Short-wavelength Automated Perimetry Research Articles

Can Frequency-doubling Technology and Short-wavelength Automated Perimetries Detect Visual Field Defects Before Standard Automated Perimetry in Patients With Preperimetric Glaucoma?

To assess the ability of frequency-doubling technology (FDT) perimetry and short-wavelength automated perimetry (SWAP) to detect glaucomatous damage in preperimetric glaucoma subjects. Two hundred seventy-eight eyes of 278 subjects categorized as normal eyes [n=98; intraocular pressure <20 mm Hg, normal optic disc appearance, and standard automated perimetry (SAP)]; preperimetric glaucoma eyes (n=109; normal SAP and retinal nerve fiber layer defects or localized optic disc notching and thinning); and glaucoma patients (n=71; intraocular pressure >21 mm Hg, optic disc compatible with glaucoma, and abnormal SAP). The preperimetric glaucoma group underwent at least 2 reliable full-threshold 24-2 Humphrey SAPs, full-threshold C-20 FDT, full-threshold 24-2 SWAP, optic disc topography using the Heidelberg Retina Tomograph II, laser polarimetry using the GDx VCC, and Optical Coherence Tomography (Zeiss Stratus OCT 3000). Receiver operating characteristic curves were plotted for the main Heidelberg Retina Tomograph, Optical Coherence Tomography, and GDx VCC parameters for the normal and glaucoma patients. The area under the receiver operating characteristic curve was used to determine the parameters indicating glaucomatous damage in the optic disc or retinal nerve fiber layer, which were used to establish additional subgroups of patients with preperimetric glaucoma. FDT and SWAP sensitivities were calculated for the patient subsets with structural damage and normal SAP. At least 20% of the patients with preperimetric glaucoma demonstrated functional losses in FDT and SWAP. The more severe the structural damage, the greater the sensitivity for detecting glaucomatous visual field losses. FDT and SWAP detect functional losses in cases of suspected glaucoma before glaucomatous losses detected by SAP.

Frequency Doubling Perimetry and Short-Wavelength Automated Perimetry to Detect Early Glaucoma

To compare the ability of short-wavelength automated perimetry (SWAP) and frequency doubling perimetry (FDP) to detect early glaucoma damage. Prospective case-control study using a comparative case series. Forty-two patients with preperimetric glaucomatous optic nerve damage and a normal standard achromatic perimetry (SAP) in 1 eye, but with contralateral SAP abnormalities, and 35 normals. Forty-two patients and 35 normals underwent SWAP and FDP (Humphrey 24-2; Carl Zeiss Meditec, Inc., Dublin, CA). Correlations of mean deviation (MD) and pattern standard deviation (PSD) of the 2 groups were calculated. The number of defects at P<0.05 and P<0.01 on total deviation (TD) and pattern deviation (PD) plots were compared. Diagnostic precision and agreement on location of abnormalities were determined. Correlations and comparisons of global indices between SWAP and FDP: MD, PSD, TD, and PD abnormal number of points. Significant correlations in the glaucoma group were found between SWAP and FDP for MD (r = 0.54; P<0.008) and PSD (r = 0.49; P<0.001). Defects on the TD and PD plots were detected more frequently by FDP in the glaucoma group, although they were significant only for PD at P<0.01 (P = 0.024). Areas under receiver operator characteristic curves for MD of SWAP and PSD of FDP were 0.74 and 0.67, respectively (P = 0.37). Using defined defect criteria, FDP had a significantly higher sensitivity (72% vs. 54%; P = 0.02) and similar specificity (53% vs. 44%; P = 0.12) compared with SWAP. Agreement on defect location was moderate (kappa, 0.46). Testing time for SWAP was longer than for FDP in both glaucomatous and normal eyes (P<0.001). Short-wavelength automated perimetry and FDP showed similar ability to detect visual dysfunction in patients with preperimetric glaucoma. Long-term follow-up is required to define their role in predicting subsequent SAP defects.

