title: Quantitative assessment of the T2 relaxation time of the gluteus muscles in children with Duchenne muscular dystrophy: a comparative study before and after steroid treatment.
abstract: OBJECTIVE
  To determine the feasibility of using T2 mapping as a quantitative method to longitudinally follow the disease activity in children with Duchenne muscular dystrophy (DMD) who are treated with steroids.
  
  
  METHODS
  ELEVEN BOYS WITH DMD (AGE RANGE: 5-14 years) underwent evaluation with the clinical functional score (CFS), and conventional pelvic MRI and T2 mapping before and during steroid therapy. The gluteus muscle inflammation and fatty infiltration were evaluated on conventional MRI. The histograms and mean T2 relaxation times were obtained from the T2 maps. The CFS, the conventional MRI findings and the T2 values were compared before and during steroid therapy.
  
  
  RESULTS
  None of the patients showed interval change of their CFSs. On conventional MRI, none of the images showed muscle inflammation. During steroid treatment, two boys showed increased fatty infiltration on conventional MRI, and both had an increase of the mean T2 relaxation time (p < 0.05). The remaining nine boys had no increase in fatty infiltration. Of these, three showed an increased mean T2 relaxation time (p < 0.05), two showed no change and four showed a decreased mean T2 relaxation time (p < 0.05).
  
  
  CONCLUSIONS
  T2 mapping is a feasible technique to evaluate the longitudinal muscle changes in those children who receive steroid therapy for DMD. The differences of the mean T2 relaxation time may reflect alterations in disease activity, and even when the conventional MRI and CFS remain stable.
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA. Hee.Kim@cchmc.org
authors.forename: Hee Kyung
authors.initials: HK
authors.lastname: Kim
authors.forename: Tal
authors.initials: T
authors.lastname: Laor
authors.forename: Paul S
authors.initials: PS
authors.lastname: Horn
authors.forename: Brenda
authors.initials: B
authors.lastname: Wong
mesh_terms: D000293:Adolescent; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D002081:Buttocks; D002648:Child; D002675:Child, Preschool; D005240:Feasibility Studies; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D053580:Muscle Strength / Q000187:drug effects; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000503:physiopathology*; D020388:Muscular Dystrophy, Duchenne / Q000188:drug therapy* / Q000503:physiopathology*; D015588:Observer Variation; D011282:Pregnenediones / Q000627:therapeutic use; D011446:Prospective Studies
chemical_list: D000893:Anti-Inflammatory Agents; D011282:Pregnenediones; C021988:deflazacort
references.citation: J Magn Reson Imaging. 1994 Jan-Feb;4(1):59-64
references.pmid: 8148557
references.citation: Semin Musculoskelet Radiol. 2003 Dec;7(4):297-305
references.pmid: 14735428
references.citation: Neuromuscul Disord. 1997 Dec;7(8):482-6
references.pmid: 9447604
references.citation: Radiology. 2004 Aug;232(2):592-8
references.pmid: 15215540
references.citation: Dev Med Child Neurol. 1984 Oct;26(5):569-73
references.pmid: 6510558
references.citation: Neurology. 2005 Sep 27;65(6):826-34
references.pmid: 16093456
references.citation: Clin Radiol. 2007 Feb;62(2):160-5
references.pmid: 17207699
references.citation: Muscle Nerve. 1996 Mar;19(3):302-10
references.pmid: 8606693
references.citation: Rheumatology (Oxford). 2004 May;43(5):603-8
references.pmid: 14983103
references.citation: Arthritis Rheum. 2004 Mar;50(3):901-5
references.pmid: 15022333
references.citation: Arch Neurol. 1987 Aug;44(8):818-22
references.pmid: 3632394
references.citation: J Magn Reson Imaging. 2007 Feb;25(2):433-40
references.pmid: 17260395
references.citation: Radiology. 1993 Feb;186(2):475-80
references.pmid: 8421754
references.citation: NeuroRx. 2006 Apr;3(2):225-34
references.pmid: 16554260
references.citation: Muscle Nerve. 1983 Feb;6(2):91-103
references.pmid: 6343858
references.citation: Muscle Nerve. 1991 Aug;14(8):771-4
references.pmid: 1891001
references.citation: Neurology. 1991 May;41(5):667-72
references.pmid: 2027481
references.citation: J Neurol Neurosurg Psychiatry. 2006 Oct;77(10):1177-9
references.pmid: 16980656
references.citation: Arch Phys Med Rehabil. 1957 Sep;38(9):574-9
references.pmid: 13459572
references.citation: Neurology. 1991 May;41(5):661-6
references.pmid: 1781820
references.citation: Neuromuscul Disord. 2002 Oct;12 Suppl 1:S162-5
references.pmid: 12206811