Feasibility and safety of ADAPT in acute distal posterior cerebral artery occlusions.

PURPOSE: The direct aspiration first pass technique (ADAPT) is an effective and safe endovascular treatment for distal medium vessel occlusions (DMVO) of the anterior circulation. Clinical experience with ADAPT in the distal posterior circulation, however, is still limited and published data is scarce. In this original work, feasibility, safety and efficacy of ADAPT with distal access catheters (DAC) for treatment of acute distal posterior cerebral artery occlusions (DPCAOs) is evaluated. METHOD: All acute ischemic stroke patients between 2017 and 2022 with primary or secondary DPCAOs in the P2 or P3 segment, that underwent thrombectomy of the DPACO using ADAPT with DACs as frontline therapy, were identified. Demographic data, recanalization rates, procedural safety, and clinical outcome were assessed. RESULTS: Twenty-four patients with primary (n = 6) or secondary (n = 18) DPCAOs (P2: 21/24; P3: 3/24) were included. Median NIHSS score at admission was 14.5 (IQR 9.5). In all cases, the DPCAO could be reached with the DAC. Successful revascularization (DMVO-p-TICI ≥ 2b) with ADAPT was achieved in 79.2% (19/24), including a first pass effect of 62.5% (15/24), leading to complete recanalization (DMVO-p-TICI 3). Median number of passes was 1 (range 1-2). No complications related to distal PCA aspiration thrombectomy occurred. Median NIHSS and mRS scores at discharge were 4 (IQR 8) and 3 (IQR 2), respectively. CONCLUSIONS: ADAPT appears to be feasible, safe and effective for the treatment of acute DPCAOs in the setting of different occlusion patterns. High revascularization rates without procedural complications can be achieved. Further studies are needed to consolidate these results.

Single-energy versus dual-energy imaging during CT-guided biopsy using dedicated metal artifact reduction algorithm in an in vivo pig model.

PURPOSE: To evaluate dual-energy CT (DE) and dedicated metal artifact reduction algorithms (iMAR) during CT-guided biopsy in comparison to single-energy CT (SE). METHODS: A trocar was placed in the liver of six pigs. CT acquisitions were performed with SE and dose equivalent DE at four dose levels(1.7-13.5mGy). Iterative reconstructions were performed with and without iMAR. ROIs were placed in four positions e.g. at the trocar tip(TROCAR) and liver parenchyma adjacent to the trocar tip(LIVER-1) by two independent observers for quantitative analysis using CT numbers, noise, SNR and CNR. Qualitative image analysis was performed regarding overall image quality and artifacts generated by iMAR. RESULTS: There were no significant differences in CT numbers between DE and SE at TROCAR and LIVER-1 irrespective of iMAR. iMAR significantly reduced metal artifacts at LIVER-1 for all exposure settings for DE and SE(p = 0.02-0.04), but not at TROCAR. SNR, CNR and noise were comparable for DE and SE. SNR was best for high dose levels of 6.7/13.5mGy. Mean difference in the Blant-Altman analysis was -8.43 to 0.36. Cohen's kappa for qualitative interreader-agreement was 0.901. CONCLUSIONS: iMAR independently reduced metal artifacts more effectively and efficiently than CT acquisition in DE at any dose setting and its application is feasible during CT-guided liver biopsy.

Back to the Future: Lipiodol in Lymphography-From Diagnostics to Theranostics.

Lipiodol is an iodinated poppy seed oil first synthesized in 1901. Originally developed for therapeutic purposes, it has mainly become a diagnostic contrast medium since the 1920s. At the end of the 20th century, Lipiodol underwent a transition back to a therapeutic agent, as exemplified by its increasing use in lymphangiography and lymphatic interventions. Nowadays, indications for lymphangiography include chylothorax, chylous ascites, chyluria, and peripheral lymphatic fistula or lymphoceles. In these indications, Lipiodol alone has a therapeutic effect with clinical success in 51% to 100% of cases. The 2 main access sites to the lymphatic system for lymphangiography are cannulation of lymphatic vessels in the foot (transpedal) and direct puncture of (mainly inguinal) lymph nodes (transnodal). In case of failure of lymphangiography alone to occlude the leaking lymphatic vessel as well as in indications such as protein-losing enteropathy, postoperative hepatic lymphorrhea, or plastic bronchitis, lymphatic vessels can also be embolized directly by injecting a mixture of Lipiodol and surgical glues (most commonly in thoracic duct embolization). The aim of this article is to review the historical role of Lipiodol and the evolution of its clinical application in lymphangiography over time until the current state-of-the-art lymphatic imaging techniques and interventions.

