Radiation protection in CT-guided interventions: does real-time dose visualisation lead to a reduction in radiation dose to participating radiologists? A single-centre evaluation.

AIM: To evaluate if real-time dose visualisation during computed tomography (CT)-guided interventions leads to a reduction in radiation dose to participating radiologists. MATERIALS AND METHODS: The individual radiation dose radiologists are exposed to during CT interventions was measured using dedicated dosimeters (RaySafe i2-system, Unfors RaySafe GmbH, Billdal, Sweden) worn over the usual radiation protective apron. Initially, only the total radiation dose was measured, without visualisation (control group). In the following study period, the radiation dose was shown to participants on a live screen in real-time (experimental group). In both groups, the dose was recorded in 1-second intervals. The results collected were evaluated by comparison using descriptive statistics and mixed-effect models. In particular, the variables experience, gender, role, and position during the intervention were analysed. RESULTS: In total, 517 measurements of 304 interventions (n=249 with and n=268 without live screen) performed by 29 radiologists acting as interventionalists or assistants were analysed. All CT-guided interventions were performed percutaneously, the majority of which (n=280) were microwave ablations (MWA). Radiation doses in the group without visualisation were comparable with usual dose rates for the corresponding intervention type. The mean total radiation dose was reduced by 58.1% (11.6 versus 4.86 µSv) in the experimental group (p=0.034). The highest reduction of 78.5% (15.55 versus 3.35 µSv) was observed in radiologists with the role of assistant (p=0.002). Sub-analysis showed significant dose reduction (p<0.0001) for the use of live screen in general; considering all variables, the role "assistant" alone had a statistically significant influence (p=0.002). CONCLUSION: The real-time visualisation of active radiation dose during CT interventions leads to a relevant reduction in radiation dose to participating radiologists.

Minimally invasive screw fixation of fractures in the thoracic spine: CT-controlled pre-surgical guidewire implantation in routine clinical practice.

AIM: To evaluate the feasibility and accuracy of minimally invasive, transpedicular screw placement in cervicothoracic fractures with the help of computed tomography (CT)-controlled guidewires. MATERIALS AND METHODS: Two hundred and ninety-three guidewires were inserted in 35 patients (42.9±21.2 years) under CT fluoroscopy (286 thoracic, seven cervical). There were 28 traumatic cases, three pathological fractures, three fractures due to infectious infiltrations, and one osteoporotic fracture. In 151 pedicles, screw placement was performed in the CT room. CT images were reviewed regarding accuracy and cortical violations using the popular 2 mm increment deviation classification of Gertzbein and Robbins. RESULTS: Guidewire implantation resulted in only 28 cortical contacts. Minor encroachments of the pedicle wall by inserted screws occurred in 39.1% (59 of 151) and in 23.8% if taking unavoidable encroachments into account (30 of 59). Pedicular isthmus width correlated to cortical guidewire contacts (r=-0.449; p=0.077) and pedicle violations (all graded "A") by the inserted screws (r=-0.581; p=0.049). Total procedural duration was 138.6±44.2 minutes, representing 14.5±11.6 minutes for each pedicle, while showing a significant correlation against higher vertebral levels (r=-0.849; p=0.0002) and the occurrence of pedicle violations (r=-0.641; p=0.027). CONCLUSIONS: The treatment of vertebral fractures with a guidewire-based pedicle screw insertion technique under CT imaging results in very high accuracy and a low complication rate.

Body packers on your examination table: How helpful are plain x-ray images? A definitive low-dose CT protocol as a diagnosis tool for body packers.

AIM: To analyze the clinical value and radiation dose of plain x-rays and CT in examining patients suspected of ingesting drug-filled packets. MATERIALS AND METHODS: Thirty-eight patients with suspected internal concealment of drug-filled packets who were examined with plain x-rays or CT or both were included in the study. CT studies were performed using low-dose and standard-dose techniques. All radiographic images were analysed by two radiologists regarding identification of the packets and estimating the effective radiation dose from standard- and low-dose CT versus conventional x-ray examinations. Descriptive calculations were made regarding the number and density of packs and radiation dosage. The diagnostic performance of both radiologists with standard- and low-dose CT was calculated by analysing differences in the mean number of packs found. RESULTS: Thirty-one patients were positively identified as body packers with an average of 13 packs (min: n = 1, max: n = 58, total: n = 390); seven patients were not concealing drug packets. X-ray images were taken of 24 patients prior to CT, thus allowing a direct comparison between the two methods. The correct diagnosis was made in 42%, in 33% the radiologists were uncertain, and in 25% of drug packets were either not or wrongly identified. X-ray imaging had a positive predictive value of 20% with a negative predictive value of 81%. A total of 55 CT examinations were performed on all patients with a mean effective dose of 2 mSv (low dose) versus 9.3 mSv (standard dose). The visibility of packets on low-dose CT images compared to high-dose CT was not reduced: the radiologists identified 385 and 381 of the packets, respectively, with no difference regarding the examination technique (p = 0.24 and p = 0.253, respectively). The radiodensity of all drug-filled packets at CT ranged from 26-292 HU (mean 181.2 HU). CONCLUSION: X-ray imaging of supposed body packers leads to a significant risk of diagnostic errors and additional need for CT. Instead, a single abdominal low-dose CT examination will deliver the correct diagnoses in most cases, leading to safe clinical management of the suspects.

MR-guided laser-induced thermotherapy (LITT) in patients with liver metastases of uveal melanoma.

PURPOSE: Evaluation of the local tumour control rate and survival data for magnetic resonance (MR) imaging-guided laser ablation of uveal malignant melanoma liver metastases by using laser-induced interstitial thermotherapy (LITT). MATERIALS AND METHODS: The LITT was performed in 18 patients with liver metastases (n = 44) from uveal malignant melanoma. All patients tolerated this intervention well. With the Kaplan-Meier method, the survival rates were calculated. Indications for the procedure were defined for patients with no more than five metastases, none of which were larger than 5 cm in diameter: The Indication for LITT treatment were recurrent liver metastases after partial liver resection (22%), locally non-resectable tumours (17%) or metastases in both liver lobes (61%). RESULTS: The mean survival rate for all treated patients was 3.6 years (95% CI: 2.19, 5.06). We started the calculation on the date of diagnosis of the metastases treated with LITT. The median survival was 1.83 years; 1-year survival, 88%; 3-year survival 47%, 5-year survival 17%. Calculated after the first LITT treatment the median survival was 2.8 years (95% CI: 1.0, 5.0). 10 patients were treated by transarterial chemoembolization before LITT. CONCLUSION: MR-guided LITT treatment shows a high local tumour control and survival rates in patients with liver metastases of uveal malignant melanoma.

[Surgical treatment of scapholunate ligament injuries: clinical and radiological results]. / Operative Therapie bei skapholunären Bandverletzungen: Klinische und radiologische Ergebnisse.

BACKGROUND: The purpose of this work was to retrospectively evaluate clinical and radiological results after surgical treatment for scapholunate ligament ruptures. MATERIALS AND METHODS: Measurements of range of motion, strength, and angles, as well as postoperative score assessments were performed in 32 patients. RESULTS: The average mobility in the operated wrist was 52° for flexion, extension 57°, radial 24°, ulnar deviation 31° and forearm rotation outward 88° and inward 89°. The recovery of force was 89% compared with the healthy hand. It showed an average skapholunar angle of 63°, a radioulnar angle of 22° and an average carpal height according to Nattrass of 1.49. Our patients rated the operation result with a median DASH score of 11 points (range 0-70.8 points). The median objective Mayo Wrist Score was 80 points (range 45-100 points). CONCLUSION: Surgical treatment of scapholunate ligament rupture, especially against the background of carpal collapse, is a very satisfactory method with very good results in the objective function and strength, and a high level of patient satisfaction.

Hepatic arterial infusion with irinotecan in patients with liver metastases of colorectal cancer: results of an extended phase I study.

