Morphometric Evaluation of Anterior Fontanelle: A Fetal Cadaveric Study

Background: The frontal bone is ossified from two primary centers, each half of the bone ossifies from a single center which appears between 6 and 7 weeks of the fetal life and is situated above the supra orbital margin. At birth the frontal bone is composed of two pieces, separated by the inter frontal suture and also separated from the parietal bones by the diamond-shaped, membrane filled anterior fontanelle that persists until 18 months after birth, which allows development and growth of the brain and the skull. Aim: The study was designed to measure the dimensions & extent of anterior fontanelle in fetal skulls in order to assess the dimensions of the fontanelle and its related clinical significance. Materials &Methods: The anterior fontanelle of 25 fetal skulls was studied, in the Department of Anatomy, Kasturba Medical College, and Manipal. The mean and standard deviation of the morphometric measures were tabulated. Results: In our study, the measurements of the antero posterior & transverse chord length measurements were done both in dry skull & pericranium of the scalp. The mean and standard deviations are determined. 25 dry skulls were placed in the exact environment considering the same distance, light source & angulation and photographed. The photographs were correlated with Digital image analyzer - TISSUE QUANT. The mean total surface area was calculated. Conclusion: Assessment of the tension and size of the anterior fontanelle is important in the routine examination of newborn infants when considering, respectively, possible disturbances of intracranial pressure and disorders of skeletal development. The knowledge of the normal variation in anterior fontanelle size may be of help in the early diagnosis of congenital hypothyroidism or provide a clue to other disorders of skeletal development.