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Methods of visual field assessment
Published in Fiona Rowe, Visual Fields via the Visual Pathway, 2016
For full threshold testing, the stimulus intensity is increased in 4 dB steps until recorded and then decreased to below the threshold level and increased again until recorded, in 2 dB steps, to confirm the threshold level at that point. A full from prior strategy may also be used in some perimeters in which the last test to be performed is recalled and the threshold levels for each point from the last test are used as starting levels for the current test. The stimuli are initially started at a level 2 dB higher than the previous threshold and the test then continues as for a full threshold programme. The Humphrey FASTPAC strategy for threshold testing determines threshold sensitivity in 3 dB steps, thus speeding up the test process. This enables the patient to finish the test more quickly and this is an advantage where patient fatigue or illness is a problem. The Humphrey SITA (Swedish Interactive Thresholding Algorithm) uses full threshold and FASTPAC testing but is a faster method of assessing the visual field because of its interactive nature with patient responses and speed. SITA standard has a testing programme of 4 and 2 dB steps similar to the full threshold programme. SITA fast has a testing programme of 3 dB steps. SITA standard has been proven to provide as accurate and reliable field results as with normal full threshold fields and therefore can be recommended for routine visual field assessment (Wild et al. 1999).
Diurnal Spikes of Intraocular Pressure in Uveitic Glaucoma: A 24-hour Intraocular Pressure Monitoring Study
Published in Seminars in Ophthalmology, 2020
Fehim Esen, Muhsin Eraslan, Eren Cerman, Hande Celiker, Haluk Kazokoglu
Exclusion criteria included the presence of any coexisting retinal or optic nerve disease, ocular media opacities (which may affect the reliability of the retinal nerve fiber layer (RNFL) images and perimetry results), active ocular surface disease, presence of pterygium or other corneal disorders (for the reliability of CLS measurements), and a history of laser trabeculoplasty. None of the patients had a history of cataract, glaucoma or retinal surgery in the studied eye. The IOP of all patients was measured three times at each visit by the same physician (FE) using the GAT, and the average was listed. RNFL analysis was performed using optical coherence tomography (Optovue Inc., Foremont, CA); central corneal thickness (CCT) measurements were obtained with ultrasonic pachymetry (SP-3000, Tomey, Japan). Perimetry was performed in all patients with a Humphrey Visual Field Analyzer instrument [Carl Zeiss Inc., Dublin, CA]) with the Swedish Interactive Thresholding Algorithm standard 30–2 protocol. All patients exhibited mild glaucoma (MD<-6 dB). None of the patients had a history of neurological disease affecting the RNFL thickness or visual filed.
Methodology of the ZOC-BHVI High Myopia Cohort Study: The Onset and Progression of Myopic Pathologies and Associated Risk Factors in Highly Myopic Chinese
Published in Ophthalmic Epidemiology, 2018
Yanxian Chen, Ou Xiao, Xinxing Guo, Decai Wang, Padmaja Sankaridurg, Ian Morgan, Mingguang He
Visual field was examined using automatic perimetry (Zeiss Humphrey visual field 750i, Carl Zeiss Meditec Inc., Dublin, CA). All subjects performed Swedish interactive thresholding algorithm (SITA) fast 24-2 visual field test (white-on-white static perimetry). The examination was performed in a dark room (ambient light < 5 lux). An experienced technician explained the procedures of the test to each subject, and a short demonstration test can be performed in advance if necessary. During the test, the technician monitors the subject’s eye movement, and makes adjustments accordingly. Visual field defect and the underlying causes like retinochoroidal atrophy and glaucoma will be analyzed.
Stellate nonhereditary idiopathic foveomacular retinoschisis in an asymptomatic patient
Published in Clinical and Experimental Optometry, 2022
Thomas A Keith, Megan C Mills, Eric Tidmore
Reliable Humphrey 30-2 Swedish interactive thresholding algorithm standard visual field testing showed mild defects in the right eye, greater inferiorly than superiorly; and mild inferior nasal rim point defects in left eye. The patient was diagnosed with stellate nonhereditary idiopathic foveomacular retinoschisis after further evaluation by a retina specialist.