Frequency Doubling Technology Perimetry Research Articles

MODERN METHODS FOR DIAGNOSTICS OF GLAUCOMA

Glaucoma is a chronic optical neuropathy characterized by loss of ganglion cells with the development of specific changes in the optic nerve head (ONH) and retinal nerve fiber layer (RNFL). Early detection of the disease plays an important role in preventing the development structural abnormalities and irreversible vision loss. Diagnosis of glaucoma is based on assessing the safety of optic nerve structures and visual functions results clinical examination of the optic disc and RNFL are subjective and vary greatly. In connection with this, research in recent years has been aimed at developing additional objective methods for diagnosing glaucoma. The possibility of using confocal scanning laser ophthalmoscopy, scanning laser perimetry and optical coherence tomography to assess the condition of the optic disc. In order to ensure early detection of visual field defects options are currently being considered replacing standard automated perimetry (SAP) with selective, which includes short-wavelength automated perimetry (SWAP) and perimetry with the illusion of spatial doubling frequencies (frequency-doubling technology perimetry, FDT). The article is an overview modern method for diagnosing glaucoma in the context of their use in clinical practice.

New possibilities of perimetry in screening and early diagnosis of glaucoma

PURPOSE. To study the diagnostic effectiveness of an improved software version of the well-known authors' modification of Frequency Doubling Technology (FDT) perimetry by comparing it with the previous software version and standard automated perimetry on the same contingent of healthy individuals and patients with primary open-angle glaucoma (POAG).METHODS. The study included 56 patients (105 eyes) (mean age 61±13.2 years) with POAG. Patients were divided into three groups depending on the stage of glaucoma: group 1 — early stage (39 eyes), group 2 — moderate (25 eyes), and group 3 — advanced (9 eyes) stage. The fourth (control) group included 32 eyes of 16 healthy people (average age 48.2±6.2 years). All study subjects underwent standard automated perimetry (SAP) on the Humphrey III visual field analyzer and non-standard perimetry in the form of our own modification of FDT perimetry and its improved software version — FDT VR version based on the new portable automatic perimeter "Stimulus" (OOO Total Vizhen, Russia). The optic nerve disc was evaluated on the Heidelberg Retina Tomograph 3.RESULTS. The software version of the authors' modification of FDT perimetry has been improved for liquid crystal monitors and adapted to the portable perimeter "Stimulus". When comparing diagnostic effectiveness, both variants of FDT perimetry are not inferior to SAP in sensitivity (87.6; 87.8 and 86.7%, respectively), and in terms of specificity (98.2; 98.1 and 84.4%, respectively) they are superior. A strong (r=0.99988) and reliable (p<0.05) correlation was found between the average values of light sensitivity for both variants of FDT perimetry.CONCLUSION. The introduction of FDT perimetry based on the new portable automatic perimeter "Stimulus" into widespread ophthalmological practice can contribute to improving the effectiveness of screening and early diagnosis of glaucoma.

Prevalence and Cause of Loss of Visual Acuity and Visual Field in Highly Myopic Eyes: The Beijing Eye Study

