Personalized Ultra-Fractionated Stereotactic Adaptive Radiotherapy for Non-Small Cell Lung Cancer Using Varian Ethos Therapy System.

We present a patient treated with personalized ultra-fractionated stereotactic adaptive radiotherapy (PULSAR) for non-small cell lung cancer (NSCLC) using the adaptive Varian Ethos™ system equipped with the novel HyperSight imaging platform. Three pulses of 12 Gy were separated by a pause of four weeks during which the tumor was given enough time to respond to treatment. Only initial planning computed tomography (CT) was acquired on a CT simulator (Siemens Somatom Definition Edge), whereas other pulses were adapted using online cone beam computed tomography (CBCT) images (iCBCT Acuros reconstruction) acquired while the patient was lying on the treatment couch and delivered immediately.

Optimizing Choice of Skin Surrogates for Surface-Guided Stereotactic Body Radiotherapy of Lung Lesions Using Four-Dimensional Computed Tomography.

Image-guided radiotherapy supported by surface guidance can help to track lower lung lesions' respiratory motion while reducing a patient's exposure to ionizing radiation. However, it is not always clear how the skin's respiratory motion magnitude and its correlation with the lung lesion's respiratory motion vary between different skin regions of interest (ROI). Four-dimensional computed tomography (4DCT) images provide information on both the skin and lung respiratory motion and are routinely acquired for the purpose of treatment planning in our institution.

Comparison of 116 Radiosurgery Treatment Plans for Multi-Leaf and Cone Collimator on a Varian Edge Linac: Are Cones Superior in the Daily Routine?

Delivering focused radiation doses via linear accelerators is a crucial component of stereotactic radiosurgery (SRS) for brain metastases. The Varian Edge linear accelerator provides highly conformal radiation therapy through a high-definition multi-leaf collimator (HD120 MLC) and conical collimator (CC). HD120 MLC adapts to the shape of the target volume using movable tungsten leaves, while CC has a block of conical shape (cones).

Liver function quantification of patients with portal vein embolization using dynamic contrast-enhanced MRI for assessment of hepatocyte uptake and elimination.

Purpose: We evaluated pharmacokinetic models which quantify liver function including biliary elimination based on a dynamic Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) technique with sparse data collection feasible in clinical routine.

Methods: Twelve patients with embolized liver segments following interventional treatment of primary liver cancer or hepatic metastasis underwent MRI. During Gd-EOB-DTPA bolus administration, a 3D dynamic gradient-echo (GRE) MRI examination was performed over approx.