Jayme R. Vianna

Importance of Normal Aging in Estimating the Rate of Glaucomatous Neuroretinal Rim and Retinal Nerve Fiber Layer Loss

PURPOSE To describe longitudinal rates of change of neuroretinal parameters in patients with glaucoma and healthy controls, and to evaluate the influence of covariates. DESIGN Prospective longitudinal study. PARTICIPANTS Treated patients with glaucoma (n = 192) and healthy controls (n = 37). METHODS Global disc margin-based neuroretinal rim area (DMRA) was measured with confocal scanning laser tomography, while Bruchs membrane opening-minimum rim width (BMO-MRW), BMO area (BMOA), and peripapillary retinal nerve fiber layer thickness (RNFLT) were measured with optical coherence tomography at 6-month intervals. Individual rates of change were estimated with ordinary least-squares regression, and linear mixed effects modeling was used to estimate the average rate of change and differences between the groups, and to evaluate the effects of baseline measurement and baseline age on rates of change. MAIN OUTCOME MEASURES Rates of change for each parameter. RESULTS Subjects were followed for a median (range) of 4 (2-6) years. The proportion of controls who had significant reduction of neuroretinal parameters was 35% for BMO-MRW, 31% for RNFLT, and 11% for DMRA. The corresponding figures for patients with glaucoma were not statistically different (42%, P = 0.45; 31%, P = 0.99; 14%, P = 0.99, respectively). Controls had a significant reduction of BMO-MRW (mean: -1.92 μm/year, P < 0.01) and RNFLT (mean: -0.44 μm/year, P = 0.01), but not DMRA (mean: -0.22×10(-2) mm(2)/year, P = 0.41). After adjusting for covariates, patients with glaucoma had faster, but not statistically different, rates of deterioration compared with controls, by -1.26 μm/year (P = 0.07) for BMO-MRW, -0.40 μm/year (P = 0.11) for RNFLT, and -0.38×10(-2) mm(2)/year (P = 0.23) for DMRA. Baseline BMO-MRW and RNFLT significantly influenced the respective rates of change, with higher baseline values relating to faster reductions. Older age at baseline was associated with a slower reduction in rates of BMO-MRW. Reductions in intraocular pressure were related to increases in BMO-MRW and DMRA. There was a tendency for BMOA to decrease over time (-0.38×10(-2) mm(2)/year; P = 0.04). CONCLUSIONS Age-related loss of neuroretinal parameters may explain a large proportion of the deterioration observed in treated patients with glaucoma and should be carefully considered in estimating rates of change.

Beta and Gamma Peripapillary Atrophy in Myopic Eyes With and Without Glaucoma

PURPOSE To determine whether beta and gamma peripapillary atrophy (PPA) areas measured with optical coherence tomography (OCT) enhances glaucoma diagnosis in myopic subjects. METHODS We included 55 myopic glaucoma patients and 74 myopic nonglaucomatous controls. Beta-PPA comprised the area external to the clinical disc margin, with absence of retinal pigment epithelium and presence of Bruchs membrane. Gamma-PPA comprised the area external to the disc margin, with absence of both RPE and Bruchs membrane. OCT scans colocalized to fundus photographs were used to measure PPA, choroidal thickness, border tissue of Elschnig configuration, optic disc area, and optic disc ovality. RESULTS Beta-PPA area was larger in glaucoma patients compared with controls (median [interquartile range], 1.0 [0.66-1.53] mm2 and 0.74 [0.50-1.38] mm2, respectively), whereas gamma-PPA was smaller in glaucoma patients compared with controls (0.28 [0.14-0.50] mm2 and 0.42 [0.17-0.74] mm2, respectively). However, the distributions of both beta- and gamma-PPA in the two groups overlapped widely. The areas under the receiver operating characteristic curve of beta- and gamma-PPA areas were 0.60 and 0.59, respectively. Larger beta-PPA area was associated with larger disc area, thinner choroidal thickness, longer axial length, less oblique border tissue configuration, older age, and greater disc ovality. Larger gamma-PPA area was associated with greater disc ovality, more oblique border tissue configuration, and longer axial length. CONCLUSIONS Subclassifying PPA with OCT into beta and gamma zones reveals association with different covariates, but does not enhance the diagnostic performance for glaucoma in a population of predominantly Caucasians myopic subjects.

How to detect progression in glaucoma.

