PMC4789415_01
Case  1. MRI, coronal cut in T2 sequence, showing location of mass lateral to left parotid (arrow) and exerting mass effect towards the left EAC (arrowhead).
CRIOT2016-3902974.001.jpg
PMC4789415_01_CRIOT2016-3902974.001.jpg
fig1
He underwent a temporal bone MRI with and without contrast that showed a 1-centimeter lesion projecting inferiorly into the EAC, closely associated with the superoposterior parotid gland (see Figure 1).
PMC4789415_02
(a)(1-2) Case  2. Axial CT scan of the neck with contrast demonstrating a left rim-enhancing fluid collection (arrow) centered between the left parotid gland (arrowhead) and sternocleidomastoid muscle (star), posteroinferior to the EAC. (b) Duplicated EAC (arrow) containing skin and cartilage adnexae. (c) Specimen after removal. The cartilaginous duplication of the EAC along with its tract is shown.
CRIOT2016-3902974.002.jpg
PMC4789415_02_CRIOT2016-3902974.002.jpg
fig2
A computed tomography (CT) scan of the temporal bones with contrast demonstrated a 2 x 2 cm abscess between the posterior parotid gland and the sternocleidomastoid muscle, just posteroinferior to the left EAC (Figure 2(a)). The whole tract was separate from the normal EAC and deemed to be in fact a duplicated EAC (Figures 2(b) and 2(c)).
PMC4789415_03
Case  3. (a)(1-4) Preoperative CT scans. White arrow depicts the right-sided lesion. (a)(1-2) Representative axial images revealing a well-defined right neck cyst (arrow) located posterior and deep to the parotid gland, with no clear connection to the skin. (a)(3-4) The extent of the right mandibular defect containing the cyst (arrow). (b) Identification of the tract extending deep to the facial nerve. In the inferior quadrant of the picture, a forcep is stenting the tract open as the facial nerve is being retracted. (FN: facial nerve; T: BCA tract). (c) Isolated tract after separating it from the facial nerve. A clamp is on the tract while the facial nerve is being retracted. (FN: facial nerve; T: BCA tract). (d) Tract extending medially entering the angle of the mandible. A clamp is on the tract (FN: facial nerve; M: mandible).
CRIOT2016-3902974.003.jpg
PMC4789415_03_CRIOT2016-3902974.003.jpg
fig3
The wall of the larger cyst abutted the cystic encapsulation of an interrupted molar but did not involve the tooth (Figure 3(a)). It was dissected and traced anteroinferiorly where it travelled deep to the facial nerve (Figures 3(b) and 3(c)), towards the posterior aspect of the mandibular ramus and angle (Figure 3(d)).
PMC4789415_04
Case  4. (a)(1-4) MRI with and without contrast, T1-weighted images in coronal cuts, showing tract (arrow) travelling from adjacent to left EAC superiorly, down towards left submandibular fossa, posterior to the submandibular gland, and ending at the skin inferiorly. (b) Facial nerve identified and protected during surgery. The tract is seen passing deep to the nerve (FN: facial nerve; M: mandible). (c) Specimen after removal, consistent with a duplication of the EAC, containing cartilage (separate piece dissected off main specimen after excision).
CRIOT2016-3902974.004.jpg
PMC4789415_04_CRIOT2016-3902974.004.jpg
fig4
A preoperative MRI of the neck with/without contrast revealed a cystic enhancing structure in the left submandibular region, extending posterior to the mandible and superiorly to the EAC, and measuring 1 cm in greatest diameter along its tract (Figure 4(a)(1-4)). The anterior border of the SCM and posterior digastric muscle were identified and the facial nerve was identified and followed anteriorly to the pes anserinus (Figure 4(b)). Given its close relationship to the normal EAC, a small portion of the cartilaginous EAC was removed along with the specimen (Figure 4(c)).
PMC4789415_05
Case  5. (a)(1-2) CT scan with contrast, axial cuts demonstrating a left rim-enhancing postauricular abscess (arrow) adjacent to the conchal bowl (where puncta were identified at time of surgery), causing EAC stenosis (arrowhead). (b) Modified Blair incision incorporating postauricular granulation tissue (site of prior I&D). The limb of the marked incision extending down along a neck crease was marked as a possibility but not incised during the surgery, since it was unnecessary for visualization of the digastric and SCM muscles. (c) After identifying the facial nerve, an elliptical incision was carried out around the antitragal pit and dissected down. (d) Both the gentian violet within the tract and the lacrimal probe were used throughout the case to identify the tract. After initial dissection, the ellipsed skin around the pit and the contiguous tract was passed deep to the auricle and brought out through the postauricular incision keeping the entire tract intact.
CRIOT2016-3902974.005.jpg
PMC4789415_05_CRIOT2016-3902974.005.jpg
fig5
A curvilinear incision was traced from the pretragal crease, around the lobule, then continuing postauricularly in elliptical fashion around the scar and granulation tissue (a 4 x 2 cm area) (Figure 5(b)). The dye aided in identification of the lumen (Figure 5(c)). These were kept intact and excised as one specimen (Figure 5(d)).