[Results of multimodal treatment of hepatic echinococcosis]. / Ergebnisse der multimodalen Therapie der hepatischen Echinokokkose.

BACKGROUND: Echinococcosis is a rare parasitosis in Germany for which the World Health Organization recommends stage-specific treatment strategies. OBJECTIVE: The aim of this study was to analyze the treatment results of patients with hepatic echinococcosis at a German center of excellence for liver surgery. METHODS: Patients who underwent surgery for hepatic echinococcosis between 2009 and 2018 at the University Hospital of Mainz (UMM) were included in this follow-up examination. The investigation included a magnetic resonance imaging (MRI) of the abdomen, documentation of the quality of life (QoL), serological and laboratory parameters. In addition, an online survey was performed among surgeons from Middle Rhein and gastroenterologists from Rhineland-Palatinate. RESULTS: At the UMM 25 surgical interventions were performed for hepatic echinococcosis: 9 for cystic (CE) and 16 for alveolar echinococcosis (AE). The majority of the interventions were major liver resections with additional vascular and biliary procedures. The 90-day mortality was 0%, and 4 grade 3a and 1 grade 4b complications occurred. In contrast to AE 75% of the postoperative serological results of patients with CE remained positive for more than 1 year postoperatively. Most participants in the survey knew the imaging characteristics and treatment options of AE and CE; however, many participants were unaware of the cost of the treatment. CONCLUSION: From the perspective of surgeons, hepatic echinococcosis is a challenge, which however can be curatively treated with a low morbidity despite advanced disease in many patients. Due to the low incidence of the disease, the state of knowledge about AE and CE is limited among physicians.

Hypoxia-Associated Marker CA IX Does Not Predict the Response of Locally Advanced Rectal Cancers to Neoadjuvant Chemoradiotherapy.

Hypoxia-associated proteome changes have been shown to be associated with resistance to chemo- and radiotherapy. Our study evaluated the role of the hypoxia-inducible (HIF)-1 target gene carbonic anhydrase (CA) IX in the prediction of the response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer (stages II and III). A total of 29 pretreatment biopsy specimens were stained for CA IX by immunohistochemistry, converted to digital images and evaluated in a quantitative fashion using image analysis software. Contrary to our expectations, a trend towards a correlation between better tumor regression (>50%) and higher expression of CA IX (p=0.056) was found. CA IX was also present more frequently in pathological tumor stage T1 (pT1) tumors (p=0.048). Conversely, no association with lymph node metastasis was identified. In conclusion, as a single marker, CA IX expression is not able to identify a hypoxia-related treatment resistant phenotype in rectal cancer.

Serial assessments of microvascular obstruction by contrast-enhanced magnetic resonance predict contractile recovery and clinical outcome after reperfused acute myocardial infarction.

AIMS: The purpose of the study was to investigate, using cardiac magnetic resonance (CMR), the presence and time course of microvascular obstruction (MO) in patients with acute myocardial infarction (AMI), and to test its relationship with cardiac remodeling and clinical outcomes. METHODS AND RESULTS: 53 patients with AMI and successful percutaneous reperfusion underwent CMR examination at four separate timepoints: within the first 48 hours, at 10 days, at six and twelve months after infarction. MO was quantified immediately (early imaging) and 10 minutes (late imaging) after contrast administration in each session. The extent of MO decreased from early to late imaging at both the first and the second CMR exam (p≤0.001). Early MO was absent in 18(36%) patients both at 48 hours and 10 days after AMI. At 1 year follow-up, LVEF in these patients improved to normal (median = 62% (53-70)). Early MO was present in the first but not in the second CMR in 13 (26%) patients; LVEF at one year in these patients reached a median = 52% (47-61). Finally, Early MO was present in both exams in 19 (38%) patients, who at 1 year after infarction had a LVEF of median = 49% (42-54, P≤0.001 across groups). The time course of MO was a predictor of prognosis upon Kaplan-Meier analysis (P = 0.035). The presence of MO at 10 days after AMI was associated with a higher risk of MACE during a 5-years follow-up. CONCLUSIONS: The presence of MO within 48 hours after AMI, and its time course in the following ten days, provides complementary information on both functional myocardial recovery and long-term outcome.

Visceral artery aneurysms: Incidence, management, and outcome analysis in a tertiary care center over one decade.

