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Volumetric Assessment of Epicardial Adipose Tissue With Cardiovascular Magnetic Resonance Imaging

Objective: Previous studies determined the amount of epicardial fat by measuring the right ventricular epicardial fat thickness. However, it is not proven whether this one‐dimensional method correlates well with the absolute amount of epicardial fat. In this prospective study, a new cardiovascular magnetic resonance imaging (CMR) method using the three‐dimensional summation of slices method was introduced to assess the total amount of epicardial fat.

Contrast-enhanced dual-energy CT of gastrointestinal stromal tumors: is iodine-related attenuation a potential indicator of tumor response?

Objectives:To assess the correlation of true nonenhanced (TNE) and virtually nonenhanced (VNE) images of abdominal dual-energy computed tomography (DECT) in patients with metastatic gastrointestinal stromal tumors (GIST), and further to investigate the correlation of iodine-related attenuation (IRA) of DECT with the Choi criteria. Material and Methods:Twenty-four consecutive patients (5 women aged 61 ± 10 years) with metastatic GIST underwent DECT of the abdomen (80 kV, 140 kV) using first-generation dual-source computed tomography (CT). All patients had at least one or more liver lesions (median, 4; maximum, 9). Image data were processed with a dedicated DECT software algorithm designed for evaluation of iodine distribution in soft tissue lesions, and VNE CT images were generated. The tumor density (according to Choi criteria) and the maximum transverse diameter of the lesions (according to Response Evaluation Criteria in Solid Tumors [RECIST]) were determined. TNE and VNE lesion attenuation and Choi criteria and IRA were correlated with each other. Results:A total of 291 liver lesions were evaluated, of which 220 were cystic and 71 were solid. The mean lesion size was 4.5 ± 3.2 cm (1.1–18.7 cm). The mean attenuation of all lesions was significantly higher in the TNE images than in the VNE images (P=0.0001). Pearson statistics revealed an excellent correlation of r=0.843 (P=0.0001) between IRA and Choi criteria for all lesions. DECT showed significantly higher IRA in progressive (23.3 ± 9.5 HU) lesions compared with stable or regressive (17.8 ± 9.1 HU) lesions (P=0.0185). Similarly, the Choi criteria differed significantly between progressive (39.9 ± 12.8 HU) and stable/regressive (31.1 ± 10.3 HU) lesions (P=0.0003). Conclusions:DECT is a promising imaging method for the assessment of treatment response in GIST, as IRA might be a more robust response parameter than the Choi criteria. VNE CT data calculated from DECT may eliminate the need for acquisition of a separate unenhanced data set.

Cetuximab-Based Treatment of Metastatic Anal Cancer: Correlation of Response with KRAS Mutational Status

Background: No standard chemotherapy regimen can be defined for patients with metastatic squamous cell carcinoma of the anus due to the low incidence of this disease and the high cure rate of localized tumors. Anal cancers universally express the epidermal growth factor receptor (EGFR) and KRAS mutations have not been reported in anal cancer thus far. Methods: We report on 7 patients with metastatic anal cancer treated with cetuximab – a chimeric antibody against EGFR – on a compassionate use basis along with the results of KRAS mutational analysis. Results: Marked tumor shrinkage was noted in several patients using cetuximab monotherapy or cetuximab/irinotecan combination as first or subsequent treatment line (usually after failure of cisplatin-based regimens). Two out of seven patients harbored KRAS mutations. Both patients had progressive disease receiving cetuximab, while the remaining 5 patients had either a partial remission (n = 3), a minor remission (n = 1) or no change lasting ≥6 months after previous rapid tumor progression. Conclusion: Cetuximab-based treatment appears to be a valuable treatment option for patients with metastatic KRAS wild-type anal cancer after failure of or as an alternative to cisplatin/5-fluorouracil-based therapy.

