Clinical Micro-CT Empowered by Interior Tomography, Robotic Scanning, and Deep Learning.

Mengzhou Li,James Bennett,Josef Uher,Ge Wang,Weiwen Wu,Chuang Niu,Jay T Rubinstein,Zheng Fang,Wenxiang Cong

doi:10.1109/access.2020.3046187

Abstract

While micro-CT systems are instrumental in preclinical research, clinical micro-CT imaging has long been desired with cochlear implantation as a primary application. The structural details of the cochlear implant and the temporal bone require a significantly higher image resolution than that (about 0.2 mm) provided by current medical CT scanners. In this paper, we propose a clinical micro-CT (CMCT) system design integrating conventional spiral cone-beam CT, contemporary interior tomography, deep learning techniques, and the technologies of a micro-focus X-ray source, a photon-counting detector (PCD), and robotic arms for ultrahigh-resolution localized tomography of a freely-selected volume of interest (VOI) at a minimized radiation dose level. The whole system consists of a standard CT scanner for a clinical CT exam and VOI specification, and a robotic micro-CT scanner for a local scan of high spatial and spectral resolution at minimized radiation dose. The prior information from the global scan is also fully utilized for background compensation of the local scan data for accurate and stable VOI reconstruction. Our results and analysis show that the proposed hybrid reconstruction algorithm delivers accurate high-resolution local reconstruction, and is insensitive to the misalignment of the isocenter position, initial view angle and scale mismatch in the data/image registration. These findings demonstrate the feasibility of our system design. We envision that deep learning techniques can be leveraged for optimized imaging performance. With high-resolution imaging, high dose efficiency and low system cost synergistically, our proposed CMCT system has great promise in temporal bone imaging as well as various other clinical applications.

Highlights

I N the clinical practice of otology and neurotology, medical imaging is critical for evaluation and treatment of many diseases [1]
We may initially focus on all the counts in a wide energy window to study the reconstruction performance; i.e., 40keV to 110keV (120 kVp source), for the following considerations: (1) to avoid the blurring from the X-ray fluorescence in the CdTe crystal; (2) to collect most photons that have penetrated through the head; and (3) to reduce the influence of pile-up effects
Two additional HR global scans were performed with fine detection pixels of 0.11 mm and 0.04 mm to produce the reference reconstructions as the ground truth (GT) of the attenuation value and image resolution, respectively

Summary

Introduction

I N the clinical practice of otology and neurotology, medical imaging is critical for evaluation and treatment of many diseases [1]. Temporal bone CT is the primary method of choice for otological imaging [3]. Otosclerosis, temporal bone fracture, congenital aural atresia, cochlear implantation, dehiscent superior semicircular canal, congenital labyrinthine dysplasia, labyrinthine fistula are all disorders or therapies where temporal bone CT is either absolutely necessary or a commonly desired adjunct to surgical management, for diagnosis or planning. Psychophysical and physiological measures are of primary importance, the ability to localize electrodes and depict their 3D anatomical environment in vivo is of great relevance to.

Results

Discussion

Conclusion