Abstract
Background
Anatomical variabilities in the morphometric characteristics of the tentorial notch
have been demonstrated through cadaveric studies on humans. Nevertheless, it is important
to note that the measurements may be subject to variability due to postmortem effects.
The aim of the study was to assess the morphometry of the tentorial notch in living
individuals using magnetic resonance imaging (MRI).
Methods and Materials
A retrospective cross-sectional study was conducted and 1,043 cases were analyzed
for the institutional archive from January 2021 till December 2022. Variables measured
were maximum notch width (MNW), anterior notch length, notch length (NL), interpedunculoclival
distance, and apicotectal distance using RadiAnt DiCom viewer. A quartile distribution
technique was applied to all measurements and patients were classified into different
types of tentorial notch.
Results
We studied 1,043 patients between the ages of 2 months and 84 years with normal MRI
scans. Quartile analysis was applied to all measurements. Based on the quartile group,
MNWs were classified into wide, narrow, and midrange, and NLs were classified into
long, short, and midrange. According to criteria established by Adler and Milhorat,
classification of tentorial notch was done and we found the following: short and wide
(4.2%), short and medium (12%), short and narrow (9.1%), medium and wide (12.4%),
classical (25.3%), medium and narrow (12.4%), long and wide (8%), long and medium
(12.6%), and long and narrow (4%).
Conclusion
The dimension of tentorial notch significantly varies among different age groups.
NL and MNW are significantly larger in those above 60 years of age. Typical type of
notch was the most common variety in our sample and short wide and long narrow were
least common types.
Keywords
herniation - magnetic resonance imaging - morphometry - neuroimaging - tentorial notch
