Application of liver-specific contrast agents for evaluation of focal liver lesions - Expert recommendations from the Gastrointestinal and Abdominal Imaging Workgroup of the German Roentgen Society. / Einsatz leberspezifischer Kontrastmittel in der MRT zur Beurteilung von Leberläsionen ­ Expertenempfehlungen der AG Gastrointestinal- und Abdominaldiagnostik der Deutschen Röntgengesellschaft.

PURPOSE: Contrast-enhanced MRI is the imaging modality of choice for the detection and differential diagnosis of focal liver lesions. Liver-specific contrast agents (CAs) are now well established in addition to extracellular contrast agents. However, there is a lack of explicit recommendations reflecting the pros and cons of each specific contrast agent in the daily routine. MATERIALS AND METHODS: Development of recommendations for the clinical application of liver-specific CAs by members of the Gastrointestinal and Abdominal Imaging Workgroup within the Germany Radiological Society, using methodology comparable to that of an S1 guideline with informal consensus. The diagnostic criteria for the evaluation of liver lesions are intentionally outside the scope of this article, as there are already plenty of excellent publications available. RESULTS AND CONCLUSION: The application of liver-specific CAs in the daily routine is associated with advantages and disadvantages due to the specific pharmacokinetic and pharmacodynamic properties and necessitates adjustment of the imaging technique as well consideration during image interpretation. Recommendations for the application of liver-specific CAs are presented based on different clinical scenarios, taking into account current evidence and guidelines. KEY POINTS: · Both liver-specific and extracellular contrast agents are established. · Liver-specific contrast agents make it possible to draw conclusions about the hepatocellular function of a lesion. · Recommendations for the use of liver-specific contrast agents in the daily routine are presented. CITATION FORMAT: · Ringe KI, Fischbach F, Grenacher L et al. Einsatz leberspezifischer Kontrastmittel in der MRT zur Beurteilung von Leberläsionen - Expertenempfehlungen der AG Gastrointestinal- und Abdominaldiagnostik der Deutschen Röntgengesellschaft. Fortschr Röntgenstr 2023; DOI: 10.1055/a-2192-9921.

Feasibility of MRI targeted single fraction HDR brachytherapy for localized prostate carcinoma: ProFocAL-study.

PURPOSE: A potential method for focal therapy in locally advanced prostate cancer is focal brachytherapy (F-BT). The purpose of this research was to evaluate midterm F-BT oncologic, functional, and toxicological results in men who had therapy for prostate cancer. MATERIALS AND METHODS: Between 2016 and 2020, F-BT was used to treat 37 patients with low- to intermediate-risk prostate cancer. The recommended dosage was 20 Gy. Failure was defined as the existence of any prostate cancer that has persisted in-field after treatment. The F-BT oncologic and functional outcomes served as the main and secondary objectives, respectively. RESULTS: A median 20-month follow-up (range 14-48 months). 37 patients received F-BT and enrolled in the study; no patient experienced a biochemical recurrence in the first 24 months, according to Phoenix criteria. In the control biopsies, only 6 patients showed in-field failure. The median initial IPSS was 6.5, at 6 months was 6.0, and at 24 months was 5.0. When the median ICIQ-SF score was 0 at the baseline, it remained 0 at 6-, 12-, and 24 months. Overall survival and biochemical disease-free survival after 3 years were all at 100% and 86.4%, respectively. There was no notable acute gastro-intestinal (GI) or genitourinary (GU) adverse effects. No intraoperative or perioperative complications occurred. CONCLUSIONS: For selected patients with low- or intermediate-risk localized prostate cancer, F-BT is a safe and effective therapy.

MRI-based fat quantification of the liver: Is it time for commercially available products?