OBJECTIVES: To evaluate the incidence, management, and outcome of visceral artery aneurysms (VAA) over one decade. METHODS: 233 patients with 253 VAA were analyzed according to location, diameter, aneurysm type, aetiology, rupture, management, and outcome. RESULTS: VAA were localized at the splenic artery, coeliac trunk, renal artery, hepatic artery, superior mesenteric artery, and other locations. The aetiology was degenerative, iatrogenic after medical procedures, connective tissue disease, and others. The rate of rupture was much higher in pseudoaneurysms than true aneurysms (76.3% vs.3.1%). Fifty-nine VAA were treated by intervention (n = 45) or surgery (n = 14). Interventions included embolization with coils or glue, covered stents, or combinations of these. Thirty-five cases with ruptured VAA were treated on an emergency basis. There was no difference in size between ruptured and non-ruptured VAA. After interventional treatment, the 30-day mortality was 6.7% in ruptured VAA compared to no mortality in non-ruptured cases. Follow-up included CT and/or MRI after a mean period of 18.0 ± 26.8 months. The current status of the patient was obtained by a structured telephone survey. CONCLUSIONS: Pseudoaneurysms of visceral arteries have a high risk for rupture. Aneurysm size seems to be no reliable predictor for rupture. Interventional treatment is safe and effective for management of VAA. KEY POINTS: • Diagnosis of visceral artery aneurysms is increasing due to CT and MRI. • Diameter of visceral arterial aneurysms is no reliable predictor for rupture. • False aneurysms/pseudoaneurysms and symptomatic cases need emergency treatment. • Interventional treatment is safe and effective.

Dynamic contrast enhanced-MRI in rectal cancer: Inter- and intraobserver reproducibility and the effect of slice selection on pharmacokinetic analysis.

PURPOSE: To assess inter- and intraobserver reproducibility of DCE-MRI measurements and possible differences between two directly adjacent slices. MATERIALS AND METHODS: DCE-MRI measurements of 30 patients with histologically proven rectal carcinoma were performed on a 1.5 Tesla (T) MR system during intravenous contrast agent application before and after neoadjuvant radiochemotherapy with two directly adjacent slices used for calculation per patient. Images were analyzed semiquantitatively (parameters TTP and MITR) and quantitatively using the Brix compartment model (parameters kep and A) by two different observers and at two different time points. The concordance correlation coefficient was calculated for every parameter in intra-/interobserver comparison and slice comparison. RESULTS: Median relative differences below 10% for all parameters and high values of the concordance correlation coefficient (CCC) were found for most pharmacokinetic parameters in inter-/intraobserver comparison and slice comparison, with the exception of the parameter A before therapy in intra-/ interobserver comparison (CCC: 0.315/0.452) and kep before therapy in intraobserver comparison (CCC: 0.362). CONCLUSION: Our results indicate good inter- and intraobserver reproducibility for most pharmacokinetic parameters and for the two adjacent slices measured. However, as there were some parameters that demonstrated poor correlation, testing for reproducibility and a multiobserver approach might be considered whenever using pharmacokinetic parameters as biomarkers.

Rectal cancer: dynamic contrast-enhanced MRI correlates with lymph node status and epidermal growth factor receptor expression.

PURPOSE: To evaluate correlations between dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and clinicopathologic data as well as immunostaining of the markers of angiogenesis epidermal growth factor receptor (EGFR) and CXC-motif chemokine receptor 4 (CXCR4) in patients with rectal cancer. MATERIALS AND METHODS: Presurgical DCE-MRI was performed in 41 patients according to a standardized protocol. Two quantitative parameters (k21 , A) were derived from a pharmacokinetic two-compartment model, and one semiquantitative parameter (TTP) was assessed. Standardized surgery and histopathologic examinations were performed in all patients. Immunostaining for EGFR and CXCR4 was performed and evaluated with a standardized scoring system. RESULTS: DCE-MRI parameter A correlated significantly with the N category (P = 0.048) and k21 with the occurrence of synchronous and metachronous distant metastases (P = 0.029). A trend was shown toward a correlation between k21 and EGFR expression (P = 0.107). A significant correlation was found between DCE-MRI parameter TTP and the expression of EGFR (P = 0.044). DCE-MRI data did not correlate with CXCR4 expression. CONCLUSION: DCE-MRI is a noninvasive method which can characterize microcirculation in rectal cancer and correlates with EGFR expression. Given the relationship between the dynamic parameters and the clinicopathologic data, DCE-MRI data may constitute a prognostic indicator for lymph node and distant metastases in patients with rectal cancer.