To explore prevalence and causes of loss of visual acuity and visual field in highly myopic eyes. Population-based study. The participants (n=4439) of the Beijing Eye Study underwent an ophthalmological and systemic examination including frequency doubling technology perimetry (FDT). High myopia was defined by a refractive error of ≤-6Dpt or axial length >26.0 mm. Prevalence of vision impairment causes. The study included 212 highly myopic eyes (154 participants;mean age:56.2±9.6 years;refractive error:-9.87±3.70 Dpt;range:-20.87 to -6.00Dpt; axial length:27.2±1.3mm;range:26.01-30.88mm). Moderate/severe vision impairment (MSVI) (best corrected visual acuity (BCVA) from <6/18 to 3/60) and blindness (BCVA <3/60 or <10° visual field around central fixation) was present in 40/212 (18.9%;95%CI:13.6,24.2) eyes, and in 10/212 (4.7%;95%CI:1.8, 7.6) eyes, respectively. BCVA decreased with more myopic refractive error (beta:-0.55;B:-0.08;95%CI:-0.09,-0.06;P<0.001). Primary (i.e., most influential) causes for MSVI and blindness were myopic macular degeneration (MMD) (29/50;58%), age-related macular degeneration (1/50;2%), and branch macular retinal vein occlusion (1/50;2%). Secondary causes were MMD (4/50;8%) and optic nerve atrophy (14/50 (28%), differentiated into a non-glaucomatous type (NGOA) (9/50;18%) and glaucomatous type (GOA) (5/50;10%). Prevalence of MMD as vision impairment cause (mean:40/212 (18.9%;95%CI:13.6,24.2) increased from 1/61 (1.6%;95%CI:0.00,4.9) in the group of -6.00 to ≥-7.00Dpt, to 16/25 (64.0%;95%CI:43.8,84.2) in the group of <-15.0Dpt. Higher MMD prevalence correlated with higher myopic refractive error (OR:0.70;95%CI:0.61;0.81;P<0.001) and higher prevalence of concomitant optic neuropathy (OR:86.2;95%CI:16.1,463;P<0.001). Optic neuropathy prevalence as cause of vision impairment (mean:19/212;9.0%;95%CI:5.0,13.0) increased from 0/61 (0%) in the refractive error group of -6.00Dpt to ≥-7.00Dpt, to 9/25 (36.0%;95%CI:16.0,56.0) in the group of <-15.0Dpt. Higher optic neuropathy prevalence correlated with more myopic refractive error (P<0.001) and older age (P=0.02). GOA prevalence (mean:6/212;2.8%;95%CI:1.0,5.0) and NGOA prevalence (mean:13/212 (6.1%;95%CI:3.0,9.0) increased from 0/61 (0%) in the group of -6.00 to ≥-7.00Dpt, to 4/25 (16.0%;95%CI:1.0,31.0) and 5/25 (20%;95%CI:3.0,37.0), respectively, in the group of <-15.0Dpt. In this population-based recruited, highly myopic cohort, prevalence of optic neuropathy (9.0%) as vision impairment cause was lower than MMD prevalence (18.9%), and it was an important reason for vision impairment in the group of <-15Dpt. MMD was vision impairment cause in 16/25 (64.0%) eyes with <-15.0Dpt refractive error.

Assessment of the Effectiveness of Different Variants of Frequency Doubling Technology Perimetry in Monitoring the Glaucoma Process

Purpose: To compare the diagnostic effectiveness of non-standard perimetry and standard automated perimetry (SAP) during earlystage monitoring of primary open-angle glaucoma (POAG).Patients and methods. The study involved 30 patients (46 eyes) with early-stage of POAG, aged 30 to 65 years (54.9 ± 1.3), who were under ongoing monitoring for 3 to 4 years (3.50 ± 0.68 years). All subjects, in addition to the standard ophthalmological examination, performed the threshold program “24-2” perimetry using the Humphrey II, the own modification of Frequency Doubling Technology (FDT) Perimetry, in the form of 2 threshold strategies: the wellknown “FDT-16” and the new “FDT-64”. The condition of the optic nerve head (ONH) was assessed using HRT 3 (Heidelberg Retina Tomograph, Germany) and OCT — Topcon 3D OCT- 2000 (TOPCON, Japan). During monitoring, RTVue FD-OCT (Optovue, USA) was additionally performed, evaluating the parameters of the retinal ganglion cell complex (GCC).Results. Regular follow-up, the implementation of the prescribed treatment contributed to the stabilization of glaucoma, as evidenced by the stability of the average MD index values according to all 3 threshold strategies, but reliably (p = 0.000) only according to SAP data. According to the criterion of the number of scotomas, there was a weakly expressed, but statistically significant negative dynamics for all the compared strategies. According to the results of the structural assessment of the ONH (the size of the excavation), a weakly pronounced negative dynamics was obtained in dynamics according to both HRT and OCT data. The average MD index values, the number of scotomas according to the three perimeter strategies and the excavation size based on HRT and OCT in patients with early-stage of POAG turned out to be stronger and more significant using the “FDT-16”, and the correlation characteristics with the results of “24-2” HFA II, “FDT-64” largely coincided.Conclusion. A reliable correlation between structural and functional parameters indicates the feasibility of using “FDT-64” in combination with SAP not only in for the diagnosis of the early-stage of glaucoma, but also in assessing its course. The sensitivity level of the results of “FDT-64” (100 %) compared to “FDT-16” (88 %) in patients with POAG was higher, therefore, “FDT-64” is advisable to use in complex diagnostic cases and in monitoring glaucoma.

