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Christopher Herzog,
J Matthias Kerl,
Salvatore De Rosa,
Tuna Tekin,
Eike Boehme,
Sven Liem,
Miriam Scheuchenzuber,
He-Ri Kim,
Ralf W Bauer,
Justin R Silverman,
Peter L Zwerner, Hanns Ackermann,
Thomas J Vogl,
U Joseph Schoepf
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ABSTRACT: PURPOSE: To assess the influence of experience and training on the proficiency in coronary CT angiography (CCTA) interpretation of practitioners with different levels of experience. METHODS AND MATERIALS: Nine radiologist and cardiologist observers with varying prior CCTA experience ranging from novice to expert independently analyzed two case series of 50 catheter-correlated CCTA studies for coronary artery stenosis (0%, ≤49%, 50-74%, 75-99%, or 100%). Results of the first case series were unblinded and presented along with catheter angiography results to each reader before proceeding to the second series. Diagnostic accuracy on a per-segment basis was compared for all readers and both case series, respectively. RESULTS: Correlation coefficients between CCTA and catheter angiography initially ranged between good (r=0.87) and poor (r=0.26), depending on reader experience, and significantly (p<0.05) improved in the second case series (range: r=0.42 to r=0.91). Diagnostic accuracy was significantly (p<0.05) higher for more experienced readers (range: 96.5-97.8%) as compared to less experienced observers (range: 90.7-93.6%). After completion of the second case series for less experienced readers sensitivity and PPV significantly (p<0.05) improved (range: 62.7-67.8%/51.4-84.1%), but still remained significantly (p<0.05) lower as compared to more experienced observers (range: 89.8-93.3%/80.6-93.3%). CONCLUSION: The level of experience appears to be a strong determinant of proficiency in CCTA interpretation. Limited one-time training improves proficiency in novice readers, but not to clinically satisfactory levels.
European journal of radiology 04/2013; · 2.65 Impact Factor
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ABSTRACT: This study was performed to evaluate risk factors predictive of local tumor control after microwave ablation of primary and secondary lung malignancies up to 3 cm in maximal diameter.
The single-antenna microwave ablation treatment of 91 index tumors in 57 patients was studied retrospectively. Time to local tumor progression was monitored on CT scans over the follow-up period. Estimation of overall time to local tumor progression was performed with the Cox regression model. Factors hypothesized to correlate with ablation response included tumor diameter, tumor shape (round or oval versus irregular), clear versus ill-defined tumor margin, adjacency to the pleura, adjacency to bronchi, presence of vessels at least 3 mm in diameter a maximum of 5 mm from the index tumor, energy applied to the index tumor, and the occurrence of cavernous formations after ablation. A logistic regression model was used to correlate the data.
Thirty of 91 (33.0%) index tumors, found in 21 of 57 (36.8%) patients, underwent local progression. The mean time to local tumor progression was 8.3 ± 5.5 months (range 2.1-25.2 months), and the estimated median time to local tumor progression was 22.6 ± 12.4 months. The risk factors that correlated significantly with local tumor progression were a maximal diameter greater than 15.5 mm (p < 0.01), irregular shape of the index tumor (p < 0.01), pleural contact (p = 0.02), and less than 26.7 J/mm(3) applied to the index tumor (p < 0.001). After regression analysis, shape of the index tumor (p = 0.03) and energy deployed per unit volume of the index tumor (p = 0.001) were found to be independent risk factors. Conversely, tumor margin definition (p = 0.06) and proximity of cavernous formations (p = 0.19), juxtatumoral vessels (p = 0.08), and bronchi (p = 0.89) did not affect tumor progression after ablation.
The independent predictive factors for local tumor progression in primary and secondary lung neoplasms up to 3 cm in diameter observed in this study were irregular shape of the index tumor and energy application of less than 26.7 J/mm(3) to the index tumor.