Influence of blue light spectrum filter on short-wavelength and standard automated perimetries

To evaluate the influence of a blue light spectrum filter (BLSF), similar in light spectrum transmittance to the intraocular lens Acrysof Natural, on standard automated perimetry (SAP) and short-wavelength automated perimetry (SWAP). Twenty young individuals (< 30 y.o.), without any systemic or ocular alterations (twenty eyes) underwent a random sequence of four Humphrey visual field tests: standard automated perimetry (SAP) and short-wavelength automated perimetry (SWAP) with and without a blue light spectrum filter. All patients had intraocular pressure lower than 21 mmHg, normal fundus biomicroscopy, and no crystalline lens opacity. Foveal threshold (FT), mean deviation (MD), and pattern standard deviation (PSD) indexes obtained from the visual field tests and the difference caused by eccentricity in short-wavelength automated perimetry examinations were analyzed using paired t test. Interindividual variability (standard deviation) was calculated using Pitman's test for correlated samples. Statistically significant reductions in the mean deviation (p < 0.001) and in the foveal threshold (p < 0.001) measured by short-wavelength automated perimetry with the use of the blue light spectrum filter in comparison to short-wavelength automated perimetry without the use of the blue light spectrum filter were observed, but not in standard automated perimetry exams. No other parameters showed statistically significant differences in the short-wavelength automated perimetry and standard automated perimetry tests. Interindividual standard deviation of the test points in the short-wavelength automated perimetry exams increased with eccentricity both with and without the use of the blue light spectrum filter, as sensitivity for inferior and superior hemifields (inferior hemifield minus superior hemifield), but no statistically significant difference in the variability when comparing the use or not of the blue light spectrum filter was noted. When comparing only the four most inferior points and the four most superior points, the inferior-superior difference increases in both situations - without and with the use of the blue light spectrum filter. The difference between without and with the use of the blue light spectrum filter was not statistically significant. Statistically significant reductions in mean deviation and foveal threshold in the short-wavelength automated perimetry with the use of the blue light spectrum filter were observed, but not in standard automated perimetry examinations. Additional studies are necessary to determine the influence of intraocular lenses with short-wavelength light filter after cataract extraction on short-wavelength automated perimetry.

Learning Effect of Short-wavelength Automated Perimetry in Patients With Ocular Hypertension

To evaluate the learning effect of short-wavelength automated perimetry (SWAP) on a group of patients with ocular hypertension experienced with standard automated perimetry (SAP). Thirty patients with ocular hypertension underwent 5 full-threshold SWAP tests at intervals of 7+/-2 days. The parameters investigated to detect a learning effect were duration, the perimetric indices, and the number of points with a P of <5% and 1% in the total and pattern deviation maps. Differences in learning effect were also evaluated by comparing the sensitivities of central, paracentral, and peripheral areas, hemifields and quadrants. Learning effects were demonstrated for mean defect (P<0.0001, analysis of variance), duration (P=0.0001), the number of points with P<5% in the pattern deviation map (P=0.003), and short fluctuations (P=0.03). The effect was greater in the peripheral than in central areas (P=0.04). Mean defect was the most sensitive parameter, for which the learning effect was statistically significant between the first and the fifth test. The results of this study demonstrate a significant learning effect at full-threshold SWAP. This may limit the efficacy of this kind of perimetry in detecting early glaucoma, and should therefore be carefully considered when creating normative databases for new SWAP strategies.

Capacidad diagnóstica del stratus OCT para detectar glaucomas pre-perimétricos

To compare retinal nerve fiber layer (RNFL) measurements performed with Stratus OCT 3000 in normal, ocular hypertensive, pre-perimetric and glaucomatous eyes. 98 normal subjects, 156 ocular hypertensives with short-wavelength automated perimetry (SWAP), 21 ocular hypertensives with altered SWAP (pre-perimetric glaucoma) and 66 glaucomatous eyes were included in the study. Diagnostic groups were classified based on intraocular pressure, optic nerve head appearance, achromatic automatic perimetry and SWAP. RNFL parameters were obtained using a Stratus OCT 3000 (Humphrey Zeiss instruments). RNFL measurements were compared among the groups. RNFL average thickness, superior, inferior and nasal quadrant thickness, and each 12 clock-hour positions except for H9, H10 and H11 showed significant differences between glaucomatous and pre-perimetric glaucoma eyes. RNFL average thickness, inferior quadrant and H10 clock-hour position showed significant differences between normal and ocular hypertensive subjects. Pre-perimetric glaucomas and ocular hypertensives showed differences in H11 clock-hour position exclusively. RNFL measurements performed using Stratus OCT showed differences between the study groups. OCT may be as useful as SWAP in early glaucoma diagnosis.