Diagnostic Accuracy of Frequency-Doubling Technology and the Moorfields Motion Displacement Test for Glaucoma

Portable perimetric testing could be useful for community-based glaucoma screening programs. Frequency-doubling technology (FDT) and the Moorfields motion displacement test (MDT) are portable perimeters that have shown promise as potential screening tools for glaucoma. This study's goal was to determine the diagnostic accuracy of FDT and MDT for visual field defects and glaucoma. Prospective, cross-sectional, diagnostic accuracy study. A consecutive series of patients aged ≥ 50 years who presented to a glaucoma clinic in South India and had never undergone Humphrey field analyzer (HFA) visual field testing in the past. Participants underwent 24-2 Swedish Interactive Thresholding Algorithm (SITA)Standard HFA perimetry, FDT perimetry, MDT perimetry, and iPad perimetry using visualFields Easy in random order. Ophthalmologist grades of HFA and optic nerve head photographs were used as reference standards for glaucoma and field defect presence. Receiver operating characteristic curves were constructed to assess the diagnostic accuracy of various parameters for each test. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). Overall, 292 eyes from 173 participants were included, with 112 eyes classified as moderate or worse glaucoma. For moderate or worse glaucoma detection, the best parameter on FDT was mean deviation (MD) (AUROC, 0.84; 95% confidence interval [CI], 0.79-0.89) and the best parameter on MDT was global probability of true damage (GPTD) (AUROC, 0.87; 95% CI, 0.82-0.91). When specificity was set to 90%, the sensitivity for detection of moderate or worse glaucoma was 55% (95% CI, 39%-68%) for FDT MD and 62% (95% CI 52%-71%) for MDT GPTD. Frequency-doubling technology and MDT perimetry had fair diagnostic accuracy for glaucoma detection when administered to naïve test takers in this South Indian population. Although not appropriate for use as a sole glaucoma screening test, these perimetric tests may be useful as ancillary tests. Proprietary or commercial disclosure may be found after the references.

Comparison between frequency-doubling technology perimetry and standard automated perimetry in early glaucoma

This study aimed to find out the significance of the difference between frequency-doubling technology perimetry (FDT) and standard automated perimetry (SAP) in terms of the detected visual field (VF) damage, and evaluate associated factors to SAP–FDT difference in early glaucoma. Glaucoma patients in early stage (MD better than − 6.0 decibel, 96 eyes) were included in this cross-sectional study. We subtracted mean deviation (MD) and pattern standard deviation (PSD) of FDT from those of SAP, respectively. Additionally, we counted significantly depressed points of P < 5% and P < 1% on the pattern deviation probability plot of both FDT and SAP and defined eyes with significant SAP–FDT difference when the number of abnormal points were greater than 4 points on FDT. We measured lamina cribrosa depth (LCD) and lamina cribrosa curvature index (LCCI) for structural parameters of the optic nerve head from images using enhanced depth imaging of the optical coherence tomography (OCT). Peripapillary vessel density (VD) and presence of microvasculature dropout (MvD), the complete loss of choriocapillaris in localized regions of parapapillary atrophy, was evaluated using deep layer map of OCT angiography (OCT-A) for vascular parameters. Peripheral nasal step (PNS) group had an isolated glaucomatous VF defect within nasal periphery outside 10° of fixation. Parafoveal scotoma (PFS) group had an isolated glaucomatous VF defect within 12 points of a central 10˚ radius. Eyes with significant SAP–FDT difference showed higher detection of MvD on deep layer map of OCT-A, greater LCD, and greater LCCI (all P < 0.05, respectively). In logistic regression analysis, frequent presence of MvD, less presence of disc hemorrhage, and greater LCD were significantly associated with significant SAP–FDT difference. Sub-analysis was performed in eyes with PNS (50 eyes) and PFS (46 eyes). SAP–FDT difference of MD value showed positive association with peripapillary VD on deep layer of OCT-A, which was significant in eyes with PFS compared to eyes with PNS. SAP–FDT difference of PSD value showed negative association with LCCI and LCD, which was significant in eyes with PNS compared to eyes with PFS. Glaucomatous eyes classified by the difference of the detected VF damage on FDT versus SAP showed different clinical features. Greater SAP–FDT difference was significantly associated with structural parameters such as LCD and LCCI. Less SAP–FDT difference was associated with presence of disc hemorrhage and lower deep layer peripepillary VD. There is possibility to use the difference of SAP and FDT to identify associated risk factors in glaucoma patients.

Multiple Sclerosis: What Methods are Available for the Assessment of Subclinical Visual System Damage?

