Fig. 7
From: Easily detected signs of perineural tumour spread in head and neck cancer
Coronal contrast-enhanced T1-weighted image (a) shows marked enhancement of left pterygoid muscles (between arrows in a) indicative of acute denervation of the muscles supplied by the motoric branch of V3. On an axial T2 weighted image in a different patient (b), the denervated muscles show marked hyperintensity (arrow in b) due to oedema in the acute phase and due to fatty replacement in the chronic phase. Muscular volume loss is usually the only distinguishing feature between the two on T2-weighted images with atrophy present in the chronic phase. Muscular atrophy and fatty replacement, as reflection of chronic denervation, can also be easily identified on axial T1 sequence (arrow in c). These findings can indicate the presence of (motoric) V3 malfunction due to PNTS