Central visual function and inner retinal structure in primary open-angle glaucoma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

To investigate associations between central visual function and inner retinal structure in primary open-angle glaucoma (POAG). This study enrolled 78 POAG patients and 58 healthy controls. POAG was classified into early glaucoma and moderate to advanced glaucoma. The following tests were performed on all participants: isolated-check visual evoked potential (icVEP) testing, 24-2 standard automated perimetry (SAP), and Cirrus optical coherence tomography (OCT) examinations. Signal-to-noise ratio (SNR) measures obtained from icVEP responses to isolated checks presented at four depths of modulation (DOMs; 8%, 14%, 22%, and 32%) were explored. Mean macular sensitivity (mMS) was assessed by calculating the mean sensitivities of central 12 SAP points. Ganglion cell layer+ inner plexiform layer thickness (GCL+IPLT) and peripapillary retinal nerve fiber layer thickness (pRNFLT) were measured by OCT scanning. For each group of subjects, linear relationships among the following measures were analyzed: SNR, mMS, GCL+IPLT, and pRNFLT. SNR, mMS, GCL+IPLT, and pRNFLT were all more significantly decreased in glaucoma than in controls (P<0.001). A significant positive association was found between SNR at 14% DOM and GCL+IPLT at the inferior sector in early glaucoma (r=0.465, P=0.004). In moderate to advanced glaucoma, significant correlations were found between SNR at 32% DOM and mean GCL+IPLT (r=0.364, P=0.023), superior GCL+IPLT (r=0.358, P=0.025), and mean pRNFLT (r=0.396, P=0.025). In addition, in moderate to advanced glaucoma, there were significant correlations between mMS and all relevant measures of retinal thickness (r=0.330-0.663, P< 0.010). In early glaucoma, significant correlations were found between mean mMS and minimum GCL+IPLT (r=0.373, P=0.023), and between inferior mMS and superior GCL+IPLT (r=0.470, P=0.003). Linear models provided a good explanation for the relationship between SNR and inner retinal thickness (IRT), whereas nonlinear models better explained the relationship between mMS and IRT. In early glaucoma, both SNR and mMS were related moderately and significantly to IRT, whereas in moderate to advanced glaucoma, mMS was more strongly correlated with IRT than SNR.

Structure-function correlation of juxtapapillary choroidal thickness with visual field analysis of patients suspected with glaucoma

Purpose@#To conduct an evaluation of juxtapapillary choroidal thickness of patients suspected with glaucoma obtained through spectral domain optical coherence tomography (SD-OCT) and correlate it with perimetry results.@*Methods@#Design: Cross-sectional Study. Population: 175 eyes diagnosed as “glaucoma suspect” had standard automated perimetry (SAP) to document the presence of functional glaucomatous damage using optimal near-point correction using the Humphrey Visual Field Analyzer II, 30-2 or 24-2 SITA-standard program. SD-OCT imaging of the retinal nerve fi ber layer (RNFL) was also done to look for structural glaucomatous damage and in using enhanced depth imaging of the optic nerve and the Cirrus caliper tool, choroidal thickness was measured at fi ve predetermined points temporal and nasal from the optic nerve. The population was classifi ed into two groups: Group 1 are those with structural or functional glaucomatous damage (n=68) and Group 2 were those without (n=107).@*Results@#One-Way Multivariate Analysis of Covariance was used in comparing the mean temporal and nasal choroidal thickness scores of the two groups. There are no statistical differences in terms of the mean temporal choroidal thickness (p=0.856) and mean nasal choroidal thickness (p=0.734) between patients with and without glaucomatous damage. The mean temporal and nasal choroidal thickness scores of the two groups at different juxtapapillary locations: 0 μm, 250 μm, 500 μm, 750 μm and 1000 μm away from the disc were also not statistically different.@*Conclusion@#Results show that from this present cohort of glaucoma suspect patients, juxtapapillary choroidal thickness is not correlated with structural and functional glaucomatous damage.

