[Percutaneous paraumbilical embolization of bleeding rectal varices due to portal hypertension]. / Erfolgreiche Behandlung von rezidivierenden Rektumvarizenblutungen mittels perkutaner paraumbilikaler Embolisation bei Pfortaderhochdruck.

Introduction Portal hypertension may lead to severe esophageal or rectal variceal bleeding. Case report We present a case of a 67-year-old patient presenting with recurrent rectal variceal bleeding who was non-responsive to endoscopic treatment. We are reporting on an interventional therapeutic approach found in interdisciplinary consensus. Discussion Endoscopy, surgery or TIPS (transjugular intrahepatic portosystemic shunt) can be performed in patients with gastrointestinal bleeding due to portal hypertension in liver cirrhosis. In cases not suitable for these treatment options, or in cases where these failed to stop the bleeding, radiological percutaneous paraumbilical coil embolization of the portal vein collateral feeding the bleeding could be performed. In our case, as well as in published cases with embolization of jejunal or esophageal hemorrhage, complete stopping of the bleeding could be achieved without further treatment or re-bleeding.

Characteristics, changes and influence of body composition during a 4486 km transcontinental ultramarathon: results from the TransEurope FootRace mobile whole body MRI-project.

BACKGROUND: Almost nothing is known about the medical aspects of runners doing a transcontinental ultramarathon over several weeks. The results of differentiated measurements of changes in body composition during the Transeurope Footrace 2009 using a mobile whole body magnetic resonance (MR) imager are presented and the proposed influence of visceral and somatic adipose and lean tissue distribution on performance tested. METHODS: 22 participants were randomly selected for the repeated MR measurements (intervals: 800 km) with a 1.5 Tesla MR scanner mounted on a mobile unit during the 64-stage 4,486 km ultramarathon. A standardized and validated MRI protocol was used: T1 weighted turbo spin echo sequence, echo time 12 ms, repetition time 490 ms, slice thickness 10 mm, slice distance 10 mm (breath holding examinations). For topographic tissue segmentation and mapping a modified fuzzy c-means algorithm was used. A semi-automatic post-processing of whole body MRI data sets allows reliable analysis of the following body tissue compartments: Total body volume (TV), total somatic (TSV) and total visceral volume (TVV), total adipose (TAT) and total lean tissue (TLT), somatic (SLT) and visceral lean tissue (VLT), somatic (SAT) and visceral adipose tissue (VAT) and somatic adipose soft tissue (SAST). Specific volume changes were tested on significance. Tests on difference and relationship regarding prerace and race performance and non-finishing were done using statistical software SPSS. RESULTS: Total, somatic and visceral volumes showed a significant decrease throughout the race. Adipose tissue showed a significant decrease compared to the start at all measurement times for TAT, SAST and VAT. Lean adipose tissues decreased until the end of the race, but not significantly. The mean relative volume changes of the different tissue compartments at the last measurement compared to the start were: TV -9.5% (SE 1.5%), TSV -9.4% (SE 1.5%), TVV -10.0% (SE 1.4%), TAT -41.3% (SE 2.3%), SAST -48.7% (SE 2.8%), VAT -64.5% (SE 4.6%), intraabdominal adipose tissue (IAAT) -67.3% (SE 4.3%), mediastinal adopose tissue (MAT) -41.5% (SE 7.1%), TLT -1.2% (SE 1.0%), SLT -1.4% (SE 1.1%). Before the start and during the early phase of the Transeurope Footrace 2009, the non-finisher group had a significantly higher percentage volume of TVV, TAT, SAST and VAT compared to the finisher group. VAT correlates significantly with prerace training volume and intensity one year before the race and with 50 km- and 24 hour-race records. Neither prerace body composition nor specific tissue compartment volume changes showed a significant relationship to performance in the last two thirds of the Transeurope Footrace 2009. CONCLUSIONS: With this mobile MRI field study the complex changes in body composition during a multistage ultramarathon could be demonstrated in detail in a new and differentiated way. Participants lost more than half of their adipose tissue. Even lean tissue volume (mainly skeletal muscle tissue) decreased due to the unpreventable chronic negative energy balance during the race. VAT has the fastest and highest decrease compared to SAST and lean tissue compartments during the race. It seems to be the most sensitive morphometric parameter regarding the risk of non-finishing a transcontinental footrace and shows a direct relationship to prerace-performance. However, body volume or body mass and, therefore, fat volume has no correlation with total race performances of ultra-athletes finishing a 4,500 km multistage race.

