Contrast-enhanced magnetic resonance imaging and perfusion-weighted imaging for monitoring features in severe CLIPPERS

Sir, Pittock and colleagues (2010) recently defined a new clinical–radiological inflammatory entity prominently involving the pons, which they called ‘CLIPPERS’ (Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids). The condition features the combination of a punctate and curvilinear pattern ‘peppering’ of the pons on post-contrast T1-weighted magnetic resonance images, together with an initial responsiveness to corticoid therapy. The authors of this founding paper appropriately concluded that full evaluation using non-invasive and minimally invasive procedures should be made before considering at-risk brainstem biopsy, and that clinical–radiological criteria should be sufficient to initiate treatment without pathological examination. We observed a healthy 70-year-old female presenting with gait ataxia and dysarthria in whom initial magnetic resonance work-up demonstrated punctuate and curvilinear enhancement in the pons rapidly decreasing as distance from the pons increased (Fig. 1A), though the pattern was more easily recognized on delayed follow-up examinations (Fig. 1B and C). Additional perfusion-weighted imaging was performed, which …