American Journal of Roentgenology 03/2013; 200(3):665-72. · 2.78 Impact Factor
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N N N Naguib,
N-E A Nour-Eldin,
F Serag-Eldin,
Y Z Mazloum,
A F Agameya,
S Abou-Seif,
A N Etaby,
T Lehnert,
T Gruber-Rouh,
S Zangos, H Ackermann,
T J Vogl
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ABSTRACT: Enlargement and dysfunction of the right ventricle (RV) is a sign and outcome predictor of many cardiopulmonary diseases. Due to the complex geometry of the RV exact volumetry is cumbersome and time-consuming. We evaluated the performance of prototype software for fully automated RV segmentation and volumetry from cardiac CT data. In 50 retrospectively ECG-gated coronary CT angiography scans the endsystolic (RVVmin) and enddiastolic (RVVmax) volume of the right ventricle was calculated fully automatically by prototype software. Manual slice segmentation by two independent radiologists served as the reference standard. Measurement periods were compared for both methods. RV volumes calculated with the software were in strong agreement with the results from manual slice segmentation (Bland-Altman r = 0.95-0.98; p < 0.001; Lin's correlation Rho = 0.87-0.96, p < 0.001) for RVVmax and RVVmin with excellent interobserver agreement between both radiologists (r = 0.97; p < 0.001). The measurement period was significantly shorter with the software (153 ± 9 s) than with manual slice segmentation (658 ± 211 s). The prototype software demonstrated very good performance in comparison to the reference standard. It promises robust RV volume results and minimizes postprocessing time.
The international journal of cardiovascular imaging 08/2012; · 2.15 Impact Factor
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N N N Naguib,
N-E A Nour-Eldin,
F Serag-Eldin,
Y Z Mazloum,
A F Agameya,
S Abou-Seif,
A N Etaby,
T Lehnert,
T Gruber-Rouh,
S Zangos, H Ackermann,
T J Vogl
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ABSTRACT: To study Doppler changes in the uterine artery immediately following and 3 months after uterine artery embolization (UAE) and to test the feasibility of using uterine artery Doppler as a predictor of the predominant side of arterial supply to leiomyomas, amount of embolizing material needed and leiomyoma tumor volume at follow-up.
The study included 38 patients undergoing UAE for leiomyomas. Uterine artery Doppler was performed transabdominally before, within 6 hours after and 3 months after UAE to determine the peak systolic (PSV) and end-diastolic (EDV) velocities and resistance index (RI). Leiomyoma volume was measured using contrast-enhanced magnetic resonance imaging (MRI) before and 3 months after UAE. The predominant side of arterial supply to the leiomyoma was determined on digital subtraction angiography using the uterine artery diameter and tumor blush after contrast injection. For correlations with leiomyoma volume, the average PSV, EDV and RI of both sides was used, while for prediction of the predominant side of supply and for correlation with the amount of embolizing material needed, separate measurements from each side were used.
Relative to the pre-embolization value, the uterine artery PSV and EDV were significantly reduced (P < 0.05) immediately following UAE, while the RI was significantly elevated (P < 0.05). For prediction of the predominant side of supply, the lowest RI showed the highest accuracy (81.6%). There was no significant correlation between the pre-embolization PSV, EDV or RI and the amount of embolizing material utilized. Immediately post-embolization EDV and RI values were statistically significantly correlated with the 3-month follow-up leiomyoma volume, with RI showing the strongest correlation (P = 0.0400 and 0.0002, rho = 0.34 and - 0.58, respectively). The leiomyoma volume was predicted to have reduced by 38-61% after 3 months if the immediate post-embolization average RI value was between 0.82 and 0.88.
Pre-interventional Doppler assessment can be used to predict the predominant side of supply to leiomyomas but not the amount of embolizing material needed. Immediate post-interventional Doppler assessment can predict the leiomyoma volume after UAE. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Ultrasound in Obstetrics and Gynecology 12/2011; 40(4):452-8. · 3.01 Impact Factor
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ABSTRACT: The purpose of this article is to compare workflow efficiency between a conventional computed radiography (CR) system and a novel, portable, cassette-sized, and wireless flat-panel digital radiography (DR) system.
Observational time-motion analyses were performed at one site at which CR and the new portable DR system are used concurrently. The workflow steps of both systems were identified and categorized to facilitate comparison. The times required for examination preparation, patient positioning, exposure, postacquisition processing, and the examination as a whole were recorded by a neutral observer. Timing differences between the CR and portable DR systems were compared, and all data were analyzed using commercially available statistical software. Nine general radiographic examination types were selected, with approximately 50 patients per examination type.