Pretherapeutic MRI for decision-making regarding selective neoadjuvant radiochemotherapy for rectal carcinoma: interim analysis of a multicentric prospective observational study.

PURPOSE: To study the accuracy of different cutoffs for an involved circumferential resection margin (CRM) compared with T and N categories measured by MRI as basis for selective application of neoadjuvant radiochemotherapy (nRCT) in rectal carcinoma. MATERIALS AND METHODS: In a prospective multicenter observational study involving 153 primarily operated patients, the preoperative results of MRI with pathohistological findings of resected specimens were compared. RESULTS: For a cutoff of ≤1 mm for involvement of the CRM, the accuracy of preoperative MRI was 90.9% (139/153). The negative predictive value was 98.5% (134/136). The four participating departments did not differ significantly. For a cutoff of >2 mm and >5 mm, the rates of false-positive findings increased significantly from 5% to 12% and 35% with a decrease in accuracy to 82% and 62%, respectively. In contrast, the accuracy in predicting T (69.3%) and N categories (61.4%) was much lower. CONCLUSION: The indication for nRCT should be based on the determination of the minimal distance of the tumor from mesorectal fascia with a cutoff point of >1 mm as measured by MRI.

Rectal cancer: assessment of response to neoadjuvant chemoradiation by dynamic contrast-enhanced MRI.

PURPOSE: To assess pretreatment functional and morphological tumor characteristics with magnetic resonance imaging (MRI) in advanced rectal carcinoma and to identify factors predicting response to neoadjuvant chemoradiation. MATERIALS AND METHODS: In a prospective study, 95 patients with rectal carcinoma underwent dynamic contrast-enhanced MRI before and after chemoradiation. Quantitative parameters were derived from a pharmacokinetic two-compartment model. Tumors were also characterized with regard to mucinous status at pretreatment high-resolution MRI as nonmucinous or mucinous. Response to treatment was defined as a downshift in the local tumor stage. RESULTS: The parameter k21 (contrast medium exchange rate) was higher at pretreatment MRI in nonmucinous compared with mucinous carcinomas (P < 0.001). The effect of chemoradiation on dynamic MR parameters was higher in nonmucinous carcinomas than in the mucinous subtype (P < 0.001). A higher rate of response to treatment was linked with nonmucinous morphology (P < 0.001). Multivariate analysis revealed an association between mucinous tumor morphology and poor response (odds ratio [95% confidence interval]: 0.113 [0.032-0.395], P < 0.001) as well as an association between a high 75th percentile of k21 and a higher response rate (odds ratio: 1.043 [1.001-1.086], P = 0.019). CONCLUSION: Functional and morphological parameters of pretreatment MRI can assess tumor characteristics associated with the effectiveness of chemoradiation before treatment initiation.

Rectal Cancer: MR imaging of the mesorectal fascia and effect of chemoradiation on assessment of tumor involvement.

PURPOSE: To evaluate the impact of chemoradiation on the reliability of MRI in assessing tumor involvement of the mesorectal fascia in patients with rectal cancer. MATERIALS AND METHODS: Presurgical MRI was performed in 150 patients; among them 85 had received neoadjuvant long-course chemoradiation. A standardized imaging protocol (1.5 Tesla [T] system, image voxel size 0.6 × 0.4 × 3 mm(3) ), standardized surgery, and histopathological examination were applied for the entire patient population. Images were analyzed to identify potential tumor involvement of the mesorectal fascia (minimum tumor distance to fascia ≤1 mm) and compared with histopathology as the reference standard. Results of nonirradiated and irradiated patients were compared to define the impact of chemoradiation on imaging reliability. RESULTS: In nonirradiated patients, MRI was reliable in predicting or excluding tumor involvement of the mesorectal fascia, positive predictive value 80%, negative predictive value 89%. The frequency of overestimating tumor involvement was significantly higher in irradiated patients (P = 0.005, positive predictive value 42%). CONCLUSION: Discussions about MRI assessment of tumor involvement of the mesorectal fascia as a basis for recommending neoadjuvant chemoradiation should focus on investigations that excluded irradiated patients, because MRI is less reliable after chemoradiation and tends to overestimate mesorectal tumor involvement.

