Cross-sectional study on childhood cerebral visual impairment in New Zealand

Abstract

Purpose: To determine the prevalence, etiology, and avoidable causes of childhood cerebral visual impairment (CVI) in New Zealand.

Methods: The clinical and educational records of blind and low vision children enrolled in the Blind and Low Vision Education Network, New Zealand (BLENNZ), a national referral center, were retrospectively analyzed. The WHO Program for Prevention of Blindness (WHO/PBL) Eye Examination Record for Children with Blindness and Low Vision was used to record data from children ≤16 years of age diagnosed with CVI and visual acuity ≤6/18 enrolled with BLENNZ. Data analyzed included demographics, etiology, visual acuity, visual fields, educational setting, and rehabilitation plan.

Results: A total of 182 children (blind, 143; low vision, 39) were included. The calculated prevalence of childhood CVI in New Zealand was 0.02%. Of these, only 21% required low vision aids. Principle causes of CVI blindness were perinatal hypoxia/asphyxia (25%), nonaccidental injury (7%), and prematurity (7%). Approximately 50% of all cases of CVI blindness were potentially avoidable; of these, 52% were caused by perinatal hypoxia and 14% by nonaccidental injury.

Conclusions: The conservative calculated prevalence of CVI, responsible for 30% of all childhood blindness in New Zealand, was 0.02%. The most common cause of CVI blindness in New Zealand, perinatal asphyxia, is also an avoidable cause.