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.

Central visual function and inner retinal structure in primary open-angle glaucoma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

To investigate associations between central visual function and inner retinal structure in primary open-angle glaucoma (POAG). This study enrolled 78 POAG patients and 58 healthy controls. POAG was classified into early glaucoma and moderate to advanced glaucoma. The following tests were performed on all participants: isolated-check visual evoked potential (icVEP) testing, 24-2 standard automated perimetry (SAP), and Cirrus optical coherence tomography (OCT) examinations. Signal-to-noise ratio (SNR) measures obtained from icVEP responses to isolated checks presented at four depths of modulation (DOMs; 8%, 14%, 22%, and 32%) were explored. Mean macular sensitivity (mMS) was assessed by calculating the mean sensitivities of central 12 SAP points. Ganglion cell layer+ inner plexiform layer thickness (GCL+IPLT) and peripapillary retinal nerve fiber layer thickness (pRNFLT) were measured by OCT scanning. For each group of subjects, linear relationships among the following measures were analyzed: SNR, mMS, GCL+IPLT, and pRNFLT. SNR, mMS, GCL+IPLT, and pRNFLT were all more significantly decreased in glaucoma than in controls (P<0.001). A significant positive association was found between SNR at 14% DOM and GCL+IPLT at the inferior sector in early glaucoma (r=0.465, P=0.004). In moderate to advanced glaucoma, significant correlations were found between SNR at 32% DOM and mean GCL+IPLT (r=0.364, P=0.023), superior GCL+IPLT (r=0.358, P=0.025), and mean pRNFLT (r=0.396, P=0.025). In addition, in moderate to advanced glaucoma, there were significant correlations between mMS and all relevant measures of retinal thickness (r=0.330-0.663, P< 0.010). In early glaucoma, significant correlations were found between mean mMS and minimum GCL+IPLT (r=0.373, P=0.023), and between inferior mMS and superior GCL+IPLT (r=0.470, P=0.003). Linear models provided a good explanation for the relationship between SNR and inner retinal thickness (IRT), whereas nonlinear models better explained the relationship between mMS and IRT. In early glaucoma, both SNR and mMS were related moderately and significantly to IRT, whereas in moderate to advanced glaucoma, mMS was more strongly correlated with IRT than SNR.

Lack of association between provocative test-based intraocular pressure parameters and functional loss in treated glaucoma patients / Falta de associação entre parâmetros de pressão intraocular obtidos pelo teste de sobrecarga hídrica e dano funcional em pacientes com glaucoma

ABSTRACT Purpose: To correlate provocative test-based intraocular pressure (IOP) variation parameters (fluctuation and peak) with functional status, and to compare these IOP parameters between treated eyes with asymmetric primary open-angle glaucoma (POAG). Methods: A prospective observational study including consecutively treated patients with primary open-angle glaucoma was performed. Subjects with ocular diseases other than glaucoma or previous incisional glaucoma surgery were excluded. The primary inclusion criteria were 33 visual field tests and 32 years of follow-up, without any changes on current medical regimen. Long-term intraocular pressure parameters were acquired via isolated intraocular pressure measurements from the patients' last 5 office visits. To evaluate provocative test-based intraocular pressure parameters, all patients were submitted to a water drinking test. Initially, the partial correlation coefficients between each intraocular pressure variation parameter and visual field mean deviation were calculated, adjusting for the baseline intraocular pressure and number of antiglaucoma medications. In addition, each intraocular pressure parameter was compared between eyes with better visual field mean deviation and fellow eyes with worse visual field mean deviation in patients with asymmetric visual field loss (defined as an inter-eye visual field mean deviation difference of at least 3 dB). Results: A total of 87 eyes (87 patients; mean age, 61.9 ± 12.5 years; 59.8% women) with primary open-angle glaucoma were included. The patients underwent a median of 5 visual field tests, with a mean follow-up of 4.3 ± 1.4 years. Neither long-term nor water-drinking test intraocular pressure variation parameters were significantly associated with visual field mean deviation values (p30.117). In the subgroup with asymmetric visual field loss (64 eyes of 32 patients; mean age, 65.0 ± 11.4 years), neither long-term water-drinking test intraocular pressure variation parameters differed significantly between eyes with better and worse visual field mean deviation (p30.400). Conclusion: Our results indicate that neither long-term intraocular pressure variation parameters nor stress test-derived intraocular pressure metrics, as assessed by the water-drinking test, appear to correlate with the visual field status or differ significantly between eyes with asymmetric visual field damage, suggesting that other factors may explain such functional asymmetry, and that the water-drinking test does not add significant information to these cases.