PURPOSE: (1) To assess the clinical applicability of commercially available solutions for MR-based quantification of the hepatic fat fraction (HFF) and (2) to compare their results with clinically established in-phase/oppose-phase (IP/OP) imaging as proposed by Dixon. METHODS: Twenty-eight patients underwent MRI examinations using multigradient-echo sequences including multi-peak modeling and T2∗ correction, IP/OP imaging and multi-echo spectroscopy with successive HFF evaluation. Histopathological examination yielded the fraction of adipose hepatocytes (fAH) and the presence of increased liver iron concentration (LIC). We correlated HFF with fAH, and assessed concordance correlations among the MR-based methods with the presence of increased LIC as a control parameter. We investigated the liver segmentation quality and overall workflow of the postprocessing solutions (Philips LiverHealth and Siemens LiverLab). RESULTS: IP/OP imaging yielded a very strong correlation (r=0.88) with fAH when excluding three cases with increased LIC. Multigradient echo imaging and multiecho spectroscopy quantifications yielded similar correlations (r=0.87…0.93) as IP/OP imaging but were insensitive to increased LIC. Visceral fat, kidney tissue and major vessels were included regularly in the segmentation. Spectroscopic fat quantification was sensitive to the inclusion of visceral fat. CONCLUSIONS: IP/OP imaging allows HFF quantification when ruling out hepatic siderosis, whereas dedicated multi-echo imaging sequences and spectroscopy show no bias for increased iron concentration. The segmentation quality and workflow of both postprocessing solutions need to be improved. Nevertheless, all solutions are able to bring MRI-based hepatic fat quantification into the clinical application. We therefore recommend commercial hepatic fat quantification tools for institutions specialised to abdominal imaging.

Diffusion-Weighted Imaging Reflects Tumor Grading and Microvascular Invasion in Hepatocellular Carcinoma.

BACKGROUND: To date, there are inconsistent data about relationships between diffusion-weighted imaging (DWI) and tumor grading/microvascular invasion (MVI) in hepatocellular carcinoma (HCC). Our purpose was to systematize the reported results regarding the role of DWI in prediction of tumor grading/MVI in HCC. METHOD: MEDLINE library, Scopus, and Embase data bases were screened up to December 2019. Overall, 29 studies with 2,715 tumors were included into the analysis. There were 20 studies regarding DWI and tumor grading, 8 studies about DWI and MVI, and 1 study investigated DWI, tumor grading, and MVI in HCC. RESULTS: In 21 studies (1,799 tumors), mean apparent diffusion coefficient (ADC) values (ADCmean) were used for distinguishing HCCs. ADCmean of G1-3 lesions overlapped significantly. In 4 studies (461 lesions), minimum ADC (ADCmin) was used. ADCmin values in G1/2 lesions were over 0.80 × 10-3 mm2/s and in G3 tumors below 0.80 × 10-3 mm2/s. In 4 studies (241 tumors), true diffusion (D) was reported. A significant overlapping of D values between G1, G2, and G3 groups was found. ADCmean and MVI were analyzed in 9 studies (1,059 HCCs). ADCmean values of MIV+/MVI- lesions overlapped significantly. ADCmin was used in 4 studies (672 lesions). ADCmin values of MVI+ tumors were in the area under 1.00 × 10-3 mm2/s. In 3 studies (227 tumors), D was used. Also, D values of MVI+ lesions were predominantly in the area under 1.00 × 10-3 mm2/s. CONCLUSION: ADCmin reflects tumor grading, and ADCmin and D predict MVI in HCC. Therefore, these DWI parameters should be estimated for every HCC lesion for pretreatment tumor stratification. ADCmean cannot predict tumor grading/MVI in HCC.

Respiratory motion artefacts in Gd-EOB-DTPA (Primovist/Eovist) and Gd-DOTA (Dotarem)-enhanced dynamic phase liver MRI after intensified and standard pre-scan patient preparation: A bi-institutional analysis.

OBJECTIVE: The objective of this study is to evaluate if intensified pre-scan patient preparation (IPPP) that comprises custom-made educational material on dynamic phase imaging and supervised pre-imaging breath-hold training in addition to standard informative conversation with verbal explanation of breath-hold commands (standard pre-scan patient preparation-SPPP) might reduce the incidence of gadoxetate disodium (Gd-EOB-DTPA)-related transient severe respiratory motion (TSM) and severity of respiratory motion (RM) during dynamic phase liver MRI. MATERIAL AND METHODS: In this bi-institutional study 100 and 110 patients who received Gd-EOB-DTPA for dynamic phase liver MRI were allocated to either IPPP or SPPP at site A and B. The control group comprised 202 patients who received gadoterate meglumine (Gd-DOTA) of which each 101 patients were allocated to IPPP or SPPP at site B. RM artefacts were scored retrospectively in dynamic phase images (1: none- 5: extensive) by five and two blinded readers at site A and B, respectively, and in the hepatobiliary phase of the Gd-EOB-DTPA-enhanced scans by two blinded readers at either site. RESULTS: The incidence of TSM was 15% at site A and 22.7% at site B (p = 0.157). IPPP did not reduce the incidence of TSM in comparison to SPPP: 16.7% vs. 21.6% (p = 0.366). This finding was consistent at site A: 12% vs. 18% (p = 0.401) and site B: 20.6% vs. 25% (p = 0.590). The TSM incidence in patients with IPPP and SPPP did not differ significantly between both sites (p = 0.227; p = 0.390). IPPP did not significantly mitigate RM in comparison to SPPP in any of the Gd-EOB-DTPA-enhanced dynamic phases and the hepatobiliary phase in patients without TSM (all p≥0.072). In the Gd-DOTA control group on the other hand, IPPP significantly mitigated RM in all dynamic phases in comparison to SPPP (all p≤0.031). CONCLUSIONS: We conclude that Gd-EOB-DTPA-related TSM cannot be mitigated by education and training and that Gd-EOB-DTPA-related breath-hold difficulty does not only affect the subgroup of patients with TSM or exclusively the arterial phase as previously proposed.

Transarterial embolization of acute iatrogenic hemorrhages: predictive factors for mortality and outcome.

OBJECTIVE: Iatrogenic hemorrhages occur in 0.5-16% of medical procedures. A retrospective study was conducted to analyze technical and clinical outcome of transarterial embolization (TAE) used for acute iatrogenic hemorrhage and to identify factors predicting outcome. METHODS: All patients undergoing TAE for acute iatrogenic bleeding from 2006 to 2013 were retrospectively analyzed. Primary end points were technical and clinical success or failure and 30 day mortality. RESULTS: A total of 153 patients underwent 182 TAEs. Factors associated with clinical failure were lower blood hemoglobin concentration, use of higher number of units of red blood cell concentrate, TAE performed at night or weekend, embolization of more than one vessel, shock state before digital subtraction angiography (DSA), and intensive care before TAE. In multivariate analysis, independent factors for clinical success were hemoglobin concentration, number of units of red blood cell concentrate, and TAE of more than one vessel. Technical failure was associated with female gender, failure to detect signs of bleeding in DSA, TAE of more than one vessel, and shock state before DSA. Bleeding related to anticoagulation medication resulted in a significantly higher mortality rate compared with bleeding due to the remaining causes (30% vs 15%, p < 0.05). CONCLUSION: Despite excellent technical success, the mortality rate was significant. The only factors affecting clinical success were bleeding intensity and extent of injury. Bleeding attributed to anticoagulation is related to high mortality and therefore requires special attention. ADVANCES IN KNOWLEDGE: This study gives insights into morbidity and mortality of iatrogenic bleedings and the technical and clinical success rates of TAE in a large study population.

MRI targeted single fraction HDR Brachytherapy for localized Prostate Carcinoma: a feasibility study of focal radiation therapy (ProFocAL).

OBJECTIVES: The aim of the study was to establish the setup and workflow for delivering focal MRI-guided high-dose-rate (HDR) brachytherapy for prostate cancer (PCA) and to assess patient comfort and safety aspects of MRI-guided single-fraction HDR. METHODS: Patients with histologically proven focal low- to intermediate-risk PCA with a single PIRADS 4/5 lesion were treated with percutaneous interstitial HDR brachytherapy in a single fraction with a minimum dose for the gross tumor volume of 20 Gy while sparing the organ at risk (OAR). Using a 3T-MRI, brachytherapy catheters were placed transgluteal in freehand technique. No antibiotic therapy or general analgesics were administered. Patient data, procedure time, patient discomfort, and complications were recorded. Quarterly PSA controls, biannual follow-up imaging, and annual re-biopsy were planned. RESULTS: So far, 9 patients were successfully treated and followed for 6 months. Mean intervention time was 34 min. Using the VAS scale, the pain reported for the intervention ranged from 2 to 3. Short-term follow-up showed no acute genitourinary or gastrointestinal toxicity so far. None of the patients displayed signs of infection. PSA levels in all patients decreased significantly. On follow up no residual PCA was detected treated region so far. PSA levels in all patients decreased significantly. On follow-up, no residual PCA was detected so far. CONCLUSIONS: MR-guided single-fraction focal HDR brachytherapy for localized PCA is feasible as well as safe for the individual patient. Catheters can be placed accurately and maximum therapeutic dose distribution can be restricted to the tumor. Countersigning the minimally invasive character of the procedure, no general anesthesia or antibiosis is necessary. KEY POINTS: • MR-guided focal HDR brachytherapy allows an accurate placement of catheters with maximum therapeutic dose distribution restricted to the tumor. • No major anesthesia or antibiosis is necessary emphasizing the minimal invasive character of the procedure. • Patients with low- and intermediate-risk prostate carcinoma in particular may benefit to halt disease progression whereas treatment-related morbidity is reduced compared with radical therapy.

Transarterial embolisation for the treatment of acute gynecological cancer bleeding.

PURPOSE: Acute bleeding in patients with gynecological cancer may result in serious life-threatening complications. In these situations, immediate diagnostic and appropriate treatment is a challenge for attending physicians. Accordingly, transarterial embolisation (TAE) has been described as an increasing and effective treatment alternative to surgery and radiotherapy. METHODS: In the present retrospective study, 25 patients were included who underwent a TAE in the period from January 2006 to June 2013 due to acute gynecological cancer bleeding. The objective of this study was to assess the efficiency and outcome of TAE. RESULTS: The primary technical success rate was 92.0% (n = 23). 21 patients were analyzed in the 30-day follow-up. The clinical success rate was achieved in 90.5% (n = 19). A clinical failure due to rebleeding was observed in 9.5% (n = 2). No associations were revealed between rebleeding and technical/clinical factors. Within 30 days after the last TAE, the complication and mortality rates were 0.0% and 5.0% (n = 1), respectively. CONCLUSION: TAE was found as an effective and safe treatment in the clinical setting of acute gynecological cancer bleeding. An important component of efficient management is an early and interdisciplinary care. Optimal treatment can be achieved by close cooperation between gynecologists, radiotherapists and interventional radiologists.

Magnetic resonance-guided direct shoulder arthrography for the detection of superior labrum anterior-posterior lesions using an open 1.0-T MRI scanner.

PURPOSE: Direct magnetic resonance arthrography (MRA) offers increased diagnostic accuracy compared to conventional magnetic resonance imaging (MRI) in the detection of superior labrum anterior-posterior (SLAP) lesions. The aim of the present study was to present the technique of magnetic resonance-guided direct shoulder arthrography (MDSA), to evaluate the diagnostic value of this novel MRA procedure to detect SLAP lesions in comparison to the currently practiced MRI, and to correlate the radiological findings to the respective arthroscopic findings. MATERIAL AND METHODS: Fifty-six patients with clinical signs of a SLAP lesion underwent both MRI examination and MDSA prior to arthroscopic surgery. The MRI of both interventions were compared with the arthroscopic findings. Statistical analysis was performed using the McNemar test. RESULTS: Sensitivity, specificity, and accuracy for detecting SLAP lesions were 23%, 88%, and 54% on MRI and 80%, 81%, and 80% on MDSA, respectively. Sensitivity (p < 0.001) and accuracy (p = 0.001) in detection of SLAP lesions were significantly higher by MDSA whereas accuracy showed no significant differences (p = 0.625). CONCLUSIONS: The MDSA can be performed in an open 1.0-T MRI scanner with a high level of technical success and a reasonable methodical effort. The modification of MRA provides the requirements as a practicable routine shoulder magnetic resonance examination including arthrography to detect SLAP lesions. The diagnostic value is significantly better than MRI examinations without included arthrography, which currently predominates the clinical practice to investigate shoulder pathology.

Transcatheter arterial embolization of acute bleeding as 24/7 service: predictors of outcome and mortality.

