We describe acute and follow up imaging in a case of toxic leukoencephalopathy from heroin vapor inhalation treated with Coenzyme Q10.

 “Chasing the dragon” is a method of inhaling the vapors of heroin heated on a metal surface and can lead to leukoencephalopathy, which is lethal in about one quarter to one third of cases. Several series have demonstrated MRI findings suggestive of posterior predominant white matter hyperintensity and restricted diffusion which is often symmetric with possible contrast enhancement. However, there is no clear understanding of how these imaging findings progress over time and evidence is scarce; some case reports have shown a resolution of hyperintensity while others have shown persistent signal change up to one year from presentation. Several theories of pathophysiology exist; spongiform degeneration of the central nervous system white matter, with vacuolization of the oligodendroglia from direct toxicity as well as mitochondrial insult in oligodendrocytes have been posited. 

Our patient's initial restricted diffusion and hyperintensity resolved, and he developed atrophy. Furthermore, the atrophy was not posterior predominant, but rather global, with perhaps a slight frontal and temporal predominance. Further studies are needed to better characterize chronic imaging findings and the role of the pathophysiology in these findings.