Metal implants influence CT scan parameters leading to increased local radiation exposure: A proposal for correction techniques

Abstract

Metal implants not only deteriorate image quality, but also increase radiation exposure. The purpose of this study was to evaluate the effect of metal hip prosthesis on absorbed radiation dose and assess the efficacy of organ dose modulation (ODM) and metal artifact reduction (MAR) protocols on dose reduction. An anthropomorphic phantom was scanned with and without bilateral metal hip prostheses, and surface and deep level radiation doses were measured at the abdomen and pelvis. Finally, the absorbed radiation doses at pelvic and abdominal cavities in the reference, ODM, and two MAR scans (Gemstone spectral imaging, GE) were compared. The Mann Whitney-U test and Kruskal-Wallis test were performed to compare the volume CT dose index (CTDI vol ) and mean absorbed radiation doses. Unilateral and bilateral metal hip prostheses increased CTDI VOL by 14.4% and 30.5%, respectively. MAR protocols decreased absorbed radiation doses in the pelvis. MAR showed the most significant dose reduction in the deep pelvic cavity followed by ODM. However, MAR protocols increased absorbed radiation doses in the upper abdomen. ODM significantly reduced absorbed radiation in the pelvis and abdomen. In conclusion, metal hip implants increased radiation doses in abdominopelvic CT scans. MAR and ODM techniques reduced absorbed radiation dose in abdominopelvic CT scans with metal hip prostheses.

Improved visualization of the bone-implant interface and osseointegration in ex vivo acetabular cup implants using photon-counting detector CT

“…We used high tube voltages to reduce beam hardening and metal artefacts [ 32 ], and because higher energy photons are more likely to reach the detector even in the presence of metal objects. More photons at the detector lead to improved image quality and therefore, at least theoretically, improved diagnostic accuracy.…”

Computed Tomography in Limb Salvage and Deformity Correction—3D Assessment, Indications, Radiation Exposure, and Safety Considerations

“…Contrast enhancement seems to be valuable only in the evaluation of soft-tissue structures [40]. As metal implants increase radiation exposure, [41] external ring fixators with carbon rings (TSF) and a higher amount of non-metal parts are advantageous compared to full metal devices.…”

“…In a few cases, metal artifacts severely influenced the CT or VRT evaluations of fracture or callus maturation. Metal implants not only deteriorate image quality but also increase radiation exposure [41]. This was not considered in our measurements, as measurements typically took place before metal implantation, and deformity correction was typically performed with a TSF.…”

Clinical Effectiveness of Home‐Based Telerehabilitation Program for Geriatric Hip Fracture Following Total Hip Replacement

“…Data show that total hip replacement (THR) reduces the length of time fractured hip patients stay in bed and the risk of post‐operative complications. The increase in the number of elderly patients has resulted in the rise in THR procedures worldwide 4,5 . Although THR reduces deaths due to hip fractures in elderly patients to some extent, 22–75% of patients with hip fracture undergoing THR do not regain their pre‐injury health status.…”

“…The increase in the number of elderly patients has resulted in the rise in THR procedures worldwide. 4 , 5 Although THR reduces deaths due to hip fractures in elderly patients to some extent, 22–75% of patients with hip fracture undergoing THR do not regain their pre‐injury health status. Their physical condition remains poor, creating a huge socio‐economic burden.…”