ABSTRACT We aimed to assess the visual fields and optical coherence tomography (OCT) measurements in patients with multiple sclerosis (MS) to detect subclinical visual system disease. The study included 15 MS patients with previous optic neuritis (Group I), 17 MS patients without previous optic neuritis (Group II), and 14 healthy controls (Group III). Each subject underwent standard automated perimetry (SAP), frequency doubling technology perimetry (FDTP), and OCT. The mean deviation of SAP in Group I was lower than those in Groups II (p = .018) and III (p = .001). The pattern standard deviation of SAP in Group I was higher than those in Group III (p < .0001). The mean deviation of FDTP in Groups I and II was lower than those in Group III (p = .0001 and p = .016, respectively). The temporal quadrant of the retinal nerve fibre layer in Group I was thinner than those in Groups II and III (p = .005 and p = .003, respectively). The mean macular volume in Group I was thinner than those in Groups II and III (p = .004 and p = .002, respectively). A single method is inadequate for establishing early and/or mild visual impairment in MS. All conventional and non-conventional techniques are complementary in demonstrating subclinical visual damage in MS.

Evaluation of the effectiveness of frequency doubling technology perimetry in the diagnosis of optic neuropathies

PURPOSE. To compare the diagnostic effectiveness of two perimetric threshold strategies with frequency-doubling technology in patients with early primary open-angle glaucoma (POAG), the optical form of multiple sclerosis (MS) and papilledema in an open-label comparative clinical study.MATERIAL AND METHODS. The study involved 78 patients (105 eyes) with optic neuropathies (ON). The patients were divided into 3 groups depending on the etiology of optic neuropathy: the first group included 30 patients (46 eyes) with early POAG aged 30 to 65 years (54.9±1.3); the second group included 26 patients (26 eyes) diagnosed with the optic form of MS (an episode of retrobulbar optic neuritis in the medical history) aged 22 to 44 years (33.7±6.5); the third group consisted of 22 patients (33 eyes) aged from 18 to 66 years (35.7±14.9) with papilledema caused in the majority of cases by various brain tumors (25 eyes or 75.7%). The fourth (control) group consisted of 60 healthy individuals (60 eyes) aged 20 to 65 years, who were divided into 2 equal subgroups – younger (24.8±4.4) and older (56.4±3.9).Standard and non-standard perimetry was performed on all subjects during a comprehensive ophthalmic examination using the Humphrey 745i Visual Field Analyzer II (HFA II, «24-2» threshold strategy) (Germany-USA) and the author's own modification of Frequency Doubling Technology (FDT) Perimetry, in the form of 2 threshold strategies: the well-known «FDT-16» and the new «FDT-64».RESULTS. Both the «FDT-16» and the «FDT-64» threshold strategies were more effective in diagnosing glaucomatous optic neuropathy (GON), as confirmed by the higher sensitivity of their results to two criteria — the number of identified scotomas (n of scotomas n≥2), and the number of scotoma clusters in patients with POAG (88 and 100%; 95 and 83%, respectively) compared with those in patients with MS (61 and 76%; 85 and 54%, respectively) and papilledema (51 and 78%; 88 and 70%, respectively). The specificity of the «FDT-16» and «FDT-64» threshold strategies was significantly higher than the specificity of Humphrey perimetry (100, 80 and 63%, respectively).CONCLUSION. Both perimetric threshold strategies with frequency-doubling technology were found to be the most effective in detecting GON. This confirms that they are more sensitive in patients with early POAG when compared with the sensitivity in patients with MS and papilledema. The level of specificity of both FDT perimetry strategies far exceeds the level of specificity of Humphrey perimetry data, which indicates the advantage of FDT perimetry in separating healthy people from patients with ON, and not only of glaucoma genesis.

New options for the diagnosis of normal tension glaucoma in the light of Professor V.V. Volkov’s concept of its pathogenesis

