title: A small animal holding fixture system with positional reproducibility for longitudinal multimodal imaging.
abstract: This study presents a combined small animal holding fixture system, termed a 'bridge capsule', which provides for small animal re-fixation with positional reproducibility. This system comprises separate holding fixtures for the head and lower body and a connecting part to a gas anesthesia system. A mouse is fixed in place by the combination of a head fixture with a movable part made from polyacetal resin, a lower body fixture made from vinyl-silicone and a holder for the legs and tail. For re-fixation, a similar posture could be maintained by the same holding fixtures and a constant distance between the head and lower body fixtures is maintained. Artifacts caused by the bridge capsule system were not observed on magnetic resonance (MRI) and positron emission tomography (PET) images. The average position differences of the spinal column and the iliac body before and after re-fixation for the same modality were approximately 1.1 mm. The difference between the MRI and PET images was approximately 1.8 mm for the lower body fixture after image registration using fiducial markers. This system would be useful for longitudinal, repeated and multimodal imaging experiments requiring similar animal postures.
authors.affiliation: Molecular Imaging Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kokuryo
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kimura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Obata
authors.forename: Taiga
authors.initials: T
authors.lastname: Yamaya
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kawamura
authors.forename: Ming-Rong
authors.initials: MR
authors.lastname: Zhang
authors.forename: Iwao
authors.initials: I
authors.lastname: Kanno
authors.forename: Ichio
authors.initials: I
authors.lastname: Aoki
mesh_terms: D000776:Anesthesiology / Q000295:instrumentation; D000818:Animals; D016477:Artifacts; D004867:Equipment Design; D005260:Female; D006257:Head / Q000000981:diagnostic imaging; D006614:Hindlimb / Q000000981:diagnostic imaging; D007085:Ilium / Q000000981:diagnostic imaging; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009038:Motion; D056888:Patient Positioning / Q000295:instrumentation*; D049268:Positron-Emission Tomography / Q000295:instrumentation*; D011859:Radiography; D015203:Reproducibility of Results; D012984:Software; D013131:Spine / Q000000981:diagnostic imaging; D013623:Tail / Q000000981:diagnostic imaging