title: Diffusion weighted imaging findings in the acute lateral medullary infarction.
abstract: OBJECTIVE
  Negative findings on diffusion-weighted imaging (DWI) does not exclude the possibility of brainstem infarction, particularly in the acute stage of medullary lesion. Our aim was to investigate the false-negative rate of DWI in patients with acute lateral medullary infarction.
  
  
  METHODS
  We applied DWI to 26 patients with a clinical diagnosis of lateral medullary infarction within 72 h of the onset. We assessed relationships between initial DWI findings and time-to-MRI (the time between onset of symptoms and initial DWI), number of clinical symptoms and signs, and final lesion volume.
  
  
  RESULTS
  There were 8 cases (31%) of false negatives in the initial DWI results. The occurrence of false-negative DWI findings decreased significantly as the time-to-MRI increased (P=0.014). However, the false-negative rate was not significantly correlated with the number of clinical symptoms and signs or the final lesion volume.
  
  
  CONCLUSIONS
  The diagnosis of lateral medullary infarction should not be ruled out on the basis of early negative DWI. To confirm the lesion, follow-up DWI or further MRI should be performed in cases with early negative DWI results.
authors.affiliation: Department of Neurology, Pundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: Min-Jung
authors.initials: MJ
authors.lastname: Seo
authors.forename: Sook Young
authors.initials: SY
authors.lastname: Roh
authors.forename: Yu-Suck
authors.initials: YS
authors.lastname: Kyun
authors.forename: Hyun-Jung
authors.initials: HJ
authors.lastname: Yu
authors.forename: Young-Kuk
authors.initials: YK
authors.lastname: Cho
references.citation: AJNR Am J Neuroradiol. 1997 Sep;18(8):1435-45
references.pmid: 9296184
references.citation: J Neuroimaging. 2003 Apr;13(2):158-61
references.pmid: 12722500
references.citation: Acta Radiol. 2004 Feb;45(1):78-84
references.pmid: 15164784
references.citation: Brain. 2003 Aug;126(Pt 8):1864-72
references.pmid: 12805095
references.citation: Arch Neurol. 1993 Jun;50(6):609-14
references.pmid: 8503798
references.citation: AJNR Am J Neuroradiol. 1999 Nov-Dec;20(10):1876-80
references.pmid: 10588112
references.citation: AJNR Am J Neuroradiol. 1998 Jun-Jul;19(6):1061-6
references.pmid: 9672012
references.citation: Rinsho Shinkeigaku. 1998 Feb;38(2):157-60
references.pmid: 9619082
references.citation: AJNR Am J Neuroradiol. 2000 Sep;21(8):1434-40
references.pmid: 11003275
references.citation: Rev Neurol. 2002 Jun 16-30;34(12):1127-9
references.pmid: 12134276
references.citation: Stroke. 1973 Jul-Aug;4(4):674-83
references.pmid: 4723697
references.citation: Rinsho Shinkeigaku. 1999 May;39(5):573-6
references.pmid: 10424153
references.citation: No To Shinkei. 2001 Nov;53(11):1021-6
references.pmid: 11761910
references.citation: AJNR Am J Neuroradiol. 1998 Feb;19(2):201-8; discussion 209
references.pmid: 9504466
references.citation: Stroke. 1984 May-Jun;15(3):417-26
references.pmid: 6729869