To review the normal middle ear anatomy and frequently encountered pathology after tympanoplasty and ossicular chain reconstruction (OCR).To describe the normal Cone Beam Computed Tomography (CBCT) appearance of the middle ear after various types of tympanoplasty and OCR.To discuss the CBCT features of common postoperative complications, e.g., prosthesis dislocation and fracture, graft necrosis and recurrence of middle ear pathology.

Cone Beam Computed Tomography (CBCT) is currently routinely used as a low-radiation dose alternative for temporal bone (TB) imaging. High-resolution CT has long been the imaging modality of choice for patients with conductive/mixed hearing loss, as it accurately depicts the clinically and surgically important middle-ear structures and bony labyrinth. It is still used in many institutions instead of CBCT.Tympanoplasty, routinely combined with mastoidectomy and OCR is a surgical procedure designed to reconstruct the sound transmission mechanism of the middle ear with the following objectives: limitation...

CBCT images of the TB are typically acquired with very thin slices and a small field of view to ensure the smallest possible voxel size (usually 0.15mm) and without intravenous contrast material.Multiplanar reconstructions are essential for improved assessment of TB anatomy and of postoperative changes. Sagittal oblique planes parallel (Pöschl) or perpendicular (Stenvers) to the superior semicircular canals (SSCC) are useful for illustrating the long axes of the malleus and incus. Moreover, the Pöschl projection provides one of the best views of the incudostapedial joint...

Postoperative evaluation of the middle ear with CBCT/CT can be challenging because of different existing types of tympanoplasty and OCR procedures, as well as their combinations. Familiarity with the normal post-surgical middle ear and EAC aspect and recognition of abnormal findings are essential to avoid unnecessary procedures and to detect complications, thus contributing to appropriate therapeutic decisions.

S. E. Chiriac: Nothing to disclose N. Guinand: Nothing to disclose P. Senn: Nothing to disclose M. Becker: Nothing to disclose

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