Combining Structural and Functional Testing for Detection of Glaucoma

To assess whether the combined use of both structural and functional tests improves discrimination between healthy and glaucomatous eyes over either type of testing alone. Observational cross-sectional study. One hundred twenty-three eyes of 123 participants enrolled in the Diagnostic Innovations in Glaucoma Study. Because both structural and functional tests were evaluated, 2 definitions of glaucoma were used: glaucomatous visual field (VF) damage based on repeatable abnormal standard automated perimetry results (n = 43) and glaucomatous optic disc (glaucomatous optic neuropathy [GON]) based on masked assessment of optic disc stereophotographs (n = 65). Participants had scanning laser polarimetry, optical coherence tomography (OCT), and confocal scanning laser ophthalmoscopy imaging in addition to frequency-doubling technology (FDT) perimetry and short-wavelength automated perimetry (SWAP) testing completed within a 6-month interval. For each glaucoma definition, sensitivities and specificities were calculated for the best structural parameters, FDT perimetry pattern standard deviation (PSD), and SWAP PSD/glaucoma hemifield test, and then for each possible pairwise combination of one structural and one functional parameter. The best structural parameters for discriminating between glaucoma and control eyes were nerve fiber indicator for scanning laser polarimetry, inferior average retinal nerve fiber layer thickness for OCT, and Moorfields regression classification for confocal scanning laser ophthalmoscopy. Sensitivities and specificities for detecting glaucomatous VF damage for scanning laser polarimetry, OCT, confocal scanning laser ophthalmoscopy, FDT perimetry, and SWAP were 41.9% and 98.3%, 58.1% and 98.3%, 58.1% and 84.5%, 44.2% and 98.3%, and 65.1% and 86.2%, respectively. Adding FDT perimetry to each of the best structural parameters led to a significant (P<0.05) increase in sensitivity without a significant change in specificity compared with structural parameters alone. Adding SWAP to each of the best structural parameters led to a significant increase in sensitivity and also a significant decrease in specificity compared with each structural parameter alone. A combination of parameters from structural tests and functional tests can improve the sensitivity of glaucoma detection. The sensitivity and specificity desired for a particular clinical application will determine the selection of the particular diagnostic tests.

Effect of the AcrySof Natural intraocular lens on blue–yellow perimetry

To assess the differences in blue-yellow perimetry values in patients with an AcrySof Natural intraocular lens (IOL) in 1 eye and a conventional AcrySof IOL in the fellow eye. Cataract and glaucoma clinics of a medical school associated with a public hospital in Brazil. Forty-six patients had bilateral phacoemulsification and implantation of an AcrySof SN60AT IOL (Alcon) in 1 eye and an MA30AC IOL (Alcon) in the fellow eye. Blue-yellow perimetry was performed in both eyes, and the data were analyzed in blinded fashion using the Mann-Whitney U test. No statistically significant differences were observed in short-wavelength automated perimetry (SWAP) values between the 2 IOLs. There was no interference by the yellow filter of the AcrySof Natural IOL in blue-yellow perception as determined by SWAP.

Identifying Glaucomatous Vision Loss with Visual-Function–Specific Perimetry in the Diagnostic Innovations in Glaucoma Study

To compare the diagnostic results of four perimetric tests and to identify useful parameters from each for determining abnormality. One hundred eleven eyes with glaucomatous optic neuropathy (GON), 31 with progressive optic neuropathy (PGON) 53 with ocular hypertension, and 51 with no disease were included (N = 246). Visual field results were not used to classify the eyes. Short-wavelength automated perimetry (SWAP), frequency-doubling technology perimetry (FDT), high-pass resolution perimetry (HPRP), and standard automated perimetry (SAP) were performed. Receiver operating characteristic (ROC) curves were used to compute the areas under the curves (AUC) and sensitivity levels at given specificities for a variety of abnormality criteria. The agreement among tests for abnormality, location, and extent of visual field deficit were assessed. AUC analysis: When the normal group was compared with the GON group, the FDT pattern SD (PSD) area was larger than the HPRP PSD (P = 0.020), and the FDT area of total deviation (TD) <5% was larger than the HPRP mean deviation (MD; P = 0.004). When the normal group was compared with the PGON group, the FDT area of pattern deviation (PD) <5% was larger than the SWAP PSD (P = 0.020). A difference from previous work was that AUCs for PSD or the best SAP were not significantly poorer than those in the function-specific tests. At set specificities, FDT yielded higher sensitivities than all other tests for all parameters. The agreement among tests for abnormality was fair to moderate (kappa = 247-0.563). When loss was present on more than one test, the quadrant of the visual field affected was the same in 95% (79/83) of eyes. The number of eyes identified and number of abnormal quadrants increased across groups with increasing certainty of glaucoma. At equal specificity, no single perimetric test was always affected, whereas others remained normal. Several parameters at suggested criterion values provided good sensitivity and specificity. FDT showed the highest sensitivity overall, with SAP performing better than in prior reports. Of note, the same area of the retina was identified as damaged in all tests.

