Adjuvant holmium-166 radioembolization after radiofrequency ablation in early-stage hepatocellular carcinoma patients: a dose-finding study (HORA EST HCC trial).

PURPOSE: The aim of this study was to investigate the biodistribution of (super-)selective trans-arterial radioembolization (TARE) with holmium-166 microspheres (166Ho-MS), when administered as adjuvant therapy after RFA of HCC 2-5 cm. The objective was to establish a treatment volume absorbed dose that results in an absorbed dose of ≥ 120 Gy on the hyperemic zone around the ablation necrosis (i.e., target volume). METHODS: In this multicenter, prospective dose-escalation study in BCLC early stage HCC patients with lesions 2-5 cm, RFA was followed by (super-)selective infusion of 166Ho-MS on day 5-10 after RFA. Dose distribution within the treatment volume was based on SPECT-CT. Cohorts of up to 10 patients were treated with an incremental dose (60 Gy, 90 Gy, 120 Gy) of 166Ho-MS to the treatment volume. The primary endpoint was to obtain a target volume dose of ≥ 120 Gy in 9/10 patients within a cohort. RESULTS: Twelve patients were treated (male 10; median age, 66.5 years (IQR, [64.3-71.7])) with a median tumor diameter of 2.7 cm (IQR, [2.1-4.0]). At a treatment volume absorbed dose of 90 Gy, the primary endpoint was met with a median absorbed target volume dose of 138 Gy (IQR, [127-145]). No local recurrences were found within 1-year follow-up. CONCLUSION: Adjuvant (super-)selective infusion of 166Ho-MS after RFA for the treatment of HCC can be administered safely at a dose of 90 Gy to the treatment volume while reaching a dose of ≥ 120 Gy to the target volume and may be a favorable adjuvant therapy for HCC lesions 2-5 cm. TRIAL REGISTRATION: Clinicaltrials.gov NCT03437382 . (registered: 19-02-2018).

Improving MRI-based dosimetry for holmium-166 transarterial radioembolization using a nonrigid image registration for voxelwise Δ R 2 ∗ $\Delta R_2

BACKGROUND: Transarterial radioembolization (TARE) is a treatment modality for liver tumors during which radioactive microspheres are injected into the hepatic arterial system. These microspheres distribute throughout the liver as a result of the blood flow until they are trapped in the arterioles because of their size. Holmium-166 (166 Ho)-loaded microspheres used for TARE can be visualized and quantified with MRI, as holmium is a paramagnetic metal and locally increases the transverse relaxation rate R 2 ∗ $R_2^*$ . The current 166 Ho quantification method does not take regional differences in baseline R 2 ∗ $R_2^*$ values (such as between tumors and healthy tissue) into account, which intrinsically results in a systematic error in the estimated absorbed dose distribution. As this estimated absorbed dose distribution can be used to predict response to treatment of tumors and potential toxicity in healthy tissue, a high accuracy of absorbed dose estimation is required. PURPOSE: To evaluate pre-existing differences in R 2 ∗ $R_2^*$ distributions between tumor tissue and healthy tissue and assess the feasibility and accuracy of voxelwise subtraction-based Δ R 2 ∗ $\Delta R_2^*$ calculation for MRI-based dosimetry of holmium-166 transarterial radioembolization (166 Ho TARE). METHODS: MRI data obtained in six patients who underwent 166 Ho TARE of the liver as part of a clinical study was retrospectively evaluated. Pretreatment differences in R 2 ∗ $R_2^*$ distributions between tumor tissue and healthy tissue were characterized. Same-day pre- and post-treatment R 2 ∗ $R_2^*$ maps were aligned using a deformable registration algorithm and subsequently subtracted to generate voxelwise Δ R 2 ∗ $\Delta R_2^*$ maps and resultant absorbed dose maps. Image registration accuracy was quantified using the dice similarity coefficient (DSC), relative overlay (RO), and surface dice (≤4 mm; SDSC). Voxelwise subtraction-based absorbed dose maps were quantitatively (root-mean-square error, RMSE) and visually compared to the current MRI-based mean subtraction method and routinely used SPECT-based dosimetry. RESULTS: Pretreatment R 2 ∗ $R_2^*$ values were lower in tumors than in healthy liver tissue (mean 36.8 s-1 vs. 55.7 s-1 , P = 0.004). Image registration improved the mean DSC of 0.83 (range: 0.70-0.88) to 0.95 (range: 0.92-0.97), mean RO of 0.71 (range 0.53-0.78) to 0.90 (range: 0.86-0.94), and mean SDSC ≤4 mm of 0.47 (range: 0.28-0.67) to 0.97 (range: 0.96-0.98). Voxelwise subtraction-based absorbed dose maps yielded a higher tumor-absorbed dose (median increase of 9.0%) and lower healthy liver-absorbed dose (median decrease of 13.8%) compared to the mean subtraction method. Voxelwise subtraction-based absorbed dose maps corresponded better to SPECT-based absorbed dose maps, reflected by a lower RMSE in three of six patients. CONCLUSIONS: Voxelwise subtraction presents a robust alternative method for MRI-based dosimetry of 166 Ho microspheres that accounts for pre-existing R 2 ∗ $R_2^*$ differences, and appears to correspond better with SPECT-based dosimetry compared to the currently implemented mean subtraction method.

