[Show abstract][Hide abstract] ABSTRACT: Purpose:
To evaluate the ability of the short-duration transient visual evoked potential (SD-tVEP) to discriminate between healthy eyes and eyes with early to advanced glaucomatous visual field loss.
We tested 30 eyes of 30 healthy controls and 45 eyes of 35 glaucoma patients. Normal eyes had 20/30 or better visual acuity and normal 24-2 Swedish interactive thresholding algorithm (SITA) Standard visual fields. Glaucoma was staged as mild (mean deviation, MD > -6.0 dB), moderate (MD between -6.0 and -12.0 dB), and severe (MD < -12.0 dB). There were 15 eyes in each group. SD-tVEPs were recorded using the Diopsys NOVA-LX System. Each eye was stimulated with a low (Lc) and a high (Hc) Michelson contrast checkerboard pattern. Each test resulted in an Lc and an Hc SD-tVEP response. Each response was evaluated for overall waveform quality, P100 latency, and P100 amplitude referenced to the N75. The sensitivity, specificity, negative predictor value (NPV), and positive predictor value (PPV) were calculated.
Lc latency showed the highest accuracy for discrimination using receiver operating characteristic curves for high and low contrast parameters. The analysis for all subjects resulted in a 91.1% sensitivity, 93.3% specificity, 95.3% PPV, and an 87.5% NPV. Evaluating the mean Lc latency of the mild, moderate, and severe glaucoma patients against controls showed discrimination consistent with the glaucoma severity.
Short-duration transient VEP objectively identified decreased visual function and discriminated between healthy and glaucomatous eyes, and also showed good differentiation between healthy eyes and those with early visual field loss. VEP may be useful for early diagnosis of glaucoma.
No preview · Article · Mar 2013 · Investigative ophthalmology & visual science
[Show abstract][Hide abstract] ABSTRACT: Purpose:
To investigate the relationship between optic disc progression and rates of visual field (VF) change in patients with treated glaucoma.
Glaucoma patients with repeatable VF loss, ≥8 SITA-Standard 24-2 VF tests and good quality optic disc stereophotographs evaluated over a 10-year period were included. Optic disc photographs were reviewed for signs of glaucoma progression (neuroretinal rim change, widening of retinal nerve fibre layer defect, disc haemorrhage and enlargement of beta-zone parapapillary atrophy) by two glaucoma specialists masked to their temporal sequence. Disagreements were adjudicated by a third grader. VF progression was evaluated using automated pointwise linear regression (PLR) and defined as at least two adjacent test points progressing >1.0 dB/year at p < 0.01. VF progression outcomes were compared with photograph review results.
Three-hundred and eighty nine eyes (389 patients; mean age 64.9 ± 13.0 years; mean baseline MD, -7.1 ± 5.1 dB) were included. Most patients had primary open angle glaucoma (54%). Eighty-two eyes (21%) had confirmed optic disc progression and 115 eyes (29%) met the VF PLR criteria. Eyes with documented optic disc progression had more rapid rates of VF change (-0.66 ± 0.7 versus -0.36 ± 0.7 dB/year, p < 0.01) and met the VF PLR endpoint more often (univariate OR = 1.85, p = 0.02; multivariate OR = 1.78, p = 0.03) than eyes without optic disc progression. There was moderate spatial consistency between the location of the optic disc progression and the hemifield with more rapid progression (81%, kappa = 0.40).
Treated glaucomatous eyes with documented optic disc progression are at increased risk of diminished visual function over time and may require more aggressive therapy to prevent future vision loss. Among the indicators of structural progression, disc haemorrhage was the single most significant predictor for VF deterioration.