Semi-automated computed tomography Volumetry can predict hemihepatectomy specimens' volumes in patients with hepatic malignancy.

BACKGROUND: One of the major causes of perioperative mortality of patients undergoing major hepatic resections is post-hepatectomy liver failure (PHLF). For preoperative appraisal of the risk of PHLF it is important to accurately predict resectate volume and future liver remnant volume (FLRV). The objective of our study is to prospectively evaluate the accuracy of hemihepatectomy resectate volumes that are determined by computed tomography volumetry (CTV) when compared with intraoperatively measured volumes and weights as gold standard in patients undergoing hemihepatectomy. METHODS: Twenty four patients (13 women, 11 men) scheduled for hemihepatectomy due to histologically proven primary or secondary hepatic malignancies were included in our study. CTV was performed using a semi-automated module (S, hereinafter) (syngo.CT Liver Analysis VA30, Siemens Healthcare, Germany). Conversion factors between CT volumes on the one side and intraoperative volumes and weights on the other side were calculated using the method of least squares. Absolute and relative disagreements between CT volumes and intraoperative volumes were determined. RESULTS: A conversion factor of c = 0.906 most precisely predicted intraoperative volumes of exsanguinated hemihepatectomy specimens from CT volumes in all patients with mean absolute and relative disagreements between CT volumes and intraoperative volumes of 57 ml and 6.3%. The use of operation-specific conversion factors yielded even better results. CONCLUSIONS: CTV performed with S accurately predicts intraoperative volumes of hemihepatectomy specimens when applying conversion factors which compensate for exsanguination. This allows to precisely estimate the FLRV and thus minimize the risk of PHLF in patients undergoing major hepatic resections.

Radiation Exposure During Uterine Fibroid Embolization (UFE): A Confounder-Controlled Comparison Between a State-of-the-Art Angiography Unit and a Conventional Angiography unit.

PURPOSE: To compare radiation exposure of a state-of-the-art and a conventional angiography unit in patients undergoing uterine fibroid embolization (UFE). MATERIALS AND METHODS: Between January 2009 and December 2016, 286 patients underwent UFE in our Interdisciplinary Fibroid Center. The inclusion criteria for this retrospective analysis were first-time transarterial embolization for symptomatic fibroids, bilateral embolization, procedures applying a state-of-the-art (Group 1) or a conventional angiography unit (Group 2), and bilateral technical success with an adequate embolization endpoint after the injection of microspheres. Study endpoints included radiation exposure, major complications, morphological success (MRI), and clinical success (questionnaire on quality-of-life). Propensity score matching controlled for confounders. RESULTS: The inclusion criteria were met by 58 (Group 1) and 177 (Group 2) patients. After propensity score matching, there was no significant difference between Group 1 (n = 46) and Group 2 (n = 92) regarding age, body-mass index, volume of the dominant fibroid and the uterus, fluoroscopy time, and amount of embolic agent (p ≥ 0.10 each). The dose-area product was significantly lower in Group 1 than in Group 2 (1159.0 cGycm2 vs. 3123.5 cGycm2; p < 0.001), while major complication rates (both groups 0 %) and dominant fibroid devascularization (both groups 100 %) were equal (p > 0.99). There were no significant differences between both groups regarding shrinkage of the dominant fibroid and the uterus and no relevant differences regarding patient-reported quality-of-life. CONCLUSION: A state-of-the-art angiography unit has the potential to reduce radiation exposure in patients undergoing UFE without increasing the risk of major complications and with comparably high morphological and clinical success. KEY POINTS: · A state-of-the-art angiography unit potentially reduces radiation exposure in patients undergoing UFE.. · Reduced radiation exposure does not seem to negatively influence the rate of major complications.. · Reduced exposure does not seem to negatively affect morphological and clinical success.. CITATION FORMAT: · Sommer C, Voigt W, Oliger MK et al. Radiation Exposure During Uterine Fibroid Embolization (UFE): A Confounder-Controlled Comparison Between a State-of-the-Art Angiography Unit and a Conventional Angiography unit. Fortschr Röntgenstr 2018; 190: 250 - 258.