CXCR4-directed [68Ga]Ga-PentixaFor PET/CT versus adrenal vein sampling performance: a study protocol for a randomised two-step controlled diagnoStic Trial Ultimately comparing hypertenSion outcome in primary aldosteronism (CASTUS).

INTRODUCTION: Primary aldosteronism (PA) is the most common form of secondary hypertension. It is caused by overproduction of aldosterone by either a unilateral aldosterone-producing adenoma (APA) or by bilateral adrenal hyperplasia (BAH). Distinction is crucial, because PA is cured by adrenalectomy in APA and is treated by mineralocorticoid receptor antagonists in BAH. The distinction is currently made by adrenal vein sampling (AVS). AVS is a costly, invasive and complex technical procedure with limited availability and is not superior in terms of outcomes to CT scan-based diagnosis. Thus, there is a need for a cheaper, non-invasive and readily available diagnostic tool in PA. We propose a new diagnostic imaging modality employing the positron emission tomography (PET) tracer [68Ga]Ga-PentixaFor. This tracer has high focal uptake in APAs, whereas low uptake was shown in patients with normal adrenals. Thus, [68Ga]Ga-PentixaFor PET/CT is an imaging modality with the potential to improve subtyping of PA. It is readily available, safe and, as an out-patient procedure, much cheaper diagnostic method than AVS. METHODS AND ANALYSIS: We present a two-step randomised controlled trial (RCT) protocol in which we assess the accuracy of [68Ga]Ga-PentixaFor PET/CT in the first step and compare [68Ga]Ga-PentixaFor PET/CT to AVS in the second step. In the first step, the concordance will be determined between [68Ga]Ga-PentixaFor PET/CT and AVS and a concordance probability is calculated with a Bayesian prediction model. In the second step, we will compare [68Ga]Ga-PentixaFor PET/CT and AVS for clinical outcome and intensity of hypertensive drug use defined as daily defined doses in a RCT. ETHICS AND DISSEMINATION: Ethics approval was acquired from the medical ethical committee East-Netherlands (METC Oost-Nederland). Results will be disseminated through peer-reviewed articles. TRIAL REGISTRATION NUMBER: NL9625.

Intraprocedural MRI-based dosimetry during transarterial radioembolization of liver tumours with holmium-166 microspheres (EMERITUS-1): a phase I trial towards adaptive, image-controlled treatment delivery.

