title: MR imaging findings of cervical lymphadenopathy in patients with Kikuchi disease.
abstract: OBJECTIVE
  The purpose of this study was to describe the MR imaging findings of cervical lymphadenopathy in patients with Kikuchi disease (histiocytic necrotizing lymphadenitis).
  
  
  METHODS
  Nine patients with Kikuchi disease underwent MR imaging with a 1.5 T unit including diffusion-weighted (DW) imaging and five of nine underwent gadolinium-enhanced MR imaging. MR images were reviewed for numbers, sizes, locations, focal hypointense areas on T2-weighted images, focal non-enhancing areas on gadolinium-enhanced MR images, and apparent diffusion coefficients (ADCs) of enlarged lymph nodes.
  
  
  RESULTS
  52 enlarged nodes (range, 2-11 nodes; mean, 5.8 nodes per patients) were identified. Lymphadenopathy was unilateral in 7 patients (78%) and bilateral in 2 (22%). Enlarged nodes were located at level IIA in 7 nodes, IIB in 23, III in 8, IV in 4, VA in 2, and VB in 8. Focal hypointense areas on T2-weighted images were found in 7 patients (78%) and 21 nodes (40%), and had a peripheral distribution in 19 nodes (90%) and had clear margins in 16 nodes (76%). Focal non-enhancing areas were seen in 3 patients (60%) and 6 nodes (23%). ADCs were variable (range, 0.69-1.78 [×10(-3) mm2/s]; mean, 1.01±0.28).
  
  
  CONCLUSIONS
  Cervical lymphadenopathy in Kikuchi disease showed predominantly a unilateral distribution at levels II-V. Furthermore, Kikuchi disease should be considered when T2-weighted images demonstrate hypointensity areas at the peripheries of enlarged cervical nodes, which corresponded to histopathological findings of coagulative necrosis in paracortical areas.
authors: Department of Radiology, Gifu University School of Medicine, and High-level Imaging Diagnosis Center, Gifu University Hospital, 1-1 Yanagido, Gifu 501-1194, Japan. hkato@gifu-u.ac.jp
authors: Hiroki
authors: H
authors: Kato
authors: Masayuki
authors: M
authors: Kanematsu
authors: Zenichiro
authors: Z
authors: Kato
authors: Takahide
authors: T
authors: Teramoto
authors: Naomi
authors: N
authors: Kondo
authors: Yoshinobu
authors: Y
authors: Hirose
authors: Hiroaki
authors: H
authors: Hoshi
mesh_terms: D000293:Adolescent; D002574:Cervical Vertebrae / Q000473:pathology; D002648:Child; D005260:Female; D020042:Histiocytic Necrotizing Lymphadenitis / Q000150:complications* / Q000175:diagnosis*; D006801:Humans; D008206:Lymphatic Diseases / Q000150:complications* / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity