title: MRI findings are often missed in the diagnosis of Creutzfeldt-Jakob disease.
abstract: BACKGROUND
  Establishing a confident clinical diagnosis before an advanced stage of illness can be difficult in Creutzfeldt-Jakob disease (CJD) but unlike common causes of dementia, prion diseases can often be diagnosed by identifying characteristic MRI signal changes. However, it is not known how often CJD-associated MRI changes are identified at the initial imaging report, whether the most sensitive sequences are used, and what impact MRI-diagnosis has on prompt referral to clinical trial-like studies.
  
  
  METHODS
  We reviewed the MRI scans of 103 patients with CJD referred to the National Prion Clinic since 2007 and reviewed the presence of CJD-associated changes, compared these findings with the formal report from the referring centre and reviewed the types of sequence performed.
  
  
  RESULTS
  In sCJD we found CJD-associated MRI changes in 83 of 91 cases (91% sensitivity). However, the referring centres documented CJD-associated MRI changes in 43 of the sCJD cases (47% sensitivity). The most common region not documented by referring centres was the cortex (23 of 68 sCJD cases), but there was a statistically significant discrepancy in all regions (p<0.0001). Patients in whom MRI abnormalities were missed by the referring hospital were more advanced at the time of recruitment to a clinical trial-like study (p=0.03).
  
  
  CONCLUSIONS
  CJD-associated MRI changes are often not documented on the formal investigation report at the referring centre. This is important as delay makes enrolment to clinical trials futile because of highly advanced disease. If a diagnosis of CJD is suspected, even if the initial imaging is reported as normal, a specialist MRI review either by an experienced neuroradiologist or by a prion disease specialist unit could facilitate earlier diagnosis.
authors.affiliation: MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, and National Prion Clinic, University College London Hospitals NHS Trust, WC1N 3BG, London, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Carswell
authors.forename: Andrew
authors.initials: A
authors.lastname: Thompson
authors.forename: Ana
authors.initials: A
authors.lastname: Lukic
authors.forename: John
authors.initials: J
authors.lastname: Stevens
authors.forename: Peter
authors.initials: P
authors.lastname: Rudge
authors.forename: Simon
authors.initials: S
authors.lastname: Mead
authors.forename: John
authors.initials: J
authors.lastname: Collinge
authors.forename: Harpreet
authors.initials: H
authors.lastname: Hyare
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology*; D007562:Creutzfeldt-Jakob Syndrome / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity