Dolichocephaly Long, narrow head SNOMEDCT_US:72239002 An abnormality of skull shape characterized by a increased anterior-posterior diameter, i.e., an increased antero-posterior dimension of the skull. Cephalic index less than 76%. Alternatively, an apparently increased antero-posterior length of the head compared to width. Often due to premature closure of the sagittal suture. UMLS:C4280653 UMLS:C0221358 UMLS:C4280655 UMLS:C4280654 UMLS:C4280656 Turridolichocephaly HP:0000268 HP:0005440 Narrow skull shape HP:0000258 Narrow cranium shape Cephalic index is the ratio of head width expressed as a percentage of head length. The normal range is 76-80.9%. Head length is measured between the glabella (the most prominent point on the frontal bone above the root of the nose) and the most prominent part of the occiput in the midline, using spreading calipers. Head width is measured between the most lateral points of the parietal bones on each side of the head, using spreading calipers. Cephalic index standards are derived from Caucasians and have limited relevance for other races and ethnicities. Current norms have limited validity because of changes in infant sleeping position and consequent changes in head shape. New data should be developed. Dolichocephaly is distinct from Prominent occiput, but both can be present in the same individual and should be coded separately. Scaphocephaly is a subtype of dolichocephaly where the anterior and posterior aspects of the cranial vault are pointed (boat-shaped). Narrow head shape Large dolichocephalic skull Tall and narrow skull Abnormal calvaria morphology