JoAnn A. Giaconi

Structure-function relationships between spectral-domain OCT and standard achromatic perimetry.

PURPOSE To explore structure-function relationships in early glaucoma with spectral-domain optical coherence tomography (SD-OCT) and standard achromatic perimetry. METHODS One hundred thirty-six eyes of 97 patients with suspected or early glaucoma were enrolled from the clinical database at UCLAs Glaucoma Division. All patients had good-quality peripapillary retinal nerve fiber layer (RNFL)/optic disc measurements and a reliable 24-2 SITA-Standard Humphrey visual field (VF) within a 6-month period. Correlations of global and sectoral RNFL thickness and rim area (RA) measurements, with corresponding global and regional VF sensitivities (both in logarithmic [dB] and 1/Lambert scales [1/L]), were investigated with components of variance models. RESULTS The average RNFL thickness, RA, and mean deviation (MD) were 85.6 ± 5.7 μ, 1.0 ± 0.3 mm(2), and -1.3 ± 1.9 dB, respectively. Global RA demonstrated a stronger correlation with MD compared to average RNFL thickness (P = 0.002). The highest correlations were observed between superonasal VF cluster (in dB scale) and inferotemporal RA (R(2) = 0.26, 95% CI: 0.15-0.40) or inferotemporal RNFL thickness (R(2) = 0.24, 95% CI: 0.13-0.37). In glaucoma suspects, the highest correlations were seen between superonasal VF cluster and inferotemporal RA (R(2) = 0.16) in dB scale or RNFL thickness (R(2) = 0.10) in 1/L scale. Correlations were slightly greater with dB scale than 1/L scale and tended to be linear with both scales. CONCLUSIONS Structure-function relationships can be detected in early glaucoma with SD-OCT. Correlations of RA with VF thresholds tended to be higher compared to those of RNFL. Structure-function relationships were well described with a linear model.

Measurement of optic disc size and rim area with spectral-domain OCT and scanning laser ophthalmoscopy.

PURPOSE To compare optic disc and neuroretinal rim area measurements from spectral-domain optical coherence tomography (SD-OCT) to those from confocal scanning laser ophthalmoscopy. METHODS Seventy-one eyes from 43 normal subjects or suspected/definite glaucoma patients were prospectively enrolled. All subjects had biometry with the IOLMaster and disc/retinal nerve fiber layer imaging with Cirrus SD-OCT (Optic Disc Cube 200×200) and Heidelberg Retina Tomograph (HRT). Uncorrected disc and rim areas and measurements corrected for eye magnification with Bennetts formula (AL-corrected measurements), along with 30° sectoral rim areas, vertical cup-to-disc ratio (VCDR), and cup volume, were compared between the two devices. RESULTS The median (range) axial length (AL) was 24.2 mm (22.4-27.7 mm). Mean keratometry-corrected HRT disc area measurements were larger than AL-corrected HRT and SD-OCT measurements (P < 0.001 for both) and the difference was a function of keratometry measurements (K-readings). The AL-corrected HRT disc area and uncorrected/corrected Cirrus disc areas were not significantly different (P > 0.481). HRT rim area was larger than Cirrus measurements (P < 0.001) and the difference decreased with decreasing rim area. HRT VCDR and cup volume were significantly smaller than Cirrus measurements (P < 0.001). The correlations for sectoral rim areas between the two devices were moderate at best (intraclass correlation coefficients = 0.12-0.65). CONCLUSIONS HRT overestimated optic disc area as compared to SD-OCT. A portion of the difference in HRT and SD-OCT disc measurements is due to HRTs magnification correction algorithm. Rim area measurements from HRT were larger than from SD-OCT, likely a result of different definitions for the reference plane and differences in disc area measurements. Disc parameters from the two devices are not interchangeable.

Measurement of the Optic Disc Vertical Tilt Angle With Spectral-Domain Optical Coherence Tomography and Influencing Factors

