Evaluation of an iterative model-based CT reconstruction algorithm by intra-patient comparison of standard and ultra-low-dose examinations.

Background The explosive growth of computer tomography (CT) has led to a growing public health concern about patient and population radiation dose. A recently introduced technique for dose reduction, which can be combined with tube-current modulation, over-beam reduction, and organ-specific dose reduction, is iterative reconstruction (IR). Purpose To evaluate the quality, at different radiation dose levels, of three reconstruction algorithms for diagnostics of patients with proven liver metastases under tumor follow-up.

CT Angiography: Post-processed Contrast Enhancement for Improved Detection of Pulmonary Embolism.

Rationale And Objectives: The study aimed to improve the detection of pulmonary embolism via an iodine contrast enhancement tool in patients who underwent suboptimal enhanced computed tomography angiography (CTA).

Materials And Methods: We evaluated the CT examinations of 41 patients who underwent CTA for evaluation of the pulmonary arteries which suffered from suboptimal contrast enhancement. The contrast enhancement of the reconstructed images was increased via a post-processing tool (vContrast).

Evaluation of an iterative model-based reconstruction algorithm for low-tube-voltage (80 kVp) computed tomography angiography.

The objective of this study was to investigate the improvement in diagnostic quality of an iterative model-based reconstruction (IMBR) algorithm for low-tube-voltage (80-kVp) and low-tube-current in abdominal computed tomography angiography (CTA). A total of 11 patients were imaged on a 256-slice multidetector computed tomography for visualization of the aorta. For all patients, three different reconstructions from the low-tube-voltage data are generated: filtered backprojection (FBP), IMBR, and a mixture of both [Formula: see text].

Volumetric gain of the human pancreas after left partial pancreatic resection: A CT-scan based retrospective study.

Background/objectives: Regeneration of the pancreas has been well characterized in animal models. However, there are conflicting data on the regenerative capacity of the human pancreas. The aim of the present study was to assess the regenerative capacity of the human pancreas.

Validation of a low dose simulation technique for computed tomography images.

Purpose: Evaluation of a new software tool for generation of simulated low-dose computed tomography (CT) images from an original higher dose scan.

Materials And Methods: Original CT scan data (100 mAs, 80 mAs, 60 mAs, 40 mAs, 20 mAs, 10 mAs; 100 kV) of a swine were acquired (approved by the regional governmental commission for animal protection). Simulations of CT acquisition with a lower dose (simulated 10-80 mAs) were calculated using a low-dose simulation algorithm.

Post-therapeutic response evaluation by a combination of endoscopy and CT scan in esophagogastric adenocarcinoma after chemotherapy: better than its reputation.

Background: Neoadjuvant chemotherapy is an accepted standard of care for locally advanced esophagogastric cancer. As only a subgroup benefits, a response-based tailored treatment would be of interest. The aim of our study was the evaluation of the prognostic and predictive value of clinical response in esophagogastric adenocarcinomas.

Automatic detection of osteoporotic vertebral fractures in routine thoracic and abdominal MDCT.

Objectives: To develop a prototype algorithm for automatic spine segmentation in MDCT images and use it to automatically detect osteoporotic vertebral fractures.

Methods: Cross-sectional routine thoracic and abdominal MDCT images of 71 patients including 8 males and 9 females with 25 osteoporotic vertebral fractures and longitudinal MDCT images of 9 patients with 18 incidental fractures in the follow-up MDCT were retrospectively selected. The spine segmentation algorithm localised and identified the vertebrae T5-L5.

Is preoperative chemotherapy followed by surgery the appropriate treatment for signet ring cell containing adenocarcinomas of the esophagogastric junction and stomach?

Background: Recent data suggest primary resection as the preferable approach in patients with signet ring cell gastric cancer (SRC). The aim of our retrospective exploratory study was to evaluate the influence of SRC on prognosis and response in esophagogastric adenocarcinoma treated with neoadjuvant chemotherapy.

Methods: A total of 723 locally advanced esophagogastric adenocarcinomas (cT3/4 N any) documented in a prospective database from two academic centers were classified according to the WHO definition for SRC (more than 50 % SRC) and analyzed for their association with response and prognosis after neoadjuvant treatment.