Full-text · Article · Jan 2013 · Acta ophthalmologica
[Show abstract][Hide abstract] ABSTRACT: Background
To investigate anatomical configuration of ciliary body and iris using ultrasound biomicroscopy as a predictor of malignant glaucoma development. DesignRetrospective study in a tertiary care hospital. ParticipantsCohort of 31 consecutive patients diagnosed with post-surgical malignant glaucoma. Methods
Anterior chamber angle, iris and ciliary body configuration of involved eyes that had ultrasound biomicroscopy evaluation prior to the malignant glaucoma onset were evaluated. In cases with no presurgical ultrasound biomicroscopy exam of the involved eye, images from the fellow eye (imaged within 6 months) were analysed. Main Outcome MeasuresQualitative parameters. ResultsThirty-one eyes (31 patients) had confirmed malignant glaucoma between 1996 and 2008. Most patients were women (65%) and had an anatomical narrow angle or angle-closure glaucoma (77%). Mean intraocular pressure at diagnosis was 30.413.5 mmHg. The most common operation was trabeculectomy with mitomycin C (55%, 17/31 eyes), combined (3/17) or not (14/17) with cataract extraction and intraocular lens implantation. Among these 31 cases, we were able to evaluate the ultrasound biomicroscopy images of 13 patients (13 eyes) including involved eyes imaged prior to the malignant glaucoma onset or eligible fellow eyes. A narrow angle with or without iridotrabecular contact was found in all eyes. A large and/or anteriorly positioned ciliary body associated with an iris root angulating forward and centrally, revealing a plateau iris configuration, was noticed in 85% (11/13) of these eyes. Conclusion
Identification of plateau iris configuration by ultrasound biomicroscopy should be considered as a possible predictor of post-operative malignant glaucoma development.
Full-text · Article · Dec 2012 · Clinical and Experimental Ophthalmology
[Show abstract][Hide abstract] ABSTRACT: Introduction:
Anti-VEGF therapy has been widely used in the treatment of ocular neovascular diseases. Because of their anti-angiogenic and anti-fibrotic properties, anti-VEGF antibodies such as bevacizumab and ranibizumab have emerged as an adjunctive treatment modality in glaucoma to improve success of conventional treatments.
Ranibizumab is an anti-VEGF-A antigen binding fragment currently indicated in neovascular age-related macular degeneration as well as macular edema following retinal vein occlusion. Several off-label uses include the treatment of neovascular glaucoma to regress/suppress iris and iridocorneal angle neovascularization and the modulation of wound healing after glaucoma filtration surgery. Bevacizumab is a full-length anti-VEGF antibody, which is also being used in aforementioned eye conditions off-label. An overview of these anti-VEGF antibodies and the results of preclinical and clinical studies regarding their use in the treatment of glaucoma are presented.
Early studies on the utility of both bevacizumab and ranibizumab in neovascular glaucoma and filtration surgery reported promising results. However, a large-scale randomized clinical trial as well as comparative studies between the two anti-VEGF antibodies are currently lacking. A single dose of ranibizumab costs approximately 40 times as much as a single dose of bevacizumab. Clinicians should take this into account, in addition to their differences in the efficacy and safety, when treating patients.
No preview · Article · Sep 2012 · Expert opinion on biological therapy
[Show abstract][Hide abstract] ABSTRACT: Purpose: To investigate the spatial relationships of focal lamina cribrosa (LC) defects with glaucomatous structural (neuroretinal rim [NRR], retinal nerve fiber layer [RNFL], disc hemorrhage [DH]) and functional damage.
Methods: Serial horizontal and vertical enhanced depth imaging optical coherence tomography (EDI OCT) optic disc scans (interval between scans ~30 μm) were prospectively obtained for glaucomatous eyes. Focal LC defects were defined as localized LC disinsertions or full-thickness LC defects that violated the smooth curvilinear contour of the normal anterior laminar surface. The maximum width of each focal LC defect was required to be ≥100 µm. For eyes with focal LC defects, the anterior laminar surface and the LC defects were outlined using 3-dimensional reconstruction software (Fig. A-C). The locations of largest focal LC defect, greatest NRR loss, greatest FDOCT RNFL defect, deepest 24-2 visual field (VF) scotoma (based on pattern deviation map values), and ever-detected DH were determined using Garway-Heath mapping (Fig. D).
