Visualization of a congenital ear fistula using Cone-Beam Computed Tomography and Multidetector Computed Tomography Angiography

Introduction:

The surgery of congenital type I and II ear fistulas is a surgical challenge due to their complex course with branched fistula passages and possible middle ear involvement. Precise preoperative imaging is essential for planning the exact surgical procedure and to ensure complete excision of the pathology.

We describe a method of fistula imaging using cone beam computed tomography (CT) and multidetector CT angiography on an example of a patient with a recurrent ear fistula.

Method:

A 4-year-old girl was presented to us for revision surgery after several surgeries on the ear fistula on the right side. For radiological imaging, the preauricular fistula was first explored through the visible opening at the cavum conchae and then flushed by undiluted CT contrast medium. Thereafter, the flat detector cone beam CT was performed in the angiography (Philips Allura FD 20/15) of our clinic with a layer thickness of 0.5 mm and subsequent 3D reconstruction.

Results:

Preoperative imaging showed, in addition to the visible fistula, a ventral fistulous pouch formation of 5 mm along the auditory canal. Two further fistula ducts could be identified in the CT. Surgical removal was carried out using the additional visualization of the fistula ducts with methylene blue stain using via parotid gland approach and optical and electromyographic facial monitoring.

Conclusions:

The contrast medium-assisted flat-panel detector cone beam CT in combination with real-time angiography enables precise preoperative imaging of ear fistulas with low radiation exposure.

Publication History

Publication Date:
23 April 2019 (online)