A total of 941 examinations (CR, n = 474; portable DR, n = 467) were timed in this study. Total examination time differences between CR and portable DR system (mean, 26.44 seconds; median 26.99 seconds) were found to be statistically significant (p < 0.001), with DR proving faster than CR. The single largest contributor to the time difference between CR and portable DR was postacquisition processing (mean, 26.58 seconds; median, 25.91 seconds), which was a composite of multiple individual steps, including cassette transport (CR only, mean, 13.22 seconds; median, 12.74 seconds), cassette readout (mean, 10.15 seconds; median, 10.4 seconds), and postprocessing (mean, 3.21 seconds; median, 3.11 seconds).
Overall radiographer time was significantly shorter when performing examination-related tasks with the novel, portable DR system than when performing comparable tasks with the CR system, a difference that appears to result largely from technology configuration.
American Journal of Roentgenology 06/2011; 196(6):1368-71. · 2.78 Impact Factor
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ABSTRACT: To investigate the role of perfusion defect (PD) size on dual energy CT pulmonary blood volume assessment as predictor of right heart strain and patient outcome and its correlation with d-dimer levels in acute pulmonary embolism (PE).
53 patients with acute PE who underwent DECT pulmonary angiography were retrospectively analyzed. Pulmonary PD size caused by PE was measured on DE iodine maps and quantified absolutely (VolPD) and relatively to the total lung volume (RelPD). Signs of right heart strain (RHS) on CT were determined. Information on d-dimer levels and readmission for recurrent onset of PE and death was collected.
D-dimer level was mildly (r = 0.43-0.47) correlated with PD size. Patients with RHS had significantly higher VolPD (215 vs. 73 ml) and RelPD (9.9 vs. 2.9%) than patients without RHS (p < 0.003). There were 2 deaths and 1 readmission due of PE in 18 patients with >5% RelPD, while no such events were found for patients with <5% RelPD.
Pulmonary blood volume on DECT in acute PE correlates with RHS and appears to be a predictor of patient outcome in this pilot study.
European Radiology 04/2011; 21(9):1914-21. · 3.22 Impact Factor
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ABSTRACT: To compare the dose estimates and image quality of Dual Energy CT (DECT), Dual Source CT (DSCT) and 16-slice CT for coronary CT angiography (cCTA).
Sixty-eight patients were examined with 16 - slice MDCT (group 1), 68 patients with DSCT (group 2) and 68 patients using DSCT in dual energy mode (DECT group 3). CT dose index volume, dose length product, effective dose, signal-to-noise, and contrast-to-noise ratio were compared. Subjective image quality was rated by two observers, blinded to technique.
The mean estimated radiation dose of all patients investigated on a 16 - slice MDCT was 12 ± 3.59 mSv, for DSCT in single energy 9.8 ± 4.77 mSv and for DECT 4.54 ± 1.87 mSv. Dose for CTA was significantly lower in group 3 compared to group 1 and 2. The image noise was significantly lower in Group 2 in comparison to group 1 and group 3. There was no significant difference in diagnostic image quality comparing DECT and DSCT.
cCTA shows better dose levels at both DECT and DSCT compared to 16-slice CT. Further, DECT delivers significantly less dose than regular DSCT or single source single energy cCTA while maintaining diagnostic image quality.
European Radiology 03/2011; 21(3):530-7. · 3.22 Impact Factor
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ABSTRACT: The purpose of this study was to evaluate interobserver agreement of prostatic MRI in assessing the performance of staging prostate carcinoma in comparison with histopathologic step section prostate specimens.
We retrospectively evaluated 46 patients who underwent prostatic MRI examination at 1.5 T MRI and "subsequently" radical prostatectomy. All MR-images were reevaluated by two different experienced radiologists (15 and 1.5 years of experience) with special focus on T2/T3 differentiation. Both radiologists were not aware of the patient's clinical data, except that the patient had prostate cancer. These findings were compared with histopathologic whole mount step section prostate specimens, which served as the "gold standard". Fourfold tables were created to calculate sensitivity, specificity, positive and negative predictive values and efficiency for T2/T3 differentiation. Cohen's kappa was calculated to measure inter-rater agreement.
Twenty-eight patients were diagnosed with organ defined cancer (T2), 18 patients were staged with extracapsular extension (T3), and thereof 7 patients were staged with seminal vesicle invasion (T3b) by the pathologists. The experienced reader reached a sensitivity of 77.78% (95%-CI 52.36%; 93.59%) and specificity of 92.86% (95%-CI 76.50%; 99.12%) for T2/T3 differentiation, the less experienced reader however achieved a sensitivity of 33.33% (95%-CI 13.34%; 59.01%) and specificity of 71.43% (95%-CI 51.33%; 86.78%). The Cohen's kappa for inter-rater reliability for differentiation between T2 and T3 stage was κ=0.0129.
