title: Minimally invasive thoracoscopic ultrasound for localization of pulmonary nodules in children.
abstract: OBJECTIVE
  Children with cancer may develop lesions in the lung that may represent metastatic disease. Thoracotomy is considered the standard approach for resection of pulmonary nodules. Recently, thoracoscopic techniques have been applied in these situations. However, nodules that are deep in the lung parenchyma may not be visible. A technique has been developed whereby minimally invasive thoracoscopic ultrasound (MITUS) may be used to guide resection of deep pulmonary nodules.
  
  
  METHODS
  We conducted a retrospective review of children undergoing MITUS at our institution. Only patients with single isolated lesions were chosen to have this diagnostic procedure performed. Patients undergo single lung ventilation. Two 5-mm ports are inserted, one for the grasper and the other for the camera. One 12-mm port is inserted for the flexible 10-mm ultrasound probe and the endoscopic stapler. The patient has CO(2) insufflation to create a 5-mm Hg pneumothorax. Twenty mL/kg of normal saline is introduced into the chest cavity for acoustic coupling. The ultrasound probe is used to isolate the nodule(s), guide resection, and check margins. The specimen is removed and placed in a removable specimen bag to reduce the chance of port site recurrence. After the lung has been inspected, irrigation is removed, and a chest tube inserted.
  
  
  RESULTS
  Eight procedures were performed on 7 patients (5 males, 2 females) with a median age of 15.2 years (range, 4-18 years). Patients had primary diagnoses of osteosarcoma (n = 4), Wilms' (n = 2), and lymphoma (n = 1). The median size of the lesions that were being isolated was 0.6 cm (range, 0.3-2.9 cm). None of the nodules removed were visible on the surface of the lung. Of the 8 procedures, 7 led to the removal of a pulmonary nodule. Of the 7 nodules isolated, 5 were removed thoracoscopically, with two requiring minithoracotomy because of anatomical limitations. The histologic evaluation on these specimens included osteosarcoma (n = 4), abscesses (n = 2), fibrosis (n = 1), and lymph node (n = 1). The median hospitalization was 2.5 days (range, 2-39 days). One patient had a prolonged hospitalization because of air leak and sepsis.
  
  
  CONCLUSIONS
  Minimally invasive thoracoscopic ultrasound is a real time imaging tool that helps isolate small pulmonary lesions that may otherwise be difficult to see intraoperatively. We would advocate this technique for those patients having video-assisted thoracoscopy to assist clarifying whether focal lesions are malignant, thereby guiding therapy.
authors.affiliation: Department of Surgery, Division of Pediatric Surgery, Emory University School of Medicine, Atlanta, GA, USA. kenneth.gow@seattlechildrens.org
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Gow
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Saad
authors.forename: Curt
authors.initials: C
authors.lastname: Koontz
authors.forename: Mark L
authors.initials: ML
authors.lastname: Wulkan
mesh_terms: D000293:Adolescent; D001859:Bone Neoplasms / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D005355:Fibrosis; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology; D008169:Lung Abscess / Q000000981:diagnostic imaging; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary*; D016399:Lymphoma, T-Cell / Q000000981:diagnostic imaging*; D008297:Male; D012516:Osteosarcoma / Q000000981:diagnostic imaging / Q000556:secondary*; D012189:Retrospective Studies; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging*; D013906:Thoracoscopy / Q000379:methods*; D013908:Thoracotomy / Q000379:methods; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional / Q000379:methods*; D009396:Wilms Tumor / Q000000981:diagnostic imaging / Q000556:secondary*