PURPOSE To report a novel method for measuring the vertical tilt angle of the optic nerve (ON) head and to investigate the associated factors. DESIGN Cross-sectional diagnostic study. METHODS One hundred and twelve normal, glaucomatous, and glaucoma suspect eyes (99 patients) were enrolled in this study. Subjects underwent a full eye examination, biometry, and spectral-domain optical coherence tomography (SDOCT). The vertical tilt angle was measured on high-resolution cross-sectional SDOCT images passing through the ON head and foveal centers using the inner edges of the Bruch membrane opening as the reference plane. The correlation between the vertical tilt angle with the ovality index and the potential associated factors was estimated with univariate and multivariate linear regression analyses. RESULTS The median (interquartile range, [IQR]) axial length and visual field mean deviation were 24.5 (23.8-25.3) mm and -0.9 (-2.76 to 0.26) dB. The median (IQR) tilt angle was 3.5 (1.2-11.2) degrees. There was a moderate correlation between the ovality index and tilt angle (Spearman ρ = 0.351; P < .001). In univariate analyses, axial length, spherical equivalent, and mean deviation were correlated with the tilt angle (P = .002, P = .011, and P = .013, respectively). Axial length, mean deviation, and their interaction showed a statistically significant correlation with the tilt angle in multivariate analyses (P = .044 for axial length, P = .039 for mean deviation, and P = .028 for their interaction). CONCLUSIONS We describe a new method for measuring the ON head vertical tilt angle with high-resolution SDOCT imaging. The ovality index demonstrated only a moderate correlation with the tilt angle measurements and hence is not a good proxy measure for the vertical ON head tilt angle. Axial length and visual field mean deviation are the main factors associated with the ON head vertical tilt angle. The underlying basis for the relationship of vertical tilt angle and glaucoma severity should be further explored.

CT scan evidence of dysthyroid optic neuropathy.

Purpose To determine the utility of CT imaging in identifying patients with dysthyroid optic neuropathy. Methods Orbital CT scans of 12 randomly selected patients with dysthyroid optic neuropathy and 15 control subjects with Graves orbitopathy were retrospectively reviewed by two investigators blinded to the clinical data. The clinical diagnosis of optic neuropathy was made by one author before obtaining CT images and was based on clinical features. Results Optic nerve crowding (P <0.001) and intracranial fat prolapse (P <0.05) were the imaging features independently related to optic neuropathy. A muscle index greater than 50% had excellent sensitivity (100%) but did not have high specificity (47%) for dysthyroid optic neuropathy. Superior ophthalmic vein dilation and proptosis did not show significant relations with optic neuropathy. Conclusions This study suggests that patients with Graves orbitopathy who have severe optic nerve crowding, intracranial fat prolapse, and/or muscle index greater than 50% present on orbital CT scans are more likely to have coexisting optic neuropathy.

The Association of Consumption of Fruits/Vegetables With Decreased Risk of Glaucoma Among Older African-American Women in the Study of Osteoporotic Fractures

PURPOSE To explore the association between consumption of fruits and vegetables and the presence of glaucoma in older African-American women. DESIGN Cross-sectional study. METHODS Disc photographs and suprathreshold visual fields were obtained from the 662 African-American participants in the Study of Osteoporotic Fractures. Masked, trained readers graded all discs, and 2 glaucoma specialists reviewed photographs and visual fields. The Block Food Frequency Questionnaire assessed food consumption. Relationships between selected fruit/vegetable/nutrient consumption and glaucoma were evaluated using logistic regression models after adjusting for potential confounders. RESULTS After excluding women missing Food Frequency Questionnaire and disc data, 584 African-American women (88.2% of total African-American cohort) were included. Glaucoma was diagnosed in at least 1 eye in 77 subjects (13%). Women who ate 3 or more servings/day of fruits/fruit juices were 79% (odds ratio [OR] = 0.21; 95% confidence interval [CI]: 0.08-0.60) less likely to have glaucoma than women who ate less than 1 serving/day. Women who consumed more than 2 servings/week of fresh oranges (OR = 0.18; 95% CI: 0.06-0.51) and peaches (OR = 0.30; 95% CI: 0.13-0.67) had a decreased odds of glaucoma compared to those consuming less than 1 serving/week. For vegetables, >1 serving/week compared to ≤1 serving/month of collard greens/kale decreased the odds of glaucoma by 57% (OR = 0.43; 95% CI: 0.21-0.85). There was a protective trend against glaucoma in those consuming more fruit/fruit juices (P = .023), fresh oranges (P = .002), fresh peaches (P = .002), and collard greens/kale (P = .014). Higher consumption of carrots (P = .061) and spinach (P = .094) also showed some associations. Individual nutrient intake from food sources found protective trends with higher intakes of vitamin A (P = .011), vitamin C (P = .018), and α-carotene (P = .021), and close to statistically significant trends with β-carotene (P = .052), folate (P = .056), and lutein/zeaxanthin (P = .077). CONCLUSION Higher intake of certain fruits and vegetables high in vitamins A and C and carotenoids may be associated with a decreased likelihood of glaucoma in older African-American women. Randomized controlled trials are needed to determine whether the intake of specific nutrients changes the risk of glaucoma.

