Gottfried J. Schaffler

Abdominal multidetector row computed tomography reduction of cost and contrast material dose using saline flush

ObjectiveTo evaluate the potential of a saline solution flush after the contrast material bolus in abdominal multidetector row CT (MDCT) in contrast material dose and cost reduction. MethodsAbdominal MDCT was performed in 78 patients who were assigned randomly to 2 groups receiving 120 mL nonionic contrast material (300 mgI/mL) alone or 100 mL of the same contrast material pushed with 40 mL of saline solution. Mean attenuation values for both groups were measured in the liver, the spleen, the pancreas, the portal vein, the inferior vena cava, and the abdominal aorta. Cost analyses were performed for both groups. ResultsThere was no significant difference in parenchymal and vascular enhancement between both groups. The difference of the enhancement was 2 HU for the liver (P = 0.11), 2 HU for the spleen (P = 0.44), 3 HU for the pancreas (P = 0.38), 9 HU for the portal vein (P = 0.11), 3 HU for the inferior vena cava (P = 0.55), and 10 HU for the aorta (P = 0.06). Taking the costs of contrast material, saline solution, and disposal material into account,

MDCT angiography of the pulmonary arteries: influence of body weight, body mass index, and scan length on arterial enhancement at different iodine flow rates.

7.30 was saved by the patient using a saline solution flush. ConclusionsUsing a saline flush after the contrast material bolus in abdominal MDCT allows an iodine dose reduction of approximately 6 g, or 17%, without impairing mean parenchymal and vascular enhancement and a cost reduction of

CT-anatomy of the nasolacrimal sac and duct.

7.30 per patient.

The 936C>T polymorphism of the gene for vascular endothelial growth factor is associated with 18F-fluorodeoxyglucose uptake

OBJECTIVEnThe purpose of this study was to assess whether body weight, body mass index, and scan length influence arterial enhancement during CT angiography (CTA) of the pulmonary arteries at different iodine flow rates.nnnMATERIALS AND METHODSnCTA examinations of the pulmonary arteries performed for routine clinical care of 120 patients between March and December 2003 were retrospectively evaluated. Patients had received either 120 mL of contrast medium with an iodine concentration of 300 mg I/mL (group A) or 90 mL of contrast medium with an iodine concentration of 400 mg I/mL (group B). The iodine dose was 36 g, and the injection rate was 4 mL/s in all examinations. The iodine flow rate was 1.2 g I/s in group A and 1.6 g I/s in group B. Arterial attenuation along the z-axis was measured per patient, and the influence of body weight, body mass index, and scan length on enhancement of the pulmonary arteries in the two groups was assessed.nnnRESULTSnIn group A and in group B, body weight and body mass index correlated significantly with mean enhancement along the z-axis (r = -0.35 and -0.26 for group A and -0.48 and -0.40 for group B). Scan length showed no correlation with pulmonary attenuation. Mean pulmonary artery enhancement was significantly higher in group B with a difference of 51 H compared with group A.nnnCONCLUSIONnPulmonary artery attenuation in CTA of the pulmonary arteries shows a small but significant correlation with body weight and body mass index independently of the iodine flow rate used. A higher iodine flow rate improves pulmonary artery enhancement.

CT-anatomy of the nasolacrimal sac and duct@@@Anatomie du sac et du conduit lacrymo-nasaux en tomodensitométrie

Recent developments in ophthalmology such as balloon dilatation, stent implantation, laser therapy and endoscopy of the lacrimal drainage system raise the need for a detailed anatomical knowledge of this system. In this study morphometric measurements of the lacrimal drainage system were performed with thin-section axial computed tomography (CT) examinations in 147 patients with no signs of pathology related to the lacrimal drainage system. The mean length of the nasolacrimal duct measured 11.2 ± 2.6mm (range: 6-21 mm), the narrowest diameter was 3.7 ± 0.7 mm (range: 2-7 mm). The mean length of the nasolacrimal sac was 11.8 ± 2.5 mm (range: 6-18 mm). The width of the nasolacrimal sac did not exceed 4 mm unless filled with air. In 43 (29.3%) of the subjects air was visible within the nasolacrimal sac or duct. The knowledge of the morphometry of the lacrimal drainage system enables the ophthalmologist to plan intervention on the lacrimal drainage system precisely and avoid unnecessary manipulations.