Evaluation of prostatic MR imaging requires lengthy experience for accurate interpretation and staging. While a highly experienced reader can achieve good correlation with histopathology even without utilization of functional MR imaging, a less experienced reader with theoretical knowledge falls short of expectation.
European journal of radiology 02/2011; 81(3):456-60. · 2.65 Impact Factor
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ABSTRACT: The purpose of this article is to compare the performance of dual-energy CT with that of 3-T MRI with late enhancement for the detection of chronic myocardial infarction during first-pass coronary CT angiography (CTA).
Thirty-six patients underwent coronary CTA for the assessment of coronary bypass graft patency on a first-generation dual-source CT scanner in dual-energy mode. Gray-scale images (100 kV, 140 kV, and blended virtual 120 kV) were assessed for areas of hypodense myocardium during the arterial phase. In addition, a color-coded map of myocardial iodine distribution was calculated from the dual-energy data for perfusion analysis. Dual-energy CT data were compared with data from 3-T MRI with late enhancement, which served as the reference standard for scar detection using the American Heart Association's 17-segment model of the left ventricle.
One hundred one (17%) of 612 myocardial segments in 22 (61%) of 36 patients showed late enhancement on MRI. Although myocardial iodine mapping was prone to artifacts, mostly arising from sternal wires (70% sensitivity), 100-kV gray-scale images showed the highest sensitivity (80%) for the detection of myocardial scar. Blended virtual 120-kV images with lower noise and higher resolution had the best diagnostic accuracy (77% sensitivity, 97% specificity, 85% positive predictive value, 96% negative predictive value, and 94% accuracy).
Detection of chronic myocardial infarction on color-coded iodine distribution analysis with first-generation dual-energy CT is impeded by thoracic metallic devices. This group of patients benefits more from adequate blending of high- and low-kilovoltage gray-scale images. Further technical improvements are desirable to lower artifact burden and improve sensitivity on myocardial iodine distribution mapping.
American Journal of Roentgenology 09/2010; 195(3):639-46. · 2.78 Impact Factor
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ABSTRACT: The purpose of this study was to assess the accuracy of 64-MDCT in the visualization of different coronary artery stents and in the appraisal of in-stent stenosis. MATERIALS AND METhODS: Five different coronary stent types with three diameters (2.5, 3.0, and 4.0 mm) were analyzed using anthropomorphic dynamic cardiac phantom. All stents were mounted on polyurethane sticks of defined outer diameter and contained a default concentric stenosis of 50% each. Imaging was performed at four different heart rates (no motion, 60 beats/min, 75 beats/min, and 90 beats/min). Apparent stent diameter, degree of stenosis, in-stent attenuation, and diagnostic accuracy were assessed.
A significant (p < 0.05) overestimation of the degree of stenosis (41.1% +/- 41.4%), underestimation of the stent lumen (-42.7% +/- 41.4%), and increase in in-stent attenuation (36.6 +/- 29.2 HU) were observed for all stents and heart rates. In-stent stenosis > 50% was detected with an overall sensitivity of 88.9% (95% CI, 75.9-96.3%) and an overall specificity of 51.1% (95% CI, 35.8-66.3%) by observer 1 and with an overall sensitivity of 86.7% (95% CI, 73.2-94.9%) and an overall specificity of 57.8% (95% CI, 42.2-72.3%) by observer 2. A trend toward higher specificity was observed for increasing stent diameter, however, without reaching statistical significance (p = 0.63).
In an experimental setting, 64-MDCT allows a reliable detection of instent stenosis but significantly overestimates the actual degree of stenosis. Within the range of physiologic heart rates, diagnostic accuracy is restricted by spatial, not temporal, resolution.
American Journal of Roentgenology 03/2010; 194(3):W256-62. · 2.78 Impact Factor
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ABSTRACT: Because endomyocardial biopsy has low sensitivity of about 20%, it can be performed near to myocardium that presented as late gadolinium enhancement (LGE) in cardiovascular magnetic resonance (CMR). However the important issue of comparing topography of CMR and histological findings has not yet been investigated. Thus the current study was performed using an animal model of myocarditis.
