Which is the longest diameter of fetal skull?
Mentoveical is the distance between the tip of the mentum or chin and the most distant point of the veex. It is the longest diameter of the fetal skull and is 14cm long. It is the diameter of engagement in a brow presentation. Diameters of fetal skull: Occipitofrontal: It follows a line extending from a point just above the root of the nose to the most prominent poion of the occipital bone. 11.5cm Biparietal: It is the greatest transverse diameter of the head, which extends from one parietal boss to the other. 9.5cm. Bitemporal: It is the greatest distance between the two temporal sutures. 8cm. Occipitomental: It extends from the chin to the most prominent poion of the occiput. 12.5cm. Suboccipitobregmatic: It follows a line drawn from the middle of the large fontanel to the undersurface of the occipital bone just where it joins the neck. 9.5cm. Ref: Clinical Obstretics (10Th Edn.) By S. Gopalan, page 66, Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 4. Fetal Growth and Development. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e.
Biparietal
Bitemporal
Occipitomental
Mentoveical