Central visual function and inner retinal structure in primary open-angle glaucoma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

To investigate associations between central visual function and inner retinal structure in primary open-angle glaucoma (POAG). This study enrolled 78 POAG patients and 58 healthy controls. POAG was classified into early glaucoma and moderate to advanced glaucoma. The following tests were performed on all participants: isolated-check visual evoked potential (icVEP) testing, 24–2 standard automated perimetry (SAP), and Cirrus optical coherence tomography (OCT) examinations. Signal-to-noise ratio (SNR) measures obtained from icVEP responses to isolated checks presented at four depths of modulation (DOMs; 8%, 14%, 22%, and 32%) were explored. Mean macular sensitivity (mMS) was assessed by calculating the mean sensitivities of central 12 SAP points. Ganglion cell layer+ inner plexiform layer thickness (GCL+IPLT) and peripapillary retinal nerve fiber layer thickness (pRNFLT) were measured by OCT scanning. For each group of subjects, linear relationships among the following measures were analyzed: SNR, mMS, GCL+IPLT, and pRNFLT. SNR, mMS, GCL+IPLT, and pRNFLT were all more significantly decreased in glaucoma than in controls (P<0.001). A significant positive association was found between SNR at 14% DOM and GCL+IPLT at the inferior sector in early glaucoma (r=0.465, P=0.004). In moderate to advanced glaucoma, significant correlations were found between SNR at 32% DOM and mean GCL+IPLT (r=0.364, P=0.023), superior GCL+IPLT (r=0.358, P=0.025), and mean pRNFLT (r=0.396, P=0.025). In addition, in moderate to advanced glaucoma, there were significant correlations between mMS and all relevant measures of retinal thickness (r=0.330−0.663, P<0.010). In early glaucoma, significant correlations were found between mean mMS and minimum GCL+IPLT (r=0.373, P=0.023), and between inferior mMS and superior GCL+IPLT (r=0.470, P=0.003). Linear models provided a good explanation for the relationship between SNR and inner retinal thickness (IRT), whereas nonlinear models better explained the relationship between mMS and IRT. In early glaucoma, both SNR and mMS were related moderately and significantly to IRT, whereas in moderate to advanced glaucoma, mMS was more strongly correlated with IRT than SNR.

Development of an LCD-Based Visual Field System

BACKGROUND: The present study investigated the diagnostic effectiveness of an LCD-based visual field testing system (LVF) in comparison with the standard automated perimetry Humphrey Field Analyzer II-750i (HFA). METHODS: A randomized controlled crossover study was conducted with 202 normal and 128 glaucomatous eyes using both LVF and HFA. The visual field testing systems were compared in terms of mean deviation (MD), pattern standard deviation (PSD), and area under the receiver operating characteristics curve (AUC) of MD and PSD differentiating the normal and glaucomatous eyes. RESULTS: Significant correlations were found between MD measurements from LVF and those from HFA for normal eyes (r = 0.342) and glaucomatous eyes (r = 0.796); slightly higher significant correlations were identified between PSD measurements from LVF and those from HFA for normal eyes (r = 0.363) and glaucomatous eyes (r = 0.828). Furthermore, high AUCs of MD were found as 0.786 for LVF and 0.868 for HFA and AUCs of PSD as 0.913 for LVF and 0.932 for HFA. CONCLUSION: The comparison results of the present study support the competence of LVF compared with HFA in visual field testing for early detection of glaucoma.