PURPOSE: Transarterial radioembolization (TARE) is a treatment for liver tumours based on injection of radioactive microspheres in the hepatic arterial system. It is crucial to achieve a maximum tumour dose for an optimal treatment response, while minimizing healthy liver dose to prevent toxicity. There is, however, no intraprocedural feedback on the dose distribution, as nuclear imaging can only be performed after treatment. As holmium-166 (166Ho) microspheres can be quantified with MRI, we investigate the feasibility and safety of performing 166Ho TARE within an MRI scanner and explore the potential of intraprocedural MRI-based dosimetry. METHODS: Six patients were treated with 166Ho TARE in a hybrid operating room. Per injection position, a microcatheter was placed under angiography guidance, after which patients were transported to an adjacent 3-T MRI system. After MRI confirmation of unchanged catheter location, 166Ho microspheres were injected in four fractions, consisting of 10%, 30%, 30% and 30% of the planned activity, alternated with holmium-sensitive MRI acquisition to assess the microsphere distribution. After the procedures, MRI-based dose maps were calculated from each intraprocedural image series using a dedicated dosimetry software package for 166Ho TARE. RESULTS: Administration of 166Ho microspheres within the MRI scanner was feasible in 9/11 (82%) injection positions. Intraprocedural holmium-sensitive MRI allowed for tumour dosimetry in 18/19 (95%) of treated tumours. Two CTCAE grade 3-4 toxicities were observed, and no adverse events were attributed to treatment in the MRI. Towards the last fraction, 4/18 tumours exhibited signs of saturation, while in 14/18 tumours, the microsphere uptake patterns did not deviate from the linear trend. CONCLUSION: This study demonstrated feasibility and preliminary safety of a first in-human application of TARE within a clinical MRI system. Intraprocedural MRI-based dosimetry enabled dynamic insight in the microsphere distribution during TARE. This proof of concept yields unique possibilities to better understand microsphere distribution in vivo and to potentially optimize treatment efficacy through treatment personalization. REGISTRATION: Clinicaltrials.gov, identifier NCT04269499, registered on February 13, 2020 (retrospectively registered).

Study Protocol: Adjuvant Holmium-166 Radioembolization After Radiofrequency Ablation in Early-Stage Hepatocellular Carcinoma Patients-A Dose-Finding Study (HORA EST HCC Trial).

PURPOSE: To investigate the biodistribution of holmium-166 microspheres (166Ho-MS) when administered after radiofrequency ablation (RFA) of early-stage hepatocellular carcinoma (HCC). The aim is to establish a perfused liver administration dose that results in a tumoricidal dose of holmium-166 on the hyperaemic zone around the ablation necrosis (i.e. target volume). MATERIALS AND METHODS: This is a multicentre, prospective, dose-escalation study in HCC patients with a solitary lesion 2-5 cm, or a maximum of 3 lesions of ≤ 3 cm each. The day after RFA patients undergo angiography and cone-beam CT (CBCT) with (super)selective infusion of technetium-99 m labelled microalbumin aggregates (99mTc-MAA). The perfused liver volume is segmented from the CBCT and 166Ho-MS is administered to this treatment volume 5-10 days later. The dose of holmium-166 is escalated in a maximum of 3 patient cohorts (60 Gy, 90 Gy and 120 Gy) until the endpoint is reached. SPECT/CT is used to determine the biodistribution of holmium-166. The endpoint is met when a dose of ≥ 120 Gy has been reached on the target volume in 9/10 patients of a cohort. Secondary endpoints include toxicity, local recurrence, disease-free and overall survival. DISCUSSION: This study aims to find the optimal administration dose of adjuvant radioembolization with 166Ho-MS after RFA. Ultimately, the goal is to bring the efficacy of thermal ablation up to par with surgical resection for early-stage HCC patients. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03437382.

Algorithm-based care versus usual care for the early recognition and management of complications after pancreatic resection in the Netherlands: an open-label, nationwide, stepped-wedge cluster-randomised trial.