PURPOSE:To measure lamina cribrosa thickness (LCT) and lamina cribrosa depth (LCD), optic nerve subarachnoid space width (ONSASW) in patients with normal tension glaucoma and in healthy individuals and to compare these data with the results of our own pilot study.&#x0D; MATERIALS AND METHODS:The 1st group included 13 patients (22 eyes) with normal tension glaucoma aged 39 to 88 years (59.8 10.9 years). The 2nd (control) group included 10 healthy people (20 eyes) aged 40 to 59 years (47.9 5.5 years). All subjects underwent structural and functional assessment of the optic nerve head using optical coherent tomograph (OCT) RTVue-100 (Optovue, USA), Humphrey perimeter (HFA II 745i, Germany-USA), and our own modification of Frequency Doubling Technology perimetry. LCT and LCD were measured by OCT RS-3000 Advance (Nidek, Japan). To measure ONSASW we used a cross-sectional image of the optic nerve taken with Magnetic Resonance Imaging (GE Optima MR450w MRI, USA).&#x0D; RESULTS:Differences in the 1st and 2nd groups between the mean values of LCT (234.14 27.73 and 336.25 21.0 m, respectively;p= 0.0000), LCD (461.8 101.7 and 361.65 58.2 m, respectively;p= 0.0004) and ONSASW (1.371 0.035 and 1.52 0.133 mm, respectively;p= 0.011) were statistically significant.&#x0D; CONCLUSION:Patients with normal tension glaucoma had significantly higher LCD value with significantly lower LCT and ONSASW values compared to healthy individuals, which is comparable with the results of our pilot study, and confirms the importance of these morphometric criteria in normal tension glaucoma diagnosis verification.

Bruch Membrane Opening Minimum Rim Width in Neuromyelitis Optica.

Optical coherence tomography (OCT) analyzes the neurodegeneration in neuromyelitis optica (NMO) and multiple sclerosis (MS) and quantifies optical atrophy. The retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness are decreased, and this structural change is correlated with visual function of patients, including contrast vision and visual field deviation. The main objective of this study was to evaluate the Bruch membrane opening minimum rim width (BMO) of the patients with NMO. We studied the thickness of the BMO by OCT, in patients with NMO (n = 25; 34 eyes), MS (n = 50; 70 eyes), and a control group (n = 51; 100 eyes). The study evaluated the structure-function relationship with the correlation between OCT and visual function: Visual acuity, Pelli-Robson score, Sloan 2.5 and 1.25, color vision, standard automated perimetry (SAP), and frequency-doubling technology perimetry (FDT). The average thickness of BMO was significantly reduced in NMO and MS with or without a history of optic neuritis (ON). Significant thinning of the average, nasal, and inferonasal BMO in the absence of ON in NMO was found compared with controls (P = 0.022, 0.006, and 0.026, respectively). BMO was strongly correlated with Pelli-Robson score (P < 0.001), Sloan 2.5 (P < 0.001), and mean deviation of SAP and FDT (P = 0.004). The sectorial study found a high correlation between the BMO and the corresponding sector of the visual field. The BMO thickness is decreased after ON in NMO and MS. This study showed an improved ability of BMO over RNFL and GCL to detect infraclinical impairment in patients with NMO without a history of optic neuropathy. Like the RNFL and GCL, BMO is well correlated with visual function, including contrast vision and visual field deviation.

Non-standard computer perimetry in the diagnosis of some optic neuropathies

Modern computer perimetry is divided into traditional white stimulus-on-white background, the gold standard of which is perimetry performed by using expert class perimeters Humphrey and Octopus and therefore called standard automatic or automated perimetry (SAP), and non-traditional or non-standard perimetry, which differs, first of all, in a different nature of a stimulus. The article is a review devoted to the assessment of the diagnostic capabilities of non-standard computer perimetry in the form of different variants of perimetry with doubling the spatial frequency (Frequency Doubling Technology Perimetry or FDT perimetry), which is performed by using perimeters of the 1st (Carl Zeiss Humphrey 710 Visual Field / FDT, 1997) and the 2nd (Carl Zeiss Humphrey Matrix / HM 715, 800 Visual Field Analyzer, 2005, 2010) generation. Most authors consider that FDT perimetry is effective in a glaucoma screening and, possibly, in monitoring a glaucomatous process, but only a few authors consider that non-standard perimetry method can be useful in diagnosing optic neuropathies of a different nature.

Evidence for Structural and Functional Damage of the Inner Retina in Diabetes With No Diabetic Retinopathy.

PurposeTo provide structural and functional evidence of inner retinal loss in diabetes prior to vascular changes and interpret the structure-function relationship in the context of an established neural model.MethodsData from one eye of 505 participants (134 with diabetes and no clinically evident vascular alterations of the retina) were included in this analysis. The data were collected as part of a large population-based study. Functional tests included best-corrected visual acuity, Pelli-Robson contrast sensitivity, mesopic microperimetry, and frequency doubling technology perimetry (FDT). Macular optical coherence tomography volume scans were collected for all participants. To interpret the structure-function relationship in the context of a neural model, ganglion cell layer (GCL) thickness was converted to local ganglion cell (GC) counts.ResultsThe GCL and inner plexiform layer were significantly thinner in participants with diabetes (P < 0.05), with no significant differences in the macular retinal nerve fiber layer or the outer retina. All functional tests except microperimetry showed a significant loss in diabetic patients (P < 0.05). Both FDT and microperimetry showed a significant relationship with the GC count (P < 0.05), consistent with predictions from a neural model for partial summation conditions. However, the FDT captured additional significant damage (P = 0.03) unexplained by the structural loss.ConclusionsFunctional and structural measurements support early neuronal loss in diabetes. The structure-function relationship follows the predictions from an established neural model. Functional tests could be improved to operate in total summation conditions in the macula, becoming more sensitive to early loss.