Functional MRI Characteristics in Visual Cortex (BA 17, 18 and 19) Corresponding to the Visual Field of Normal, Glaucoma Suspect (GS) and Primary Open Angle Glaucoma (POAG) Patients / Jurnal Sains Kesihatan Malaysia

The purpose of this study was to characterize, differentiate and correlate visual field and brain activation in visual cortex for normal, glaucoma suspect (GS) and primary open angle glaucoma (POAG) participants using Standard Automated Perimetry (SAP) and functional Magnetic Resonance Imaging (fMRI) respectively. The fMRI scans and SAP test were both carried out in Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM). Two types of black-and-white checkerboard pattern were displayed to the participants during the fMRI scans. The fMRI data were analyzed using WFU pickatlas toolbox targeting visual cortex area. The results showed that there was no significant difference in number of activated voxel between the three groups in visual cortex (BA 17, 18 and 19) while viewing all the given stimuli (p > 0.05). The pattern standard deviation (PSD) of SAP for visual field also revealed no significant differences (p > 0.05) in all groups of participants. However, negative correlation between PSD and fMRI activation was observed. The PSD values increased with a decrease in fMRI activation. With reference to visual field analysis, the results suggest that glaucomatous neuropathy of POAG patients has led to a gradual decrease in visual cortex activation and a gradual increase in PSD.

Detecting the Progression of Normal Tension Glaucoma: A Comparison of Perimetry, Optic Coherence Tomography, and Heidelberg Retinal Tomography

PURPOSE: We compared the abilities of Stratus optical coherence tomography (OCT), Heidelberg retinal tomography (HRT) and standard automated perimetry (SAP) to detect the progression of normal tension glaucoma (NTG) in patients whose eyes displayed localized retinal nerve fiber layer (RNFL) defect enlargements. METHODS: One hundred four NTG patients were selected who met the selection criteria: a localized RNFL defect visible on red-free fundus photography, a minimum of five years of follow-up, and a minimum of five reliable SAP, Stratus OCT and HRT tests. Tests which detected progression at any visit during the 5-year follow-up were identified, and patients were further classified according to the state of the glaucoma using the mean deviation (MD) of SAP. For each test, the overall rates of change were calculated for parameters that differed significantly between patients with and without NTG progression. RESULTS: Forty-seven (45%) out of 104 eyes displayed progression that could be detected by red-free fundus photography. Progression was detected in 27 (57%) eyes using SAP, 19 (40%) eyes using OCT, and 17 (36%) eyes using HRT. In early NTG, SAP detected progression in 44% of eyes, and this increased to 70% in advanced NTG. In contrast, OCT and HRT detected progression in 50 and 7% of eyes during early NTG, but only 30 and 0% of eyes in advanced NTG, respectively. Among several parameters, the rates of change that differed significantly between patients with and without progression were the MD of SAP (p = 0.013), and the inferior RNFL thickness (p = 0.041) and average RNFL thickness (p = 0.032) determined by OCT. CONCLUSIONS: SAP had a higher detection rate of NTG progression than other tests, especially in patients with advanced glaucoma, when we defined progression as the enlargement of a localized RNFL defect. The rates of change of the MD of SAP, inferior RNFL thickness, and average RNFL thickness differed between NTG patients with and without progression.

Short wavelength automated perimetry can detect visual field changes in diabetic patients without retinopathy.

Purpose: The purpose of the following study is to compare short wave automated perimetry (SWAP) versus standard automated perimetry (SAP) for early detection of diabetic retinopathy (DR). Materials and Methods: A total of 40 diabetic patients, divided into group I without DR (20 patients = 40 eyes) and group II with mild non‑proliferative DR (20 patients = 40 eyes) were included. They were tested with central 24‑2 threshold test with both shortwave and SAP to compare sensitivity values and local visual field indices in both of them. A total of 20 healthy age and gender matched subjects were assessed as a control group. Results: Control group showed no differences between SWAP and SAP regarding mean deviation (MD), corrected pattern standard deviation (CPSD) or short fluctuations (SF). In group I, MD showed significant more deflection in SWAP (−4.44 ± 2.02 dB) compared to SAP (−0.96 ± 1.81 dB) (P = 0.000002). However, CPSD and SF were not different between SWAP and SAP. In group II, MD and SF showed significantly different values in SWAP (−5.75 ± 3.11 dB and 2.0 ± 0.95) compared to SAP (−3.91 ± 2.87 dB and 2.86 ± 1.23) (P = 0.01 and 0.006 respectively). There are no differences regarding CPSD between SWAP and SAP. The SWAP technique was significantly more sensitive than SAP in patients without retinopathy (p), but no difference exists between the two techniques in patients with non‑proliferative DR. Conclusion: The SWAP technique has a higher yield and efficacy to pick up abnormal findings in diabetic patients without overt retinopathy rather than patients with clinical retinopathy.

