1. Department of Anatomy, Histology and Embryology, Medical University Plovdiv, Vasil Aprilov Str. 15A, Plovdiv, 4002, Bulgaria
2. Department of Neurosurgery, Medical University Plovdiv, Plovdiv, Bulgaria
3. Medical University Plovdiv, Plovdiv, Bulgaria
4. Clinic of Fetopathology, Center for Maternity and Neonatology, Tunis, Tunisia