Mapping distribution of brain metastases: does the primary tumor matter?

PURPOSE: Prior reports on the location and sizes of brain metastases almost entirely focus on patients with primary breast and pulmonary cancer. This is the first study comparing multiple other types of cancer that metastasize to the brain. METHODS: This monocentric retrospective study includes 369 untreated patients with 3313 intraaxial brain metastases. Following semi-manual segmentation of metastases on post-contrast T1WI, cumulative spatial probability distribution maps of brain metastases were created for the whole group and for all primary tumors. Furthermore, mixed effects logistic regression model analysis was performed to determine if the primary tumor, patient age, and patient sex influence lesion location. RESULTS: The cerebellum as location of brain metastases was proportionally overrepresented. Breast and pulmonary cancer caused higher number of brain metastases to what would normally be expected. Multivariate analyses revealed a significant accumulation of brain metastases from skin cancer in a frontal and from breast and gastrointestinal cancer in a cerebellar location. CONCLUSION: Distribution of brain metastases is very heterogeneous for the distinct primaries, possibly reflecting the diversity of mechanisms involved in brain metastases formation. In daily clinical practice distribution patters may be beneficial to predict the primary cancer site, if unknown.

Comparison of meniscal T1rho- and T2*-relaxation times in professional female volleyball players and healthy controls using 3T MRI: A pilot study.

PURPOSE: Comparison of meniscal T1rho- and T2*-relaxation times in professional female volleyball players and healthy controls to determine if relaxation times are prolonged in athletes due to compositional meniscal alterations based on extensive and repetitive joint loading. METHODS: The right knee of 20 asymptomatic professional female volleyball players and 20 female controls were examined at 3T MRI. T1rho- and T2*-measurements were performed in sagittal orientation. For quantitative measurements, two readers independently defined two consecutive central slices with the greatest area of the anterior and posterior horn of the lateral (AHLAT; PHLAT) and medial meniscus (AHMED; PHMED). Both readers repeated measurements after a six-week interval on the original MR images. Statistical analysis included intraclass correlation coefficient (ICC), Wilcoxon signed-rank-, Shapiro-Wilk- & Kolmogorov-Smirnov- and Mann-Whitney U-tests. RESULTS: Mean T1rho-relaxation times in the PHMED were significantly prolonged in professional female volleyball players when compared to controls (24.2 ± 4.0 vs 21.1 ± 2.6 ms; p < 0.005). There were no significant differences for the remaining three meniscal horns. T2*-relaxation times revealed no significant differences between athletes and controls. Prolonged T1rho-relaxation times in the PHMED of female volleyball players did not correlate with significant change in T2*-relaxation times within all meniscal subregions. Reproducibility levels were excellent in all segments (Interobserver-ICC: 0.93-0.97 and intraobserver-ICC: 0.97-0.99). CONCLUSION: T1rho-relaxation times were significantly increased in the PHMED of female volleyball players, potentially indicating a predilection to early degenerative meniscal changes. T1rho may serve as a sensitive biomarker at detecting early compositional meniscal alterations in athletes.

Correlation of T2* relaxation times of the retropatellar cartilage with tibial tuberosity-trochlea groove distance in professional soccer players.

The tibial tuberosity-trochlear groove (TT-TG) distance is a radiographic measurement that is used to quantify malalignment of the patellofemoral joint (PFJ) in cross-sectional imaging. There is an ongoing debate about the impact of the TT-TG-distance on lateral patellar instability and the initiating of cartilage degeneration. In this prospective study, the association of T2* relaxation times and TT-TG distances in professional soccer players was analyzed. 36 knees of 18 professional soccer players (age: 21 ± 2.8 years) were evaluated. Participants underwent knee MRI at 3 T. For qualitative image analysis, fat-saturated 2D PD-weighted Fast Spin Echo (FSE) and T1-weighted FSE sequences were used. For quantitative analysis, T2* measurements in 3D data acquisitions were performed. In a qualitative analysis there was no structural cartilage damage and no abnormalities of the patellar and trochlea shape. The highest T2* values (26.7 ± 5.9 ms) were observed in the central compartment of the patella. The mean TT-TG distance was 10 ± 4 mm (range 3-20 mm). There was no significant correlation between TT-TG distance and T2* relaxation times in all three compartments of the retropatellar cartilage. Our study shows that so long as patellar and trochlear morphology is normal, TT-TG distance alone does not affect the tissue structure of the retropatellar cartilage in professional soccer players.

