Visual Allesthesia in a Patient with Glioblastoma Multiforme

Purpose: To report a rare case of visual allesthesia in a patient with glioblastoma multiforme. Material - Methods : A 46 – year old male presented in emergency ophthalmologic department complaining for difficulties in performing tasks related to color discrimination in his occupation (PC technician). The patient underwent a thorough ophthalmological examination and then he was referred to the neurological department for further evaluation. Results: The patient presented an atypical pattern of color perception disturbance. His best corrected visual acuity decreased progressively during hospitalization. He also experienced visual allesthesia paroxysmally (illusory left homonymous transpositions of subjects viewed in the right homonymous visual field). The visual field evaluation revealed homonymous left hemianopsia. Magnetic resonance imaging revealed glioblastoma multiforme confirmed by biopsy. Conclusions: A thorough ophthalmological and neuro-imaging control is suggested in patients with sudden color perception disturbance. Patients with temporal or occipital cortex damage may experience visual allesthesia.