RESUMO Objetivo: Correlacionar os parâmetros de variação da pressão intraocular (flutuação e pico) com o dano funcional em pacientes tratados com glaucoma primário de ângulo aberto, e comparar esses parâmetros de pressão intraocular entre olhos com dano funcional assimétrico. Métodos: Estudo observacio nal prospectivo foi realizado incluindo consecutivamente pa cientes tratados com glaucoma primário de ângulo aberto. Foram excluídos indivíduos com outras doenças oculares que não o glaucoma ou cirurgia prévia incisional de glaucoma. Os principais critérios de inclusão foram: 33 testes de campo visual e 32 anos de acompanhamento, sem quaisquer alterações no regime medicamentoso atual. Parâmetros de pressão intraocular de longo prazo foram obtidos através de medidas de pressão intraocular isoladas de cada consulta (as últimas 5 consultas de cada paciente foram consideradas para análise). Para avaliação dos parâmetros de pressão intraocular de curto prazo, todos os pacientes foram submetidos ao teste de sobrecarga hídrica. Ini cialmente, calculamos os coeficientes de correlação parcial de cada parâmetro de variação da pressão intraocular com o nível de dano funcional, baseado no índice Mean Deviation (MD), ajustando para a pressão intraocular basal e o número de medicações antiglaucomatosas. Além disso, comparamos cada parâmetro de pressão intraocular entre os olhos com melhor e pior nível de dano funcional em pacientes com perda de campo visual assimétrica (definida como diferença no índice mean deviation entre os olhos de pelo menos 3 dB). Resultados: Foram incluídos 87 olhos (87 pacientes) com glaucoma primário de ângulo aberto. A idade média foi de 61,9 ± 12,5 anos e 59,8% eram mulheres. Em geral, os pacientes foram submetidos a 5 testes (mediana) de campo visual, com um seguimento médio de 4,3 ± 1,4 anos. Nem os parâmetros de variação da pressão intraocular de longo prazo nem aqueles obtidos pelo teste de sobrecarga hídrica se correlacionaram significativamente com o nível de dano no campo visual (p30,117). No subgrupo com perda de campo visual assimétrica (64 olhos de 32 pacientes; idade média, 65,0 ± 11,4 anos), nem os parâmetros de variação da pressão intraocular de longo prazo nem os obtidos pelo teste de sobrecarga hídrica diferiram significativamente entre olhos com melhor e pior nível de dano funcional (p3 0,400). Conclusão: Nossos resultados indicam que não apenas parâmetros de variação da pressão intraocular de longo prazo, mas também medidas de pressão intraocular derivadas do teste de sobrecarga hídrica, não parecem se correlacionar com o nível de dano do campo visual, nem diferem significativamente entre olhos com nível de dano funcional assimétrico. Esses achados sugerem que outros fatores poderiam explicar essa assimetria funcional e que o teste de sobrecarga hídrica não acrescenta informações significativas a esses casos.

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)

Intraocular pressure fluctuation in healthy and glaucomatous eyes: a comparative analysis between diurnal curves in supine and sitting positions and the water drinking test / Flutuação da pressão intraocular em olhos saudáveis e olhos glaucomatosos: análise comparativa entre a curva tensional diária simplificada nas posições sentada, supina e o teste de sobrecarga hídrica

