Photon counting CT versus multi-slice CT for radiographic evaluation of postoperative cochlear implantation:...

Cochlear implant surgery is a standard treatment for severe-to-profound hearing loss. Accurate postoperative assessment of cochlear electrode is crucial for patient outcomes. Photon-counting CT (PCCT) has emerged as a novel imaging modality that may surpass multi-slice CT (MSCT) in image quality and metal artifact reduction. This study aimed to compare PCCT and MSCT in the radiographic evaluation of postoperative cochlear implantation.

A retrospective control study was conducted from March 2021 to September 2024, including 35 patients who underwent cochlear implant surgery and received either PCCT or MSCT scans postoperatively. We employ the multiplanar reconstruction (MPR) method to measure the depth of the electrode and conduct both qualitative and quantitative analysis of image quality. The electrode characteristics, anatomic structures and metal artifacts were compared between the two groups by using a four grades system. Finally, we quantitatively assessed the signal-to-noise ratio (SNR) and radiation dose between the two groups.

The PCCT group (n = 16) demonstrated superior image quality with higher mean values of rating scores for the lateral cochlear wall, medial cochlear wall and modiolus compared to the MSCT group (n = 19). The PCCT group also showed significantly better visualization of electrode position (P < 0.001), overall image quality (P = 0.01), and fewer metal artifacts (P = 0.007). The PCCT group had significantly better signal-to-noise ratio and lower radiation dose compared to the MSCT group (P < 0.001).

PCCT suggests potential advantages in terms of image quality, reduced metal artifacts, and lower radiation doses compared to MSCT for postoperative cochlear implant assessment. These advantages suggest that PCCT could potentially serve as a new standard in imaging protocols for patients with cochlear implants.