Specific Imaging Findings

Lhermitte–Duclos disease (LDD) is hypodense on CT and contains slightly hyperdense striations, referred to as “corduroy” or “tiger striping” patterns. It is relatively well-defined and has no surrounding edema. The lesion produces relatively little mass effect for its size but compression on the fourth ventricle may lead to obstructive hydrocephalus. On MRI, the mass is T1 hypointense with striations and its bulk is T2 hyperintense. The characteristic striations tend to have signal intensity similar to the gray matter. The lesions are bright on DWI but without reduced diffusion on ADC maps. Contrast enhancement is rare, has no clinical significance and usually follows the striated appearance. Susceptibility-weighted imaging (SWI) demonstrates large veins and perfusion studies may show elevated relative cerebral blood volume. On MR spectroscopy, choline is normal, creatine and myo-inositol levels are increased, n-acetyl aspartate is low, and lactate may be present.

Pertinent Clinical Information

All patients with LDD have Cowden syndrome. Other manifestations of this syndrome include: facial trichilemmomas, oral papillomatosis, palmar and plantar keratosis, gastrointestinal polyps, genitourinary malignancies, and hamartomas in the breast and thyroid gland. Most patients are male and although the disease may manifest itself at any age, Lhermitte–Duclos is generally encountered in young adults between 30 and 40 years old. Neurological symptoms may include hydrocephalus, ataxia, and brainstem findings such as multiple cranial nerve problems. The lesions grow very slowly or not at all and when indicated, surgical resection is the treatment of choice.