[Stroke alarm-Arterial ischemic stroke as one of the most time-critical emergencies in children and adolescents]. / Notfall-Neuropädiatrie ­ Der arteriell ischämische Schlaganfall als einer der zeitkritischsten Notfälle bei Kindern und Jugendlichen.

Arterial ischemic stroke in childhood and adolescence is one of the most time-critical emergencies in pediatrics. Nevertheless, it is often diagnosed with a considerable time delay which may be associated with low awareness, the sometimes nonspecific clinical presentation with a wide variety of differential diagnoses, and less established 'acute care structures'. The revascularisation strategies in adult stroke care are also potential and promising treatment options for children, even if available evidence is still limited. In the post-acute phase, the etiological work-up is complex due to the multitude of risk factors to be considered. But it is essential to identify each child's individual risk profile as it determines secondary prevention, risk of recurrence and outcome. Long-term care in a multiprofessional, interdisciplinary team must take into account the bio-psycho-social aspects to integrate the child into its social and educational, and later professional environment.

Robust evidence for long-term survival with 90Y radioembolization in chemorefractory liver-predominant metastatic colorectal cancer.

OBJECTIVES: Our aim was to provide further evidence for the efficacy/safety of radioembolization using yttrium-90-resin microspheres for unresectable chemorefractory liver metastases from colorectal cancer (mCRC). METHODS: We followed 104 consecutively treated patients until death. Overall survival (OS) was calculated from the day of the first radioembolization procedure. Response was defined by changes in tumour volume as defined by Response Evaluation Criteria in Solid Tumours (RECIST) v1.0 and/or a ≥30 % reduction in serum carcinoembryonic antigen (CEA) at 3 months. RESULTS: Survival varied between 23 months in patients who had a complete response to prior chemotherapy and 13 months in patients with a partial response or stable disease. Median OS also significantly improved (from 5.8 months to 17.1 months) if response durability to radioembolization extended beyond 6 months. Patients with a positive trend in CEA serum levels (≥30 % reduction) at 3 months post-radioembolization also had a survival advantage compared with those who did not: 15.0 vs 6.7 months. Radioembolization was well tolerated. Grade 3 increases in bilirubin were reported in 5.0 % of patients at 3 months postprocedure. CONCLUSIONS: After multiple chemotherapies, many patients still have a good performance status and are eligible for radioembolization. This single procedure can achieve meaningful survivals and is generally well tolerated. KEY POINTS: • After multiple chemotherapies, many patients are still eligible for radioembolization (RE). • RE can achieve meaningful survival in patients with chemorefractory liver-predominant metastatic colorectal cancer (mCRC). • Tumour responsiveness to prior systemic treatments is a significant determinant of overall survival (OS) after RE. • Radioembolization in patients with a good performance status is generally well tolerated.

Renal Pseudoaneurysms and Arteriovenous Fistulas as a Complication of Nephron-Sparing Partial Nephrectomy: Technical and Functional Outcomes of Patients Treated With Selective Microcoil Embolization During a Ten-Year Period.

PURPOSE: The aim of this study was to evaluate the clinical and functional outcomes in patients who underwent selective interventional embolization of renal pseudoaneurysms or arteriovenous fistulas at our center. MATERIALS AND METHODS: Our retrospective analysis included all consecutive patients who received selective transcatheter embolization of renal pseudoaneurysms or arteriovenous fistulas after partial nephrectomy in our department from January, 2003 to September, 2013. The technical and clinical success rate and functional outcome of every procedure was collected and analyzed. Furthermore, the change in renal parenchymal volume before and after embolization was determined in a subgroup. RESULTS: A total of 1425 patients underwent partial nephrectomy at our hospital. Of these, 39 (2.7 %) were identified with a pseudoaneurysm or an arteriovenous fistula after partial nephrectomy. The diagnosis of the vascular lesions was made by means of biphasic CT or CEUS. Technical success by means of selective microcoil embolization was achieved in all 39 patients (100 %). Clinical success, defined as no need for further operation or nephrectomy during follow-up, was achieved in 35 of 39 patients (85.7 %). Renal function, as measured by eGFR before and after the intervention, did not change significantly. However, a mean loss of parenchymal volume of 25.2 % was observed in a subgroup. No major or minor complications were attributable to the embolization procedure. CONCLUSION: Transcatheter embolization is a promising method for treating vascular complications which may occur after partial nephrectomy. We confirm the high success rate of this technique while discussing renal functional outcomes and potential safety aspects. KEY POINTS: Arterial pseudoaneurysms and arteriovenous fistulas are rare but severe complications after partial nephrectomy. Selective microcoil embolization is a safe and effective kidney-preserving procedure for treating these complications. Embolization leads to a significant loss of renal parenchymal volume but not to a loss of renal function.