In 10 male Lewis rats experimental autoimmune myocarditis was induced, 10 rats served as control. On day 21 animals were examined by CMR to compare topographic distribution of LGE to histological inflammation. Sensitivity, specificity, positive and negative predictive values for LGE in diagnosing myocarditis were determined for each segment of myocardium. Latter diagnostic values varied widely depending on topographic distribution of LGE and inflammation as well as on the used CMR sequence. Sensitivity of LGE was up to 76% (left lateral myocardium) and positive predictive values were up to 85% (left lateral myocardium), whereas sensitivity and positive predictive value dropped to 0-33% (left inferior myocardium).
Topographic distribution of LGE and histological inflammation seem to influence sensitivity, specificity, positive and negative predictive values. Nevertheless, positive predictive value for LGE of up to 85% indicates that endomyocardial biopsy should be performed "MR-guided". LGE seems to have greater sensitivity than endomyocardial biopsy for the diagnosis of myocarditis.
Journal of Cardiovascular Magnetic Resonance 01/2010; 12:49. · 3.72 Impact Factor
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ABSTRACT: The antimicrobial activities of folic acid antagonists are supposed to be antagonized by elevated extracellular thymidine concentrations in damaged host tissues. Therefore, this study was aimed at screening for nucleoside analogs that impair bacterial thymidine utilization and analyzing the combined antimicrobial activities of nucleoside analogs and folic acid antagonists in the presence of thymidine. Our screening results revealed that different nucleoside analogs, in particular halogenated derivatives of 2'-deoxyuridine, substantially impaired the bacterial utilization of extracellular thymidine in Staphylococcus aureus. Time-kill methods showed that 5-iodo-2'-deoxyuridine enhanced the extent of killing of trimethoprim-sulfamethoxazole (SXT) at 24 h against S. aureus in the presence of thymidine (200 microg/liter). While SXT (40 mg/liter) alone did not kill bacteria in the presence of thymidine, its combination with the nucleoside analog at a concentration of 8 mumol/liter showed a bactericidal effect. Moreover, 5-iodo-2'-deoxyuridine combined with SXT in the presence of thymidine showed a broad spectrum of activity against several Gram-positive and Gram-negative bacteria. In conclusion, these data provide evidence that the in vitro antimicrobial activity of SXT in the presence of thymidine can be significantly improved by combination with a nucleoside analog.
Antimicrobial Agents and Chemotherapy 12/2009; 54(3):1226-31. · 4.84 Impact Factor
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ABSTRACT: The purpose of this study was to retrospectively evaluate the risk factors involved in the development of pneumothorax during radiofrequency ablation of lung tumors.
This retrospective study covered 124 ablation sessions for lung tumors (10 primary lesions, 114 metastatic lesions) in 82 patients (46 men, 36 women; mean age, 64.0 years) treated between December 2005 and January 2008. The exclusion criteria for ablation therapy were lesions with a maximal diameter greater than 5 cm and the presence of more than five lesions. A bipolar electrode needle was used under CT guidance. Four patients were treated with two ablation electrodes simultaneously.
The incidence of pneumothorax (detected with CT) was 11.3% (14 of 124 sessions). Pneumothorax was graded mild (lung surface retraction, < or = 2 cm), moderate (lung surface retraction, 2-4 cm), or severe (lung surface retraction, > or = 4 cm). Significant risk factors encountered in the development of pneumothorax were age greater than 60 years (p = 0.046), emphysema (p = 0.02), tumor diameter < or = 1.5 cm (p = 0.0008), lesions in lower part of lung, (p = 0.027), aerated lung parenchyma traversed by the needle track for a distance > or = 2.6 cm (p = 0.0017), and traversal of a major pulmonary fissure (p = 0.0004). Pneumothorax developed in one of the four patients in whom multiple electrodes were used. The mean depth of lung lesions complicated by pneumothorax was 2.9 +/- 1.55 cm (range, 0-5.5 cm). Conservative treatment was performed in four of the 14 pneumothorax sessions (28.6%). In six of the 14 sessions (42.9%), immediate complete evacuation was achieved with an intercostal catheter and manual evacuation; chest tube placement was indicated in four sessions (28.6%). Two patients were treated with manual evacuation because evidence of a progressive increase in pneumothorax on the 24-hour follow-up CT scan indicated failure of conservative treatment.
The development of pneumothorax complicating radiofrequency ablation can be unpredictable, but the many risk factors involved can make the incidence higher among some patients than others. Some of these risk factors are technically avoidable and have to be ruled out.