Magnocellular visual function in developmental dyslexia: deficit in frequency-doubling perimetry and ocular motor skills.

This study aimed to verify if patients with developmental dyslexia present deficits coherent with visual magnocellular dysfunction. Participants with confirmed diagnosis of developmental dyslexia (n=62; age range=8-25 years; mean age=13.8 years, standard deviation=3.9; 77% male) were compared to a control group with normal development, matched for age, sex, ocular dominance, visual acuity, and text comprehension. The frequency-doubling technology perimetry was used to evaluate the peripheral visual field contrast sensitivity threshold. The Visagraph III Eye-Movement Recording System was used to evaluate ocular motor skills during text reading. The developmental dyslexia group had significantly worse contrast sensitivity in the frequency-doubling technology, with strong effect size, than the matched control group. The developmental dyslexia group had more eyes classified in the impaired range of sensitivity threshold to detect frequency-doubling illusion than the control group. Moreover, the developmental dyslexia group had poorer ocular motor skills and reading performance, revealed by a difference in ocular fixations, regressions, span recognition, reading rate, and relative efficiency between groups. A significant correlation was found between contrast sensitivity and ocular motor skills. Participants with good relative efficiency had significantly better contrast sensitivity than participants with poor relative efficiency. The developmental dyslexia group presented a markedly worse performance in visual variables related to visual magnocellular function (i.e., frequency-doubling technology perimetry and ocular motor skills) compared with a matched control group. Professionals need to be aware of the importance of evaluating vision of individuals with developmental dyslexia beyond visual acuity and including in their assessments instruments to evaluate temporal processing, with contrast sensitivity threshold.

Correlation of Vertical Cup Disc Ratio and Matrix FDT Mean Deviation in Primary Open Angle Glaucoma Patients

Objectives: To evaluate the correlation between glaucomatous structural change using vertical-cup-disc ratio of the optic nerve head and functional loss measured by Frequency Doubling Technology perimetry. Materials and methods: It was a retrospective observational clinic-based study of 77 newly diagnosed Primary Open Angle Glaucoma (POAG) patients from a Private Eye clinic in a suburb of Port Harcourt city, Nigeria. They underwent clinical fundal examination with slit-lamp biomicroscope (Perkin’s slit-lamp) with 90D (Volk) lens; and Frequency Doubling Technology perimetry 24-2 threshold (Humphrey Matrix 800, 2011 Carl Zeiss Meditec, Dublin, California). The Vertical-cup-disc-ratio was assessed for each eye and the Mean deviation calculated for each eye. The relationship between VCDR and mean deviation was evaluated using Pearson’s correlation coefficient regression analysis. Result: There were 24 males (31.17%) and 53 females (68.83%). The mean age of the patients was 56.65 ± 14.33 years with a range of 37-78 years. The mean VCDR was 0.83±0.09 and 0.78±0.13 for the right and left eyes, respectively while mean FDT mean deviation was -13.99±9.33Db and -11.9.22Db for the right and left eyes, respectively. The VCDR significantly correlated with FDT mean deviation (Pearson Correlation Coefficient, r= -0.923, r2= 0.852, p-value=0.001 for the right eye; r= -0.915, r2=0.836, p-value=0.001 for the left eye. Conclusion: This study shows that at least 80% of VCDR correlated with the Mean deviation of matrix FDT amongst this cohort of POAG patients. it buttresses the fact that clinical evaluation of the optic nerve remains an indispensable tool in glaucoma diagnosis and can use to assess glaucoma severity in resource poor setting where visual field machine is not available.

Neurofibromatosis Type 1: Ocular Electrophysiological and Perimetric Anomalies.

