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Updated: Mar 22, 2026
Author Spotlight: A 3D Digital Model for the Diagnosis and Treatment of Pulmonary Nodules
Published on: May 19, 2023
Pulmonary Nodule Volumetry at Different Low Computed Tomography Radiation Dose Levels With Hybrid and Model-Based
Annemarie M den Harder1, Martin J Willemink, Robbert W van Hamersvelt
1From the Departments of *Radiology and †Respiratory Medicine, University Medical Center, Utrecht; and ‡Department of Radiology, Erasmus Medical Center, Rotterdam, The Netherlands.
Objective:
The aim of the study was to determine the effects of dose reduction and iterative reconstruction (IR) on pulmonary nodule volumetry.
Methods:
In this prospective study, 25 patients scheduled for follow-up of pulmonary nodules were included. Computed tomography acquisitions were acquired at 4 dose levels with a median of 2.1, 1.2, 0.8, and 0.6 mSv. Data were reconstructed with filtered back projection (FBP), hybrid IR, and model-based IR. Volumetry was performed using semiautomatic software.
Results:
At the highest dose level, more than 91% (34/37) of the nodules could be segmented, and at the lowest dose level, this was more than 83%. Thirty-three nodules were included for further analysis. Filtered back projection and hybrid IR did not lead to significant differences, whereas model-based IR resulted in lower volume measurements with a maximum difference of -11% compared with FBP at routine dose.
Conclusions:
Pulmonary nodule volumetry can be accurately performed at a submillisievert dose with both FBP and hybrid IR.
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