Diagnostic Abilities to Detect Glaucomatous Abnormality Using Normal Retinal Thickness Measured by Optical Coherence Tomography

PURPOSE: Recently, the introduction of spectral-domain optical coherence tomography (SD-OCT) has enabled measurement of retinal thickness in the posterior pole in 64 sectors. SD-OCT was used to evaluate the diagnostic effectiveness in detecting glaucomatous abnormality of visual field sensitivity. A normal value for retinal thickness was determined and then compared in corresponding local sectors. METHODS: Thirty healthy controls and 30 glaucoma subjects were evaluated. Macular thickness values from the 4 adjacent square cells in an 8 x 8 posterior pole retinal thickness map were averaged for a mean retinal thickness (MRT) value. A normative database was prepared using the data from the healthy eyes of this study to determine the diagnostic criteria for MRT. If the MRT value was <5% (Criteria A) or <1% (Criteria B) of the normative database, it was considered to be abnormal. The abnormalities of the MRT value for each diagnostic criteria were compared with the visual field sensitivity results in the corresponding positions. RESULTS: The concordance of abnormalities between MRT and visual field sensitivity at 16 measured points was low in both criteria A (Kappa value; -0.418~0.429) and B (Kappa value; -0.363~0.444). Based on the results of the visual field at each focal point, the sensitivities and specificities of MRT values using the 2 criteria ranged from 0% to 100%. CONCLUSIONS: In this study, MRT values showed low correlation and diagnostic ability to detect decreased sensitivity of the visual field in corresponding points, when customized criteria derived from a normative database were applied.

Evaluation of Hemifield Sector Analysis Protocol in Multifocal Visual Evoked Potential Objective Perimetry for the Diagnosis and Early Detection of Glaucomatous Field Defects

PURPOSE: Multifocal visual evoked potential (mfVEP) is a newly introduced method used for objective visual field assessment. Several analysis protocols have been tested to identify early visual field losses in glaucoma patients using the mfVEP technique, some were successful in detection of field defects, which were comparable to the standard automated perimetry (SAP) visual field assessment, and others were not very informative and needed more adjustment and research work. In this study we implemented a novel analysis approach and evaluated its validity and whether it could be used effectively for early detection of visual field defects in glaucoma. METHODS: Three groups were tested in this study; normal controls (38 eyes), glaucoma patients (36 eyes) and glaucoma suspect patients (38 eyes). All subjects had a two standard Humphrey field analyzer (HFA) test 24-2 and a single mfVEP test undertaken in one session. Analysis of the mfVEP results was done using the new analysis protocol; the hemifield sector analysis (HSA) protocol. Analysis of the HFA was done using the standard grading system. RESULTS: Analysis of mfVEP results showed that there was a statistically significant difference between the three groups in the mean signal to noise ratio (ANOVA test, p < 0.001 with a 95% confidence interval). The difference between superior and inferior hemispheres in all subjects were statistically significant in the glaucoma patient group in all 11 sectors (t-test, p < 0.001), partially significant in 5 / 11 (t-test, p < 0.01), and no statistical difference in most sectors of the normal group (1 / 11 sectors was significant, t-test, p < 0.9). Sensitivity and specificity of the HSA protocol in detecting glaucoma was 97% and 86%, respectively, and for glaucoma suspect patients the values were 89% and 79%, respectively. CONCLUSIONS: The new HSA protocol used in the mfVEP testing can be applied to detect glaucomatous visual field defects in both glaucoma and glaucoma suspect patients. Using this protocol can provide information about focal visual field differences across the horizontal midline, which can be utilized to differentiate between glaucoma and normal subjects. Sensitivity and specificity of the mfVEP test showed very promising results and correlated with other anatomical changes in glaucoma field loss.