Diagnostic Sensitivity of Fast Blue–Yellow and Standard Automated Perimetry in Early Glaucoma: A Comparison between Different Test Programs

To compare the ability of Fast Swedish interactive threshold algorithm (SITA) short-wavelength automated perimetry (SWAP), lengthier full-threshold SWAP, and standard automated perimetry (SAP) using the SITA Fast program to detect early glaucomatous visual field loss. Cross-sectional prospective study of perimetric diagnostic sensitivity as defined by reference limits determined in the same healthy participants for all 3 test programs. One hundred one patients with ocular hypertension, or suspect or early manifest glaucoma. One eye of each patient was tested with 2 blue-yellow perimetric programs: the SITA and full-threshold SWAP and the SAP SITA Fast program. Glaucomatous visual field loss, defined as number of significantly depressed test point locations or the number of clusters of such test points. No significant difference in number of significantly depressed test point locations between the 3 programs could be detected, neither at the P<5% limit nor at the P<2% limit. The difference in number of points depressed below the fifth percentile was 0.5 between full-threshold SWAP and SITA SWAP, 1.09 between full-threshold SWAP and SAP, and 1.04 between SITA SWAP and SAP. The number of eyes showing clusters of significantly depressed points also was similar with the 3 test programs: full-threshold SWAP identified clusters in 66 eyes, SITA SWAP identified clusters in 67 eyes, and SITA Fast SAP identified clusters in 65 eyes. Average test time was 12.0 minutes using full-threshold SWAP, 4.1 minutes with SITA SWAP, and 3.5 with SITA Fast. The SITA SWAP identified at least as much glaucomatous visual field loss as the older full-threshold SWAP, although test time was considerably reduced. Conventional SAP using SITA Fast was not significantly less sensitive than either of the 2 SWAP programs.

Normal Age-Related Sensitivity Loss for a Variety of Visual Functions Throughout the Visual Field

The purpose of this study is to compare the rate of age-related decline, the magnitude of practice effects, and test-retest variability among normal subjects using six different tests of visual function. One hundred normal subjects aged between 20 and 85 were enrolled in the study. Six visual field test procedures were used consisting of standard automated perimetry (SAP), short wavelength automated perimetry (SWAP), temporal modulation perimetry (TMP), frequency-doubling technology perimetry (FDT), detection acuity perimetry (DAP),and resolution acuity perimetry (RAP). To facilitate direct comparison, the results for each test were divided by that test's estimated dynamic range. Of the three tests used clinically most commonly, SWAP exhibited the greatest aging and practice effects and test-retest variability followed by FDT with SAP exhibiting the least. RAP was the most variable test followed by TMP. These results should be taken into account when evaluating glaucomatous loss using different functional tests and when comparing the performance, predictive power, and speed of detection of the different tests.

Agreement of the Heidelberg Retina Tomograph II Macula Edema Module With Fundus Biomicroscopy in Diabetic Maculopathy

To estimate the agreement between the macular edema maps (MEMs) of the Retina Module of the Heidelberg Retina Tomograph II (Heidelberg Engineering, Heidelberg, Germany) and contact lens fundus biomicroscopy (FB) and to assess the influence of combining MEM data with the results of short-wavelength automated perimetry (SWAP) and fluorescein angiography (FA) on diagnostic test performance. Prospective, observational case series. Twenty patients (20 eyes) with diabetic retinopathy with or without clinically manifest macular edema (11 and 9 eyes, respectively) were enrolled. All patients underwent full ophthalmologic examination and also MEM assessment, SWAP, and FA. Using FB as the "gold standard," the agreement between the MEMs and FB was very good (Kendall coefficient of concordance, 0.80). Macular edema maps showed good agreement with FA and SWAP (Kendall coefficient, 0.64 and 0.65). Virtually all of the edematous areas detected with MEM but not seen clinically had decreased sensitivity on SWAP and/or fluorescein leakage. Macular edema maps demonstrated very good agreement with FB. Combining the results of FA and SWAP with those of the MEMs provided supporting evidence of concomitant blood-retinal barrier leakage and visual dysfunction, respectively, in areas of early retinal thickening. Prospective studies are ongoing to fully assess the diagnostic test performance of MEMs in the detection of early and progressive diabetic macular edema.