Purpose: To compare intraocular pressure (IOP) using the simplified daily tensional curve (SDTC) between supine and sitting positions in terms of peak levels and amount of fluctuation in both, glaucomatous and healthy subjects. The secondary endpoint was the comparison of these measures with those derived from the water drinking test (WDT). Methods: Thirty patients with primary open-angle glaucoma (POAG) that were undergoing medical therapy and 30 healthy subjects were enrolled in this study. Each patient underwent a diurnal curve between 8 am and 4 pm. After lying down for 5 minutes, the IOP was measured with the Perkins tonometer. Patients were instructed to sit in the upright position for 5 minutes and the tonometry was repeated. At 4:15 pm, the WDT test was performed. Fluctuation was defined as the difference between the highest and the lowest IOP readings (range). The Student's t test was used to assess differences and a P value <0.05 was considered to be statistically significant. Results: The diurnal curve in the supine position demonstrated higher IOP average values (on average 3-4 mmHg higher) compared to the sitting position (p<0.0001) for both groups. IOP peaks were higher in the supine position; however, the IOP range was essentially the same between the three methods. Treated glaucomatous patients had higher IOP levels in all measurements, but the fluctuation for all tests performed appeared to be similar to that of healthy patients. Conclusion: The data suggested that WDT can be used to estimate the diurnal IOP peak and fluctuation observed in the SDTC of the supine position for treated glaucomatous patients. Further studies can compare the possible correlation between the WDT results and those obtained from nocturnal supine measurements. .

Objetivo: Comparar a flutuação da pressão intraocular (PIO) nas posições sentada e supina, através da curva tensional diária simplificada (CTDS), durante o horário de consultório em pacientes saudáveis e com glaucoma primário de ângulo aberto (GPAA). O objetivo secundário foi comparar estas medidas com a flutuação da PIO verificada através do teste de sobrecarga hídrica (TSH) desses dois grupos. Métodos: A amostra foi constituída por 60 indivíduos, divididos em dois grupos, 30 saudáveis e 30 glaucomatosos. Nenhum dos pacientes saudáveis usava medicação anti-glaucomatosa. Entre os portadores de glaucoma, todos estavam medicados. Foi realizada a CTDS (medidas realizadas entre 8:00 h e às 16:00 h) na posição sentada e supina utilizando o mesmo tonômetro de Perkins. Imediatamente após a última medida (às 16:15 h), foi realizado o TSH. Flutuação foi definida como a diferença entre a maior e a menor medida de PIO. O teste t-Student foi usado para analisar as diferenças e o valor de p<0,05 foi considerado estatisticamente significante. Resultados: Os picos de PIO foram sempre maiores na CTDS quando medidos na posição supina (em média 4 mmHg maior) em pacientes saudáveis e pacientes glaucomatosos em tratamento, comparado a posição sentada (p<0.0001). Pacientes glaucomatosos em tratamento apresentaram PIO mais alta em todas as medidas, porém a flutuação em todos os testes realizados foi semelhante comparada aos pacientes saudáveis. A flutuação da PIO não apresentou diferença estatística entre os 3 métodos. Conclusão: Dados sugerem que o TSH pode ser usado para estimar o pico e a flutuação diurna da PIO na posição supina na CTDS em pacientes glaucomatosos em ...

Depth and Area of Retinal Nerve Fiber Layer Damage and Visual Field Correlation Analysis

PURPOSE: To evaluate the relationship between the structural damage as assessed by time-domain optical coherence tomography (OCT) and functional changes in glaucoma. METHODS: In total, 190 patients with normal tension glaucoma or primary open angle glaucoma were included in this study. The thickness of retinal nerve fiber layer (RNFL) around the optic disc and the area of RNFL defect were determined using OCT scans. The relationships between the RNFL thickness or area of the defect and visual field (VF) indices were assessed using the Lowess function, regression analysis and partial Spearman correlation. The differences between these associations depending on the stage of VF damage were further analyzed. Age, optic disc size, refraction, central corneal thickness and the presence of systemic disease were corrected for in order to exclude confounding factors. RESULTS: A logarithmic scale of RNFL thickness showed a negative linear relationship with VF indices. The area of the RNFL defect showed a weak correlation with the pattern of standard deviation, whereas the remnant RNFL thickness was moderately correlated with the pattern of standard deviation (partial Spearman correlation coefficient, 0.39, -0.47, respectively; p < 0.0001). Many outliers were detected in the Lowess-plotted graphs. Multiplication of the area and the inverted RNFL thickness showed a moderately correlated logarithmic relationship with the VF indices (partial Spearman correlation coefficient, 0.46; 95% confidence interval, 0.34 to 0.57; p < 0.0001). In the severe stage of VF damage, correlation between the area of the RNFL defect and mean deviation was significantly greater than in other stages (partial Spearman correlation coefficient, -0.66; p = 0.02). CONCLUSIONS: The thickness of the RNFL had a negative logarithmic correlation with the VF indices and was more relevant to the VF indices than the area of the RNFL defect, as measured by OCT.

