OCT Imaging Complements CT in Visualizing Normal and Pathological Ears

Clinical Question

How does the capability of middle ear optical coherence tomography (OCT) imaging compare with computed tomography (CT) imaging in normal and pathological ears?

Bottom Line

Although OCT was not capable of replacing CT due to its limited field of view (FOV) and inability to image through thick bony tissues, it visualized signs of pathology that are difficult to visualize with CT, suggesting its usefulness for some middle ear diagnostics.

Background: High-resolution CT is a mainstay of middle ear diagnostics. Middle ear OCT is an emerging, point-of-care diagnostic technology capable of providing volumetric images of the middle ear space without exposing patients to ionizing radiation. To date, OCT imaging in patients has not been directly compared with standard-of-care clinical 3D imaging technology.

Study design: Case series

Setting: Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, Dalhousie University, Halifax, Nova Scotia, Canada

SYNOPSIS: In this case series, three participants who had received high-resolution temporal bone CT scans as part of their standard care underwent middle ear OCT. Case 1, a man in his late 50s, was selected as a healthy control. Case 2, a woman in her late 20s, had suffered a serious traumatic injury resulting in an anterior canal wall laceration and traumatic tympanic membrane (TM) perforation. Case 3, a man in his early 50s, had had surgery for cholesteatoma. Researchers imported the resulting OCT and CT datasets into 3D Slicer for co-registration and fusion. Findings of the three sets of fused imaging showed the complementarity of OCT and CT middle ear imaging. The high resolution and low distortion of both modalities allowed for precise registration of CT and OCT images. Authors noted, for instance, that the TM, often not visible above the noise floor in CT images, is well resolved in OCT. They listed several soft tissue structures that were readily visible in OCT images but difficult to visualize in CT. Conversely, the limited FOV of OCT precluded its use in assessing the penetration of cholesteatoma into the mastoid in Case 3. Study limitations included OCT’s limited FOV.

Citation: Wang J, et al. Fusion of middle ear optical coherence tomography and computed tomography. JAMA Otolaryngol Head Neck Surg. 2025;151:476-484. doi:10.1001/jamaoto.2025.0043.