OBJECTIVE: To analyze times of occurrence and identify risk factors (RFs) for technical and clinical failure and mortality of transcatheter arterial embolization (TAE) of acute bleeding in a major hospital. METHODS: All TAEs performed at our hospital from 2006 to 2013 (n = 327) were retrospectively analyzed. RESULTS: TAEs were performed during regular weekday hours in 165 (50%) and during off-hours in 162 (50%) cases. With 40 regular and 128 off-hours/week, 3.25 times more TAEs were performed during regular hours. There was an even distribution across weekdays (Mon-Fri:16.9 ± 1.5%), while fewer TAEs were performed on weekends (Sat: 8.3%, Sun: 7.3%). Technical success of TAEs was 93.9% with a clinical success of 79.2% and a 30-day mortality of 18.4%. Shock was an RF for technical failure (p = 0.022). RFs for clinical failure were low hemoglobin (Hb) (p = 0.021) and transfusion of ≥6 units packed cells (p = 0.009). Independent RFs for mortality were clinical failure (p < 0.001), coagulopathy (p = 0.005), and shock (p < 0.001). CONCLUSION: Our results provide no evidence for a subjectively perceived increase in TAEs during off-hours but rather appear to show that most TAEs are performed during regular hours. Prompt TAE to control acute bleeding is crucial to prevent a drop in Hb with shock and the need for transfusion, which may promote coagulopathy and rebleeding, all of which are risk factors for a negative outcome. ADVANCES IN KNOWLEDGE: The presented analysis provides insights of occurrences and risk factors for success of transcatheter arterial embolization in acute bleeding in a large study population.

Assessment of Low-Grade Meniscal and Cartilage Damage of the Knee at 7 T: A Comparison to 3 T Imaging With Arthroscopic Correlation.

OBJECTIVES: The aim of this study was to compare the assessment of low-grade meniscal tears and cartilage damage in ultrahigh-field magnetic resonance imaging (MRI) at 7 T to routine clinical MRI at 3 T. MATERIALS AND METHODS: This study was approved by the local ethics committee, and written informed consent was obtained from each patient. Forty-one patients with suspected meniscal damage or mild osteoarthritis (Kellgren-Lawrence score, 0-2) received 7 T as well as routine clinical 3 T consecutively. The imaging protocol at both field strengths consisted of PD-weighted imaging with more than doubled resolution at 7 T. Images were read blinded regarding field strength and patient characteristics by 3 readers with different experience in musculoskeletal MRI (3 years, 6 years, and 10 years) according to a modified whole-organ MRI score of the knee in osteoarthritis and the Score of the International Cartilage Repair Society. Arthroscopic reports as a criterion standard were available for 12 patients. A multifactorial mixed model analysis was performed. RESULTS: The mean cumulated diagnostic score at 7 T was significantly closer to the criterion standard compared with 3 T in patients where criterion standard was available (P < 0.001). In all 41 patients, the damages were rated more severely at 7 T reflected by a mean higher cumulative score in cartilage (P < 0.001) and in the meniscus (P < 0.001). No difference in interreader variability between 3 T and 7 T was observed. Imaging acquisition time was nearly identical. CONCLUSIONS: Morphologic imaging of cartilage and meniscal damage of the knee in ultrahigh-field MRI at 7 T with PD-weighted TSE sequences seemed to have a significantly higher diagnostic accuracy than 3 T and can be performed with equal acquisition times while exploiting higher resolution of 7 T.

Initial Assessment of the Efficacy of Irreversible Electroporation in the Focal Treatment of Localized Renal Cell Carcinoma With Delayed-interval Kidney Tumor Resection (Irreversible Electroporation of Kidney Tumors Before Partial Nephrectomy [IRENE] Trial-An Ablate-and-Resect Pilot Study).