IntroductionNeurofibromatosis type 1 (NF1) is a multisystemic disease caused by the mutation of Nf1 gene located on chromosome 17q11.2. The mutation determines the loss of function of the protein neurofibromin with consequent uncontrolled cellular proliferation. Patients are characterized by a wide range of dermatological, neurological, and ophthalmological symptoms.PurposeThe aim of the study was to evaluate, through pattern visual evoked potentials (p-VEPs) and frequency doubling technology (FDT) Matrix perimetry, the objective and psychophysical functionality of the optic pathways in a group of NF1 patient.MethodsThe study group consisted of 26 patients affected by NF1 and 17 healthy controls. Each patient underwent a complete ophthalmological examination, p-VEPs with the evaluation of amplitude and latency of the P100 wave, and FDT perimetry, with the evaluation of central sensitivity (CS), mean deviation (MD), pattern standard deviation (PSD) and glaucoma hemifield test (GHT).ResultsNF1 patients showed a statistically significant alteration in the transmission of visual impulse. P-VEPs results highlighted a reduced amplitude and an increased latency of the P100 wave, suggesting an involvement of the visual pathway. Visual field analysis showed a significant reduction in all the observed parameters as well (CS, MD, PSD, and GHT).ConclusionThe present study showed, in NF1 patients, a qualitative and quantitative alteration in the conduction of stimuli through the visual pathways. The observed alterations are present, although, only at a subclinical level. None of the patients included in the study showed any manifest visual deficit nor had any concomitant pathology that might have affected the outcome of the study. In conclusion, electrophysiological exams and computer perimetry may take part, alongside a wider array of exams, in the differential diagnosis and later monitoring of NF1.

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...

Evaluation of the New Compression-Perimeter Test Effectiveness in the Early Diagnosis of Glaucoma

Purpose: To evaluate the effectiveness of a new modification of the vacuum-perimeter test (VPT) by V.V. Volkov in the early diagnosis of glaucoma in comparison with the results of the original test and its known modification — vacuum-compression automated test (VCAT) in an open comparative clinical research. Patients and Methods. The study involved 26 patients (47 eyes) (average age 52.9 ± 8.5 years) with suspected open-angle glaucoma (OAG). Patients were divided into three groups: 1-st — 19 eyes with preglaucoma, 2-nd — 18 eyes with the early stage of OAG, 3-rd — 10 eyes of five patients with unconfirmed glaucoma. The control group (4-th) included 20 eyes of 10 healthy people (average age 56.4 ± 4.4 years). Along with the standard ophthalmological examination, all patients underwent perimetry on Humphrey Visual Field Analyzer II 745i (Germany-USA), our modification of Frequency Doubling Technology (FDT) perimetry, evaluation of the optic nerve head (ONH) on Heidelberg Retina Tomograph (HRT 3, Germany) and three stress tests: VPT, VCAT and our modification — vacuum-contrast-frequency test (VCFT). VCFT was created on the base of FDT perimetry with the aim of increasing the sensitivity of the original test (VPT) for detection of preglaucoma through the use of non-standard stimulus and increasing the number of investigated points of central visual field. Results. According to the National classification (1975) the diagnosis of preglaucoma was determined on the basis of a positive result of at least one of three stress tests, taking into account the risk factors for the development of glaucoma in patients. The early stage of OAG was established on the base of International standards for structural and functional assessment of the ONH (2003). The specificity of all three compared stress tests was 100 %, which confirmed their negative results in all patients (10 eyes) from the 3-rd group. However, the sensitivity of VCFT (75 %) was significantly higher than VPT (21.05 %) and VCAT (21.05 %), which is due, we believe, to the specific nature of VCFT stimulus. Conclusion. According to the obtained data, the developed new modification of VPT — VCFT on the specificity of the results was not worse, and the sensitivity was better than the original VPT and VCAT in the diagnosis of preglaucoma. VCFT is quickly performed and comfortable for patients.

Diagnostic Possibilities of Standard Automatic and FunctionSpecific Perimetry (HFA, Octopus) in the Study of the Visual Field in Patients with Compression in the Chiasm-Sellar Region

The literature review presents the results of a static perimetry for the study of the visual field in patients with compression in the chiasm-sellar region on the Humphrey Visual Field Analyzer (HFA) and Octopus. These models of perimeters are recognized as the “gold standard” and are most widely used in the global ophthalmic practice. The analysis of research results using traditional and function-specific perimetry with selective stimulation of the magnocellular and koniocellular (frequency-doubling technology perimetry, FDT; short-wavelength automated perimetry, SWAP) visual pathways was performed. The literature data analysis allows us to conclude that the static perimetry for the study of the visual field in patients with chiasmatic compression is carried out quite widely and is informative. But despite this, there are no generally accepted recommendations on the use of certain testing strategies and programs for the diagnosis and further dynamic observation of changes in the visual field in patients with this pathology. In this regard, it is advisable to conduct further studies that will allow the formation of standard perimetric protocols for diagnosing and monitoring visual field defects in patients with compression in the chiasm-sellar region based on a comparative analysis of the diagnostic informativity of various strategies and programs.

