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At least 685 records · Page 38

Ultrasound-guided percutaneous catheter drainage of various types of ruptured amebic liver abscess: a report of 117 cases from a highly endemic zone of India

Objective: To determine the efficacy and safety ultrasound-guided percutaneous catheter drainage (US-PCD) in management of various types of ruptured amebic liver abscess including free rupture (FR) with diffuse intraperitoneal fluid collections (DIFC). Methods: This study analyzed 117 patients with ruptured ALA who underwent US-PCD. The indication for US-PCD was failure to respond to conservative treatment and/or percutaneous needle aspiration. Results: Majority of patients were locally fermented alcohol abusers (95%), and malnourished (75%). Ninety-eight patients had intraperitoneal rupture including 66 contained rupture (CR) with localized intraperitoneal fluid collection (LIFC) and 32 FR with DIFC. Pleuropulmonary complication was found in 19 patients including 13 pleural and 6 pulmonary. A total of 333 catheters were used to drain 202 abscess cavities and associated fluid collections. US-PCD was technically and clinically successful in all cases. Multiple sessions (median 2; range 2–5) of PCD required with upsizing the catheter (median 14 F; range 14–20 F) and placement of additional catheter in 26 (22%) patients. The patients with FR with DIFC required more number of catheters (p = 0.01) and had longer hospital stay (p = 0.01). No major procedure related complication was observed. Six patients developed secondary bacterial infection; two of them presented with cavito-cutaneous fistula at catheter insertion site, and one with cholangitis due to biliary stricture formation necessitating subsequent endoscopic treatment. Post-procedural death occurred from sepsis in a patient with FR. Conclusion: US-PCD is a safe and effective mode of treatment for ruptured ALA including FR with DIFCs. We recommend PCD as a first-line therapy for ruptured ALA.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Improving preoperative detection of synchronous liver metastases in pancreatic cancer with combined contrast-enhanced and diffusion-weighted MRI

Purpose: To explore the value of gadolinium-enhanced MRI combined with diffusion-weighted MRI (Gd-enhanced MRI with DWI) in addition to contrast-enhanced CT (CECT) for detection of synchronous liver metastases for potentially resectable pancreatic cancer. Methods: By means of a retrospective cohort study we included patients with potentially resectable pancreatic cancer on CECT, who underwent Gd-enhanced MRI with DWI between January 2012 and December 2016. A single observer evaluated MRI and CT and was blinded to imaging, pathology, and surgery reports. Liver lesions were scored in both modalities, using a 3-point scale: 1-benign, 2-indeterminate, 3- malignant (i.e., metastasis). The primary outcome parameters were the presence of liver metastases on Gd-enhanced MRI with DWI and the sensitivity of Gd-enhanced MRI with DWI for synchronous liver metastases. Results: We included 66 patients (42 men, 24 women; median age 65 years, range 36–82 years). In 19 patients, liver metastases were present, which were confirmed by histopathology (n = 12), {sup 18}FDG-PET (n = 6), or surgical inspection (n = 1). Gd-enhanced MRI with DWI showed metastases in 16/19 patients (24%), which resulted in a sensitivity of 84% (95% CI 60–97%). Contrast-enhanced MRI showed 156 and DWI 397 metastases (p = 0.051), and 339 were particularly small (< 5 mm). Conclusions: In this study, Gd-enhanced MRI with DWI detected synchronous liver metastases in 24% of patients with potentially resectable pancreatic cancer on CECT with a sensitivity of 84%. Diffusion-weighted MRI showed a greater number of metastases than any other sequence, particularly small metastases (< 5 mm).

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Morphological predictors for lymph node metastases on computed tomography in colon cancer

