Transient dilutional acidosis but no lactic acidosis upon cardiopulmonary bypass in patients undergoing coronary artery bypass grafting.

Introduction: Dilutional acidosis may result from the introduction of a large fluid volume into the patients' systemic circulation, resulting in a considerable dilution of endogenous bicarbonate in the presence of a constant carbon dioxide partial pressure. Its significance or even existence, however, has been strongly questioned. Blood gas samples of patients operated on with standard cardiopulmonary bypass (CPB) were analyzed in order to provide further evidence for the existence of dilutional acidosis.

Comparison of IMRT and VMAT plans with different energy levels using Monte-Carlo algorithm for prostate cancer.

Purpose: To make dosimetric comparisons of volumetric-modulated arc therapy (VMAT) and 7-field intensity-modulated radiotherapy (IMRT) with dynamic MLCs using the Monaco treatment planning system with Monte Carlo algorithm.

Materials And Methods: Single-arc VMAT and 7-field IMRT treatment plans were compared for 12 intermediate risk prostate cancer patients treated with prostate and seminal vesicle radiotherapy. For all patients, the prescribed dose was 78 Gy delivered in 39 fractions.

CT- versus coregistered FDG-PET/CT-based radiation therapy plans for conformal radiotherapy in colorectal liver metastases: a dosimetric comparison.

Purpose: Our aim was to compare computed tomography (CT) and coregistered [(18)F]-fluorodeoxyglucose positron emission tomography CT-(FDG-PET/CT) based delineation of gross tumor volume (GTV) in unresectable colorectal liver metastasis (CRLM).

Materials And Methods: Fifty-four patients with unresectable CRLM were enrolled but 16 were excluded due to detection of additional hepatic metastases in ten on PET/CT scans, precluding radiotherapy because of transcendent critical organ doses beyond tolerable limits; and of extrahepatic metastases in six. For 38 eligible patients, both CT and PET/CT images were acquired, and two 3D conformal plans were made using the CT and FDG-PET/CT fusion data sets.

Evaluation of field-in-field technique for total body irradiation.

Purpose: To evaluate the clinical use of a field-in-field (FIF) technique for total body irradiation (TBI) using a treatment-planning system (TPS) and to verify TPS results with in vivo dose measurements using metal-oxide-semiconductor field-effect transistor (MOSFET) detectors.

Methods And Materials: Clinical and dosimetric data of 10 patients treated with TBI were assessed. Certain radiation parameters were measured using homogenous and regular phantoms at an extended distance of 380 cm, and the results were compared with data from a conventional standard distance of 100 cm.

Dosimetric comparison of the field-in-field technique and tangential wedged beams for breast irradiation.

Purpose: To analyze tangential wedged beam and field-in-field (FIF) technique doses using dose-volume histograms and conformality indices for target volume and healthy tissues within the irradiated volume.

Materials And Methods: Thirty patients treated with breast-conserving surgery and postoperative whole breast radiotherapy were enrolled. Three plans were generated: a standard tangential plan with either one outer field wedge or bilateral wedges, and an FIF plan.

Radiation dose distribution in the external auditory canal with different prosthetic materials: a clinical report.

Radiotherapy (RT) is an essential component of cancer treatment and aims to deliver higher doses at target volumes and lower doses to surrounding organs to achieve higher tumor control with fewer side effects. Significant dose heterogeneities can occur during treatment of irregular surfaces with electron beams, especially in head, neck, and breast tissue. The external ear and external auditory canal have irregular surfaces, which may cause dose heterogeneity, primarily resulting in excessive doses in the normal tissues lining and adjacent to the ear canal.

Comparison of rectal volume definition techniques and their influence on rectal toxicity in patients with prostate cancer treated with 3D conformal radiotherapy: a dose-volume analysis.

Background: To evaluate the impact of four different rectum contouring techniques and rectal toxicities in patients with treated with 3D conformal radiotherapy (3DCRT).

Methods: Clinical and dosimetric data were evaluated for 94 patients who received a total dose 3DCRT of 70 Gy, and rectal doses were compared in four different rectal contouring techniques: the prostate-containing CT sections (method 1); 1 cm above and below the planning target volume (PTV) (method 2); 110 mm starting from the anal verge (method 3); and from the anal verge to the sigmoid flexure (method 4). The percentage of rectal volume receiving RT doses (30-70 Gy) and minimum, mean rectal doses were assessed.