Relation between Intracranial Volume and the Surface Area of the Foramen Magnum

Abstract

Several investigators have estimated the intracranial volume (ICV) in the past which indirectly reflects the brain volume. Most of these studies have been made on the dry skulls using linear dimensions, packing methods or occasionally radiological methods. It is also reported that the etiology of cerebellar tonsillar herniation is closely related to the size of the foramen magnum (FM). In the present study the ICVs have been estimated in 28 dry skulls using filling water method and the surface area of FMs were measured planimetry method. The estimated mean ICV was 1,311 +/- 133 cm. Surface area of FM was 760 +/- 144 mm. Antero-posterior and lateral direct roentgenograms of the skulls were also taken and the width, height and length (WHL) of the skull were measured by means of the cephalometry on radiograms. The relationship between the ICV, WHL and surface area of FM were analyzed statistically. The ICV, WHL and surface area of FM was correlated well (r = 0.271, P < 0.005; r = 0.265, P < 0.005, respectively) and a regression formula was proposed. Our results showed that skulls with larger ICV and WHL have larger FM surface area. We also suggested a regression formula that could be used to predict the surface area of FM regarding to the ICV and WHL values. In the next step, we took roentgenograms of skulls and obtain ICV measuring the width, length and height of skulls by means of cephalometry and investigate the relation between the findings of cephalometry and surface area of FM. The cephalometry could apply on living subjects and, thereby, our findings could provide some data to evaluate the etiology of Arnold Chiari malformation and achondroplasia for living subjects.

Correlation of Skull Size and Brain Volume, with Age, Weight, Height and Body Mass Index of Arak Medical Sciences Students

“…However, Golalipoor et al (2005) have reported skull volume to be 1420.60± 85 cm 3 in males and 1227.2±120 cm 3 in Turkmen race of Gorgan, which is closer to our study compared to the mentioned Indian study. Acer et al (2006) calculated the internal skull volume to be 1311±133 cm 3 which is close to amount achieved in the present study (1276.94±310 cm 3 ). In regression analysis of our study, we found that age and BMI in young males and females is positively correlated with brain volume which supports the results of Gustafson's study (Gustafson et al, 2004).…”

Morphometric analysis of the foramen magnum using cone beam computed tomography

“…The underlying reason is that these measurements provide clear images of skeletal features in cases where flesh is present (19,20). Two-dimensional imaging methods including antero-posterior and lateral cephalometric radiographs have been generally used in previous studies for skull measurements (18). The use of three-dimensional radiographic images like medical computed tomography (CT) has become more common in recent years (6,(20)(21)(22)(23).…”

Estimation of Cranial Capacity in 17-26 Years Old University Students

“…Some of the investigators have estimated the CC in the past which indirectly reflects the brain volume (Gault et al, 1988;Wolf et al, 2003;Mazonakis et al, 2004). One of the most satisfactory method for measuring CC of a dry skull is measuring the amount of water poured into a balloon which introduced into the cranial cavity through the foramen magnum (Manjunath, 2002a;Acer et al, 2006). Most of those available studies have been made on dry skulls using linear dimensions, packing methods or occasionally radiological methods.…”