Diagnostische Möglichkeiten zur Früherkennung der Glaukomprogression

To monitor the efficiency of glaucoma therapy it is necessary to detect progression of the disease as soon as possible. This survey presents the results on functional and morphological approaches to detect glaucoma progression. Risk factors identified in the therapeutic intervention studies should be used to evaluate the possible risk for progression. The functional test approaches of standard achromatic perimetry (SAP), short wavelength automated perimetry (SWAP) and frequency doubling technology (FDT) are described. Furthermore, morphologic changes are described by means of optic nerve head and nerve fiber photography, optic nerve head tomography, optic coherence tomography and nerve fiber polarimetry. The risk factors identified in the interventional studies were as follows: 1. higher intraocular pressure, 2. worse mean deviation (MD), 3. older age, and 4. frequent disc hemorrhages. Additionally, in patients with normal pressure glaucoma, migraine headaches were identified. Patients with ocular hypertension showed a higher risk of conversion into open angle glaucoma in case of higher pattern standard deviation (PSD), thinner central corneal thickness and larger vertical cup-to-disc ratio. The optic nerve head photography was the standard procedure of morphological monitoring in the interventional studies. A direct comparison of the available techniques on nerve fiber thickness and optic nerve head morphology is not yet available. SAP represents the functional methodology with the most validated results. SWAP and FDT showed that progression in early glaucoma can be detected before SAP damage occurs. Glaucoma patients should be regularly tested with SAP and optic nerve head photography. Automated nerve fiber or optic nerve head morphology measuring techniques might be favourable to complete the diagnostic monitoring. In patients without glaucomatous damage SWAP and FDT may be able to detect changes earlier than SAP. The results of a review of the literature are presented and discussed for each technology.

Evidence for a Learning Effect in Short-Wavelength Automated Perimetry

To document the magnitude of any learning effect for short-wavelength automated perimetry (SWAP) in patients with either ocular hypertension (OHT) or open-angle glaucoma (OAG) who are experienced in standard automated perimetry (SAP). Experimental study. Thirty-five patients (22 with OHT and 13 with OAG) who had previously undergone at least 3 threshold SAP visual field examinations with the Humphrey Field Analyzer (HFA; Carl Zeiss Meditech Inc., Dublin, CA), and 9 patients with OHT who had not previously undertaken any form of perimetry. Each patient attended for SWAP on 5 occasions, each separated by 1 week. At each visit, both eyes were examined using Program 24-2 of the HFA; the right eye was always examined before the left eye. (1) Change over the 5 examinations, in each eye, of the visual field indices Mean Deviation (MD), Short-term Fluctuation (SF), Pattern Standard Deviation (PSD), and Corrected Pattern Standard Deviation. (2) Change in each eye between Visits 1 and 5 in proportionate Mean Sensitivity (pMS) for the central annulus of stimulus locations compared with that for the peripheral annulus thereby determining the influence of stimulus eccentricity on any alteration in sensitivity. (3) Change between Visits 1 and 5 in the number and magnitude of the Pattern Deviation (PD) probability levels associated with any alteration in sensitivity. The MD, SF, and PSD each improved over the 5 examinations (each at P<0.001). The improvement in pMS between Visits 1 and 5 was greater for the peripheral annulus than for the central annulus by approximately twofold for the patients with OAG. Considerable variation was present between patients, within and between groups, in the number of locations exhibiting an improving sensitivity between Visits 1 and 5 by 1 or more PD probability levels. Care should be taken to ensure that, during the initial examinations, apparent field loss with SWAP in patients exhibiting a normal field by SAP is not the result of inexperience in SWAP. Apparently deeper or wider field loss in the initial examinations with SWAP compared with that exhibited by SAP in OAG also may arise from inexperience in SWAP.

Detection of Psychophysical and Structural Injury in Eyes With Glaucomatous Optic Neuropathy and Normal Standard Automated Perimetry