Introduction/Background: The aim of the study was to assess morphological predictors for lymph node metastases (Stage III disease) in colon cancer on computed tomography. Methods and materials: Ninety-four patients with histology-proven colon cancer (adenocarcinoma) who underwent elective primary curative resection between the years 2012 and 2014 were included. Contrast-enhanced CT examinations were independently reviewed by two blinded observers regarding tumor location, depth of tumor invasion, and presence of lymph node metastases. Ocular presence of internal heterogeneity and presence of irregular outer border were used as morphological criteria for lymph node involvement. Protocol-based histopathology after curative surgery served as reference standard. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and accuracy for each morphological criterion for prediction of stage III disease were calculated. Inter-observer agreement was compared using Kappa statistics. Results: According to histopathology, 59 patients were staged as I–II disease and 35 patients were staged as stage III disease. The presence of internal heterogeneity in a lymph node on CT resulted in moderate sensitivity (66–77%) but high specificity (95–95%) for prediction of Stage III disease by both observers. The presence of irregular outer border also resulted in poor sensitivity (49–54%) but high specificity (97–97%). The combination of either internal heterogeneity and/or irregular outer border per patient resulted in a moderate sensitivity (67–77%) and high specificity (95–95%), PPV (89–96%), and NPV (84–88%). Inter-observer agreement (Cohens Kappa) was 0.72. Consensus reading for the combined criteria resulted in sensitivity and specificity of 69% and 100%, respectively. Conclusion: Using morphological criteria for lymph node metastases on CT examination in patients with colon cancer results in high specificity but moderate sensitivity in predicting stage III disease.

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Liver Hypertrophy After Percutaneous Portal Vein Embolization: Comparison of N-Butyl-2-Cyanocrylate Versus Sodium Acrylate-Vinyl Alcohol Copolymer Particles in a Swine Model

Purpose: Percutaneous portal vein embolization (PPVE) induces hypertrophy of the future liver remnant before hepatic resection. The ideal embolic material has not yet been determined. We compared N-butyl-2-cyanocrylate (NBCA) with sodium acrylate-vinyl alcohol copolymer particles using a swine model. Materials and Methods: Twelve pigs underwent PPVE. Six pigs (group A) were embolized with NBCA, and 6 pigs (group B) were embolized with sodium acrylate-vinyl alcohol copolymer particles. Computed tomographic volumetry of the embolized lobe (EL) and the nonembolized lobe (NEL), along with liver function tests, was performed before and at 14 and 28 days after embolization. Tissue samples from both lobes were taken 14 and 28 days after PPVE. Results: NEL-volume and NEL-ratio increases were significantly higher in group A at 14 and 28 days after PPVE (78 and 52% and 91 and 66%, respectively) than in group B (32 and 12% and 28 and 10%, respectively) (p < 0.05). Percent change of the EL-volume was significantly higher for group A at 28 days after PPVE. No statistically significant difference was found between the groups regarding hepatocyte proliferation on the NEL and apoptosis on the EL at both time intervals. Conclusion: PPVE using NBCA is more efficient and causes more NEL hypertrophy than microspheres.

60 APPLIED LIFE SCIENCES↗

External Carotid-Internal Jugular Fistula as a Late Complication After Carotid Endarterectomy: A Rare Case

A 66-year-old man presented with mild amnesia, progressive fatigue, ataxia, visual hallucinations, and debility. His past medical history included right-sided carotid endarterectomy performed elsewhere 6 years previously. Cranial magnetic resonance imaging showed left parieto-occipital arteriovenous malformation-like tortous vessels, venous congestion, and ischemic areas. Cerebral angiography showed right-sided compound external carotid artery-internal jugular vein (IJV) fistula, and distal occlusion of the right IJV. Transvenous embolization via contralateral IJV was performed, and the fistula, together with fistulous portion of the distal IJV, was sealed using coils. Two years later, patient is well with normal neurologic examination findings. The presence of an arteriovenous communication after vascular surgery is a serious complication with potential long-term effects and therefore should be diagnosed and treated as promptly as possible.

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Detection of Type II Endoleak After Endovascular Aortic Repair: Comparison Between Magnetic Resonance Angiography and Blood-Pool Contrast Agent and Dual-Phase Computed Tomography Angiography