Idiopathic dilated episcleral vessels (Radius-Maumenee syndrome): case report / Dilatação idiopática dos vasos episclerais (síndrome de Radius-Maumenee): relato de caso

Radius-Maumenee syndrome comprises idiopathic dilated episcleral vessels that are usually associated with glaucoma. The case described herein is of a male patient, 69 years old, with chronic dilation of the episcleral vessels and glaucoma in his left eye, with no history of systemic disease. Visual acuity and fundoscopy were normal in both eyes. Tonometry measured 14 mmHg in the right eye and 25 mmHg in the left. Computed tomography angiography (CTA) was negative for carotid-cavernous fistula. The intraocular pressure of the left eye decreased to 20 mmHg with clinical treatment without regression of episcleral venous dilation. Trabeculectomy normalized the intraocular pressure and reduced the vessels. There was choroidal effusion on day 16 of the postoperative period, which resolved with corticosteroids. Although choroidal effusion can occur, the efficacy of trabeculectomy in controlling glaucoma and the reduction of episcleral vessels are clearly demonstrated.

A síndrome de Radius-Maumenee consiste na dilatação idiopática dos vasos episclerais geralmente associada ao glaucoma. Descreve-se o caso de paciente masculino, 69 anos, portador de dilatação crônica dos vasos episclerais e glaucoma do olho esquerdo, sem histórico de doença sistêmica. A acuidade visual e fundoscopia apresentaram-se normais em ambos os olhos. A tonometria mediu 14 mmHg no olho direito e 25 mmHg no esquerdo. A angiotomografia foi negativa para fístula carotídeo-cavernosa. A pressão intraocular do olho esquerdo diminuiu para 20 mmHg com tratamento clínico, sem regressão da dilatação venosa episcleral. A trabeculectomia normalizou a pressão intraocular e reduziu os vasos. Houve efusão coroidiana no 16º dia de pós-operatório que regrediu com corticoterapia. Embora possa ocorrer efusão coroidiana, destaca-se a eficácia da trabeculectomia no controle do glaucoma e na redução dos vasos episclerais.

Long-term Results of Deep Sclerectomy with Small Collagen Implant in Korean

PURPOSE: To describe the long-term results of deep sclerectomy with collagen implant (DSCI) with or without adjuvant mitomycin C in Korean patients with primary or secondary open-angle glaucoma (OAG). METHODS: This retrospective review was comprised of 65 Korean patients who received DSCI with or without adjuvant mitomycin C due to primary or secondary OAG. Patients were followed for 72 months after surgery. Complete success was defined as intraocular pressure (IOP) <21 mmHg without medication and qualified success was defined as IOP <21 mmHg with or without medication. RESULTS: Mean postoperative follow-up period was 53.0 +/- 16.2 months. Mean IOP was 30.5 +/- 11.7 mmHg preoperatively, 8.4 +/- 4.3 mmHg at postoperative day one and 13.4 +/- 3.8 mmHg 60 months after surgery. The mean number of glaucoma medications was decreased from 3.6 +/- 1.1 to 1.6 +/- 1.3 at 60 months after the operation. Complete and qualified success rates were 36.7% and 79.6% at postoperative 60 months, respectively (Kaplan-Meier survival curve). No shallow or flat anterior chamber, endophthalmitis, or surgery-induced significant cataract was observed. CONCLUSIONS: The results of DSCI in Korean patients presented here seem reasonably excellent with qualified success rates of over 70% at six years with negligible complications.

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.

