Eye and Brain (Oct 2020)
Neurofibromatosis Type 1: Ocular Electrophysiological and Perimetric Anomalies
Abstract
Marcella Nebbioso,1,* Antonietta Moramarco,1,* Alessandro Lambiase,1 Sandra Giustini,2 Marco Marenco,1 Emanuele Miraglia,2 Pasquale Fino,2 Chiara Iacovino,2 Ludovico Alisi1 1Department of Sense Organs, Sapienza University of Rome, Rome, Italy; 2Department of Dermatology, Sapienza University of Rome, Rome, Italy*These authors contributed equally to this workCorrespondence: Alessandro LambiaseDepartment of Sense Organs, Sapienza University of Rome, Viale del Policlinico 155, Rome 00161, ItalyTel +390649975357Fax +390649975425Email [email protected]: Neurofibromatosis type 1 (NF1) is a multisystemic disease caused by the mutation of Nf1 gene located on chromosome 17q11.2. The mutation determines the loss of function of the protein neurofibromin with consequent uncontrolled cellular proliferation. Patients are characterized by a wide range of dermatological, neurological, and ophthalmological symptoms.Purpose: The aim of the study was to evaluate, through pattern visual evoked potentials (p-VEPs) and frequency doubling technology (FDT) Matrix perimetry, the objective and psychophysical functionality of the optic pathways in a group of NF1 patient.Methods: The study group consisted of 26 patients affected by NF1 and 17 healthy controls. Each patient underwent a complete ophthalmological examination, p-VEPs with the evaluation of amplitude and latency of the P100 wave, and FDT perimetry, with the evaluation of central sensitivity (CS), mean deviation (MD), pattern standard deviation (PSD) and glaucoma hemifield test (GHT).Results: NF1 patients showed a statistically significant alteration in the transmission of visual impulse. P-VEPs results highlighted a reduced amplitude and an increased latency of the P100 wave, suggesting an involvement of the visual pathway. Visual field analysis showed a significant reduction in all the observed parameters as well (CS, MD, PSD, and GHT).Conclusion: The present study showed, in NF1 patients, a qualitative and quantitative alteration in the conduction of stimuli through the visual pathways. The observed alterations are present, although, only at a subclinical level. None of the patients included in the study showed any manifest visual deficit nor had any concomitant pathology that might have affected the outcome of the study. In conclusion, electrophysiological exams and computer perimetry may take part, alongside a wider array of exams, in the differential diagnosis and later monitoring of NF1.Keywords: electrophysiologic testing, frequency doubling technology Matrix perimetry, FDT, neurofibromatosis type 1, optic glioma, pattern visual evoked potentials