PurposeThis prospective study was designed to assess the diagnostic value of magnetic resonance angiography (MRA) with blood-pool contrast agent (gadofosveset) in the detection of type-II endoleak after endovascular aortic repair (EVAR).MethodsThirty-two patients with aortic aneurysms who had undergone EVAR were included in this study. All patients were examined by dual-phase computed tomography angiography (CTA) as well as MRA with gadofosveset in the first-pass and steady-state phases. Two independent readers evaluated the images of CTA and MRA in terms of endoleak type II, feeding vessel, and image quality.ResultsMedian follow-up-time after EVAR was 22 months (range 4 to 59). Endoleak type II was detected by CTA in 12 of 32 patients (37.5%); MRA detected endoleak in all of these patients as well as in another 9 patients (n = 21, 65.6%), of whom the endoleaks in 6 patients showed an increasing diameter. Most endoleaks were detected in the steady-state phase (n = 14). The decrease in diameter of the aneurysmal sac was significantly greater in the patients without a visible endoleak that was visible on MRA (P = 0.004). In the overall estimation of diagnostic accuracy, MRA was judged superior to CTA in 66% of all examinations.ConclusionMRA with gadofosveset appeared superior to CTA, and has higher diagnostic accuracy, in the detection of endoleak after EVAR.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Initial Results of Catheter-Directed Ultrasound-Accelerated Thrombolysis for Thromboembolic Obstructions of the Aortofemoral Arteries: A Feasibility Study

Purpose: This article reports the 30-day technical and clinical outcome of ultrasound (US)-accelerated thrombolysis in patients with aortofemoral arterial thromboembolic obstructions. Methods: A prospective cohort study was conducted from December 2008 to December 2009 of patients who were treated with US-accelerated thrombolysis for thromboembolic obstructions of aortofemoral arteries or bypasses. Urokinase was infused in a dosage of 100,000 IU per hour. Twice daily, a control angiography was performed. Thirty-day follow-up consisted of duplex scanning, combined with magnetic resonance angiography. Results: The study included 21 consecutive patients (20 men; median age, 66 (range, 52-80) years) with 24% artery versus 76% bypass occlusions. Median duration of symptoms was 11 (range, 7-140) days. Median occlusion length was 32 (range, 6-80) cm. In 20 patients (95%), an US-accelerated thrombolysis catheter could be successfully placed. In one patient, placement of an US-accelerated thrombolysis catheter was technically not feasible, and therefore a standard catheter was placed. Median thrombolysis time was 26.5 (range, 8.5-72) hours. Complete thrombolysis (>95% lysis of thrombus) was achieved in 20 patients; in 9 patients within 24 hours. Median ankle-brachial index (ABI) increased from 0.28 (range, 0-0.85) to 0.91 (range, 0.58-1.35). One patient had a thromboembolic complication and needed surgical intervention. No hemorrhagic complications, and no deaths occurred. At 30-day follow-up, 17 of 21 patients (81%) had a patent artery or bypass. Conclusions: This feasibility study showed a high technical success rate of US-accelerated thrombolysis for aortofemoral arterial obstructions. US-accelerated thrombolysis led to complete lysis within 24 hours in almost half of patients, with a low 30-day major complication rate.

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Percutaneous Treatment of Peripheral Vascular Malformations in Children: Long-Term Clinical Outcome

Purpose: This study was designed to assess the rate of complications and clinical failure at 3 and 12 months after percutaneous treatment of vascular malformations in children. Furthermore, we describe patient satisfaction of treatment results during 5 years of follow-up. Methods: In a retrospective cohort study, we evaluated 26 patients younger than aged 19 years who were treated for symptomatic vascular malformations. Data on treatment outcomes and patient satisfactions were obtained with a precoded structured questionnaire. Patient files and imaging data were retrieved to obtain information regarding the vascular malformations and treatment. Clinical success was defined as disappearance or partial improvement of the complaints. Patient satisfaction was declared whenever patients answered in the questionnaire that they were satisfied with the treatment results. Results: Of 26 eligible patients, we included 23 (88%). The mean follow-up was 36 (range, 15-127) months. Posttreatment, 87% (20/23; 95% confidence interval (CI), 66-97%) of patients reported clinical success at 3 months. At 1, 2, 3, 4, and 5 years of follow-up this percentage was 74%, 59%, 59%, 59%, and 59%, respectively. Eleven (48%, 95% CI 27-69%) patients had experienced complications and 22% (95% CI 7-44%) had major complications, of which 5 had required additional treatment. In all, 83% (19/23) of the patients reported satisfaction with the treatment. Conclusions: Percutaneous treatment of vascular malformations improved clinical symptoms in 87% of the patients at 3 months and were sustainable for half of all patients during a 5-year follow-up period. However, major complications were seen in 22%.

