Dataset Information

Accuracy of multidetector computed tomography with maximum intensity projection technique in the assessment of fissure integrity.

ABSTRACT:

Background

Bronchoscopic lung volume reduction (BLVR) is a potential treatment for patients with severe emphysema, performed through the placement of unidirectional endobronchial valves (EBVs). Their benefits are only achieved in patients that significantly reduce lobar volume, and it is mandatory that the fissures are complete. Fissure evaluation is preferably done by computed tomography, but little is known if its evaluation corresponds to the anatomical findings. The aim of this study is to evaluate the accuracy of thoracic radiologists in the identification of complete fissures by multidetector computed tomography (MDCT) using maximum intensity projection (MIP) technique, compared with direct anatomical evaluation.

Methods

Prospective study, conducted in a single institution. Patients submitted to thoracic surgery had their fissures classified as complete or incomplete by thoracic surgeons and their preoperative chest scans evaluated by three radiologists, blinded for surgical evaluation. With the intraoperative categorization as a reference, the accuracy and concordance of the three thoracic radiologists' evaluation were calculated. The most experienced radiologist evaluated the fissures at two different moments to estimate the intra-observer agreement.

Results

There were included 67 patients, being 37 (55%) males, with a mean age of 64 years. The accuracy of radiological identification of complete fissures ranged from 76.8% for left posterior oblique fissure to 85.1% for left anterior oblique fissure, with the best performance achieved by the most experienced radiologist. The concordance of the radiological evaluation for fissure integrity compared to the surgical assessment (k) was 0.53-0.68. Intra-observer agreement ranged from 0.74 to 0.87.

Conclusions

The evaluation of the fissure integrity by MDCT analysis using MIP technique by thoracic radiologists had high accuracy among the thoracic radiologists.

SUBMITTER: Soder SA

PROVIDER: S-EPMC8828509 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Four-dimensional computed tomography (4D-CT) is commonly used to account for respiratory motion of target volumes in radiotherapy to the thorax. From the 4D-CT acquisition, a maximum-intensity projection (MIP) image set can be created and used to help define the tumor motion envelope or the internal gross tumor volume (iGTV). The purpose of this study was to quantify the differences in automatically contoured target volumes for usage in the delivery of stereotactic body radiation therapy using MIP data sets generated from one of the four methods: (1) 4D-CT phase-binned (PB) based on retrospective phase calculations, (2) 4D-CT phase-corrected phase-binned (PC-PB) based on motion extrema, (3) 4D-CT amplitude-binned (AB), and (4) cine CT built from all available images.MIP image data sets using each of the four methods were generated for a cohort of 28 patients who had prior thoracic 4D-CT scans that exhibited lung tumor motion of at least 1 cm. Each MIP image set was automatically contoured on commercial radiation treatment planning system. Margins were added to the iGTV to observe differences in the final simulated planning target volumes (PTVs).For all patients, the iGTV measured on the MIP generated from the entire cine CT data set (iGTVcine) was the largest. Expressed as a percentage of iGTVcine, 4D-CT iGTV (all sorting methods) ranged from 83.8% to 99.1%, representing differences in the absolute volume ranging from 0.02 to 4.20 cm3; the largest average and range of 4D-CT iGTV measurements was from the PC-PB data set. Expressed as a percentage of PTVcine (expansions applied to iGTVeine), the 4D-CT PTV ranged from 87.6% to 99.6%, representing differences in the absolute volume ranging from 0.08 to 7.42 cm3. Regions of the measured respiratory waveform corresponding to a rapid change of phase or amplitude showed an increased susceptibility to the selection of identical images for adjacent bins. Duplicate image selection was most common in the AB implementation, followed by the PC-PB method. The authors also found that the image associated with the minimum amplitude measurement did not always correlate with the image that showed maximum tumor motion extent.The authors identified cases in which the MIP generated from a 4D-CT sorting process under-represented the iGTV by more than 10% or up to 4.2 cm3 when compared to the iGTVcine. They suggest utilization of a MIP generated from the full cine CT data set to ensure maximum inclusive tumor extent.