MR Lung Volume in Fetal Congenital Diaphragmatic Hernia : Logistic Regression Analysis Mortality and Extracorporeal Membrane Oxygenation

PURPOSE To prospectively assess the results of logistic regression analysis that were based on magnetic resonance (MR) image fetal lung volume (FLV) measurements to predict survival and the corresponding need for extracorporeal membrane oxygenation (ECMO) therapy in fetuses with congenital diaphragmatic hernia (CDH) before and after 30 weeks gestation. MATERIALS AND METHODS Written informed consent was obtained and the study was approved by the local research ethics committee. FLV was measured on MR images in 95 fetuses (52 female neonates, 43 male neonates) with CDH between 22 and 39 weeks gestation by using multiplanar T2-weighted half-Fourier acquired single-shot turbo spin-echo MR imaging. On the basis of logistic regression analysis results, mortality and the need for ECMO therapy were calculated for fetuses before and after 30 weeks gestation. RESULTS Overall, higher FLV was associated with improved survival (P < .001) and decreasing probability of need for ECMO therapy (P = .008). Survival at discharge was 29.2% in neonates with an FLV of 5 mL, compared with 99.7% in neonates with an FLV of 25 mL. The corresponding need for ECMO therapy was 56.1% in fetuses with an FLV of 5 mL and 8.7% in fetuses with an FLV of 40 mL. Prognostic power was considerably lower before 30 weeks gestation. CONCLUSION Beyond 30 weeks gestation, logistic regression analysis that is based on MR FLV measurements is useful to estimate neonatal survival rates and ECMO requirements. Prior to 30 weeks gestation, the method is not reliable and the FLV measurement should be repeated, particularly in fetuses with small lung volumes, before a decision is made about therapeutic options.

Frameless stereotactic radiosurgery of a solitary liver metastasis using active breathing control and stereotactic ultrasound.

Background and Purpose:Radiosurgery of liver metastases is effective but a technical challenge due to respiration-induced movement. The authors report on the initial experience of the combination of active breathing control (ABC®) with stereotactic ultrasound (B-mode acquisition and targeting [BAT®]) for frameless radiosurgery.Patients and Methods:A patient with a solitary, inoperable liver metastasis from cholangiocellular carcinoma is presented (Figure 4). ABC® (Figure 3) was used for tumor/liver immobilization. Tumor/liver position was controlled and corrected using ultrasound (BAT®; Figure 1). The tumor was irradiated with a single dose of 24 Gy.Results:Using ABC®, the motion of the tumor was significantly reduced and the overall positioning error was < 5 mm (Figure 2). BAT® allowed a rapid localization of the lesion during breath hold which could be performed without difficulties for 20 s. Overall treatment time was acceptable (30 min).Conclusion:Frameless stereotactic radiotherapy with the combination of ABC® and BAT® allows the delivery of high single doses to targets accessible to ultrasound with high precision comparable to a frame-based approach.Hintergrund und Ziel:Die Radiochirurgie solitärer Lebermetastasen ist effektiv, stellt jedoch aufgrund der Atembewegung des Targets eine technische Herausforderung dar. Die Autoren berichten über die initiale Erfahrung mit der rahmenlosen Radiochirurgie durch die Kombination einer aktiven Atmungskontrolle („active breathing control“ [ABC®]) mit dem stereotaktischen Ultraschall („B-mode acquisition and targeting“ [BAT®]).Patient und Methodik:Präsentiert wird ein Patient mit einer solitären Lebermetastase bei cholangiozellulärem Karzinom (Abbildung 4). ABC® (Abbildung 3) wurde zur Immobilisation des Tumors bzw. der Leber verwendet. Die Position des Tumors bzw. der Leber wurde mit Ultraschall (BAT®) kontrolliert und ggf. korrigiert (Abbildung 1). Der Tumor wurde mit einer Einzeldosis von 24 Gy konformal bestrahlt.Ergebnisse:Durch ABC® konnte die Leber-/Tumorbewegung minimiert werden, die gesamte Positionierungsunsicherheit betrug < 5 mm (Abbildung 2). BAT® erlaubte eine schnelle Lokalisierung des Zielvolumens unter Atemanhalt, was wiederholt über 20 s vom Patienten problemlos ausgeführt wurde. Die Gesamtbehandlungszeit war gegenüber einer ungetriggerten Behandlung kaum verlängert (30 min).Schlussfolgerung:Die rahmenlose Stereotaxie durch Kombination von ABC® und BAT® erlaubt, bei sonographisch zugänglichen Zielvolumina hohe Dosen zu applizieren. Die erreichte Präzision liegt im Bereich jener von rahmenbasierten Verfahren.