American Journal of Roentgenology 07/2009; 193(1):W43-8. · 2.78 Impact Factor
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ABSTRACT: Ventricular septal defect (VSD) is one of the most serious and life-threatening complications of acute myocardial infarction. The aim of this study was to evaluate the early and long-term results of the patients after surgical repair of postinfarction VSD by infarct exclusion technique.
A total of 32 consecutive patients (mean age, 62.5 +/- 10.5 years) underwent postinfarction VSD repair using a standardized technique in our department. A retrospective analysis of clinical and operative data, predictors of early mortality, and long-term survival was performed. The localization of VSD was posterior in 50% and anterior in 50% of the patients.
The hospital mortality was 31.2% (10 patients). The most common cause of hospital death was persistent low cardiac output. The mortality of the posterior VSD group was significantly lower than that of the anterior VSD group (18.7% and 43.7%, respectively, p = 0.01). Intra-aortic balloon pump support and absence of cardiac shock were significantly associated with a lower risk of hospital mortality (p = 0.0001 and p = 0.0009, respectively). The actuarial survival rates of in-hospital survivors at 5 and 10 years were 79% +/- 2% and 51% +/- 3%, respectively.
The repair of postinfarction VSD by the infarct exclusion is feasible and safe. This technique seems to offer sufficient favorable early and long-term results compared with other techniques. Early indication, preoperative intra-aortic balloon pump support may improve the surgical results. Preoperative cardiogenic shock carries a poor prognosis for this patient group.
The Annals of thoracic surgery 06/2009; 87(5):1421-5. · 3.74 Impact Factor
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ABSTRACT: The aim of the current study was to use an established animal model of autoimmune myocarditis and to judge the ability of cardiovascular MRI (CMR) in quantitatively measuring the extent of myocardial involvement compared with histopathological measurement of severity and extent. Experimental autoimmune myocarditis (EAM) was induced in 10 male Lewis rats. On day 21, all animals were investigated by CMR to measure the extent of late gadolinium enhancement (LGE). Subsequently, histopathological evaluation of the entire heart was performed. All animals of the experimental group fulfilled histopathological criteria of myocarditis, revealing necrosis in seven of eight cases. At reduced heart rate, area of LGE correlated highly with histologically proven area of myocarditis (r = 0.80-0.87, p < 0.05). LGE was mainly located in the anterior (range 50-62.5%) and lateral (range 62.5-75%) left ventricular wall and septum (range 25-50%) with a midwall to subepicardial accentuation. The LGE pattern found by CMR can be regarded as suggestive of EAM. With cellular necrosis being the main mechanism for LGE we were able to show high correlations between CMR examination results and histopathologically proven areas of myocarditis. Thus we think the current animal model can provide the opportunity for further fundamental research into myocarditis.
European Radiology 06/2009; 19(11):2672-8. · 3.22 Impact Factor
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ABSTRACT: To compare quantitative cartilage volume measurement (CVM) using different slice thicknesses.
Ten knees were scanned with a 1.5T MRI (Sonata, Siemens, Erlangen, Germany) using a 3D gradient echo sequence (FLASH, fast low-angle shot). Cartilage volume of the medial and lateral tibial plateau was measured by two independent readers in 1.5mm, 3.0mm and 5.0mm slices using the Argus software application. Accuracy and time effectiveness served as control parameters.
Determining cartilage volume, time for calculation diminished for the lateral tibial plateau from 384.6+/-127.7s and 379.1+/-117.6s to 214.9+/-109.9s and 213.9+/-102.2s to 122.1+/-60.1s and 126.8+/-56.2s and for the medial tibial plateau from 465.0+/-147.7s and 461.8+/-142.7s to 214.0+/-67.9s and 208.9+/-66.2s to 132.6+/-41.5s and 130.6+/-42.0s measuring 1.5mm, 3mm and 5mm slices, respectively. No statistically significant difference between cartilage volume measurements was observed (p>0.05) while very good inter-reader correlation was evaluated.
CVM using 1.5mm slices provides no higher accuracy than cartilage volume measurement in 5mm slices while an overall time saving up to 70% is possible.
European journal of radiology 05/2009; 75(2):241-4. · 2.65 Impact Factor
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ABSTRACT: To volumetrically analyze liver metastases and posttherapeutic findings of the thermally ablated area after thermal ablation with magnetic resonance (MR)-guided laser-induced thermotherapy in a long-term evaluation using contrast-enhanced MR imaging.
