title: A comparison of pattern and multifocal electroretinography in the evaluation of age-related macular degeneration and its treatment with photodynamic therapy.
abstract: This study compares pattern electroretinography (PERG) and multifocal electroretinography (mfERG) measures in 13 patients with predominantly classic choroidal neovascularisation (CNV) associated with age-related macular degeneration (ARMD, 9/13 unilateral, 4/13 bilateral), assesses the usefulness of each test in monitoring disease progression, and identifies electrophysiological predictors of outcome following treatment with photodynamic therapy (PDT). PERG and mfERGs were recorded at presentation, 2 weeks post-treatment, and at 3 monthly intervals for 2 years. The PERG was detectable in 8/13 patients with unilateral disease; the mfERG was detectable in 12/13 patients. P50 and N95 amplitudes increased in 6/8 patients and mfERG p1 increased in 7/13 patients at 2 years. PERG amplitudes correlated strongly with mfERG amplitudes in patients with unilateral disease. PERG P50 and mfERG p1 amplitude correlated with visual acuity at 2 years (R = 0.68, R = 0.82, respectively). The largest PERG P50 and mfERG p1 amplitude difference between treated and fellow eyes of all the groups on initial visit was associated with a poor visual outcome (P50 64% difference; p1 29% difference) whereas those with the smallest P50 and p1 amplitude difference was associated with improved vision at 2 years (P50 30% difference; p1 21% difference). The PERG and mfERG provide an objective measure of central retinal function in the progression of ARMD. A detectable PERG on presentation was the single best indicator of improved function and visual acuity at 2 years. The mfERG demonstrated disease progression from central retina into the paramacular regions over 2 years. Patients with poor visual outcomes had the largest inter-ocular amplitude difference on presentation, suggesting that such patients may have a worse prognosis following treatment.
authors.affiliation: Moorfields Eye Hospital, London, EC1V 2PD, UK.
authors.forename: Magella M
authors.initials: MM
authors.lastname: Neveu
authors.forename: Adnan
authors.initials: A
authors.lastname: Tufail
authors.forename: Jonathan G
authors.initials: JG
authors.lastname: Dowler
authors.forename: Graham E
authors.initials: GE
authors.lastname: Holder
mesh_terms: D018450:Disease Progression; D004596:Electroretinography; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D005654:Fundus Oculi; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D008875:Middle Aged; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use; D011166:Porphyrins / Q000627:therapeutic use; D012160:Retina / Q000502:physiology*; D016896:Treatment Outcome; D000077362:Verteporfin
chemical_list: D017319:Photosensitizing Agents; D011166:Porphyrins; D000077362:Verteporfin