BACKGROUND: To define the maximum tolerated dose (MTD) tolerability and efficacy of intra-arterial chemotherapy with irinotecan in patients with liver metastases of colorectal carcinoma (CRC). METHODS: Superselective intra-arterial irinotecan was applied on days 1, 14, 28 and 42. The initial dose was 140 mg/m² with escalation in the subsequent patient group to 160 mg/m². The final protocol toxicity evaluation was 260 mg/m². Patients required histologically proven disease and adequate bone marrow, liver and renal function, no extrahepatic metastasis and a life expectancy >12 weeks. results: Thirty-three patients were enrolled (median age 65, range 49-78 years). On dose level VI (240 mg/m²), 1 case of dose-limiting toxicity (DLT) (granulocytopenia) was observed, leading to an enlarged cohort of 6 patients. As no additional DLT was detected on this level, an escalation to level VII was performed. On the dose level of 260 mg/m², irinotecan DLTs were observed, resulting in the termination of escalation and the declaration of dose level VI as MTD. Imaging follow-up with Response Evaluation Criteria in Solid Tumors (RECIST) criteria revealed a complete response in 1 patient, stable disease in 31 patients, and progressed disease in 1 patient. The median time to progression was 4.7 months, the median overall survival 15.6 months. CONCLUSION: The method of intra-arterial chemotherapy with irinotecan is well tolerated and shows promising local response rates in liver metastases of CRC.

Repeated transarterial chemoembolisation using different chemotherapeutic drug combinations followed by MR-guided laser-induced thermotherapy in patients with liver metastases of colorectal carcinoma.

BACKGROUND: To evaluate a treatment protocol with repeated transarterial-chemoembolisation (TACE) downsizing before MR-guided laser-induced interstitial thermotherapy (LITT) using different chemotherapeutic combinations in patients with unresectable colorectal cancer (CRC) liver metastases. METHODS: Two hundred and twenty-four patients were included in the current study. Transarterial-chemoembolisation (mean 3.4 sessions per patient) was performed as a downsizing treatment to meet the LITT requirements (number5, diameter <5 cm). The intra-arterial protocol consisted of either Irinotecan and Mitomycin (n=77), Gemcitabine and Mitomycin (n=49) or Mitomycin alone (n=98) in addition to Lipiodol and Embocept in all patients. Post TACE, all patients underwent LITT (mean 2.2 sessions per patient). RESULTS: Overall, TACE resulted in a mean reduction in diameter of the target lesions of 21.4%. The median time to progression was 8 months, calculated from the start of therapy and the median local tumour control rate was 7.5 months, calculated as of therapy completion. Median survival of patients calculated from the beginning of TACE was 23 months (range 4-110 months), in patients treated with Irinotecan and Mitomycin the median was 22.5 months, Gemcitabine and Mitomycin 23 months and Mitomycin only 24 months with a statistically significant difference between the groups (P<0.01). CONCLUSION: Repeated TACE offers adequate downsizing of CRC liver metastases to allow further treatment with LITT. The combined treatment illustrates substantial survival rates and high local tumour control with statistically significant differences between the three protocols used. Further randomised trials addressing the current study results are required.

Role of uterine artery Doppler in the management of uterine leiomyoma by arterial embolization.

OBJECTIVES: To study Doppler changes in the uterine artery immediately following and 3 months after uterine artery embolization (UAE) and to test the feasibility of using uterine artery Doppler as a predictor of the predominant side of arterial supply to leiomyomas, amount of embolizing material needed and leiomyoma tumor volume at follow-up. METHODS: The study included 38 patients undergoing UAE for leiomyomas. Uterine artery Doppler was performed transabdominally before, within 6 hours after and 3 months after UAE to determine the peak systolic (PSV) and end-diastolic (EDV) velocities and resistance index (RI). Leiomyoma volume was measured using contrast-enhanced magnetic resonance imaging (MRI) before and 3 months after UAE. The predominant side of arterial supply to the leiomyoma was determined on digital subtraction angiography using the uterine artery diameter and tumor blush after contrast injection. For correlations with leiomyoma volume, the average PSV, EDV and RI of both sides was used, while for prediction of the predominant side of supply and for correlation with the amount of embolizing material needed, separate measurements from each side were used. RESULTS: Relative to the pre-embolization value, the uterine artery PSV and EDV were significantly reduced (P < 0.05) immediately following UAE, while the RI was significantly elevated (P < 0.05). For prediction of the predominant side of supply, the lowest RI showed the highest accuracy (81.6%). There was no significant correlation between the pre-embolization PSV, EDV or RI and the amount of embolizing material utilized. Immediately post-embolization EDV and RI values were statistically significantly correlated with the 3-month follow-up leiomyoma volume, with RI showing the strongest correlation (P = 0.0400 and 0.0002, rho = 0.34 and - 0.58, respectively). The leiomyoma volume was predicted to have reduced by 38-61% after 3 months if the immediate post-embolization average RI value was between 0.82 and 0.88. CONCLUSION: Pre-interventional Doppler assessment can be used to predict the predominant side of supply to leiomyomas but not the amount of embolizing material needed. Immediate post-interventional Doppler assessment can predict the leiomyoma volume after UAE.

