Wk 2, Case 4 - Review

Patient History
Unusual uncomplicated headaches. Chiari malformation with suboccipital craniotomy and decompression.

Brain MRI from March 19, 2016:

Note is made of a suboccipital decompression procedure for Chiari malformation but there is continued distortion of the cervicomedullary
junction, pons, mid brain, and cerebellum suggesting incomplete decompression. The C1 posterior arch appears to have been removed.

Diffusion weighted scans show no evidence of an acute infarction. There is no evidence of hydrocephalus. There is distorted appearance to the
pons and midbrain with elongation. There is soft tissue to the left of the pons extending to the cerebellopontine angle cistern and the internal
auditory canal level. This tissue appears to emanate from the temporal lobes more so on the left side but there is also herniation of hippocampal tissue on the right side into the peripontine cisterns extending to the midbrain level.

The pituitary gland is prominent with upward curvature. It measures 8.6 cm in superior-inferior height and abuts on the optic chiasm. The gland
enhances homogeneously.

Tiny right lateral extra-axial fluid collections are present measuring less than 2 mm on the postcontrast FLAIR scan.

CSF pulsation studies show abnormal pulsatility at the foramen magnum.

There is prominent enhancement in the walls of the internal auditory canal. The tissue in the cerebellopontine angle cistern does not show
contrast enhancement. There is prominent enhancement of the venous system and the choroid plexus.

Since the previous examination from January 24, 2009 there has been significant crowding at the foramen magnum depression of brainstem and
cerebellar structures through a narrowed cervicomedullary junction and foramen magnum. The soft tissue around the left side of the pons was not present previously and likely represents herniating bilateral mesial temporal lobes.

Impressions
Brain images showing evidence of intracranial hypotension with herniation of mesial temporal lobes around the tentorium into the cisterns around
the brainstem, left greater than right. Ancillary findings of enlarged pituitary gland, depression of the brainstem, and tonsillar herniation through the foramen magnum with bilateral small extra-axial hygromas.

Abnormal signal in the spinal cord extending initially to the T1 level on March 31, 2016 and to the T3-T4 level on April 21, 2016. This may be from
expanding syrinx but the possibility of myelitis must be considered. Cystic change in the spinal cord at the cervicomedullary junction seen at
C2-C3 level.

Large perineural cyst at the T11-T12 neural foramen on the left side which was also evident on post myelogram CT scan from May 26, 2010. Fluid
appears to track a low this at the T12-L1 level where there may have been surgery on the left side.

Cervical spine MRI from March 31, 2016:

There is abnormal signal intensity in the cervical spinal cord extending to the thoracic region at T1-T2. The cerebellar tonsils extend below the level of the foramen magnum and there has been a suboccipital decompression procedure. Nonetheless there appears to be crowding at the foramen magnum with distortion of the appearance of the pons, midbrain, cerebellar tonsils. The cerebellar tonsil signal intensity is also abnormal and there is abnormal tissue extending on the left side of the
midbrain and pons at the level of the cerebellopontine angle cistern and internal auditory canal.

Although the abnormal signal in the cervical spinal cord ends at the T1 level on this MRI from March 31, 2016 and appears to extend further into the thoracic spine with extension to T3-T4 on the followup April 21, 2016 study. There is cystic change at the cervicomedullary junction seen best on series 4 image 8 with myelomalacia.

Incidental note is made of enlargement of the thyroid gland with multiple nodules.

Impressions
Brain images showing evidence of intracranial hypotension with herniation of mesial temporal lobes around the tentorium into the cisterns around
the brainstem, left greater than right. Ancillary findings of enlarged pituitary gland, depression of the brainstem, and tonsillar herniation through the foramen magnum with bilateral small extra-axial hygromas.

Abnormal signal in the spinal cord extending initially to the T1 level on March 31, 2016 and to the T3-T4 level on April 21, 2016. This may be from
expanding syrinx but the possibility of myelitis must be considered. Cystic change in the spinal cord at the cervicomedullary junction seen at
C2-C3 level.

Large perineural cyst at the T11-T12 neural foramen on the left side which was also evident on post myelogram CT scan from May 26, 2010. Fluid
appears to track a low this at the T12-L1 level where there may have been surgery on the left side.

Patient History
Unusual uncomplicated headaches. Chiari malformation with suboccipital craniotomy and decompression.

Findings
Thoracic spine:

Cervical spinal cord signal abnormality extends into the thoracic spine with cord enlargement. The abnormal signal ends at approximately the
T3-T4 disc level.

Axial scans through the thoracic spine show an enlarged nerve root sleeve cyst measuring approximately 1.3 cm in AP diameter with neural foraminal expansion at the T11-T12 level on the left side. No other enlarged perineural cysts are present.

There is abnormal signal intensity in the posterior left paraspinal tissues at the T12 level behind the left lamina. The left lamina may not be completely intact. This is best seen on series 9 image 28.

Impressions
Brain images showing evidence of intracranial hypotension with herniation of mesial temporal lobes around the tentorium into the cisterns around
the brainstem, left greater than right. Ancillary findings of enlarged pituitary gland, depression of the brainstem, and tonsillar herniation through the foramen magnum with bilateral small extra-axial hygromas.

Abnormal signal in the spinal cord extending initially to the T1 level on March 31, 2016 and to the T3-T4 level on April 21, 2016. This may be from
expanding syrinx but the possibility of myelitis must be considered. Cystic change in the spinal cord at the cervicomedullary junction seen at
C2-C3 level.

Large perineural cyst at the T11-T12 neural foramen on the left side which was also evident on post myelogram CT scan from May 26, 2010. Fluid
appears to track a low this at the T12-L1 level where there may have been surgery on the left side.