Rectal cancer: mucinous carcinoma on magnetic resonance imaging indicates poor response to neoadjuvant chemoradiation.

PURPOSE: To assess response of locally advanced rectal carcinoma to chemoradiation with regard to mucinous status and local tumor invasion found at pretherapeutic magnetic resonance imaging (MRI). METHODS AND MATERIALS: A total of 88 patients were included in this prospective study of patients with advanced mrT3 and mrT4 carcinomas. Carcinomas were categorized by MRI as mucinous (mucin proportion >50% within the tumor volume), and as nonmucinous. Patients received neoadjuvant chemoradiation consisting of 50.4 Gy (1.8 Gy/fraction) and 5-fluorouracil on Days 1 to 5 and Days 29 to 33. Therapy response was assessed by comparing pretherapeutic MRI with histopathology of surgical specimens (minimum distance between outer tumor edge and circumferential resection margin = CRM, T, and N category). RESULTS: A mucinous carcinoma was found in 21 of 88 patients. Pretherapeutic mrCRM was 0 mm (median) in the mucinous and nonmucinous group. Of the 88 patients, 83 underwent surgery with tumor resection. The ypCRM (mm) at histopathology was significantly lower in mucinous carcinomas than in nonmucinous carcinomas (p ≤ 0.001). Positive resection margins (ypCRM ≤ 1 mm) were found more frequently in mucinous carcinomas than in nonmucinous ones (p ≤ 0.001). Treatment had less effect on local tumor stage in mucinous carcinomas than in nonmucinous carcinomas (for T downsizing, p = 0.012; for N downstaging, p = 0.007). Disease progression was observed only in patients with mucinous carcinomas (n = 5). CONCLUSION: Mucinous status at pretherapeutic MRI was associated with a noticeably worse response to chemoradiation and should be assessed by MRI in addition to local tumor staging to estimate response to treatment before it is initiated.

Permanent stoma after low anterior resection for rectal cancer.

BACKGROUND AND OBJECTIVES: A low anterior resection procedure for removing a rectal tumor aims to preserve the sphincter and avoid a permanent stoma. Permanent stomas are primarily necessary in cases of poor anorectal function and local recurrence. The aim of this study was to clarify whether anastomosis-related complications and local recurrence influenced the rate of permanent stomas in a long-term follow-up. METHODS: Of 1032 consecutive patients with rectal cancer, 397 were treated by low anterior resection (R0 and R1 resections) between 1985 and 2007 at the Department of General and Abdominal Surgery of the University Hospital, Mainz (Germany). All patient data were collected prospectively. A retrospective, multivariate analysis was conducted to determine factors that influenced the occurrence of delayed and nonreversal of defunctioning stoma, the rate of repeat stoma after closure, and the need for a permanent stoma in patients whose stomas were not initially defunctioning. RESULTS: A defunctioning stoma was created in 292 of 397 patients (74%); 12% of stomas were not reversible (33/279 that survived the operation >90 d); 11% (28/246) required a repeat stoma after stoma closure; 10% (10/105) of patients whose stomas were not initially defunctioning received a late permanent stoma. The overall rate of a permanent stoma was 18%. The main reasons for a permanent stoma were anastomosis-related complications and local recurrence. Risk factors for anastomosis-related complication were male gender, low tumor site, and tumor stage. Despite a significant reduction in local recurrence rates from 1997 to 2007, the rate of creating a permanent stoma did not change. CONCLUSIONS: The possibility of a permanent stoma should be considered when planning surgery for treating rectal cancer. It might be preferable in older patients, in poor condition and with more advanced rectal cancers, to consider an abdominoperineal resection or Hartmann procedure instead of a low anterior resection.

MDCT versus MRI assessment of tumor response after transarterial chemoembolization for the treatment of hepatocellular carcinoma.