Stenting of stenotic mesenteric arteries for symptomatic chronic mesenteric ischemia.

BACKGROUND: We report the results of our single center series of patients with chronic mesenteric ischemia (CMI) to determine the role of stenting in the management of patients. PATIENTS AND METHODS: We retrospectively reviewed all patients with CMI treated endovascularly with stent revascularisation from January 2008 to January 2011.CMI diagnosis was made according to clinical symptoms, including postprandial abdominal pain, food fear, and weight loss. Additionally, the diagnosis was confirmed by duplex ultrasonography and/or computed tomography angiography and/or contrast-enhanced magnetic resonance angiography. RESULTS: All 45 patients presented with typical CMI symptoms: 45/45 (100 %) had postprandial pain, 31/45 (68.8 %) had a weight loss of more than 10 kilograms, and 11/45 (24.4 %) suffered from ischemic colitis combined with lower gastrointestinal bleeding. In three patients occlusion could not be crossed, therefore considered as technical failure. A total of 55 arteries were stented in the remaining 42 patients. Nineteen patients underwent SMA stenting alone, eight underwent celiac stenting, alone and three patients underwent stenting of inferior mesenteric artery (IMA) alone. We performed combined stenting of the celiac artery and superior mesenteric artery in ten patients, and one patient underwent a combined stenting of the celiac artery and the IMA. All three mesenteric arteries were stented in only one patient. Primary technical success was achieved in 42/45 (94.8 %) patients. Clinical symptom relief was achieved in 39/45 (86.6 %) patients with abdominal pain. Increased body weight was observed in 28/31 (90.3 %) patients with an average weight gain of 8.8 kilograms (5 - 12 kilograms), and 10/11 (90.9 %) patients recovered from ischaemic colitis/lower gastrointestinal bleeding. CONCLUSIONS: Stent revascularisation can be considered as the first-line therapy for patients with chronic mesenteric ischemia.

Direct implantation of VX-2 carcinoma: a new rabbit bone model using a three-dimensional matrix as a carrier for the tumor cells.

BACKGROUND: Animal bone models are inevitable for musculoskeletal research. The induction of a local bone tumor is complex and time consuming. In this study a new model is presented using a direct implantation of tumor cells into the bone without a preliminary passaging of the cells. METHODS: A three-dimensional matrix consisting of alginate spheroids and carrying the VX-2 tumor suspension was used for implantation into the bone of 6 female New Zealand white rabbits. X-ray imaging, CT and MRI scans as well as a histological examination were carried out. RESULTS: All rabbits developed local bone tumor in the metaphysis of the femoral leg. Bone tumor was identifiable on average 6.2 weeks after implantation. Fluoroscopy, CT and MRI scans showed a cortical reaction but no destruction of the compact bone together with a mean tumor size of 14 mm. Histological examination revealed a tumor infiltration with an activation of osteoclasts and an osteoclastic resorption. CONCLUSION: The direct implantation of a VX-2 tumor suspension into the rabbit bone using alginate spheroids is an effective and reproducible way to successfully induce bone tumor. This new animal model allows further examination of surgical and minimal invasive therapy in musculoskeletal research.

Duration of dysmenorrhoea and extent of adenomyosis visualised by magnetic resonance imaging.