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Single-Session Radiofrequency Ablation of Bilateral Lung Metastases

Purpose: This retrospective study examined the feasibility and efficacy of bilateral lung radiofrequency ablation (RFA) performed in a single session. Methods: From 2002-2009, patients with bilateral lung metastases were treated by RFA, where possible in a single session under general anesthesia with CT guidance. The second lung was punctured only if no complications occurred after treatment of the first lung. Five lung metastases maximum per patient were treated by RFA and prospectively followed. The primary endpoint was the evaluation of acute and delayed complications. Secondary endpoints were calculation of hospitalization duration, local efficacy, median survival, and median time to tumor progression. Local efficacy was evaluated on CT or positron emission tomography (PET) CT. Results: Sixty-seven patients were treated for bilateral lung metastases with RFA (mean age, 62 years). Single-session treatment was not possible in 40 due to severe pneumothoraces (n = 24), bilateral pleural contact (n = 14), and operational exclusions (n = 2). Twenty-seven (41%) received single-session RFA of lesions in both lungs for 66 metastases overall. Fourteen unilateral and four bilateral pneumothoraces occurred (18 overall, 66.7%). Unilateral (n = 13) and bilateral (n = 2) chest tube drainage was required. Median hospitalization was 3 (range, 2-8) days. Median survival was 26 months (95% confidence interval (CI), 19-33). Four recurrences on RFA sites were observed (4 patients). Median time to tumor progression was 9.5 months (95% CI, 4.2-23.5). Conclusions: Although performing single-session bilateral lung RFA is not always possible due to pneumothoraces after RFA of first lung, when it is performed, this technique is safe and effective.

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Long-Term Follow-up of Uterine Artery Embolization for Symptomatic Adenomyosis

Introduction: Long-term results of uterine artery embolization (UAE) for adenomyosis are largely unknown. We assess long-term outcome of UAE in 40 women with adenomyosis. Materials and methods: Between March 1999 and October 2006, 40 consecutive women with adenomyosis (22 in combination with fibroids) were treated with UAE. Changes in junction zone thickness were assessed with magnetic resonance imaging (MRI) at baseline and again at 3 months. After a mean clinical follow-up of 65 months (median 58 [range 38-129]), women filled out the uterine fibroid symptom and quality of life (UFS-QoL) questionnaire, which had additional questions on the long-term evolution of baseline symptoms and adverse events. Results: During follow-up, 7 of 40 women (18%) underwent hysterectomy. Among these 7 women, the junction zones were significantly thicker, both at baseline (mean 23 vs. 16 mm, P = 0.028) and at 3-month follow-up (mean 15 vs. 9 mm, P = 0.034). Of 33 women with preserved uterus, 29 were asymptomatic. Four patients had symptom severity scores of 50 to 85 and overall QoL scores of 60 to 66, indicating substantial clinical symptoms. There was no relation between clinical outcome and the initial presence of fibroids in addition to adenomyosis. Conclusion: In women with therapy-resistant adenomyosis, UAE resulted in long-term preservation of the uterus in the majority. Most patients with preserved uterus were asymptomatic. The only predictor for hysterectomy during follow-up was initial thickness of the junction zone. The presence or absence of fibroids in addition to adenomyosis had no relation with the need for hysterectomy or clinical outcome.

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Radiation Exposure in Nonvascular Fluoroscopy-Guided Interventional Procedures

Purpose: To investigate the radiation exposure in non-vascular fluoroscopy guided interventions and to search strategies for dose reduction. Materials and Methods: Dose area product (DAP) of 638 consecutive non-vascular interventional procedures of one year were analyzed with respect to different types of interventions; gastrointestinal tract, biliary interventions, embolizations of tumors and hemorrhage. Data was analyzed with special focus on the fluoroscopy doses and frame doses. The third quartiles (Q3) of fluoroscopy dose values were defined in order to set a reference value for our in-hospital practice. Results: Mean fluoroscopy times of gastrostomy, jejunostomy, right and left sided percutaneous biliary drainage, chemoembolization of the liver and embolization due to various hemorrhages were 5.9, 8.6, 13.5, 16.6, 17.4 and 25.2 min, respectively. The respective Q3 total DAP were 52.9, 73.3, 155.1, 308.4, 428.6 and 529.3 Gy*cm{sup 2}. Overall, around 66% of the total DAP originated from the radiographic frames with only 34% of the total DAP applied by fluoroscopy (P < 0.001). The investigators experience had no significant impact on the total DAP applied, most likely since there was no stratification to intervention-complexity. Conclusion: To establish Diagnostic Reference Levels (DRLs), there is a need to establish a registry of radiation dose data for the most commonly performed procedures. Documentation of interventional procedures by fluoroscopy 'grabbing' has the potential to considerably reduce radiation dose applied and should be used instead of radiographic frames whenever possible.

