title: Value of a Lower-Limb Immobilization Device for Optimization of SPECT/CT Image Fusion.
abstract: The foot and the ankle are small structures commonly affected by disorders, and their complex anatomy represents a significant diagnostic challenge. By providing information on anatomic and bone structure that cannot be obtained from functional imaging, SPECT/CT image fusion can be particularly useful in increasing diagnostic certainty about bone pathology. However, because of the lengthy duration of a SPECT acquisition, a patient's involuntary movements may lead to misalignment between SPECT and CT images. Patient motion can be reduced using a dedicated patient support. We designed an ankle- and foot-immobilizing device and measured its efficacy at improving image fusion.
  
  
  METHODS
  We enrolled 20 patients who underwent SPECT/CT of the ankle and foot with and without a foot support. The misalignment between SPECT and CT images was computed by manually measuring 14 fiducial markers chosen among anatomic landmarks also visible on bone scintigraphy. ANOVA was performed for statistical analysis.
  
  
  RESULTS
  The absolute average difference without and with support was 5.1 ± 5.2 mm (mean ± SD) and 3.1 ± 2.7 mm, respectively, which is significant (P < 0.001).
  
  
  CONCLUSIONS
  The introduction of the foot support significantly decreased misalignment between SPECT and CT images, which may have a positive clinical influence in the precise localization of foot and ankle pathology.
authors: Haute École de Santé Vaud-Filière TRM, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland.
authors: Joana do Mar F
authors: Jdo M
authors: Machado
authors: Nuclear Medicine Department, Lausanne University Hospital, Lausanne, Switzerland; and.
authors: Marina S
authors: MS
authors: Monteiro
authors: Nuclear Medicine Department, Lausanne University Hospital, Lausanne, Switzerland; and.
authors: Victor Fernandes
authors: VF
authors: Vieira
authors: Nuclear Medicine Department, Lausanne University Hospital, Lausanne, Switzerland; and.
authors: Jean-Aybert
authors: JA
authors: Collinot
authors: Nuclear Medicine Department, Lausanne University Hospital, Lausanne, Switzerland; and.
authors: John O
authors: JO
authors: Prior
authors: Área Científica de Medicina Nuclear, Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Lisbon, Portugal.
authors: Lina
authors: L
authors: Vieira
authors: Haute École de Santé Vaud-Filière TRM, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland jose.jorge@hesav.ch.
authors: José A
authors: JA
authors: Pires-Jorge
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005528:Foot / Q000000981:diagnostic imaging* / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007103:Immobilization / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D009068:Movement; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: SPECT/CT; lower limb; misalignment; patient motion