To compare the prevalence of structural and psychophysical abnormalities in normal eyes and eyes with glaucomatous optic neuropathy (GON) and normal standard automated perimetry (SAP). Complete examination, SAP, short-wavelength automated perimetry (SWAP), frequency doubling technology (FDT), scanning laser polarimetry (GDx-VCC), and optical coherence tomography (OCT) of the peripapillary retinal nerve fiber layer (RNFL), optic disc, and macula were performed. Glaucomatous optic neuropathy was defined as cup-disc asymmetry between fellow eyes of greater than 0.2, rim thinning, notching, excavation, or RNFL defect. All eyes had normal SAP. Abnormal measurements on OCT, GDx-VCC, SWAP, and FDT were defined as those outside 95% normal limits. Eyes were stratified into 3 groups based on the OCT-generated vertical cup-disc ratio: mild, moderate, and advanced cupping (cup-disc ratio of <0.4, 0.4-0.7, and >0.7, respectively). Receiver operating characteristic curves were developed to assess sensitivity and specificity of structural and functional assessments. Forty-seven eyes of 47 patients (25 with GON and 22 normal) were enrolled (mean +/- SD age, 58 +/- 16 years; range, 25-83 years). Compared with normal eyes, eyes with GON had significantly worse mean deviation and pattern standard deviation by means of SWAP and FDT (P = .02-.05); OCT-derived mean and superior and inferior RNFL thickness (P = .008, <.001, and .05, respectively); mean macular thickness (P = .01), rim volume, rim area, cup-disc ratio, and cup area (all P<.001); and GDx-VCC nerve fiber indicator and inferior average (P = .03). There was a significantly (P = .008, .002, .003, and .01, respectively) greater prevalence of abnormalities identified by SWAP, FDT, OCT and GDx-VCC in eyes with advanced cupping (43%, 43%, 57%, and 57%, respectively) compared with mild cupping (0%) and moderate cupping (9%, 5%, 19%, and 33%, respectively). Eyes with GON and normal results of SAP have significantly greater structural and psychophysical abnormalities than do normal eyes evaluated by means of OCT, GDx-VCC, SWAP, and FDT. Eyes with increased vertical cup-disc ratio are more likely to manifest such abnormalities on advanced diagnostic testing.

Contrasting Blue-on-Yellow with White-on-White Visual Fields: Roles of Visual Adaptation for Healthy Peri- or Postmenopausal Women Younger Than 70 Years of Age

To test the hypothesis that differences between short-wavelength automated perimetry (SWAP) and white-on-white visual field sensitivities are related to between-individual variation in the visual adaptation properties of SWS cone pathways. Twenty-six healthy amenorrheic (peri- or postmenopausal) women not using hormonal medication were tested. Subjects ranged in age from 48 to 68 years. They were tested by using foveal increment-threshold techniques and also with two types of 24-2 visual field tests: a full-threshold SWAP blue-on-yellow (B/Y) test and a white-on-white (W/W) test obtained using a Swedish Interactive Threshold Algorithm (SITA Standard). The age-corrected sensitivity differences between the two types of visual fields were compared against foveal measures of visual sensitivity and adaptation, which were obtained psychophysically using dim and bright yellow backgrounds. All measurements for each subject were made at a single testing session. The comparisons were made for the entire visual field and for separate portions of the visual field. The analyses also included pupil size data obtained during visual field testing. The B/Y minus W/W (B/Y - W/W) mean deviation difference was described (R = 0.80) by a multilinear model with three significant factors: (1) an adaptation factor and (2) a baseline sensitivity factor, each derived from the foveal psychophysical data for short-wavelength test stimuli, and (3) a pupil size factor, as recorded for SWAP. The total deviation differences in the periphery of the visual field (approximately 22 degrees from fixation) were described (R = 0.87) by a model with four significant factors, the fourth being an "eccentricity factor" describing the rate of change of the B/Y - W/W total deviation difference measured as a function of increasing retinal eccentricity approximately 9 degrees -17 degrees from fixation. More than 40% of the variance in the B/Y - W/W mean deviation differences was accounted for either directly or indirectly (via effects of pupil size) by variations in adaptation to the yellow background used for SWAP. Much of the extra variability in SWAP sensitivities for a select group of healthy women can be accounted for by differences in the degree of desensitization induced by the yellow background used for SWAP. For clinical practice, pupil status (dilated or undilated) should be altered only with caution from one SWAP testing session to another.

Visual fields correlate better than visual acuity to severity of diabetic retinopathy

