(16) Cervical thymic cysts are intimately associated with the
carotid sheath; they frequently splay the carotid artery and jugular vein, particularly when they involve the suprahyoid neck.
Caption: Figure 1: CT angiography of the neck with axial (a), coronal (b), and sagittal (c) sections of the heterogeneously enhanced irregular 2.4 x 2.2 x 2.2 cm mass within the right
carotid sheath. The green arrows refer to the neck mass.
All imaging protocols should contain anterior planar images from the ears through the inferior border of the heart to screen for ectopic adenomas, which can be located anywhere from the
carotid sheath to the inferior cardiac border.
Inferiorly it descends into the neck medial to the
carotid sheath. Postero superiorly it communicates with infra temporal fossa.
Exploration of the
carotid sheath to the lateral pharyngeal wall may be undertaken to fully excise any tract that may not have been identified on preoperative imaging (1).
When it occurs, the radiologist should examine the neck for the presence of a lesion along the course of the vagus nerve (cranial nerve X), which passes through the pars nervosa of the jugular foramen and along the
carotid sheath. (1)
It was flush with the anterior wall of the
carotid sheath and ascended towards the base of the skull.
In the current case, the infiltrative nature of this mass along the
carotid sheath suggested an extranodal process but revealed no additional specific findings.
Approaches: Sternocleidomastoid approach: Incision was given along anterior border of sternocleidomastoid, platysma and cervical fascia divided,
carotid sheath opened, great vessels looped proximally and distally, and repair of carotid artery, jugular vein, aero digestive tract was done accordingly.
Vascular leiomyoma of the
carotid sheath simulating a carotid body tumor.
Right sternocleidomastoid was retracted and
carotid sheath was opened.
The fistulous tract ascends along the
carotid sheath, then posterior to the common carotid artery, then superior to the superior laryngeal, hypoglossal, and vagus nerves; it finally opens into the piriform sinus.