OBJECTIVE: To assess the efficacy of irreversible electroporation (IRE) ablation of pT1a renal cell carcinoma (RCC) in the first prospective, monocentric phase 2a pilot ablate-and-resect study (Irreversible Electroporation of Kidney Tumors Before Partial Nephrectomy [IRENE] trial). It has been postulated that focal IRE can bring about complete ablation of soft-tissue tumors with protection of healthy peritumoral tissue and anatomic structures. PATIENTS AND METHODS: The first 7 study patients with biopsy-proven pT1a RCC (15-39 mm) underwent IRE. Percutaneous computed tomography-guided IRE was performed with electrocardiographic triggering under general anesthesia and deep muscle paralysis with 3-6 monopolar electrodes positioned within the renal tumor. Twenty-eight days later, the tumor region was completely resected to confirm tumor destruction pathologically. Individual results for these patients are displayed, described, and discussed. RESULTS: Technical feasibility was attained in all patients, but electrode placement and ablation were complex, with a mean overall procedure time of 129 minutes. There were no major complications. Partial kidney resection was performed in 5 patients, and radical nephrectomy was performed in 2 patients because of central tumor location and ablation areas. Resections revealed by tumor, node, and metastasis classification of the International Union for Cancer Control 2017 no residual tumor as complete ablation in 4 cases (ypT0V0N0Pn0R0) and microscopic residual tumor cells as incomplete ablation in the other 3 cases (ypT1aV0N0Pn0R1). CONCLUSION: Renal percutaneous IRE appears to be a safe treatment for pT1a RCC but requires substantial procedural effort. Resection specimens of the ablation zone revealed a high rate of microscopic incomplete ablation 4 weeks after IRE. According to these initial study results, curative, kidney-sparing ablation of T1a RCC appears possible but needs technical improvement to ensure complete ablation.

Feasibility study of MR-guided transgluteal targeted in-bore biopsy for suspicious lesions of the prostate at 3 Tesla using a freehand approach.

OBJECTIVE: The aim of our study was (1) to establish an in-bore targeted biopsy of suspicious prostate lesions, avoiding bowel penetration using a transgluteal approach and (2) to assess operator setup, patient comfort and safety aspects in the clinical setting for freehand real-time MR-guidance established for percutaneous procedures in an open MR-scanner. MATERIAL AND METHODS: 30 patients with suspect prostate lesions were biopsied in a cylindrical 3T-MRI system using a transgluteal approach in freehand technique. One to three biopsies were sampled using continuous dynamic imaging. Size, location and visibility of the lesion, intervention time, needle artefact size, interventional complications and histopathological diagnosis were recorded. RESULTS: All biopsies were technically successful. Nineteen patients showed evidence of prostate carcinoma. Cancer detection rate was 50 % in patients with previously negative TRUS-biopsy. The average intervention time was 26 min including a learning curve as the time was 13 min by the end of the study. No antibiotic prophylaxis was performed as none of the patients showed signs of infection. CONCLUSIONS: MR-guided targeted freehand biopsies of prostate lesions using a transgluteal approach are both technically feasible and time efficient in a standard closed-bore 3T-MR scanner as well as safe for the individual patient. KEY POINTS: • Open-bore freehand interventional principles were adapted to closed-bore systems. • Prostate MR-guided freehand biopsies were feasible in a clinical setting. • A transgluteal approach provides a short and simplified work flow. • An inoculation of the prostate with bowel flora is avoided. • The intervention time is comparable to the stereotactic approach.

Angiographic Anatomy and Relevance of 3 and 9 O'clock Arteries During Radioembolization.

PURPOSE: 3 and 9 o'clock arteries (3&9As) which supply the common hepatic duct connect hepatic with duodenal/pancreatic territories. The study purpose is to describe the angiographic anatomy of 3&9As and discuss their relevance when performing radioembolization (RE) of liver malignancies. MATERIALS AND METHODS: The anatomy of the 3&9As was systematically investigated by a retrospective analysis of angiograms, technetium Tc-99 m-macroaggregated albumin (MAA) scintigrams, yttrium-90 (Y90) Bremsstrahlung-SPECT/CT datasets, and clinical data of 153 patients who underwent RE between 2010 and 2013. RESULTS: Analysis of preprocedural angiograms identified 3&9As in 36 (24%) of the 153 patients. Following embolization of the gastroduodenal artery, 3&9As were seen in 53 cases (35%). The three most common origins of the 3&9As were the right hepatic artery (n = 14), the cystic artery (n = 11), and S5 and S6 segmental arteries (n = 5 each). Extrahepatic Tc-99 m-MAA deposition in the territory of the 3&9As was significantly more frequent when 3&9As were detectable on preprocedural angiograms (28%visible vs. 11%not visible; p = 0.001) and especially when the 3&9As were not embolized or bridged prior to RE (50%not occluded/bridged vs. 19%occupied/bridged; p = 0.043). The presence of extrahepatic Y90 Bremsstrahlung after RE (n = 17) was attributable to microsphere diversion via the 3&9A territory in four patients and possible diversion via this territory in nine patients. Five of these 13 patients presented with epigastric pain, nausea, or vomiting (CTCAE severity grade ≤ 3) (p = 0.014). CONCLUSION: 3&9As are commonly detectable during evaluation angiography prior to RE, have a variable angioanatomic origin, and should be prophylactically occluded to prevent complications.