Treatment Failure After Image-Guided Percutaneous Radiofrequency Ablation (RFA) of Renal Tumors - A Systematic Review with Description of Type, Frequency, Risk Factors and Management.

Background Radiofrequency ablation (RFA) is an established treatment for small renal tumors. The objective of this review is to systematically assess the type, frequency, risk factors and management of treatment failure after image-guided percutaneous RFA of renal tumors. Method 10 studies (967 patients, 1033 tumors) with a mean/median follow-up of ≥ 30 months were systematically identified and analyzed. Results and Conclusion Image-guided percutaneous RFA of localized renal tumors is very effective. The most common type of treatment failure is residual unablated tumor (5.9 %), followed by local tumor progression (4.7 %). De novo tumors in the kidneys occur in 1.3 % of cases and extra-renal metastases in 2.0 %. Local tumor progression, de novo tumors in the kidneys and extra-renal metastases occur predominantly later than 12 months after initial RFA. Tumor size > 3 cm and central tumor location are the major risk factors for treatment failure. In the case of treatment failure, repeated RFA shows high success rates (86.3 % for residual unablated tumors and 87.5 % for local tumor progression). Key Points: · Treatment failure can be subdivided into residual unablated tumor and local tumor progression.. · Residual unablated tumor occurs in 5.9 % of cases.. · Local tumor progression occurs in 4.7 % of cases.. · Tumor size and location are the major risk factors for treatment failure.. · Repeated RFA is effective and commonly used for management.. Citation Format · Vollherbst D, Bertheau R, Kauczor H et al. Treatment Failure After Image-Guided Percutaneous Radiofrequency Ablation (RFA) of Renal Tumors - A Systematic Review with Description of Type, Frequency, Risk Factors and Management. Fortschr Röntgenstr 2017; 189: 219 - 227.

Evaluation of the plasmatic and parenchymal elution kinetics of two different irinotecan-loaded drug-eluting embolics in a pig model.

PURPOSE: To evaluate and compare irinotecan elution kinetics of two drug-eluting embolic agents in a porcine model. MATERIALS AND METHODS: Embolization of the left liver lobe was performed in 16 domestic pigs, with groups of two receiving 1 mL of DC Bead M1 (70-150 µm) or Embozene TANDEM (75 µm) loaded with 50 mg irinotecan. Irinotecan plasma levels were measured at 0, 10, 20, 30, 60, 120, 180, and 240 minutes after completed embolization and at the time of euthanasia (24 h, 48 h, 72 h, or 7 d). Liver tissue samples were taken to measure irinotecan tissue concentrations. RESULTS: The highest irinotecan plasma concentrations of both embolic agents were measured 10 and 20 minutes after embolization, and concentrations were significantly higher for DC Bead M1 versus Embozene TANDEM (P = .0019 and P = .0379, respectively). At 48 hours and later follow-up, no irinotecan was measurable in the plasma. For both embolic agents, the highest irinotecan tissue concentration was found after 24 hours and decreased in a time-dependent manner at later follow-up intervals. Additionally, SN-38 tissue levels for both agents were therapeutic at 24 hours, with therapeutic levels of SN-38 at 48 hours in one liver embolized with TANDEM particles. Histopathologic analysis revealed ischemic, inflammatory, and fibrotic tissue reactions. CONCLUSIONS: Irinotecan is measurable in plasma and hepatic tissue after liver embolization with both types of irinotecan-eluting embolic agents. DC Bead M1 shows early burst elution kinetics, whereas Embozene TANDEM has a lower and slower release profile. The initial burst is significantly greater after embolization with DC Bead M1 than with Embozene TANDEM.

Accuracy of estimation of graft size for living-related liver transplantation: first results of a semi-automated interactive software for CT-volumetry.