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Ten Years of Experience with the GORE EXCLUDER{sup Registered-Sign} Stent-Graft for the Treatment of Aortic and Iliac Aneurysms: Outcomes from a Single Center Study

Purpose: This study was designed to assess the long-term outcome of selected patients with aortic, aortoiliac, and isolated common iliac aneurysms treated with the GORE EXCLUDER{sup Registered-Sign} stent-graft. Methods: Between December 1998 and June 2010, 121 nonconsecutive patients underwent insertion of a GORE EXCLUDER{sup Registered-Sign} stent-graft to treat an aortic (n = 80; 66%), aortoiliac (n = 25; 21%), or isolated common iliac (n = 16; 13%) aneurysm. Procedural and follow-up data were collected prospectively. Primary endpoints are overall survival, intervention-free survival, and freedom from aneurysm rupture. Secondary endpoints are device- and procedure-related complications, including all types of endoleaks or endotension, and reintervention. Results: The mean follow-up is 4.98 years (standard deviation, 3.18; median follow-up, 4.05 years). The estimated percentage overall survival (with 95% confidence interval) after respectively 5 and 10 years of follow-up is 74.5% (65.8; 81.3) and 57.8% (47.7; 66.7). The estimated intervention-free survival after respectively 5 and 10 years is 90% (84.3; 96.1) and 77.7% (67; 88.4). There was no aneurysm rupture during follow-up. Early postoperative complications occurred in 16 patients (13%); none were fatal. Late reinterventions were performed in 18 patients (15%). Finally, throughout the follow-up period, endoleaks were identified: type I (n = 4; 3%); type II (n = 39; 32%); type III (n = 0; 0%); endotension was seen in 11 patients (9%). Conclusions: Aneurysm exclusion with use of the GORE EXCLUDER{sup Registered-Sign} stent-graft is durable through a mean follow-up of nearly 5 years. There was no postprocedural aneurysm rupture. Complications occurred throughout the follow-up period, requiring continued clinical and radiological surveillance.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Patency of Femoral Tunneled Hemodialysis Catheters and Factors Predictive of Patency Failure

Purpose: To determine the patency rates of and factors associated with increased risk of patency failure in patients with femoral vein tunneled hemodialysis catheters. Methods: All femoral tunneled catheter insertions from 1996 to 2006 were reviewed, during which time 123 catheters were inserted. Of these, 66 were exchanges. Patients with femoral catheter failure versus those with femoral catheter patency were compared. Confounding factors, such as demographic and procedural factors, were incorporated and assessed using univariate and multivariable Cox proportional hazards regression analyses. Results: Mean catheter primary patency failure time was 96.3 days (SE 17.9 days). Primary patency at 30, 60, 90, and 180 days was 53.8%, 45.4%, 32.1%, and 27.1% respectively. Crude rates of risk of catheter failure did not suggest a benefit for patients receiving catheters introduced from one side versus the other, but more cephalad location of catheter tip was associated with improved patency. Multivariate analysis showed that patients whose catheters were on the left side (p = 0.009), were of increasing age at the time of insertion (p = 0.002) and that those who had diabetes (p = 0.001) were at significantly greater risk of catheter failure. The catheter infection rate was 1.4/1000 catheter days. Conclusion: Patients who were of a more advanced age and had diabetes were at greater risk of femoral catheter failure, whereas those who received femoral catheters from the right side were less at risk of catheter failure.