BACKGROUND: Early recognition and management of postoperative complications, before they become clinically relevant, can improve postoperative outcomes for patients, especially for high-risk procedures such as pancreatic resection. METHODS: We did an open-label, nationwide, stepped-wedge cluster-randomised trial that included all patients having pancreatic resection during a 22-month period in the Netherlands. In this trial design, all 17 centres that did pancreatic surgery were randomly allocated for the timing of the crossover from usual care (the control group) to treatment given in accordance with a multimodal, multidisciplinary algorithm for the early recognition and minimally invasive management of postoperative complications (the intervention group). Randomisation was done by an independent statistician using a computer-generated scheme, stratified to ensure that low-medium-volume centres alternated with high-volume centres. Patients and investigators were not masked to treatment. A smartphone app was designed that incorporated the algorithm and included the daily evaluation of clinical and biochemical markers. The algorithm determined when to do abdominal CT, radiological drainage, start antibiotic treatment, and remove abdominal drains. After crossover, clinicians were trained in how to use the algorithm during a 4-week wash-in period; analyses comparing outcomes between the control group and the intervention group included all patients other than those having pancreatic resection during this wash-in period. The primary outcome was a composite of bleeding that required invasive intervention, organ failure, and 90-day mortality, and was assessed by a masked adjudication committee. This trial was registered in the Netherlands Trial Register, NL6671. FINDINGS: From Jan 8, 2018, to Nov 9, 2019, all 1805 patients who had pancreatic resection in the Netherlands were eligible for and included in this study. 57 patients who underwent resection during the wash-in phase were excluded from the primary analysis. 1748 patients (885 receiving usual care and 863 receiving algorithm-centred care) were included. The primary outcome occurred in fewer patients in the algorithm-centred care group than in the usual care group (73 [8%] of 863 patients vs 124 [14%] of 885 patients; adjusted risk ratio [RR] 0·48, 95% CI 0·38-0·61; p<0·0001). Among patients treated according to the algorithm, compared with patients who received usual care there was a decrease in bleeding that required intervention (47 [5%] patients vs 51 [6%] patients; RR 0·65, 0·42-0·99; p=0·046), organ failure (39 [5%] patients vs 92 [10%] patients; 0·35, 0·20-0·60; p=0·0001), and 90-day mortality (23 [3%] patients vs 44 [5%] patients; 0·42, 0·19-0·92; p=0·029). INTERPRETATION: The algorithm for the early recognition and minimally invasive management of complications after pancreatic resection considerably improved clinical outcomes compared with usual care. This difference included an approximate 50% reduction in mortality at 90 days. FUNDING: The Dutch Cancer Society and UMC Utrecht.

Development of an MRI-Guided Approach to Selective Internal Radiation Therapy Using Holmium-166 Microspheres.

Selective internal radiation therapy (SIRT) is a treatment modality for liver tumours during which radioactive microspheres are injected into the hepatic arterial tree. Holmium-166 (166Ho) microspheres used for SIRT can be visualized and quantified with MRI, potentially allowing for MRI guidance during SIRT. The purpose of this study was to investigate the MRI compatibility of two angiography catheters and a microcatheter typically used for SIRT, and to explore the detectability of 166Ho microspheres in a flow phantom using near real-time MRI. MR safety tests were performed at a 3 T MRI system according to American Society for Testing of Materials standard test methods. To assess the near real-time detectability of 166Ho microspheres, a flow phantom was placed in the MRI bore and perfused using a peristaltic pump, simulating the flow in the hepatic artery. Dynamic MR imaging was performed using a 2D FLASH sequence during injection of different concentrations of 166Ho microspheres. In the safety assessment, no significant heating (ΔTmax 0.7 °C) was found in any catheter, and no magnetic interaction was found in two out of three of the used catheters. Near real-time MRI visualization of 166Ho microsphere administration was feasible and depended on holmium concentration and vascular flow speed. Finally, we demonstrate preliminary imaging examples on the in vivo catheter visibility and near real-time imaging during 166Ho microsphere administration in an initial patient case treated with SIRT in a clinical 3 T MRI. These results support additional research to establish the feasibility and safety of this procedure in vivo and enable the further development of a personalized MRI-guided approach to SIRT.

Resectability and Ablatability Criteria for the Treatment of Liver Only Colorectal Metastases: Multidisciplinary Consensus Document from the COLLISION Trial Group.