[Unclear Abdominal Pain - Not Always a Gastroenterological Emergency]. / Der unklare Bauchschmerz ­ nicht immer ein gastroenterologischer Notfall.

History and admission findings An 84-year old patient with persistent atrial fibrillation and chronic renal failure received a subcutaneous injection with low molecular weight heparin (LMWH) during a hospital stay. Over the course of her hospitalization, the patient developed abdominal pain. There was a marked hematoma at the injection site. A large tumor was palpable in the right abdominal quadrant. Examinations Due to the significant reduction in hemoglobin, we performed a CT-angiogram of the abdomen. Diagnosis We were able to visualize an intramuscular hematoma within the rectus abdominis muscle. Therapy and clinical course After visualization with digital subtraction angiography and application of microcoils and histoacryl-glue, we were able to stop bleeding. After implantation of left atrial appendage occluder, oral anticoagulation therapy could be stopped. Conclusion LMWH-treated patients with nonspecific abdominal pain should be meticulously examined to exclude iatrogenic abdominal muscle hematoma.

Hybrid Approach for Biliary Interventions Employing MRI-Guided Bile Duct Puncture with Near-Real-Time Imaging.

OBJECTIVE: To assess the feasibility of a hybrid approach employing MRI-guided bile duct (BD) puncture for subsequent fluoroscopy-guided biliary interventions in patients with non-dilated (≤3 mm) or dilated BD (≥3 mm) but unfavorable conditions for ultrasonography (US)-guided BD puncture. METHODS: A total of 23 hybrid interventions were performed in 21 patients. Visualization of BD and puncture needles (PN) in the interventional MR images was rated on a 5-point Likert scale by two radiologists. Technical success, planning time, BD puncture time and positioning adjustments of the PN as well as technical success of the biliary intervention and complication rate were recorded. RESULTS: Visualization even of third-order non-dilated BD and PN was rated excellent by both radiologists with good to excellent interrater agreement. MRI-guided BD puncture was successful in all cases. Planning and BD puncture times were 1:36 ± 2.13 (0:16-11:07) min. and 3:58 ± 2:35 (1:11-9:32) min. Positioning adjustments of the PN was necessary in two patients. Repeated capsular puncture was not necessary in any case. All biliary interventions were completed successfully without major complications. CONCLUSION: A hybrid approach which employs MRI-guided BD puncture for subsequent fluoroscopy-guided biliary intervention is feasible in clinical routine and yields high technical success in patients with non-dilated BD and/or unfavorable conditions for US-guided puncture. Excellent visualization of BD and PN in near-real-time interventional MRI allows successful cannulation of the BD.

Freehand direct arthrography of the shoulder using near real-time guidance in an open 1.0-T MRI scanner.

OBJECTIVE: To assess the technical success and duration of magnetic resonance imaging (MRI)-guided freehand direct shoulder arthrography (FDSA) with near real-time imaging implemented in a routine shoulder MRI examination on an open 1.0-T MRI scanner, and to assess the learning curve of residents new to this technique. METHODS: An experienced MRI interventionalist (the expert) performed 125 MRI-guided FDSA procedures, and 75 patients were treated by one of three residents without previous experience in MRI-guided FDSA. Technical success rate and duration of MRI-guided FDSA of the expert and the residents were compared. The residents' learning curves were assessed. The occurrence of extra-articular deposition and leakage of contrast media from the puncture site and the subsequent impairment of image interpretation were retrospectively analyzed. RESULTS: Overall technical success was 97.5 %. The expert needed overall fewer puncture needle readjustments and was faster at puncture needle positioning (p < 0.01). The learning curve of the residents, however, was steep. They leveled with the performance of the expert after ≈ 15 interventions. With a minimal amount of training all steps of MRI-guided FDSA can be performed in ≤10 min. CONCLUSION: Magnetic resonance-guided FDSA in an open 1.0-T MRI scanner can be performed with high technical success in a reasonably short amount of time. Only a short learning curve is necessary to achieve expert level.

