Crouzon syndrome: quantitative assessment of presenting deformity and surgical results based on CT scans

We reviewed our experience with 14 children who presented sequentially with untreated Crouzon syndrome and whose cranial vault presentation was with bilateral coronal synostosis. Using a method of 14 measurements in the cranio-orbitozygomatic region taken from preoperative and postoperative CT scans in these patients, we documented their presenting skeletal morphology and the results of surgical correction at least 1 year after operation. Our preoperative measurements confirmed a widened anterior cranial vault at 108 percent of normal and a cranial length averaging only 92 percent of normal. In comparison with age-matched controls, orbital measurements revealed a widened anterior interorbital distance at 122 percent of normal, an increased intertemporal width at 121 percent of normal, globe protrusion at 119 percent of normal, and a short medial orbital wall distance at only 86 percent of normal. The distance between the zygomatic buttresses and the interarch distance were found to be increased at 106 and 103 percent of normal, respectively. The zygomatic arch lengths were substantially shortened at only 87 percent of age-matched control values. These findings confirmed clinical observations of brachycephalic anterior cranial vaults with shallow, hyperteloric orbits and globe proptosis. Generally, in these patients the midface is horizontally retrusive and transversely wide, reflected in wide and shortened zygomas. Assessment of the postoperative results at least 1 year later showed no significant changes in any craniofacial measurements. Our findings indicate that early surgical attempts to decompress and reshape the cranio-orbital regions may limit the effects of increased intracranial pressure but do not correct the deformity as judged by CT scan evaluation at least 1 year later. Over the period of the study, the Crouzon deformity did not worsen after surgery, but the measurements remained far from normal.