Magnetic Resonance Imaging (MRI) Protocol
Three experienced Neuroradiologists who are blinded to patients’ data
reviewed the MR images (1.5 T; Siemens, Magnetom-Avantou, Germany) of
all patients in the study, and 10 measurements other than TH were
obtained from this study. On repeated tests, high intraobserver
reliability was demonstrated (with 95 percent confidence intervals) in
20 randomly selected situations. Both the CM-I (n=100) and control
(n=100) groups were evaluated regarding the axial, sagittal and coronal
T1 and T2 weighted MRIs. The measurements were obtained manually from
the mid-sagittal images. These measurements consisted of; F1: Tonsillar
herniation; F2: Distance from the pons to FM; F3: Distance from corpus
callosum to FM; F4: Distance from Fastigium to FM; F5: Distance from the
pons to dens axis; F6: Distance from corpus callosum to dens axis; F7:
Distance from Fastigum to dens axis; F8: Distance from dorsum sella to
dens axis; F9: Clivus length; F10: Distance from dens axis to posterior
margin of FM; F11: Clivus canal angle (Weckenheim line- posterior
vertebral body line) (Figure 1).