Occipitofrontal circumference

The data indicate that documentation of the OFC/crown-rump length (CRL) ratio is an effective way to determine if head circumference is in the normal range for a particular child's body size 1).

Increasing ventricular size-rather than classic clinical findings such as increasing occipitofrontal circumference (OFC), represents the threshold for either temporization or shunting of cerebrospinal fluid CSF in Intraventricular hemorrhage in the newborn.

CSF volume changes were not reflected in OFC changes.

Ventricle-skull ratio (VSR) was preferable over Evans ratio (ER) and bicaudate index (BCI), because it correlated more closely with CSF volume 2).

1)
Martins AM, Lyons Jones K. Correlation of occipitofrontal circumference and crown-rump length from birth to 15 months. Clin Dysmorphol. 1994 Apr;3(2):157-9. PubMed PMID: 8055136.
2)
van der Knaap MS, Bakker CJ, Faber JA, Valk J, Mali WP, Willemse J, Gooskens RH. Comparison of skull circumference and linear measurements with CSF volume MR measurements in hydrocephalus. J Comput Assist Tomogr. 1992 Sep-Oct;16(5):737-43. PubMed PMID: 1522266.