Safety of Radioembolization with (90)Yttrium Resin Microspheres Depending on Coiling or No-Coiling of Aberrant/High-Risk Vessels.

PURPOSE: To evaluate the safety of radioembolization (RE) with (90)Yttrium ((90)Y) resin microspheres depending on coiling or no-coiling of aberrant/high-risk vessels. MATERIALS AND METHODS: Early and late toxicity after 566 RE procedures were analyzed retrospectively in accordance with the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE v3.0). For optimal safety, aberrant vessels were either coil embolized (n = 240/566, coiling group) or a more peripheral position of the catheter tip was chosen to treat right or left liver lobes (n = 326/566, no-coiling group). RESULTS: Clinically relevant late toxicities (≥ Grade 3) were observed in 1% of our overall cohort. The no-coiling group had significantly less "any" (P = 0.0001) or "clinically relevant" (P = 0.0003) early toxicity. There was no significant difference (P > 0.05) in delayed toxicity in the coiling versus the no-coiling group. No RE-induced liver disease was noted after all 566 procedures. CONCLUSION: RE with (90)Y resin microspheres is a safe and effective treatment option. Performing RE without coil embolization of aberrant vessels prior to treatment could be an alternative for experienced centers.

[Computed tomography guidance: fluoroscopy and more]. / CT-Steuerung: Fluoroskopie und mehr.

Although ultrasound and magnetic resonance imaging are competitive imaging modalities for the guidance of needle-based interventions, computed tomography (CT) is the only modality suitable for image-guided interventions in all regions of the body, including the lungs and bone. The ongoing technical development of CT involves accelerated image acquisition, significantly improved spatial resolution, CT scanners with an extended gantry diameter, acceleration of the procedure through joystick control of relevant functions of interventional CT by the interventional radiologist and tube current modulation to protect the hands of the examiner and radiosensitive organs of the patient. CT fluoroscopy can be used as a real-time method (the intervention is monitored under continuous CT fluoroscopy) or as a quick check method (repeated acquisitions of individual CT fluoroscopic images after each change of needle or table position). For the two approaches, multislice CT fluoroscopy (MSCTF) technique with wide detectors is particularly useful because even in the case of needle deviation from the center slice the needle tip is simultaneously visualised in the neighboring slices. With the aid of this technique a precise placement of interventional devices is possible even in angled access routes and in the presence of pronounced respiratory organ movements. As the reduction of CT fluoroscopy time significantly reduces radiation exposure for the patient and staff, the combination of a quick check technique and a low milliampere technique with multislice CT fluoroscopy devices is advantageous.

[MRI for monitoring of high intensity focused ultrasound: current developments]. / MRT zum Monitoring bei hochintensivem fokussiertem Ultraschall: Aktuelle Entwicklungen.

With respect to monitoring of high intensity focused ultrasound (HIFU), synonym focused ultrasound (FUS) treatment, magnetic resonance imaging (MRI) is characterized by several advantageous properties: the precise definition and morphological characterization of the target area (before and after the intervention), the real-time visualization of the treatment effect by thermal imaging (during the intervention) and in the sense of a stereotactic system, the 3-dimensional localization of the target lesion, planning of the target volume and assessment of the achieved ablation volume (before and during the intervention). Non-enhanced T2-weighted multislice MR images are acquired for planning of the intervention. For temperature monitoring (comprising thermometry and thermodosimetry), the temperature-dependent shift of proton resonance frequency (PRFS) is most frequently employed. This method is independent of the treated tissue type or thermally induced tissue changes and facilitates a relative measurement of the temperature change based on a reference value. Future MRI applications include diffusion-weighted MRI (DWI-MRI; for the intrainterventional estimation of treatment efficacy), dynamic contrast-enhanced MRI (DCE-MRI, for the prediction of the potential and assessment of the treatment effect achieved) and motion-corrected temperature monitoring (referenceless and multibaseline thermometry).