Detecting glaucoma progression remains one of the most challenging aspects of glaucoma management, since it can be hard to distinguish disease progression from exam variability and changes due to aging. In this review article, we discuss the use of perimetry, confocal scanning laser tomography and optical coherence tomography to detect glaucoma progression, and the techniques available to evaluate change with these modalities. Currently, there is no consensus on the best technique or criteria to detect glaucoma progression, or what amount of change would be clinically meaningful. New techniques have been developed to assess glaucoma progression, which make more comprehensive and complex use of data. They have the potential of detecting progression with better accuracy, with shorter follow-up periods, and generating better prognostics. Further validation of these new techniques is still required, but their incorporation into clinical practice is likely to yield significant benefits.

Time variation of some selected topics in bioethical publications

Objective: To analyse the time variation of topics in bioethical publications as a proxy of the relative importance. Methods: We searched the Medline database for bioethics publications using the words “ethics or bioethics”, and for 360 specific topics publications, associating Medical Subject Heading topic descriptors to those words. We calculated the ratio of bioethics publications to the total publications of Medline, and the ratio of each topic publications to the total bioethics publications, for five-year intervals, from 1970 to 2004. We calculated the time variation of ratios, dividing the difference between the highest and lowest ratio of each topic by its highest ratio. Four topics were described, selected to illustrate different patterns of variation: “Induced Abortion”, “Conflict of Interest”, “Acquired Immunodeficiency Syndrome”, “Medical Education.” Results: The ratio of bioethics publications to total Medline publications increased from 0.003 to 0.012. The variation of the topic’s ratios was higher than 0.7 for 68% of the topics. The Induced Abortion ratios decreased from 0.12 to 0.02. Conflict of Interest ratios increased from zero to 0.07. The Acquired Immunodeficiency Syndrome ratios were nearly zero in the first three intervals, had a peak of 0.06 during 1985–9, followed by a decrease to 0.01. Medical Education ratios varied few, from 0.04 to 0.03. Conclusions: There was an increase of bioethical publications in the Medline database. The topics in bioethics literature have an important time variation. Some factors were suggested to explain this variation: current legal cases, resolution of the issue, saturation of a discussion and epidemiologic importance.

Intra- and interobserver reproducibility of Bruch's membrane opening minimum rim width measurements with spectral domain optical coherence tomography

To investigate the reproducibility of Bruchs membrane opening minimum rim width (BMO‐MRW) and retinal nerve fibre layer thickness (RNFLT) measurements using spectral domain optical coherence tomography (SD‐OCT). Additionally, to investigate the reproducibility of BMO area measurements and fovea to BMO centre (FoBMO) angle.

Visibility of Optic Nerve Head Structures With Spectral-domain and Swept-source Optical Coherence Tomography

Purpose: To compare the visibility of deep optic nerve head (ONH) structures and the visible area of the anterior surface of the lamina cribrosa (ASLC) with spectral-domain optical coherence tomography (SD-OCT) and swept-source OCT (SS-OCT). Materials and Methods: In total, 33 glaucoma patients were imaged with SD-OCT (Spectralis, 24 radial B-scans centered on the ONH) and SS-OCT (Atlantis, 12 radial and a horizontal and vertical raster scan pattern containing 5 lines each, centered on the ONH). One of the SS-OCT horizontal and vertical scans that was best matching with the horizontal and vertical scan lines with those of SD-OCT was selected. All B-scans were then exported and deidentified. An independent observer determined whether the posterior choroid, border tissue, anterior scleral canal opening, and LC insertion into the sclera were detectable in the matched scan lines. Bruch membrane opening (BMO) and ASLC were segmented manually in radial scans. The segmented points were combined into a single plane and a linear interpolation was used to define BMO and ASLC areas. Results: The posterior choroid, border tissue, and anterior scleral canal opening were detectable in most patients (94% to 100%, 88% to 100%, and 76% to 100%, respectively) and were not different between SD-OCT and SS-OCT. The LC insertion detection rate was nonstatistically higher for SS-OCT compared with SD-OCT (58% to 85% vs. 42% to 73%; P>0.10). The mean (SD) ASLC visible area (percentage of the respective BMO area) was 124 (30%) with SD-OCT and 135 (32%) with SS-OCT (P<0.01). Conclusion: SD-OCT and SS-OCT had comparable detection rates of deep ONH structures; however, a larger area of ASLC was visible with SS-OCT.