The guidelines for metastatic colorectal cancer crudely state that the best local treatment should be selected from a 'toolbox' of techniques according to patient- and treatment-related factors. We created an interdisciplinary, consensus-based algorithm with specific resectability and ablatability criteria for the treatment of colorectal liver metastases (CRLM). To pursue consensus, members of the multidisciplinary COLLISION and COLDFIRE trial expert panel employed the RAND appropriateness method (RAM). Statements regarding patient, disease, tumor and treatment characteristics were categorized as appropriate, equipoise or inappropriate. Patients with ECOG≤2, ASA≤3 and Charlson comorbidity index ≤8 should be considered fit for curative-intent local therapy. When easily resectable and/or ablatable (stage IVa), (neo)adjuvant systemic therapy is not indicated. When requiring major hepatectomy (stage IVb), neo-adjuvant systemic therapy is appropriate for early metachronous disease and to reduce procedural risk. To downstage patients (stage IVc), downsizing induction systemic therapy and/or future remnant augmentation is advised. Disease can only be deemed permanently unsuitable for local therapy if downstaging failed (stage IVd). Liver resection remains the gold standard. Thermal ablation is reserved for unresectable CRLM, deep-seated resectable CRLM and can be considered when patients are in poor health. Irreversible electroporation and stereotactic body radiotherapy can be considered for unresectable perihilar and perivascular CRLM 0-5cm. This consensus document provides per-patient and per-tumor resectability and ablatability criteria for the treatment of CRLM. These criteria are intended to aid tumor board discussions, improve consistency when designing prospective trials and advance intersociety communications. Areas where consensus is lacking warrant future comparative studies.

Care after pancreatic resection according to an algorithm for early detection and minimally invasive management of pancreatic fistula versus current practice (PORSCH-trial): design and rationale of a nationwide stepped-wedge cluster-randomized trial.

BACKGROUND: Pancreatic resection is a major abdominal operation with 50% risk of postoperative complications. A common complication is pancreatic fistula, which may have severe clinical consequences such as postoperative bleeding, organ failure and death. The objective of this study is to investigate whether implementation of an algorithm for early detection and minimally invasive management of pancreatic fistula may improve outcomes after pancreatic resection. METHODS: This is a nationwide stepped-wedge, cluster-randomized, superiority trial, designed in adherence to the Consolidated Standards of Reporting Trials (CONSORT) guidelines. During a period of 22 months, all Dutch centers performing pancreatic surgery will cross over in a randomized order from current practice to best practice according to the algorithm. This evidence-based and consensus-based algorithm will provide daily multilevel advice on the management of patients after pancreatic resection (i.e. indication for abdominal imaging, antibiotic treatment, percutaneous drainage and removal of abdominal drains). The algorithm is designed to aid early detection and minimally invasive step-up management of postoperative pancreatic fistula. Outcomes of current practice will be compared with outcomes after implementation of the algorithm. The primary outcome is a composite of major complications (i.e. post-pancreatectomy bleeding, new-onset organ failure and death) and will be measured in a sample size of at least 1600 patients undergoing pancreatic resection. Secondary endpoints include the individual components of the primary endpoint and other clinical outcomes, healthcare resource utilization and costs analysis. Follow up will be up to 90 days after pancreatic resection. DISCUSSION: It is hypothesized that a structured nationwide implementation of a dedicated algorithm for early detection and minimally invasive step-up management of postoperative pancreatic fistula will reduce the risk of major complications and death after pancreatic resection, as compared to current practice. TRIAL REGISTRATION: Netherlands Trial Register: NL 6671. Registered on 16 December 2017.

The various therapeutic applications of the medical isotope holmium-166: a narrative review.