[MR-guided focused ultrasound. Current and future applications]. / MR-gesteuerter fokussierter Ultraschall. Aktuelle und potenzielle Indikationen.

STANDARD RADIOLOGICAL METHODS: High-intensity focused ultrasound (synonyms FUS and HIFU) under magnetic resonance imaging (MRI) guidance (synonyms MRgFUS and MR-HIFU) is a completely non-invasive technology for accurate thermal ablation of a target tissue while neighboring tissues and organs are preserved. METHODICAL INNOVATIONS: The combination of FUS with MRI for planning, (near) real-time monitoring and outcome assessment of treatment markedly enhances the safety of the procedure. ACHIEVEMENTS: The MRgFUS procedure is clinically established in particular for the treatment of symptomatic uterine fibroids, followed by palliative ablation of painful bone metastases. Furthermore, promising results have been shown for the treatment of adenomyosis, malignant tumors of the prostate, breast and liver and for various intracranial applications, such as thermal ablation of brain tumors, functional neurosurgery and transient disruption of the blood-brain barrier.

Image fusion in the management of thermal tumor ablation of the liver.

PURPOSE: The purpose of this study was to evaluate whether image fusion with contrast enhanced ultrasound (CEUS) and CT is effective in the pre-, intra- and post-interventional management of liver lesions during microwave or radiofrequency ablation. METHODS AND MATERIALS: Fifteen patients with a single hepatocellular carcinoma (HCC) up to 3 cm diameter, identified on both contrast-enhanced CT (Siemens Somatom Definition AS and Definition Edge, Siemens Healthcare, Erlangen, Germany) and ultrasound (Siemens ACUSON S2000™ or S3000™, Siemens Healthcare, Erlangen, Germany) were retrospectively enrolled between July 2011 and May 2012. Either automatic registration or plane match registration was chosen on CT and ultrasound for the pre-, intra- and postinterventional management of all treated liver lesions during microwave or radiofrequency ablation. Using conventional ultrasound B-mode, CEUS and image fusion including B-mode and CEUS the detectability of the liver lesions was evaluated semi-quantitatively by comparing the image sequences in a consensus reading. Eight patients underwent radiofrequency ablation and seven patients underwent microwave ablation. RESULTS: All patients were examined using all diagnostic ultrasound tools of the study. The results show that the procedure is easy and convenient to perform, as well as efficient. The co-registration procedure took approximately 5 to 10 minutes depending on the amount of DICOM volume-data and the habitus of the patient. The results show that the use of image fusion with CT and contrast-enhanced ultrasound could improve the diagnostic assessment capabilities in comparison to the examination without image fusion in the pre-, intra- and postinterventional management of malignant liver lesions during thermal ablation. CONCLUSION: Percutaneous thermal ablation guided by contrast-enhanced ultrasound and image fusion seems to be an efficient approach for malignant liver lesions especially if these are not clearly demarcated by B-mode. The use of the image fusion technique in the pre-, intra- and postinterventional management can increase operator confidence, the accuracy of the procedure, and technical success in real time.

Changes in normal liver and spleen volume after radioembolization with (90)Y-resin microspheres in metastatic breast cancer patients: findings and clinical significance.

