title: Subcutaneous tumor volume measurement in the awake, manually restrained mouse using MRI.
abstract: OBJECTIVE
  To describe a combination of techniques using the excellent volumetric capacities of magnetic resonance imaging (MRI) while avoiding anesthesia and maintaining high-throughput capability for tumor volume measurement in the awake mouse. This approach presents an alternative to calipers which, although cheap, fast, and easy to use, introduce many biases for tumor volume estimation.
  
  
  METHODS
  The murine CaNT subcutaneous xenograft model was used. A quiet and modestly T2-weighted spin-echo scan was acquired at 4.7T (TE = 15 msec, TR = 1100 msec, 0.5 mm isotropic resolution) while the awake mouse was held by hand in the magnet. This method was compared to standard MR in the anesthetized mouse and caliper measurements.
  
  
  RESULTS
  The combination of techniques used allows rapid, accurate, and reproducible measurement of subcutaneous tumor volumes in awake mice. It is less sensitive to both intra- and interoperator-derived biases and avoids confounds from the compliance of the fat and skin around the tumor, as well as from the tumor itself. Moreover, the data remain available for retrieval and scrutiny and reanalysis.
  
  
  CONCLUSIONS
  Rapid, accurate, and precise tumor volumetry can be performed in the awake mouse by handheld positioned MR.
authors.affiliation: CRUK/MRC Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, OX3-7DQ, Oxford, UK. Veerle.Kersemans@oncology.ox.ac.uk
authors.forename: Veerle
authors.initials: V
authors.lastname: Kersemans
authors.forename: Bart
authors.initials: B
authors.lastname: Cornelissen
authors.forename: Philip D
authors.initials: PD
authors.lastname: Allen
authors.forename: John S
authors.initials: JS
authors.lastname: Beech
authors.forename: Sean C
authors.initials: SC
authors.lastname: Smart
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000503:physiopathology / Q000662:veterinary*; D000818:Animals; D045744:Cell Line, Tumor; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000662:veterinary*; D051379:Mice; D056888:Patient Positioning / Q000662:veterinary*; D015203:Reproducibility of Results; D012149:Restraint, Physical / Q000662:veterinary*; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000473:pathology* / Q000662:veterinary*; D047368:Tumor Burden; D014851:Wakefulness