title: Detection of Peripheral Arterial Disease Within the Foot Using Vascular  Optical Tomographic Imaging: A Clinical Pilot Study.
abstract: OBJECTIVE
  Vascular optical tomographic imaging (VOTI) is a novel imaging modality that is capable of detecting hemoglobin concentrations in tissue. VOTI is non-invasive, non-ionizing and does not require contrast injection. This technology was applied to the diagnosis of peripheral arterial disease (PAD) within lower extremities of diabetic patients with calcified arteries. This could be of substantial benefit as these patients suffer from comorbidities such as arterial incompressibility, which complicates diagnosis and monitoring.
  
  
  METHODS
  Forty individuals (10 non-diabetic patients with PAD, 10 diabetic patients with PAD, and 20 healthy volunteers) were enrolled in a diagnostic pilot study using the VOTI system. The patients were imaged during at high pressure cuff occlusion.
  
  
  RESULTS
  The VOTI system was capable of quantifying the blood volume changes within the foot during the thigh cuff occlusion and outputting diagnostic parameters, such as change in hemoglobin concentration, enabling the assessment of foot perfusion. This study resulted in a statistically significant difference between the healthy cohort and both the non-diabetic and the diabetic PAD cohorts (p = .006, p = .006). Receiver operating characteristic (ROC) curve analysis showed that PAD diagnosis could be made with over 80% sensitivity or specificity depending on the characteristic cutoff point. In addition, VOTI was capable of providing the locations of under-perfused regions within the foot and evaluating the severity of arterial disease, even within diabetic patients with calcified arteries, who are traditionally difficult to diagnose.
  
  
  CONCLUSIONS
  VOTI can effectively diagnose PAD independently of arterial compressibility, making it very useful for assessing vascular disease in diabetic patients.
authors.forename: M A
authors.initials: MA
authors.lastname: Khalil
authors.forename: H K
authors.initials: HK
authors.lastname: Kim
authors.forename: J W
authors.initials: JW
authors.lastname: Hoi
authors.forename: I
authors.initials: I
authors.lastname: Kim
authors.forename: R
authors.initials: R
authors.lastname: Dayal
authors.forename: G
authors.initials: G
authors.lastname: Shrikhande
authors.forename: A H
authors.initials: AH
authors.lastname: Hielscher
mesh_terms: D000368:Aged; D000465:Algorithms; D055109:Ankle Brachial Index; D017719:Diabetic Foot / Q000175:diagnosis* / Q000503:physiopathology; D004867:Equipment Design; D005260:Female; D005528:Foot / Q000098:blood supply; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008297:Male; D058729:Peripheral Arterial Disease / Q000175:diagnosis* / Q000503:physiopathology; D010865:Pilot Projects; D012372:ROC Curve; D012680:Sensitivity and Specificity; D041622:Tomography, Optical / Q000295:instrumentation / Q000379:methods*
chemical_list: D006454:Hemoglobins