Vigabatrin‐associated reversible <scp>MRI</scp> signal changes

Infantile epileptic spasms syndrome (IESS) is a type of epileptic encephalopathy characterized by epileptic spasms, often associated with developmental delay and an EEG showing hypsarrhythmia.1 First-line therapy includes ACTH, high-dose prednisolone, or vigabatrin.2 Vigabatrin-associated reversible MRI signal changes are best detected by diffusion-weighted imaging and may affect the globi pallidi, thalami, brainstem, and dentate nuclei3, 4 (Figure 1). Such findings have been described in nearly 20% of the patients taking vigabatrin for IESS.3 Although its underlying pathophysiology remains unclear, infants younger than 12 months and those receiving higher doses appear to be at greatest risk.4 These MRI changes are usually asymptomatic; however, some patients may present with encephalopathy, movement disorders, or respiratory depression. A potential risk factor for symptomatic presentation is the co-administration of vigabatrin with hormonal therapy (ACTH or prednisolone).5 Notably, these abnormalities are reversible and resolve during or after vigabatrin treatment,2, 3, 6 and there is no evidence supporting permanent cerebral injury or requirement to discontinue vigabatrin. Although the correlation of vigabatrin with transient MRI abnormalities in infants with IESS is well documented, a definitive causal link has not been stablished.5 Recognizing this entity is essential to avoid unnecessary concern or intervention. The authors have nothing to disclose. None. Not required. The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions. Answers. Educational_slides. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. Vigabatrin-associated reversible MRI signal changes are best detected by which MRI sequence? Vigabatrin-associated reversible MRI signal changes affect all the structures below, EXCEPT: Answers may be found in the supporting information