PURPOSE: In clinical trials with yttrium-90-resin-microspheres for the management of colorectal cancer liver metastases, it was observed that radioembolization might result in splenomegaly and an increase in portal vein size. Subclinical hepatitis in normal liver tissue as well as the effects of radioembolization and prior chemotherapy are suspected to be responsible for this phenomenon. The purpose of this study was to quantify the changes in liver and spleen volume and portal vein diameter after radioembolization. METHODS: Twenty-seven patients with liver-dominant metastatic disease from breast cancer who had not responded to chemotherapy or had to abandon chemotherapy because of its toxic effects were evaluated. Changes in liver and spleen volume and portal vein diameter as well as liver tumor volume and diameter were quantified using computed tomography scans. RESULTS: Radioembolization was associated with a significant mean decrease in the whole liver volume of 10.2% (median 16.7%; P = 0.0024), mainly caused by a reduction in the right lobe volume (mean 16.0%; P < 0.0001). These changes were accompanied by a significant increase in the diameter of the main portal vein (mean 6.8%; P < 0.0001) as well as splenic volume (mean 50.4%; P < 0.0001). Liver-tumor volume and diameter decreased by a median of 24 and 39.7%. CONCLUSIONS: Radioembolization is an effective treatment for tumor size reduction in patients with breast cancer liver metastases. Treatment is associated with changes of hepatic parenchymal volume, splenic volume, and portal vein size that appear not to represent clinically important sequelae in this patient cohort.

Arterial therapies of non-colorectal cancer metastases to the liver (from chemoembolization to radioembolization).

Treatment of primary and secondary hepatic malignancies with transarterial chemoembolization (TACE) represents an essential component of interventional oncology known for many years and performed by many interventional radiologists first in primary liver tumors and nowadays even in metastases of different origins. Radioembolization (RE) has been introduced to the clinical arsenal of cytoreductive modalities in recent years. There is growing evidence for efficiency in liver tumors of various entities, with the most prominent ones being hepatocellular carcinoma, colorectal cancer, and neuroendocrine tumors. Hepatic metastases of other tumor entities (breast cancer, malignant melanoma, and pancreatic cancer) are treatment-sensitive. This article focuses on procedural and technical aspects for selection, preparation, and performance of treatment as well as the results in metastatic breast cancer, neuroendocrine tumors, melanoma, and pancreatic cancer giving an overview of the results after RE, transarterial embolization, or TACE.

Interdisciplinary expert consultation via a teleradiology platform--influence on therapeutic decision-making and patient referral rates to an academic tertiary care center.

In addition to teleradiological reporting as a nighthawking or a regular service, teleradiological communication can be used for interdisciplinary expert consultation. We intended to evaluate an interdisciplinary consultation system based on a teleradiology platform with regard to its impact on therapeutic decision-making, directed patient referrals to an academic tertiary care center and the economic benefit for the hospital providing the service. Therefore, consultations from five secondary care centers and consecutive admissions to an academic tertiary care center were prospectively evaluated over a time period of six months. A total of 69 interdisciplinary expert consultations were performed. In 54 % of the cases the patients were consecutively referred to the university hospital for further treatment. In all acutely life-threatening emergencies (n = 9), fast and focused treatment by referral to the academic tertiary care center was achieved (average time to treat 130 min). The admissions to the academic tertiary care center led to improved utilization of its facilities with additional revenue of more than 1,000000 euro p. a. An interdisciplinary expert consultation via a teleradiology platform enables fast and efficient expert care with improved and accelerated patient management and improved utilization of the service providing hospital.

Repercusión de un sistema de reconocimiento del habla integrado en un PACS/RIS con respecto al tiempo invertido en elaborar y poner a disposición los informes radiológicos / Impact of a PACS/RIS-integrated speech recognition system on the time expenditure in completing and making available radiology reports

Purpose: Quantification of the impact of a PACS/RIS-integrated speech recognition system (SRS) on the time expenditure for radiology reporting and on hospital-wide report availability (RA) in a university institution. Material and methods: In a prospective pilot study, the following parameters were assessed for 669 radiographic examinations (CR): 1. time requirement per report dictation (TED: dictation time (s)/number of images (examination) x number of words (report)) with either a combination of PACS/ tape-based dictation (TD: analog dictation device/ minicassette/transcription) or PACS/RIS/speech recognition system(RR: remote recognition/transcription and OR: online recognition/self-correction by radiologist), respectively, and 2. the ReportTur-naround Time (RTT) as the time interval from the entry of the first image into the PACS to the available RIS/HIS report. Two equal time periods were chosen retrospectively from the RIS database: 11/2002-2/2003 (only TD) and 11/2003-2/2004 (only RR or OR with speech recognition system (SRS)). The midterm (> 24 h, 24 h intervals) and short-term (< 24 h, 1 h intervals) RA after examination completion were calculated for all modalities and for CR, CT, MR and XA/DS separately. The relative increase in the mid-term RA (RIMRA: related to total number of examinations in each time period) and increase in the short-term RA (ISRA: ratio of available reports during the 1st to 24th hour) were calculated. Results: Prospectively there was a significant difference between TD/RR/OR (n = 151/257/261) regarding mean TED (0.44/0.54/0.62 s (per word and image)) and mean RTT.

