In vivo analysis of glaucoma-related features within the optic nerve head using enhanced depth imaging optical coherence tomography.

Structural differences between optic nerve head (ONH) parameters in glaucomatous and non-glaucomatous eyes has been documented, however the association between such parameters in patients with different disease stages is yet to be elucidated. We investigated the relationship between different laminar and prelaminar ONH structures using enhanced depth imaging spectral-domain optical coherence tomography (EDI OCT) in a population with and without glaucoma. In this observational case-control study, we prospectively enrolled healthy individuals and glaucomatous patients with different disease stages. All participants underwent EDI OCT imaging (Heidelberg Engineering). Following ONH parameters were measured on serial vertical B-scans by two examiners masked to patient's clinical data: lamina cribrosa (LC) and prelaminar neural tissue (PLNT) thicknesses, Bruch's membrane opening (BMO) and cup depth. Associations between cup depth, and laminar and prelaminar parameters were evaluated controlling for possible confounding factors such as axial length and disc size. Sixty-four eyes of 64 patients were included (30 with glaucoma and 34 controls). Eyes with glaucoma had significantly lower mean LC and PLNT thickness, and greater mean cup depth than controls (p<0.01). There was a significant negative association between PLNT thickness and cup depth in glaucomatous eyes (R2 = 0.158, p = 0.029). In addition, LC thickness correlated significantly with cup depth (R2 = 0.135, p = 0.045). Eyes with thinner LCs presented deeper cups. Overall, cup depth and BMO had the best and LC thickness had the worst intraobserver and interobserver reproducibility grading. In conclusion, significant associations were seen between cup depth, LC and PLNT thickness. Eyes with deeper cups not only had less neural tissue, but also thinner LCs, independent of disc size and axial length. Best reproducibility was found for prelaminar parameters compared to deeper ONH structures.

Non-pupillary block angle-closure mechanisms: a comprehensive analysis of their prevalence and treatment outcomes / Mecanismos de fechamento angular sem bloqueio pupilar: análise de prevalência e resultados terapêuticos

Purpose: To assess the prevalence and treatment outcomes of angle-closure mechanisms other than pupillary block in a population of Brazilian patients. Methods: A retrospective chart review was conducted to evaluate patients who had undergone laser peripheral iridotomy (LPI) due to occludable angles at a single institution between July 2009 and April 2012. An occludable angle was defined as an eye in which the posterior trabecular meshwork was not visible for ≥180° on dark-room gonioscopy. Key exclusion criteria were any form of secondary glaucoma and the presence of >90° of peripheral anterior synechiae. Collected data were age, race, gender, angle-closure mechanism (based on indentation goniocopy and ultrasound biomicroscopy), intraocular pressure (IOP), number of antiglaucoma medications and subsequent management during follow-up. If both eyes were eligible, the right eye was arbitrarily selected for analysis. Results: A total of 196 eyes of 196 consecutive patients (mean age 58.3 ± 11.6 years) who underwent LPI were included. In most of the patients [86% (169 patients; 133 women and 36 men]), LPI sucessfully opened the angle. Mean IOP was reduced from 18.3 ± 6.4 mmHg to 15.4 ± 4.5 mmHg after LPI (p<0.01). Among the 27 patients with persistent occludable angles, the most common underlying mechanisms were plateau iris (56%) and lens-induced component (34%). Most of these patients (85%) were treated with argon laser peripheral iridoplasty (ALPI); approximately 90% showed non-occludable angles following the laser procedure (mean IOP reduction of 18.9%), with no significant differences between patients with plateau iris and lens-induced components (p=0.34; mean follow-up of 11.4 ± 3.6 months). Conclusion: Our findings suggest that, in this population of Brazilian patients, several eyes with angle closure were not completely treated with LPI. In the present large case series involving middle-age patients, plateau iris was the ...