Haemorrhagic Complications and Symptomatic Venous Thromboembolism in Interventional Tumour Ablations: The Impact of Peri-interventional Thrombosis Prophylaxis.

AIM: The aim of this study was to assess the rates of haemorrhagic and thrombotic complications in patients undergoing interventional tumour ablation with and without peri-interventional low-molecular-weight heparin (LMWH) thrombosis prophylaxis. METHODS: Patients presented with primary and secondary neoplastic lesions in the liver, lung, kidney, lymph nodes and other locations. A total of 781 tumour ablations (radiofrequency ablation, n = 112; interstitial brachytherapy, n = 669) were performed in 446 patients over 22 months; 260 were conducted under peri-interventional thrombosis prophylaxis with LMWH (H-group;) and 521 without this (NH-group, in 143 of these, LMWH was given post-interventionally). RESULTS: Sixty-three bleeding events occurred. There were significantly more bleedings in the H-group than in the NH-group (all interventions, 11.66 and 6.26 %, p = 0.0127; liver ablations, 12.73 and 7.1 %, p = 0.0416). The rate of bleeding events Grade ≥ III in all procedures was greater by a factor of >2.6 in the H-group than in the NH-group (4.64 and 1.73 %, p = 0.0243). In liver tumour ablations, the corresponding factor was about 3.3 (5.23 and 1.54 %, p = 0.028). In uni- and multivariate analyses including covariates, the only factor constantly and significantly associated with the rate of haemorrhage events was peri-interventional LMWH prophylaxis. Only one symptomatic lung embolism occurred in the entire cohort (NH-group). The 30- and 90-day mortalities were significantly greater in the H-group than in the NH-group. CONCLUSIONS: Peri-interventional LMWH thrombosis prophylaxis should be considered with caution. The rate of clinically relevant thrombotic events was extremely low.

Radioablation of liver malignancies with interstitial high-dose-rate brachytherapy : Complications and risk factors.

BACKGROUND: To evaluate complications and identify risk factors for adverse events in patients undergoing high-dose-rate interstitial brachytherapy (iBT). MATERIAL AND METHODS: Data from 192 patients treated in 343 CT- or MRI-guided interventions from 2006-2009 at our institution were analyzed. In 41 %, the largest tumor treated was ≥ 5 cm, 6 % of the patients had tumors ≥ 10 cm. Prior to iBT, 60 % of the patients had chemotherapy, 22 % liver resection, 19 % thermoablation or transarterial chemoembolization (TACE). Safety was the primary endpoint; survival data were obtained as the secondary endpoints. During follow-up, MRI or CT imaging was performed and clinical and laboratory parameters were obtained. RESULTS: The rate of major complications was below 5 %. Five major bleedings (1.5 %) occurred. The frequency of severe bleeding was significantly higher in patients with advanced liver cirrhosis. One patient developed signs of a nonclassic radiation-induced liver disease. In 3 patients, symptomatic gastrointestinal (GI) ulcers were detected. A dose exposure to the GI wall above 14 Gy/ml was a reliable threshold to predict ulcer formation. A combination of C-reactive protein ≥ 165 mg/l and/or leukocyte count ≥ 12.7 Gpt/l on the second day after the intervention predicted infection (sensitivity 90.0 %; specificity 92.8 %.) Two patients (0.6 %) died within 30 days. Median overall survival after the first liver treatment was 20.1 months for all patients and the local recurrence-free surviving proportion was 89 % after 12 months. CONCLUSIONS: Image-guided iBT yields a low rate of major complications and is effective.