Objetivo: Cuantificar la repercusión de un sistema de reconocimiento del habla integrado en un PACS/RIS en el tiempo invertido en los informes radiológicos y su disponibilidad en una Clínica Universitaria. Material y métodos: Estudio piloto prospectivo; en 669 radiografías se registró el tiempo invertido por dictado con cinta y sistemas PACS/RIS de reconocimiento (dictado por lotes o dictado en línea) y el Report Turnaround Time, intervalo de tiempo desde la introducción de imagen en PACS hasta tener informe disponible en RIS/CIS. En análisis retrospectivo de base de datos de RIS se estudió 11/2002-02/2003 y 11/2003-02/2004. Se calculó la media y el aumento relativo de la disponibilidad de informes a mediano y corto plazo tras la finalización del estudio. Resultados: Se observaron importantes diferencias en el tiempo invertido para cada modalidad (0,44/0,54/0,62 s por palabra e imagen) y del RTT medio (10,47/6,65/1,27 h). Se evaluaron retrospectivamente 37.898/39.680 informes de los períodos mencionados. En CR/TC, se observó un aumento medio del 20 por ciento en la disponibilidad de informes a corto plazo y en todas las modalidades fue más del triple en las primeras 24 h. En el caso de CR/TC/RM, el primer día hubo un aumento máximo de la disponibilidad a mediano plazo (factor 3,1/5,8/4,0) y en el caso de XA/DS, en el segundo día (factor 2,0). Conclusión: Cuando se utiliza un sistema de reconocimiento del habla se modifica el flujo de trabajo y se invierte inicialmente más tiempo para la elaboración de informes. Los sistemas de reconocimiento integrados en PACS/RIS mejoran considerablemente la disponibilidad de los informes a corto y mediano plazo, redundando en la calidad de la atención de los pacientes.

Quantitative 3D MR evaluation of autologous chondrocyte implantation in the knee: feasibility and initial results.

OBJECTIVE: To evaluate the feasibility of quantitative magnetic resonance imaging (MRI) based follow-up of cartilage volumetric data in patients after autologous chondrocyte implantation (ACI). To provide results from a 1-year follow-up study. METHODS: From 21 ACI patients sagittal FS 3D FLASH (50/11/30; 0.6x0.6x1.5mm(3)) MRI knee data sets were obtained pre and 1-year post-ACI surgery in the femoral condyles. After semi-automated segmentation and 3D reconstruction of the cartilage plates, cartilage volume, mean thickness and size of the cartilage-bone interface were calculated. Susceptibility artifacts were evaluated in all, intra-observer reproducibility was evaluated in six of the patients. Volumetric parameters were compared during follow-up and sensitivity to change was assessed for the total femur vs the separately evaluated medial/lateral portions of the femur. RESULTS: Reproducibility error (coefficient of variation %) was 3.9%/4.4% for the med./lat. tibial and 5.1% for the femoral cartilage volume. Susceptibility artifacts led to the exclusion of three out of the 21 patients, but were moderate in the remaining 18 patients, not preventing reproducible segmentation. In contrast to lack of significant change in the (non-operated) tibiae, a mean 6% increase of volume and thickness in the treated femora (P<0.001 Wilcoxon) relative to the pre-OP data was observed. Sensitivity to change for the femur ranged from 0.74 to 2.60 for cartilage volume and thickness and was improved when evaluating only the treated portion of the femur in contrast to the total femur. CONCLUSION: Our data indicate that despite postoperative susceptibility artifacts quantitative evaluation of cartilage volumetric parameters can be performed in ACI patients. The technique is able to describe changes of these parameters over 1 year. Volumetric follow-up may help to identify altered disease progression.

[Vertebroplasty in the treatment of back pain]. / Vertebroplastie zur Therapie des Rückenschmerzes.