The purpose of this study was to compare the ability of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) to evaluate treatment results after transarterial chemoembolization (TACE), with a special focus on the influence of Lipiodol on calculation of tumor necrosis according to EASL criteria. A total of 115 nodules in 20 patients (17 males, 3 females; 69.5 +/- 9.35 years) with biopsy-proven hepatocellular carcinoma were treated with TACE. Embolization was performed using a doxorubicin-Lipiodol emulsion (group I) or DC Beads loaded with doxorubicin (group II). Follow-up included triphasic contrast-enhanced 64-row MDCT (collimation, 0.625 mm; slice, 3 mm; contrast bolus, 120 ml iomeprol; delay by bolus trigger) and contrast-enhanced MRI (T1 native, T2 native; five dynamic contrast-enhanced phases; 0.1 mmol/kg body weight gadolinium-DTPA; slice thickness, 4 mm). Residual tumor and the extent of tumor necrosis were evaluated according to EASL. Contrast enhancement within tumor lesions was suspected to represent vital tumor. In the Lipiodol-based TACE protocol, MDCT underestimated residual viable tumor compared to MRI, due to Lipiodol artifacts (23.2% vs 47.7% after first, 11.9% vs 31.2% after second, and 11.4% vs 23.7% after third TACE; p = 0.0014, p < 0.001, and p < 0.001, respectively). In contrast to MDCT, MRI was completely free of any artifacts caused by Lipiodol. In the DC Bead-based Lipiodol-free TACE protocol, MRI and CT showed similar residual tumor and rating of treatment results (46.4% vs 41.2%, 31.9 vs 26.8%, and 26.0% vs 25.6%; n.s.). In conclusion, MRI is superior to MDCT for detection of viable tumor residuals after Lipiodol-based TACE. Since viable tumor tissue is superimposed by Lipiodol artifacts in MDCT, MRI is mandatory for reliable decision-making during follow-up after Lipiodol-based TACE protocols.

Ten-year follow-up of endovascular aneurysm treatment with Talent stent-grafts.

The purpose of this study was to evaluate the clinical results, complications, and secondary interventions during long-term follow-up after endovascular aneurysm repair (EVAR) and to investigate the impact of endoleak sizes on aneurysm shrinkage. From 1997 to March 2007, 127 patients (12 female, 115 male; age, 73.0 +/- 7.2 years) with abdominal aortic aneurysms were treated with Talent stent-grafts. Follow-up included clinical visits, contrast-enhanced MDCT, and radiographs at 3, 6, and 12 months and then annually. Results were analyzed with respect to clinical outcome, secondary interventions, endoleak rate and management, and change in aneurysm size. There was no need for primary conversion surgery. Thirty-day mortality was 1.6% (two myocardial infarctions). Procedure-related morbidity was 2.4% (paraplegia, partial infarction of one kidney, and inguinal bleeding requiring surgery). Mean follow-up was 47.7 +/- 34.2 months (range, 0-123 months). Thirty-nine patients died during follow-up; three of the deaths were related to aneurysm (aneurysm rupture due to endoleak, n = 1; secondary surgical reintervention n = 2). During follow-up, a total of 29 secondary procedures were performed in 19 patients, including 14 percutaneous procedures (10 patients) and 15 surgical procedures (12 patients), including 4 cases with late conversion to open aortic repair (stent-graft infection, n = 1; migration, endoleak, or endotension, n = 3). Overall mean survival was 84.5 +/- 4.7 months. Mean survival and freedom from any event was 66.7 +/- 4.5 months. MRI depicted significantly more endoleaks compared to MDCT (23.5% vs. 14.3%; P < 0.01). Patients in whom all aneurysm side branches were occluded prior to stent-grafting showed a significantly reduced incidence of large endoleaks. Endoleaks >10% of the aneurysm area were associated with reduced aneurysm shrinkage compared to no endoleaks or <10% endoleaks (Delta at 3 years, -1.8% vs. -12.0%; P < 0.05). In conclusion, endovascular aneurysm treatment with Talent stent-grafts demonstrated encouraging long-term results with moderate secondary intervention rates. Primary occlusion of all aortic side branches reduced the incidence of large endoleaks. Large endoleaks significantly impaired aneurysm shrinkage, whereas small endoleaks did not.

Gadofosveset-enhanced MR angiography of the pedal arteries in patients with diabetes mellitus and comparison with selective intraarterial DSA.