OBJECTIVES: To evaluate accuracy of estimated graft size for living-related liver transplantation using a semi-automated interactive software for CT-volumetry. MATERIALS AND METHODS: Sixteen donors for living-related liver transplantation (11 male; mean age: 38.2±9.6 years) underwent contrast-enhanced CT prior to graft removal. CT-volumetry was performed using a semi-automated interactive software (P), and compared with a manual commercial software (TR). For P, liver volumes were provided either with or without vessels. For TR, liver volumes were provided always with vessels. Intraoperative weight served as reference standard. Major study goals included analyses of volumes using absolute numbers, linear regression analyses and inter-observer agreements. Minor study goals included the description of the software workflow: degree of manual correction, speed for completion, and overall intuitiveness using five-point Likert scales: 1--markedly lower/faster/higher for P compared with TR, 2--slightly lower/faster/higher for P compared with TR, 3--identical for P and TR, 4--slightly lower/faster/higher for TR compared with P, and 5--markedly lower/faster/higher for TR compared with P. RESULTS: Liver segments II/III, II-IV and V-VIII served in 6, 3, and 7 donors as transplanted liver segments. Volumes were 642.9±368.8 ml for TR with vessels, 623.8±349.1 ml for P with vessels, and 605.2±345.8 ml for P without vessels (P<0.01). Regression equations between intraoperative weights and volumes were y = 0.94x+30.1 (R2 = 0.92; P<0.001) for TR with vessels, y = 1.00x+12.0 (R2 = 0.92; P<0.001) for P with vessels, and y = 1.01x+28.0 (R2 = 0.92; P<0.001) for P without vessels. Inter-observer agreement showed a bias of 1.8 ml for TR with vessels, 5.4 ml for P with vessels, and 4.6 ml for P without vessels. For the degree of manual correction, speed for completion and overall intuitiveness, scale values were 2.6±0.8, 2.4±0.5 and 2. CONCLUSIONS: CT-volumetry performed with P can predict accurately graft size for living-related liver transplantation while improving workflow compared with TR.

Hepatic artery stent-grafts for the emergency treatment of acute bleeding.

PURPOSE: We evaluated the technical success and clinical efficacy of stent-graft implantation for the emergency management of acute hepatic artery bleeding. METHODS: Between January 2010 and July 2013, 24 patients with hemorrhage from the hepatic artery were scheduled for emergency implantation of balloon expandable stent-grafts. The primary study endpoints were technical and clinical success, which were defined as successful stent-graft implantation with sealing of the bleeding site at the end of the procedure, and cessation of clinical signs of hemorrhage. The secondary study endpoints were complications during the procedure or at follow-up and 30-day mortality rate. RESULTS: In 23 patients, hemorrhage occurred after surgery, and in one patient hemorrhage occurred after trauma. Eight patients had sentinel bleeding. In most patients (n=16), one stent-graft was implanted. In six patients, two overlapping stent-grafts were implanted. The stent-grafts had a target diameter between 4mm and 7 mm. Overall technical success was 88%. The bleeding ceased after stent-graft implantation in 21 patients (88%). The mean follow-up was 137 ± 383 days. In two patients, re-bleeding from the hepatic artery occurred during follow-up after 4 and 29 days, respectively, which could be successfully treated by endovascular therapy. The complication rate was 21% (minor complication rate 4%, major complication rate 17%). The 30-day mortality rate was 21%. CONCLUSIONS: Implantation of stent-grafts in the hepatic artery is an effective emergency therapy and has a good technical success rate for patients with acute arterial hemorrhage.

Emergency embolization for the treatment of acute hemorrhage from intercostal arteries.

To evaluate embolotherapy for the emergency management of acute bleeding from intercostal arteries. Between October 2003 and August 2012, 19 consecutive patients with hemorrhage from intercostal arteries were scheduled for emergency embolization. The primary study endpoints were technical and clinical success, which were defined as angiographic cessation of bleeding, and cessation of clinical signs of hemorrhage. The secondary study endpoints were periprocedural complications and 30-day mortality rate. In most patients (74 %), hemorrhage was caused by iatrogenic procedures with subsequent intercostal artery laceration. One of the patients was treated twice for recurrent hemothorax caused by a new intercostal artery pseudoaneurysm 7.5 years after the initial procedure. Thus, 20 procedures were performed in these 19 patients. Overall technical success was 85 %. In six patients, no embolization of the "backdoor" was feasible, and in two of these patients additional embolization of other intercostal arteries was necessary to prevent hemorrhage via collateral vessels. Clinical signs of hemorrhage ceased after embolotherapy in 16 of 20 procedures (clinical success 80 %). The mean follow-up was 358.7 ± 637.1 days. One minor procedure-related complication occurred. The 30-day mortality rate was 21 %, however, this was unrelated to intercostal artery hemorrhage. Embolotherapy is an effective emergency therapy for patients with acute hemorrhage from intercostal arteries. Especially if embolization of the backdoor is not feasible, collateral supply via other intercostal arteries should be either ruled out or embolized to prevent ongoing hemorrhage. Despite successful embolotherapy, a majority of patients underwent surgery during follow-up to remove the symptomatic hematoma.