Does iterative reconstruction lower CT radiation dose: evaluation of 15,000 examinations.

Purpose: Evaluation of 15,000 computed tomography (CT) examinations to investigate if iterative reconstruction (IR) reduces sustainably radiation exposure.

Method And Materials: Information from 15,000 CT examinations was collected, including all aspects of the exams such as scan parameter, patient information, and reconstruction instructions. The examinations were acquired between January 2010 and December 2012, while after 15 months a first generation IR algorithm was installed.

Three-dimensional prediction of free-flap volume in autologous breast reconstruction by CT angiography imaging.

Purpose: The diagnostic use of computer tomography angiography (CTA) to identify perforating blood vessels for abdominal free-flap breast reconstruction was extended to estimate the three-dimensional (3D) preoperative flap volume and to compare it with the real intraoperative flap weights in order to (1) evaluate the accuracy of CTA-based 3D flap volume prediction, and (2) to analyze abdominal tissue estimation for required breast volume reconstruction.

Methods: Preoperative CTA was performed in 54 patients undergoing unilateral breast reconstruction with a free, deep, inferior epigastric artery perforator flap. 3D flap volumes ([Formula: see text]) based on CTA data were calculated and compared with the actual intraoperative flap weight (g).

Interim endoscopy results during neoadjuvant therapy for gastric cancer correlate with histopathological response and prognosis.

Background: Neoadjuvant chemotherapy for locally advanced gastric cancer leads to major histopathological response in less than 30 % of patients. Data on interim endoscopic response assessment do not exist. This exploratory prospective study evaluates early endoscopy after 50 % of the chemotherapy as predictor for later response and prognosis.

Evaluation of a method for improving the detection of hepatocellular carcinoma.

Objective: To improve the detection of liver lesions in patients with hepatocellular carcinoma (HCC) via an iodine contrast enhancement tool.

Methods: Thirty-two patients with clinically proven HCCs underwent imaging with a three-phase protocol on a 256-slice MDCT. The contrast enhancement in the reconstructed slices was improved via a post-processing tool.

Whole-body CT in haemodynamically unstable severely injured patients--a retrospective, multicentre study.

Background: The current common and dogmatic opinion is that whole-body computed tomography (WBCT) should not be performed in major trauma patients in shock. We aimed to assess whether WBCT during trauma-room treatment has any effect on the mortality of severely injured patients in shock.

Methods: In a retrospective multicenter cohort study involving 16719 adult blunt major trauma patients we compared the survival of patients who were in moderate, severe or no shock (systolic blood pressure 90-110,<90 or >110 mmHg) at hospital admission and who received WBCT during resuscitation to those who did not.

Rapid assessment of liver volumetry by a novel automated segmentation algorithm.

Objective: This study aimed to evaluate a novel segmentation software for automated liver volumetry and segmentation regarding segmentation speed and interobserver variability.

Methods: Computed tomographic scans of 20 patients without underlying liver disease and 10 patients with liver metastasis from colorectal cancer were analyzed by a novel segmentation software. Liver segmentation was performed after manual placement of specific landmarks into 9 segments according to the Couinaud model as well as into 4 segments, the latter being import for surgery planning.

A reliable risk score for stage IV esophagogastric cancer.

Background: The role of surgery for patients with metastatic esophagogastric adenocarcinoma (EGC) is not defined. The purpose of this study was to define selection criteria for patients who may benefit from resection following systemic chemotherapy.

Methods: From 1987 to 2007, 160 patients presenting with synchronous metastatic EGC (cT3/4 cNany cM0/1 finally pM1) were treated with chemotherapy followed by resection of the primary tumor and metastases.

A method for improving iodine contrast enhancement in abdominal computed tomography: experimental study in a pig model.

Objectives: To investigate the improvement in diagnostic image quality of an iodine contrast enhancement tool in an animal model for computed tomography (CT).

Methods: One pig was examined over several consecutive days with a CT system. The quantity of iodine as contrast medium (0.

How fibrosis influences imaging and surgical decisions in pancreatic cancer.