To compare gadofosveset-enhanced magnetic resonance angiography (MRA) of the pedal vasculature with selective intraarterial DSA. Eighteen patients with PAOD and type II diabetes were prospectively examined at 1.5 T. For contrast enhancement, 0.03 mmol/kg body weight gadofosveset was used. MR imaging consisted of dynamic and of high-resolution steady-state imaging. Selective digital subtraction angiography (DSA) was performed within 5 days and served as standard of reference. Image analysis was done by two observers. There were no differences between MRA and DSA regarding overall image quality. First-pass MRA detected significantly more patent vessel segments than did DSA (P<0.001, kappa=0.46). Interobserver agreement of MRA was very good with respect to the detection of patent vessel segments and the assessment of hemodynamically relevant stenoses (kappa=0.97 and 0.89, respectively). Steady-state imaging depicted significantly more patent metatarsal arteries than did dynamic imaging, and delineated inflammatory complications including osteomyelitis, soft-tissue abscesses, and fistulas related to the diabetic foot. Gadofosveset-enhanced MRA of the pedal vasculature proved to be superior to DSA. It offered a long imaging time window, and allowed for better depiction of the pedal outflow. Steady-state imaging delineated inflammatory complications associated with the diabetic foot.

Magnetic resonance imaging (MRI)-based indication for neoadjuvant treatment of rectal carcinoma and the surrogate endpoint CRM status.

AIM: Is it possible to reduce the frequency of neoadjuvant therapy for rectal carcinoma and nevertheless achieve a rate of more than 90% circumferential resection margin (CRM)-negative resection specimens by a novel concept of magnetic resonance imaging (MRI)-based therapy planning? MATERIALS AND METHODS: One hundred eighty-one patients from Berlin and Mainz, Germany, with primary rectal carcinoma, without distant metastasis, underwent radical surgery with curative intention. Surgical procedures applied were anterior resection with total mesorectal excision (TME) or partial mesorectal excision (PME; PME for tumours of the upper rectum) or abdominoperineal excision with TME. RESULTS: With MRI selection of the highest-risk cases, neoadjuvant therapy was given to only 62 of 181 (34.3%). The rate of CRM-negative resection specimens on histology was 170 of 181 (93.9%) for all patients, and in Berlin, only 1 of 93 (1%) specimens was CRM-positive. Patients selected for primary surgery had CRM-negative specimens on histology in 114 of 119 (95.8%). Those selected for neoadjuvant therapy had a lower rate of clear margin: 56 of 62 (90%). CONCLUSION: By applying a MRI-based indication, the frequency of neoadjuvant treatment with its acute and late adverse effects can be reduced to 30-35% without reduction of pathologically CRM-negative resection specimens and, thus, without the danger of worsening the oncological long-term results. This concept should be confirmed in prospective multicentre observation studies with quality assurance of MRI, surgery and pathology.

CT-guided vertebroplasty: analysis of technical results, extraosseous cement leakages, and complications in 500 procedures.

The aim of this study was to analyze the technical results, the extraosseous cement leakages, and the complications in our first 500 vertebroplasty procedures. Patients with osteoporotic vertebral compression fractures or osteolytic lesions caused by malignant tumors were treated with CT-guided vertebroplasty. The technical results were documented with CT, and the extraosseous cement leakages and periinterventional clinical complications were analyzed as well as secondary fractures during follow-up. Since 2002, 500 vertebroplasty procedures have been performed on 251 patients (82 male, 169 female, age 71.5 +/- 9.8 years) suffering from osteoporotic compression fractures (n = 217) and/or malignant tumour infiltration (n = 34). The number of vertebrae treated per patient was 1.96 +/- 1.29 (range 1-10); the numbers of interventions per patient and interventions per vertebra were 1.33 +/- 0.75 (range 1-6) and 1.01 +/- 0.10, respectively. The amount of PMMA cement was 4.5 +/- 1.9 ml and decreased during the 5-year period of investigation. The procedure-related 30-day mortality was 0.4% (1 of 251 patients) due to pulmonary embolism in this case. The procedure-related morbidity was 2.8% (7/251), including one acute coronary syndrome beginning 12 h after the procedure and one missing patellar reflex in a patients with a cement leak near the neuroformen because of osteolytic destruction of the respective pedicle. Additionally, one patient developed a medullary conus syndrome after a fall during the night after vertebroplasty, two patients reached an inadequate depth of conscious sedation, and two cases had additional fractures (one pedicle fracture, one rib fracture). The overall CT-based cement leak rate was 55.4% and included leakages predominantly into intervertebral disc spaces (25.2%), epidural vein plexus (16.0%), through the posterior wall (2.6%), into the neuroforamen (1.6%), into paravertebral vessels (7.2%), and combinations of these and others. During follow-up (15.2 +/- 13.4 months) the secondary fracture rate was 17.1%, including comparable numbers for vertebrae at adjacent and distant levels. The presence of intradiscal cement leaks was not associated with increased adjacent fracture rates. CT-guided vertebroplasty is safe and effective for treatment of vertebral compression fractures. CT-fluoroscopy provides an excellent control of the posterior vertebral wall. The number of cement leakages alone is not directly associated with clinical complications. However, even small volumes of pulmonary PMMA embolism might be responsible for the fatal outcome in cases with underlying cardiopulmonary insufficiency.