Sixty-four MDCT achieves higher contrast in pancreas with optimization of scan time delay.

AIM: To compare different multidetector computed tomography (MDCT) protocols to optimize pancreatic contrast enhancement. METHODS: Forty consecutive patients underwent contrast-enhanced biphasic MDCT (arterial and portal-venous phase) using a 64-slice MDCT. In 20 patients, the scan protocol was adapted from a previously used 40-channel MDCT scanner with arterial phase scanning initiated 11.1 s after a threshold of 150 HU was reached in the descending aorta, using automatic bolus tracking (Protocol 1). The 11.1-s delay was changed to 15 s in the other 20 patients to reflect the shorter scanning times on the 64-channel MDCT compared to the previous 40-channel system (Protocol 2). HU values were measured in the head and tail of the pancreas in the arterial and portal-venous phase. RESULTS: Using an 11.1-s delay, 74.2 HU (head) were measured on average in the arterial phase and 111.2 HU (head) were measured using a 15-s delay (P < 0.0001). For the pancreatic tail, the average attenuation level was 76.73 HU (11.1 s) and 99.89 HU (15 s) respectively (P = 0.0002). HU values were also significantly higher in the portal-venous phase [pancreatic head: 70.5 HU (11.1 s) vs 84.0 HU (15 s) (P = 0.0014); pancreatic tail: 67.45 HU (11.1 s) and 77.18 HU (15 s) using Protocol 2 (P = 0.0071)]. CONCLUSION: Sixty-four MDCT may yield a higher contrast in pancreatic study with (appropriate) optimization of scan delay time.

The TransEurope FootRace Project: longitudinal data acquisition in a cluster randomized mobile MRI observational cohort study on 44 endurance runners at a 64-stage 4,486 km transcontinental ultramarathon.

BACKGROUND: The TransEurope FootRace 2009 (TEFR09) was one of the longest transcontinental ultramarathons with an extreme endurance physical load of running nearly 4,500 km in 64 days. The aim of this study was to assess the wide spectrum of adaptive responses in humans regarding the different tissues, organs and functional systems being exposed to such chronic physical endurance load with limited time for regeneration and resulting negative energy balance. A detailed description of the TEFR project and its implemented measuring methods in relation to the hypotheses are presented. METHODS: The most important research tool was a 1.5 Tesla magnetic resonance imaging (MRI) scanner mounted on a mobile unit following the ultra runners from stage to stage each day. Forty-four study volunteers (67% of the participants) were cluster randomized into two groups for MRI measurements (22 subjects each) according to the project protocol with its different research modules: musculoskeletal system, brain and pain perception, cardiovascular system, body composition, and oxidative stress and inflammation. Complementary to the diverse daily mobile MR-measurements on different topics (muscle and joint MRI, T2*-mapping of cartilage, MR-spectroscopy of muscles, functional MRI of the brain, cardiac and vascular cine MRI, whole body MRI) other methods were also used: ice-water pain test, psychometric questionnaires, bioelectrical impedance analysis (BIA), skinfold thickness and limb circumference measurements, daily urine samples, periodic blood samples and electrocardiograms (ECG). RESULTS: Thirty volunteers (68%) reached the finish line at North Cape. The mean total race speed was 8.35 km/hour. Finishers invested 552 hours in total. The completion rate for planned MRI investigations was more than 95%: 741 MR-examinations with 2,637 MRI sequences (more than 200,000 picture data), 5,720 urine samples, 244 blood samples, 205 ECG, 1,018 BIA, 539 anthropological measurements and 150 psychological questionnaires. CONCLUSIONS: This study demonstrates the feasibility of conducting a trial based centrally on mobile MR-measurements which were performed during ten weeks while crossing an entire continent. This article is the reference for contemporary result reports on the different scientific topics of the TEFR project, which may reveal additional new knowledge on the physiological and pathological processes of the functional systems on the organ, cellular and sub-cellular level at the limits of stress and strain of the human body. Please see related articles: http://www.biomedcentral.com/1741-7015/10/76 and http://www.biomedcentral.com/1741-7015/10/77.