Over the years, a broad spectrum of applications of the radionuclide holmium-166 as a medical isotope has been established. The isotope holmium-166 is attractive as it emits high-energy beta radiation which can be used for a therapeutic effect and gamma radiation which can be used for nuclear imaging purposes. Furthermore, holmium-165 can be visualized by MRI because of its paramagnetic properties and by CT because of its high density. Since holmium-165 has a natural abundance of 100%, the only by-product is metastable holmium-166 and no costly chemical purification steps are necessary for production of nuclear reactor derived holmium-166. Several compounds labelled with holmium-166 are now used in patients, such Ho166-labelled microspheres for liver malignancies, Ho166-labelled chitosan for hepatocellular carcinoma (HCC) and [166Ho]Ho DOTMP for bone metastases. The outcomes in patients are very promising, making this isotope more and more interesting for applications in interventional oncology. Both drugs as well as medical devices labelled with radioactive holmium are used for internal radiotherapy. One of the treatment possibilities is direct intratumoural treatment, in which the radioactive compound is injected with a needle directly into the tumour. Numerous other applications have been developed, like patches for treatment of skin cancer and holmium labelled antibodies and peptides. The second major application that is currently clinically applied is selective internal radiation therapy (SIRT, also called radioembolization), a novel treatment option for liver malignancies. This review discusses medical drugs and medical devices based on the therapeutic radionuclide holmium-166.

Adrenal vein sampling versus CT scan to determine treatment in primary aldosteronism: an outcome-based randomised diagnostic trial.

BACKGROUND: The distinction between unilateral aldosterone-producing adenoma or bilateral adrenal hyperplasia as causes of primary aldosteronism is usually made by adrenal CT or by adrenal vein sampling (AVS). Whether CT or AVS represents the best test for diagnosis remains unknown. We aimed to compare the outcome of CT-based management with AVS-based management for patients with primary aldosteronism. METHODS: In a randomised controlled trial, we randomly assigned patients with aldosteronism to undergo either adrenal CT or AVS to determine the presence of aldosterone-producing adenoma (with subsequent treatment consisting of adrenalectomy) or bilateral adrenal hyperplasia (subsequent treatment with mineralocorticoid receptor antagonists). The primary endpoint was the intensity of drug treatment for obtaining target blood pressure after 1 year of follow-up, in the intention-to-diagnose population. Intensity of drug treatment was expressed as daily defined doses. Key secondary endpoints included biochemical outcome in patients who received adrenalectomy, health-related quality of life, cost-effectiveness, and adverse events. This trial is registered with ClinicalTrials.gov, number NCT01096654. FINDINGS: We recruited 200 patients between July 6, 2010, and May 30, 2013. Of the 184 patients that completed follow-up, 92 received CT-based treatment (46 adrenalectomy and 46 mineralocorticoid receptor antagonist) and 92 received AVS-based treatment (46 adrenalectomy and 46 mineralocorticoid receptor antagonist). We found no differences in the intensity of antihypertensive medication required to control blood pressure between patients with CT-based treatment and those with AVS-based treatment (median daily defined doses 3·0 [IQR 1·0-5·0] vs 3·0 [1·1-5·9], p=0·52; median number of drugs 2 [IQR 1-3] vs 2 [1-3], p=0·87). Target blood pressure was reached in 39 (42%) patients and 41 (45%) patients, respectively (p=0·82). On secondary endpoints we found no differences in health-related quality of life (median RAND-36 physical scores 52·7 [IQR 43·9-56·8] vs 53·2 [44·0-56·8], p=0·83; RAND-36 mental scores 49·8 [43·1-54·6] vs 52·7 [44·9-55·5], p=0·17) for CT-based and AVS-based treatment. Biochemically, 37 (80%) of patients with CT-based adrenalectomy and 41 (89%) of those with AVS-based adrenalectomy had resolved hyperaldosteronism (p=0·25). A non-significant mean difference of 0·05 (95% CI -0·04 to 0·13) in quality-adjusted life-years (QALYs) was found to the advantage of the AVS group, associated with a significant increase in mean health-care costs of €2285 per patient (95% CI 1323-3248). At a willingness-to-pay value of €30 000 per QALY, the probability that AVS compared with CT constitutes an efficient use of health-care resources in the diagnostic work-up of patients with primary aldosteronism is less than 0·2. There was no difference in adverse events between groups (159 events of which nine were serious vs 187 events of which 12 were serious) for CT-based and AVS-based treatment. INTERPRETATION: Treatment of primary aldosteronism based on CT or AVS did not show significant differences in intensity of antihypertensive medication or clinical benefits for patients after 1 year of follow-up. This finding challenges the current recommendation to perform AVS in all patients with primary aldosteronism. FUNDING: Netherlands Organisation for Health Research and Development-Medical Sciences, Institute of Cardiology, Warsaw.

