Respiratory gated and prolonged acquisition 18F-FDG PET improve preoperative assessment of colorectal liver metastases

Abstract

The addition of tailored liver-specific 18F-FDG PET/CT protocols (PL-PET and RGL-PET) to a WB-PET, improved the detection of intrahepatic colorectal metastases, compared to WB-PET alone. Such add-ons can change clinical patient management of potentially resectable colorectal liver metastases.

Respiratory gated PET/CT of the liver: A novel method and its impact on the detection of colorectal liver metastases

“…In contrary to earlier reports, the SUV of CRLM were not statistically significant higher for the rgPET/CT [7,21]. Comparable results with only slightly higher SUV max were reported by Revheim et al [6]. However, the noise level of the respiratory gated PET/CT was reduced by 41% in the same study.…”

“…The present study evaluated the diagnostic performance for CRLM of a new single-bin method with a modified inspiratory breath-hold approach (rgPET/CT) [6,18]. Our results showed no significant differences in sensitivity between PET/CT and rgPET/CT although a tendency towards improved sensitivity for rgPET/CT was found.…”

“…Recent discussions have addressed the reduced diagnostic performance caused by respiratory motion [6][7][8]. Different approaches for measuring the respiratory cycle with pressure sensor equipped belts, optical/infrared-based methods and spirometer/temperature-based methods have been described [9].…”

Intra-individual comparison of PET/CT with different body weight-adapted FDG dosage regimens

“…We did not consider increasing acquisition times per bed position as a parameter for noise reduction as examination times are valuable and cannot be overly extended ( 25 ). Respiratory gating is known to attenuate PET/CT imaging artifacts ( 26 ), improves IQ which may translates into improved detection of lung and liver lesions ( 27 ), but is not routinely performed. Lesion detection or conspicuity was not assessed as patients with liver lesions were excluded from our study to overcome bias from confounding factors, e.g.…”

Respiratory motion during 90Yttrium PET contributes to underestimation of tumor dose and overestimation of normal liver tissue dose

“…Correction for this blurring has been investigated by several groups (4,9,10). Respiratory movement is a known challenge in 18 F-FDG PET imaging of the liver (11), but to the authors’ knowledge, no previous work has been performed on the dosimetric impact of respiratory motion during 90 Y PET imaging after SIRT. By simulating dose volume histograms, the aim of this study was to illustrate the potential errors made in calculated dose to tumor and normal liver tissue by using 90 Y PET as basis for microsphere distribution.…”