OBJECTIVE: Enlargement of the junctional zone (JZ) on T2-weighted resonance imaging of the uterus has recently been established as the major criterion for adenomyosis in patients with endometriosis. This study was conducted to analyse the extent of adenomyosis using magnetic resonance imaging (MRI) and relate it to the duration of dysmenorrhoea. STUDY DESIGN: This was a prospective study of 70 patients presenting with the complaint of severe dysmenorrhoea. Forty patients (57%) reported dysmenorrhoea as their major complaint and 30 patients (43%) suffered additionally from infertility. Group I (n=40) consisted of patients with dysmenorrhoea of between 1 and 10 years' duration, group II (n=30) consisted of patients with dysmenorrhoea of longer than 11 years' duration. All patients underwent laparoscopy to detect the presence and degree of endometriosis, and all patients underwent T2-weighted resonance imaging of the uterus to detect the extent of adenomyosis by measurement of the "junctional zone". RESULTS: In group I, adenomyosis could be detected via MRI in 21 patients (52.5%), while 19 patients (47.5%) showed no signs of adenomyosis. By contrast, in group II a distinct enlargement of the JZ, as the major radiological criterion of adenomyosis, could be observed in 26 patients (87%), while only 4 patients (13%) revealed no signs of adenomyosis (p=0.04). The mean thickness of the JZ was significantly enlarged in group II (11.07 mm) compared with group I (6.38 mm; p<0.0001). The prevalence of adenomyosis in endometriosis after dysmenorrhoea of more than 11 years' duration was 87%. CONCLUSIONS: In deep infiltrating endometriosis, a correlation between a specific localisation and dysmenorrhoea can often not be found. Recently, endometriosis and adenomyosis have been believed to result from a common uterine disease, the dislocation of the basal endometrium. Our data clearly show that dysmenorrhoea of long duration in patients who have had endometriosis for over a threshold value of 11 years is significantly related to adenomyosis of the uterus. Hence, evaluation of adenomyosis using MRI should become a standard procedure in cases of dysmenorrhoea and endometriosis. Severe dysmenorrhoea of long duration should always focus clinical interest on adenomyosis of the uterus.

[Palliative treatment of primary lung tumors with transpulmonary chemoembolization (TPCE)]. / Transpulmonale Chemoembolisation (TPCE) als palliatives Behandlungskonzept bei primären Lungentumoren.

PURPOSE: To evaluate transpulmonary chemoembolization (TPCE) as a symptomatic palliative method for treating inoperable primary lung tumors. MATERIALS AND METHOD: From 2002 to 2005, 17 patients (17 males, 3 females; average age: 64.5 years) suffering from primary lung tumors were treated in 3.6 sessions (range: 2 to 8) using TPCE. The patients had the following primary tumors: adenocarcinoma (n = 6), pleural mesothelioma (n = 2), squamous cell carcinoma (n = 1), small cell carcinoma (n = 1), and non-small cell carcinoma (n = 7). After femoral vein puncture, tumor-supplying pulmonary arteries were selectively explored, and 5 - 10 mg mitomycin C and 5 - 10 mL lipiodol and microsphere particles (Spherex) (20 - 70 microm in diameter) were applied with balloon protection. Diagnosis and follow-up were performed in 4-week intervals with unenhanced and contrast-enhanced computed tomography (CT). The mean follow-up was 11.3 months. RESULTS: Treatment was well tolerated by all patients with no major side effects or complications. The laboratory parameters were not significantly influenced. 11.8 % of the patients (n = 2) showed high or moderate lipiodol uptake, and 76.5 % (n = 13) showed low lipiodol uptake. After evaluation of morphologic criteria, a mean volume regression of 12.1 ml (40.4 %) of the embolized areas was achieved in four patients (23.5 %), while a constant value was identified during follow-up for seven patients (41.2 %). In six patients (35.3 %), progression of the treated lung tumors was recorded. The tumor increased by a mean of 38.37 ml (165.38 %). CONCLUSION: TPCE is a well-tolerated palliative treatment option for patients with primary lung tumors.

[Transarterial chemoperfusion of the pelvis--results in symptomatic locally recurrent tumors and lymph node metastases]. / Transarterielle Chemoperfusion des Beckens--Ergebnisse bei symptomatischen Rezidivtumoren und Lymphknotenmetastasen.