Image Registration of Cone-Beam Computer Tomography and Preprocedural Computer Tomography Aids in Localization of Adrenal Veins and Decreasing Radiation Dose in Adrenal Vein Sampling.

PURPOSE: We assessed whether image registration of cone-beam computed tomography (CT) (CBCT) and contrast-enhanced CT (CE-CT) images indicating the locations of the adrenal veins can aid in increasing the success rate of first-attempts adrenal vein sampling (AVS) and therefore decreasing patient radiation dose. MATERIALS AND METHODS: CBCT scans were acquired in the interventional suite (Philips Allura Xper FD20) and rigidly registered to the vertebra in previously acquired CE-CT. Adrenal vein locations were marked on the CT image and superimposed with live fluoroscopy and digital-subtraction angiography (DSA) to guide the AVS. Seventeen first attempts at AVS were performed with image registration and retrospectively compared with 15 first attempts without image registration performed earlier by the same 2 interventional radiologists. First-attempt AVS was considered successful when both adrenal vein samples showed representative cortisol levels. Sampling time, dose-area product (DAP), number of DSA runs, fluoroscopy time, and skin dose were recorded. RESULTS: Without image registration, the first attempt at sampling was successful in 8 of 15 procedures indicating a success rate of 53.3%. This increased to 76.5% (13 of 17) by adding CBCT and CE-CT image registration to AVS procedures (p = 0.266). DAP values (p = 0.001) and DSA runs (p = 0.026) decreased significantly by adding image registration guidance. Sampling and fluoroscopy times and skin dose showed no significant changes. CONCLUSION: Guidance based on registration of CBCT and previously acquired diagnostic CE-CT can aid in enhancing localization of the adrenal veins thereby increasing the success rate of first-attempt AVS with a significant decrease in the number of used DSA runs and, consequently, radiation dose required.

Endovascular treatment of internal iliac artery stenosis in patients with buttock claudication.

AIM: To assess the technical feasibility and clinical outcome of percutaneous transluminal angioplasty (PTA) with and without stent placement for treatment of buttock claudication caused by internal iliac artery (IIA) stenosis. METHODS: Between September 2001 and July 2011, thirty-four patients with buttock claudication underwent endovascular treatment. After angiographic lesion evaluation PTA with or without stent placement was performed. Technical success was recorded. Clinical outcome post-treatment was assessed at three months post-intervention and was classified as: 1) complete relief of symptoms, 2) partial relief, or 3) no relief of symptoms. Complications during follow-up were recorded. RESULTS: Forty-four lesions in 34 symptomatic patients were treated with PTA. Eight lesions were treated with additional stent placement. Technical success was achieved in 40/44 lesions (91%). Three procedure-related minor complications occurred, i.e. asymptomatic conservatively treated intimal dissections. After a median of 2.9 months, patients experienced no relief of symptoms in 7/34 cases (21%), partial relief in 14/34 cases (41%), and complete relief in 13/34 cases (38%). Six patients required a reintervention during follow-up. CONCLUSION: Endovascular treatment of IIA stenosis has a high technical success rate and a low complication rate. Complete or partial relief of symptoms is achieved in the majority (79%) of patients.

Assessment of needle guidance devices for their potential to reduce fluoroscopy time and operator hand dose during C-arm cone-beam computed tomography-guided needle interventions.