Graft Failure After Penetrating Keratoplasty in Eyes With Ahmed Valves

PURPOSE To determine incidence and risk factors for graft failure following penetrating keratoplasty (PK) in eyes with Ahmed valves (AV). DESIGN Retrospective, observational cohort study. METHODS Patients who underwent PK after AV implantation (both performed at our institution through 2004) were studied. Intervals to graft failure (defined as either dysfunction [stromal thickening with retention of clarity] or decompensation [central microcystic edema or loss of clarity]) were analyzed using Kaplan-Meier technique. Risk factors for graft failure were analyzed using Cox proportional hazard models. RESULTS Included were 77 eyes (77 patients; first procedure 1993). Following PK, 40 eyes (52%) required increased numbers of glaucoma medications; 10 eyes (13%) required additional glaucoma drainage device(s). Graft failure at 1, 2, and 3 years was 42.4% (95% confidence interval: 32.0%-54.6%), 57.1% (45.6%-69.1%), and 59.1% (47.5%-71.2%), respectively. Prior PK (HR 2.38, P = .006) and stromal vessels (HR 2.90, P = .0005) were associated with increased risk of graft failure. Use of glaucoma medications (HR 0.27, P = .009) and evidence of lower intraocular pressures (IOP) during follow-up (excluding hypotony; HR 0.92, P = .010) were associated with reduced risk of graft failure. Endothelial rejection episodes were observed in 13 eyes (17%); however, rejection was not a risk factor for graft failure (P = .98). CONCLUSIONS Long-term survival of corneal grafts is poor in eyes with AV. The majority of graft failures are associated with progressive loss of endothelial function, without observed immunologic rejection. Despite the presence of an AV, escalation in glaucoma therapy often follows PK; graft failure may be related to poor IOP control.

Retinal nerve fiber thickness is reduced in sleep apnea syndrome

OBJECTIVE To investigate the prevalence of glaucoma, visual field abnormalities, as well as changes in retinal nerve fiber layer in patients with obstructive sleep apnea syndrome (OSAS). METHODS In this cross-sectional study, 51 patients with OSAS were included. Based on apnea hypopnea index (AHI), there were 26, 6 and 19 cases of severe (AHI⩾30), moderate (15⩽AHI<30), and mild (5⩽AHI<15) OSAS, respectively. The control group was matched for age, sex and body mass index. Prevalence of glaucoma and ocular hypertension as well as the following values were assessed and compared between two groups: best-corrected visual acuity, intraocular pressure, central corneal thickness (CCT), cup:disk ratio, mean deviation (MD), pattern standard deviation, and retinal nerve fiber layer (RNFL) parameters using glaucoma diagnosis measurement (GDx). RESULTS Seven eyes (6.7%) had intraocular pressure (IOP)>21mmHg; of these, four eyes (3.9%) had glaucoma. No significant difference was detected in CCT between the two groups. IOP was significantly higher in the OSAS group before (p<0.001) and after (p<0.001) correcting for CCT. There was a significant difference between groups in MD and most GDx parameters including DISK (temporal-superior-nasal-inferior-temporal) average (p=0.002), superior average (p=0.05) and nerve fiber indicator (NFI) (p=0.03), where those in the patient group showed lower values. There was a significant positive correlation between AHI and both IOP and NFI. CONCLUSIONS OSAS patients had a higher prevalence of glaucoma and ocular hypertension. OSAS patients also had higher IOP, worse visual field indices, and lower RNFL parameters compared with the control group.

Long-Term Bleb-Related Infections After Trabeculectomy: Incidence, Risk Factors, and Influence of Bleb Revision

PURPOSE To report the incidence of late-onset bleb-related infections and to identify risk factors for bleb-related infections after trabeculectomy for the treatment of glaucoma. DESIGN Retrospective case series. METHODS Bleb-related infections were defined as blebitis, endophthalmitis, or blebitis with endophthalmitis. A total of 1959 eyes of 1423 patients who underwent trabeculectomy and who were followed for ≥1 year were included. RESULTS Twenty-four eyes were diagnosed with bleb-related infections; 15 eyes were found to have blebitis and 9 eyes presented with endophthalmitis during the follow-up period of 5.4 ± 3.5 years (mean ± standard deviation). Among 15 eyes with blebitis, 2 eyes developed endophthalmitis under treatment. The Kaplan-Meier estimated incidence of bleb-related infections was 2.0% ± 0.5% (mean ± standard error) at 10 years. A Cox multivariate analysis showed the significant risk factors for a bleb-related infection to be diagnoses of pigmentary glaucoma or juvenile glaucoma, history of bleb leak, intraocular pressure sustained below the target pressure, chronic blepharitis, and the presence of punctal plugs. Surgical bleb revision demonstrated a protective effect against bleb-related infections (P < .01) when risk factors were present. CONCLUSIONS This large case series with long-term follow-up demonstrates the incidence of bleb-related infections to be less than 2%, and describes the risk factors associated with bleb-related infections. A protective effect of surgical bleb revision was demonstrated. Clinicians should be constantly vigilant for, and patients made aware of, the possibility of bleb-related infections long after trabeculectomy, especially in the presence of identified risk factors.

