Current trends in imaging for otosclerosis and the potential role of photon-counting computed tomography

Abstract

Otosclerosis is a primary otodystrophy that impacts the osseous architecture of the otic capsule within the temporal bone, resulting in progressive hearing loss. High-resolution computed tomog-raphy (HRCT) has traditionally been the gold standard imaging modality in otosclerosis, providing critical information in both diagnosis and surgical planning. However, its sensitivity varies widely. Recent advancements in imaging technology, such as ultra-high-resolution CT (UHRCT), provide higher spatial resolution and lower doses of radiation but, especially if based on cone beam CT (CBCT), face challenges in standardising bone density and are often limited by beam-hardening artefacts in the presence of metallic prostheses. Photon-counting detector CT (PCDCT) represents a promising UHRCT technology that directly converts photons into electrical signals, enhancing dose efficiency and image quality while reducing beam-hardening artefacts. Initial findings seem to indicate that PCDCT offers superior visualisation of otosclerotic foci and prosthesis positioning compared to traditional HRCT. Furthermore, PCDCT allows for less radiation exposure. This review examines the roles that HRCT and UHRCT, based both on CBCT and PCDCT, as well as magnetic resonance imaging, currently have in the imaging evaluation of otosclerosis. The findings highlight that while HRCT remains the standard, UHRCT and particularly PCDCT significantly improve the assessment capabilities, overcoming many limitations of previous technologies. Incorporating PCDCT imaging into routine clinical practice could lead to more precise diagnosis of otosclerosis, better surgical planning, and improved patient outcomes, ultimately granting more tailored and effective treatment strategies for otosclerosis, in line with the goals of precision medicine to optimise patient care.