[en] Objective: To explore CT and MRI features of spongiform leucoencephalopathy after inhaling 'heroin' pyrolysate, and to improve the diagnostic ability of the disease. Methods: Four patients, which inhaled heroin vapor, received the CT or MRI pre- and post-contrast scanning. MR sequences included conventional SE T₁WI, T₂WI, fluid attenuation inverse recover (FLAIR), and MRS. Results: All 4 cases had similar symmetrical lesions involving the cerebellum, lateral brainstem, cerebral peduncles, posterior limbs of internal capsule, splenium of corpus callosum, medial lemniscuses, and posterior cerebral white mattes without enhancement. The lesions showed hypodense on CT and hypointense on T₁WI, hyperintense on T₂WI and FLAIR. Cerebellar lesions were more serious than cerebral one, and the parieto-occipital lesions were serious than frontal one. MRS showed that the abnormalities in the white matter were degenerative changes, not necrosis. Conclusion: CT and MRI findings of this diseases are characteristic. Combined with the history, the disease can be diagnosed