MR with surface coils in the follow-up after endoscopic laser resection for glottic squamous cell carcinoma: feasibility and diagnostic accuracy.

Introduction: This study focuses on the feasibility and diagnostic accuracy of MR of the larynx performed with surface coils after endoscopic laser resection (ELR) for glottic cancer.

Methods: Thirty-one MR examinations of the larynx performed with surface coils on average 12 months after ELR were retrospectively reviewed. Image quality was assessed for each acquired sequence (score 1-3). All the postoperative focal lesions detected at the excision site were analysed by assessing the following: contrast/noise ratio (CNR) normalized on lateral cricoarytenoid muscle; lesion morphology (nodular/elongated) and enhancement after contrast agent administration; apparent diffusion coefficient (ADC) on diffusion-weighted sequences (DWI).

Results: The image quality was highest for axial and coronal T2 sequences (2.39 and 2.58, respectively), and lower for the other sequences (1.66-1.72). However, in most sequences (86-100 %) the quality was considered acceptable. Among 35 focal lesions, nine were histologically proven recurrences, 26 were classified as benign focal lesions (BFL) on the basis of the subsequent follow-up. All recurrences had an intermediate T2 signal (0 < cnr0), mostly (4/5) nodular shape, intense enhancement and high ADC. The combination of T2-weighted and DWI provided the highest accuracy in the differential diagnosis between recurrences and BFL.

Conclusion: MR with surface coils is feasible and can be considered an effective tool in the follow-up after ELR for glottic cancer.