Magnetic resonance imaging of the parotid gland using the STIR sequence

The object of this study was to determine the efficiency of the short tau inversion recovery (STIR) sequence in the assessment of salivary disease. Sixteen patients with tumours either in or adjacent to the parotid gland were imaged using a 1.5T Philips Gyroscan, with a standard head coil. T1-weighted spin-echo and STIR sequences were obtained in multiple planes and assessed independently by each of the authors. Positive fine needle aspiration cytology or histological proof of the nature of the imaged lesions was obtained for every patient. T1-weighted spin-echo images were most useful for visualizing anatomical structures and for identification of the facial nerve. All lesions were visible with T1-weighted images but were very much more conspicuous in the STIR sequences, for which a minimal lesion resolution of 6 mm was achieved. No contrast enhancement was required. It was not possible to determine the pathological nature of the lesion by scan appearance only. Our conclusion is that a combination of T1-weighted spin-echo and STIR sequences in the axial and coronal planes is the preferred protocol for salivary gland imaging.