Nerve fiber layer in glaucomatous hemifield loss: a case-control study with time- and spectral-domain optical coherence tomography / Camada de fibras nervosas na perda de hemicampo glaucomatoso: um estudo caso-controle com tomografia de coerência óptica time- e spectral-domain

PURPOSE: To evaluate the retinal nerve fiber layer measurements with time-domain (TD) and spectral-domain (SD) optical coherence tomography (OCT), and to test the diagnostic ability of both technologies in glaucomatous patients with asymmetric visual hemifield loss. METHODS: 36 patients with primary open-angle glaucoma with visual field loss in one hemifield (affected) and absent loss in the other (non-affected), and 36 age-matched healthy controls had the study eye imaged with Stratus-OCT (Carl Zeiss Meditec Inc., Dublin, California, USA) and 3 D OCT-1000 (Topcon, Tokyo, Japan). Peripapillary retinal nerve fiber layer measurements and normative classification were recorded. Total deviation values were averaged in each hemifield (hemifield mean deviation) for each subject. Visual field and retinal nerve fiber layer "asymmetry indexes" were calculated as the ratio between affected versus non-affected hemifields and corresponding hemiretinas. RESULTS: Retinal nerve fiber layer measurements in non-affected hemifields (mean [SD] 87.0 [17.1] µm and 84.3 [20.2] µm, for TD and SD-OCT, respectively) were thinner than in controls (119.0 [12.2] µm and 117.0 [17.7] µm, P<0.001). The optical coherence tomography normative database classified 42% and 67% of hemiretinas corresponding to non-affected hemifields as abnormal in TD and SD-OCT, respectively (P=0.01). Retinal nerve fiber layer measurements were consistently thicker with TD compared to SD-OCT. Retinal nerve fiber layer thickness asymmetry index was similar in TD (0.76 [0.17]) and SD-OCT (0.79 [0.12]) and significantly greater than the visual field asymmetry index (0.36 [0.20], P<0.001). CONCLUSIONS: Normal hemifields of glaucoma patients had thinner retinal nerve fiber layer than healthy eyes, as measured by TD and SD-OCT. Retinal nerve fiber layer measurements were thicker with TD than SD-OCT. SD-OCT detected abnormal retinal nerve fiber layer thickness more often than TD-OCT.

OBJETIVO: Avaliar as medidas da camada de fibras nervosas da retina com a tomografia de coerência óptica (OCT) "time domain" (TD) e "spectral domain" (SD), e testar a habilidade diagnóstica de ambas as tecnologias em pacientes com perda assimétrica glaucomatosa de hemicampo visual. MÉTODOS: Trinta e seis pacientes com glaucoma primário de ângulo aberto com perda de campo visual em um hemicampo (acometido) e ausência de perda no hemicampo oposto (não-acometido), e 36 controles pareados por idade tiveram o olho de estudo examinado com Stratus-OCT (Carl Zeiss Meditec Inc., Dublin, California, USA) e 3 D OCT-1000 (Topcon, Tokyo, Japan). As medidas de espessura da camada de fibras nervosas da retina peripapilar e classificação normativa fornecida pelos aparelhos foram registrados para análise. A média aritmética dos valores do gráfico de desvio total em cada hemicampo foi calculada para cada indivíduo. "Índices de assimetria" para campo visual e camada de fibras nervosas da retina foram calculados como a razão entre hemicampos acometido e não-acometido e hemirretinas correspondentes, respectivamente. RESULTADOS: As medidas da camada de fibras nervosas da retina em hemicampos não-acometidos (média [SD] 87.0 [17.1] µm e 84.3 [20.2] µm, para TD e SD-OCT, respectivamente) foram menores do que em controles (119.0 [12.2] µm e 117.0 [17.7] µm, P<0.001). O banco de dados normativo classificou como alterado 42% e 67% das hemirretinas correspondentes a hemicampos não-acometidos com TD e SD-OCT, respectivamente (P=0.01). As medidas da camada de fibras nervosas da retina foram consistentemente mais espessas com TD comparados com SD-OCT. Índices de assimetria da camada de fibras nervosas da retina foram semelhantes entre TD (0.76 [0.17]) e SD-OCT (0.79 [0.12]) e significantemente maiores do que o índice de assimetria do campo visual (0.36 [0.20], P<0.001). CONCLUSÃO: Os hemicampos normais de pacientes com glaucoma apresentaram camada de fibras nervosas da retina mais fina do que olhos saudáveis. As medidas da camada de fibras nervosas da retina foram mais espessas com TD do que com SD-OCT, que por sua vez detectou anormalidades na espessura da camada de fibras nervosas da retina mais frequentemente do que o TD-OCT.