Rates of glaucomatous visual field change after trabeculectomy

Background Trabeculectomy is frequently performed in patients with glaucoma who are deteriorating, although its effects on rates of visual field (VF) progression are not fully understood. We studied the rate of VF progression post trabeculectomy comparing with medically treated patients matched for VF loss. Methods Medical records of patients who underwent trabeculectomy alone or combined with cataract extraction were reviewed. Patients with 5 or more 24–2 VF examinations post trabeculectomy were selected. The rate of mean deviation (MD) change after surgery was calculated for each patient. These patients were pairwise matched based on baseline MD with patients with glaucoma who were treated medically and had at least 5 VF tests. Results 180 surgical patients were identified and matched with 180 medically treated patients (baseline MD of −8.72 (5.24) dB and −8.71 (5.22) dB, respectively). Surgically and medically treated patients were followed for 7.4 (2.9) and 6.8 (3.1) years respectively. The MD slopes were −0.22 (0.55) dB/year and −0.08 (1.10) dB/year in the surgically and medically treated patients, respectively, and not statistically different (p=0.13, 95% CI −0.31 to 0.04). More patients in the surgical group had fast progression (rates worse than −1 dB/year) than in the medical group (17 and 7 patients, respectively, p=0.05). Conclusions Our findings suggest that most patients who undergo trabeculectomy demonstrate relatively slow rates of VF progression postoperatively, similar to patients treated medically, although some patients can continue to progress despite adequate surgical control of intraocular pressure.

Assessing retinal ganglion cell damage

Retinal ganglion cell (RGC) loss is the hallmark of optic neuropathies, including glaucoma, where damage to RGC axons occurs at the level of the optic nerve head. In experimental glaucoma, damage is assessed at the axon level (in the retinal nerve fibre layer and optic nerve head) or at the soma level (in the retina). In clinical glaucoma where measurements are generally limited to non-invasive techniques, structural measurements of the retinal nerve fibre layer and optic nerve head, or functional measurements with perimetry provide surrogate estimates of RGC integrity. These surrogate measurements, while clinically useful, are several levels removed from estimating actual RGC loss. Advances in imaging, labelling techniques, and transgenic medicine are making enormous strides in experimental glaucoma, providing knowledge on the pathophysiology of glaucoma, its progression and testing new therapeutic avenues. Advances are also being made in functional imaging of RGCs. Future efforts will now be directed towards translating these advances to clinical care.

Protruded retinal layers within the optic nerve head neuroretinal rim

To determine the frequency with which retinal tissues other than the nerve fibre layer, hereafter referred to as protruded retinal layers (PRL), are a component of optical coherence tomography (OCT) neuroretinal rim measurements.

Long-term Outcome of Surgical Treatment for Late Intraocular Lens Dislocation Associated With High Intraocular Pressure: A Case Series

Purpose: To demonstrate the long-term safety and efficacy of transscleral intraocular lens (IOL) fixation combined with an Ahmed glaucoma drainage device implantation for patients with late IOL dislocation and high intraocular pressure (IOP). Methods: This is a retrospective report of a series of patients who underwent this combined surgery. The main outcome variables studied were change in visual acuity (VA), IOP, and number of medications compared with preoperative levels. Surgical failure was defined as a decrease in VA of at least 3 Snellen lines, IOP above 20 mm Hg or IOP reduction <25% from preoperative levels at ≥2 consecutive visits, at least 2 months apart. Results: Eleven patients with median age of 83 years (range, 77 to 92 y) were included in the study. All patients had a previous diagnosis of pseudoexfoliation. After a median follow-up time of 1.75 years (range, 0.83 to 2.5 y), the median IOP decreased from 33 mm Hg (range, 24 to 47 mm Hg) to 13 mm Hg (range, 5 to 16 mm Hg; P<0.01). The number of glaucoma medications also decreased from 3 (range, 1 to 4) to 2 (range, 0 to 4; P=0.03). The median log MAR VA improved from 0.77 (range, 0.3 to 2) preoperatively to 0.44 (range, 0 to 3) postoperatively (P=0.27). Four patients had postoperatory surgical complications: choroidal effusion (2), vitreous hemorrhage and hyphema (1), vertical diplopia (1). The survival probability over 2.5 years was 90.9% (confidence interval, 75.4%-100%). Conclusion: Transscleral IOL fixation associated with Ahmed glaucoma drainage device implantation is a safe and effective surgical option for patients with late IOL dislocation and elevated IOP.