PURPOSE: To assess whether the use of needle guidance devices can reduce fluoroscopy time and operator hand dose during cone-beam computed tomography-guided needle interventions. MATERIALS AND METHODS: The freehand technique was compared with techniques employing two distinct needle holders and a ceiling-mounted laser guidance technique. Laser guidance was used either alone or in combination with needle holders. Four interventional radiologists were instructed to reach predetermined targets in an abdominal phantom using these techniques. Each operator used all six techniques three times. Fluoroscopy time, procedure time, operator hand dose, and needle tip deviation were obtained for all simulated needle interventions. All data are presented as median (ranges). RESULTS: All procedures were successfully completed within 2-4 minutes, resulting in a deviation from target of 0.8 mm (0-4.7). In freehand procedures, the fluoroscopy time to reach the target was 50 seconds (31-98 s). Laser guidance, used alone or in combination with needle holders, reduced fluoroscopy time to 31 seconds (14-68 s) (P<.02). The operator hand dose in freehand procedures was 275 µSv (20-603 µSv). Laser guidance alone or in combination with needle holders resulted in a reduction of the hand dose to<36 µSv (5-82 µSv) per procedure (P<.001). There were no statistically significant effects on hand dose levels or fluoroscopy time when the needle holders were employed alone. CONCLUSIONS: Compared with the freehand technique, all three tested needle guidance devices performed with equivalent efficiency in terms of accuracy and procedure time. Only the addition of laser guidance was found to reduce both fluoroscopy time and operator hand dose.

Single versus duplicate blood samples in ACTH stimulated adrenal vein sampling.

BACKGROUND: Adrenal vein sampling (AVS) is the preferred test for subtyping primary aldosteronism. However, the procedure is technically demanding and costly. In AVS it is common practice to take duplicate blood samples at each location. In this paper we explore whether a single sample procedure leads to a different conclusion concerning the location of adrenal aldosterone secretion than a duplicate sample procedure. METHODS: AVS procedures with duplicate measurements performed in our university medical center between 2005 and 2010 were evaluated retrospectively. We compared the conclusions regarding selectivity and lateralization based on the first sample taken (A) to the conclusions based on the average of duplicate samples (AB). We also calculated the number needed to be sampled in duplicate to prevent one misclassification. RESULTS: Ninety-six AVS procedures of 82 patients were included. The concordance in AVS conclusions between samples A and AB was 98-100%, depending on the criteria used for selectivity and lateralization. With permissive and strict criteria the number needed to be sampled in duplicate were infinite and 48, respectively. CONCLUSIONS: The incremental benefit of duplicate sampling compared to single sampling is low. Therefore, in the case of technical difficulties during AVS, conclusions can also be reliably drawn from a single blood sample.

Uterine fibroid embolisation for symptomatic uterine fibroids: a survey of clinical practice in Europe.

PURPOSE: To assess current uterine fibroid embolisation (UFE) practice in European countries and determine the clinical environment for UFE in different hospitals. MATERIAL AND METHODS: In May 2009, an invitation for an online survey was sent by e-mail to all members of the Cardiovascular and Interventional Radiologic Society of Europe, representing a total number of 1,250 different candidate European treatment centres. The survey covered 21 questions concerning local UFE practice. RESULTS: A total of 282 respondents completed the questionnaire. Fifteen questionnaires were excluded because they were doubles from centres that had already returned a questionnaire. The response rate was 267 of 1,250 centres (21.4%). Ninety-four respondents (33%) did not perform UFE and were excluded, and six centres were excluded because demographic data were missing. The remaining 167 respondents from different UFE centres were included in the study. Twenty-six percent of the respondents were from the United Kingdom (n = 43); 16% were from Germany (n = 27); 11% were from France (n = 18); and the remaining 47% (n = 79) were from other European countries. Most centres (48%, n = 80) had 5 to 10 years experience with UFE and performed 10 to 50 procedures annually (53% [n = 88]) of respondents). Additional demographic data, as well as specific data on referral of patients, UFE techniques used, and periprocedural and postprocedural, care will be provided. CONCLUSION: Although UFE as an alternative treatment for hysterectomy or myomectomy is widespread in Europe, its impact on the management of the patient with symptomatic fibroids seems, according to the overall numbers of UFE procedures, somewhat disappointing. Multiple factors might be responsible for this observation.