title: Advanced MR imaging in Lhermitte-Duclos disease: moving closer to pathology and pathophysiology.
abstract: BACKGROUND
  Lhermitte-Duclos disease (LDD, dysplastic gangliocytoma) is an extremely rare cerebellar lesion of uncertain etiology. The debate as to whether it constitutes a neoplastic, malformative, or hamartomatous lesion is still continuing. In this report we explore the usefulness of susceptibility-weighted imaging (SWI), diffusion weighted imaging (DWI), perfusion imaging, and chemical shift imaging (CSI) in demonstrating the pathology and pathophysiology in two patients with LDD.
  
  
  METHODS
  MR imaging of the brain and the cervicodorsal spine was performed on a 1.5-T scanner in a 47-year-old woman presenting with numbness and paresthesia of both upper and lower limbs, and in a 17-year-old male with right frontal headache associated with neck pain.
  
  
  RESULTS
  Routine imaging in the first patient showed a left-side cerebellar mass with characteristic 'tiger-striped' thick folia associated with Chiari I malformation, tonsillar herniation and cervicodorsal syringomyelia and in the second patient a right cerebellar mass with similar findings. The SWI demonstrated the characteristic deep running veins between the folia, which is thought to be the cause for vascular contrast enhancement. Diffusion showed a T2 shine-through effect with mild increased diffusivity, and perfusion showed increase in relative cerebral blood volume, relative cerebral blood flow, and mean transit time in the lesion. MR spectroscopy demonstrated reduction in metabolites and a prominent lactate peak in both the patients. The pathological and pathophysiological significance of these findings is discussed.
  
  
  CONCLUSIONS
  MRI with the newer imaging capabilities can demonstrate the pathology and pathophysiology in Lhermitte-Duclos disease better. SWI helps in detecting the veins around the thickened folia.
authors.affiliation: Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India. drbejoy2002@yahoo.com
authors.forename: B
authors.initials: B
authors.lastname: Thomas
authors.forename: T
authors.initials: T
authors.lastname: Krishnamoorthy
authors.forename: V V
authors.initials: VV
authors.lastname: Radhakrishnan
authors.forename: C
authors.initials: C
authors.lastname: Kesavadas
mesh_terms: D000293:Adolescent; D002528:Cerebellar Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D005729:Ganglioneuroma / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D006223:Hamartoma Syndrome, Multiple / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged