[Global trends in endovascular treatment of patients with malignant neoplasms and metastatic liver damage]. / Obzor mirovykh tendentsii v interventsionnom rentgenendovaskulyarnom lechenii patsientov so zlokachestvennymi novoobrazovaniyami i metastaticheskim porazheniem pecheni.

OBJECTIVE: To analyze the results of endovascular embolization of malignant tumors and liver metastases. MATERIAL AND METHODS: We analyzed international studies on the treatment of patients with neoplastic liver lesions and complications after regional endovascular embolization following leakage of chemotherapeutic drugs from the target vessel and negative systemic effects. The results of embolization of liver arteries without chemotherapeutic drugs were also analyzed. We reviewed the PubMed, The Cochrane Library, Web of Science databases, as well as Russian scientific and practical journals. CONCLUSION: Literature data indicate high clinical effectiveness of interventional treatment of patients with malignant neoplasms and metastatic liver damage.

[Interventions for pancreatitis]. / Interventionen bei der Pankreatitis.

Approximately 20% of patients with acute pancreatitis develop complications that require surgical or radiological intervention. Radiology plays a central role, not only for imaging (course of the disease, detection of superinfection and their related complications, and development of necrosis) but also for the treatment of vascular and nonvascular complications. In the treatment of severe or necrotizing pancreatitis, a multidisciplinary staged approach with minimally invasive therapies such as endoscopic or percutaneous drainage should be used. Applying a sufficient number of drains of sufficient size, strict irrigation therapy under computed tomographic (CT) control and repositioning of the drains can successfully treat pancreatic and peripancreatic necrosis often without the need for subsequent surgical debridement. Arterial complications affect 1-10% of all patients with pancreatitis, most of which are ruptured pseudoaneurysms, which represent the most dangerous bleeding complication of pancreatitis and can be treated with a high technical success rate through embolization and/or use of an endovascular stent-graft.

Transarterial embolization (TAE) as add-on to percutaneous radiofrequency ablation (RFA) for the treatment of renal tumors: Review of the literature, overview of state-of-the-art embolization materials and further perspective of advanced image-guided tumor ablation.

Percutaneous radiofrequency ablation (RFA) for the treatment of stage I renal cell carcinoma has recently gained significant attention as the now available long-term and controlled data demonstrate that RFA can result in disease-free and cancer-specific survival comparable with partial and/or radical nephrectomy. In the non-controlled single center trials, however, the rates of treatment failure vary. Operator experience and ablation technique may explain some of the different outcomes. In the controlled trials, a major limitation is the lack of adequate randomization. In case reports, original series and overview articles, transarterial embolization (TAE) before percutaneous RFA was promising to increase tumor control and to reduce complications. The purpose of this study was to systematically review the literature on TAE as add-on to percutaneous RFA for renal tumors. Specific data regarding technique, tumor and patient characteristics as well as technical, clinical and oncologic outcomes have been analyzed. Additionally, an overview of state-of-the-art embolization materials and the radiological perspective of advanced image-guided tumor ablation (TA) will be discussed. In conclusion, TAE as add-on to percutaneous RFA is feasible and very effective and safe for the treatment of T1a tumors in difficult locations and T1b tumors. Advanced radiological techniques and technologies such as microwave ablation, innovative embolization materials and software-based solutions are now available, or will be available in the near future, to reduce the limitations of bland RFA. Clinical implementation is extremely important for performing image-guided TA as a highly standardized effective procedure even in the most challenging cases of localized renal tumors.

Cardiac volume overload and pulmonary hypertension in long-term follow-up of patients with a transjugular intrahepatic portosystemic shunt.

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPSS) cause haemodynamic changes in patients with cirrhosis, yet little is known about long-term cardiopulmonary outcomes. AIM: To evaluate the long-term cardiopulmonary outcome after TIPSS. METHODS: We evaluated cardiopulmonary parameters including echocardiography during long-term follow-up after TIPSS. Results at 1-5 years after TIPSS were compared to those of cirrhotic controls. Pulmonary hypertension (PH) diagnoses rates were included. Endothelin 1, thromboxane B2 and serotonin were measured. RESULTS: We found significant differences 1-5 years after TIPSS compared to pre-implantation values: median left atrial diameter (LAD) increased from 37 mm [interquartile range (IQR): 33-43] to 40 mm (IQR: 37-47, P = 0.001), left ventricular end-diastolic diameter (LV-EDD) increased from 45 mm (range: 41-49) to 48 mm (IQR: 45-52, P < 0.001), pulmonary artery systolic pressure (PASP) increased from 25 mmHg (IQR: 22-33) to 30 mmHg (IQR: 25-36, P = 0.038). Comparing results 1-5 years post-implantation to the comparison cohort revealed significantly higher (P < 0.05) LAD, LV-EDD and PASP values in TIPSS patients. PH prevalence was higher in the shunt group (4.43%) compared to controls (0.91%, P = 0.150). Thromboxane B2 levels correlated with PASP in the TIPSS cohort (P = 0.033). There was no transhepatic gradient observed for the vasoactive substances analysed. CONCLUSIONS: TIPSS placement is accompanied by long-term cardiovascular changes, including cardiac volume overload, and is associated with an increased rate of pulmonary hypertension. The need for regular cardiac follow-up after TIPSS requires further evaluation.

[Subintimal recanalization. Indications, technique and results]. / Subintimale Rekanalisation. Indikation, Technik und Ergebnisse.

CLINICAL/METHODICAL ISSUE: This article gives an overview of the current importance of so-called subintimal recanalization in the lower extremities. STANDARD RADIOLOGICAL METHODS: The primary technical goal of endovascular interventions in the lower extremities is the endoluminal restoration of blood circulation from the iliac arteries into the feet. METHODICAL INNOVATIONS: If endoluminal recanalization of e.g. high-grade flow-relevant stenoses or chronic total occlusion (CTO) is technically not possible, subintimal recanalization is a promising option and the only remaining minimally invasive alternative. During subintimal recanalization a channel is intentionally generated in the vessel wall (dissection) in order to bypass e. g. a chronic vascular occlusion over as short a distance as possible. PERFORMANCE: The technical success rate for subintimal recanalization of CTO of the lower extremities is 65-100 %. Technical failure occurs in approximately 25 % using the catheter and wire technique and is caused in most cases by difficulties in reaching the true lumen after the subintimal passage (the so-called re-entry). ACHIEVEMENTS: Compared to conventional subintimal recanalization, in recent years so-called re-entry devices have expanded the technical possibilities and depending on the medical experience and training level of the physician, provide an improvement in the technical success rate, a lower complication rate, a reduction of fluoroscopy time and the amount of necessary contrast medium but also result in higher costs. PRACTICAL RECOMMENDATIONS: Subintimal recanalization, whether carried out conventionally with a catheter and wire or using re-entry devices, of high-grade stenoses or CTO in the lower extremities provides a high technical success rate but requires an experienced and trained physician who is capable of operating the elaborate materials and mastering any possible complications.

Medical Liability and Patient Law in Germany: Main Features with Particular Focus on Treatments in the Field of Interventional Radiology.

UNLABELLED: On February 26th, 2013 the patient law became effective in Germany. Goal of the lawmakers was a most authoritative case law for liability of malpractice and to improve enforcement of the rights of the patients. The following article contains several examples detailing legal situation. By no means should these discourage those persons who treat patients. Rather should they be sensitized to to various aspects of this increasingly important field of law. To identify relevant sources according to judicial standard research was conducted including first- and second selection. Goal was the identification of jurisdiction, literature and other various analyses that all deal with liability of malpractice and patient law within the field of Interventional Radiology--with particular focus on transarterial chemoembolization of the liver and related procedures. In summary, 89 different sources were included and analyzed. The individual who treats a patient is liable for an error in treatment if it causes injury to life, the body or the patient's health. Independent of the error in treatment the individual providing medical care is liable for mistakes made in the context of obtaining informed consent. Prerequisite is the presence of an error made when obtaining informed consent and its causality for the patient's consent for the treatment. Without an effective consent the treatment is considered illegal whether it was free of treatment error or not. The new patient law does not cause material change of the German liablity of malpractice law. KEY POINTS: •On February 26th, 2013 the new patient law came into effect. Materially, there was no fundamental remodeling of the German liability for medical malpractice. •Regarding a physician's liability for medical malpractice two different elements of an offence come into consideration: for one the liability for malpractice and, in turn, liability for errors made during medical consultation in the process of obtaining informed consent. •Forensic practice shows that patients frequently enforce both offences concurrently.

[Drug therapy in interventional radiology]. / Medikamentöse Therapie in der interventionellen Radiologie.

In the context of pre-interventional drug therapy, a premedication is given to patients who are known to have an allergy to contrast media, have renal impairment or hyperthyroidism. An already existing anticoagulation therapy, in anticipation of the planned intervention, must be reviewed and changed or even suspended as required. For peri-interventional drug therapy it is important to consider how strenuous the procedure will be as well as the general condition of the patient. Further discussion with anesthetists may be required for the planning of pain therapy or sedation during the procedure. These factors help to ensure maximum patient comfort as well as the success of the intervention. Post-interventional anticoagulation therapy, usually started peri-interventionally, plays an important role in minimizing the risk of acute thrombosis as well as in maintaining long-term functioning of the implanted material. The form of the anticoagulation therapy is set according to the type of intervention.

[Complication management after liver transplantation. Increasing patient safety by standardized approach and interdisciplinary cooperation]. / Komplikationsmanagement nach Lebertransplantation. Erhöhung der Patientensicherheit durch standardisiertes Vorgehen und interdisziplinäre Kooperation.

The interdisciplinary management of postoperative complications in liver transplantation is of extreme importance. Due to organ shortage and prioritization of the most severely ill recipients in the model for end-stage liver disease (MELD)-based allocation, both donor and recipient associated morbidity are increasing. An interdisciplinary, structured monitoring concept is essential for the timely identification and specific treatment of postoperative complications. Interdisciplinary clinical rounds, laboratory testing and Doppler ultrasound monitoring of the graft perfusion are as important as comprehensive anti-infection prophylaxis and immunosuppression. Arterial perfusion disorders of any kind, biliary complications and postoperative fluid accumulation demand individualized therapeutic concepts. In summary, the success of liver transplantation depends on the communication and coordinated interdisciplinary cooperation of all disciplines involved.

CT-guided irreversible electroporation in an acute porcine liver model: effect of previous transarterial iodized oil tissue marking on technical parameters, 3D computed tomographic rendering of the electroporation zone, and histopathology.

PURPOSE: To evaluate the effect of previous transarterial iodized oil tissue marking (ITM) on technical parameters, three-dimensional (3D) computed tomographic (CT) rendering of the electroporation zone, and histopathology after CT-guided irreversible electroporation (IRE) in an acute porcine liver model as a potential strategy to improve IRE performance. METHODS: After Ethics Committee approval was obtained, in five landrace pigs, two IREs of the right and left liver (RL and LL) were performed under CT guidance with identical electroporation parameters. Before IRE, transarterial marking of the LL was performed with iodized oil. Nonenhanced and contrast-enhanced CT examinations followed. One hour after IRE, animals were killed and livers collected. Mean resulting voltage and amperage during IRE were assessed. For 3D CT rendering of the electroporation zone, parameters for size and shape were analyzed. Quantitative data were compared by the Mann-Whitney test. Histopathological differences were assessed. RESULTS: Mean resulting voltage and amperage were 2,545.3 ± 66.0 V and 26.1 ± 1.8 A for RL, and 2,537.3 ± 69.0 V and 27.7 ± 1.8 A for LL without significant differences. Short axis, volume, and sphericity index were 16.5 ± 4.4 mm, 8.6 ± 3.2 cm(3), and 1.7 ± 0.3 for RL, and 18.2 ± 3.4 mm, 9.8 ± 3.8 cm(3), and 1.7 ± 0.3 for LL without significant differences. For RL and LL, the electroporation zone consisted of severely widened hepatic sinusoids containing erythrocytes and showed homogeneous apoptosis. For LL, iodized oil could be detected in the center and at the rim of the electroporation zone. CONCLUSION: There is no adverse effect of previous ITM on technical parameters, 3D CT rendering of the electroporation zone, and histopathology after CT-guided IRE of the liver.

Sphere-enhanced microwave ablation (sMWA) versus bland microwave ablation (bMWA): technical parameters, specific CT 3D rendering and histopathology.

PURPOSE: This study was designed to compare technical parameters during ablation as well as CT 3D rendering and histopathology of the ablation zone between sphere-enhanced microwave ablation (sMWA) and bland microwave ablation (bMWA). METHODS: In six sheep-livers, 18 microwave ablations were performed with identical system presets (power output: 80 W, ablation time: 120 s). In three sheep, transarterial embolisation (TAE) was performed immediately before microwave ablation using spheres (diameter: 40 ± 10 µm) (sMWA). In the other three sheep, microwave ablation was performed without spheres embolisation (bMWA). Contrast-enhanced CT, sacrifice, and liver harvest followed immediately after microwave ablation. Study goals included technical parameters during ablation (resulting power output, ablation time), geometry of the ablation zone applying specific CT 3D rendering with a software prototype (short axis of the ablation zone, volume of the largest aligned ablation sphere within the ablation zone), and histopathology (hematoxylin-eosin, Masson Goldner and TUNEL). RESULTS: Resulting power output/ablation times were 78.7 ± 1.0 W/120 ± 0.0 s for bMWA and 78.4 ± 1.0 W/120 ± 0.0 s for sMWA (n.s., respectively). Short axis/volume were 23.7 ± 3.7 mm/7.0 ± 2.4 cm(3) for bMWA and 29.1 ± 3.4 mm/11.5 ± 3.9 cm(3) for sMWA (P < 0.01, respectively). Histopathology confirmed the signs of coagulation necrosis as well as early and irreversible cell death for bMWA and sMWA. For sMWA, spheres were detected within, at the rim, and outside of the ablation zone without conspicuous features. CONCLUSIONS: Specific CT 3D rendering identifies a larger ablation zone for sMWA compared with bMWA. The histopathological signs and the detectable amount of cell death are comparable for both groups. When comparing sMWA with bMWA, TAE has no effect on the technical parameters during ablation.

CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma: specific technical aspects and clinical results.

PURPOSE: This study was designed to evaluate the clinical efficacy of CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma (RCC) and to analyze specific technical aspects between both technologies. METHODS: We included 22 consecutive patients (3 women; age 74.2 ± 8.6 years) after 28 CT-guided bipolar or multipolar RF ablations of 28 RCCs (diameter 2.5 ± 0.8 cm). Procedures were performed with a commercially available RF system (Celon AG Olympus, Berlin, Germany). Technical aspects of RF ablation procedures (ablation mode [bipolar or multipolar], number of applicators and ablation cycles, overall ablation time and deployed energy, and technical success rate) were analyzed. Clinical results (local recurrence-free survival and local tumor control rate, renal function [glomerular filtration rate (GFR)]) and complication rates were evaluated. RESULTS: Bipolar RF ablation was performed in 12 procedures and multipolar RF ablation in 16 procedures (2 applicators in 14 procedures and 3 applicators in 2 procedures). One ablation cycle was performed in 15 procedures and two ablation cycles in 13 procedures. Overall ablation time and deployed energy were 35.0 ± 13.6 min and 43.7 ± 17.9 kJ. Technical success rate was 100 %. Major and minor complication rates were 4 and 14 %. At an imaging follow-up of 15.2 ± 8.8 months, local recurrence-free survival was 14.4 ± 8.8 months and local tumor control rate was 93 %. GFR did not deteriorate after RF ablation (50.8 ± 16.6 ml/min/1.73 m(2) before RF ablation vs. 47.2 ± 11.9 ml/min/1.73 m(2) after RF ablation; not significant). CONCLUSIONS: CT-guided bipolar and multipolar RF ablation of RCC has a high rate of clinical success and low complication rates. At short-term follow-up, clinical efficacy is high without deterioration of the renal function.

[Compatibility of family and profession. Survey of radiologists and medical technical personnel in clinics with different organizations]. / Vereinbarkeit von Familie und Beruf. Umfrage unter Radiologen und medizinisch-technischen Angestellten in Kliniken unterschiedlicher Ausrichtung.

PURPOSE: The compatibility of family and profession is especially difficult for employees in medical professions because of shift work and overtime. It seems that in the future women are going to represent the majority of medical professionals in Germany. Hence, with the forthcoming lack of physicians in Germany social aspects will also play a greater role in the choice of the place of employment. Therefore a statistical survey was made among employees on how they judge the compatibility of family and job and what they would like to improve. MATERIALS AND METHODS: From autumn 2009 until spring 2010 a total of 115 questionnaires were distributed to 8 different academic radiology departments. The anonymous questionnaire with partially open, partially graded questions and partially multiple answer questions was designed with the help of an expert for statistics and analytics and included questions about the employment and family situation, plans for the future, requested flexible working hours and childcare models, as well as ideas for improvement. Of the questionnaires 87 were analyzed with a specially designed access database using, for example descriptive statistics and histogram analyses. RESULTS: Of the interviewees 68% were female and 31% were male (1% not significant n.s.), 46% had children and 49% were childless (5% n.s.), 63% were medical doctors, 33% radiographers (3% other) and 82% worked full-time. Of the male respondents with children 42% indicated that their spouse was at home, 18% of female respondents with children indicated that their spouse was at home and only mothers worked part-time. Of the male respondents 73% would like to take parental leave, 44% of all respondents (70% of the male respondents and 34% of the female respondents) agreed that radiology is more compatible with family than other medical disciplines and 87% would like to have a childcare possibility in close proximity to the working place. DISCUSSION/CONCLUSIONS: In most of the families the classic role model prevails, although women are well-educated and men also set a high value on the compatibility of family and profession and would like to take parental leave and work flexible working hours. This is a chance especially for radiology.

[Transarterial ablation of hepatocellular carcinoma. Status and developments]. / Transvaskuläre Ablation des hepatozellulären Karzinoms. Ist Chemotherapie alles?

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and represents the main cause of death among European patients with liver cirrhosis. Only 30-40% of patients diagnosed with HCC are candidates for curative treatment options (e.g. surgical resection, liver transplantation or ablation). The remaining majority of patients must undergo local regional and palliative therapies. Transvascular ablation of HCC takes advantage of the fact that the hypervascularized HCC receives most of its blood supply from the hepatic artery. In this context transvascular ablation describes different therapy regimens which can be assigned to four groups: cTACE (conventional transarterial chemoembolization), bland embolization (transarterial embolization TAE), DEB-TACE (TACE with drug-eluting beads, DEB) and SIRT (selective internal radiation therapy, radioembolization). Conventional TACE is the most common type of transvascular ablation and represents a combination of intra-arterial chemotherapy and embolization with occlusion of the arterial blood supply. However, there is no standardized regimen with respect to the chemotherapeutic drug, the embolic agent, the usage of lipiodol and the interval between the TACE procedures. Even the exact course of a cTACE procedure (order of chemotherapy or embolization) is not standardized. It remains unclear whether or not intra-arterial chemotherapy is definitely required as bland embolization using very small, tightly calibrated spherical particles (without intra-arterial administration of a chemotherapeutic drug) shows tumor necrosis comparable to cTACE. For DEB-TACE microparticles loaded with a chemotherapeutic drug combine the advantages of cTACE and bland embolization. Thereby, a continuing chemotherapeutic effect within the tumor might cause a further increase in intratumoral cytotoxicity and at the same time a decrease in systemic toxicity.

Super-micro-bland particle embolization combined with RF-ablation: angiographic, macroscopic and microscopic features in porcine kidneys.

PURPOSE: To describe angiographic, macroscopic and microscopic features of super-micro-bland particle embolization in combination with RF-ablation in kidneys. Thereby, a special focus was given on the impact of the sequence of the different procedural steps. MATERIALS AND METHODS: In ten pigs, super-micro-bland particle embolization combined with RF-ablation was carried out. Super-micro-bland embolization was performed with spherical particles of very small size and tight calibration (40 ± 10 µm). In the left kidneys, RF-ablations were performed before embolization (I). In the right kidneys, RF-ablations were performed after embolization (II). The animals were killed three hours after the procedures. Angiographic (e.g. vessel architecture), macroscopic (e.g. long and short axes of the RF-ablations) and microscopic (e.g. particle distribution) study goals were defined. RESULTS: Angiography detected almost no vessels in the center of the RF-ablations in I. In II, angiography could not define the RF-ablations. Macroscopy detected significantly larger long and short axes of the RF-ablations in II compared to I (52.2 ± 3.2 mm vs. 45.3 ± 6.9 mm [P<0.05] and 25.1 ± 3.5mm vs. 20.0 ± 1.9 mm [P<0.01], respectively). Microscopy detected irregular particle distribution at the rim of the RF-ablations in I. In II, microscopy detected homogeneous particle distribution at the rim of the RF-ablations. Microscopy detected no particles in the center of the RF-ablations in I and II. CONCLUSION: The sequence of the different procedural steps of super-micro-bland particle embolization combined with RF-ablation impacts angiographic, macroscopic and microscopic features in kidneys in the acute setting.

Microwave ablation of porcine kidneys in vivo: effect of two different ablation modes ("temperature control" and "power control") on procedural outcome.

PURPOSE: This study was designed to analyze the effect of two different ablation modes ("temperature control" and "power control") of a microwave system on procedural outcome in porcine kidneys in vivo. METHODS: A commercially available microwave system (Avecure Microwave Generator; MedWaves, San Diego, CA) was used. The system offers the possibility to ablate with two different ablation modes: temperature control and power control. Thirty-two microwave ablations were performed in 16 kidneys of 8 pigs. In each animal, one kidney was ablated twice by applying temperature control (ablation duration set point at 60 s, ablation temperature set point at 96°C, automatic power set point; group I). The other kidney was ablated twice by applying power control (ablation duration set point at 60 s, ablation temperature set point at 96°C, ablation power set point at 24 W; group II). Procedural outcome was analyzed: (1) technical success (e.g., system failures, duration of the ablation cycle), and (2) ablation geometry (e.g., long axis diameter, short axis diameter, and circularity). RESULTS: System failures occurred in 0% in group I and 13% in group II. Duration of the ablation cycle was 60±0 s in group I and 102±21 s in group II. Long axis diameter was 20.3±4.6 mm in group I and 19.8±3.5 mm in group II (not significant (NS)). Short axis diameter was 10.3±2 mm in group I and 10.5±2.4 mm in group II (NS). Circularity was 0.5±0.1 in group I and 0.5±0.1 in group II (NS). CONCLUSIONS: Microwave ablations performed with temperature control showed fewer system failures and were finished faster. Both ablation modes demonstrated no significant differences with respect to ablation geometry.

Dual-energy, standard and low-kVp contrast-enhanced CT-cholangiography: a comparative analysis of image quality and radiation exposure.

OBJECTIVE: Quantitative image quality assessment in terms of image noise (IN), contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) in relation to required radiation dose (RD) for dual-energy (DE), standard and low-kVp contrast-enhanced computed-tomography (CT) cholangiography. MATERIALS AND METHODS: For each of 22 DECT-cholangiography examinations, 3 image datasets were analyzed as independent single-source CT-acquisitions at different tube potential, i.e. 80 kVp, 120 kVp-equivalent (linear blended dataset M0.3: 30% 80 kVp, 70% 140 kVp), and 140 kVp. Analysis comprised determination of IN, CNR and SNR in regions of interest (ROI) placed in liver parenchyma and contrasted bile ducts. IN was evaluated as mean standard deviation of 3 ROI placed within liver parenchyma (segments 6/7, 5/8, 2/3); CNR was assessed as bile duct-to-liver parenchyma ratio, and SNR as bile duct-to-image noise ratio. RD in terms of CT dose index (CTDI(vol)), dose-length product (DLP) and effective dose (ED) has been determined for each of the datasets, and compared to console prediction and scan summary values. Using phantom measurements of CTDI(vol), a method for separating comprehensive RD values of DE-acquisitions into the original RD contribution of each tube (80 kVp/140 kVp) has been developed, enabling comparison of all 3 datasets as if independently acquired using single-source "single-energy" technique. RESULTS: Highest IN was detected for 80 kVp- (38.6 ± 5.1HU), lowest for 120 kVp-equivalent linear blended M0.3-datasets (23.1 ± 3.4HU) with significant differences between all datasets (P<0.001). Highest SNR and CNR were measured for M0.3- (SNR: 14.8 ± 4.1; CNR: 11.6 ± 3.8) and 80 kVp-datasets (SNR: 13.8 ± 4.8; CNR: 11.2 ± 4.5); lowest for 140 kVp-datasets (SNR: 9.5 ± 2.5; CNR: 7.1 ± 2.3) with significant differences between M0.3- and 140 kVp-datasets as well as between 80 kVp- and 140 kVp-datasets (both P<0.001 for both CNR, SNR). CTDI(vol), DLP and ED were reduced by 50% for low-kilovoltage acquisitions (CTDI(vol): 5.5 ± 1.4 mGy; DLP: 127.8 ± 40.1 mGy cm; ED: 1.9 ± 0.6 mSv) compared to comprehensive DE-acquisitions (CTDI(vol): 11.0 ± 2.3 mGy; DLP: 253.8 ± 67.5 mGy cm; ED: 3.8 ± 1.0 mSv, tube contribution: 80 kVp: 44.5%; 140 kVp: 55.5%), and by 20% compared to conventional acquisitions at 120 kVp (CTDI(vol): 6.71 mGy; DLP: 153.5 ± 16.9 mGy cm; ED: 2.3 ± 0.3 mSv). CONCLUSIONS: Despite higher IN, low-kilovoltage CT-cholangiography reveals no significant difference with respect to CNR and SNR when compared to linear blended images yielded by DECT. Compared to DECT or conventional CT at 120 kVp, contrast-enhanced low-kVp CT cholangiography potentially allows reduction of patient dose by up to 50% or 20%, respectively. Therefore, CT-cholangiography at 80 kVp should be considered as an alternative to DECT-cholangiography whenever DECT is unavailable, or if increased image quality of DECT regarding quantitative bile duct evaluation is not needed for diagnosis.

Dual-energy CT-cholangiography in potential donors for living-related liver transplantation: improved biliary visualization by intravenous morphine co-medication.

PURPOSE: To prospectively evaluate whether intravenous morphine co-medication improves bile duct visualization of dual-energy CT-cholangiography. MATERIALS AND METHODS: Forty potential donors for living-related liver transplantation underwent CT-cholangiography with infusion of a hepatobiliary contrast agent over 40 min. Twenty minutes after the beginning of the contrast agent infusion, either normal saline (n=20 patients; control group [CG]) or morphine sulfate (n=20 patients; morphine group [MG]) was injected. Forty-five minutes after initiation of the contrast agent, a dual-energy CT acquisition of the liver was performed. Applying dual-energy post-processing, pure iodine images were generated. Primary study goals were determination of bile duct diameters and visualization scores (on a scale of 0 to 3: 0--not visualized; 3--excellent visualization). RESULTS: Bile duct visualization scores for second-order and third-order branch ducts were significantly higher in the MG compared to the CG (2.9±0.1 versus 2.6±0.2 [P<0.001] and 2.7±0.3 versus 2.1±0.6 [P<0.01], respectively). Bile duct diameters for the common duct and main ducts were significantly higher in the MG compared to the CG (5.9±1.3 mm versus 4.9±1.3 mm [P<0.05] and 3.7±1.3 mm versus 2.6±0.5 mm [P<0.01], respectively). CONCLUSION: Intravenous morphine co-medication significantly improved biliary visualization on dual-energy CT-cholangiography in potential donors for living-related liver transplantation.