title: Functional magnetic resonance imaging using iron oxide particles in characterizing head and neck adenopathy.
abstract: OBJECTIVE
  In lymph nodes harboring metastases the reticuloendothelial system is replaced by tumor cells and does not concentrate iron particles. This study assesses the value of contrast magnetic resonance imaging (MRI) using ultrasmall superparamagnetic iron oxide particles (Combidex, Advanced Magnetics, Inc., Cambridge, MA) to characterize and stage neck nodes.
  
  
  METHODS
  Prospective analysis of neck imaging by Combidex MRI, with correlation from pathological assessment of resected lymph nodes.
  
  
  METHODS
  Nine patients underwent MRI and subsequent bilateral neck dissections (three), unilateral neck dissections (five) or fine-needle aspiration (one). Each case was evaluated for the number, location, MRI characteristics, and pathological assessment of lymph nodes.
  
  
  RESULTS
  Forty-nine separate nodal levels were evaluated with both Combidex MRI and pathological assessment. The presence of metastatic nodal involvement among 45 levels was correctly assessed by the Combidex MRI (three false-negative results, one false-positive result; sensitivity, 84%; specificity, 97%). Analysis was possible for 101 of the individual lymph nodes identified by MRI that could be correlated with individual nodes pathologically examined. Combidex MRI assessment was correct for 99 nodes (one-false positive result, one false-negative result; sensitivity, 95%, specificity, 99%). Standard MRI interpretation without Combidex identified that 12 of 18 nodes (67%) that were greater than or equal to 10 mm (greatest dimension) contained tumor, whereas 9 of 83 nodes (ll%) that were less than 10 mm contained tumor.
  
  
  CONCLUSIONS
  Combidex MRI provides functional information to characterize lymph nodes in the clinical staging of squamous cell carcinoma of the head and neck. The inability of MRI to identify small lymph nodes restricts the usefulness of this technique.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City 52242-1078, USA.
authors.forename: H T
authors.initials: HT
authors.lastname: Hoffman
authors.forename: J
authors.initials: J
authors.lastname: Quets
authors.forename: T
authors.initials: T
authors.lastname: Toshiaki
authors.forename: G F
authors.initials: GF
authors.lastname: Funk
authors.forename: T M
authors.initials: TM
authors.lastname: McCulloch
authors.forename: S M
authors.initials: SM
authors.lastname: Graham
authors.forename: R A
authors.initials: RA
authors.lastname: Robinson
authors.forename: M E
authors.initials: ME
authors.lastname: Schuster
authors.forename: W T
authors.initials: WT
authors.lastname: Yuh
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000601:surgery; D005260:Female; D005290:Ferric Compounds; D006258:Head and Neck Neoplasms / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011446:Prospective Studies; D012680:Sensitivity and Specificity
chemical_list: D005290:Ferric Compounds; C000499:ferric oxide