title: Functional Loss of the Inner Retina in Childhood Optic Gliomas Detected by Photopic Negative Response.
abstract: OBJECTIVE
  To determine whether the Ganzfeld ERG photopic negative response (PhNR), an assay of inner retinal activity, is altered in childhood optic glioma (OPG).
  
  
  METHODS
  Seventeen pediatric patients with a diagnosis of OPG, established on neuro-ophthalmologic and brain/orbit magnetic resonance imaging (MRI) criteria, were enrolled. The examination protocol included determination of visual acuity (VA), fundus examination, retinal nerve fiber layer (RNFL) measurement with spectral-domain optical coherence tomography (SD-OCT) and photopic ERG. Fifteen normal children served as control group. Ten of the 17 OPG patients were retested 1 to 3 months after the first examination. Photopic ERGs were recorded after 10 minutes of light adaptation in response to a Ganzfeld flash presented on a steady light-adapting background. Amplitude and peak-time of b-wave and PhNR were measured.
  
  
  RESULTS
  Compared with normal values, PhNR amplitude was significantly reduced (P < 0.0001) in the OPG group. Peak-time of PhNR as well as b-wave amplitude and peak-time were similar in both patients and controls. Losses of PhNR were found in patients with involvement of either anterior or retro-chiasmatic optic pathways. Linear regression analysis showed significant positive correlation between RNFL thickness and PhNR amplitude (r2 = 0.34, P = 0.008). Mean percentage test-retest difference for PhNR amplitude and peak-time was 12% and 6%, respectively.
  
  
  CONCLUSIONS
  These findings indicate that flash ERG PhNR can detect a loss of inner retinal function in childhood OPGs supporting the use of this technique, as an adjunct to standard psychophysical and electrophysiological tests, to monitor visual function in OPG.
authors: Department of Ophthalmology, Catholic University of Sacred Heart, Rome, Italy.
authors: Edoardo
authors: E
authors: Abed
authors: Department of Ophthalmology, Catholic University of Sacred Heart, Rome, Italy.
authors: Marco
authors: M
authors: Piccardi
authors: Department of Pediatrics, Catholic University of the Sacred Heart, Rome, Italy.
authors: Daniela
authors: D
authors: Rizzo
authors: Department of Pediatrics, Catholic University of the Sacred Heart, Rome, Italy.
authors: Antonio
authors: A
authors: Chiaretti
authors: Department of Ophthalmology, Catholic University of Sacred Heart, Rome, Italy.
authors: Lucia
authors: L
authors: Ambrosio
authors: Department of Ophthalmology, Bambino Gesù Children's Hospital, Rome, Italy.
authors: Sergio
authors: S
authors: Petroni
authors: Department of Ophthalmology, Catholic University of Sacred Heart, Rome, Italy.
authors: Rosa
authors: R
authors: Parrilla
authors: Department of Ophthalmology, Catholic University of Sacred Heart, Rome, Italy.
authors: Anna
authors: A
authors: Dickmann
authors: Department of Pediatrics, Catholic University of the Sacred Heart, Rome, Italy.
authors: Riccardo
authors: R
authors: Riccardi
authors: Department of Ophthalmology, Catholic University of Sacred Heart, Rome, Italy.
authors: Benedetto
authors: B
authors: Falsini
mesh_terms: D000221:Adaptation, Ocular / Q000502:physiology*; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D055253:Color Vision / Q000502:physiology*; D004596:Electroretinography; D005260:Female; D006801:Humans; D008297:Male; D020339:Optic Nerve Glioma / Q000175:diagnosis / Q000503:physiopathology*; D010775:Photic Stimulation / Q000379:methods; D012165:Retinal Ganglion Cells / Q000502:physiology*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity; D014794:Visual Fields