Patient with a superior semicircular canal dehiscence

This is a 47-year-old male patient who presented with severe pressure-related vertigo and distorted hearing in his right ear.

A coronal temporal bone CT confirmed the presence of a dehiscence of the right superior semicircular canal (arrow), and he was offered surgical treatment though a middle fossa approach.

There are few anatomic landmarks to help guide surgery of the middle fossa floor, and the surgeon may benefit from the inspection of an interactive 3D model derived from preoperative imaging prior to undertaking surgery.

Coronal CT of the patient that was imported into CardinalSim for surgical simulation.

View of the patient’s temporal bone CT as seen in CardinalSim.  

No segmentation was needed for this dataset other than using a Hounsfield unit threshold to isolate bone.

The anatomy is turned into the surgical position, and a simulated middle fossa craniotomy is performed, exposing the dehiscent superior semicircular canal.

Simulated view of surgical procedure 

Demonstrating expected location of foramen spinosum (yellow arrow) and superior semicircular canal dehiscence (red arrow).

Video of simulated bony anatomy in the surgical position with intraoperative surgical video superimposed.

This illustrates the accuracy or the representation of surgically-meaningful landmarks, such as the foramen spinosum (with bleeding requiring bipoar cuatery), and the location of the superior semicircular canal dehiscence.