PURPOSE: To evaluate local transarterial chemoperfusion (TACP) of therapy-resistant, locally recurrent malignant tumors and lymph node metastases in the pelvis with respect to clinical response, tumor response and survival. MATERIALS AND METHODS: Between 2003 and 2005, 24 outpatients (median age 56.5 years, range 33-82) were treated with 128 TACPs (min. 3; mean 5 sess/patient) in 4-week intervals. Depending on the tumor location and vascularization, a fluoroscopy catheter was placed either in the abdominal aorta or internal pelvic artery. A combination of mitomycin C (6 mg/m (2)) and gemcitabine (1500 mg/m (2)) was administered over 60 minutes. The tumor size was measured using CT or MRI. The radiological response was classified according to RECIST (Response Evaluation Criteria In Solid Tumors) as "complete response" (CR), "partial response" (PR), "stable disease" (SD) and "progressive disease" (PD). The clinical response was classified as "response (clinical)" if the symptoms improved distinctly, "stable disease (clinical)" if complaints were stabilized, and "progression (clinical)" if symptoms deteriorated or new symptoms appeared. After the third TACP, patients were evaluated for clinical and radiological response. In the case of clinical and radiological progression, therapy was stopped and the patient was referred to the hospital's tumor board. In the case of radiological response and clinical progression or clinical response and radiological progression, therapy was continued. Therapy could be stopped by the patient at any time. RESULTS: Treatment was tolerated well by all patients. No clinically relevant problems and no grade III or IV toxicity according to CTC (Common Toxicity Criteria) appeared. Tumor-related pain, bleeding, restricted mobility of the lower extremities, incontinence, urinary tract obstruction, and constipation were reduced in 9/17, 5/6, 3/3, 1/3, 2/5, and 1/3 of cases (clinical response rate: 54%). Radiologically, 4/24 (17%) patients showed PR, 12/24 (50%) SD, and 8/24 (34%) PD (tumor control (PR+SD): 67% of cases). Tumor response (median survival since first TACP) was as follows: colorectal: 2 PR, 7 SD, 2 PD (11.5 months), ovarian: 1 SD, 2 PD (8.5 mon), cervical: 1 PR, 1 SD (6 mon), breast: 2 SD (6 mon), gastric: 1 PD (11 mon), adrenal gland: 1 PD (12 mon), anal: 1 PD (10 mon), prostate: 1 PD (20 mon), Gartner's duct: 1 PR (20 mon), renal cell carcinoma: 1 SD (10 mon). CONCLUSION: Since tumor-related complaints were improved in 54% of the cases and control of tumor growth (PR+SD) was achieved in 67% of the cases, TACP for recurrent pelvic malignancies should be considered as a palliative oncological treatment option.

[Transarterial chemoperfusion with gemcitabine and mitomycin C in pancreatic carcinoma: results in locally recurrent tumors and advanced tumor stages]. / Transarterielle Chemoperfusion mit Gemcitabine und Mitomycin C bei Pankreaskarzinom: Ergebnisse bei Rezidivtumoren und fortgeschrittenen Tumorstadien.

PURPOSE: The purpose of this study was to evaluate local transarterial chemoperfusion (TACP) in locally recurrent pancreatic carcinoma and advanced tumor stages which did not respond to prior systemic chemotherapy. The tumor response, survival, and pain response were retrospectively analyzed. MATERIALS AND METHOD: Forty outpatients (median age 62 years, range 36-79) were treated with a minimum of 3 (mean 6, range 3-12) applications per patient in four-week intervals. Twenty-eight patients were in advanced tumor stages, and 12 patients had locally recurrent tumors. Gemcitabine (1,000 mg/m(2)) and mitomycin C (8.5 mg/m(2)) were administered within 1 hour through a celiac trunk catheter. The tumor response (diameter, volume) was measured using MRI or CT and classified according to RECIST. The pain response was defined as a reduction of pain intensity of more than 50% on a visual analog scale, or a reduction of more than 50% in analgesics consumption, or a switch to a less potent analgesic agent. RESULTS: The treatment was tolerated well by all patients. No clinically relevant problems or grade III or IV toxicity according to CTC (Common Toxicity Criteria) were observed. Tumor-related pain was relieved in 20/32 (62.5%) cases. Radiologically, "complete response" was found in 3/40 (7.5%), "partial response" in 9/40 (22.5%), "stable disease" in 16/40 (40%), and "progressive disease" in 12/40 (30%) of the patients. The median survival period since initial diagnosis and first TACP was 16.4 months and 8.1 months, respectively. Locally recurrent tumors showed better, but still not significant results regarding tumor response (41.7% vs. 25%) as well as survival (14.4 vs. 7 months) compared to advanced tumor stages. Responders (CR+PR) showed a significant survival advantage compared to patients with tumor progression (13.0 vs. 6.0 months; p=0.013). CONCLUSION: TACP is a minimally invasive outpatient treatment for therapy-resistant locally recurrent pancreatic carcinoma and advanced tumor stages. It may be considered as an important aspect in palliative symptomatic pain-relieving treatment, or may even result in improved survival by achieving tumor response.

