**2. Incidence**

Despite remarkable developments in diagnostic technologies and therapeutic modalities, the epidemiology of congenital CNS anomalies has not changed significantly. The prevalence of CNSA varies widely according to geographic regions and socioeconomic situations and is reported to be between 1 and 10 in every 1000 live births [7, 8]. The incidences of anencephaly and spina bifida per 10000 births range from 0.7 in central France to 0.9 in Canada, 7.7 in the United Arab Emirates, and 11.7 in South America [9]. A recently published systematic review and metaanalysis, which included 6558 infants, has reported a prevalence of occult spinal dysraphism (OSD) with cutaneous stigmata to be 2.8% [10].
