RT Journal Article
A1 Karanjia, Rustum
A1 Berezovsky, Adriana
A1 Sacai, Paula Yuri
A1 Cavascan, Nivea Nunes
A1 Liu, Henry Yuheng
A1 Nazarali, Samir
A1 Moraes-Filho, Milton Nunes
A1 Anderson, Kirsten
A1 Tran, Jeffrey Show
A1 Watanabe, Sung EunSong
A1 Moraes, Milton Nunes
A1 Sadun, Federico
A1 DeNegri, Anna Maria
A1 Barboni, Piero
A1 do Val Ferreira Ramos, Carolina
A1 La Morgia, Chiara
A1 Carelli, Valerio
A1 Belfort, Rubens, Jr
A1 Coupland, Stuart Glenn
A1 Salomao, Solange Rios
A1 Sadun, Alfredo A.
T1 The Photopic Negative Response: An Objective Measure of Retinal Ganglion Cell Function in Patients With Leber's Hereditary Optic NeuropathyPhNR as an Objective Measure in LHON
JF Investigative Ophthalmology & Visual Science
JO IOVS
YR 2017
DO 10.1167/iovs.17-21773
JF Investigative Ophthalmology & Visual Science
VO 58
IS 6
SP BIO300
OP BIO306
SN 1552-5783
AB    The photopic negative response (PhNR) is a slow negative component of a flash photopic full-field ERG that has been shown to be specific for retinal ganglion cell (RGC) activity. Direct evaluation of RGC function is desirable in patients with Leber's hereditary optic neuropathy (LHON) in which the loss of central acuity can make it difficult to monitor patients with standard metrics. The purpose of this study was to evaluate the use of PhNR as an objective noninvasive clinical metric in LHON.    Full-field photopic ERG recordings were collected in subjects with the mt.11778G>A/ND4 LHON mutation using a red on blue stimulus. The PhNR was identified using a computer-based automated detection system, and data were manually examined to remove movement artifacts.    The PhNR amplitude was compared between controls (n = 13), carriers (n = 17), and affected (n = 6). Mean PhNR amplitude decreased significantly across groups (P < 0.0001). Post hoc Tukey's test revealed a significant decrease in PhNR amplitude between carriers and controls (P < 0.05) and between carriers and affected (P < 0.01).    We are able to demonstrate that the PhNR amplitude is significantly decreased in patients affected by LHON compared to carriers in a well-described pedigree. Surprisingly, there was also a decrease in PhNR in carriers, suggesting potential subclinical RGC dysfunction in some carriers. This is important in patients affected with LHON who typically have a dense central scotoma. The PhNR may be a useful objective outcome measure for future clinical trials.  
RD 2/17/2019
UL https://dx.doi.org/10.1167/iovs.17-21773