Use of magnetic resonance imaging to detect neoplastic meningitis: limited use in leukemia and lymphoma but convincing results in solid tumors.

BACKGROUND: An early diagnosis of meningitis is important to improve patients' survival. Data about a direct comparison of cerebrospinal fluid cytology (CSF-cytology) and MRI are very limited. Therefore, the aim of this study was to compare these two diagnostic modalities in diagnosing meningitis in patients with hematopoietic and solid malignancies. METHODS: In 68 patients suspicious for neoplastic meningitis, cytology and MRI (1.5 T) was performed. The meningeal, pial or intraparenchymal hyperintense signal or contrast enhancement was correlated to the final CNS diagnosis and to cytology. RESULTS: 44 patients (64.7%) had neoplastic meningitis, 21 patients (30.9%) had non-neoplastic meningitis. The sensitivity to diagnose meningeal disease was 49.2% for MRI and 95.4% for cytology (p<0.001). In patients with neoplastic meningitis, sensitivity was 45.5% for MRI and 93.2% for cytology (p<0.001). In patients with infectious meningitis, sensitivity was 57.1% for MRI and 100% for cytology (p=0.0013). In patients with solid tumors, the sensitivity was 84.6% for both diagnostic methods. The sensitivity for MRI was low in patients with leukemia (20.0%) and lymphoma (37.5%). The positive predictive value (PPV) for MRI to differentiate infectious from neoplastic meningitis was high in patients with infectious meningitis (75.0%), in patients with lymphoma (83.3%), and in patients with solid tumors (72.7%). Ppv was low in patients with leukemia (33.3%). CONCLUSION: Diagnostic value of MRI for diagnosing meningitis is especially limited in patients with hematopoietic malignancies. MRI better detected leptomeningeal involvement caused by solid tumors than by leukemia or lymphoma. The ppv to specify neoplastic meningitis depends on tumor subtype.

The role of dynamic, contrast-enhanced MRI in differentiating lung tumor subtypes.

The aim was to correlate dynamic magnetic resonance imaging perfusion parameters of pulmonary tumors with histological tumor classification. Eighty-six patients with lung cancer were examined. A differentiation of non-small cell lung cancer vs. small cell lung cancer was possible with the parameters tumor necrosis, maximum contrast upslope, and the time until the maximum contrast upslope was reached. The beginning of a relevant contrast uptake, the mean time to peak and the time until the maximum contrast upslope was reached allowed a differentiation between squamous cell carcinoma and adenocarcinoma.

Automatic detection of the carotid artery boundary on cross-sectional MR image sequences using a circle model guided dynamic programming.

BACKGROUND: Systematic aerobe training has positive effects on the compliance of dedicated arterial walls. The adaptations of the arterial structure and function are associated with the blood flow-induced changes of the wall shear stress which induced vascular remodelling via nitric oxide delivered from the endothelial cell. In order to assess functional changes of the common carotid artery over time in these processes, a precise measurement technique is necessary. Before this study, a reliable, precise, and quick method to perform this work is not present. METHODS: We propose a fully automated algorithm to analyze the cross-sectional area of the carotid artery in MR image sequences. It contains two phases: (1) position detection of the carotid artery, (2) accurate boundary identification of the carotid artery. In the first phase, we use intensity, area size and shape as features to discriminate the carotid artery from other tissues and vessels. In the second phase, the directional gradient, Hough transform, and circle model guided dynamic programming are used to identify the boundary accurately. RESULTS: We test the system stability using contrast degraded images (contrast resolutions range from 50% to 90%). The unsigned error ranges from 2.86% ± 2.24% to 3.03% ± 2.40%. The test of noise degraded images (SNRs range from 16 to 20 dB) shows the unsigned error ranging from 2.63% ± 2.06% to 3.12% ± 2.11%. The test of raw images has an unsigned error 2.56% ± 2.10% compared to the manual tracings. CONCLUSIONS: We have proposed an automated system which is able to detect carotid artery cross sectional boundary in MRI sequences during heart cycles. The accuracy reaches 2.56% ± 2.10% compared to the manual tracings. The system is stable, reliable and results are reproducible.

Assessment of COPD severity by computed tomography: correlation with lung functional testing.

CT scans of 474 patients with suspected chronic obstructive pulmonary disease (COPD) were retrospectively evaluated by automated software. There was a correlation between the total lung capacity (TLC) and the total lung volume (TLV) (r=.675, P<.001), between the TLC and the total emphysema volume (r=.571, P<.001), as well as between the TLC and the emphysema index (r=.532, P<.001), respectively. The correlation between the TLC and the TLV was dependent on the COPD severity according to the Global Initiative for Chronic Obstructive Lung Disease classification (chi(2)=6.3079, P=.043). The TLC allows a prediction of clinical illness severity.

Lymphangioleiomyomatosis: solitary abdominal manifestation (2009: 9b).

Lymphangioleiomyomatosis (LAM) is a rare disease that usually affects premenopausal woman and is characterized by cystic lung lesions and lymphatic disorders. We report a case of a 23-year-old woman who presented with diffuse, but increasing abdominal pain. Transabdominal ultrasound showed multiple cystic formations. Due to the patient's uncharacteristic symptoms, an exploratory laparotomy with tissue sampling was performed, and the diagnosis of LAM was confirmed by two independent pathologists. With computed tomography a broad abdominal, but no pulmonary, manifestation could be established. During sirolimus therapy the patient showed clinical benefit, but only slight progress in computed tomography.

Liver perfusion with dynamic multidetector-row computed tomography as an objective method to evaluate the efficacy of chemotherapy in patients with colorectal cancer.

A total of 24 liver metastases of colorectal cancer were evaluated by dynamic multiphasic CT. Under chemotherapy, follow-up examinations were performed every 3 months. The tumor marker CEA before vs. after chemotherapy correlated with the mean contrast enhancement within the margin of metastases. The total size of metastases correlated with the size of central necrosis as well as with the size of marginal contrast enhancement. CT is able to quantify perfusion and local activity of liver metastases to determine the efficacy of chemotherapy.

Aortic wall thickness assessed by multidetector computed tomography as a predictor of coronary atherosclerosis.

Purpose of this study was the evaluation of the thoracic aortic wall thickness as a potential identifier of patients at increased risk for future cardiac events. Thoracic aortic wall thickness was measured with MDCT in 160 patients. The CT-scans were implemented as non-invasive coronary angiography studies. Relationships between aortic wall thickness, sex, age, major risk factors and atherosclerotic plaque burden of the coronary arteries were explored. Higher values of maximum aortic wall thickness of the descending aorta (women P = 0.02, men P = 0.01) were found in patients with coronary atherosclerosis, compared to patients with same gender but excluded atherosclerosis. Aortic wall thickness of the mid-portion of the descending aorta of 3.0 mm is associated with coronary artery disease (CAD) with a specificity of 96.6% (sensitivity 27.5%) and a positive predictive value (PPV) of 93.3%. For patients with two or more major risk factors and a maximum wall thickness of equal or more than 2.6 mm we found a PPV of 100%. We conclude that measurements of maximum wall thickness of the descending aorta are a potential tool for detecting patients with coronary atherosclerosis. The potential effect of combining measurements of aortic wall thickness at routine chest CT studies with a possible cardiovascular screening is substantial and merits further study.

