Angiography of primary central nervous system angiitis of childhood: conventional angiography versus magnetic resonance angiography at presentation

Abstract

Background and purpose: To systematically analyze conventional angiographic (CA) features of children with primary central nervous system angiitis (cPACNS), to compare and correlate CA and MR angiography (MRA) lesion characteristics, and to define the sensitivity and specificity of MRA with CA as a reference standard.

Methods: A retrospective, single-center cohort study of consecutive patients with cPACNS was performed. Patients with CA and MRA studies at diagnosis were included. Imaging studies were blindly reviewed by 2 neuroradiologists using a standard analysis protocol. CA and MRA studies were compared using nonparametric analysis.

Results: Of 45 patients with MRA at diagnosis, there were 25 for whom CA and MRA studies were performed within 1 month of each other. These comprised the study group. The CA distribution of lesions was multifocal (76%) and proximal (86%) (P < .05) with a trend toward unilaterality (P = .06) with anterior circulation involvement (P = .08). The sensitivity and specificity of MRA for CA abnormality was 70% and 98%, respectively. There was no significant difference between MRA and CA for lesion detection or characterization (P = .87), and the modalities showed a fair correlation (kappa = 0.4).

Conclusion: Angiographic lesions are multifocal and occur proximally and unilaterally within the anterior circulation. There is no significant difference in the ability of MRA to detect and characterize lesions when compared with CA.

Fig 1.

Representative MRA and angiographic images. Aggressive appearing lesions were those that demonstrated multiple short segment irregularity with alternating narrowing and dilation (beading) (white arrow) (A) or multiple longer segmental narrowing with normal intervening vessel (black arrowheads) (B). Aneurysms (not shown) were included in this definition. Benign appearing lesions (C) had smooth (white arrows), often solitary, tapered (white arrowhead) narrowing that could be concentric or eccentric. Incidental hypoplasia of the ipsilateral A1 is noted.

Fig 2.

Good agreement of CA (A) and (B) MRA for right ICA. Both modalities demonstrate tapered narrowing of the terminal carotid and proximal M1 and A1 (carotid terminus) with focal midM1 dilation and distal narrowing. Both modalities identify beading of the proximal A1 (black arrows).

Fig 3.

Abnormal CA (A) in the context of normal MRA (B) in a patient with a lone focal stenosis of the left PcomA. No other CA abnormality was present. MR imaging was abnormal maintaining suspicion for vasculitis despite a negative MRA.

Fig 4.

A, Occlusion of the P3 segment of the right PCA on TOF MRA (white arrowhead). Inferior temporal branches (white arrows) are slightly more prominent than on the contralateral side but B, extent of collaterals and reconstitution of the distal PCA (black arrow) best seen on CA.