Noise reduction angiographic imaging technology reduces radiation dose during bronchial artery embolization.

PURPOSE: Comparison of radiation doses in patients undergoing angiographic bronchial artery embolization (BAE) before and after a noise reduction imaging technology upgrade. METHODS: We performed a retrospective study of 70 patients undergoing BAE. Procedures were performed before (n=32) and after (n=38) the technology upgrade containing additional filters and improved image-processing. Cumulative air kerma (AK), cumulative dose area product (DAP), number of exposure frames, total fluoroscopy time and amount of contrast agent were recorded. Mean values were calculated and compared using two-tailed t-tests. DSA image quality was assessed independently by two blinded readers and compared using the Wilcoxon signed-rank test. RESULTS: Using the new technology resulted in a significant reduction of 59% in DAP (149.2 (103.1-279.1) vs. 54.8 (38.2-100.7) Gy*cm2, p<0.001) and a significant reduction of 60% for AK (1.3 (0.6-1.9) vs. 0.5 (0.3-0.9) Gy, p<0.001) in comparison to procedures before the upgrade. There was no significant difference between the number of exposure frames in both groups (251±181 vs. 254±133 frames, p=0.07), time of fluoroscopy (28.8 (18.5-50.4) vs. 28.1 (23.3-38.7) min, p=0.73), or the amount of contrast agent used (139.5±70.8 vs. 163.1±63.1ml, p=0.11). No significant difference regarding image quality could be detected (3 (2,3) vs. 3 (2-4), p=0.64). CONCLUSIONS: The new angiographic noise reduction technology significantly decreases the radiation dose during bronchial artery embolization without compromising image quality or increasing time of fluoroscopy or contrast volume.

Radiation dose reduction during transjugular intrahepatic portosystemic shunt implantation using a new imaging technology.

OBJECTIVE: To compare patient radiation dose in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) implantation before and after an imaging-processing technology upgrade. METHODS: In our retrospective single-center-study, cumulative air kerma (AK), cumulative dose area product (DAP), total fluoroscopy time and contrast agent were collected from an age- and BMI-matched collective of 108 patients undergoing TIPS implantation. 54 procedures were performed before and 54 after the technology upgrade. Mean values were calculated and compared using two-tailed t-tests. Two blinded, independent readers assessed DSA image quality using a four-rank likert scale and the Wilcoxcon test. RESULTS: The new technology demonstrated a significant reduction of 57% of mean DAP (402.8 vs. 173.3Gycm2, p<0.001) and a significant reduction of 58% of mean AK (1.7 vs. 0.7Gy, p<0.001) compared to the precursor technology. Time of fluoroscopy (26.4 vs. 27.8min, p=0.45) and amount of contrast agent (109.4 vs. 114.9ml, p=0.62) did not differ significantly between the two groups. The DSA image quality of the new technology was not inferior (2.66 vs. 2.77, p=0.56). CONCLUSIONS: In our study the new imaging technology halved radiation dose in patients undergoing TIPS maintaining sufficient image quality without a significant increase in radiation time or contrast consumption.

Comparison of T2* relaxation times of articular cartilage of the knee in elite professional football players and age-and BMI-matched amateur athletes.