[Transarterial chemoembolization (TACE) in hepatocellular carcinoma: technique, indication and results]. / Transarterielle Chemoembolisation (TACE) des hepatozellulären Karzinoms: Technik, Indikationsstellung und Ergebnisse.

UNLABELLED: To present current data on technique, indications and results of transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). The principle of TACE is the intra-arterial injection of chemotherapeutic drug combinations like doxorubicin, cisplatin and mitomycin into the hepatic artery, followed by lipiodol injection, Gelfoam for vessel occlusion and degradable microspheres. The side effects and complications after TACE range from fever, upper abdominal pain and vomiting to acute or chronic liver cell failure. The palliative effect in unresectable HCC using TACE allows local tumor control in 15 to 60% of cases and 5-year survival rates ranging from 8-43%. The potentially curative treatment option allows local tumor control from 18-63%. The neoadjuvant treatment option of TACE in combination with other treatment options like percutaneous ethanol injection (PEI) or radiofrequency ablation (RFA) reach local tumor control rates between 80-96%. The bridging effect of TACE before liver transplantation reaches 5-year survival rates from 59-93%. The symptomatic therapy option of TACE is used to counteract pain directly caused by HCC and acute/subacute bleeding in the HCC. The local tumor response reaches up to 88% and the bleeding control is from 83 to 100%. CONCLUSION: TACE is a potentially curative, palliative, neoadjuvant, bridging and symptomatic therapy option for local and diffuse HCC.

Continuous-flow DNP polarizer for MRI applications at 1.5 T.

Here we describe a new hyperpolarization approach for magnetic resonance imaging applications at 1.5 T. Proton signal enhancements of more than 20 were achieved with a newly designed multimode microwave resonator situated inside the bore of the imager and used for Overhauser dynamic nuclear polarization of the water proton signal. Different from other approaches in our setup the hyperpolarization is achieved continuously by liquid water flowing through the polarizer under continuous microwave excitation. With an available flow rate of up to 1.5 ml/min, which should be high enough for DNP MR angiography applications in small animals like mice and rats. The hyperpolarized liquid cooled to physiological temperature can be routed by a mechanical switch to a quartz capillary for injection into the blood vessels of the target object. This new approach allows hyperpolarization of protons without the need of an additional magnet and avoids the losses arising from the transfer of the hyperpolarized solution between magnets. The signal-to-noise improvement of this method is demonstrated on two- and three-dimensional phantoms of blood vessels.

Intra-individual comparison of CAIPIRINHA VIBE technique with conventional VIBE sequences in contrast-enhanced MRI of focal liver lesions.

PURPOSE: To evaluate the impact of controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) volume interpolated breath-hold examination (VIBE) magnetic resonance imaging (MRI) technique on image quality, reader confidence, and inter-observer agreement for the assessment of focal liver lesions in comparison with the standard VIBE approach. MATERIAL AND METHODS: In this IRB-approved intra-individual comparison study, abdominal arterial and portal-venous contrast-enhanced MRI studies were retrospectively analyzed in 38 patients with malignant liver lesions. Each patient underwent both CAIPIRINHA and conventional VIBE 3T MRI within 3 months, showing stable disease. Images were evaluated using 5-point rating scales by two blinded radiologists with more than 20 and 5 years of experience in MRI, respectively. Readers scored dignity of liver lesions and assessed which liver segments were affected by malignancy (ranging from 1=definitely benign/not affected to 5=definitely malignant/affected by malignancy). Readers also rated overall image quality, sharpness of intrahepatic veins, and diagnostic confidence (ranging from 1=poor to 5=excellent). RESULTS: Reviewers achieved a higher inter-observer reliability using CAIPIRINHA when they reported which liver segments were affected by malignancy compared to traditional VIBE series (κ=0.62 and 0.54, respectively, p<0.05). Similarly, CAIPIRINHA showed a slightly higher inter-rater agreement for the dignity of focal liver lesions versus the standard VIBE images (κ=0.50 and 0.49, respectively, p<0.05). CAIPIRINHA series also scored higher in comparison to standard VIBE sequences (mean scores: image quality, 4.2 and 3.5; sharpness of intrahepatic vessels, 3.8 and 3.2, respectively, p<0.05) for both reviewers and allowed for higher subjective diagnostic confidence (ratings, 3.8 and 3.2, respectively, p<0.05). CONCLUSION: Compared to the standard VIBE approach, CAIPIRINHA VIBE technique provides improved image quality and sharpness of intrahepatic veins, as well as higher diagnostic confidence. Additionally, this technique allows for higher inter-observer agreement when reporting focal liver lesions for both dignity and allocation.

