1. Children’s Oncology, Unit Marianna V. Vardinoyannis-ELPIDA, Aghia Sophia Children’s Hospital, 11527 Athens, Greece
2. Department of Otolaryngology, University Hospital of Patras, 26504 Patras, Greece
3. Department of Ophthalmology, Medical School, University of Patras, 26504 Patras, Greece
4. 1st Department of Otorhinolaryngology, Hippocration Hospital, University of Athens, 11527 Athens, Greece
5. Otolaryngology-Head & Neck Surgery, Athens Pediatric Center, 15125 Athens, Greece