Results: 50 eyes (44 subjects) were included (mean age, 67±16 yr). In 49 eyes, the largest focal LC defects were detected in the temporal half of the LC (sectors 1 [10 eyes], 2 [31 eyes], 5 [1 eyes] and 6 [7 eyes]). The largest LC defects occurred in the same sector as the greatest NRR and RNFL defects in 47 eyes (all P<0.001, Cramer’s correlation coefficient V=0.955). The largest LC defects spatially corresponded to the densest scotoma in 44 eyes (P<0.001, V=0.807) (Fig. E and F). In 5/6 eyes with spatial discrepancy between focal LC defects and NRR, RNFL or VF defects, the largest focal LC defects occurred adjacent to the sectors of the greatest NRR, RNFL and VF defects. DH was detected in 9 eyes and occurred at the margin of the largest (or second largest) focal LC defect in 8 eyes (P<0.001, V=0.913).
Conclusions: Focal LC defects showed an excellent spatial correlation with glaucomatous structural changes (NRR loss, RNFL defect and DH) and functional damage. The precise relationship between focal LC damage and the development of DH warrants further investigation.
[Show abstract][Hide abstract] ABSTRACT: Background: To determine if optic disc phenotype is correlated with the rate of glaucomatous visual field progression.
Design: Retrospective cohort.
Participants or Samples: Treated glaucoma patients.
Methods: The optic disc stereophotographs of glaucoma patients were reviewed by two investigators masked to all clinical and perimetric data. Each disc was classified as focal ischaemic, myopic, senile sclerotic and generalized enlargement. Visual field progression (defined as at least two adjacent test points in the same hemifield progressing by more than 1.0 dB/year at P < 0.01) was evaluated using automated pointwise linear regression.
Main Outcome Measures: Association between optic disc phenotypes and other clinical variables and rates of visual field progression.
Results: 264 optic disc stereophotographs (127 generalized enlargement, 41 focal ischaemic, 54 myopic and 42 senile sclerotic) were evaluated. In the univariate analyses, it was found that patients with senile sclerotic discs were older (p = 0.002) and those with generalized enlargement had better baseline visual field mean deviation (p < 0.001) and higher intraocular pressure (p = 0.006) compared with the other groups. More disc haemorrhages were detected in the focal ischaemic and senile sclerotic groups (p = 0.010). After adjusting for other risk factors (intraocular pressure, age, central corneal thickness, disc haemorrhage), there were no differences among groups regarding the risk (p = 0.58) and velocity (p = 0.21) of visual field progression.
Conclusions: Visual field progression was similar among the four optic disc phenotypes in treated glaucoma after adjusting for other known risk factors. The division of disc appearance into clinical phenotypes does not appear to provide independent information regarding the risk of progression in clinical practice.
No preview · Article · Mar 2012 · Clinical and Experimental Ophthalmology
[Show abstract][Hide abstract] ABSTRACT: To assess the usefulness of enhanced depth imaging (EDI) optical coherence tomography (OCT) for evaluating deep structures of the optic nerve complex (ONC; optic nerve head and peripapillary structures) in glaucoma.
Prospective, observational study.
Seventy-three established glaucoma patients (139 eyes) with a range of glaucomatous damage.
Serial horizontal and vertical EDI OCT images of the ONC were obtained from both eyes of each participant. Deep ONC structures, including the lamina cribrosa (LC), short posterior ciliary artery (SPCA), central retinal artery (CRA), central retinal vein (CRV), peripapillary choroid and sclera, and subarachnoid space around the optic nerve, were investigated for their visibility and morphologic features.
Deep ONC structures identified in EDI OCT images.
