PT  - JOURNAL ARTICLE
AU  - Chun-Yan Li
AU  - Sarah Klohr
AU  - Haneen Sadick
AU  - Christel Weiss
AU  - Karl Hoermann
AU  - Stefan O. Schoenberg
AU  - Maliha Sadick
TI  - Effect of Time-of-Flight Technique on the Diagnostic Performance of <sup>18</sup>F-FDG PET/CT for Assessment of Lymph Node Metastases in Head and Neck Squamous Cell Carcinoma
AID  - 10.2967/jnmt.114.141192
DP  - 2014 Sep 01
TA  - Journal of Nuclear Medicine Technology
PG  - 181--187
VI  - 42
IP  - 3
4099  - http://tech.snmjournals.org/content/42/3/181.short
4100  - http://tech.snmjournals.org/content/42/3/181.full
SO  - J. Nucl. Med. Technol.2014 Sep 01; 42
AB  - Precise assessment of lymph node metastases is critical to the treatment outcome and overall survival of patients with head and neck squamous cell carcinoma (HNSCC). The purpose of this study was to investigate the effect of time-of-flight (TOF) technique on the diagnostic performance of 18F-FDG PET/CT for assessment of lymph node metastases in HNSCC patients. Methods: In 39 patients with an initial diagnosis of HNSCC, preoperative staging 18F-FDG PET/CT was performed to assess lymph node metastases before surgery and histologic verification. Potential lymph node metastases were evaluated and documented separately for the right and left neck in accordance with the head and neck lymph node level classification. Two experienced readers measured lesion volume and uptake for every PET-positive lymph node. Sensitivity, specificity, image quality, and the PET characterization of the lesion (benign or malignant) were compared between different reconstruction methods (TOF PET and standard high-definition PET) and matrices for both readers. Results: TOF PET significantly increased the maximal standardized uptake value (SUVmax) but had no significant effect on lesion volume. However, a higher SUVmax did not result in a significant increase in small-lesion detection. Sensitivity and image quality were slightly improved with TOF PET but not significantly so. Matrix, on the other hand, had a significant effect on detected lesion numbers, sensitivity, and image quality. Conclusion: For preoperative assessment of lymph node metastases in HNSCC, 18F-FDG PET/CT using TOF technique increases SUVmax in lesions and improves image quality but has no significant impact on small-lesion detectability.