Skull Base Dural Thickness and Relationship to Demographic Features: A Postmortem Study and Literature Review

Abstract

Dural membrane is an important anatomic structure that surrounds and protects the entire central nervous system. Physical properties of the dura have many pathophysiological and therapeutic implications in cranial surgery, especially skull base disorders. The aim of this study is to investigate variation in skull base dural thickness and correlation with different demographic parameters. At the time of autopsy, the petrous apex dura with the underlying bone of 20 cadavers was harvested. Dural thickness was independently measured by two pathologists at the thinnest and thickest segments in the specimen. Correlational analyses were then performed to compare dural thickness with gender, age, neck circumference, height, weight, and body mass index (BMI). Mean, minimum, and maximum skull base dural thickness in our study was 0.36, 0.27, and 0.46 mm, respectively. Age demonstrated a negative correlation with dural thickness with significantly thinner dura in the older subjects, p = 0.01. There was a trend toward thinner dura in females that approached statistical significance, p = 0.06. No strong correlation could be found with body weight, height, neck circumference, or BMI. Our findings show a considerable intersubject and intrasubject variability in skull base dural thickness. Some demographic parameters also seem to impact dural thickness. Additional histological studies are needed for better understanding of the pathophysiological mechanisms pertaining to the tensile properties of the dural membrane.