Digital image fusion of CT and PET data sets--clinical value in abdominal/pelvic malignancies.

Background: Positron emission tomography (PET) is a an important technology for detection and staging of breast cancer. The method is based upon assessment of glucose metabolism using the 18F-fluorodeoxyglucose (18F-FDG) as glucose analog. A strong variability of 18F-FDG uptake by breast cancer tissue has been reported, the reason for which is not fully understood but may involve vascular density and integrity. A 936C>T polymorphism in the gene for the vascular endothelial growth factor (VEGF) has been associated with VEGF plasma levels and breast cancer risk.Methods: To analyze the role of this polymorphism for 18F-FDG uptake in breast cancer patients, we determined the VEGF genotype in 37 patients in whom PET was performed for detection of metastases. An 18F-FDG uptake score of 1 (low uptake), 2 (medium uptake) or 3 (high uptake) was assigned to each patient.Results: VEGF CC, CT and TT genotypes were found in 28, 8 and 1 patient. Uptake score of 1 was found in three patients, score 2 in 12 patients and score 3 in 22 patients. VEGF genotype was significantly associated with FDG uptake score (χ2 test, p=0.007). The number of 936-T alleles correlated with a lower 18F-FDG uptake score (Spearman correlation test, p=0.032).Conclusion: In the present study the common VEGF 936C>T polymorphisms had a major impact on 18F-FDG uptake in breast cancer patients. If this result can be confirmed in following studies, it might have strong relevance for the use of PET as diagnostic tool.

The Peripheral Intravenous Cannula: A Cause of Venous Air Embolism

SummaryRecent developments in ophthalmology such as balloon dilatation, stent implantation, laser therapy and endoscopy of the lacrimal drainage system raise the need for a detailed anatomical knowledge of this system. In this study morphometric measurements of the lacrimal drainage system were performed with thin-section axial computed tomography (CT) examinations in 147 patients with no signs of pathology related to the lacrimal drainage system. The mean length of the nasolacrimal duct measured 11.2±2.6mm (range: 6–21 mm), the narrowest diameter was 3.7±0.7 mm (range: 2–7 mm). The mean length of the nasolacrimal sac was 11.8±2.5 mm (range: 6–18 mm). The width of the nasolacrimal sac did not exceed 4 mm unless filled with air. In 43 (29.3%) of the subjects air was visible within the nasolacrimal sac or duct. The knowledge of the morphometry of the lacrimal drainage system enables the ophthalmologist to plan intervention on the lacrimal drainage system precisely and avoid unnecessary manipulations.RésuméLes récents progrès en ophtalmologie tels que la dilatation par ballonnet, la pose de sondes, les traitements au laser, lendoscopie du système lacrymal accroissent la nécessité dune connaissance anatomique précise de ce système ; dans cette étude morphométrique, les mesures du système de drainage lacrymal ont été réalisées par tomodensitométrie en coupes fines (CT); létude portait sur 147 patients indemnes de toute pathologie du système de drainage lacrymal. La longueur moyenne du conduit lacrymal était de 11,2±2,6 mm (limites : 6–21 mm) ; le diamètre le plus réduit était de 3,7±0,7 mm (limites : 2–7 mm). La longueur moyenne du sac lacrymo-nasal était de 11,8 mm±2,5 mm (limites 6–18 mm) ; la largeur du sac nexcédait pas 4 mm, en dehors dun remplissage par lair. La présence dair a été décelée dans le sac ou le conduit chez 43 sujets (29,3 %). La connaissance de la morphométrie du système de drainage lacrymal permet à lophtalmologiste de planifier avec précision une intervention sur le système en évitant des manœuvres intempestives.

