1. Pediatrics, Referral Center for Sickle Cell Disease, Centre Hospitalier Intercommunal, Créteil, France;
2. Hematology, Saint-Louis Hospital, Paris, France;
3. Radiology, Centre Hospitalier Intercommunal, Créteil, France;
4. Department of Statistics, St-Louis Hospital, Paris, France;
5. Biochemistry, Henri Mondor Hospital, Créteil, France;
6. Pediatrics, University of Southern California, Los Angeles, Los Angeles, California; and
7. Hematology, Henri Mondor Hospital, Créteil, France