Page 107 - The Vasculitides Volumes 2

Childhood Vasculitic Stroke 83

Figure 2. Focal cerebral arteriopathy and AIS in a 15-year-old boy with acute right hemiplegia and
hemianesthesia. (A) Diffusion MRI on day 1 shows faint restricted diffusion limited to the posterior putamen
and internal capsule. (B) MRA shows reduced ICA and MCA flow with irregular narrowing of left MCA
(arrow). (C) Repeat diffusion MRI on day 11 shows new restricted diffusion extending throughout the corona
radiata and small cortical areas within the MCA and ACA territories (arrows). (D) Conventional angiography
(left ICA injection) demonstrates severe irregularity of the distal ICA and proximal MCA with alternating
“bands” of narrowing. The ACA is now occluded.

Small Vessel Type
Primary vasculitis of the small cerebral blood vessels is better defined than those

described above, involving large vessels. Unlike large vessel disease, definitive evidence of
vessel wall inflammation is often obtained by brain biopsy, allowing pathological
confirmation of vasculitis [15, 48]. Patients may present with focal symptoms but are more
likely to develop subacute, non-localizing neurological complaints such as headache,
behavioral changes, seizures, school failure or cognitive decline [13-15]. Strokes, when they
occur, do not conform to large vessel territories and ischemic lesions can be highly variable in
character and distribution [15, 48]. Hemorrhagic lesions may also occur although the
incidence is probably <10% [49]. Neuroimaging is far less specific compared to the large
vessel diseases described above. Non-invasive arterial imaging employing computed
tomography angiography (CTA) and magnetic resonance angiography (MRA) is typically
normal while parenchymal MRI can range from normal to diffusely abnormal with a wide
array of lesion characteristics [15]. Conventional angiography is also often negative and small
vessel cPACNS may also be referred to as angiography-negative vasculitis [14, 15, 43, 50].
Diagnostic criteria proposed by Calabrese and colleagues [46] for adult PACNS have been

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