Assessment of pneumonia severity: multidetector-row CT in comparison to clinical score CRB-65.

This study involved 92 patients with clinically diagnosed pneumonia. Differences in the frequency of typical pattern were calculated for patients with mild pneumonia and for patients with severe pneumonia (confusion, respiratory rate, blood pressure, 65 years of age and older). The frequency of singular morphologic changes did not differ significantly between the two groups. Empyema and pleural effusion, as well as an atelectasis in combination with patchy infiltrates and a positive bronchogram/multisegmental infiltrates, seem to have an influence on severity of pneumonia.

Evaluation of lung tumor perfusion by dynamic contrast-enhanced MRI.

The characterization of solid pulmonary lesions with imaging methods remains a diagnostic challenge. The aim of this study was to correlate kinetic parameters of dynamic perfusion magnetic resonance imaging (MRI) with histological tumor classification. Dynamic contrast-enhanced MRI of 31 patients with pulmonary masses (five benign lesions, 26 malignant tumors) was acquired in the tumor areas every 20 s for a mean duration of 124 s. Contrast uptake (CU) was measured by signal analysis in regions of interest (ROIs). The beginning and duration of CU, maximum CU (MCU, % of baseline), maximum contrast upslope (%/s) and the delay to the maximum contrast upslope (s) were calculated. All lesions were classified histologically. The beginning of CU correlated significantly with the MCU delay in all lesions (P=.033). The frequency of a plateau phase was higher in malignant tumors compared to benign lesions (P=.031). Masses with a high MCU showed more frequently a washout of contrast medium after a plateau phase (P=.006) and a higher maximum contrast upslope (P<.001). The MCU delay time was shorter in adenocarcinoma than in squamous cell carcinoma (P=.004). These results indicate that dynamic contrast enhanced MRI might become instrumental in differentiating benign from malignant intrapulmonary tumors and distinguishing adenocarcinoma from squamous cell carcinoma.

CT-guided lung biopsy: incidence of pneumothorax after instillation of NaCl into the biopsy track.

This study was conducted to evaluate whether instillation of NaCl 0.9% solution into the biopsy track reduces the incidence of pneumothoraces after CT-guided lung biopsy. A total of 140 consecutive patients with pulmonary lesions were included in this prospective study. All patients were alternatingly assigned to one of two groups: group A in whom the puncture access was sealed by instillation of NaCl 0.9% solution during extraction of the guide needle (n = 70) or group B for whom no sealing was performed (n = 70). CT-guided biopsy was performed with a 18-G coaxial system. Localization of lesion (pleural, peripheral, central), lesion size, needle-pleural angle, rate of pneumothorax and alveolar hemorrhage were evaluated. In group A, the incidence of pneumothorax was lower compared to group B (8%, 6/70 patients vs. 34%, 24/70 patients; P < 0.001). All pneumothoraces occurred directly post punctionem after extraction of the guide needle. One patient in group A and eight patients in group B developed large pneumothoraces requiring chest tube placement (P = 0.01). The frequency of pneumothorax was independent of other variables. After CT-guided biopsy, instillation of NaCl 0.9% solution into the puncture access during extraction of the needle significantly reduces the incidence of pneumothorax.

Performance of integrated FDG-PET/CT for differentiating benign and malignant lung lesions--results from a large prospective clinical trial.