Evaluation of Hemifield Sector Analysis Protocol in Multifocal Visual Evoked Potential Objective Perimetry for the Diagnosis and Early Detection of Glaucomatous Field Defects

PURPOSE: Multifocal visual evoked potential (mfVEP) is a newly introduced method used for objective visual field assessment. Several analysis protocols have been tested to identify early visual field losses in glaucoma patients using the mfVEP technique, some were successful in detection of field defects, which were comparable to the standard automated perimetry (SAP) visual field assessment, and others were not very informative and needed more adjustment and research work. In this study we implemented a novel analysis approach and evaluated its validity and whether it could be used effectively for early detection of visual field defects in glaucoma. METHODS: Three groups were tested in this study; normal controls (38 eyes), glaucoma patients (36 eyes) and glaucoma suspect patients (38 eyes). All subjects had a two standard Humphrey field analyzer (HFA) test 24-2 and a single mfVEP test undertaken in one session. Analysis of the mfVEP results was done using the new analysis protocol; the hemifield sector analysis (HSA) protocol. Analysis of the HFA was done using the standard grading system. RESULTS: Analysis of mfVEP results showed that there was a statistically significant difference between the three groups in the mean signal to noise ratio (ANOVA test, p < 0.001 with a 95% confidence interval). The difference between superior and inferior hemispheres in all subjects were statistically significant in the glaucoma patient group in all 11 sectors (t-test, p < 0.001), partially significant in 5 / 11 (t-test, p < 0.01), and no statistical difference in most sectors of the normal group (1 / 11 sectors was significant, t-test, p < 0.9). Sensitivity and specificity of the HSA protocol in detecting glaucoma was 97% and 86%, respectively, and for glaucoma suspect patients the values were 89% and 79%, respectively. CONCLUSIONS: The new HSA protocol used in the mfVEP testing can be applied to detect glaucomatous visual field defects in both glaucoma and glaucoma suspect patients. Using this protocol can provide information about focal visual field differences across the horizontal midline, which can be utilized to differentiate between glaucoma and normal subjects. Sensitivity and specificity of the mfVEP test showed very promising results and correlated with other anatomical changes in glaucoma field loss.

Comparison of visual field test results obtained through Humphrey matrix frequency doubling technology perimetry versus standard automated perimetry in healthy children.

Aims: The aim of this study was to compare the visual field test results in healthy children obtained via the Humphrey matrix 24‑2 threshold program and standard automated perimetry (SAP) using the Swedish interactive threshold algorithm (SITA)‑Standard 24‑2 test. Materials and Methods: This prospective study included 55 healthy children without ocular or systemic disorders who underwent both SAP and frequency doubling technology (FDT) perimetry visual field testing. Visual field test reliability indices, test duration, global indices (mean deviation [MD], and pattern standard deviation [PSD]) were compared between the 2 tests using the Wilcoxon signed‑rank test and paired t‑test. The performance of the Humphrey field analyzer (HFA) 24‑2 SITA‑standard and frequency‑doubling technology Matrix 24‑2 tests between genders were compared with Mann‑Whitney U‑test. Results: Fifty‑five healthy children with a mean age of 12.2 ± 1.9 years (range from 8 years to 16 years) were included in this prospective study. The test durations of SAP and FDT were similar (5.2 ± 0.5 and 5.1 ± 0.2 min, respectively, P = 0.651). MD and the PSD values obtained via FDT Matrix were significantly higher than those obtained via SAP (P < 0.001), and fixation losses and false negative errors were significantly less with SAP (P < 0.05). A weak positive correlation between the two tests in terms of MD (r = 0.352, P = 0.008) and PSD (r = 0.329, P = 0.014) was observed. Conclusion: Children were able to complete both the visual test algorithms successfully within 6 min. However, SAP testing appears to be associated with less depression of the visual field indices of healthy children. FDT Matrix and SAP should not be used interchangeably in the follow‑up of children.

