Non-neoplastic pathology at the crossroads between neck imaging and cardiothoracic imaging

Figures

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  Fig. 1. Anatomy of the thoracic inlet. The trachea is commonly located anterior and right lateral to the esophagus. The aortic arch typically gives rise to three main branches: the brachiocephalic artery (also known as the innominate artery or brachiocephalic trunk) which divides into the right common carotid artery and right subclavian, the left common carotid artery, and the left subclavian artery. The subclavian veins join the internal jugular veins to form the brachiocephalic veins (also known as innominate veins), which empty into the superior vena cava (SVC). The brachial plexus is comprised of nerve roots from cervical level 5 to thoracic level 1 and provides motor and sensory innervation to the shoulder and arm [1]. The phrenic nerve arises from cervical levels 3–5, running along the anterior surface of the anterior scalene muscle in the neck and enter the thorax posterior to the subclavian vein, providing innervation for the diaphragm. The bilateral vagus nerves are rarely directly discernible, even with high-resolution imaging. Their location, however, may be inferred by recognizing anatomic landmarks of their expected course and should be kept in mind during interpretation…

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  Fig. 2. Infrahyoid deep neck spaces. The carotid space (CS) contains the cranial nerves IX–XII, internal jugular vein, and the internal carotid artery. The retropharyngeal space (RPS) is anterior to the vertebral column. The suprahyoid RPS contains fat and medial and lateral RPS nodes whereas the infrahyoid RPS contains fat only. The danger space (DS) is a potential space in the posterior RPS, separated from the anterior RPS by a facial “trap door”, approximately at the level of T3. RPS infection or tumor may spread to the mediastinum via this route. The visceral space (VS) contains thyroid and parathyroid glands, trachea, esophagus, recurrent laryngeal nerves, and pretracheal and paratracheal nodes. The posterior cervical space (PCS) contains fat, CNXI, and level V nodes. The perivertebral space (PVS) includes the prevertebral PVS and the paraspinal PVS. The prevertebral PVS contains brachial plexus and phrenic nerve, vertebral body, veins, arteries, and prevertebral and scalene muscles within. The paraspinal PVS contains only posterior vertebra elements and paraspinal muscles [3]

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  Fig. 3. Anatomical contents of the upper thorax

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  Fig. 4. Algorithmic approach to pathology of the thoracic inlet region

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  Fig. 5. Aberrant right subclavian artery. Axial (a) CT image demonstrating aberrant right subclavian artery (arrow) coursing posterior to the esophagus (asterisk) and trachea (triangle). b 3D model demonstrating the distal take-off the aberrant right subclavian artery (arrow) from the aortic arch

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  Fig. 6. Partial anomalous pulmonary venous return. 3D reformat (a) and axial contrast-enhanced CT (b) demonstrating right upper lobe partial anomalous pulmonary venous return (arrow) draining into the SVC. 3D reformat (c) and double oblique (d) contrast-enhanced CT demonstrating left upper lobe partial anomalous pulmonary venous return (arrow) draining to the left brachiocephalic vein

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  Fig. 7. Internal jugular vein thrombus. Coronal contrast CT image demonstrating a catheter within the right internal jugular vein and nonopacification of the vessel, findings consistent with right internal jugular vein catheter-associated thrombus

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  Fig. 8. Internal jugular vein thrombus. Grayscale ultrasound images of the same patient in Fig. 7 with (a) and without compression (b) demonstrating heterogeneous echogenic material within the jugular vein which was noncompressible (arrow), findings consistent with thrombus. Note the catheter within the vessel. c Color Doppler ultrasound image demonstrate lack of blood flow (arrows) in the internal jugular vein confirming the presence of thrombus

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  Fig. 9. Lemierre’s syndrome. Contrast-enhanced axial (a) CT image of the thoracic inlet demonstrating a filling defect (asterisk) within the left internal jugular vein consistent with acute thrombus. Contrast-enhanced coronal (b) CT image demonstrates the extensive inflammatory changes and abscesses (arrow) within the soft tissues of the left neck. Together, these findings are consistent with the findings of Lemierre’s syndrome with extension into the thoracic inlet. Axial noncontrast CT (c) images in a companion case demonstrating multiple septic emboli within the pulmonary parenchyma (arrows). Note that a large right and small left complex pleural fluid collection (asterisk) was also present in this patient

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  Fig. 10. Mediastinitis. Axial (a) and coronal (b) noncontrast CT images demonstrating inflammatory changes and soft tissue stranding (arrows) of the mediastinum secondary to mediastinitis. Note the associated diffuse thickening of the esophageal wall in this patient with suspected esophageal wall perforation

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  Fig. 11. Traction injury of the brachial plexus. Patient with acute traumatic left C7 nerve root avulsion secondary to traction injury of the brachial plexus. Axial (a) short tau inversion recover (STIR) MR images demonstrate increased signal (asterisk) of the left neck base consistent with edema of the soft tissues at the site of injury. Coronal (b) STIR MR image demonstrate a bright signal fluid collection (arrow) which communicates with the cerebral spinal fluid of the spinal cord consistent with posttraumatic pseudomeningocele. Coronal (c) STIR MR image of a companion case demonstrating diffuse increased signal (asterisk) of the left neck base and thoracic inlet consistent with edema due to brachial plexus traction injury

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  Fig. 12. Perineural (Tarlov) cyst of the brachial plexus. Axial MR STIR image demonstrates a cerebral spinal fluid intensity simple cystic structure (arrow) arising from the left C6–7 nerve root sheath consistent with a perineural (Tarlov) cyst