PURPOSE: The purpose of the study was to evaluate prospectively whether integrated 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) is more accurate for determination of malignancy in newly diagnosed pulmonary lesions compared to separate interpretation of CT and FDG-PET. PROCEDURES: Two hundred and seventy-six patients with newly diagnosed lung lesions underwent FDG-PET/CT. Helical CT, FDG-PET, and FDG-PET/CT were interpreted separately to determine the performance of each imaging modality. Histopathology served as reference in all patients, and in further 60 patients, a benign lesion was verified at follow-up (mean follow-up of 1,040 days). RESULTS: Histology revealed malignant lung tumors in 216 of 276 patients. With PET and PET/CT, a significantly lower number of lesions were classified as equivocal compared to CT alone (p < 0.001). Assuming that equivocal lesions are benign, performance of diagnostic tests was as follows: sensitivity, specificity, and accuracy for CT was 94, 75, and 90%, for PET 97, 83, and 94% (p = 0.021), and for PET/CT 96, 87, and 94% (p = 0.010). Assuming that equivocal lesions are malignant, sensitivity, specificity, and accuracy for CT was 99, 37, and 86%, for PET 99, 77, and 94% (p < 0.001), and for PET/CT 98, 68, and 92% (p = 0.002). PET and PET/CT showed the highest concordance (K = 0.912; confidence interval 0.866-0.958). In lesions less than or equal to 3 cm, there was a significant difference in the performance of PET alone and multidetector row CT as well as PET/CT and multidetector row CT (p = 0.007), irrespective if equivocal findings were judged as malignant or benign. CONCLUSION: For differentiation of benign from malignant lung lesions, integrated FDG-PET/CT imaging was significantly more accurate than CT but not FDG-PET. The addition of metabolic imaging (FDG-PET) to morphological imaging (CT) leads to an increase in specificity and significantly reduced equivocal findings and is therefore recommended to further specify newly diagnosed lung lesions.

Comparison of manual and automated size measurements of lung metastases on MDCT images: potential influence on therapeutic decisions.

PURPOSE: The goal of this study was to evaluate the influence of automated measurement of diameter, area, and volume from chest CT scans on therapeutic decisions of lung nodules as compared to manual 2-D measurements. PATIENTS AND METHOD: The retrospective study involved 25 patients with 75 lung metastases. Contrast enhanced CT scans (16 row) of the lung were performed three times during chemotherapy with a mean time interval of 67.9 days between scans. In each patient, three metastases were evaluated (n=225). Automatic measurements were compared to manual assessment for the following parameters: diameter, area, and density. The influence on the therapeutic decisions was evaluated using the RECIST criteria. RESULTS: The maximum diameter measured by the automatic application was on an average 27% (S.D. 39; CI: 0.22-0.32; p<0.0001) higher than the maximum diameter with manual assessment, and the differences depended on metastases size. Based on diameter calculation, manual and automated assessment disagreed in up to 32% of therapeutic decisions. Volumetric assessment tended towards more changes in therapy as compared to diameter calculation. The calculation of mean transversal area of metastases was 36% (S.D. 0.305; CI: -0.40 to -0.32; p<0.0001) less with automated measurement. Therapeutic strategy would be changed in up to 25.7% of nodules using automated area calculation. Automated assessment of nodules' area and volume could influence the therapeutic decisions in up to 51.4% of all nodules. Density of the nodules was not validated to determine the influence on therapeutic decisions. CONCLUSION: There is a discrepancy between the manual and automated size measurement of lung metastases which could be significant.

Evaluating bowel wall vascularity in Crohn's disease: a comparison of dynamic MRI and wideband harmonic imaging contrast-enhanced low MI ultrasound.