Therapeutic lymphangiography and CT-guided sclerotherapy for the treatment of refractory lymphatic leakage.

PURPOSE: To evaluate therapeutic lymphangiography and computed tomography (CT)-guided sclerotherapy for the treatment of refractory inguinal, pelvic, abdominal, and thoracic lymphatic leakage. MATERIALS AND METHODS: Between January 2008 and April 2011, 18 patients with refractory lymphatic leakage were treated with therapeutic lymphangiography. Additionally, 10 of these 18 patients underwent CT-guided sclerotherapy with injection of ethanol at the site of the leakage. In the delayed sclerotherapy group (n = 5), the sclerotherapy procedure was performed when the leak persisted after therapeutic lymphangiography. In the immediate sclerotherapy group (n = 5), sclerotherapy was performed on the same day as lymphangiography. The sites of the lymphatic leakage were as follows: inguinal leakage in 8 patients, pelvic leakage in 4 patients, abdominal leakage in 2 patients, and thoracic leakage in 4 patients. Data collected included technical success, clinical success, and procedural complications. RESULTS: Lymphangiography was technically successful in all patients. In eight patients undergoing therapeutic lymphangiography alone, the clinical success rate was 75%, and the drainage catheter could be removed in six patients after the treatment. Lymphangiography followed by immediate sclerotherapy was clinically successful in four of five patients. Lymphangiography combined with delayed sclerotherapy was clinically successful in three of five patients. Overall, the clinical success rate was 72% (13 of 18 patients). One minor complication occurred. CONCLUSIONS: Therapeutic lymphangiography alone or in combination with CT-guided sclerotherapy is a promising treatment option for the management of refractory lymphatic leakage.

Efficacy and safety of percutaneous microwave coagulation therapy followed by 125I seed brachytherapy for VX2 hepatic tumors in a rabbit model.

The aim of this study was to evaluate the efficacy and safety of percutaneous microwave coagulation therapy (PMCT) followed by 125I seed brachytherapy for VX2 liver cancer in rabbits. Eighty New Zealand rabbits were injected with suspensions of VX2 tumor cells to create an animal model. The rabbits were randomly divided into 4 groups (n=20); the control, PMCT, 125I seed brachytherapy and combination groups. Group A was treated with PMCT at 40 W for 120 sec, group B was treated with 125I seed brachytherapy and group C was treated with PMCT followed by 125I seed brachytherapy. Group D were not treated and served as the control group. At 21 days after treatment, the rabbits were sacrificed for pathological assessment. The complete tumor necrosis rate was 19 out of 20 tumors (95%) in group C, 6 (30%) in group A, 0 (0%) in group B and 0 (0%) in the control group. The complete tumor necrosis rate was observed to be significantly different between groups C and A, and between groups C and B (P<0.01). No intraheptic metastasis occurred in group C, compared with an incidence of 7 (35%) in group A, 2 (10%) in group B and 20 (100%) in the control group. Between groups C and A, and between groups C and D, the intraheptic metastasis rate was statistically significant (P<0.01). PMCT followed by 125I seed brachytherapy increased the rate of carcinoma necrosis and decreased carcinoma metastasis in the VX2 rabbit model. This combined treatment is a safe, effective and minimally invasive therapeutic option for liver cancer.

Microwave ablation in porcine livers applying 5-minute protocols: influence of deployed energy on extent and shape of coagulation.

PURPOSE: To evaluate the influence of deployed energy on extent and shape of microwave (MW)-induced coagulation in porcine livers applying 5-minute protocols. MATERIALS AND METHODS: MW ablations (n = 25) were performed in ex vivo porcine livers (n = 8). Ablation time was 5 minutes. Five study groups were defined, each with different power output: I, 20 W (n = 5); II, 40 W (n = 5); III, 60 W (n = 5); IV, 80 W (n = 5); and V, 105 W (n = 5). Extent and shape of white coagulation was evaluated macroscopically, including short diameter, volume, front margin, coagulation center (distance between center of short diameter of coagulation and applicator tip), and ellipticity index (short diameter/long diameter). Deployed energy was also analyzed. RESULTS: Short diameter and volume were significantly different (P<.001 and P<.001) between the groups: I, 23.0 mm and 11.1 cm(3); II, 12.4 mm and 12.4 cm(3); III, 27.0 mm and 17.6 cm(3); IV, 31.0 mm and 29.2 cm(3); and V, 35.0 mm and 42.3 cm(3). Front margin and coagulation center were also significantly different (P<.05 and P<.001): I, 6.0 mm and 13.0 mm; II, 8.0 mm and 11.0 mm; III, 8.0 mm and 14.0 mm; IV, 8.0 mm and 18.0 mm; and V, 10.0 mm and 19.0 mm. Ellipticity index was not significantly different. Deployed energy was significantly different (P<.001): I, 5.7 kJ; II, 11.0 kJ; III, 15.5 kJ; IV, 21.6 kJ; and V, 26.6 kJ. CONCLUSIONS: Extent, but not shape, of MW-induced coagulation depends on the deployed energy. Applying the protocols described in this study, significantly different coagulation volumes can be created with an ablation time of 5 minutes but different power output.

