scholarly journals PERG adaptation for detection of retinal ganglion cell dysfunction in glaucoma: a pilot diagnostic accuracy study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
T. Salgarello ◽  
G. M. Cozzupoli ◽  
A. Giudiceandrea ◽  
A. Fadda ◽  
G. Placidi ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Roc Curves ◽  
Normal Subjects ◽  
Retinal Ganglion ◽  
Angular Dispersion ◽  
Recording Time ◽  
Adaptive Changes ◽  
Grand Average

AbstractIt has been previously demonstrated that the adaptive phase changes of steady-state pattern electroretinogram (SS-PERG), recorded during 4-min presentation of patterned stimuli, are reduced in glaucoma suspects and patients compared to normal subjects. Our study aims at testing the hypothesis that adaptive changes of SS-PERG, recorded using the novel optimized Next Generation PERG (PERGx) protocol, differ between glaucoma patients and controls. In this pilot cross-sectional study, we included 28 glaucoma patients and 17 age-matched normal subjects. Both patients and controls underwent a full ophthalmologic examination, visual field testing, OCT and PERGx. The PERGx signal was sampled over 2 min (providing 1 noise and 9 signal packets) in response to alternating gratings generated on an OLED display. PERGx amplitude and phase were analyzed to quantify adaptive changes over recording time. Receiver operating characteristic (ROC) curves were used to study the diagnostic accuracy of PERGx parameters in distinguishing glaucoma patients from normal subjects. PERGx amplitude and phase data showed declining trends in both groups. PERGx amplitude slope and grand-average vector amplitude and phase were significantly different in patients compared to controls (p < 0.01), whereas phase angular dispersion was greater in patients but not significantly different between the two groups. The area under the ROC curves were 0.87 and 0.76 for PERGx amplitude slope and grand-average vector amplitude, and 0.62 and 0.87 for PERGx angular dispersion and grand-average vector phase, respectively. The PERGx paradigm resulted highly accurate in detecting the reduction of amplitude adaptive changes in glaucoma patients, presumably due to the loss of functional retinal ganglion cell autoregulation. Thus, PERG adaptation, recorded by this new protocol, might be helpful in the identification and diagnosis of early glaucomatous dysfunction.

scholarly journals A Perg Adaptation Paradigm for Detection of Retinal Ganglion Cell Dysfunction in Glaucoma Patients.

2021 ◽  
Author(s):  
Tommaso Salgarello ◽  
Grazia Maria Cozzupoli ◽  
Andrea Giudiceandrea ◽  
Fadda Antonello ◽  
Giorgio Placidi ◽  
...  
Keyword(s):  
Pattern Electroretinogram ◽  
Roc Curves ◽  
Field Testing ◽  
Normal Subjects ◽  
Cross Sectional Study ◽  
Phase Changes ◽  
Cross Sectional ◽  
Recording Time ◽  
Adaptive Changes ◽  
Grand Average

Abstract Purpose: It has been previously demonstrated that the adaptive phase changes of steady-state pattern electroretinogram (SS-PERG), recorded during 4-minute presentation of patterned stimuli, are reduced in glaucoma suspects and patients compared to normal subjects. Our study aims at testing the hypothesis that adaptive changes of SS-PERG, recorded using the novel optimized Next Generation PERG (PERGx) protocol, differ between glaucoma patients and controls.Methods: In this pilot cross-sectional study, we included 28 glaucoma patients and 17 age-matched normal subjects. Both patients and controls underwent a full ophthalmologic examination, visual field testing, OCT and PERGx. The PERGx signal was sampled over 2 minutes (providing 1 noise and 9 signal packets) in response to alternating gratings generated on an OLED display. PERGx amplitude and phase were analyzed to quantify adaptive changes over recording time. Receiver operating characteristic (ROC) curves were used to study the diagnostic accuracy of PERGx parameters in distinguishing glaucoma patients from normal subjects.Results: PERGx amplitude and phase data showed declining trends in both groups. PERGx amplitude slope and grand-average vector amplitude were significantly lower in patients compared to controls (p < 0.01). The area under the ROC curves of PERGx amplitude slope and grand-average vector amplitude were 0.87 and 0.76, respectively.Conclusion: The PERGx paradigm resulted highly accurate in detecting the reduction of amplitude adaptive changes in glaucoma patients, presumably due to the loss of functional RGC autoregulation. Thus, PERG adaptation, recorded by this new protocol, might be helpful in the identification and diagnosis of early glaucomatous dysfunction.