OBJECTIVE: Recent investigation has underlined the potential of quantitative MR imaging to be used as a complementary tool for the diagnosis of cartilage degeneration at an early state. The presented study analyses T2* relaxation times of articular cartilage of the knee in professional athletes and compares the results to age- and BMI (Body Mass Index)-matched healthy amateur athletes. MATERIALS AND METHODS: 22 professional football players and 22 age- and BMI-matched individuals were underwent knee Magnetic Resonance Imaging (MRI) at 3T including qualitative and quantitative analysis. Qualitative analysis included e.g. meniscal tears, joint effusion and bone edema. For quantitative analysis T2* (22 ET: 4.6-53.6ms) measurements in 3D data acquisition were performed. Deep and superficial layers of 22 predefined cartilage segments were analysed. All data sets were postprocessed using a dedicated software tool. Statistical analysis included Student t-test, confidence intervals and a random effects model. RESULTS: In both groups, T2* relaxation times were significantly higher in the superficial compared to the deep layers (p<0.001). Professional athletes had significantly higher relaxation times in eight superficial and three deep cartilage layers in the predefined cartilage segments (p<0.05). Highly significant differences were found in the weight-bearing segments of the lateral superficial femoral condyle (p<0.001). CONCLUSION: Elevated T2* values in cartilage layers of professional football players compared to amateur athletes were noted. The effects seem to predominate in superficial cartilage layers.

Evaluation of measurement of human TNF in plasma by ELISA.

The performance of a sandwich-ELISA for TNF measurement in plasma and serum was studied. The ELISA was first statistically analyzed. Interassay coefficient of variance and the intraassay coefficient of variance for the concentration range between 0.5 and 5 ng/ml was less than 10%. The sensitivity of the sandwich-ELISA for TNF in culture medium was 10 pg/ml. The ELISA was shown to be specific for biologically active TNF, since a good correlation between the ELISA and the WEHI bioassay was observed when partially inactive, denatured TNF was measured. The effect of various anticoagulation systems on the reliability of human TNF measurement has been evaluated. The oxalate/NaF and EDTA systems were both appropriate, as appeared from the observed blockade of the production of TNF in the tube, either in the cell-glycolysis-blocked or in the calcium-depleted situation, respectively. An eventual decrease in the recovery of rTNF after collection of blood was prevented in the oxalate/NaF tubes. Recovery of TNF in the ELISA was diminished in the presence of plasma or serum. Techniques to enhance the efficiency of the measurement of TNF in plasma by ELISA were compared. The data indicate that in the presence of 1.1 M NaCl, the TNF masking effect of normal plasma was largely abrogated. The presence and role of inhibiting plasma components in plasma of healthy and diseased individuals are discussed.

Potent anti-tumor effects of an anti-CD24 ricin A-chain immunotoxin in vitro and in a disseminated human Burkitt's lymphoma model in SCID mice.

A new anti-CD24 immunotoxin (IT), SWA11.dgA, was constructed by coupling the MAb SWA11 via the bivalent linker SMPT to deglycosylated ricin A-chain (dgA). The effects of SWA11.dgA were evaluated in vitro against the B-precursor leukemia cell line REH, the non-B-non-T acute lymphoblastic leukemia cell line NALM-6 and the Burkitt's lymphoma cell lines BL-2 and BL-38. Binding of SWA11 to the CD24 antigen was assessed by flow cytometry demonstrating high affinity of the MAb for all cell lines tested. SWA11.dgA inhibited the protein synthesis of BL-38, NALM-6, REH and BL-2 cells by 50% at concentrations (IC50) of 4.0 x 10(-11) M, 6.0 x 10(-11) M, 8.0 x 10(-11) M and 3.0 x 10(-9) M, respectively. SWA11.dgA was subsequently used for the treatment of disseminated human BL-38 Burkitt's lymphoma in a newly developed SCID mouse model. The mean survival time (MST) of BL-38-bearing SCID mice was extended from 23 days in untreated controls to more than 230 days when 6 microg SWA11.dgA was applied intraperitoneally one day after tumor challenge. All of the animals achieved continuous complete remissions. SCID mice treated with SWA11.dgA 4 days after tumor cell challenge or a reduced dose of SWA11.dgA (67%) also had a significantly extended MST (45.0 and 51.4 days, respectively, as compared to 22.7 and 23.1 days in the controls). We conclude that SWA11.dgA might be of potential use for the treatment of lymphoma in man.