Long-term follow up of children with head injuries-classified as good recovery using the Glasgow Outcome Scale : neurological, neuropsychological and magnetic resonance imaging results

AbstractThe primary issues addressed in this study were: (1) determination of the significance of the classification “good outcome” utilizing the Glasgow Outcome Scale (GOS) in children at least 1 year after brain injury; (2) detection of residual lesions of brain parenchyma in these children upon follow up MRI scans; and (3) detection of relationships between neuropsychological test performance and MRI results. Selection criteria included children 6–15 years of age at the time of testing who received an initial CT scan at the time of their head injury and who had been injured at least 12 months prior to the follow up test. Only children who did not demonstrate neurological disability at the time of follow up examination were selected. The children showed a status of “good outcome” as defined by the GOS. Neurological examination, neuropsychological tests and an MRI were done. The test results of 59 patients were compared to those of a matched control group. Children, after receiving head injuries, showed significantly poorer results with respect to cognitive, motor and fine motor skills. Of all MRI-scans 66% revealed pathological findings. Cortical lesions were detected on MRI in 14% of cases; subcortical injuries were detected in 12% and, deep white matter lesions in 31%. Furthermore, corpus callosum damage was observed in 26% of cases. Pathological MRI findings were also observed in children with mild head injuries. All of the children with normal MRI findings showed abilities comparable to those of children in the control group. Patients with cortical lesions exhibited only motor deficits, whereas motor and cognitive deficits were seen in patients with deep white matter lesions. Children with multiple lesions demonstrated test results in all variables 1 to 2 standard deviations below those of the control group. Conclusions Children suffering a brain injury who 1 year later are classified within the “good outcome” group according to the Glasgow Outcome Scale often have significant morphological and functional brain deficits.

CT-based response assessment of advanced gastrointestinal stromal tumor: Dual energy CT provides a more predictive imaging biomarker of clinical benefit than RECIST or Choi criteria

OBJECTIVES Dual-energy CT (DECT) allows quantification of intravenously injected iodinated contrast media in tumors, and therefore may be considered as a surrogate marker for perfusion and tumor vascularity. This study evaluated whether newly developed DECT response criteria allow better correlation with survival than established response criteria. METHODS Seventeen patients with advanced GIST treated with tyrosine-kinase-inhibitors were assessed by contrast-enhanced DECT 2 and 6 months after beginning of treatment. Response to treatment of 165 tumor lesions was evaluated according to RECIST, Choi criteria and newly developed DECT criteria, defining non-responders as an increase of both tumor size >20% and iodine related attenuation or either a >50% increase of tumor size or iodine related attenuation. All other patients were classified as responders. Progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan-Meier analysis. RESULTS Choi criteria and DECT showed a significantly longer median PFS of patients rated as responders than patients rated as non-responders (9-29 months vs. 2-6 months; p<0.02) at follow-up. Only DECT analysis at 6 months follow-up allowed a valid prediction of OS. CONCLUSION This study indicates that DECT allows a better prediction of therapeutic benefit in advanced GIST patients treated with tyrosine-kinase-inhibitors than established response criteria. However, the most important predictive biomarker of therapeutic benefit was absence of progression, no matter which response evaluation criteria were applied.

Can the Radiation Dose to CT-Enlarged but FDG-PET-Negative Inguinal Lymph Nodes in Anal Cancer Be Reduced?

