frequency doubling technology
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2022 ◽  
pp. 67-85
Author(s):  
Jacky K. W. Kong

Visual fields in the pediatric population are an essential part of the eye exam that remain challenging to even the most experienced clinicians. Becoming educated in the multiple ways a child's visual field can be tested regardless of age and cognitive and physical abilities will allow the clinician to gain better insight into the child's function and in some cases, allow the clinician to identify pathological or neurological anomalies in the visual pathway. Gross visual field or functional visual field extent can be estimated by tests such as confrontation visual field testing, finger counting field testing, and white sphere kinetic perimetry. For threshold measurements of a child's visual fields, the Goldmann perimeter, or the more advanced computerized tests such as the Humphrey perimeter, Octopus perimeter, or frequency doubling technology perimeter can be used. Modifications can be made to certain tests to better suit the child's cognitive and physical abilities. The chapter covers different methods of visual field testing specific for the pediatric population.


2021 ◽  
Vol 14 (2) ◽  
pp. 5-15
Author(s):  
Irina L. Simakova ◽  
Alfina R. Suleimanova ◽  
Natalya P. Baimuratova

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. 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). 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. 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.


2021 ◽  
Vol 20 (3) ◽  
pp. 21-29
Author(s):  
L. A. Grigoryan ◽  
I. L. Simakova ◽  
A. V. Kuroyedov

PURPOSE. To study the needs of practical ophthalmologists concerning the functionality and performance of automatic perimeters, and offer a possible solution to meet these needs.METHODS. An online survey of Russian ophthalmologists was organized and conducted. The survey was attended by specialists representing various medical institutions and medical research centers. As a result of the survey, 132 filled questionnaire forms were received and analyzed using the Kano and 4C models.RESULTS. According to experts, it is necessary for ophthalmologists to have an accessible automatic perimeter equipped with the screening (for the initial examination of patients) and threshold (to clarify the depth of photosensitivity disturbance of detected visual field defects) strategies. The general requirements for the functional characteristics of the screening and threshold tests of the automatic perimeter have been determined: small variability of repeated results, the speed and simplicity of the study — particularly, by employing the Frequency Doubling Technology (FDT), a non-standard perimetry technique. The requirements of users for the operational method of the automatic perimeter have been determined: absence of the need for a specially prepared room and place, mobility, portability, maximum ease of use to ensure the possibility of performing screening and primary diagnostics outside medical institutions, including by mobile medical teams, and also to allows examinations of individuals with disabilities, including bedridden patients, both in the hospital and at home.CONCLUSION. Based on the study data, the needs of ophthalmologists in the functional and operational characteristics of modern automatic perimeters were identified showing that the automatic perimeters presently used by modern medical institutions are far from optimal in terms of their properties/characteristics. These devices do not allow perimetry to be performed on patients with disabilities, including bedridden patients, neither at home nor in the hospitals. In addition, these devices require a darkened room, they are difficult to use, while their licensing documentation states that only ophthalmologists can conduct the examinations. Manufacturers do not offer solutions tailored to the individual needs of specific user groups — outpatient ophthalmologists who in particular work with disabled patients.


2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Ken Kitayama ◽  
Andrew G. Young ◽  
Alejandro Ochoa ◽  
Fei Yu ◽  
Kylie Yuen-Sum Wong ◽  
...  

2021 ◽  
Vol 14 (1) ◽  
pp. 75-87
Author(s):  
Irina A. Tikhonovskaya ◽  
Irina L. Simakova

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.


Author(s):  
Frédéric Dutheil ◽  
Cédric Benoist d’Azy ◽  
Bruno Pereira ◽  
Frederic Chiambaretta ◽  
Gil Boudet ◽  
...  

2020 ◽  
Vol 17 (2) ◽  
pp. 238-248
Author(s):  
N. A. Gavrilova ◽  
E. E. Ioyleva ◽  
N. S. Gadzhieva ◽  
O. E. Tishchenko ◽  
N. Yu. Kutrovskaya ◽  
...  

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.


2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Ryo Terauchi ◽  
Takashi Wada ◽  
Shumpei Ogawa ◽  
Masanobu Kaji ◽  
Tomohiro Kato ◽  
...  

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.


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