eRadiograph Volume 7: Imaging of Oral Cavity | Page 304

Introduction and Anatomy This is a space lying deep in the neck surrounding the vertebral column extending from the skull base to mediastinum. This space is enveloped by the deep cervical fascia which separates it from the retropharyngeal space which is anterior to the perivertebral space. This space consists of two components the perivertebral space and the paraspinal space. Content The perivertebral space is mainly composed of muscles. The longus capitis and longus colli muscles as well as the scalene muscles. The scalene muscles are important for neck flexion, lateral bending and inspiration. Many nerves traverse this space – the phrenic nerve is seen in the prevertebral space from C3 – C5, the dorsal scapular nerve and the middle scalene muscle .The brachial plexus also traverses this space. Paraspinal Space The bulk is occupied by muscles. Splenis capitis, semisplenalis capitis, longissmus capitis are the major extensors of the head and neck. The semi spinalis capitis, long issmus capitis lies deep to the splenis capitus. Longus Colli Tendinitis This occurs due to rupture of calcium Hydroxy apatite deposits within longus Colli tendon resulting in an inflammatory response – patients present with acute neck pain. On imaging there is calcification in the longus capitus – colli tendinous insertions usually at the C1/C2 level. There is associated oedema in the retropharyngeal space. There is no enhancement, though the muscles may appear to be bulky in size. Tumors of Osseous Origin Metastatic Disease Sclerotic areas are seen in prostate, bladder and carcinoid tumors. 304 Perivertebral Space Lemierre Syndrome In this syndrome there is an acute oropharyngeal infection with secondary septic thrombophlebitis in the internal jugular vein. Nearly always this is caused by fusobacterium the infection starts as a pharyngitis and then spreads to the parapharyngeal space, RPS, PVS There is thrombosis of the internal jugular vein. The infection then spreads by the venous system to the rest of the body. The typical clinical triad is pain, a tender swollen neck (due to IJV thrombosis) non cavitatory pulmonary infiltrates due to metastatic septic thrombophlebitis on imaging there is evidence of tonsillar/peritonsillar oedema, inflammation, abscess, IJV thrombosis septic metastases elsewhere.