MR T1-W Sequences
Claim CME CreditPOINT OF CARE INFORMATION
This CME activity consists of the student reviewing the video of the professor reviewing the case as well as the associated DICOM image set related to the case in question.
Learning Objectives
As a result of participation in this activity, participants should be able to:
- Provide improved patient care.
- Greater knowledge of the imaging characteristics of the patient's disease.
- Understand a better approach to interpretation of studies.
Faculty Disclosure
Mehmet Albayram, MD, Ivan Davis, MD, Mariam Hanna, MD, Anthony Mancuso, MD, Ronald Quisling, MD, Dhanashree Rajderkar, MD, Priya Sharma, MD, Roberta Slater, MD and Joann Stamm, MBA have disclosed that they have no relevant financial relationships. No one else is a position to control content have any financial relationship to disclose.
CME Advisory Committee Disclosure:
Conflict of interest information for the CME Advisory Committee members can be found on the following website: https://cme.ufl.edu/disclosure/.
Continuing Medical Education Credit
Accreditation: The University of Florida College of Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.
Credit: The University of Florida College of Medicine designates this enduring material for a maximum of 0.5 AMA PRA Category 1 Credits. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
CA0589-MR T1-W Sequences
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CA0589-MR T1-W Sequences
Case ReportExam
​Purpose
Assess post contrast T1 sequences for intraluminal dural sinus thrombosis. T1-w post contrast exams, especially with multiplanar reconstruction, can discriminate enhancement in the dural sinus wall collateral from intraluminal (non enhancing) thrombus (i.e. the empty delta sign), when viewed in cross-section .
Assess post contrast T1 sequence for evidence of pial venous collaterals (typically appear serpiginous, hyperemic, drain the wrong way, the vein size changes from being larger next to the dural sinus to being larger at their inception site)
Assess the post-contrast T1 sequence for post ischemic contrast leak (i.e. venous post sichemic dysautoregulation).
Assess the post-contrast T1 sequence for unexpected exaggerated filling of atypical venous egress routes (i.e. filling into the orbits or posterior fossa veins or the nasopharyngeal venous plexus (evidence of re-routing of intracranial venous egress).
Assess for evidence of raised intracranial pressure, which includes evidence of brain swelling from venous congestion, optic hydrops/retroglobal edema, early hydrocephalus, effaced sulci, and possibly mass effects with herniation. These findings fall under the umbrella of CVT related pseudotumor.
Assess for nasopharyngeal/retropharyngeal infection/tumor with skull base extension and possible dural or cavernous sinus thrombosis.
Prior Study
There is evidence of aggressive right otomastoiditis with sigmoid plate dehiscence (coalescent otomastoiditis) producing a small volume, epidural abscess, which partiall compresses the adjacent dural sinus. Focal deformity of the sigmoid sinus is evident at the site of epidural abscess, however, the remaining lumen of the right sigmoid sinus and the internal jugular vein are patent. Intraluminal thrombus is present in the torcular herophile, the left transverse/sigmoid sinuses, extending into the high cervical left IJ.
CT perfusion: No CT perfusion is available
CTA of the neck
Thrombosis of the high cervical left internal jugular vein with collateral drainage into the other left neck veins. The right IJ is patent. No soft tissue abnormality is evident within the cervical soft tissues.
CTA of the head
Segmental thromboses in the dural sinuses, especially in the superior sagittal sinus (SSS) and in the left transverse sinus. Major veins in the opacified (non thrombosed) SSS segment are patent and exhibit re-routing patterns. Persistent impression remains adjacent to the small epidural abscess adjacent to the right sigmoid plate.
Delayed post contrast CT for analysis of the venocapillary pool
There are known multiple dural sinus thromboses that are underestimated on the delayed post contrast CT.
There is no evidence of reduced CT density within the venocapillary pool in either the cerebrum or cerebellum.
There is evidence of both optic hydrops and early hydrocephalus related to venous hypertension caused by the dural sinus egress block. It is concievable that the hydrocephalus could be in part related to meningitis associated with the right coalsecent otomasoiditis.
Findings
MR T1-W Sequence
There are intraluminal filling defects within the torcula, the initial segment of the left transverse sinus, the sigmoid sinus and high cervical jugular vein. The lateral segment of the left transverse sinus is patent. The SSS has thickened walls (secondary effect of dural wall venous collateralization). The previously seen intradural luminal filling defects are less evident possibly related to partial recanalization or intercurrent granulation tissue.
There is clear evidence of contrast within the emissary veins extending from the transverse sinus passing through the occipital calvarium into the enlarged venous plexus below the perisosteum of the calvarium in the same area. Additionally, there is increased size of the pharyngeal venous plexus related to venous egress passing through the cavernous sinuses.
The degree of ventricular enlargement is less obvious (although still present) compared to the ventricular size seen on the delayed post contrast CT. Presumably, recanalization has lowered the CSF pressure in the 4 day interval. The optic hydrops is also less evident. These finding represent a significant improvement from earlier studies.
There is a small, left vertex, incidental arachnoid cyst.
Impression
2. Persistent right otomastoiditis and epidural abscess; the size of the abscess has gotten smaller with treatment.
3. Some reduction in the degree of ventriculomegaly likely related to improved venous egress with reduction in CSF pressure.