scholarly journals The Estimates of Retinal Ganglion Cell Counts Performed Better than Isolated Structure and Functional Tests for Glaucoma Diagnosis

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Bruno L. B. Esporcatte ◽  
Andrea C. Kara-José ◽  
Luiz Alberto S. Melo ◽  
Luciano M. Pinto ◽  
Ivan M. Tavares
Keyword(s):  
Diagnostic Accuracy ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Automated Perimetry ◽  
Retinal Ganglion ◽  
Average Thickness ◽  
Healthy Individuals ◽  
Combining Data ◽  
Better Than ◽  
Sd Oct

Purpose. To evaluate the diagnostic accuracy of retinal ganglion cell (RGC) counts as estimated by combining data from standard automated perimetry (SAP) and spectral domain optical coherence tomography (SD-OCT).Methods. Healthy individuals and glaucoma patients were included in this cross-sectional study. All eyes underwent 24-2 SITA SAP and structural imaging tests. RGC count estimates were obtained using a previously described algorithm, which combines estimates of RGC numbers from SAP sensitivity thresholds and SD-OCT retinal nerve fiber layer (RNFL) average thickness.Results. A total of 119 eyes were evaluated, including 75 eyes of 48 healthy individuals and 44 eyes of 29 glaucoma patients. RGC count estimates performed better than data derived from SD-OCT RNFL average thickness or SAP mean deviation alone (area under ROC curves: 0.98, 0.92, and 0.79;P<0.001) for discriminating healthy from glaucomatous eyes, even in a subgroup of eyes with mild disease (0.97, 0.88, and 0.75;P<0.001). There was a strong and significant correlation between estimates of RGC numbers derived from SAP and SD-OCT (R2=0.74;P<0.001).Conclusion. RGC count estimates obtained by combined structural and functional data showed excellent diagnostic accuracy for discriminating the healthy from the glaucomatous eyes and performed better than isolated structural and functional parameters.

scholarly journals OPTICAL COHERENCE TOMOGRAPHY

2016 ◽  
Vol 23 (09) ◽  
pp. 1149-1156
Author(s):  
Faheem Ahmad ◽  
Muhmmad Hussian
Keyword(s):  
Optic Nerve ◽  
Diagnostic Accuracy ◽  
Ganglion Cell ◽  
Retinal Ganglion Cell ◽  
Optic Nerve Head ◽  
Predictive Value ◽  
Structural Changes ◽  
Retinal Ganglion ◽  
Fiber Layer ◽  
Cross Sectional

“Glaucoma an optic neuropathy is a caused by progressive retinal ganglion cell(RGC) loss associated with characteristic structural changes in the optic nerve and retinal nervefiber layer (RNFL).Glaucoma induced damage causes the retinal ganglion cells loss that canresult in functional loss and decrease in vision of patient . Measurement of intraocular pressureby Tonometery, characteristics of the optic nerve head changes and associated visual fieldloss are used for diagnosis of Glaucoma. Objectives: To determine the diagnostic accuracy ofOptical Coherence Tomography in detection of glaucoma taking perimetry as gold standard.Study Design: Cross sectional (validation). Period: Six months from 17-02-2014 to 16-08-2014.Material and Method: Regarding the Inclusion Criteria patients of glaucoma suspects that meetthe criteria mentioned in operational definition of either gender with age range between 35- 60years were included while patients having refractive errors, hazy media, pupil size less than4mm after dilation were not included in this study. Also patients with history diabetes mellitus,refractive or retinal surgery were also excluded. All the data was entered and analyzed by usingSPSS V-16. Results: A total of 100 patients were included in this study during the study period.Majority of the patients were between 35-45 years of age and minimum patients were 56-60 years old. Mean age of the patients was 47.10±8.02 years. Males and females were 50(50%). At OCT glaucoma was present in 71 patients while at perimetry glaucoma was presentin 69 patients .Sensitivity, specificity and diagnostic accuracy of OCT was 92.7%, 77.4%, 88.0%,respectively .Positive predictive value and negative predictive value of OCT was 90.1% and82.7%, respectively. Discussion: Regarding the pathogenesis of Glaucoma induced damageis due to result of retinal ganglion cell (RGC) death with progressive loss of axons located inthe retinal nerve fiber layer (RNFL). Many clinical studies showed that optic nerve head (ONH)damage and thinning of the RNFL occur earlier than the appearance of Glaucoma inducedvisual field defects; Conclusion: In conclusion, glaucoma suspects undergoing the OCT canbe assessed for the presence of glaucoma based purely on the results of the OCT.

