title: Label-free intraoperative parathyroid localization with near-infrared autofluorescence imaging.
abstract: BACKGROUND
  The inability to accurately localize the parathyroid glands during parathyroidectomy and thyroidectomy procedures can prevent patients from achieving postoperative normocalcemia. There is a critical need for an improved intraoperative method for real-time parathyroid identification.
  
  
  OBJECTIVE
  The objective of the study was to test the accuracy of a real-time, label-free technique that uses near-infrared (NIR) autofluorescence imaging to localize the parathyroid.
  
  
  METHODS
  The study was conducted at the Vanderbilt University endocrine surgery center.
  
  
  METHODS
  Patients undergoing parathyroidectomy and/or thyroidectomy were included in this study. To validate the intrinsic fluorescence signal in parathyroid, point measurements from 110 patients were collected using NIR fluorescence spectroscopy. Fluorescence imaging was performed on 6 patients. Imaging contrast is based on a previously unreported intrinsic NIR fluorophore in the parathyroid gland. The accuracy of fluorescence imaging was analyzed in comparison with visual assessment and histological findings.
  
  
  METHODS
  The detection rate of parathyroid glands was measured.
  
  
  RESULTS
  The parathyroid glands in 100% of patients measured with fluorescence imaging were successfully detected in real time. Fluorescence images consistently showed 2.4 to 8.5 times higher emission intensity from the parathyroid than surrounding tissue. Histological validation confirmed that the high intrinsic fluorescence signal in the parathyroid gland can be used to localize the parathyroid gland regardless of disease state.
  
  
  CONCLUSIONS
  NIR fluorescence imaging represents a highly sensitive, real-time, label-free tool for parathyroid localization during surgery. The elegance and effectiveness of NIR autofluorescence imaging of the parathyroid gland makes it highly attractive for clinical application in endocrine surgery.
authors.affiliation: Biomedical Photonics Laboratory (M.A.W., C.P., A.M.-J.), Department of Biomedical Engineering Vanderbilt University, Nashville, Tennessee 37235; Murfreesboro Surgical Center (L.M.W.), Murfreesboro, Tennessee 37129; Division of Surgical Oncology (J.E.P.), Ohio State University, Columbus, Ohio 43210; Division of Surgical Oncology and Endocrine Surgery (C.C.S.), Vanderbilt University, Nashville, Tennessee 37232; and Division of Surgical Endocrinology (J.T.B.), St Thomas Midtown Hospital, Nashville, Tennessee 37203.
authors.forename: Melanie A
authors.initials: MA
authors.lastname: McWade
authors.forename: Constantine
authors.initials: C
authors.lastname: Paras
authors.forename: Lisa M
authors.initials: LM
authors.lastname: White
authors.forename: John E
authors.initials: JE
authors.lastname: Phay
authors.forename: Carmen C
authors.initials: CC
authors.lastname: Solórzano
authors.forename: James T
authors.initials: JT
authors.lastname: Broome
authors.forename: Anita
authors.initials: A
authors.lastname: Mahadevan-Jansen
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D003199:Computer Systems; D003952:Diagnostic Imaging / Q000379:methods*; D004285:Dogs; D013507:Endocrine Surgical Procedures; D005260:Female; D005453:Fluorescence; D005456:Fluorescent Dyes; D006801:Humans; D008297:Male; D008875:Middle Aged; D010279:Parathyroid Diseases / Q000473:pathology / Q000601:surgery; D010280:Parathyroid Glands / Q000033:anatomy & histology* / Q000601:surgery*; D016105:Parathyroidectomy / Q000379:methods*; D010865:Pilot Projects; D015203:Reproducibility of Results; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D013959:Thyroid Diseases / Q000473:pathology / Q000601:surgery; D013965:Thyroidectomy / Q000379:methods*
chemical_list: D005456:Fluorescent Dyes