FDT Perimetry for Glaucoma Detection in Comprehensive Health Checkup Service.

We aimed to investigate the efficacy of frequency doubling technology (FDT) perimetry for glaucoma detection in comprehensive screening examinations. We performed a retrospective analysis of prospectively collected data of participants who underwent a comprehensive health checkup service. Participants with glaucoma were excluded. In the first year, 2024 participants (46.8 ± 9.4 years) who underwent FDT perimetry and fundus photography were classified as the FDT group, whereas 3052 participants (42.2 ± 8.2 years) who underwent only fundus photography were classified as the non-FDT control group. Participants with abnormal findings on FDT perimetry and/or fundus photography were recommended to undergo further complete examination. All participants reported whether they had been newly diagnosed with glaucoma within 2 years of the first visit. In the FDT group, 23 (1.14%) participants were newly diagnosed with glaucoma. Among them, 20 (87.0%) had abnormal FDT perimetry findings and 12 (52.2%) had abnormal findings on fundus photography. The positive-predictive value (PPV) of FDT perimetry was 16.5% (20/121) and that of fundus photography was 13.3% (12/90). In participants with abnormal findings on both tests, the PPV was 26.2%. In the non-FDT group, 15 (0.49%) participants were newly diagnosed with glaucoma. Among them, 9 (60.0%) had abnormal findings on fundus photography. The PPV of fundus photography was 10.8% (9/83). The glaucoma detection rate, analyzed using age adjustment, was significantly higher in the FDT group than that in the non-FDT group (0.97% versus 0.47%, P=0.041). FDT perimetry, even if performed by nonspecialized physicians, could improve glaucoma detection when used in addition to fundus photography. This study was registered with UMIN000037951.

THE ROLE OF FREQUENCY DOUBLING TECHNOLOGY PERIMETRY IN EARLY DETECTION OF DIABETIC RETINOPATHY.

SUMMARYThe aim was to assess whether standard automated perimetry (SAP) and frequency doubling technology (FDT) perimetry are able to detect the effect of diabetes mellitus (DM) on retinal function in DM patients in the early stage of disease and to analyze which method is more specific and sensitive. A randomized cross-sectional study was conducted in three different groups of patients to compare the capability of these two methods to examine visual field and to detect the change in light sensitivity. Visual function was assessed in 60 adults with normal retinal finding, 60 adults with DM without clinically detectable retinopathy and 60 adults with DM and non-proliferative diabetic retinopathy but normal visual acuity. FDT perimetry and SAP were performed in all study patients. The presence and severity of diabetic retinopathy was determined by taking and evaluating two 50° field color photographs per eye, macula-centered and disc-centered. The following results were obtained by analyzing parameters in the groups of diabetic patients: sensitivity and specificity of SAP and FDT for medium sensitivity 86.7/33.3 (p<0.061) and 71.7/41.7 (p<0.228), respectively; for medium deficit 41.7/76.7 (p<0.063) and 65/50 (p<0.362), respectively; for loss of variance/pattern standard deviation (LV/PSD) 51.7/61.7 (p<0.536) and 61.7/51.7 (p<0.666), respectively; and for foveal sensitivity 81.7/36.7 (p<0.096) and 23.3/86.7 (p<0.839), respectively. Analysis of parameters between diabetics and control group yielded sensitivity and specificity for medium sensitivity 71.7/61.7 (p<0.001) and 70.8/55 (p<0.002), respectively; for medium deficit 56.7/60 (p<0.058) and 77.5/43.3 (p<0.037), respectively; for LV/PSD 58.3/58.3 (p<0.042) and 33.3/83.3 (p<0.437), respectively; and for foveal sensitivity 82.5/53.3 (p<0.001) and 28.3/85 (p<0.195), respectively. We concluded that neither of these methods was sensitive and specific enough to distinguish diabetics without retinopathy from diabetics with retinopathy. Both of these methods were highly specific and sensitive to distinguish diabetics from healthy subjects, but neither of these methods proved superior.