Magnetic resonance imaging evaluation of lipodystrophy in HIV-positive patients receiving highly active antiretroviral therapy.

We evaluated retrospectively an automated method for the separate detection of subcutaneous and visceral fat in the abdominal region by magnetic resonance studies in HIV-positive patients on highly active antiretroviral therapy. The patients were divided into four different groups: lipoatrophy, lipohypertrophy, mixed and the control group. The use of software for the automated detection of abdominal compartment visceral adipose tissue (VAT), total adipose tissue (TAT) and subcutaneous adipose tissue (SAT) was compared to manual evaluation methods (fuzzy C-mean). The results of ROC analysis showed that the parameters, particularly the VAT, are better than the VAT/TAT and at identifying patients with the symptoms of abdominal fat accumulation. A sensitivity of 80.3% and a specificity of 79.5% resulted from a threshold VAT value of >87 cm(2). Moreover, the manual evaluation method was shown to provide greater values for VAT and the VAT/TAT ratio than those given by the automated method. In the present study, a rapid MRI protocol for the detection and assessment of the course of lipodystrophy was presented and tested on a group of patients with signs of HALS, as well as on an antiretroviral naïve control group.

Radiation dose and quickness of needle CT-interventions using a laser navigation system (LNS) compared with conventional method.

PURPOSE: The aim of this study was to analyse the radiation dose and quickness of needle interventions using a Laser Navigation System (LNS-group) compared with conventional method (control-group). MATERIALS AND METHODS: In this prospective, randomized, comparative study 58 patients (19 females, 39 males; mean age, 62.9 years) were punctured either with LNS (n=29) or with conventional method with a skin mark of the puncture site (n=29). In the LNS method the puncture site was marked with laser without additional CT. Thoracic and abdominal intervention was performed in 30 and 28 patients, respectively. Radiation dose and time of the procedures were analysed. Statistical significance was calculated according to the Mann-Whitney-U-test. RESULTS: Mean target access path in the patients of the LNS group was 6.0 cm (range, 3.0-10.1cm) and in the control group 6.0 cm (range, 1.0-10.3 cm). Time duration of complete intervention in the LNS group was 20:25 min (range, 07:00-34:00 min) and in the control group 28:00 min (range, 13:00-51:00 min). The dose-length-product (DLP) of intervention scan of the LNS group was 42.3 mGy cm (range, 10-125 mGy cm), and of the control group 59.7 mGy cm (range, 25-176.42 mGy cm). CONCLUSION: Using the LNS for CT-guided interventions results in faster intervention time with a lower dose.

[Embolization of symptomatic myomas (UAE): technique, indication and results]. / Embolisation bei symptomatischen Uterus-Myomen (UAE): Technik, Indikationsstellung und Ergebnisse.

Presentation of indication, technique and results of transarterial uterine artery embolization (UAE) for the treatment of symptomatic myomas. Technical requirements are presented like DSA, catheters, superselective catheterisation and the different embolization materials as polyvinylalcohol (PVA) or microspheres, as well as the follow-up after UAE. The technical success rate of UAE is documented to range between 98 to 100 % and myomatous symptomatology disappears in 85 to 94 % of the cases. A reduction in the size of the myomata after UAE is observed between 48 to 70 %. A resolution of the hemorrhage disappears in 80 to 96 % of the cases immediately. Particulate embolization of the uterine artery is a new minimally invasive therapy in the management of symptomatic leiomyomas with a high efficiency and low rate of major complications. Further studies may prove the longterm results after UAE, the influence on fertility and possible late complications.