Progression of pathological changes in the middle cerebellar peduncle
by diffusion tensor imaging correlates with lesser motor gains after pontine infarction.
However, these subtypes share common histopathological changes, characterized by neuronal loss, gliosis and the presence of glial cytoplasmic inclusions (GCI) with a-synuclein.5 In MSA-P the degenerative changes predominantly affect the basal ganglia, particularly the putamen seen as hyperintense rim at the putaminal edge, atrophy and hypointensity of putaminal body on T2WI while in MSA-C changes predominantly affect infratentorial structures like pons and cerebellum, seen as atrophy and hyperintense signals in pons, cerebellum and middle cerebellar peduncles
with pontine hyperintensity (hot cross bun sign) on axial image,4 which was seen in both of our patient's MRI.
Our case's radiological features were rather atypical and subtle; the mass was located in the right middle cerebellar peduncle
involving the superior vermis and indenting rather than filling the fourth ventricle.
Caption: Figure 4: Magnetic resonance imaging cerebellar peduncles
showing "molar tooth appearance"
Caption: Figure 1: Patients with PD had lower FA values in several anatomic locations, including the left middle cerebellar peduncle
, midbrain, forceps minor of the right frontal lobe, inferior longitudinal fasciculus of the left occipital lobe, left cingulum, left parietal WM, inferior longitudinal fasciculus of the right parietal lobe, and superior longitudinal fasciculus of the left frontal lobe.
Caption: Figure 1: Axial (a) and coronal (b) noncontrast computed tomography (CT) of the head demonstrates hemorrhage in the region of the inferior right cerebellar peduncle
, which appeared intraparenchymal, with extension into the fourth ventricle.
Fifth patient with cerebellar signs, showed abnormal high intensity in both inferior cerebellar peduncle
. Sixth patient with right arm weakness, had bilatereal subcortical white matter hyperintense signal lesions.
2), and showed T2 signal change in the brainstem, cerebellar peduncles
and cerebellum associated with variable enhancement on contrasted T1-weighted images.
(1) This appearance is a result of absence or hypoplasia of the cerebellar vermis, lack of normal dorsal decussation and consequent enlargement of the superior cerebellar peduncles
which follow a more horizontal course as they extend perpendicularly to the brainstem between the midbrain and the cerebellum.
Two patients had balance problems which were likely due to involvement of inferior cerebellar peduncles
as there was no cerebellar lesion.
Surgical resection of all or most of the tumor is possible in most cases unless it has spread to the 4th ventricle or cerebellar peduncle
. Postoperative lumbar puncture to look for tumor cells and gadolinium-enhanced MRI to look for leptomeningeal involvement (for neuroaxial drop metastasis) should be performed.
The red nucleus and the ipsilateral inferior olivary nucleus are connected via the central tegmental tract, and the dentate nucleus connects to the contralateral red nucleus through the superior cerebellar peduncle
. There are no direct connections between the inferior olivary nucleus and the contralateral dentate nucleus.