The study was approved by the institutional review board, and informed consent was obtained from all patients. In 40 patients (27 women, 13 men; age range, 33-94 years; mean age, 62.5 years) in whom colorectal cancer (n = 20) and breast cancer (n = 20) had metastasized to the liver, initial tumor volume and thermal-induced necrosis after MR-guided laser-induced thermotherapy were retrospectively analyzed. All patients presented with oligonodular liver metastases and underwent follow-up with contrast-enhanced MR imaging for at least 3 years. No concomitant oncologic therapies were performed.
Volumetric MR imaging evaluation depicted 40 metastases with an initial tumor volume less than 5 mL (x = 1.75), nine metastases with initial volume of 5-20 mL (x = 12.35), and eight metastases with initial volume more than 20 mL (x = 50.57). The mean volume of the thermally damaged area was 498% of the initial volume for colorectal cancer metastases and 604% of the initial volume for breast cancer metastases. The ischemic and necrotic volume for colorectal cancer metastases had decreased by a mean of 48.6% after 3 months, by 63% after 6 months, by 70.2% after 12 months, and by 92.2% after 36 months. For breast cancer metastases at 36 months, the necrotic volume had decreased by 80.61%; the reduction in the volume of the thermally damaged region was statistically significantly lower than that of colorectal cancer metastases.
MR-guided laser-induced thermotherapy induced a high volume of thermal ablation; the greatest reduction in the necrotic volume occurred in the first year, and lower values were seen in the next period. The reduction was statistically significantly higher in colorectal cancer metastases.
Radiology 10/2008; 249(3):865-71. · 5.73 Impact Factor
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ABSTRACT: The purpose was to evaluate the effectiveness of transarterial chemoembolization (TACE) in local tumor control and survival in patients with hepatic metastases from renal cell carcinoma (RCC). Prospective evaluation of TACE treatment outcome in 22 patients recruited from 1999 and 2005 was performed. The chemotherapeutic agent used was mitomycin only in 45% of the patients and mitomycin together with gemcitabine in the other 55%. The embolizing materials used in all of the patients were iodized oil (lipiodol) and degradable starch microspheres. Local response was evaluated by MRI and judged according to Response Evaluation Criteria in Solid Tumors (RECIST). Mean and median survival and survival probability after diagnosis and treatment were both calculated by Kaplan-Meier method. Partial response was achieved in 13.7%, stable disease in 59% and progressive disease in 27.3% of patients. Survival time from the diagnosis of metastases ranged from 18 to 307 months and from 2.2 to 35 months from the start of TACE treatment. The median and mean survival times from the date of diagnosis were 68.6 and 102.9 months, respectively. The median and mean survival times from the start of TACE were 8.2 and 11.7 months, respectively. Survival probability from the start of treatment was 31% after 1 year and 6% after 2 years. TACE can result in a favorable local tumor response in patients with hepatic metastases from RCC, but survival results are still limited.
European Radiology 08/2008; 18(7):1456-63. · 3.22 Impact Factor
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ABSTRACT: The aim of this study was to investigate whether the parenchymal lung damage in patients suffering from cystic fibrosis (CF) can be equivalently quantified by the Chrispin-Norman (CN) scores determined with low-field magnetic resonance imaging (MRI) and conventional chest radiography (CXR). Both scores were correlated with pulmonary function tests (PFT) and the Shwachman-Kulczycki method (SKM). To evaluate the comparability of MRI and CXR for different states of the disease, all scores were applied to patients divided into three age groups. Seventy-three CF patients (mean SKM score: 62 +/- 8) with a median age (range) of 14 years (7-32) were included. The mean CN scores determined with both imaging methods were comparable (CXR: 12.1 +/- 4.7; MRI: 12.0 +/- 4.5) and showed high correlation (P < 0.05, R = 0.97). Only weak correlations were found between imaging, PFT, and SKM. Both imaging modalities revealed significantly more severe disease expression with age, while PFT and SKM failed to detect early signs of disease. We conclude that imaging of the lung in CF patients is capable of detecting subtle and early parenchymal destruction before lung function or clinical scoring is affected. Furthermore, low-field MRI revealed high consistency with chest radiography and may be used for a thorough follow-up while avoiding radiation exposure.
European Radiology 06/2008; 18(6):1153-61. · 3.22 Impact Factor
