Low dose (LD, a), HYPR-LR-post-processed low dose (LD+HYPR, b), ultra low dose (ULD, c) and HYPR-LR-post-processed ultra low dose (ULD+HYPR, d) brain perfusion CT of a 75-year old male patient with a lung cancer metastasis adjacent to the right thalamus and chronic left frontal infarction.

<p>Last image of the 60 s time series (1) and the normalized cerebral blood flow (CBF, 2), mean transit time (MTT, 3), time to peak (TTP, 4), cerebral blood volume (CBV, 5) maps. The utilized software does not use reduced matrix reconstructions or spatial smoothing, the images are left noisy. The pathology is recognizable in a, b and d with excellent subjective image quality and low noise in b. No diagnosis possible in c.</p

Subjective image quality scores and and quantitative attenuation measurements of LD and ULD and HYPR-LR post-processed BPCT data sets.

<p>Note: Subjective quality score are reported as mean values.</p

Example images of ultra low dose (ULD), HYPR-LR-post-processed ultra low dose (ULD+HYPR), low dose (LD) and HYPR-LR-post-processed low dose (HYPR+LD) brain perfusion CT of a 58-years old male patient with no pathology.

<p>The images are all reconstructed with the same slice thickness (5 mm) and presented with identical window settings.</p

Correlation of mean attenuation between original and post-processed data sets.

<p>Correlation of mean attenuation between original and post-processed data sets.</p

Mean attenuation values in a corresponding 60 s time series of the ultra low dose (ULD), the HYPR-LR-post-processed ultra low dose (ULD+HYPR), the low dose (LD) and the HYPR-LR-post-processed low dose (HYPR+LD) images.

<p>Mean attenuation values in a corresponding 60 s time series of the ultra low dose (ULD), the HYPR-LR-post-processed ultra low dose (ULD+HYPR), the low dose (LD) and the HYPR-LR-post-processed low dose (HYPR+LD) images.</p

Ultra low dose (ULD), HYPR-LR-post-processed ultra low dose (ULD+HYPR), low dose (LD) and HYPR-LR-post-processed low dose (HYPR+LD) brain perfusion CT of a 35-years old patient with no pathology.

<p>This patient has slightly moved his head several times starting after 8 seconds of the data acquisition. As the HYPR-algorithm is using information of all time frames in the composite image for the calculation of the individual images, this resulted in an artifact visible in all HYPR-LR-post-processed images of this patient with a double contour of the skull and the brain on the right side and a frontal right hypodensity. The frontal right hypodensity was also visible in some non-post-processed images. The subjective image quality of the LD+HYPR image (rated 3) was still preferred to LD and ULD+HYPR (both rated 4). The ULD image was subjectively non-diagnostic (5). In the case of motion artifacts image registration might further improve image quality if used before the HYPR-LR algorithm is applied.</p

Measurements of variables per patient by histology.

<p>StdDev = Standard deviation.</p

Measurements of variables per patient by mutation status.

<p>StdDev = Standard deviation.</p

Overall results of measurements of all mRNA markers.

<p>StdDev = Standard deviation.</p

RNA-quantity was 13.74±15.53 ng, 37.74±41.09 ng and 28.72±44.27 ng in the bronchoscopy group, EBUS TBNA group and CT core biopsy group respectively.

<p>Among them, Tumor RNA-quantity in EBUS TBNA group was significantly higher than in the bronchoscopy group (P = 0.005), while no statistical significance existed between CT-core biopsy and either of the other two methods.</p