Findings
Brain: Sagittal T1-weighted images demonstrate corpus callosum to be intact. No evidence of Chiari malformation. No abnormal pineal region masses. Pituitary gland is not enlarged. Diffusion imaging demonstrates no evidence of recent infarct. Axial FLAIR and T2 weighted images show the ventricular size, shape and configuration to be within normal limits. No evidence of vasogenic edema or mass effect. No abnormal intra-axial or extra-axial enhancing masses.
Neck:
Pre- and postcontrast CT was performed from the skull base to the thoracic inlet.
The study demonstrates a heterogeneous complex lesion that involves the left side of the neck. The sagittal and coronal T2 weighted images demonstrate a linear tract which extends from the expected location of the bony cartilages junction of the left external auditory canal that extends inferiorly into the parotid gland. The axial T2 and contrast-enhanced T1 weighted images demonstrate the linear tract to be associated with a cystic mass involving the deep lobe of the parotid gland which extends inferiorly into the left submandibular space and becomes a multicystic process with enhancing surrounding soft tissue which extends to the skin. There may be a draining skin fistula as there is an overlying skin marker.
There is diffuse mucosal thickening involving the left mastoid air cells.
Impressions
1. Findings most consistent with a type 2 first branchial anomaly that extends from the bony cartilaginous junction inferiorly of the external auditory canal through the deep lobe of the parotid gland with continued extension in the submandibular space. There are findings suggestive that this congenital anomaly is infected and is clinically associated with a skin fistula.
2. No evidence of vasogenic edema or mass effect.
3. No abnormal intra-axial or extra-axial enhancing masses.