Radiology Resident Case of the Week
Etiology/Pathophysiology
Cerebral vasculitits can be caused by a
number of disease processes including infectious, necrotizing and
collagen vascular disorders, but drug-induced angiitis is becomming
increasingly widespread. The pathophysiology of the drug-induced
arteritis has not precisely been well understood, but many people postulate that
a direct toxic injury to the vessel or hypersensitivity to the
impurities in the diluent is responsible for the intense
vasospasm seen by angiography. Coccaine and amphetamines are two
commonly reported culprits of necrotizing cerebral angiitis which can
lead to intracranial hemorrhage, ischemia and infarct, seizure and
death.
Pathology:
Miscellaneous
Imaging
The
unenhanced head CT shows areas of parenchymal hemorrhage in the left frontal lobe
and right basal ganglia, as well as intraventricular hemorrhage in the lateral ventricles (arrows). A subtle left parietal
subcortical infarct is also evident.
The MR spin echo images confirm the presence of subacute hemorrhage in the superior left frontal lobe, right basal ganglia, and lateral ventricles. Gyriform edema in the left parietal lobe is also noted, and is consistent with a watershed infarct at the junction of the anterior, middle and posterior cerebral arteries.
The AP and lateral right carotid arteriograms show regions of vessel caliber variation involving the anterior and middle cerebral arteries, most pronounced in the A1 and M1 segments respectively. The mid and distal segments demonstrate multiple regions of fusiform tapering (arrow heads). A focal dilatation in the superior distribution of the right lenticulostriate arteries (arrow) is also evident and represents a mycotic aneurysm corresponding to the right basal ganglia hematoma seen on CT and MRI.
The AP and lateral left internal carotid arteriograms show a similar pattern of involvement of the anterior circulation. In addition, there is delayed filling throughout the capillary and venous phases, and a region of hyperemic blush in the left frontoparietal region (arrow) which corresponds to the area of hemorrhagic infarct noted on CT and MRI.
The posterior circulation is also involved as demonstrated on the left vertebral arteriogram. Though the distal left vertebral artery is normal, there is abnormal mild tapering of the basilar artery. More severly affected are the proximal and mid segments of the posterior cerebral, superior cerebellar and anterior inferior cerebellar arteries. The most pronounced changes involve the the left posterior inferior cerebellar artery.
DDX
The multifocal distribution of cerebral hemorrhage,
parenchymal infarct and elevated ESR raised the possibility of
cerebral vasculitis, which was confirmed by cerebral angiograhy. The
findings in this case were classic for an arteritis but the
differential included both infectious and noninfectious causes, with
the working diagnosis being primary CNS angiitits. A brain
biopsy had been scheduled, but during the night before the procedure,
methamphetamines were discovered in the patient's possesion and the
patient admitted to coccaine and crystal methamphetamine abuse.
Periarteritis Nodosa, Takayasu Arteritis, SLE Arteritis, Infectious Vasculitis, Atherosclerosis.
Key references
ACR Code
Keywords:
Osborn, Ann. Diagnostic Neuroradiology. 1994.
Mosby. St. Louis.