The role of standard automated perimetry and newer functional methods for glaucoma diagnosis and follow-up.

Automated perimetry has become the mainstream for assessment of functional glaucomatous loss and progressive damage. Recent improvements with the Swedish interactive thresholding algorithm (SITA) strategy and the guided progression analysis (GPA) have further settled standard achromatic perimetry (SAP) as the preferred method for diagnosis and follow-up of functional loss. Although SAP is still considered the gold standard, function-specific perimetry may offer advantages for early diagnosis. Frequency doubling technology (FDT) and short-wavelength automated perimetry (SWAP) have been shown to be helpful, especially when SAP is normal and there is a suspicion of glaucoma. Studies using rarebit perimetry have also shown promising results. Studies have observed that each test identifies a different subset of eyes, and combining the tests may improve sensitivity. Nevertheless, the more sophisticated analyses do not reduce the importance of a correct interpretation of the test results.

Comparison of Total Deviation of Standard Automated Perimetry and Matrix FDT in Preperimetric Glaucoma Patients

PURPOSE: To compare the results of total deviation (TD) as measured by standard automated perimetry (SAP) and measured with of Matrix Frequency-doubling Technology (FDT) in patients with preperimetric glaucoma. METHODS: Fifty-two eyes of 52 patients with preperimetric glaucoma were included. Subjects were examined with Matrix FDT and Stratus optical coherence tomography (OCT), and the results of each examination were analyzed. The proportions of abnormal results in SAP TD, Matrix TD, and Matrix pattern deviation (PD) were calculated. Among the results of tests, the following correlations were evaluated: SAP TD and Matrix, and visual fields and OCT. In addition, the differences in peripapillary retinal nerve fiber layer thickness (RNFL) according to the result of SAP TD in preperimetric patients with abnormal Matrix PD were analyzed. RESULTS: A abnormalities in SAP TD, Matrix TD and Matrix PD were found in 22 (42.3%), 34 (65.4%), 41 (78.9%) eyes, respectively. There was marginal correlation between SAP TD and Matrix PD (p=0.07). No significant correlation was found between SAP TD and OCT, although Matrix PD and OCT did show significant correlation (p<0.05). In preperimetric patients with abnormal Matrix PD, RNFL thickness was significantly lower in the abnormal SAP TD group than in the normal SAP TD group on average, in the superior quadrant, and at the 12 o'clock and 5 o'clock positions (p<0.05). CONCLUSIONS: In patients with preperimetric glaucoma, 42.3% and 78.9% had glaucomatous VF defects in SAP TD and Matrix PD, respectively. These results were higher than expected, especially those of SAP TD.

The Comparison of The Matrix Perimetry and Humphrey Standard Perimetry in Various Patients Group

PURPOSE: To study the correlation between the Humphrey standard automated perimetry (SAP) and the Humphrey Matrix Frequency Doubling Technology (FDT) perimetry and diagnostic usefulness of the Humphrey Matrix FDT perimetry. METHODS: This study included 170 eyes of 170 patients. The 170 eyes were classified into 50 normal eyes, 20 ocular hypertensive eyes, 50 glaucoma-suspect eyes and 50 glaucomatous eyes. All subjects were examined with the Humphrey Matrix perimetry and the Humphrey standard automated perimetry. We studied the correlations between mean deviation (MD) and pattern standard deviation(PSD) of the Humphrey SAP and those of the Humphrey Matrix perimetry, respectively, in each of the classified group. RESULTS: Overall, MD and PSD of the Humphrey SAP were significantly correlated with MD and PSD of the Humphrey Matrix perimetry, respectively. However, MD and PSD of the Humphrey Matrix perimetry were not showed a significant correlation in normal subjects (P>0.05). CONCLUSIONS: In this study, there were significant correlations between the MD and PSD of the SAP and those of the Humphrey Matrix perimetry in glaucoma, glaucoma-suspect and ocular hypertension. These finding suggests the Humphrey Matrix perimetry has performance characteristics similar to SAP and diagnostic value.