A comparison of semiautomated versus manual Goldmann kinetic perimetry in patients with visually significant glaucoma.

PurposeTo determine if semiautomated kinetic perimetry (SKP) is reproducible and comparable to Goldmann manual kinetic perimetry (GVF). MethodsGlaucoma patients were recruited to perform visual field testing using GVF and SKP. Specific isopters were tested, quantified, and compared. Visual field patterns were analyzed for shape and defect. ResultsTen patients (16 eyes) underwent visual field studies using SKP and GVF, and 8 patients completed a second SKP on a different day. Individual isopter areas were similar between GVF and SKP, although 60% of isopters were larger on SKP by an average of 15%. This was statistically significant for the smaller isopters, I4e (P=0.02) and I2e (P=0.05). Retesting with SKP on a separate day, showed similar isopter areas (P values=0.3 to 1.0), however, the exact location of isopters in degrees from central fixation tended to vary with the smaller test object sizes. Isopter position in degrees from the central axis agreed in at least 3 quadrants in approximately 65% of fields compared. SKP visual field defects and patterns were similar between test strategies. ConclusionsSKP and GVF testing produce similar visual field results in glaucoma patients, and SKP testing seems to be reliable and reproducible in this population. However, overlapping isopters, typically associated with nonorganic vision loss, and jagged isopters were sometimes observed in SKP visual fields. Further study of SKP is needed to explore these findings.

Valved Glaucoma Drainage Devices in Pediatric Glaucoma Retrospective Long-term Outcomes

IMPORTANCE Relatively little data exist about the long-term outcomes of an initial glaucoma drainage device (GDD) and subsequent GDDs implanted in pediatric patients with glaucoma. OBJECTIVE To determine the long-term outcomes of the first and second GDDs and risk factors in pediatric glaucoma. DESIGN, SETTING, AND PARTICIPANTS Retrospective review of 119 eyes of 89 patients younger than 18 years with glaucoma who underwent valved GDD implantation from March 1999 to April 2012 at the Stein Eye Institute, University of California, Los Angeles. EXPOSURE Implantation of GDD, using silicone and polypropylene Ahmed glaucoma valve. MAIN OUTCOMES AND MEASURES Kaplan-Meier survival analysis and risk factors associated with GDD failure. Success was defined as a final intraocular pressure of 5 to 21 mm Hg as well as a 20% reduction from baseline intraocular pressure with or without medications. RESULTS The mean (SD) age at implantation of the first GDD was 6.8 (5.7) years. The mean (SD) follow-up time was 6.1 (3.3) years from surgery. The mean intraocular pressure was reduced by 13.0 mm Hg (95% CI, 8.8 to 17.3 mm Hg) at 5 years postoperatively. The mean number of glaucoma medications preoperatively vs postoperatively was not different starting at 5 years (reduction of 0.5; 95% CI, -0.1 to 1.0). The success rate at 5 years was 55.0% (95% CI, 46.0% to 65.9%). Risk factor analysis suggests that older age (risk ratio = 0.95; 95% CI, 0.90 to 0.99; P = .02), uveitic glaucoma (risk ratio = 0.34; 95% CI, 0.14 to 0.86; P = .02), and polypropylene GDDs (risk ratio = 0.39; 95% CI, 0.23 to 0.67; P = .001) were associated with higher success rates. Thirty-six eyes received a second GDD, with a mean (SD) of 2.2 (1.6) years between the 2 operations. The success rate 5 years after the second surgery was 52.8% (95% CI, 37.0% to 75.3%). Risk factors associated with failure of the first GDD were not found to affect the likelihood of failure for the second. CONCLUSIONS AND RELEVANCE Glaucoma drainage devices, such as the Ahmed glaucoma valve, have moderate long-term success rates in pediatric patients with glaucoma. In pediatric patients, the first GDD is successful in 46% to 70% of patients at 5 years with medications, and the second GDD is successful in 37% to 75% of patients at 5 years after the subsequent surgery.