title: Comparison of animal studies between interstitial magnetic resonance lymphography and radiocolloid SPECT/CT lymphoscintigraphy in the head and neck region.
abstract: OBJECTIVE
  To comparatively assess two techniques, radiocolloid SPECT/CT lymphoscintigraphy and interstitial MR lymphography using SPIO and gadoxetate disodium, in animal models.
  
  
  METHODS
  We used twenty one 8-week-old male nude mice of strain BALB/c Slc-nu/nu, weighing 23-27 g. The 4.7-T MRI equipment was used to detect the SNs. T2*WI of gradient-echo sequences was acquired sequentially up to 24 h after administering SPIO, ferucarbotran. T1WI was acquired sequentially up to 80 min after administering gadoxetate disodium. (99m)Tc-phytate SPECT/CT lymphoscintigraphy was taken at 30 min after the injection to detect the SNs using animal-dedicated whole-body SPECT/CT hybrid scanner. The injection was submucosally performed in the right tongue margin of each mouse. Reading performances concerning SN visualization and its quality on interstitial MR lymphogram and SPECT/CT lymphoscintigram were performed by 3 radiologists.
  
  
  RESULTS
  The SN intensities were 0.43 for the right, 0.61 for the left at 30 min after ferucarbotran injection, with gradual decrease in intensity, and 1.43 for the right, 1.33 for the left at 10 min after gadoxetate disodium injection with a fast decrease in intensity. The base value of 1.0 was at pre-examination. The mean numbers of lymph nodes visualized were 4.00 nodes for on SPECT/CT lymphoscintigram and 2.0 for interstitial MR lymphogram. There was a statistically significant difference in the mean scores between SPECT/CT lymphoscintigraphy and interstitial MR lymphography (two factor mixed design with repeated measures on one factor: p < 0.0002).
  
  
  CONCLUSIONS
  In our comparative study using mice, the results of radiocolloid SPECT/CT lymphoscintigraphy were superior to those of interstitial MR lymphography, while both SPIO and gadoxetate disodium have a potential of being employed for sentinel node navigation surgery by interstitial MR lymphography in the head and neck region.
authors.affiliation: Department of Radiotherapy, Keio University School of Medicine, Shinjuku, Tokyo, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Kitamura
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kosuda
authors.forename: Koji
authors.initials: K
authors.lastname: Araki
authors.forename: Masayuki
authors.initials: M
authors.lastname: Tomifuji
authors.forename: Daisuke
authors.initials: D
authors.lastname: Mizokami
authors.forename: Akihiro
authors.initials: A
authors.lastname: Shiotani
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shinmoto
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Fujii
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ichihara
mesh_terms: D000818:Animals; D003102:Colloids; D003911:Dextrans; D019786:Gadolinium DTPA; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008207:Lymphatic Metastasis; D008220:Lymphography / Q000379:methods*; D058185:Magnetite Nanoparticles; D008297:Male; D051379:Mice; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
chemical_list: D003102:Colloids; D003911:Dextrans; D058185:Magnetite Nanoparticles; C073590:gadolinium ethoxybenzyl DTPA; C065507:ferumoxides; D019786:Gadolinium DTPA