Assessment of tumor microcirculation with dynamic contrast-enhanced MRI in patients with esophageal cancer: initial experience.

PURPOSE: To investigate the feasibility and impact of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) on tumor characterization and response to radiochemotherapy (RCT) in patients with esophageal cancer. MATERIALS AND METHODS: A total of 48 patients underwent DCE-MRI to assess tumor microcirculation based on a two-compartment model function. Effects of RCT on kinetic parameters were studied in 12 patients with squamous cell carcinoma. RESULTS: Tumor microcirculation differs with respect to histological subtype: squamous cell carcinomas showed lower values of amplitude A (leakage space, P = 0.015) and higher contrast agent exchange rates (k(21), P = 0.225) compared with adenocarcinomas. RCT led to a significant decrease of the contrast agent exchange rate (P = 0.005), while amplitude A increased moderately after therapy (P = 0.136). CONCLUSION: DCE-MRI is feasible in patients with esophageal cancer, reveals therapeutic effects, and may thus be useful in therapy management and monitoring.

Chronic thromboembolic pulmonary hypertension - assessment by magnetic resonance imaging.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a severe disease that has been ignored for a long time. However, with the development of improved therapeutic modalities, cardiologists and thoracic surgeons have shown increasing interest in the diagnostic work-up of this entity. The diagnosis and management of chronic thromboembolic pulmonary hypertension require a multidisciplinary approach involving the specialties of pulmonary medicine, cardiology, radiology, anesthesiology and thoracic surgery. With this approach, pulmonary endarterectomy (PEA) can be performed with an acceptable mortality rate. This review article describes the developments in magnetic resonance (MR) imaging techniques for the diagnosis of chronic thromboembolic pulmonary hypertension. Techniques include contrast-enhanced MR angiography (ce-MRA), MR perfusion imaging, phase-contrast imaging of the great vessels, cine imaging of the heart and combined perfusion-ventilation MR imaging with hyperpolarized noble gases. It is anticipated that MR imaging will play a central role in the initial diagnosis and follow-up of patients with CTEPH.

A multicenter, site-independent, blinded study to compare the diagnostic accuracy of contrast-enhanced magnetic resonance angiography using 1.0M gadobutrol (Gadovist) to intraarterial digital subtraction angiography in body arteries.

PURPOSE: Prospective evaluation of diagnostic accuracy of single field-of-view contrast-enhanced MR Angiography (ceMRA) with 1.0M gadobutrol compared to intraarterial DSA in body arteries. MATERIALS AND METHODS: In an European multicenter study 179 patients underwent ceMRA and DSA. For each indication five prospectively defined vessel segments were evaluated by local investigators onsite and by three site-independent blinded readers (BR) independently. RESULTS: The agreement between ceMRA and DSA diagnosis was statistically significant in the onsite (96.6%) and blinded reader (86.6-90.2%) evaluation. Sensitivity, specificity, accuracy, positive (PPV) and negative predictive values (NPV) for detection of relevant stenosis (>50%) were calculated for the right and left internal carotid arteries, and common and external iliac arteries: Sensitivity was 95-98% (onsite) and 76-96% (BR), specificity 94-96% (onsite) and 86-94% (BR), accuracy 96% (onsite) and 87-93% (BR), NPV 98-99% (onsite) and 84-98% (BR), and PPV 79-93% (onsite) and 44-91% (BR), respectively. CONCLUSION: CeMRA of body arteries using 1.0M gadobutrol provides diagnostic information comparable to intraarterial DSA.