Objetivo: Reportar a prevalência e os resultados terapêuticos em casos de fechamento angular por outros mecanismos além de bloqueio pupilar em uma população de pacientes brasileiros. Métodos: Realizou-se um estudo retrospectivo para avaliar pacientes apresentando ângulo oclusível submetidos à iridotomia periférica a laser (LPI), em uma única instituição, entre julho/2009 e abril/2012. Ângulo oclusível foi definido pela não observação do trabeculado posterior em mais de 180° à gonioscopia sem identação. Olhos com glaucomas secundários ou >90º de sinéquia anterior periférica foram excluídos. Foram coletados os seguintes dados: idade, raça, sexo, mecanismo de fechamento angular (com base na gonioscopia e biomicroscopia ultrassônica), pressão intraocular (PIO), número de medicações antiglaucomatosas e manejo subsequente durante o seguimento. Sempre que ambos os olhos eram elegíveis, o olho direito foi escolhido arbitrariamente para análise. Resultados: Foram incluídos 196 olhos de 196 pacientes (58,3 ± 11,6 anos) que foram submetidos à LPI. Na maioria dos casos [86% (169 pacientes; 133 mulheres e 36 homens), a LPI foi capaz de abrir o ângulo. A PIO média foi reduzida de 18,3 ± 6,4 para 15,4 ± 4,5 mmHg após a LPI (p<0,01). Entre os 27 casos que persistiram com ângulo oclusível, os mecanismos mais comuns envolvidos foram íris em platô (56%) e induzido por componente cristaliniano (34%). A maioria desses casos (85%) foram tratados com iridoplastia periférica a laser (ALPI). Aproximadamente 90% tornaram-se não oclusíveis após a ALPI (redução média da PIO de 18,9%), não havendo diferença significativa entre os pacientes com componentes de íris em platô ou cristaliniano (p=0,34; seguimento médio de 11,4 ± 3,6 meses). Conclusões: Nossos resultados sugerem que, nessa população de pacientes brasileiros, parte dos olhos com fechamento angular não foi completamente tratada com LPI. Nesta série de pacientes de meia-idade, a presença de íris em ...

Non-pupillary block angle-closure mechanisms: a comprehensive analysis of their prevalence and treatment outcomes.

PURPOSE: To assess the prevalence and treatment outcomes of angle-closure mechanisms other than pupillary block in a population of Brazilian patients. METHODS: A retrospective chart review was conducted to evaluate patients who had undergone laser peripheral iridotomy (LPI) due to occludable angles at a single institution between July 2009 and April 2012. An occludable angle was defined as an eye in which the posterior trabecular meshwork was not visible for ≥180° on dark-room gonioscopy. Key exclusion criteria were any form of secondary glaucoma and the presence of >90° of peripheral anterior synechiae. Collected data were age, race, gender, angle-closure mechanism (based on indentation goniocopy and ultrasound biomicroscopy), intraocular pressure (IOP), number of antiglaucoma medications and subsequent management during follow-up. If both eyes were eligible, the right eye was arbitrarily selected for analysis. RESULTS: A total of 196 eyes of 196 consecutive patients (mean age 58.3 ± 11.6 years) who underwent LPI were included. In most of the patients [86% (169 patients; 133 women and 36 men]), LPI sucessfully opened the angle. Mean IOP was reduced from 18.3 ± 6.4 mmHg to 15.4 ± 4.5 mmHg after LPI (p<0.01). Among the 27 patients with persistent occludable angles, the most common underlying mechanisms were plateau iris (56%) and lens-induced component (34%). Most of these patients (85%) were treated with argon laser peripheral iridoplasty (ALPI); approximately 90% showed non-occludable angles following the laser procedure (mean IOP reduction of 18.9%), with no significant differences between patients with plateau iris and lens-induced components (p=0.34; mean follow-up of 11.4 ± 3.6 months). CONCLUSION: Our findings suggest that, in this population of Brazilian patients, several eyes with angle closure were not completely treated with LPI. In the present large case series involving middle-age patients, plateau iris was the leading cause of persistent angle closure and was effectively treated with ALPI. A detailed eye examination with indentation gonioscopy should always be performed after LPI to rule out persistent angle closure due to non-pupillary block mechanisms.