HISTORY: Cerebral aneurysm.
TECHNIQUE:
Helical axial CT images of the head were obtained during the bolus intravenous
injection of contrast.
* Multiple reformatted images and 3-D reconstructions were performed
including MIP, MPR, and surface-rendered images. This was required for optimal
detection and characterization of vessel pathology, including the grading of
stenosis.
* In regions of densely calcified plaque, an exact measurement of luminal
stenosis can be difficult.
* The distal internal carotid artery diameter was used as the denominator
for stenosis measurement.
* Automated dose control measures were utilized.
CONTRAST: 100 cc Omnipaque 350
COMPARISON: Comparison is made with the following studies:
1. CT angiogram of the head from 3/22/21.
2. MR angiogram of the brain from 1/29/25.
3. MRI study of the brain from 1/29/25.
FINDINGS:
No aneurysm is seen. No vascular dissection is identified. No hemodynamically
significant stenosis is demonstrated.
For the CT angiogram, the findings are summarized as follows:
Anterior cerebral arteries:
* Right anterior cerebral artery: No hemodynamically significant stenosis
is seen.
* Left anterior cerebral artery: No hemodynamically significant stenosis is
seen.
Middle cerebral arteries:
* Right middle cerebral artery: No hemodynamically significant stenosis is
seen.
* Left middle cerebral artery: No hemodynamically significant stenosis is
seen.
Posterior cerebral arteries:
* Right posterior cerebral artery: No hemodynamically significant stenosis
is seen.
* Left posterior cerebral artery: No hemodynamically significant stenosis
is seen.
Circle of Willis:
* At the origin of the left posterior communicating artery, there is a 2 mm
infundibulum (Series 2, Image 122). This finding represents a normal anatomic
variant. This location correlates with the MR angiogram from 1/29/25.
Basilar artery:
* No hemodynamically significant stenosis is seen.
* The basilar artery supplied by a dominant left vertebral artery.
Distal internal carotid arteries:
* Right distal ICA: No hemodynamically significant stenosis is seen.
* Left distal ICA: No hemodynamically significant stenosis is seen.
Other:
* The ventricles and sulci are normal in size.
* In the brain parenchyma, no hemorrhage, mass effect, or abnormal
enhancement is seen. In the brainstem and cerebellum, no focal lesion is
identified. No extra-axial collection is demonstrated.
* In the right temporal region, there is a 0.5 cm extra-axial calcification
(Series 2, Image 132). This finding appears stable, favoring a benign etiology.
IMPRESSION:
1. On the CT angiogram of the brain, no aneurysm is seen.
2. No hemodynamically significant stenosis is identified.