Visual field mean deviation of 139 included eyes was -11.8 ± 8.6 dB (range, -28.70 to -2.01 dB). The anterior laminar surface was identified in all eyes in the central laminar area and in 91 (65%) eyes in the periphery beneath the neuroretinal and scleral rims or vascular structures. The LC pores with various shapes and sizes were visualized in 106 (76%) eyes, mainly in the central and temporal areas of the LC. Localized LC lesions seen on optic disc photographs were identified as focal LC defects (partial loss of LC tissue) in the EDI OCT images. The locations of the CRA and CRV were identified in all eyes. In the LC, the CRA maintained a straight shape with a consistent caliber, but the CRV (and tributaries) assumed a more irregular shape. The SPCAs, their branches through the emissary canals in the sclera, or both were visualized in 120 (86%) eyes. The subarachnoid space around the optic nerve was identified with varying degrees of clarity in 25 eyes (18%): 17 had high myopia and extensive parapapillary atrophy. Intrachoroidal cavitation or choroidal schisis, which had been unrecognized clinically, was identified in 2 eyes (1%) with high myopia.
Enhanced depth imaging OCT was able to visualize a wide variety of deep ONC structures in glaucoma patients and may be helpful in detecting, conceptualizing, and understanding basic and complicated in vivo anatomic and pathologic features of the ONC in glaucoma.
Proprietary or commercial disclosure may be found after the references.
[Show abstract][Hide abstract] ABSTRACT: To assess the general morphology and position of the lamina cribrosa (LC) in healthy subjects using enhanced depth imaging-optical coherence tomography (EDI-OCT).
Serial horizontal and vertical B-scans of the optic nerve head (interval between images, approximately 30 μm) were prospectively obtained using EDI-OCT for both eyes of each healthy subject. After delineation of the anterior laminar surface, mean and maximum LC depths were measured in 11 equally spaced horizontal B-scans, and the depth of the anterior LC insertion was measured at 32 points along its circumference (reference plane, Bruch's membrane edges) for one randomly selected eye of each subject. Three-dimensional (3D) images of the anterior laminar surface and the peripapillary sclera were reconstructed from serial horizontal EDI-OCT B-scans to assess the 3D morphology of the anterior laminar surface.
Among the 61 eyes (61 subjects) enrolled, 31 were excluded because of poor LC image quality, and 30 were included for analysis (mean age, 40 ± 18 [range, 21-78] years). Both mean and maximum LC depth profiles showed an elevation in the central area and a depression in the superior and inferior midperiphery of the LC. The anterior LC insertion was more posteriorly located in the superior and inferior than in the nasal and temporal regions. Three-dimensional LC images showed a bowtie-shaped horizontal central ridge of the LC.
The LC has a central ridge ranging from the temporal to the nasal insertion areas and inserts more posteriorly in the superior and inferior than in the nasal and temporal regions. Further investigation is needed to elucidate the significance of these findings in the pathophysiology of glaucoma.
No preview · Article · Jan 2012 · Investigative ophthalmology & visual science
[Show abstract][Hide abstract] ABSTRACT: To assess focal lamina cribrosa (LC) defects in glaucoma using enhanced depth imaging optical coherence tomography and to investigate their spatial relationships with neuroretinal rim and visual field loss.
Serial horizontal and vertical enhanced depth imaging optical coherence tomographic images of the optic nerve head were obtained from healthy subjects and those with glaucoma. Focal LC defects defined as anterior laminar surface irregularity (diameter, >100 μm;depth, >30 μm) that violates the normal smooth curvilinear contour were investigated regarding their configurations and locations. Spatial consistency was evaluated among focal LC defects, neuroretinal rim thinning/notching, and visual field defects.
Forty-six healthy subjects (92 eyes) and 31 subjects with glaucoma (45 eyes) were included. Ninety-eight focal LC defects representing various patterns and severity of laminar tissue loss were found in 34 eyes with glaucoma vs none in the healthy eyes. Seven of 11 eyes with glaucoma with no visible focal LC defect had a deeply excavated optic disc with poor LC visibility. Eleven focal LC defects presented clinically as an acquired pit of the optic nerve, and the others as neuroretinal rim thinning/notching. Focal LC defects preferably occurred in the inferior/inferotemporal far periphery of the LC including its insertion. Eyes with focal LC defects limited to the inferior half of the optic disc had greater sensitivity loss in the superior visual hemifield and vice versa.