Purpose:To investigate whether a dose reduction to CT-enlarged but FDG-PET-negative (([18F]-fluoro-2-deoxy-D-glucose positron emission tomography) inguinal lymph nodes in radiochemotherapy of anal cancer is safe.Patients and Methods:39 sequential patients with anal cancer (mean age 59 years [range: 37–86 years], median follow-up 26 months [range: 3–51 months]) receiving pretherapeutic FDG-PET were included. All patients were treated with combined radiochemotherapy including elective radiation of the inguinal lymph nodes with 36 Gy. In case of involvement (FDG-PET positivity defined as normalized SUV [standard uptake value] above Δ > 2.5 higher than blood pool), radiation dose was increased up to 50–54 Gy. Planning CT and PET results were compared for detectability and localization of lymph nodes. In addition, local control and freedom from metastases were analyzed regarding the lymph node status as determined by FDG-PET.Results:In the planning CTs, a total of 162 inguinal lymph nodes were detected with 16 in nine patients being suspicious. Only three of these lymph nodes in three patients were PET-positive receiving 50.4–54 Gy, whereas all other patients only received elective inguinal nodal irradiation. No recurrence in inguinal lymph nodes occurred, especially not in patients with CT-enlarged inguinal lymph nodes and elective irradiation only. Patients with PET-positive nodal disease had a higher risk of developing distant metastases (p = 0.045).Conclusion:Reduction of the irradiation dose to CT-enlarged but PET-negative inguinal lymph nodes in anal cancer seems not to result in increased failure rates.Ziel:Untersucht wurde, ob eine Reduktion der Bestrahlungsdosis auf im CT vergrößerte, aber PET-negative (Positronenemissionstomographie) inguinale Lymphknoten bei der kombinierten Radiochemotherapie des Analkarzinoms ohne Verschlechterung der Prognose möglich ist.Patienten und Methodik:39 Patienten mit Analkarzinom (median Alter 59 Jahre [37–86 Jahre]), mittlerer Nachsorgezeitraum 26 Monate [3–51 Monate]) mit einer prätherapeutischen PET-Untersuchung wurden in die Auswertung eingeschlossen (Tabelle 1). Alle Patienten erhielten eine kombinierte Radiochemotherapie einschließlich einer elektiven Bestrahlung der inguinalen Lymphknoten bis zu einer Dosis von 36 Gy, bei Befall (PET-positiv: normalisierter Uptakewert mehr als das 2,5fache höher als der gemessene Wert im Blutpool) wurde die Dosis auf 50–54 Gy aufgesättigt. Das Bestrahlungsplanungs-CT und die PET-Untersuchung wurden in Bezug auf Nachweisbarkeit und Lokalisation der Lymphknoten verglichen. Zusätzlich wurden die lokale Kontrolle und das metastasenfreie Überleben in Abhängigkeit vom im PET erhobenen Lymphknotenstatus ermittelt.Ergebnisse:In den Bestrahlungsplanungs-CTs wurden insgesamt 162 inguinale Lymphknoten detektiert; davon wurden 16 bei neun Patienten als suspekt eingestuft. Nur drei dieser suspekten inguinalen Lymphknoten bei drei Patienten waren PET-positiv und wurden mit 50,4–54 Gy bestrahlt (Abbildungen 1a und 1b), während alle anderen Patienten nur eine elektive Bestrahlung der Leisten mit 36 Gy erhielten (Tabellen 2a bis 2c). Keiner der Patienten entwickelte ein Rezidiv im Bereich der inguinalen Lymphknoten, insbesondere auch nicht die Patienten, die bei im CT vergrößerten Lymphknoten nur elektiv in den Leisten bestrahlt wurden. Patienten mit PET-positiven Lymphknoten hatten ein erhöhtes Risiko für Fernmetastasen (p = 0,045; Abbildung 2).Schlussfolgerung:Eine Reduktion der Bestrahlungsdosis bei im CT vergrößerten, aber PET-negativen inguinalen Lymphknoten scheint nicht mit einem erhöhten Rezidivrisiko einherzugehen.

