una significativa reducción de la presión intraocular desde las primeras 24 horas de su administración, brindando seguridad y eficacia en el tratamiento de glaucoma de ángulo abierto e hipertensos oculares. Este es un estudio preliminar que se realizará durante un año para evaluar y comparar los resultados con otros ya publicados del control a largo plazo y evaluar efectividad y efectos colaterales

Primary argon laser trabeculoplasty vs pilocarpine 2% in primary open angle glaucoma: two years follow-up study.

In a prospective study, the efficacy of argon laser trabeculoplasty (ALT) was evaluated and compared with pilocarpine 2% as primary treatment in newly diagnosed primary open angle glaucoma (POAG). Out of 38 patients with POAG included in this study, one eye each of 36 patients underwent ALT, and one eye each of 26 patients received pilocarpine 2% every 8 hours. The mean pre-treatment IOP was 25.48 +/- 4.13 mmHg in ALT group and 24.47 +/- 3.51 mmHg in the pilocarpine group. The mean post treatment IOP at 2 year follow was 18.2 +/- 2.55 mmHg in ALT group and 18.27 +/- 2.22 mmHg in the pilocarpine group. Post treatment IOP was significantly lower than pre-treatment IOP in both ALT and pilocarpine groups. The post treatment fall in IOP showed no significant difference in ALT versus pilocarpine 2% at various follow up intervals (p > 0.05). This study showed equal efficacy of ALT and pilocarpine 2% as initial therapy of POAG.

Relationship between optic nerve head parameters of Heidelberg Retina Tomograph and visual field defects in primary open-angle glaucoma

To investigate the correlation between optic nerve head configuration and visual field defects, optie nerve head analysis using confocal scanning laser tomography (Heidelberg Retina Tomograph, HRT) and automated static threshold perimetry using a Humphrey Field Analyzer (program C3O-2) were performed on 81 eyes of 44 primary open-angle glaucoma (POAG) patients. The optic nerve head parameters-rim area, rim volume, mean retinal nerve fiber layer thickness, height variation contour, and third moment in contour were measured by HRT and were analyzed for correlation with visual field indices-mean deviation, and corrected pattern standard deviation. All optic nerve hend parameters except HVC correlated significantly with the visual field indices; the highest correlation was between rim area and mean deviation (r = 0.6172, p < 0.O0001). The rim area of the superior and inferior quadrants correlated significantly with the visual field defects in corresponding sectors. Structural optic disc measurements by HRT correlated significantly with funetional optic nerve head damage in POAG

Probability of global indices in low tension glaucoma

To know the pattern of visual field (VF) defect of low tension glaucoma (LTG), its diffuse and localized VF defects were compared using the significance values (p-value) of mean deviation (MD) and corrected pattern standard deviation (CPSD), which are calculated with STATPAC in Humphrey Visual Field Analyser. Sixteen eyes of LTG were enrolled and 34 eyes of primary open angle glaucoma (POAG) were used as controls. The degree of VF defects in LTG and POAG was relatively mild with the p-value of MD equal to or greater than 1%. Neither mean MD nor mean CPSD of LTG was significantly different from each of POAG (p > 0.8 and p > 0.2, respectively). Comparing the p-values of MD and CPSD, many patients showed more significant p-value of MD in LTG and POAG (62.5% and 61.8%, respectively). However, relatively more severe defect of CPSD tended to occur more frequently in LTG than in POAG (25% and 5.9%, respectively, chi-square = 4.964, p < 0.09). The relation between p-values of MD and CPSD was not significantly influenced by the intraocular pressure, MD or vertical cup to disc ratio in either LTG or POAG.