title: T2 hypointense rims and ring-enhancing lesions in MS.
abstract: BACKGROUND
  Hypointense rims peripherally on T2-weighted MRI (rim lesions) have been associated with gadolinium ring-enhancing lesions in multiple sclerosis (MS) in pathological studies. However, little is known about their frequency, we analyzed clinical significance in a cohort of MS sufferers according to routine clinical practice.
  
  
  METHODS
  We retrospectively reviewed all available MRI scans performed on our MS patients between 2000 and 2009. A total of 580 MRI scans from 257 patients were analyzed. The presence of rim lesions and ring enhancement was assessed and counted blind. Furthermore, the correlation between both patterns, and with clinical characteristics, was evaluated.
  
  
  RESULTS
  Thirty-five rim lesions were identified and 9% (24/257) of the patients showed at least one of these lesions. Forty ring-enhancing lesions were counted and 12% (29/245) of the patients who had undergone gadolinium MRI presented at least one such lesion. Thirteen lesions co-localized both patterns (40% of the rim lesions and 33% of the ring-enhancing lesions). Rim lesions and ring-enhancing lesions were observed in patients with clinically isolated syndrome (7%, 7%), relapsing-remitting (11%, 15%) and secondary progressive (13%, 9%) but none with primary progressive MS. Presence of ring-enhancing lesions was significantly associated with a shorter time to reach EDSS (Expanded Disability Status Scale) 4.0 and 6.0 (hazard ratio 7.6, 95% confidence interval 2.3-24.6).
  
  
  CONCLUSIONS
  Rim lesions and ring-enhancing lesions are present in close to 10% of patients with MS, and frequently both lesions appear independently one to the other. The association of ring enhancement with worst prognosis needs to be confirmed in prospective studies.
authors.affiliation: Service of Neurology, Hospital Clinic, Universitat de Barcelona, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Llufriu
authors.forename: Teresa
authors.initials: T
authors.lastname: Pujol
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Blanco
authors.forename: Karolina
authors.initials: K
authors.lastname: Hankiewicz
authors.forename: Mattia
authors.initials: M
authors.lastname: Squarcia
authors.forename: Joan
authors.initials: J
authors.lastname: Berenguer
authors.forename: Pablo
authors.initials: P
authors.lastname: Villoslada
authors.forename: Francesc
authors.initials: F
authors.lastname: Graus
authors.forename: Albert
authors.initials: A
authors.lastname: Saiz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019786:Gadolinium DTPA