Mechanisms of LC deformation in glaucoma include focal loss of laminar beams, which may cause an acquired pit of the optic nerve in extreme cases.Focal LC defects occur in tandem with neuroretinal rim and visual field loss.
No preview · Article · Jan 2012 · Archives of ophthalmology
[Show abstract][Hide abstract] ABSTRACT: PURPOSE:: To report on the usefulness of combined Baerveldt glaucoma implantation (BGI) and scleral buckling surgery for patients with glaucoma requiring a scleral buckle for retinal detachment repair. METHODS:: Retrospective, consecutive, noncomparative, and interventional case series of 30 eyes (30 patients) that underwent simultaneous scleral buckle and BGI surgery, using a staged (group 1, n=21 patients) or nonstaged (group 2, n=9 patients) approach to BGI implantation. Successful intraocular pressure (IOP) control was defined as 6 mm Hg≤IOP≤18 mm Hg. RESULTS:: Although not statistically significant, mean best corrected visual acuity (LogMAR) improved from 2.0 before surgery to 1.7 after surgery (P=0.13) with a mean follow-up of 27.7 months. Of the 21 patients in group 1, only 13 (62%) required second-stage tube insertion at a mean of 7.0±8.0 months (range, 1 to 24 mo) postoperatively. For these eyes combined with group 2 eyes, mean IOP was reduced from 31.1±10.8 to 12.7±6.0 mm Hg (P<0.0001), and the mean number of glaucoma medications was reduced from 2.9±1.4 to 1.2±1.3 (P<0.001). Life table rates of successful IOP control were 90% and 80% at 12 and 24 months, respectively. CONCLUSIONS:: Combined scleral buckle and BGI is an effective technique for managing coexisting glaucoma and retinal detachment and provides the clinician with a useful surgical option while minimizing surgical risk.
Full-text · Article · Dec 2011 · Journal of glaucoma
[Show abstract][Hide abstract] ABSTRACT: Purpose: To determine whether glaucoma subtype is an independent risk factor for visual field (VF) progression.
Methods: We reviewed the charts of glaucoma suspects and glaucoma patients seen in a referral practice between 1999 and 2009. Automated pointwise linear regression analysis determined the rates of VF change. A progression endpoint was determined when two or more adjacent test locations in the same hemifield showed a threshold sensitivity decline at a rate of ≥1.0 dB/year with p < 0.01.
Results: We included 841 eyes (841 patients; mean age, 64.1 ± 12.6 years; mean number of VF tests, 10.8 ± 2.8; mean follow-up, 6.4 ± 1.7 years). The glaucomatous group consisted of angle-closure glaucoma (76 eyes), juvenile primary open-angle glaucoma (37 eyes), normal-tension glaucoma (81 eyes), pigmentary glaucoma (34 eyes), primary open-angle glaucoma (275 eyes) and exfoliative glaucoma (XFG, 84 eyes). Normal-tension glaucoma eyes were more likely to present with beta-zone parapapillary atrophy and disc haemorrhage (p < 0.01). Exfoliative glaucoma eyes had the fastest rates of global VF change (−0.65 dB/year), as well as the highest mean, fluctuation, and peak intraocular pressure during follow-up (16.5, 3.0 and 22.0 mmHg, respectively) and reached a progression endpoint more frequently (40%). After adjusting for all covariates, including the glaucoma phenotype, there was no difference among groups regarding global rates of VF change and the risk of reaching a progression endpoint.
Conclusions: Despite different clinical features, epidemiology and genetics, glaucoma phenotype is not an independent risk factor for VF progression. Rather, variations in well-known, reported risk factors remain important disease parameters that affect progression.
No preview · Article · Oct 2011 · Acta ophthalmologica
[Show abstract][Hide abstract] ABSTRACT: This study examined effects of uncorrected refractive errors (RE) in a short-duration transient visual evoked potential (SD t-VEP) system and investigated their role for objective measurement of RE. Refractive errors were induced by means of trial lenses in 35 emmetropic subjects. A synchronized single-channel EEG was recorded for emmetropia, and each simulated refractive state to generate 21 VEP responses for each subject. P100 amplitude (N75 trough to P100 peak) and latency were identified by an automated post-signal processing algorithm. Induced hypermetropia and myopia correlated strongly with both P100 amplitude and latency. To minimize the effect of baseline shift and waveform fluctuations, a VEP scoring system, based on software-derived P100 latency, amplitude and waveform quality, was used to estimate the RE. Using the VEP scores, a single VEP response had a high sensitivity and specificity for discerning emmetropia, small RE (<2 diopter) within a 2 diopter range and large RE (2-14 diopter) within a 4 diopter range. The VEP scoring system has a potential for objective screening of RE and for a more accurate 3-step objective refraction.
[Show abstract][Hide abstract] ABSTRACT: To evaluate the relationship between β-zone parapapillary atrophy (βPPA) and corneal hysteresis (CH) in patients with glaucoma.
Prospective, cross-sectional study.
Glaucoma patients aged 18 to 90 years with disc photographs within 12 months of the study visit were consecutively enrolled. Exclusion criteria included ocular surgery other than clear corneal phacoemulsification, myopia >6 diopters, contact lens use, and corneal abnormality. CH was measured using the Ocular Response Analyzer (ORA). Disc photographs were evaluated in a masked fashion for βPPA.
We enrolled 99 patients (mean age 67.6 years; 45 men, 54 women). Univariate analysis showed no significant difference in CH between eyes with and without βPPA (8.72 ± 0.23 vs 8.15 ± 0.27 mm Hg, P = .11). There were no differences in corneal resistance factor (CRF) (P = .47), central corneal thickness (CCT) (P = .11), ORA wave score (P = .23), age (P = .23), sex (P = .40), IOP (P = .86), or visual field mean deviation (VFMD) (P = .45). Eyes with βPPA were more myopic (-1.49 ± 0.27 vs -0.22 ± 0.31 diopters, P = .003). Multivariate analysis showed no significant difference in CH between eyes with and without βPPA (P = .38). Eyes with asymmetric βPPA also showed no significant difference in CH (8.97 ± 0.22 vs 9.10 ± 0.22 mm Hg, P = .69).
We found no significant differences in CH between eyes with and without βPPA or between fellow eyes with asymmetric βPPA.
No preview · Article · Sep 2011 · American Journal of Ophthalmology
[Show abstract][Hide abstract] ABSTRACT: To determine if visual field (VF) progression occurs most rapidly in the region of largest β-zone parapapillary atrophy (PPA).
One hundred twenty-five patients from the New York Glaucoma Progression Study with both β-zone PPA and VF progression.
Treated open-angle glaucoma patients with 8 or more Swedish Interactive Threshold Algorithm Standard 24-2 VFs (Humphrey Field Analyzer II; Carl Zeiss Meditec, Inc., Dublin, CA) in either eye were identified. Eyes with optic disc photographs, β-zone PPA, less than 6 diopters myopia, and VF progression were studied. Visual field progression was defined using trend analysis as the presence of at least 2 adjacent progressing points in the same hemifield using standard pointwise linear regression (PLR) criteria.
The correlation between β-zone PPA and location of most rapid future VF progression.
One hundred twenty-five eyes (125 patients; mean age, 71.9 ± 12.3 years; 58% women; 75% European descent) with β-zone PPA and VF progression were enrolled. The mean follow-up was 6.8 ± 1.7 years and the mean number of VFs was 12.5 ± 3.6. Ninety-three patients (74%) had more β-zone PPA inferiorly and 32 patients (26%) had more β-zone PPA superiorly. The fastest VF progression occurred in the superior hemifield in 77 patients (62%) and in the inferior hemifield in 48 (38%) patients. Patients with superior VF progression had a superior localized mean rate of progression of -1.57 ± 1.7 dB/year, and patients with inferior VF progression had an inferior localized mean rate of -0.94 ± 1.4 dB/year (P = 0.012). The mean number of points reaching the predefined PLR end points was 5.6±7.5 for the superior VF hemifield and 3.0±4.9 for the inferior hemifield (P = 0.006). The hemifield with more points reaching PLR progression end points, with fastest average velocity of progression, or both was spatially consistent with the location of largest β-zone PPA in 89 (71%) patients (P = 0.0001, Fisher exact test; κ = 0.35; 95% confidence interval, 0.17-0.53).
