Frequency Doubling Technology Perimetry Results Research Articles

Association between esodeviation and primary open-angle glaucoma: the 2010–2011 Korea National Health and Nutrition Examination Survey

Background/AimsTo evaluate the association between strabismus and primary open-angle glaucoma (POAG) in a representative Korean population.MethodsA total of 11 114 participants aged 20 years or older in the Korea National...

Comparison of different methods of inter-eye asymmetry of rim area and disc area analysis

To describe different methods of inter-eye asymmetry of rim area (RA) to disc area (DA) asymmetry ratio (RADAAR) analysis. This was an observational, descriptive, and cross-sectional study. Both the eyes of all participants underwent confocal scanning laser ophthalmoscopy (Heidelberg retina tomograph (HRT 3)), frequency-doubling technology perimetry (FDT), and complete ophthalmological examination. Based on ophthalmological clinical examination and FDT results of the worse eye, subjects were classified as either normal, possible glaucoma, and probable glaucoma or definitive glaucoma. RADAAR values were calculated based on stereometric HRT 3 values using different mathematical formulae. RADAAR-1 was calculated as a relative difference of rim and DAs between the eyes. RADAAR-2 was calculated by subtracting the value of rim to DA ratio of the smaller disc from the value of rim to DA ratio of the larger disc. RADAAR-3 was calculated by dividing the previous two values. Statistical analyses included ANOVA as well as Student t-tests. Data of 334 participants were analysed, 78 of which were classified as definitive glaucoma. RADAAR-1 values were significantly different between the four different groups of diagnosis (F=5.82; P<0.001). The 1st and 99th percentile limits of normality for RADAAR-1, RADAAR-2, and RADAAR-3 in normal group were, respectively, -10.64 and 8.4; -0.32 and 0.22; and 0.58 and 1.32. RADAAR-1 seems to best distinguish between the diagnostic groups. Knowledge of RADAAR distribution in various diagnostic groups may aid in clinical diagnosis of asymmetric glaucomatous damage.

Screening for glaucoma with Moorfields regression analysis and glaucoma probability score in confocal scanning laser ophthalmoscopy

Objective To compare the validity of Moorfields regression analysis (MRA) and glaucoma probability score (GPS) of the confocal scanning laser ophthalmoscopy (Heidelberg retina tomograph 3; HRT3) in detecting glaucomatous optic nerve damage in a screening population. Design Population-based, cross-sectional study. Participants Subjects at high risk for development of open-angle glaucoma (OAG). Methods All subjects underwent confocal scanning ophthalmoscopy (Heidelberg retina tomograph; HRTII) testing, visual fields testing with frequency-doubling technology perimetry (FDT), and a standard ophthalmologic examination. All HRTII images were reprocessed with HRT3. Based on an ophthalmologic examination and FDT results, eyes were classified into 4 categories: normal, possible glaucoma, probable glaucoma, and definitive glaucoma. Main outcome measures included sensitivity and specificity of HRTII/MRA, HRT3/MRA, HRT3/GPS, and combination HRT3/MRA/GPS. Results The left eyes of 221 of 291 subjects were included; 4 (1.8%) eyes were classified as definitively having glaucoma. Depending on the reference standard diagnosis as well as on the borderline test-positive definition of the HRTII-3, sensitivity and specificity varied between 36.4% and 100%. For HRTII/MRA, 88.2% to 96.5%, 54.5% to 100%, and 74.5% to 93.6%; for HRT3/MRA, 61.9% to 100% and 64.3% to 85.2%; for HRT3/GPS, 85.7% to 100%; and for combination HRT3/MRA/GPS, 73.4% to 78.2%. Conclusions In this pilot study, the MRA of the HRT3 appears to be more sensitive but less specific than the MRA in the HRTII version. The GPS, although somewhat less specific than MRA (and some discs are nonclassifiable by this technique), had greater sensitivity and as a screening method may have the additional advantage of being contour-line independent.

Combining rim area to disc area asymmetry ratio and Moorfields regression analysis of confocal scanning laser ophthalmoscopy for glaucoma screening

Objective To determine the utility of combining rim area to disc area asymmetry ratio (RADAAR) and Moorfields regression analysis (MRA) to detect primary open-angle glaucoma (POAG) using confocal scanning laser ophthalmoscopy (CSLO) (Heidelberg retina tomograph 3 (HRT3)) in high-risk populations. Design Cross-sectional study. Participants Subjects with high risk for developing POAG. Methods Subjects underwent HRT, frequency doubling technology perimetry (FDT), and complete ophthalmic examination. Based on an ophthalmologic examination and FDT results of the worse eye, subjects were classified into 4 categories: normal, possible glaucoma, probable glaucoma, and definite glaucoma. Main outcome measures included sensitivities (Se), specificities (Sp), positive and negative predictive values (PPV, NPV), and positive and negative likelihood ratios (PLR, NLR) of the MRA, RADAAR, and combined MRA- RADAAR tests. Results Of 375 subjects, 11 were classified as having definite glaucoma. Depending on the reference standard, range results for Se, Sp, PPV, NPV, PLR, and NLR were, respectively, 57.7% to 100%; 55.1% to 85.4%; 6.3% to 39%; 92.6% to 100%; 1.97 to 4.9; 0 to 0.49 for MRA; 11.5% to 27.3%; 98.1% to 98.8%; 30% to 60%; 87.4% to 97.8%; 9.29 to 14.1; and 0.74 to 0.89 for RADAAR; and 57.7% to 90.9%; 81.3% to 85.1%; 12.8% to 38.5%; 92.6% to 99.7%; 3.87 to 4.85; 0.11 to 0.50 for combination MRA-RADAAR. Discussion When using HRT in populations at high risk for glaucoma, RADAAR had a higher specificity than MRA in identifying glaucoma. When patients were classified as borderline on MRA, combining RADAAR values decreased the number of false-positives as well, and may be recommended when high specificity is required.

