Accuracy and reproducibility of a cone beam CT-based virtual parenchymal perfusion algorithm in the prediction of SPECT/CT anatomical and volumetric results during the planification of radioembolization for HCC

Eur Radiol. 2023 May;33(5):3510-3520. doi: 10.1007/s00330-023-09390-w. Epub 2023 Jan 18.


Objectives: To evaluate anatomical and volumetric predictability of a cone beam computed tomography (CBCT)-based virtual parenchymal perfusion (VPP) software for the single-photon-emission computed tomography (SPECT)/CT imaging results during the work-up for transarterial radioembolization (TARE) procedure in patients with hepatocellular carcinoma (HCC).

Methods: VPP was evaluated retrospectively on CBCT data of patients treated by TARE for HCC. 99mTc macroaggregated albumin particles (99mTc-MAA) uptake territories on work-up SPECT/CT was used as ground truth for the evaluation. Semi-quantitative evaluation consisted of the ranking of visual consistency of the parenchymal enhancement and portal vein tumoral involvement on VPP and 99mTc-MAA SPECT/CT, using a three-rank scale and two-rank scale, respectively. Inter-reader agreement was evaluated using a kappa coefficient. Quantitative evaluation included absolute volume error calculation and Pearson correlation between volumes enhanced territories on VPP and 99mTc-MAA SPECT/CT.

Results: Fifty-two CBCTs were performed in 33 included patients. Semi-quantitative evaluation showed a good concordance between actual 99mTc-MAA uptake and the virtual enhanced territories in 73% and 75% of cases; a mild concordance in 12% and 10% and a poor concordance in 15%, for the two readers. Kappa coefficient was 0.86. Portal vein involvement evaluation showed a good concordance in 58.3% and 66.7% for the two readers, respectively, with a kappa coefficient of 0.82. Quantitative evaluation showed a volume error of 0.46 ± 0.78 mL [0.01-3.55], and Pearson R2 factor at 0.75 with a p value < 0.01.

Conclusion: CBCT-based VPP software is accurate and reliable to predict 99mTc-MAA SPECT/CT anatomical and volumetric results in HCC patients during TARE.

Key points: • Virtual parenchymal perfusion (VPP) software is accurate and reliable in the prediction of 99mTc-MAA SPECT volumetric and targeting results in HCC patients during transarterial radioembolization (TARE). • VPP software may be used per-operatively to optimize the microcatheter position for 90Y infusion allowing precise tumor targeting while preserving non-tumoral parenchyma. • Post-operatively, VPP software may allow an accurate estimation of the perfused volume by each arterial branch and, thus, a precise 90Y dosimetry for TARE procedures.

Keywords: Cone-beam computed tomography; Hepatocellular carcinoma; Perfusion; Single-photon emission computed tomography; Software.

MeSH terms

  • Algorithms
  • Carcinoma, Hepatocellular* / diagnostic imaging
  • Carcinoma, Hepatocellular* / radiotherapy
  • Cone-Beam Computed Tomography
  • Embolization, Therapeutic* / methods
  • Humans
  • Liver Neoplasms* / diagnostic imaging
  • Liver Neoplasms* / radiotherapy
  • Microspheres
  • Perfusion
  • Reproducibility of Results
  • Retrospective Studies
  • Software
  • Technetium Tc 99m Aggregated Albumin
  • Tomography, Emission-Computed, Single-Photon / methods
  • Tomography, X-Ray Computed / methods
  • Yttrium Radioisotopes


  • Technetium Tc 99m Aggregated Albumin
  • Yttrium Radioisotopes