title: Metastatic adenopathy from nasopharyngeal carcinoma: successful response to radiation therapy assessed by color duplex sonography.
abstract: OBJECTIVE
  Although the role of gray-scale sonography for neck nodes is well documented, it plays a limited role in the evaluation of nodal response to treatment. This preliminary limited study sought to determine color duplex sonographic changes in successfully treated metastatic nodes from nasopharyngeal carcinoma.
  
  
  METHODS
  Fourteen patients with nodal metastases from nasopharyngeal carcinoma were studied. A pretreatment sonogram was obtained for all patients. Patients were divided into two groups of seven: in one group, repeat sonograms were obtained 8 weeks after completion of treatment; in the second group, sonograms were obtained 16 weeks after treatment. The features studied included distribution of intranodal vascularity, resistive and pulsatility indexes, and peak systolic velocity. In 11 patients, follow-up sonograms were obtained 1 year after treatment.
  
  
  RESULTS
  The majority (90%) of malignant nodes from nasopharyngeal carcinoma have an increased central and peripheral vascularity, a high resistive index (0.8), and a high pulsatility index (1.8). After radiation therapy to the nodes, a reduction in intranodal vascularity and a statistically significant reduction in the resistive index (0.58 to 0.59) and pulsatility index (0.91 to 0.93) are found. Although a similar reduction in the peak systolic velocity is observed, it is not statistically significant.
  
  
  CONCLUSIONS
  Our preliminary findings suggest that after radiation therapy for malignant nodes in nasopharyngeal carcinoma, a reduction in intranodal vascularity is found, and the resistive and pulsatility indexes may return to benign parameters as early as 8 weeks after completion of treatment.
authors.affiliation: Department of Diagnostic Radiology, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, N.T., Hong Kong.
authors.forename: A T
authors.initials: AT
authors.lastname: Ahuja
authors.forename: S S
authors.initials: SS
authors.lastname: Ho
authors.forename: S F
authors.initials: SF
authors.lastname: Leung
authors.forename: J
authors.initials: J
authors.lastname: Kew
authors.forename: C
authors.initials: C
authors.lastname: Metreweli
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000556:secondary*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000473:pathology* / Q000532:radiotherapy; D009333:Neck; D011446:Prospective Studies; D018615:Ultrasonography, Doppler, Color