Drug dosage in isolated limb perfusion: evaluation of a limb volume model for extremity volume calculation.

BACKGROUND: Exact drug dosing in isolated limb perfusion (ILP) and infusion (ILI) is essential. We developed and evaluated a model for calculating the volume of extremities and compared this model with body weight- and height-dependent parameters. METHODS: The extremity was modeled by a row of coupled truncated cones. The sizes of the truncated cone bases were derived from the circumference measurements of the extremity at predefined levels (5 cm). The resulting volumes were added. This extremity volume model was correlated to the computed tomography (CT) volume data of the extremity (total limb volume). The extremity volume was also correlated with the patient's body weight, body mass index (BMI) and ideal body weight (IBW). The no-fat CT limb volume was correlated with the circumference-measured limb volume corrected by the ideal-body-weight to actual-body-weight ratio (IBW corrected-limb-volume). RESULTS: The correlation between the CT volume and the volume measured by the circumference was high and significant. There was no correlation between the limb volume and the bare body weight, BMI or IBW. The correlation between the no-fat CT volume and IBW-corrected limb volume was high and significant. CONCLUSIONS: An appropriate drug dosing in ILP can be achieved by combining the limb volume with the simple circumference measurements and the IBW to body-weight ratio.

Preoperative MR-guided wire localization for suspicious breast lesions: comparison of manual and automated software calculated targeting.

OBJECTIVES: Preoperative magnetic resonance (MR) guided wire localization is a frequently used tool to target MR-only visible breast lesions. Different techniques are available. Targeting can be performed using automated software or a manual approach. Aim of this study therefore was to compare manually and automated software assisted wire localization of suspicious breast lesions regarding to image time and accurate positioning. METHODS: 60 females with suspicious breast lesions underwent MR-guided wire localization. In 30 patients a manual target calculation and in another 30 patients a software calculated approach was used. Time measurements for MR imaging as well as calculation of the target coordinates were performed. Furthermore size measurements of (i) lesions, (ii) distance to wire anchor as well as, (iii) distance to skin were performed. A Mann-Whitney-test was used for statistical evaluation. RESULTS: Total imaging time was shorter for the automated software calculated approach but failed to show a statistical significant difference (p=0.13). Time for localization of the lesions was significantly shorter for the software based method (p<0.001). Lesion sizes, distances to wire anchor and skin showed no statistically significant differences. CONCLUSIONS: Preoperative MR-guided wire localization of suspicious lesions that are accessible horizontally, a manually or automated software generated target calculation can be used. As MR guided wire localization of breast lesions needs its time in total, a minimal time consuming approach and therefore an automated software calculated targeting (if available) should be preferred.

Virtual 18F-FDG PET/CT bronchoscopy for lymph node staging in non-small-cell lung cancer patients: present and future applications.

Virtual (18)F-fluorodeoxyglucose (FDG) PET/computed tomography (CT) bronchoscopies provide virtually realistic, 3D endoscopic views of the airways combining anatomical and functional data at a high resolution. Today, even very small airways can be imaged by virtual bronchoscopy. (18)F-FDG PET/CT bronchoscopy images are generated from standard whole-body (18)F-FDG PET/CT scan source data without any additional radiation exposure. The purpose of this review was to give an overview over the studies that are currently available, to provide the technical background of (18)F-FDG PET/CT bronchoscopy and to explain the diagnostic accuracy of (18)F-FDG PET/CT bronchoscopy. Moreover, this manuscript highlights potential future applications of this promising new imaging technique.

Diagnostic accuracy of virtual 18F-FDG PET/CT bronchoscopy for the detection of lymph node metastases in non-small cell lung cancer patients.

UNLABELLED: The aim of this study was to determine the diagnostic accuracy of (18)F-FDG PET/CT bronchoscopy for the detection of regional lymph node metastases in non-small cell lung cancer (NSCLC) patients; potential differences in the maximum standardized uptake value (SUVmax), mean SUV (SUVmean), short-axis diameter, and distance to the airways when comparing true-positive (TP), false-positive (FP), true-negative (TN), and false-negative (FN) lymph nodes; the smallest bronchus diameter accessible by virtual bronchoscopy; and the duration from the start of the virtual (18)F-FDG PET/CT bronchoscopy viewing tool until the images were displayed. METHODS: Sixty-one consecutive NSCLC patients (mean age ± SD, 58 ± 10 y) underwent whole-body (18)F-FDG PET/CT. From these data, virtual (18)F-FDG PET/CT bronchoscopies were reconstructed. The duration from the start of the tool until the display of virtual bronchoscopy images was determined. The diagnostic accuracy of (18)F-FDG PET/CT bronchoscopy for the detection of regional lymph node metastases was evaluated on a lesion basis. Axial (18)F-FDG PET/CT scans served as the standard of reference. The SUVmax, SUVmean, short-axis diameter, and distance to the airways of regional lymph nodes were measured. Lymph nodes were classified as TP, FP, TN, and FN. The smallest bronchus diameter accessible by (18)F-FDG PET/CT bronchoscopy was measured. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of virtual (18)F-FDG PET/CT bronchoscopy for the detection of lymph node metastases were 76%, 87%, 85%, 79%, and 81%, respectively. The differences between the SUVmax, SUVmean, short-axis diameter, and distance to the airways of TP and FP as well as TN and FN lymph nodes were statistically significant (P < 0.05). The mean smallest diameter of accessible bronchi by (18)F-FDG PET/CT bronchoscopy was 3 mm. The mean time duration from the start of the virtual (18)F-FDG PET/CT bronchoscopy tool until the display of the images was 22 ± 7 s. CONCLUSION: Virtual fly-through 3-dimensional (18)F-FDG PET/CT bronchoscopy yields a high diagnostic accuracy for the detection of regional lymph node metastases and has access to bronchi even in the periphery of the lung. High SUVmax, high SUVmean, large small-axis diameter, and short distance to the airways aid detection of lymph node metastases with (18)F-FDG PET/CT bronchoscopy.