HLA class I haplotypes and progression of primary open-angle glaucoma / Haplotipos HLA de classe I e progressão do glaucoma primário de ângulo aberto

PURPOSE: To verify if patients with primary open-angle glaucoma with HLA class I haplotypes (A9-B12, A2-B40, A1-B8) associated with this disease may have a greater rate of progression than patients who do not present these haplotypes. METHODS: Anatomical and functional glaucoma evaluation (cup-to-disc ratio and visual field) of 25 patients (six of them with one of the haplotypes associated with glaucoma) followed at the Glaucoma Outpatient Clinic of the University Hospital, Ribeirão Preto School of Medicine, São Paulo University (HCFMRP-USP) for ten years after typing of their HLA antigens in order to compare with their previous condition. RESULTS: A greater increase of the cup-to-disc ratio was observed in patients with HLA haplotypes associated with primary open-angle glaucoma predisposition. However, no significant differences in functional damage progression or in retinal nerve fibers loss were detected between them and other patients with glaucoma. CONCLUSION: The present results indicate an association of class I HLA haplotypes with progression of anatomic alterations of the optic nerve head in glaucomatous patients.

OBJETIVO: Verificar se pacientes com glaucoma primário de ângulo aberto portadores de haplotipos HLA de classe I (HLA - A9-B12; -A2-B40; e -A1-B8) associados a essa doença poderiam ter progressão maior do que pacientes que não apresentassem esses haplotipos. Método: Avaliação anatômica e funcional de 25 pacientes (6 dos quais com um dos haplotipos associados a glaucoma), seguidos no Ambulatório de Glaucoma do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP), por dez anos depois da tipificação de seus antígenos HLA, para comparação com as condições anteriores. RESULTADOS: Houve aumento maior da relação escavação/disco em pacientes com haplotipos HLA associados com predisposição para glaucoma primário de ângulo aberto, no entanto não foram encontradas diferenças significantes entre esses e outros pacientes com glaucoma na progressão do dano fisiológico e nem na perda de fibras nervosas da retina. CONCLUSÃO: Os resultados indicam a associação de haplotipos HLA de classe I com maior taxa de progressão das alterações anatômicas da cabeça nervo óptico em pacientes com glaucoma.

Dilated episcleral veins with secondary open angle glaucoma.

We report a case of dilated episcleral vein with secondary open angle glaucoma. A 65-year-old female presented with redness of both the eyes without any prior systemic history. Her ocular examination revealed dilated episcleral veins and a high intraocular pressure (IOP) of 38 mm Hg in the right eye. Systemic examination was negative for carotid cavernous fistula, low-grade dural arteriovenous fistula, dysthyroid ophthalmopathy, and primary pulmonary hypertension. During follow-up, her IOP remained in high thirties despite maximum medications. She underwent right eye trabeculectomy with partial thickness sclerectomy with sclerotomy. In the beginning, the sclerotomy incision was not deepened into the suprachoroidal space. She developed choroidal effusion during surgery and the sclerotomy was deepened into suprachoroidal space and straw color fluid was drained. Postoperatively, she developed choroidal effusion, which resolved with conservative management. This case highlights the importance of sclerotomy in such cases of high episcleral venous pressure.

Lasers in primary open angle glaucoma.

Lasers have been used in the treatment of primary open angle glaucoma (POAG) over the years, with the hope that they would eventually replace medical and surgical therapy. Laser trabeculoplasty (LT) is an application of argon, diode, or selective laser energy to the surface of the trabecular meshwork to increase the aqueous outflow. The mechanisms by which intraocular pressure (IOP) is lowered could be mechanical, biologic, or by division of adjacent cells. It is commonly used as an adjunct to medical therapy, but is contraindicated if the angle is obstructed, e.g., peripheral anterior synechia (PAS) or developmental glaucomas. About 75% of individuals will show a significant fall in IOP after argon laser trabeculoplasty (ALT), and the response is similar with selective laser trabeculoplasty (SLT). The effects of LT are not always long lasting, with about 10% of individuals showing a rise in IOP with every passing year. Laser thermal sclerostomy, ab interno or externo, is an alternative to other full-thickness filtration procedures. Longer wavelengths in the infrared range have water-absorptive characteristics that facilitate perforation of the sclera. These lasers can be used to avoid intraocular instrumentation and minimize conjunctival trauma.

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.