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Iliac Artery Stent Placement Relieves Claudication in Patients with Iliac and Superficial Femoral Artery Lesions

Purpose. To evaluate the efficacy of iliac artery stent placement for relief of claudication in patients with both iliac and superficial femoral artery (SFA) lesions. Methods. Stent placement for only iliac artery occlusive disease was performed in 94 limbs (74 patients) with both iliac and SFA occlusive disease on the same limb. All procedures were performed because intermittent claudication did not improve after continuation of antiplatelet medication therapy and home-based exercise for 3 months. Rutherford classification was 2 in 20 limbs and 3 in 74 limbs. Patients with critical limb ischemia were excluded. Median duration of follow-up was 40 months. Primary patency rates of the iliac stent, clinical improvement rates, and risk factors for requiring additional SFA procedures were evaluated. Results. Primary patency rates of the iliac stent at 1, 3, 5, and 7 years were 97, 93, 79, and 79 %, respectively. The initial clinical improvement rate was 87 %. Continued clinical improvement rates at 1, 3, 5, and 7 years were 87, 81, 69, and 66 %, respectively. SFA Trans-Atlantic Inter-Society Consensus (TASC) II C/D lesion was a significant risk factor for requiring additional SFA procedures. Conclusion. Intermittent claudication was relieved by iliac stent placement in most patients with both iliac and SFA lesions. Thus, the indications for treatment of the SFA intended for claudicants should be evaluated after treatment of the iliac lesion.

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Percutaneous Treatment of Iatrogenic Pseudoaneurysms by Cyanoacrylate-Based Wall-Gluing

Purpose. Although the majority of iatrogenic pseudoaneurysms (PSAs) are amenable to ultrasound (US)-guided thrombin injection, patients with those causing neuropathy, claudication, significant venous compression, or soft tissue necrosis are considered poor candidates for this option and referred to surgery. We aimed to test the effectiveness and feasibility of a novel percutaneous cyanoacrylate glue (NBCA-MS)-based technique for treatment of symptomatic and asymptomatic iatrogenic PSA. Material and Methods. During a 3-year period, we prospectively enrolled 91 patients with iatrogenic PSA [total n = 94 (femoral n = 76; brachial n = 11; radial n = 6; axillary n = 1)]. PSA were asymptomatic in 66 % of cases, and 34 % presented with symptoms due to neuropathy, venous compression, and/or soft tissue necrosis. All patients signed informed consent. All patients received NBCA-MS-based percutaneous treatment. PSA chamber emptying was first obtained by US-guided compression; superior and inferior walls of the PSA chamber were then stuck together using NBCA-MS microinjections. Successfulness of the procedure was assessed immediately and at 1-day and 1-, 3-, and 12-month US follow-up. Results. PSA occlusion rate was 99 % (93 of 94 cases). After treatment, mean PSA antero-posterior diameter decrease was 67 {+-} 22 %. Neuropathy and vein compression immediately disappeared in 91 % (29 of 32) of cases. Patients with tissue necrosis (n = 6) underwent subsequent outpatient necrosectomy. No distal embolization occurred, nor was conversion to surgery necessary. Conclusion. PSA treatment by way of NBCA-MS glue injection proved to be safe and effective in asymptomatic patients as well as those with neuropathy, venous compression, or soft-tissue necrosis (currently candidates for surgery). Larger series are needed to confirm these findings.

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Warming Effect on Miriplatin–Lipiodol Suspension as a Chemotherapeutic Agent for Transarterial Chemoembolization for Hepatocellular Carcinoma: Preliminary Clinical Experience

