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Parul Ichhpujani, Hennaav Dhillon Department of Ophthalmology, Government Medical College and Hospital, Chandigarh, IndiaCorrespondence: Parul Ichhpujani, Department of Ophthalmology, Government Medical College and Hospital, Chandigarh, 160030, India, Tel +91-9501071591, Fax +91-172-2608488, Email parul77@rediffmail.comAbstract: Tablet based perimetry has the potential to be used as a low-cost, portable method for glaucoma screening. With the advent of tablets with large dynamic luminance range and high spatial resolution, perimetry applications can test visual field locations within the central 30 degrees, just like bowl perimetry. Tablet perimetry has garnered interest in this COVID era as it can be promptly done in the waiting room or even from the comfort of home. The current review focuses on evaluating glaucoma detection sensitivities, diagnostic abilities and correlation of each parameter and examination time of the iPad based perimetry applications with those of HFA.Keywords: visual field, standard automated perimetry, tablet perimetry, iPad

Mohammad Hasan Awwad, Ossama Nada, Momen Mahmoud Hamdi, Amany Abd El-Fattah El-Shazly, Sheriff Elwan Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, EgyptCorrespondence: Mohammad Hasan Awwad, Misr Lel Tayaran St., New Nozha, Cairo, 11843, Egypt, Tel +201003604524, Email dr_moh_awwad@hotmail.comPurpose: To investigate the correlation between the photopic negative response (PhNR) of the light-adapted flash electroretinography (ERG) and measurements of standard automated perimetry (SAP) and optical coherence tomography (OCT) in assessment of retinal ganglion cells’ (RGCs) affection in glaucoma.Patients and Methods: A cross-sectional study included 40 eyes of glaucoma patients and 40 eyes of age- and gender-matched normal subjects. Participants underwent a complete ophthalmologic assessment, SAP, OCT, and light-adapted flash ERG using the extended PhNR protocol of the International Society for Clinical Electrophysiology of Vision (ISCEV). Glaucomatous eyes were divided into 3 subgroups: mild (n = 15), moderate (n = 11) and severe glaucoma (n = 14) according to the mean deviation (MD) of SAP. Measurements of SAP, OCT and ERG parameters were analyzed, and correlations between PhNR measurements and other study measurements were evaluated.Results: PhNR amplitudes and PhNR/b-wave ratios were significantly reduced in glaucoma cases compared to healthy controls, and they showed a significant and progressive decline across the three glaucoma subgroups (P < 0.05). An exception to this is PT (b-wave peak to PhNR trough) PhNR amplitude where its reduction was statistically non-significant when comparing between controls and mild glaucoma cases (P = 0.178), and between moderate and severe glaucoma cases (P = 0.714). PhNR amplitudes and PhNR/b-wave ratios correlated significantly with SAP and OCT parameters (P < 0.05).Conclusion: PhNR correlates well with SAP and OCT parameters in glaucoma assessment. PhNR could be a valuable supplementary tool for objective assessment of the RGCs’ function in glaucoma.Keywords: glaucoma, retinal ganglion cells, standard automated perimetry, optical coherence tomography, photopic negative response, electroretinography

Introduction: The gold standard in functional glaucoma evaluation is standard automated perimetry (SAP). However, SAP depends on the reliability of the patients' responses and other external factors; therefore, other technologies have been developed for earlier detection of visual field changes in glaucoma patients. The frequency-doubling perimetry (FDT) is believed to detect glaucoma earlier than SAP. The multifocal visual evoked potential (mfVEP) is an objective test for functional evaluation. Objective: To evaluate the sensitivity and specificity of FDT and mfVEP tests in normal, suspect, and glaucomatous eyes and compare the monocular and interocular mfVEP. Methods: Ninety-five eyes from 95 individuals (23 controls, 33 glaucoma suspects, 39 glaucomatous) were enrolled. All participants underwent a full ophthalmic examination, followed by SAP, FDT, and mfVEP tests. Results: The area under the curve for mean deviation and pattern standard deviation were 0.756 and 0.761, respectively, for FDT, 0.564 and 0.512 for signal and alpha for interocular mfVEP, and 0.568 and 0.538 for signal and alpha for monocular mfVEP. This difference between monocular and interocular mfVEP was not significant. Conclusion: The FDT matrix was superior to mfVEP in glaucoma detection. The difference between monocular and interocular mfVEP in the diagnosis of glaucoma was not significant. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to compare the two perimetric modalities, SWAP (short wavelength automated perimetry) and SAP (standard automated perimetry), on the point of conversion to glaucoma. Methods: In this prospective, longitudinal, follow-up study, 282 patients with ocular hypertension were recruited consecutively and tested with both SAP and SWAP annually for 5 years or until the onset of conversion to glaucoma. SAP and SWAP perimetry was performed with the Humphrey Field Analyzer II using the 24-2 full-threshold test. Abnormality for both SAP and SWAP fields was determined on the pattern deviation plot and defined as either a) one point below the 0.5% probability level or b) a cluster of 2 or more points below 1% or c) a cluster of 3 or more points below 2% or d) a cluster of 4 or more points below 5%. Abnormal tests had to be confirmed on a subsequent test within one year to be classified as conversion. Results: Of the 282 patients initially recruited, 32 were excluded. Of the 250 remaining patients, a total of 38 converted during the follow-up period; 36.8% of conversions were detected earlier with SWAP, 29% simultaneously, and 34.2% were not detected with SWAP during the follow-up period; 2.4% of patients showed SWAP visual field loss that did not result in conversion during the follow-up period. Conclusion: The results in our study are inconclusive. There were patients with earlier, simultaneous, or no SWAP conversion, with SAP conversion as the golden standard criterion. One should consider both SAP and SWAP with confirmation when visual field loss is evident to maximize early detection of glaucoma, because it appears that each method identifies early glaucoma in a subset of patients and these subsets overlap only partially. [ABSTRACT FROM AUTHOR]