Neuro-ophthalmological disorders in cerebral palsy: ophthalmological, oculomotor, and visual aspects.

Aim  Cerebral visual impairment (CVI) is a disorder caused by damage to the retrogeniculate visual pathways. Cerebral palsy (CP) and CVI share a common origin: 60 to 70\% of children with CP also have CVI. We set out to describe visual dysfunction in children with CP. A further aim was to establish whether different types of CP are associated with different patterns of visual involvement. Methods  A total of 129 patients (54 females, 75 males; mean age 4y 6mo, SD 3y 5mo; range 3mo-15y) with CP (51 with diplegia, 61 with tetraplegia, and 17 with hemiplegia; 62 [48\%] of participants were able to walk) and CVI enrolled at the Centre of Child Neuro-ophthalmology (at the Department of Child Neurology and Psychiatry, IRCCS 'C. Mondino Institute of Neurology', University of Pavia) underwent an assessment protocol including neurological examination, developmental and/or cognitive assessment, neuro-ophthalmological evaluation including ophthalmological assessment, evaluation of visual acuity, contrast sensitivity, optokinetic nystagmus, visual field and stereopsis, and neuroradiological investigations. Results  Visual dysfunction in diplegia was characterized mainly by refractive errors (75\% of patients), strabismus (90\%), abnormal saccadic movements (86\%), and reduced visual acuity (82\%). The participants with hemiplegia showed strabismus (71\%) and refractive errors (88\%); oculomotor involvement was less frequent (59\%). This group had the largest percentage of patients with altered visual field (64\%). Children with tetraplegia showed a severe neuro-ophthalmological profile, characterized by ocular abnormalities (98\%), oculomotor dysfunction (100\%), and reduced visual acuity (98\%). Interpretation  Neuro-ophthalmological disorders are one of the main symptoms in CP. Each clinical type of CP is associated with a distinct neuro-ophthalmological profile. Early and careful neuro-ophthalmological assessment of children with CP is essential for an accurate diagnosis and for personalized rehabilitation.