Computed Tomography Perfusion Using First Pass Methods for Lung Nodule Characterization

Abstract

CT Perfusion using first pass modeling appears feasible for lung nodule characterization. Given the short acquisition duration used, weaknesses of the modeling methods are exposed. Nonetheless, microvascular characterization in terms of BF, BV, or Kps appears useful in distinguishing malignant from benign nodules.

Differentiation of Malignant and Benign Pulmonary Nodules with Quantitative First-Pass 320–Detector Row Perfusion CT versus FDG PET/CT

“…The perfusion parameters were refl ected by several factors such as the imaging modality, the tracer, the data acquisition temporal resolution, and the mathematical model, although the same initial time-attenuation curves for the pulmonary nodule and the main trunk of the pulmonary artery in each subject were adapted. Therefore, the signifi cantly good or excellent correlations among PF MS , EF PP , and BV PP were not surprising, and consistent with correlations in a previous report ( 23 ), the signifi cant correlation between the perfusion parameters and SUV max was considered to be due to the biologic activities of nodules, resulting blood supply, glucose metabolism, and hypoxia. Therefore, our study results suggest that perfusion CT indexes could in all of the evaluated dynamic fi rst-pass area-detector CT indexes among the malignant nodules, benign nodules with expected low biologic activity, and benign nodules with expected high biologic activity.…”

“…To our knowledge, however, no attempts have been made to adapt this area-detector CT system for evaluation in a fi rst-pass dynamic perfusion study of pulmonary nodules. Although a few models for multidetector CT assessment of the regional perfusion CT parameters of lung cancer and/or lung parenchyma have been proposed (19)(20)(21)(22)(23), to our knowledge only Sitartchouk et al ( 23 ) have discussed the capability of quantitatively assessed dynamic fi rst-pass perfusion multidetector CT indexes for evaluation of pulmonary nodules. In addition, this system can be used to assess the timeattenuation curves for multiple pulmonary nodules at different positions and the main trunk of the pulmonary artery, which is important for simultaneous quantitative analysis of blood fl ow without helical scanning.…”

“…In this study, quantitatively analyzed area-detector CT indexes were calculated by using two models: the maximum slope model and the Patlak plot model (19)(20)(21)(22)(23)(26)(27)(28). With use of the maximum slope model, the perfusion in each nodule was calculated.…”

Protocol modifications for CT perfusion (CTp) examinations of abdomen-pelvic tumors: Impact on radiation dose and data processing time

“…Indeed, several authors have suggested a longer duration of cine acquisition to enable reliable tissue permeability calculations [5,19,20,26,37]. Although a shorter duration of cine phase has radiation dose and computational benefits, progressive shortening of this phase can conceivably also affect the reproducibility of perfusion measurements [19,20,38,39].…”

A Hybrid Breath Hold and Continued Respiration-Triggered Technique for Time-Resolved 3D MRI Perfusion Studies in Lung Cancer

“…Another paper showed that even as CT techniques improve, model-based analysis still requires dynamic imaging over an extended period of time that is typically not achievable by CT. Furthermore, dynamic CT suffers from limited coverage on the z-axis with currently only 2 cm [24]. As in previous publications [25], we used a two-dimensional trueFISP sequence to assess existing motion of the lung and embedded lesions.…”