We compared the outcomes of perimetric and visual acuity tests in patients with diabetic retinopathy. We examined 59 diabetic patients with different degrees of retinopathy using stereo fundus photography in accordance with the Early Treatment of Diabetic Retinopathy Study (ETDRS) and fluorescein angiography. Conventional white-on-white perimetry (WWP) and short wavelength automated perimetry (SWAP) were performed and analysed with reference to normal values. Visual acuity was measured with ETDRS charts. Regression analysis revealed that visual acuity was significantly associated with increasing severity of retinopathy according to the ETDRS scale when visual acuity was estimated by counting logarithm of minimum angle of resolution (LogMar) scores, but not when visual acuity was measured by the conventional reading of the smallest line that could be seen. Visual acuity decreased by 0.02 LogMar per ETDRS step (p=0.03). The degree of visual field loss was significantly associated with increasing severity of retinopathy according to the ETDRS scale, perimetric sensitivity decreasing by 0.44 dB per ETDRS step (p=0.0001) using WWP, and by 0.40 dB per ETDRS step (p=0.04) with SWAP. The size of the area of the foveal avascular zone and adjacent perifoveal intercapillary areas (PIAs) also affected the central visual field as obtained both by WWP (-2.6 dB/mm2, p=0.03), and by SWAP (-7.9 dB/mm2, p=0.002), but did not affect visual acuity. The regression model fit for peripheral retinopathy according to the ETDRS scale was better using WWP than SWAP or visual acuity, while SWAP testing was superior to both WWP and visual acuity when measuring effects caused by enlarged foveal avascular zones and PIAs. Perimetry can provide more useful information than visual acuity on functional loss in diabetic retinopathy, particularly when the perifoveal capillary network is damaged.

Conventional Perimetry, Short-Wavelength Automated Perimetry, Frequency-Doubling Technology, and Visual Evoked Potentials in the Assessment of Patients with Multiple Sclerosis

To evaluate the diagnostic power of conventional, achromatic, automated perimetry (CAP), short-wavelength automated perimetry (SWAP), frequency-doubling technology (FDT) perimetry, and visual evoked potentials (VEP) in a group of patients with multiple sclerosis (MS) with or without a history of optic neuritis. Thirty eyes of 15 patients (5 male, 10 female, average age 38+/-7 years) with confirmed diagnosis of MS underwent CAP, SWAP (Humphrey 750-II VFA, program central 30-2, full-threshold strategy), FDT perimetry (program N-30), and pattern VEPs. Sixteen eyes (53.3%) had no history of ocular involvement and a negative ophthalmologic examination. They were matched with a control group of 10 healthy volunteers (4 male, 6 female, average age 31+/-10 years). The mean deviation (MD) and the pattern standard deviation (PSD) of the two groups were compared (t-test). Fourteen eyes (46.7%) had, on the contrary, a history of optic neuritis. Inside this group, the MD and the PSD of the three techniques were correlated (Spearman's rank test), in order to investigate whether any significant differences might be revealed by these techniques in pointing out the total amount of visual field damage. When comparing MS patients without signs or symptoms of ocular involvement and a control group, no significant differences were found for CAP MD, CAP PSD, and FDT PSD. Significant differences were found, on the contrary, for SWAP MD (p=0.0014), SWAP PSD (p=0.0001), and FDT MD (p=0.0001). When considering the MD and the PSD of the three techniques in the group of MS patients who had a history of optic neuritis, a significant correlation was found only between CAP MD and SWAP MD (r=0.0057), with a tendency by SWAP to reveal a higher rate of visual field loss. The other correlations were not significant. According to predefined criteria, the group of asymptomatic subjects had abnormal CAP in 1 eye (6.25%), abnormal SWAP in 9 (56.2%), abnormal FDT in 11 (68.7%), and abnormal VEPs in 7 (43.7%). The combined use of all techniques allowed us to identify silent optic nerve impairment in 15 (93.7%) eyes. Short-wavelength automated perimetry and FDT perimetry are two non-conventional perimetric techniques that were mainly developed for the early detection of glaucomatous damage. The results of this study demonstrate their efficacy also in detecting early visual field deficits in MS patients without clinical signs of optic neuropathy. Frequency doubling perimetry, in particular, proved to be an easy, fast, and sensitive technique in the assessment of patients with MS. Our results also suggest that subclinical visual involvement in MS can be better diagnosed using multiple (neurophysiologic and psychophysical) tests.

Ocular Hypertension and Corneal Thickness: A Long-Term Prospective Study. Results after Two Years

To study the importance of the central corneal thickness (CCT) in patients with ocular hypertension in a 2-year follow-up. A total of 110 subjects with ocular hypertension (intraocular pressure [IOP] >21 mmHg and normal automated visual field test) were admitted to the study. All patients periodically underwent the following tests: 1) circadian IOP curve; 2) standard automated perimetry (SAP, Humphrey 30-2 SITA test); 3) short wavelength automated perimetry (SWAP); 4) frequency doubling technology perimetry (FDT, N-30 threshold test); 5) nerve fiber layer analysis with GDx; 6) ibopamine test; 7) ultrasonic pachymetry. Patients were divided into three groups, based on corneal thickness. The frequency of abnormal tests within these groups was evaluated with the Pearson's chi2 test. Baseline IOP was corrected using the Doughty and Zaman formula. CCT was also considered as a continuous variable. A control group of 48 normal subjects was also considered. The mean CCT was 562.8 microm +/- 37.7. The difference with respect to normal subjects was statistically significant (p < 0.01). Using the correction formula, 43 eyes (39.1%) had an IOP <21 mmHg. Abnormal test results were more frequently found with FDT. The percentage of abnormal results was found to be inversely proportional to CCT. The other tests gave inconsistent or conflicting results. Using the values of CCT as a continuous variable, no significant association was found with the GDx number and the visual field indices. The results of our 2-year study confirm the importance of CCT measurement in the evaluation of the risk of developing glaucomatous damage.