Purpose: To retrospectively elucidate the preliminary clinical impact of warmed miriplatin–lipiodol suspension (MPT-LPD) when used as a chemotherapeutic agent for transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). Materials and Methods: Between June and December 2010, TACE was performed with MPT-LPD at room temperature (RT group), and after January 2011, TACE with MPT-LPD warmed to 40 °C was performed (W group). The intraarterial appearance of MPT-LPD immediately after injection through microcatheters at the second-order branches was compared between the two groups with a 5-point grading system. Local therapeutic effects of HCCs as assessed by follow-up computed tomography (CT) obtained 1–3 months after TACE were compared between the groups with a 4-point grading system (TE1–TE4). After April 2011, angiography-assisted CT was routinely performed at TACE, and HCCs that revealed apparent corona enhancement (CE) were retrospectively selected. The degree of concordance between CE and MPT-LPD accumulation as assessed by CT immediately after TACE was assessed with a 3-point grading scale. Results: MPT-LPD therapy resulted in a smooth and continuous appearance in the W group (grades 1, 2, 3, 4, and 5 were, respectively, 1, 2, 11, 18, and 4) compared to the RT group (4, 0, 1, 2, and 0). The W group (TE1, TE2, TE3, and TE4 were 1, 9, 11, and 12) revealed better local therapeutic effects than the RT group (6, 3, 9, and 0) (p < 0.05). CE was found in 26 HCC nodules, and concordance between CE and MPT-LPD accumulation was observed in 66 % (grades 1, 2, and 3 were, respectively, 2, 8, and 19). Conclusion: Warmed MPT-LPD flowed more smoothly within vascular lumen, passed through tumor sinusoid of HCC, and had better local therapeutic effects at short-term observation than MPT-LPD at room temperature.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Root Cause Analysis of Gastroduodenal Ulceration After Yttrium-90 Radioembolization

Introduction: A root cause analysis was performed on the occurrence of gastroduodenal ulceration after hepatic radioembolization (RE). We aimed to identify the risk factors in the treated population and to determine the specific mechanism of nontarget RE in individual cases. Methods: The records of 247 consecutive patients treated with yttrium-90 RE for primary (n = 90) or metastatic (n = 157) liver cancer using either resin (n = 181) or glass (n = 66) microspheres were reviewed. All patients who developed a biopsy-proven microsphere-induced gastroduodenal ulcer were identified. Univariate and multivariate analyses were performed on baseline parameters and procedural data to determine possible risk factors in the total population. Individual cases were analyzed to ascertain the specific cause, including identification of the culprit vessel(s) leading to extrahepatic deposition of the microspheres. Results: Eight patients (3.2 %) developed a gastroduodenal ulcer. Stasis during injection was the strongest independent risk factor (p = 0.004), followed by distal origin of the gastroduodenal artery (p = 0.004), young age (p = 0.040), and proximal injection of the microspheres (p = 0.043). Prolonged administrations, pain during administration, whole liver treatment, and use of resin microspheres also showed interrelated trends in multivariate analysis. Retrospective review of intraprocedural and postprocedural imaging showed a probable or possible culprit vessel, each a tiny complex collateral vessel, in seven patients. Conclusion: Proximal administrations and those resulting in stasis of flow presented increased risk for gastroduodenal ulceration. Patients who had undergone bevacizumab therapy were at high risk for developing stasis.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

An Assessment of Radiologically Inserted Transoral and Transgastric Gastroduodenal Stents to Treat Malignant Gastric Outlet Obstruction

Introduction: Self-expanding metallic stents (SEMS) are used to palliate malignant gastric outlet obstruction (GOO) and are useful in patients with limited life expectancy or severe medical comorbidity, which would preclude surgery. Stenting can be performed transorally or by a percutaneous transgastric technique. Our goal was to review the outcome of patients who underwent radiological SEMS insertion performed by a single consultant interventional radiologist. Methods: Patients were identified from a prospectively collected database held by one consultant radiologist. Data were retrieved from radiological reports, multidisciplinary team meetings, and the patients’ case notes. Univariate survival analysis was performed. Results: Between December 2000 and January 2011, 100 patients (63 males, 37 females) had 110 gastroduodenal stenting procedures. Median age was 73 (range 39–89) years. SEMS were inserted transorally (n = 66) or transgastrically (n = 44). Site of obstruction was the stomach (n = 37), duodenum (n = 50), gastric pull-up (n = 10), or gastroenterostomy (n = 13). Seven patients required biliary stents. Technical success was 86.4 %: 83.3 % for transoral insertion, 90.9 % for transgastric insertion. Eleven patients developed complications. Median GOO severity score: 1 pre-stenting, 2 post-stenting (p = 0.0001). Median survival was 54 (range 1–624) days. Post-stenting GOO severity score was predictive of survival (p = 0.0001). Conclusions: The technical success rate for insertion of palliative SEMS is high. Insertional technique can be tailored to the individual depending on the location of the tumor and whether it is possible to access the stomach percutaneously. Patients who have successful stenting and return to eating a soft/normal diet have a statistically significant increase in survival.

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