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Visual Fields in Neuro-Ophthalmology
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Perimetry is the technique of quantitatively assessing the field of vision.3 It has advantages over confrontation visual field analysis in terms of accuracy but also in proving quantitative information so that change over time can be monitored.2,3 It is important to understand the technique that has been used to be able to interpret the information provided and appreciate the limitations of the technique. When interpreting the output of perimetry, it is important to view the results from both eyes at the same time with the left eye visual field placed to the left and the right eye to the right. In this way, the plots are viewed from the perspective of the subject looking into the test bowl. By doing this both differences and similarities between the outputs from each eye can be interpreted, which may be very subtle. The identity of the patient having the test needs to be confirmed as well as the date on which it was performed.5
Introduction
Published in Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza, Computer-Aided Glaucoma Diagnosis System, 2020
Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza
Visual field testing (perimetry) is a test that measures the patient’s vision. The patient will look straight ahead at a small light and will then be asked to tell the examiner when he sees a light flash to the side of his peripheral vision.
Basic science, investigations and lasers
Published in Mostafa Khalil, Omar Kouli, The Duke Elder Exam of Ophthalmology, 2019
Tarek Khalil, Bilal Ibrahim, Stewart Gillan, Obaid Kousha
Perimetry is used to detect visual field defects and is commonly used in glaucoma and neuro-ophthalmic conditions. Examples of perimetry include Humphrey visual field analysis or Goldmann visual field testing.
Isolated optic neuritis after pembrolizumab administration for non-small-cell lung carcinoma
Published in International Journal of Neuroscience, 2022
Olga E. Makri, Foteinos-Ioannis Dimitrakopoulos, Foteini Tsapardoni, Iasonas Tsekouras, Andreas A. Argyriou, Haralabos Kalofonos, Constantine D. Georgakopoulos
Consequently, the presenting optic neuritis was considered as a highly probable (score 7) pembrolizumab-related adverse event, according to the Naranjo nomogram [7] and discontinuation of the drug was decided. The patient received, as inpatient, 1 gr intravenous methylprednisolone for 3 consecutive days, resulting in BCVA improvement to 20/25 in OD and 20/40 in OS. He was then discharged with a regimen of oral prednisolone (0.5 mg/Kg/day). Three weeks after presentation, BCVA improved to 20/22 in OD and 20/33 in OS. Fundoscopy revealed resolution of optic disc edema in OS with some residual hyperemia in the inferior nasal quadrant of the optic nerve head (Figure 1(c)). In perimetry the defects persisted but indices exhibited subtle improvement. The MD was −10.28 dB in OD and −13.44 dB in OS. The RNFL thickness in OS decreased. At that time tapering of prednisone by 5 mg per week was initiated. At 2 months follow-up, while patient was under treatment with 10 mg/day prednisolone, BCVA was 20/25 in OD and 20/22 in OS. The prednisone dosage was finally decreased to 5 mg/day for one week and then discontinued. Three months after the onset of symptoms and while the patient had been off steroid treatment for 3 weeks, BCVA was 20/28 in OD and 20/25 in OS. Fundoscopy was normal in both eyes (Figure 1(d)). Perimetry revealed a relative improvement of the visual field defects. The MD was −8.57 dB in OD and −9.64 dB in OS (Figure 1e, f). Re-challenge with pembrolizumab was omitted throughout.
A case of undiagnosed craniopharyngioma
Published in Clinical and Experimental Optometry, 2022
Bitemporal visual field defects are a hallmark feature of chiasmal compression, although other patterns of field loss can ensue.5,6 Many patients, however, are often unaware of visual changes and can frequently compensate for gradual loss. Even substantial and established field loss can go unnoticed as demonstrated in this case. Children are also frequently inattentive to vision problems. A quick and simple screening field test, such as confrontation, may detect gross visual field defects. The limitations of field testing by confrontation however are well known particularly in detecting subtle and early visual field loss. Numerous other visual field screening techniques, including app-based tools, can be employed for improved sensitivity. Nevertheless, quantitative perimetry is indicated in the presence of reduced acuity, ocular misalignment and/or headaches, even with a clear screening test result.
Outcomes measures in idiopathic intracranial hypertension
Published in Expert Review of Neurotherapeutics, 2021
Susan P Mollan, Alexandra J Sinclair
Automated perimetry is an objective measure of the visual field, widely used in clinical practice [42]. Importantly, there are a number of factors that make visual fields unreliable to interpret in IIH. The visual field type, either static or kinetic, and the program settings significantly affect the pick-up of defects depending on the visual field strategy [43], with a preference for automated perimetry for a more sensitive pick up rate [44]. The visual field test is dependent on technician and patient performance and is prone to variability and inaccuracy [45,46]. Initially patients can perform poorly on automated perimetry [45], and many trials sanction multiple attempts for familiarization and learning [46,47]. In the IIHTT, up to 21% of patients had a performance failure at one data point [45]. For IIH there is a further complicating factor in the interpretation of visual fields with the high prevalence of functional vision loss presenting as non-organic visual fields in this disease [47,48]. Cognitive deficits have also been reported in IIH [49] and have shown deficits in key areas such as memory, learning, visuospatial skills, concentration, language and executive function [50–54]. Deficits in reaction time and processing speed have also been demonstrated, which could impact on those with IIH to perform visual fields reliably [50]. Cognitive deficits have been demonstrated to affect the performance of visual fields in other diseases [55,56].