Retinal Nerve Fiber Layer Thickness and Spatial and Temporal Contrast Sensitivity in Multiple Sclerosis

To measure peripapillary retinal nerve fiber layer (RNFL) thickness and spatial and temporal contrast sensitivity in multiple sclerosis (MS) taking into account previous history of optic neuropathy (ON). Thirty patients (60 eyes) with relapsing-remitting MS were selected (MS group). The MS ON group was composed of 31 eyes with previous history of optic neuropathy and the MS non-ON group of 29 eyes was without previous history of optic neuropathy. Thickness of the RNFL was measured with optical coherence tomography (OCT) with the Stratus OCT. As for sensitivity to spatial contrast,we used Pelli-Robson and Sloan charts. Sensitivity to temporal contrast was explored using frequency doubling technology perimetry (FDTP). The average thickness of RNFL in the MS, MS ON, MS non-ON, and control groups were 88.2 +/= 18.9 microm, 80.81 +/- 18.4 microm, 96.7 +/- 15.8 microm, and 106 +/- 12.2 microm, respectively. The spatial contrast vision and FDTP results were less in the MS non-ON group than in the control group. The average thickness of RNFL correlated to the scores of spatial and temporal contrast vision. MS is accompanied by visual function alteration even in the absence of acute optic neuropathy. The important correlation between functional and anatomic aspect confirms the value of OCT to appreciate the subclinical involvement of the optic nerve. Associated with tests exploring visual function, the OCT could reveal itself pertinent in evaluation of the different therapeutics used in MS ON.

Effect of driver distraction and low alcohol concentrations on useful field of view and frequency‐doubling technology perimetry

To investigate the effects of a mental psychometric task that simulates the distraction effect of a hands-free mobile phone and of low alcohol concentrations (0.3-0.5 g/l) on two tests: the useful field of view (UFOV) and frequency-doubling technology (FDT) perimetry. Thirty-seven healthy young vehicle drivers aged 22 +/- 3 years were subjected to a computer version of the UFOV test and FDT perimetry, undertaken according to a counterbalanced within-subject design. The tests were performed in two sessions (an 'alcohol session' and a 'sober session'), while undertaking or not undertaking a psychometric test [the Paced Auditory Serial Addition Test (PASAT)] to simulate the effect of distraction. Each subject was instructed to concentrate on the PASAT while taking each test. UFOV scores were affected when the PASAT was performed simultaneously (P < 0.0001) in that longer times were required to identify a central target and the location of a peripheral target. FDT perimetry was affected by the addition of the PASAT, with a significant reduction in mean sensitivity and a localized sensitivity loss [pattern standard deviation (PSD) >6 dB]. Test times, false-positive and negative catch trial responses were all increased. However, the UFOV test and FDT perimetry results were not significantly affected by a low alcohol concentration. Distraction significantly affects performance in the UFOV test and frequency-doubling technology perimetry. Our findings suggest that using a hands-free mobile phone while driving may lead to a low-to-moderate crash risk in young adults with normal visual function.

Retinal Nerve Fiber Layer Damage as Assessed by Optical Coherence Tomography in Eyes with a Visual Field Defect Detected by Frequency Doubling Technology Perimetry but Not by Standard Automated Perimetry

To determine whether the visual field (VF) loss detected by frequency doubling technology perimetry (FDT) but not by standard automated perimetry (SAP) is associated with retinal nerve fiber layer (RNFL) damage measured using optical coherence tomography (OCT). Observational case-control study. Ninety-three subjects were recruited from the longitudinal University of California, San Diego, Diagnostic Innovations in Glaucoma Study. All participants had > or =2 reliable SAP-Swedish Interactive Testing Algorithm and FDT 24-2 tests and at least one Stratus OCT test, all conducted within a 6-month time window. Retinal nerve fiber layer thickness measured with OCT and the number of sectors with OCT-measured RNFL thickness lower than the 95% confidence interval (CI) or 99% CI based on the instrument's normative database. Compared with those with normal SAP and FDT results, a significantly higher proportion of subjects with normal SAP and abnormal FDT results had OCT-measured RNFL thickness outside 95% limits in the inferior and superior quadrants (P = 0.048) and outside 99% limits in the inferior quadrant (P = 0.010). When SAP is within normal range, some patients with VF loss detected by FDT show a decreased RNFL thickness, possibly indicating the presence of glaucomatous damage. These results support the validity of FDT as a tool to detect early glaucoma.