Correlation between central corneal thickness and intraocular pressure peak and fluctuation during the water drinking test in glaucoma patients

OBJECTIVE: To investigate the correlation between central corneal thickness and outflow facility assessed by intraocular pressure peak and fluctuation during the water drinking test. METHODS: Fifty-five newly diagnosed primary open-angle glaucoma patients submitted to central corneal thickness measurements and water drinking test were enrolled in this retrospective study.;. Patients were divided into three groups according to their central corneal thickness. Pearson's Correlation test was performed in the groups with lower and higher pachymetric values. RESULTS: The mean age was 65,65 ± 28,28 years; 63,63 percent were female and 52,72 percent were caucasian. The mean central corneal thickness was 544,32 ± 36,86 µm, and the mean baseline intraocular pressure was 23,36 ± 6,26 mmHg. During the water drinking test, the mean intraocular pressure peak and mean intraocular pressure fluctuation were 30,43 ± 8,13 mmHg and 31,46 ± 18,46 percent, respectively. No relevant correlation was detected between the central corneal thickness and the intraocular pressure peak (r² = 0,021) or between the central corneal thickness and the intraocular pressure fluctuation (r² = 0,011). Group 1 presented a mean central corneal thickness of 505,81 ± 13,86 µm, and Group 3 was 583,55 ± 27,87 µm (p = 0,001). The mean intraocular pressure peak was 31,05 ± 9,05 mmHg and 27,83 ± 4,92 mmHg in Group 1 and in Group 3, respectively (p = 0,193). The difference of intraocular pressure fluctuation was not statistically significant between Group 1 (mean 28,47±16,25 percent) and Group3 (mean 33,27 ± 21,27 percent) (p = 0,43). CONCLUSION: In our case series, no correlation was found between central corneal thickness and water drinkingtest results.

Reproducibility of water drinking test performed at different times of the day / Reprodutibilidade do teste de sobrecarga hídrica realizado em diferentes horários do dia

PURPOSE: To evaluate the reproducibility of water drinking test (WDT) performed at different times of the day, in primary open angle glaucoma (POAG) patients and normal individuals. METHODS: Fifteen patients with POAG and 30 normal individuals underwent three WDTs at different times of the day (7 AM, 12 PM, and 5 PM) on 3 different days. Test results in POAG patients and normal individuals were compared. Agreement and correlation of intraocular pressure (IOP) baseline levels, peak levels, and IOP change (peak IOP - baseline IOP) on tests performed at different times were evaluated. Only right eye measurements were analyzed. RESULTS: Mean baseline IOP, peak IOP and IOP change were significantly higher in POAG patients than in normal individuals, at all time intervals (p<0.05). The Bland-Altman analysis demonstrated limits of agreement for IOP peak levels and IOP changes larger than the clinically acceptable (>3 mmHg), even though Pearson's test revealed good correlation among the results. CONCLUSION: The mean IOP peak and mean IOP change observed during WDT are significantly higher in POAG patients than in control individuals. Low levels of agreement among WDTs performed at different times of the day suggest a poor reproducibility of WDT, which may limit its applicability for the diagnosis and follow-up of glaucoma.

OBJETIVO: Avaliar a reprodutibilidade do teste de sobrecarga hídrica (TSH) em diferentes horários em que é realizado, em pacientes com glaucoma primário de ângulo aberto (GPAA) e em indivíduos normais. MÉTODOS: Quinze pacientes com GPAA e 30 indivíduos normais foram submetidos a três TSHs, realizados em diferentes horários do dia (às 7:00 h, 12:00 h e 17:00 h), em três dias diferentes. Foram comparados os resultados dos testes em pacientes com GPAA e indivíduos normais. Foram analisadas a concordância e a correlação entre os valores de medida basal, pico e variação de pressão intraocular (PIO) (pico de PIO - PIO basal) nos testes realizados nos diferentes horários. Apenas as medidas do olho direito foram analisadas. RESULTADOS: Os valores médios de medida basal, pico e variação de PIO foram significativamente maiores nos pacientes glaucomatosos que nos indivíduos normais, em todos os horários (p<0,05). A análise de Bland-Altman apresentou limites de concordância de pico e variação de PIO maiores do que o clinicamente aceitável (>3 mmHg), apesar de o teste de Pearson demonstrar boa correlação entre os resultados. CONCLUSÃO: O TSH apresenta valores de pico e variações da PIO significativamente maiores em pacientes glaucomatosos que em indivíduos normais. Os baixos níveis de concordância entre os TSHs realizados em diferentes horários do dia sugerem uma baixa reprodutibilidade do TSH, que pode limitar sua aplicabilidade para diagnóstico e acompanhamento do glaucoma.

