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RT Journal Article
SR Electronic
T1 Low-Tube-Voltage 80-kVp Neck CT: Evaluation of Diagnostic Accuracy and Interobserver Agreement
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 2376
OP 2381
DO 10.3174/ajnr.A4052
VO 35
IS 12
A1 Wichmann, J.L.
A1 Kraft, J.
A1 Nöske, E.-M.
A1 Bodelle, B.
A1 Burck, I.
A1 Scholtz, J.-E.
A1 Frellesen, C.
A1 Wagenblast, J.
A1 Kerl, J.M.
A1 Bauer, R.W.
A1 Lehnert, T.
A1 Vogl, T.J.
A1 Schulz, B.
YR 2014
UL http://www.ajnr.org/content/35/12/2376.abstract
AB BACKGROUND AND PURPOSE: Low-tube-voltage acquisition has been shown to facilitate substantial dose savings for neck CT with similar image contrast compared with standard 120-kVp acquisition. However, its potential for the detection of neck pathologies is uncertain. Our aim was to evaluate the effects of low-tube-voltage 80-kV(peak) acquisitions for neck CT on diagnostic accuracy and interobserver agreement. MATERIALS AND METHODS: Three radiologists individually analyzed 80-kVp and linearly blended 120-kVp image series of 170 patients with a variety of pathologies who underwent dual-energy neck CT. Reviewers were unblinded to the clinical indication for CT but were otherwise blinded to any other data or images and were asked to state a final main diagnosis. Findings were compared with medical record charts, CT reports, and pathology results. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each observer. Interobserver agreement was evaluated by using intraclass correlation coefficients. RESULTS: Diagnoses were grouped as squamous cell carcinoma–related (n = 107, presence/absence of primary/recurrent squamous cell carcinoma), lymphoma-related (n = 40, presence/absence of primary/recurrent lymphoma), and benign (n = 23, eg, abscess). Cumulative sensitivity, specificity, positive predictive value, and negative predictive value for 80-kVp and blended 120-kVp images were 94.8%, 93.0%, 95.9%, and 91.1%, respectively. Results were also consistently high for squamous cell carcinoma–related (94.8%/95.3%, 89.1%/89.1%, 94.3%/94.4%, 90.1%/91.0%) and lymphoma-related (95.0%, 100.0%, 100.0%, 95.2%) 80-kVp/120-kVp image series. Global interobserver agreement was almost perfect (intraclass correlation coefficient, 0.82, 0.80; 95% CI, 0.76–0.74, 0.86–0.85). Calculated dose-length product was reduced by 48% with 80-kVp acquisitions compared with the standard 120-kVp scans (135.5 versus 282.2 mGy × cm). CONCLUSIONS: Low-tube-voltage 80-kVp CT of the neck provides sufficient image quality with high diagnostic accuracy in routine clinical practice and has the potential to substantially decrease radiation exposure. CTDIvolvolume CT dose indexDECTdual-energy CTDLPdose-length productICCintraclass correlation coefficientNPVnegative predictive valuePPVpositive predictive valueSCCsquamous cell carcinoma