Multimodal visibility of a modified polyzene-F-coated spherical embolic agent for liver embolization: feasibility study in a porcine model.

PURPOSE: To evaluate multimodal visibility of modified currently available microspheres on radiography, magnetic resonance (MR) imaging, and computed tomography (CT) in a porcine liver model. MATERIALS AND METHODS: Livers of four pigs were embolized with two sizes (100 µm ± 25 and 700 µm ± 50) of modified Embozene Microspheres embedded with different densities of barium sulfate and iodine as radiopaque materials (intensity groups A-C, with increasing intensity from A to C for 100 µm and intensities A and C for 700 µm) and iron oxide as magnetic substance for MR imaging visibility. Pigs embolized with currently available Embozene Microspheres served as control groups. Pre- and postinterventional MR imaging (T1- and T2-weighted) and CT were performed. Qualitative and quantitative (ie, determination of signal-to-noise ratio [SNR]) particle visibility was evaluated on radiography, MR imaging, and CT. RESULTS: Modified particles of both sizes were visible on radiography, MR imaging, and CT. Particles in the control group were not visible. For modified particles of both sizes, SNRs measured on MR imaging decreased significantly after embolization (eg, cluster analysis of group A, 100 µm ± 50 particles, T1-weighted, -74.6% ± 3.4; P = .03). For modified particles of both sizes, SNR measured on CT increased significantly after embolization (eg, cluster analysis of group A, 700 µm ± 25 particles, +54.3% ± 13.5; P = .03). CONCLUSIONS: Modification of currently available Embozene Microspheres was successful, with multimodal visibility on radiography, MR imaging, and CT in porcine liver. In the future, this might improve procedure accuracy and allow monitoring, control, and improvement of embolotherapy during and after the procedure.

Superselective embolization for the management of postpancreatectomy hemorrhage: a single-center experience in 25 patients.

PURPOSE: To evaluate the efficacy of superselective embolization in patients with late postpancreatectomy hemorrhage (PPH). MATERIALS AND METHODS: Between January 2002 and July 2010, 25 patients (19 men) with suspected late PPH (> 24 hours after the operation) were evaluated. The primary study endpoint was technical success, defined as complete angiographic occlusion of the site of hemorrhage. Secondary study endpoints were multidetector computed tomography (CT) and angiographic findings regarding accurate detection of the site of hemorrhage, persistence of hemorrhage, or occurrence of rebleeding during clinical follow-up. RESULTS: Multidetector CT was performed before the intervention in 17 (68%) patients with detection of hemorrhage in 15 (88%) patients. The site of hemorrhage was detected in 23 (92%) of 25 patients by angiography. Four (17%) patients required a superselective catheter position. Embolization was attempted in all 23 patients with angiographically visible hemorrhage. In three (13%) patients, embolization could not be performed because a superselective catheter position was not achievable. Technical success was 83% (19 patients). In one patient, hemostasis was not achieved by embolization. Minor complications occurred in three (13%) patients. No major complications occurred. Three patients with technically successful embolization (16%) had a second episode of bleeding during follow-up and required repeat embolization 5-23 days after the procedure. The 30-day mortality rate was 20%. CONCLUSIONS: Superselective embolization is a technically and clinically effective procedure in patients with late PPH. Diagnostic angiography should be performed with a superselective microcatheter position to detect the bleeding site effectively.

The use of balloon-expandable stent grafts for the management of acute arterial bleeding.

