title: Surgeon-performed intraoperative tumor localization in recurrent papillary thyroid carcinoma by ultrasound-guided intratumoral indigo carmine injection.
abstract: BACKGROUND
  Identification and removal of small, non-palpable tumors located within previous surgical scar tissue is challenging and time consuming and may be associated with increased risk in patients with recurrent papillary thyroid carcinoma (PTC). The purpose of the present study was to present our surgeon-performed technique and to evaluate the usefulness of ultrasound-guided intratumoral indigo carmine injection (US-III) for intraoperative tumor localization in patients with recurrent PTC.
  
  
  METHODS
  Sixteen patients with recurrent PTC in which tumors were <1.5 cm and not palpable were enrolled in this prospective study from January 2012 through March 2013.
  
  
  RESULTS
  The mean size of the target tumors was 0.85 cm (range 0.4-1.3 cm) on preoperative US. The average time required for the US-III procedure was 7.7 min (range 5-11 min). The mean volume of injected indigo carmine was 0.56 mL (range 0.3-1.0 mL); this injection expanded the tumors by a mean of 0.2 cm (23.5% increase compared with the initial tumor size; range 0.0-0.4 cm), increasing the mean size of the target tumors to 1.05 cm (range 0.5-1.5 cm). In 15 (93.8%) of the 16 patients, the recurrent tumors were successfully removed with the aid of US-III. No complications occurred in any of the patients as a result of the US-III or subsequent surgeries.
  
  
  CONCLUSIONS
  US-III is a safe and effective technique that can be performed by the surgeon for the intraoperative localization of small non-palpable tumors within previous scar tissue in patients with recurrent PTC.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Kyungpook National University, 807 Hogukno, Buk-gu, Taegu, 702-210, Republic of Korea, godlikeu@naver.com.
authors.forename: Dongbin
authors.initials: D
authors.lastname: Ahn
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Sohn
authors.forename: Heejin
authors.initials: H
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000601:surgery*; D002291:Carcinoma, Papillary; D002908:Chronic Disease; D004396:Coloring Agents / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007203:Indigo Carmine / Q000008:administration & dosage; D007267:Injections; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000601:surgery*; D011446:Prospective Studies; D025321:Surgery, Computer-Assisted; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D004396:Coloring Agents; D007203:Indigo Carmine