Topical dorzolamide increases pericentral visual function in age‐related maculopathy: pilot study findings with short‐wavelength automated perimetry

Numerous studies have confirmed the enhancement of ocular circulation by carbonic anhydrase inhibitors (CAIs). Topical CAI treatment with dorzolamide averts the significant pericentral visual function loss accompanying retinal and choroidal vasoconstriction during acute hyperventilation-induced hypocapnia. This study was designed to discern whether dorzolamide might similarly enhance macular function in patients with age-related maculopathy (ARM). In a masked, placebo-controlled study, 40 patients with ARM and acuity > 20/50 were randomized to receive either dorzolamide or placebo for 12 weeks, thrice daily. After pre-study perimetric training, pericentral function (mean sensitivity) was quantified using Humphrey 10-2 short-wavelength automated perimetry (SWAP), before and after 12 weeks of topical therapy. Dorzolamide-treated eyes demonstrated a significant increase in mean sensitivity of + 1.55 dB (p = 0.04); placebo-treated eyes showed no significant change (+ 0.58 dB; p = 0.10). Given the non-significant increase of mean sensitivity in the placebo-treated group, fewer than 100 subjects per group would be required to afford > 70% power to yield a significant direct comparative difference between treatment and placebo in a prospective, randomized study of equally short duration. This study demonstrated a significant increase in short-wavelength sensitivity in ARM with dorzolamide and the lack thereof with placebo. These encouraging pilot study data suggest a potential role for topical CAIs in ARM patients, and establish objective parameters for prospective studies to further evaluate the effects of dorzolamide in ARM.

Effect of the menstrual cycle on standard achromatic and blue-on-yellow visual field analysis of women with migraine

Background: It has been postulated that migraine and glaucoma may have common vascular causative factors. Significant sex-based differences in the incidence of many important ocular conditions raise the possibility that estrogens may have direct effects on the eye.We performed a study to determine the effect of the menstrual cycle on standard achromatic automated perimetry (SAP) and short-wavelength automated perimetry (SWAP) (blue-on-yellow perimetry) of women with migraine.Methods: Both eyes of 73 normally menstruating women (31 subjects with migraine and 42 healthy control subjects) were included in the study. Subjects underwent a complete ocular examination including SAP and SWAP in both the follicular phase (12th to 13th day of the cycle) and the luteal phase (1 to 2 days before the onset of bleeding) of two consecutive menstrual cycles.We performed visual field analysis using the Humphrey Field Analyzer II with the full-threshold central 30-2 program. Mean sensitivity was calculated for the superior temporal, inferior temporal, superior nasal and inferior nasal regions separately.Results: Thirteen subjects were lost to follow-up (5 in the migraine group and 8 in the control group), leaving 26 subjects and 34 subjects respectively.There was no significant difference in mean age between the two groups (33.9 years [standard deviation (SD) 3.4 years] vs. 35.1 years [SD 3.3 years]). The mean duration of migraine was 7.6 (SD 3.1) years (range 3-14 years). In both groups, serum estradiol levels were significantly lower (p = 0.001) and serum progesterone levels were significantly higher (p < 0.001) in the luteal phase than in the follicular phase. In the control group, the mean sensitivity values with SWAP were significantly lower in the luteal phase than in the follicular phase (p = 0.04). A similar decrease was observed for the subjects with migraine with both SAP and SWAP (p = 0.01).There was no difference in regional mean sensitivity between the two phases with either perimetric test in the control group. For the subjects with migraine, there was no difference in regional mean sensitivity between the two phases with SAP. However, with SWAP, the mean sensitivity for the nasal visual field locations was significantly lower in the luteal phase than in the follicular phase (p = 0.01).Interpretation: Our study provides further evidence of an effect of sex hormones on the visual field of women with migraine. In addition to assessment of intraocular pressure, menstrual cycle phases should be considered in women with migraine at risk for glaucomatous optic neuropathy.