BACKGROUND: Percutaneous vertebroplasty (PVP) represents a minimally invasive option which is gaining in importance for the treatment of vertebral compression fractures (VCF) and osteolysis of the spine. This article describes the indications for its use, peri-interventional imaging, technique, and results of PVP. MATERIAL AND METHODS: The current guidelines for performance of PVP are explained in accordance with the "Interdisciplinary Consensus Paper on Vertebroplasty and Kyphoplasty" of the German Professional Associations and the 2005 CIRSE Guidelines. The results of our own study carried out in 2002 are compared to the complication rates and clinical outcomes reported in the literature. RESULTS: Painful osteoporotic VCF and osteolysis within the vertebral body due to metastases and multiple myeloma are indications for PVP. Absolute contraindications are, in particular, asymptomatic VCF, alleviation of pain by drug treatment, therapy-refractory coagulopathies, allergies to cement components, and active infections. MRI or CT is indicated before undertaking PVP to assess the fracture age, to exclude other causes of pain, and to evaluate the posterior edge of the vertebral body. High-quality mono- or biplanar fluoroscopy--preferably in combination with CT (fluoroscopy)--is necessary for PVP to minimize the risk of cement leakage. A clear reduction in pain [mean reduction of 6.1 points (VAS)] is achieved in 86-92% of the patients with PVP. Our own study treating 58 patients (mean follow-up 323+/-99 days) revealed a clear alleviation of pain in 77% [-5.7 points (VAS)]. CONCLUSION: PVP constitutes a safe and effective minimally invasive treatment approach to stabilize and reduce acute and chronic back pain due to osteoporotic VCF and tumor-associated osteolysis.

[Impact of a PACS/RIS-integrated speech recognition system on radiology reporting time and report availability]. / Einfluss eines PACS-/RIS-integrierten Spracherkennungssystems auf den Zeitaufwand der Erstellung und die Verfügbarkeit radiologischer Befunde.

PURPOSE: Quantification of the impact of a PACS/RIS-integrated speech recognition system (SRS) on the time expenditure for radiology reporting and on hospital-wide report availability (RA) in a university institution. MATERIAL AND METHODS: In a prospective pilot study, the following parameters were assessed for 669 radiographic examinations (CR): 1. time requirement per report dictation (TED: dictation time (s)/number of images [examination] x number of words [report]) with either a combination of PACS/tape-based dictation (TD: analog dictation device/mini-cassette/transcription) or PACS/RIS/speech recognition system (RR: remote recognition/transcription and OR: online recognition/self-correction by radiologist), respectively, and 2. the Report Turnaround Time (RTT) as the time interval from the entry of the first image into the PACS to the available RIS/HIS report. Two equal time periods were chosen retrospectively from the RIS database: 11/2002 - 2/2003 (only TD) and 11/2003 - 2/2004 (only RR or OR with speech recognition system [SRS]). The mid-term (> or = 24 h, 24 h intervals) and short-term (< 24 h, 1 h intervals) RA after examination completion were calculated for all modalities and for CR, CT, MR and XA/DS separately. The relative increase in the mid-term RA (RIMRA: related to total number of examinations in each time period) and increase in the short-term RA (ISRA: ratio of available reports during the 1st to 24th hour) were calculated. RESULTS: Prospectively, there was a significant difference between TD/RR/OR (n = 151/257/261) regarding mean TED (0.44/0.54/0.62 s [per word and image]) and mean RTT (10.47/6.65/1.27 h), respectively. Retrospectively, 37 898/39 680 reports were computed from the RIS database for the time periods of 11/2002 - 2/2003 and 11/2003 - 2/2004. For CR/CT there was a shift of the short-term RA to the first 6 hours after examination completion (mean cumulative RA 20 % higher) with a more than three-fold increase in the total number of available reports within 24 hours (all modalities). The RIMRA for CR/CT/MR was 3.1/5.8/4.0 in the first 24 hours, and 2.0 for XA/DS in the second 24-hour interval. CONCLUSION: In comparison to tape-based dictation, an SRS results in a significantly higher primary time expenditure and a modified report dictation workflow. In a university institution, a PACS/RIS-integrated SRS achieves a marked improvement in both short- and mid-term RA which eventually results in an improvement in patient care.