J Korean Radiol Soc.  2006 Jul;55(1):21-32. 10.3348/jkrs.2006.55.1.21.

Bright Intracranial Lesions on Diffusion-weighted Images: A Pictorial Review

• Choi DS

• KMID: 2103794
• DOI: http://doi.org/10.3348/jkrs.2006.55.1.21

Abstract

Diffusion-weighted imaging (DWI) is a MR sequence that is used to evaluate the rate of microscopic water diffusion within the tissues. The ability to measure the rate of water diffusion is important because this is frequently altered in various disease processes. Generally, the lesions with restricted water diffusion show bright intensity on DWI, but the lesions without restricted water diffusion can also show bright intensity on DWI, which is called the "T2 shine through effect". With DWI, we can sensitively detect hyperacute infarction (within 6 hours after symptom onset), and this is difficult to detect with using CT and the conventional MR sequences. The acute and subacute lesions of hypoxic-ischemic encephalopathy and carbon monoxide intoxication also show bright intensity on the DWI. The other diseases that can show bright intensity on the DWI include acute and subacute diffuse axonal injury lesions, hyperacute and late subacute hematomas, cerebral abscess, subdural empyema, acute herpes encephalitis, various tumors and such degenerative and demyelinating diseases as multiple sclerosis, posterior reversible encephalopathy syndrome, Wilson's disease and Wernicke's encephalopathy.

Keyword

Brain; Magnetic resonance (MR), diffusion study

MeSH Terms

Brain
Brain Abscess
Carbon Monoxide
Demyelinating Diseases
Diffuse Axonal Injury
Diffusion
Empyema, Subdural
Encephalitis, Herpes Simplex
Hematoma
Hepatolenticular Degeneration
Hypoxia-Ischemia, Brain
Infarction
Multiple Sclerosis
Posterior Leukoencephalopathy Syndrome
Water
Wernicke Encephalopathy
Carbon Monoxide
Water