CMR findings in patients with hypertrophic cardiomyopathy and atrial fibrillation

ObjectivesWe sought to evaluate the relation between atrial fibrillation (AF) and the extent of myocardial scarring together with left ventricular (LV) and atrial parameters assessed by late gadolinium-enhancement (LGE) cardiovascular magnetic resonance (CMR) in patients with hypertrophic cardiomyopathy (HCM).BackgroundAF is the most common arrhythmia in HCM. Myocardial scarring is also identified frequently in HCM. However, the impact of myocardial scarring assessed by LGE CMR on the presence of AF has not been evaluated yet.Methods87 HCM patients underwent LGE CMR, echocardiography and regular ECG recordings. LV function, volumes, myocardial thickness, left atrial (LA) volume and the extent of LGE, were assessed using CMR and correlated to AF. Additionally, the presence of diastolic dysfunction and mitral regurgitation were obtained by echocardiography and also correlated to AF.ResultsEpisodes of AF were documented in 37 patients (42%). Indexed LV volumes and mass were comparable between HCM patients with and without AF. However, indexed LA volume was significantly higher in HCM patients with AF than in HCM patients without AF (68 ± 24 ml·m-2 versus 46 ± 18 ml·m-2, p = 0.0002, respectively). The mean extent of LGE was higher in HCM patients with AF than those without AF (12.4 ± 14.5% versus 6.0 ± 8.6%, p = 0.02). When adjusting for age, gender and LV mass, LGE and indexed LA volume significantly correlated to AF (r = 0.34, p = 0.02 and r = 0.42, p < 0.001 respectively). By echocardiographic examination, LV diastolic dysfunction was evident in 35 (40%) patients. Mitral regurgitation greater than II was observed in 12 patients (14%). Multivariate analysis demonstrated that LA volume and presence of diastolic dysfunction were the only independent determinant of AF in HCM patients (p = 0.006, p = 0.01 respectively). Receiver operating characteristic curve analysis indicated good predictive performance of LA volume and LGE (AUC = 0.74 and 0.64 respectively) with respect to AF.ConclusionHCM patients with AF display significantly more LGE than HCM patients without AF. However, the extent of LGE is inferior to the LA size for predicting AF prevalence. LA dilation is the strongest determinant of AF in HCM patients, and is related to the extent of LGE in the LV, irrespective of LV mass.

Multi-parametric MRI of rectal cancer – Do quantitative functional MR measurements correlate with radiologic and pathologic tumor stages?

PURPOSE The purpose of this study is two-fold. First, to evaluate, whether functional rectal MRI techniques can be analyzed in a reproducible manner by different readers and second, to assess whether different clinical and pathologic T and N stages can be differentiated by functional MRI measurements. MATERIALS AND METHODS 54 patients (38 men, 16 female; mean age 63.2 ± 12.2 years) with pathologically proven rectal cancer were included in this retrospective IRB-approved study. All patients were referred for a multi-parametric MRI protocol on a 3 Tesla MR-system, consisting of a high-resolution, axial T2 TSE sequence, DWI and perfusion imaging (plasma flow -s PFTumor) prior to any treatment. Two experienced radiologists evaluated the MRI measurements, blinded to clinical data and outcome. Inter-reader correlation and the association of functional MRI parameters with c- and p-staging were analyzed. RESULTS The inter-reader correlation for lymph node (ρ 0.76-0.94; p<0.0002) and primary tumor (ρ 0.78-0.92; p<0.0001) apparent diffusion coefficient and plasma flow (PF) values was good to very good. PFTumor values decreased with cT stage with significant differences identified between cT2 and cT3 tumors (229 versus 107.6 ml/100ml/min; p=0.05). ADCTumor values did not differ significantly. No substantial discrepancies in lymph node ADCLn values or short axis diameter were found among cN1-3 stages, whereas PFLn values were distinct between cN1 versus cN2 stages (p=0.03). In the patients without neoadjuvant RCT no statistically significant differences in the assessed functional parameters on the basis of pathologic stage were found. CONCLUSION This study illustrates that ADC as well as MR perfusion values can be analyzed with good interobserver agreement in patients with rectal cancer. Moreover, MR perfusion parameters may allow accurate differentiation of tumor stages. Both findings suggest that functional MRI parameters may help to discriminate T and N stages for clinical decision making.