The metalloproteinase ADAM10 is required for retinal ganglion cell axon guidance in the developing visual systems

2007 ◽  
Vol 30 (4) ◽  
pp. 77
Author(s):  
Y. Y. Chen ◽  
C. L. Hehr ◽  
K. Atkinson-Leadbeater ◽  
J. C. Hocking ◽  
S. McFarlane
Keyword(s):  
Ganglion Cell ◽  
Axon Guidance ◽  
Retinal Ganglion Cell ◽  
Growth Cone ◽  
Expression Patterns ◽  
Optic Tract ◽  
Axon Growth ◽  
Proteolytic Processing ◽  
Retinal Ganglion

Background: The growth cone interprets cues in its environment in order to reach its target. We want to identify molecules that regulate growth cone behaviour in the developing embryo. We investigated the role of A disintegrin and metalloproteinase 10 (ADAM10) in axon guidance in the developing visual system of African frog, Xenopus laevis. Methods: We first examined the expression patterns of adam10 mRNA by in situ hybridization. We then exposed the developing optic tract to an ADAM10 inhibitor, GI254023X, in vivo. Lastly, we inhibited ADAM10 function in diencephalic neuroepithelial cells (through which retinal ganglion cell (RGC) axons extend) or RGCs by electroporating or transfecting an ADAM10 dominant negative (dn-adam10). Results: We show that adam10 mRNA is expressed in the dorsal neuroepithelium over the time RGC axons extend towards their target, the optic tectum. Second, pharmacological inhibition of ADAM10 in an in vivo exposed brain preparation causes the failure of RGC axons to recognize their target at low concentrations (0.5, 1 μM), and the failure of the axons to make a caudal turn in the mid-diencephalon at higher concentration (5 μM). Thus, ADAM10 function is required for RGC axon guidance at two key guidance decisions. Finally, molecular inhibition of ADAM10 function by electroporating dn-adam10 in the brain neuroepithelium causes defects in RGC axon target recognition (57%) and/or defects in caudal turn (12%), as seen with the pharmacological inhibitor. In contrast, molecular inhibition of ADAM10 within the RGC axons has no effect. Conclusions: These data argue strongly that ADAM10 acts cell non-autonomously within the neuroepithelium to regulate the guidance of RGC axons. This study shows for the first time that a metalloproteinase acts in a cell non-autonomous fashion to direct vertebrate axon growth. It will provide important insights into candidate molecules that could be used to reform nerve connections if destroyed because of injury or disease. References Hattori M, Osterfield M, Flanagan JG. Regulated cleavage of a contact-mediated axon repellent. Science 2000; 289(5483):1360-5. Janes PW, Saha N, Barton WA, Kolev MV, Wimmer-Kleikamp SH, Nievergall E, Blobel CP, Himanen JP, Lackmann M, Nikolov DB. Adam meets Eph: an ADAM substrate recognition module acts as a molecular switch for ephrin cleavage in trans. Cell 2005; 123(2):291-304. Pan D, Rubin GM. Kuzbanian controls proteolytic processing of Notch and mediates lateral inhibition during Drosophila and vertebrate neurogenesis. Cell 1997; 90(2):271-80.

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