Correlation between diurnal variation of intraocular pressure, ocular pulse amplitude and corneal structural properties / Correlação entre a variação diurna da pressão intraocular, amplitude de pulso e propriedades estruturais corneanas

PURPOSE: The purpose of this study was to evaluate the fluctuation of intraocular pressure measurements obtained by Goldmann applanation tonometry, dynamic contour tonometry, and corneal compensated non-contact tonometry during office hours in glaucoma and healthy participants. This study also aims at correlating the intraocular pressure fluctuations with fluctuations of corneal hysteresis, central corneal thickness, mean central corneal curvature and ocular pulse amplitude. METHODS: A total of 12 controls (24 eyes) and 21 patients (38 eyes) with open-angle glaucoma were recruited. Intraocular pressure measured by Goldmann applanation tonometry, dynamic contour tonometry and corneal compensated non-contact tonometry, ocular pulse amplitude, central corneal curvature and thickness, corneal hysteresis, and resistance factor were obtained at intervals of 2 hours, between 9 AM and 5 PM. RESULTS: Intraocular pressure fluctuated significantly throughout the day in controls and glaucoma individuals with all tonometers (P<0.001). There was no statistically significant variation in mean corneal curvature (P=0.048 in controls; P=0.04 in glaucomatous) or hysteresis over time (P=0.12 in controls; P=0.36 in glaucomatous). The ocular pulse amplitude showed a significant diurnal fluctuation in both groups (P<0.001). There was a significant correlation between the intraocular pressure measured by dynamic contour tonometry and ocular pulse amplitude (P<0.001). CONCLUSION: There was significant intraocular pressure fluctuation over office hours on measurements performed by Goldmann applanation tonometry, dynamic contour tonometry, and corneal compensated non-contact tonometry in normal and glaucoma individuals. Intraocular pressure varied independently of corneal hysteresis, central corneal thickness, and central curvature variation. However, there was significant correlation between ocular pulse amplitude and intraocular pressure measurements performed ...

OBJETIVO: Avaliar a flutuação das medidas da pressão intraocular obtidas pela tonometria de aplanação de Goldmann, tonometria de contorno dinâmico e pela tonometria de não-contato com compensação corneana durante o período ambulatorial, em participantes com glaucoma e saudáveis. Esse estudo também correlacionou as flutuações da pressão intraocular com as flutuações da histerese corneana, espessura corneana central, média da curvatura corneana central e amplitude de pulso ocular. MÉTODOS: Um total de 12 controles (24 olhos) e 21 pacientes com glaucoma de ângulo aberto (38 olhos) foram selecionados. A pressão intraocular medida pela tonometria de aplanação de Goldmann, tonometria de contorno dinâmico e tonometria de não-contato com compensação corneana, amplitude de pulso ocular, a curvatura central e espessura corneanas, a histerese corneana e o fator de resistência foram medidos em intervalos de 2 horas, entre 9 AM e 5 PM. RESULTADOS: A pressão intraocular flutuou significativamente durante o dia em indivíduos controles e com glaucoma em todos os tonômetros (P<0,001). Não houve variação estatisticamente significante na média da curvatura corneana central (P=0,048 em controles; P=0,04 em glaucomatosos) ou na histerese no período pesquisado (P=0,12 em controles; P=0,36 em glaucomatosos). A amplitude de pulso ocular mostrou uma flutuação diurna significativa em ambos os grupos (P<0,001). Houve uma correlação significante entre a pressão intraocular medida pela tonometria de contorno dinâmico e a amplitude de pulso ocular (P<0,001). CONCLUSÃO: Houve uma flutuação significante da pressão intraocular ao longo do período ambulatorial nas medidas realizadas pela tonometria de aplanação de Goldmann, tonometria de contorno dinâmico, e tonometria de não-contato com compensação corneana em indivíduos normais e com glaucoma. A pressão intraocular variou independente da variação da histerese, espessura e curvatura central corneanas. Entretanto, houve ...