Wk 1, Case 1 - Review

Patient History

A 52-year-old man with a history of hypertension and hyperlipidemia presents to the emergency department with left upper extremity weakness. The patient was last known well two days prior.

Findings

CT and CTA HEAD:

There is an ill-defined region of hypoattenuation in the right frontal and anterior temporal lobes with focal mass effect extending to involve the right corona radiata and posterior aspect of the basal ganglia. There is sulcal effacement of the right frontal and temporal lobes with mild effacement of the right lateral ventricle.

There is no acute intracranial hemorrhage or midline shift. Small foci of hypoattenuation in the anterior aspect of the left frontal lobe are likely secondary to chronic infarcts. The calvarium is unremarkable. Paranasal sinuses and mastoid air cells are clear. The orbital contents are unremarkable. Periapical lucency is noted about the right maxillary second premolar tooth.

There is nonvisualization of the petrous and posterior aspect of the cavernous segment of the right internal carotid artery. The supraclinoid and cavernous segments of the right ICA are reconstituted. The petrous, cavernous, and supraclinoid segments of the left internal carotid artery are unremarkable.

There is focal mild to moderate stenosis at the right M1 and M2 junction. The left M1 and M2 segments are unremarkable. There is mild asymmetry of the A1 segments, likely secondary to developmental change. Visualized distal branches of the anterior cerebral arteries are unremarkable.

The basilar artery and V4 segments of vertebral arteries demonstrate normal caliber. Posterior cerebral arteries, superior cerebellar arteries, and PICA are visualized bilaterally and demonstrate normal caliber.

There are no aneurysms or vascular malformations.

CTA Neck:

There is complete occlusion at the origin of the right internal carotid artery with intracranial reconstitution, likely due to retrograde flow. There is mild irregularity of the left distal common carotid and proximal internal carotid arteries, which are otherwise widely patent. The vertebral arteries are unremarkable.

The thyroid is unremarkable. Age-appropriate degenerative changes of the cervical spine are noted. There is no acute osseous abnormality. Mild secretions layer within the upper trachea. There is scarring and cylindrical bronchiectasis in the right lung apex. A diminutive right upper lobe accessory bronchus is noted.

CT Perfusion:

There is decreased blood flow in the right frontal and anterior temporal lobes. Tmax is elevated in the right frontal, parietal, and temporal lobes.

CBF<30% volume (mL): 37

Tmax>6.0s volume (mL): 139

Mismatch volume (mL): 102

Mismatch ratio: 3.8

Conclusion

1. Acute ischemic infarct involving the right frontal and anterior temporal lobes with extension to the right corona radiata and posterior aspect of the basal ganglia.

2. Perfusion deficit with core infarcts in the right frontal and anterior temporal lobes and a large penumbra, as detailed above.

3. Total occlusion of the right internal carotid artery at the origin with reconstitution of cavernous and supraclinoid segments.

4. Mild to moderate stenosis at the junction of the right M1 and M2 segments.

5. Irregular contour of the left distal common carotid and proximal internal carotid arteries, which is likely secondary to prior endarterectomy. Superimposed fibromuscular dysplasia is also included in the differential diagnosis.