PURPOSE: To evaluate the efficacy and safety of balloon-expandable stent grafts in the emergency treatment of acute arterial hemorrhage. MATERIALS AND METHODS: Between July 2008 and December 2009, 15 patients with acute arterial hemorrhage from inflammatory vessel erosion or pseudoaneurysms (n = 9), noninflammatory pseudoaneurysms (n = 3), or iatrogenic vessel injury (n = 3) were treated with emergency stent graft implants. The primary study endpoints to determine treatment efficacy and safety were survival, complication rates, and freedom from recurrent hemorrhaging or reintervention. The secondary study endpoints were technical and clinical success. RESULTS: The survival rate was 73% with a mean follow-up of 119 days ± 220. The complication rate was 20%. The procedure was technically successful in 13 of 15 (87%) patients. One endoleak persisted and led to a reintervention rate of 7%. The bleeding ceased immediately after stent graft implantation in 14 patients. CONCLUSIONS: Implantation of balloon-expandable stent grafts is a safe and effective emergency treatment for acute arterial hemorrhage from visceral and peripheral vessels.

Risk factors and clinical management of haemorrhage after open nephron-sparing surgery.

OBJECTIVE: To identify risk factors for relevant haemorrhage after open nephron-sparing surgery (NSS) for renal cell carcinoma, and to evaluate its clinical management. PATIENTS AND METHODS: We evaluated bleeding complications after open NSS in 196 consecutive cases (193 patients) at our institution. The median (range) age of the patients was 64 (3-91) years and the tumour diameter was 2.7 (0.5-11.8) cm. Sex, age, body mass index, imperative vs elective indication, year of surgery, multifocality, tumour diameter and malignant vs benign pathology were tested exploratively and significant variables entered in a multivariate model. The clinical management of haemorrhage after NSS was analysed. RESULTS: Bleeding required conservative (six), interventional (six) or surgical (three) therapy in 15 of the 196 cases (8%). Imperative indication (P= 0.043) and multifocality (P= 0.039) were independent risk factors in a multivariate model. Compared with superselective percutaneous transarterial embolization (TAE), surgery as a primary therapeutic option was more likely within 24 h after NSS (P= 0.012). Bleeding was finally controlled in all patients, while the kidney was preserved in 11 patients. There was only a minor decline of renal function at the 3-month follow-up. CONCLUSIONS: We identified multifocal tumours and imperative indication as risk factors for haemorrhage after NSS. The management was very successful, relying on TAE as an effective and safe treatment for bleeding after NSS. In rare cases of severe bleeding surgical exploration is unavoidable, with a lower chance of kidney preservation.

Immunohistochemical characterization of specific inflammatory tissue reactions following embolization with four different spherical agents in the minipig kidney model.

PURPOSE: To evaluate the immunohistochemical inflammatory reaction after porcine renal embolization with the new spherical embolic agent Embozene and to compare it with other spherical embolic agents. MATERIALS AND METHODS: After superselective porcine renal embolization (40 pigs) with different sizes of embolic agents (Embozene, Embosphere, Bead Block, Contour SE), tissue arrays were obtained (size ranges, 40-120 microm, 100-300 microm, 500-700 microm, 700-900 microm). After immunostaining for CD subtyping (CD45 and CD68) and cytokines (C-reactive protein [CRP] and interleukin-1 beta), a semiquantitative immunoreactivity score was calculated for each marker: intensity of staining was scored between 0 (negative) and 3 (intensive) and extent of staining between 0 and 4 (>80%), indicating the percentage of positive staining. The intensity score (0-3) was multiplied by the extent of staining score (0-4), resulting in a semiquantitative immunoreactivity score (0-12). RESULTS: Analysis of cellular expression profiles (ie, CD45, CD68) revealed a significantly higher inflammatory score 4 weeks after embolization with Embosphere 100-300 microm particles than after embolization with Embozene, Bead Block, and Contour SE. After 12 weeks, the Embosphere 100-300 microm score decreased. Analysis of CRP expression showed similar results, with a significantly higher score 4 weeks after embolization with Embosphere 100-300 microm. In the size class used most frequently for uterine artery emboliation (500-700 microm), all scores were low (<2.5) and there was no significant difference among particle types. CONCLUSIONS: Pronounced immunomarker expression was seen 4 weeks after embolization with small Embosphere particles. However, in general, modern spherical embolic agents cause a fairly low level of inflammatory reaction. In the present experimental setting, which is highly sensitive for specific tissue-to-agent reactivity, Embozene presented with low inflammatory results.