In treated glaucoma patients with β-zone PPA and VF progression, the location of largest β-zone PPA typically correlates spatially with the region of the most rapid future VF progression.
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
[Show abstract][Hide abstract] ABSTRACT: We investigated the correlation between central corneal thickness (CCT) and corneal hysteresis (CH) and their relationship with the rate of visual field (VF) change.
Glaucoma patients who underwent complete ophthalmic examination and tonometry using both the Goldmann applanation tonometer and the Ocular Response Analyzer were prospectively enrolled. Only eyes with ≥5 SITA Standard 24-2 VF tests were included. Automated pointwise linear regression analysis was used to determine VF progression. One hundred fifty-three eyes (153 patients; mean age, 61.3 ± 14.0 y; mean number of VF, 8.5 ± 3.4; mean follow-up time, 5.3 ± 2.0 y) met the enrollment criteria.
The mean global rate of VF change was -0.34 ± 0.7 dB/y. Twenty-five eyes (16%) reached a progression endpoint. Progressing eyes had lower CCT (525.0 ± 34.2 vs 542.3 ± 3 8.5 μm, P=0.04) and lower CH (7.5 ± 1.4 vs 9.0 ± 1.8 mm Hg, P<0.01) compared with nonprogressing eyes. CH and CCT correlated significantly (r=0.33, P<0.01). By multivariate analysis, peak intraocular pressure [odds ratio (OR)=1.13 per mm Hg higher, P<0.01], age (OR=1.57 per decade older, P=0.03), and CH (OR=1.55 per mm Hg lower, P<0.01) remained statistically significant.
Corneal biomechanical and physical properties, such as CH and CCT, are highly correlated and associated with VF progression. As CH may describe corneal properties more completely than thickness alone, it may be a parameter that is better associated with progression.
No preview · Article · Jun 2011 · Journal of glaucoma
[Show abstract][Hide abstract] ABSTRACT: To assess risk factors for an initial parafoveal scotoma (IPFS) compared with an initial nasal step (INS) in glaucoma.
Retrospective, observational study.
Sixty-nine patients with glaucoma with an isolated IPFS and 53 patients with an isolated INS.
On the basis of 2 reliable, consistent 24-2 Swedish interactive threshold algorithm standard visual fields (VFs), 2 groups of patients with glaucoma were studied: those with an IPFS in 1 hemifield (≥3 adjacent points with P<5% within the central 10 degrees of fixation, ≥1 point with P<1% lying at the innermost paracentral points, and no VF abnormality outside the central 10 degrees) and those with an INS in 1 hemifield (≥3 adjacent points with P<5% in the nasal periphery outside 10 degrees of fixation, the nasal-most point with P<1%, and no VF abnormality within the central 10 degrees). Clinical characteristics and systemic factors were recorded from charts and compared between the 2 groups.
Maximum untreated intraocular pressure (IOP), disc hemorrhage (DH) detection during follow-up, systemic risk factors, and VF mean deviation (MD) and pattern standard deviation (PSD).
Maximum untreated IOP (21.6±4.5 vs. 28.3±9.6 mmHg; P<0.001) was significantly lower, and frequency of DH detection (44% vs. 17%; P=0.001) and systemic risk factors (hypotension, migraine, Raynaud's phenomenon, and sleep apnea; 16%, 23%, 24%, and 9% vs. 0%, 4%, 9%, and 0%; P=0.001, 0.002, 0.025, and 0.030, respectively) were significantly higher in patients with an IPFS than in patients with an INS. There were no significant differences in age, gender, family history of glaucoma, refractive error, central corneal thickness, and disc area between the 2 groups (all P>0.1). Mean deviation was similar between the 2 groups (P=0.346), but PSD was significantly greater in the IPFS group than in the INS group (P=0.043).
