Diploic venous system: radiological-anatomical correlation

Abstract

The diploic venous system is located between the outer and inner table of the flat bones of the skull calvaria. Despite the fact that it has been described over 200 years ago, there is little reference on the matter in anatomical and anthropological literature. It is remarkable that these channels can be confused with fractures in the radiologic evaluation of head trauma. This study describes the main anatomical variants of the diploic venous system and illustrates their topographic distribution. In order to achieve this goal, a cross sectional study was conducted utilizing a sample of human skulls (n=108), which were transilluminated by introducing a light source through the foramen magnum. In addition, lateral skull radiographs (n=64) were analyzed, as means of discriminating the topographical location of the veins. Hence, 5 different distribution patterns were discovered, as well as a sixth undetermined pattern. The probability of finding diploic veins in each region was determined, and the results were compared to the theoretical framework. As a conclusion, it can be said that the learning of these patterns and becoming familiarized with their anatomic variants is of significant importance when considering differential diagnosis of a radiolucent line on a skull which has undergone head trauma.

Keywords: diploic veins, encephalocranial trauma, fracture.