Intra-Individual Comparison of 124I-PET/CT and 124I-PET/MR Hybrid Imaging of Patients with Resected Differentiated Thyroid Carcinoma: Aspects of Attenuation Correction

Hong Grafe; Maike E Lindemann; Manuel Weber; Julian Kirchner; Ina Binse; Lale Umutlu; Ken Herrmann; Harald H Quick

doi:10.3390/cancers14133040

Intra-Individual Comparison of ¹²⁴I-PET/CT and ¹²⁴I-PET/MR Hybrid Imaging of Patients with Resected Differentiated Thyroid Carcinoma: Aspects of Attenuation Correction

Cancers (Basel). 2022 Jun 21;14(13):3040. doi: 10.3390/cancers14133040.

Authors

Hong Grafe¹, Maike E Lindemann², Manuel Weber¹, Julian Kirchner³, Ina Binse¹, Lale Umutlu⁴, Ken Herrmann¹, Harald H Quick^{2

5}

Affiliations

¹ Department of Nuclear Medicine, University Hospital Essen, University Duisburg-Essen, Hufelandstr. 55, 45147 Essen, Germany.
² High-Field and Hybrid MR Imaging, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany.
³ Department of Diagnostic and Interventional Radiology, Medical Faculty, University Hospital Dusseldorf, 40225 Dusseldorf, Germany.
⁴ Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany.
⁵ Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, 45141 Essen, Germany.

Abstract

Background: This study evaluates the quantitative differences between 124-iodine (I) positron emission tomography/computed tomography (PET/CT) and PET/magnetic resonance imaging (PET/MR) in patients with resected differentiated thyroid carcinoma (DTC).

Methods: N = 43 ¹²⁴I PET/CT and PET/MR exams were included. CT-based attenuation correction (AC) in PET/CT and MR-based AC in PET/MR with bone atlas were compared concerning bone AC in the head-neck region. AC-map artifacts (e.g., dentures) were noted. Standardized uptake values (SUV) were measured in lesions in each PET data reconstruction. Relative differences in SUV_mean were calculated between PET/CT and PET/MR with bone atlas.

Results: Overall, n = 111 ¹²⁴I-avid lesions were detected in all PET/CT, while n = 132 lesions were detected in PET/MR. The median in SUV_mean for n = 98 congruent lesions measured in PET/CT was 12.3. In PET/MR, the median in SUV_mean was 16.6 with bone in MR-based AC.

Conclusions: ¹²⁴I-PET/CT and ¹²⁴I-PET/MR hybrid imaging of patients with DTC after thyroidectomy provides overall comparable quantitative results in a clinical setting despite different patient positioning and AC methods. The overall number of detected ¹²⁴I-avid lesions was higher for PET/MR compared to PET/CT. The measured average SUV_mean values for congruent lesions were higher for PET/MR.

Keywords: 124I-PET/CT; 124I-PET/MR; CT-based AC; MR-based AC; attenuation correction (AC); differentiated thyroid carcinoma; quantitative PET imaging.

Grants and funding

This research received no external funding.