title: Computerized tomographic anatomic relationships of the thoracic paravertebral space.
abstract: OBJECTIVE
  A wide range of insertion points lateral to the midline are recommended for paravertebral blockade. The authors hypothesized that in a given subject, using an insertion point at the tip of the transverse process has a superficial but consistent depth to the pleura. The authors also hypothesized that for a given insertion point, depths to the pleura are related directly to the patient's anthropomorphic indices.
  
  
  METHODS
  Retrospective observational study.
  
  
  METHODS
  Adult tertiary teaching hospital.
  
  
  METHODS
  Forty-two adult patients.
  The authors reviewed the computerized tomography scans of 42 adult patients and correlated patients' body mass index, weight, height, and body surface area with skin and transverse process-to-pleura depths at the level of T4, 25 mm from the midline and from the tip of the transverse process. The authors found that the depth to the pleura from the transverse process was significantly deeper at 25 mm lateral to the midline than at the tip of the transverse process (21 mm [4.2mm] v 12 mm [2.7 mm], p<0.0001), and its variability was significantly larger (p = 0.005). The authors found significant correlation between anthropomorphic indices and depths to pleura and transverse process (r>0.8, p<0.0001); however, the prediction bands around their regression lines proved too broad to be clinically useful.
  
  
  CONCLUSIONS
  The authors concluded that an insertion point at the tip of the transverse process may provide effective and safer paravertebral blockade and that depth to the pleura cannot be predicted reliably by patients' morphometric profiles.
authors.affiliation: Department of Anaesthesia, Austin Hospital, Heidelberg, Victoria, Australia. Electronic address: Drchongtan@gmail.com.
authors.forename: Chong
authors.initials: C
authors.lastname: Oon Tan
authors.forename: Christelle
authors.initials: C
authors.lastname: Botha
authors.forename: Laurence
authors.initials: L
authors.lastname: Weinberg
authors.forename: David A
authors.initials: DA
authors.lastname: Story
authors.forename: Larry
authors.initials: L
authors.lastname: McNicol
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059925:Anatomic Landmarks; D000775:Anesthesia, Spinal; D000886:Anthropometry; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods; D010994:Pleura / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012867:Skin / Q000033:anatomy & histology; D013904:Thoracic Vertebrae / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed
keywords: computerized tomography; correlation; paravertebral block; paravertebral space; pleura; pneumothorax; thoracic; transverse process