Hybrid surgery for scaphocephaly with distraction osteogenesis using skull expanders: technical note.

BACKGROUND: The authors described their surgical technique for scaphocephaly in relatively older infants who are 5 months old or over. The technique is a kind of hybrid of distraction osteogenesis utilizing skull expanders and a traditional cranial reconstruction procedure. SURGERY: The surgery usually consists of four procedures. The first is to make strip craniotomy over the superior sagittal sinus (SSS) from the major fontanelle to the minor one. The second is the occipital craniotomy for the occipital bossing. The occipital bone flap undergoes barrel stave osteotomy and is repositioned later. The third is placement of skull expander for distraction osteogenesis. Bidirectional small strip craniotomy is made along the coronal and lambdoid sutures, then transverse cutting is added to make a hinge point near the base of the parietal bone. Two to three skull expanders are placed crossing the SSS. The last procedure is radial-oriented osteotomy on the dorsal end of frontal bone to meet the elevated, expanded parietal bone. Skull expansion starts within a week with 5 mm/week base up to 20 to 30 mm. Exposed shafts of the expander are cut at the end of skull expansion. DISCUSSION: Process of osteogenesis is followed at an outpatient clinic, and the expanders are removed 4 to 6 months later after confirming the sufficient ossification. An advantage of our procedure is that maximum skull expansion is possible with minimum regression after distraction osteogenesis in the long term. Limited craniotomy enables limited blood loss. The skin trouble caused by stretching can be avoided. No postoperative helmet is required. A disadvantage is that the procedure leaves a foreign body on the skull for several months and requires additional surgery for removal.