MRI of the hypopharynx with provocative maneuvers

Impact of systematic dynamic maneuvers during computed tomography scan on the T classification of head and neck cancers

OBJECTIVES

To evaluate the impact of systematic dynamic maneuvers during CT scan on the T-staging of head and neck cancer (HNC).

MATERIALS AND METHODS

CT scans from the initial workup of 443 consecutive patients treated for HNC in our institution were retrospectively analyzed. CT scans were performed in both expert centers (comprehensive cancer center and university hospital) and non-expert centers. We noted whether dynamic maneuvers (DM) were performed, in 3 categories, namely: DM not done (DMND), done and inadequate (DMDI), done and adequate (DMDA). In the group with DMDA, T-stage was evaluated without and with DM. Interobserver agreement for T staging was assessed after independent double reading of CT scans with and without DM by two radiologists in a random sample.

RESULTS

Among the 443 CT scans, DMND was observed in 36.3%, DMDI in 9.3% and DMDA in 54.4%. DMDA were significantly more frequent in expert than in non-expert centers (93.4 vs 6.6%, p < 0.001). In CT scans with DMDA, analysis of the 141 scans rated as T1, T2, T3, or T4 without DM showed agreement of 88.7% with scans with DM, corresponding to a reclassification rate of 11.3% (kappa = 0.85, 95%CI [0.78;0.92]). Among lesions initially classed as Tx without DM (N = 100), the reclassification rate was 76% including DM.

CONCLUSION

The performance of systematic DM integrated into CT protocols is useful to reclassify the T stage in HNC and is essential in case of lesions initially classified as Tx without DM. DM should be performed routinely in expert and nonexpert centers.

Dynamic maneuvers in local staging of head and neck malignancies with current imaging techniques: principles and clinical applications

Imaging has been widely demonstrated to be important in local staging of head and neck malignancies as a complement to clinical examination, including endoscopy. Recent developments in multidetector row computed tomography (CT) provide better anatomic resolution within a shorter acquisition time and wider anatomic coverage. However, in many cases lesions still remain undefined. In such cases, performance of dynamic maneuvers could provide useful information about the local extent of a tumor. The usefulness of dynamic maneuvers has increased with the improvement in temporal and spatial resolution that resulted from the most recent techniques of multidetector row CT. The puffed cheek technique and the modified Valsalva maneuver allow evaluation of a lesion that was poorly demonstrated owing to apposition of mucosal surfaces. In some cases, phonation improves demonstration of small lesions of the vocal cords and allows more precise anatomic localization. The open mouth technique allows demonstration of a lesion that was previously overlooked due to dental amalgam artifacts.