title: A pilot study of video-motion analysis in endovascular surgery: development of real-time discriminatory skill metrics.
abstract: OBJECTIVE
  Accurate assessment and credentialing of physicians is essential. Objective motion analysis of guide-wire/catheter manipulation to assess proficiency during endovascular interventions remains unexplored. This study aims to assess its feasibility and its role in evaluation of technical ability.
  
  
  METHODS
  A semi-automated catheter-tracking software was developed which allows for frame-by-frame motion analysis of fluoroscopic videos and calculation 2D catheter tip path-length. 21 interventionalists (6 cardiologists, 8 interventional radiologists, 7 vascular surgeons; 14/21 had performed >500 endovascular procedures) performed an identical carotid artery stenting procedure (CAS) on a VIST simulator (Mentice, Gothenburg, Sweden). Operators were sub-divided into four categories according to CAS experience: 6 inexperienced (0 CAS-group A), 3 low-volume (1-20 CAS-group B), 5 moderate-volume (21-50 CAS-group C) and 7 high-volume (>50 CAS-group D) CAS experience. Total PL was calculated for each case and comparisons made between groups. PL was correlated with: quantitative, simulator-derived metrics and qualitative performance scores (generic and procedure-specific) derived from post-hoc video analysis by three blinded observers.
  
  
  RESULTS
  Group D used 5160.3 (inter-quartile range- IQR 4046.4-7142.9) pixels of movement, compared to 6856.7 (5914.4-8106.9) for group A (p = 0.046); 10,905.1 (7851.1-14,381.5) for group B (p = 0.017); and 9482.6 (8663.5-13,847.6) for group C (p = 0.003). Statistically significant inverse correlations were seen between total PL and qualitative performance scores (rho = -0.519 for generic (p = 0.027) rho = -0.567 for procedure-specific (p = 0.014) scores). PL did not correlate with any of the simulator-derived metrics (errors, contrast volume, total procedure and fluoroscopy times, cine-loops used).
  
  
  CONCLUSIONS
  Endovascular instrument video motion analysis is feasible and may represent a valuable tool for the objective assessment of endovascular skill.
authors: Division of Surgery, Department of Surgery and Cancer, Imperial College London, UK. alex.rolls1981@googlemail.com
authors: A E
authors: AE
authors: Rolls
authors: C V
authors: CV
authors: Riga
authors: C D
authors: CD
authors: Bicknell
authors: D V
authors: DV
authors: Stoyanov
authors: C V
authors: CV
authors: Shah
authors: I
authors: I
authors: Van Herzeele
authors: M
authors: M
authors: Hamady
authors: N J
authors: NJ
authors: Cheshire
mesh_terms: D002983:Clinical Competence; D057510:Endovascular Procedures / Q000193:education*; D005240:Feasibility Studies; D006801:Humans; D010865:Pilot Projects; D014743:Videotape Recording