This was a prospective comparison of dynamic MRI (1.5 T) and echo-signal enhanced ultrasound in evaluating vascularization in thickened bowel walls cases of Crohn's disease. Twenty-one patients with histologically confirmed Crohn's disease and bowel wall diameters >5 mm were examined by MRI and ultrasound (US). MR sequences: T1w fl2D, T2w, FLASH T1w post-contrast media (CM) applications with fat saturation were used. Dynamic Turbo-FLASH T1w sequences were acquired in the area of maximal thickening of the ileal wall every 1.5 s post-CM application for a total duration of 1 min. US was performed after the application of 1.2 ml of echo-signal enhancer. Contrast uptake was measured by the semiquantitative score and brightness analysis in regions of interest (ROI). Clinical and laboratory findings including Crohn's disease activity indices were documented; MRI and US parameters were correlated. The length of sonographically documented lesions (122+/-75 mm) correlated significantly with the length of thickened bowel segments in MRI (128+/-76 mm; r=0.466; P=0.033). The maximum percent signal enhancement in the terminal ileum at ultrasound (217.5+/-100.1%) showed a high correlation with the findings of MRI (262+/-108%; r=0.623; P=0.003). With both methods, a plateau phase was observed. US and MRI are capable of evaluating local vascularization in the bowel wall objectively.

CT colonography: comparison of a colon dissection display versus 3D endoluminal view for the detection of polyps.

The purpose of this study was to compare sensitivity, specificity, and postprocessing time of a colon dissection approach to regular 3D-endoluminal workup of computed tomography (CT) colonography for the detection of polypoid lesions. Twenty-one patients who had received conventional colonoscopy after CT colonography were selected; 18 patients had either colon polyps or colon cancer and three had no findings. CT colonography was performed using a 4-channel multi-detector-row (MDR) CT in ten cases and a 16-channel MDR-CT in 11 cases. A blinded reader retrospectively evaluated all colonographies using both viewing methods in a randomized order. Thirty-seven polyps were identified by optical colonoscopy. An overall per-lesion sensitivity of 47.1% for lesions smaller than 5 mm, 56.3% for lesions between 5 mm and 10 mm, and 75.0% for lesion larger than 10 mm was calculated using the colon dissection approach. This compared to an overall per-lesion sensitivity of 35.3% (<5 mm), 81.5% (5-10 mm), and 100.0% (>10 mm) using the endoluminal view. The average time consumption for CT colonography evaluation with the colon dissection software was 10 min versus 38 min using the endoluminal view. A colon dissection approach may provide a significant time advantage for evaluation of CT colonography while obtaining a high sensitivity. It is especially superior in the detection of lesions smaller than 5 mm.

Multi-detector row CT: is prospective electrocardiographic triggering improving the detection of small pulmonary tumors?

RATIONALE AND OBJECTIVES: To compare prospectively ECG-triggered multi-detector row computed tomography (ECG-MDR-CT) and multi-detector row computed tomography (MDR-CT) without triggering for the detection of pulmonary tumors. MATERIALS AND METHODS: 100 patients with proven or suspected tumors were referred for CT of the lung for staging of lung metastases. First, a non-enhanced scan was performed using prospective ECG-triggering on a four-row multidetector helical CT scanner, followed by a contrast-enhanced scan without triggering. The diagnostic assessibility in detecting intrapulmonary nodules and mediastinal structures was graded using a 5-point scale (rated 1 = bad to 5 = very good image quality). RESULTS: ECG-MDR-CT images detected a total of 26% more pulmonary nodules than MDR-CT. For tumors <5 mm, the detection rate was 62% higher using ECG-triggered scans (P = .024). Subjective assessment found median demarcation ratings for all pulmonary findings of 4 (ECG-MDR-CT) versus 3 (MDR-CT). Mediastinal structures were delineated better using ECG triggering. The median ranking for demarcation of pulmonary findings <10 mm was 4 on ECG-MDR-CT and 3 on MDR-CT, respectively. For vessels and the left bronchus, the median of demarcation was 4 on triggered images and 2 on MDR-CT, respectively. The median values referring to the demarcation of mediastinal structures were not significantly different between ECG-MDR-CT and MDR-CT. CONCLUSION: Our data indicate the superiority of prospectively triggered ECG-MDR-CT over MDR-CT for the diagnosis of small pulmonary tumors using a 4-row multidetector CT.