Eyes with an IPFS differ from those with an INS. These findings may help clinicians identify patients at higher risk of early central field loss.
[Show abstract][Hide abstract] ABSTRACT: PURPOSE: We sought to determine whether filtering surgery, even when only partially successful, delays or slows visual field (VF) progression. METHODS: The records of all patients seen in a glaucoma referral practice from 1999 to 2009 were reviewed. Group A comprised eyes with ≥5 VFs before surgery and group B comprised eyes with ≥5 VFs after surgery. Eyes in group B were further divided into those requiring postoperative topical ocular hypotensive therapy (group B-2) and those that did not (group B-1). Automated pointwise linear regression was used to determine global rates (dB/y) of change and progression endpoints. A progression endpoint was determined when 2 or more adjacent test locations in the same hemifield showed a threshold sensitivity decline at a rate of ≥1.0 dB/year with P<0.01. RESULTS: A total of 206 treated eyes (206 patients; mean age, 63.8±13.0 y; 11.3±3.1 VFs; 6.4±1.8 y follow-up) were included. Mean global VF progression rates in group A (-0.86±0.8 dB/y) were faster than those in group B (-0.49±0.9 dB/y, P<0.01). Group A also had a greater risk of reaching a progression endpoint compared with group B (odds ratio=2.41, P<0.01). Groups B-1 and B-2 had different follow-up intraocular pressure means (12.7±3.7 vs. 15.5±2.7 mm Hg, respectively; P<0.01) and peaks (19.4±5.2 vs. 21.2±4.2 mm Hg; P=0.08). The velocity of VF progression was similar for groups B-1 and B-2 (-0.40±0.6 vs. -0.58±1.1 dB/y; P=0.22) and there was no significant difference between the 2 groups regarding the risk of reaching a progression endpoint (odds ratio=0.83, P=0.62). CONCLUSIONS: Filtering surgery reduces the rate of disease progression and this effect persists even if adjunctive glaucoma medical therapy is required.
No preview · Article · May 2011 · Journal of glaucoma
[Show abstract][Hide abstract] ABSTRACT: To investigate the correlation between structural and functional damage in patients with asymmetric glaucoma using a newly developed short duration transient visual evoked potential (SD-tVEP) device.
Twenty-five patients with visual acuity ≥20/30 and asymmetric visual field (VF) loss [inter-eye difference in mean deviation index (MD) of at least 3 dB] were enrolled. Patients underwent optical coherence tomography (OCT) for macular thickness measurement, scanning laser polarimetry with variable corneal compensation for retinal nerve fiber layer measurement, and SD-tVEP (10% and 85% Michelson contrast, acquisition time of 20 s) in both eyes within 2 months. We correlated VF MD and structural test results with SD-tVEP P100 latency and Delta Amplitude (N75-P100).
Using 10% contrast, there was a significant difference in SD-tVEP latency and amplitude between eyes with better and worse VF MD (P<0.001). MD correlated significantly with both SD-tVEP parameters (r>0.33, P≤0.01). When using 85% contrast, SD-tVEP amplitude differed between eyes (P=0.01) and MD values correlated significantly with amplitude results (r=0.32, P=0.01), but not with latency (P=0.46). In eyes with more advanced VF loss, there was a positive and significant correlation between SD-tVEP amplitude (85% contrast) and macular thickness on OCT (r=0.47, P=0.01), but not with retinal nerve fiber layer measured with polarimetry (P=0.26).
In cases of asymmetric glaucoma, SD-tVEP results correlate significantly with the level of VF damage as measured by MD. In the eyes with more advanced VF loss, reduced SD-tVEP amplitude was associated with decreased macular thickness on OCT. These findings suggest that SD-tVEP may be a fast and objective method to assess or screen for functional damage in glaucomatous eyes.
Full-text · Article · May 2011 · Journal of glaucoma