title: Ultrasound imaging in cadavers: training in imaging for regional blockade at the trunk.
abstract: OBJECTIVE
  The unique strategy of using cadaveric models for teaching ultrasound-guided blocks has been described for blocks of the upper and lower extremities. This report considers the parallels between cadaveric and live imaging relevant to scanning of the trunk. The inter-individual variation between subjects (particularly for epidural blocks) is also considered, for practicing ultrasound-guided or supported trunk and central neuraxial techniques.
  Ultrasound images using a portable machine C60 5-2 MHz curved array probe or HFL38 13-6 MHz linear array probe were obtained from scanning the trunk of a male adult cadaver, and were compared with ultrasound and magnetic resonance images from an adult male volunteer.
  
  
  METHODS
  Ultrasound imaging at the midline of the spine in the transverse/coronal plane provided an overview of the vertebral column, while scanning in a medial-to-lateral direction using longitudinal/sagittal plane sequentially localized the spinous, articular and transverse process. At the thoracic spine, further lateral longitudinal scanning will identify costal structures with the rib necks alternating with the hyperechoic ligamentous tissue of the costovertebral joints. Ultrasound imaging in the live subject in the paramedian longitudinal plane could be used at the thoracic and lumber spinal levels to capture the optimal ultrasound window of the epidural space. Imaging in the cadaver, especially when viewing the epidural space, is primarily limited by the tissue rigidity and lack of spine flexibility.
  
  
  CONCLUSIONS
  Cadavers may provide viable training options for practicing ultrasound imaging and real-time ultrasound needle guidance for nerve blocks at the trunk and epidural space. The training can be performed in a stress-free pre-clinical environment without time constraints and the potential for patient discomfort.
authors.affiliation: Department of Anesthesiology and Pain Medicine, 8-120 Clinical Sciences Building, University of Alberta, Edmonton, Alberta T6G 2G3, Canada. btsui@ualberta.ca
authors.forename: Ban
authors.initials: B
authors.lastname: Tsui
authors.forename: Derek
authors.initials: D
authors.lastname: Dillane
authors.forename: Jennifer
authors.initials: J
authors.lastname: Pillay
authors.forename: Anil
authors.initials: A
authors.lastname: Walji
mesh_terms: D000765:Anesthesia, Conduction; D000776:Anesthesiology / Q000193:education; D002102:Cadaver; D006801:Humans; D007367:Intercostal Nerves / Q000000981:diagnostic imaging*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008160:Lumbosacral Plexus / Q000000981:diagnostic imaging*; D009339:Needles; D013663:Teaching / Q000379:methods*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*; D018084:Ultrasonography, Interventional