Frequency Doubling Technology Perimetry in Open-angle Glaucoma Eyes With Hemifield Visual Field Damage: Comparison of High-tension and Normal-tension Groups

To evaluate the performance of frequency doubling technology (FDT) perimetry in open-angle glaucoma eyes with hemifield visual field damage and to compare it between open-angle glaucoma with high pressure [high-tension glaucoma (HTG)] and those with normal pressure [normal-tension glaucoma (NTG)] groups. FDT perimetry with the N-30 full threshold protocol and standard automated perimetry (SAP) using the Humphrey Field Analyzer with the 30-2 full threshold protocol were performed in 20 eyes of 20 HTG patients and 36 eyes of 36 NTG patients with visual field damage confirmed with SAP in only one hemifield. There was no significant difference in demographics, the Heidelberg Retina Tomography indices, and the Humphrey Field Analyzer indices between HTG and NTG groups. Regarding the FDT perimetry results, mean deviation in the global field (P=0.009) and mean sensitivity in the SAP-spared (P=0.001) and SAP-impaired (P=0.011) hemifields were lower; the numbers of FDT abnormal test points (probability of abnormality <5%) in the SAP-spared hemifield were significantly greater (P=0.005) in HTG than in NTG groups. Eyes in which FDT results of the SAP-spared hemifield were judged as abnormal was more frequent in HTG groups (P=0.007). The performance of FDT perimetry to detect early or preperimetric glaucomatous functional changes should be different between HTG and NTG eyes.

Effect of Cataract on Frequency Doubling Perimetry in the Screening Mode

To determine the effect of cataract on frequency doubling perimetry in the screening mode. Frequency doubling technology perimetry in the C-20-5 screening mode was performed prospectively on 34 patients with otherwise healthy eyes before and after phacoemulsification. Cataracts were scored using the LOCS III classification, and the number of missed points (at any level of severity) on the screening field was compared before and after surgery. Nine patients missed at least one point pre-operatively and had no misses post-operatively. Those patients with posterior subcapsular (PSC) cataract were significantly more likely to miss points on the screening frequency doubling technology perimetry than those without posterior subcapsular cataracts (P < 0.001; Fisher exact test). In addition, the degree of posterior subcapsular cataract strongly correlated with the number of missed points pre-operatively (r = 0.97). The degree of nuclear sclerotic cataract did not correlate strongly with the number of missed points (r = 0.26), but the correlation was slightly stronger in the presence of cortical cataract (r = 0.36). Advanced age-related cataracts may cause false positive results on the screening frequency doubling technology, and the presence of even mild posterior subcapsular cataract may be a cause of false positive results and should be taken into consideration when interpreting the screening frequency doubling technology perimetry results.

Short wavelength automated perimetry, frequency doubling technology perimetry, and pattern electroretinography for prediction of progressive glaucomatous standard visual field defects

Purpose To evaluate the clinical use of a test battery of short wavelength automated perimetry (SWAP), frequency doubling technology perimetry (FDT), and pattern electroretinography (PERG) in predicting progressive glaucomatous visual field defects on standard automated perimetry (SAP). Study design A prospective, longitudinal, observational case series. Participants One hundred and fifty-two patients with primary open-angle glaucoma (POAG) with bilateral glaucomatous visual field defects on SAP were followed at 6-month intervals over a period of 30 months. Main outcome measures Short wavelength automated perimetry, FDT, and PERG results were compared between POAG eyes with and without progressive field loss on SAP. These two groups were used to evaluate whether PERG, SWAP, and/or FDT is predictive of future progression of field loss on SAP. Results Using the criteria of progressive field loss on SAP defined by the Collaborative Normal Tension Glaucoma Study, 54 eyes (study group) of 54 POAG patients showed progressive defects, whereas 84 eyes (control group) of 84 POAG patients showed no progression. Only 11.1% (6 of 54) of the eyes with a progression of field loss on SAP showed no increase of deficits on the three functional tests before progression. Short wavelength automated perimetry detected early progressive defects on SAP in 43 of the 54 eyes (79.6%). Of these 54 POAG eyes, FDT showed progressive deficits in 40 eyes (74.1%), whereas PERG amplitude P1N2 showed progressive deficits in 35 eyes (64.8%) before progression of field loss on SAP. A test battery consisting of SWAP and PERG P1N2-amplitude was able to detect 88.9% of eyes before a prediction of field loss on SAP. When comparing the results of the two functional tests, SWAP and FDT in the 84 eyes without progression of field loss on SAP between baseline and at 30 months, SWAP and FDT showed progressive deficits in 34.5% and 35.7%, respectively. Conclusions All three tests (SWAP, FDT, and PERG) have been successful in detecting glaucoma eyes with a future progression of standard visual field defects. A test battery of SWAP and PERG P1N2-amplitude improved the power to predict these progressive defects on SAP. It remains to be seen whether the long-term follow-up in POAG eyes will improve the false-positive rate of SWAP and FDT.