Preoperative image fusion of fluoro-2-deoxy-D-glucose-positron emission tomography and computed tomography data sets in oral maxillofacial carcinoma potential clinical value

PURPOSEnWe investigated the clinical relevance of digital image fusion of CT and 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) positron emission tomography (PET) studies in patients with suspected abdominal and/or pelvic metastasis.nnnMETHODnNineteen patients with suspected residual/recurrent malignancies underwent CT and [18F]FDG PET studies of the abdomen and/or pelvis. The data sets of both modalities were fused on a digital workstation by automatic adaptation of the pixel size and the slice thickness. Different body positions were corrected by semiautomatic adaptation of the body axes. The fused images were reconstructed in sagittal, coronal, and axial planes.nnnRESULTSnGood spatial correlation between both modalities was achieved in all patients. Image fusion improved the spatial allocation of pathologically increased [18F]FDG uptake in 7 of 35 lesions (20%).nnnCONCLUSIONnThis work suggests that digital image fusion of CT and [18F]FDG PET data sets improves the anatomical localization of foci with increased [18F]FDG enhancement of the retroperitoneum and the abdominal/pelvic wall, respectively.

Non–Small Cell Lung Cancer: Evaluation of Pleural Abnormalities on CT Scans with 18F FDG PET

Venous air embolism has been reported as a complication of invasive diagnostic and therapeutic procedures or accidental trauma. Little is known about the incidence of air embolism after minimal intravenous manipulations, such as the insertion of a peripheral intravenous cannula. Small air emboli in the central veins, central arteries, and cardiac chambers can be detected during electron-beam computed tomography studies of the chest. Electron-beam computed tomography of the chest was performed on 208 patients after the insertion of a peripheral intravenous cannula. The images were analyzed using a digital workstation. Small air embolism was visible in 10 of 208 (4.8%) patients in the following locations: the pulmonary trunk in 6 patients, the right ventricle in 2, the right atrium in 1, and the left brachiocephalic vein in 1. The embolism was asymptomatic in each patient. Although the potential risks in patients with septal defects and shunts remain unclear, caution should be taken with minimal intravenous manipulations.

Pericardial Sinuses and Recesses: Findings at Electrocardiographically Triggered Electron-Beam CT

ObjectiveThe aim was to evaluate the clinical and therapeutic value of digital image fusion of 2-[18]-fluoro-2-deoxy-d-glucose (F18-FDG) positron emission tomography (PET) and computed tomography (CT) in patients suffering from an oral maxillofacial carcinoma. MethodsSeventeen patients (11 male, 6 female; age range: 45–89 years) suffering from an oral maxillofacial carcinoma underwent CT and F18-FDG–PET (333–370 MBq). The data of the 2 imaging modalities were fused on an image workstation. This image fusion was then visualized in the axial, coronal, and sagittal planes. ResultsPET showed a high pathologic FDG uptake in the tumor in 17 of 17 patients. CT detected the tumor in 12 of 17 patients. The image fusion of FDG-PET and CT showed the tumor in 17 of 17 patients. The final diagnosis was carcinoma of the mandible in 9 of 17 patients, carcinoma of the mouth floor in 3 of 17 patients, carcinoma of the tongue in 3 of 17 patients, carcinoma of the roof of the mouth in 1 of 17 patients, and carcinoma of the parotis gland in 1 of 17 patients. ConclusionsPreoperative image fusion of FDG-PET and CT data sets in oral maxillofacial carcinoma is possible in the clinical routine. Combined morphologic (CT) and functional (PET) imaging improves tumor localization even if the tumor is hardly visible on CT because of the artefacts of dental metallic implants (3/17 patients) or because of the small size of the tumor (2/17 patients). Image fusion is helpful for planning possible surgery (visual models) or radiotherapy (exact region of interest).