Our understanding of pancreatic ductal adenocarcinoma (PDAC) is shifting away from a disease of malignant ductal cells-only, toward a complex system where tumor evolution is a result of interaction of cancer cells with their microenvironment. This change has led to intensification of research focusing on the fibrotic stroma of PDAC. Pancreatic stellate cells (PSCs) are the main fibroblastic cells of the pancreas which are responsible for producing the desmoplasia in chronic pancreatitis (CP) and PDAC.

Bone mineral density measurements of the proximal femur from routine contrast-enhanced MDCT data sets correlate with dual-energy X-ray absorptiometry.

Objectives: To evaluate the utility of femoral bone mineral density (BMD) measurements in routine contrast-enhanced multi-detector computed tomography (ceMDCT) using dual-energy X-ray absorptiometry (DXA) as the reference standard.

Methods: Forty-one patients (33 women, 8 men) underwent DXA measurement of the proximal femur. Subsequently, transverse sections of routine ceMDCT of these patients were used to measure BMD of the femoral head and femoral neck.

[Pitfalls in computed tomography for diffuse liver diseases].

Clinical/methodical Issue: Misinterpretations in liver diagnostics could result in a false diagnosis, such as a parenchymatous damage or a false focal lesion.

Standard Radiological Methods: Computed tomography is a widely used diagnostic tool to visualize liver diseases.

Methodical Innovations: Magnetic resonance imaging (MRI) is often used as a second diagnostic test to answer specific questions.

The role of stroma in pancreatic cancer: diagnostic and therapeutic implications.

Pancreatic ductal adenocarcinoma (PDAC) is one of the five most lethal malignancies worldwide and survival has not improved substantially in the past 30 years. Desmoplasia (abundant fibrotic stroma) is a typical feature of PDAC in humans, and stromal activation commonly starts around precancerous lesions. It is becoming clear that this stromal tissue is not a bystander in disease progression.

[Endoscopic and percutaneous intervention in the long-term treatment of benign biliary stenosis. A 71-year-old patient with cholestasis following radiotherapy].

Benign biliary stenosis can have various causes and requires differentiation from disorders caused by malignant disease. Treatment of benign stenosis is often difficult and includes treatment modalities such as endoscopic, percutaneous or surgical interventions. Exact knowledge of the etiology and localization of the stenosis is essential when selecting the appropriate method of treatment.

Converted lumbar BMD values derived from sagittal reformations of contrast-enhanced MDCT predict incidental osteoporotic vertebral fractures.

We obtained baseline and follow-up bone mineral density (BMD) values of the lumbar spine from sagittal reformations of routine abdominal contrast-enhanced multidetector computed tomography (MDCT) using a reference phantom and assessed their performance in differentiating patients with no, existing, and incidental osteoporotic fractures of the spine. A MDCT-to-QCT (quantitative computed tomography) conversion equation for lumbar BMD measurements was developed by using 15 postmenopausal women (63 ± 12 years), who underwent standard lumbar QCT (L1-L3) and afterward routine abdominal contrast-enhanced MDCT. Sagittal reformations were used for corresponding lumbar BMD measurements.

Comparison of 3'-deoxy-3'-[¹⁸F]fluorothymidine positron emission tomography (FLT PET) and FDG PET/CT for the detection and characterization of pancreatic tumours.

Purpose: Despite recent advances in clinical imaging modalities, differentiation of pancreatic masses remains difficult. Here, we tested the diagnostic accuracy of molecular-based imaging including 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) positron emission tomography (PET) and [(18)F]fluorodeoxyglucose (FDG) PET/CT in patients with suspected pancreatic masses scheduled to undergo surgery.

Methods: A total of 46 patients with pancreatic tumours suspicious for malignancy and scheduled for resective surgery were recruited prospectively.

Adenocarcinomas of the esophagogastric junction are more likely to respond to preoperative chemotherapy than distal gastric cancer.

Background: Preoperative chemotherapy has been shown to improve outcome of patients with adenocarcinoma of the esophagogastric junction (AEG) and gastric cancer (GC), and histopathologic response has been identified as an independent prognostic parameter in these patients. A recent meta-analysis has identified patients with AEG as benefiting more from preoperative chemotherapy than patients with GC. The aim of this retrospective analysis was to prove these findings in an experienced single-center large patient cohort because there are currently no recruiting prospective clinical trials.