Hepatic Hilar Nerve Block for Adjunctive Analgesia during Percutaneous Thermal Ablation of Hepatic Tumors: A Retrospective Analysis.

PURPOSE: To determine whether hepatic hilar nerve block techniques reduce analgesic and sedation requirements during percutaneous image-guided thermal ablation of hepatic tumors. MATERIALS AND METHODS: A single-center retrospective cohort analysis was performed of 177 patients (median age, 67 years; range, 33-86 years) who underwent percutaneous image-guided thermal ablation of liver tumors. All patients were treated utilizing local anesthetic and moderate sedation between November 2018 and November 2021 at a tertiary level hospital, with or without the administration of a hepatic hilar nerve block. Univariable and multivariable linear regression analyses were performed to determine the relationship between the administration of the hilar nerve block and fentanyl and midazolam dosages. RESULTS: A total of 114 (64%) patients received a hilar nerve block in addition to procedural sedation, and 63 (36%) patients received procedural sedation alone. There were no significant differences in the baseline demographic and tumor characteristics between the cohorts. The procedure duration was longer in the hilar block cohort than in the unblocked cohort (median, 95 vs 82 minutes; P = .0012). The technical success rate (98% in both the cohorts, P = .93) and adverse event rate (11% vs 3%, P = .14) were not significantly different between the cohorts. After adjusting for patient and tumor characteristics, ablation modality, and procedure and ablation durations, hilar nerve blocks were associated with lower fentanyl (-18.4%, P = .0045) and midazolam (-22.7%, P = .0007) dosages. CONCLUSIONS: Hepatic hilar nerve blocks significantly decrease the fentanyl and midazolam requirements during thermal ablation of hepatic tumors, without a significant change in the technical success or adverse event rates.

Interventional radiology: a half century of innovation.

The evolution of modern interventional radiology began over half century ago with a simple question. Was it possible to use the same diagnostic imaging tools that had revolutionized the practice of medicine to guide the real-time treatment of disease? This disruptive concept led to rapid treatment advances in every organ system of the body. It became clear that by utilizing imaging some patients could undergo targeted procedures, eliminating the need for major surgery, while others could undergo procedures for previously unsolvable problems. The breadth of these changes now encompasses all of medicine and has forever changed the way we think about disease. In this brief review article, major advances in the field, as chronicled in the pages of Radiology, will be described.

Thoracic duct embolization and disruption for treatment of chylous effusions: experience with 105 patients.

PURPOSE: To review the indications, technical approach, and clinical outcomes of thoracic duct embolization (TDE) and thoracic duct disruption (TDD) in patients with symptomatic chylous effusions. MATERIALS AND METHODS: A total of 105 patients who underwent 120 consecutive TDE/TDD procedures were retrospectively reviewed. Data including cause of effusion, procedural technique, and pre- and postprocedural effusion volume were analyzed. Technical and clinical success were evaluated for each procedure, with technical success defined as successful interruption of the thoracic duct by embolization or needle disruption and clinical success defined as resolution of effusion without surgical intervention. RESULTS: The technical success rate was 79% (95 of 120); 53 TDEs were performed, resulting in a 72% clinical success rate (n = 38), whereas 42 TDDs showed a 55% clinical success rate (n = 23; P = .13). Procedures to treat postpneumonectomy chylous effusions had a success rate of 82% (14 of 17), compared with 47% (nine of 19) in postpleurectomy subjects (P < .05). Clinically successful cases had lower 24-, 48-, and 72-hour postprocedural effusion volumes versus clinically unsuccessful cases (P < .05), as well as greater rates of reduction in effusion volume at these time points (P < .05). Clinical success rate in subjects with traumatic effusions was higher than in subjects with nontraumatic effusions (62% [60 of 97] vs 13% [one of eight]; P < .05), and 6.7% of subjects (n = 7) experienced minor complications. CONCLUSIONS: TDE and TDD are safe and effective minimally invasive treatments for traumatic thoracic duct injuries. In the present series, factors affecting procedural success included etiology of effusion, postprocedural effusion volume, and rate of postprocedural effusion volume reduction.

Safety and utility of transjugular liver biopsy in hematopoietic stem cell transplant recipients.

PURPOSE: Hematopoietic stem cell transplant (HSCT) recipients are at high risk in the setting of percutaneous liver biopsy as a result of comorbid coagulopathy and ascites, and are commonly referred to undergo transjugular liver biopsy. The present study was performed to assess the safety and utility of transjugular liver biopsy in HSCT recipients and to analyze the correlation between corrected hepatic sinusoidal pressure gradient (CHSPG) and pathologic diagnoses. MATERIALS AND METHODS: Data from reports of transjugular liver biopsy procedures, pathology reports, and laboratory values of 141 consecutive HSCT recipients who underwent transjugular liver biopsy with pressure measurement between January 2005 and August 2011 in a single institution were retrospectively reviewed and analyzed. RESULTS: A total of 166 biopsy procedures were performed in 141 patients. Technical success rate was 98.8%. Biopsy was diagnostic in 95.7% of patients. There were three major complications (1.8%), including one death. CHSPG in patients with venoocclusive disease (VOD) was significantly higher (P<.001) than in those without VOD (16.2 mm Hg±9.2 vs 5.6 mm Hg±3.7). A CHSPG of 10 mm Hg or higher was 90.8% specific and 77.3% sensitive for VOD. CONCLUSIONS: The present data show that transjugular liver biopsy is a relatively safe procedure that provides important information for the clinical management of patients with HSCT. Measurement of CHSPG during the procedure can support the diagnosis of VOD.

ACR Appropriateness Criteria(®) on suspected lower extremity deep vein thrombosis.

Lower extremity deep vein thrombosis (DVT) is a common clinical concern, with an incidence that increases with advanced age. DVT typically begins below the knee but may extend proximally and result in pulmonary embolism. Pulmonary embolism can occur in 50% to 60% of patients with untreated DVT and can be fatal. Although clinical examination and plasma d-dimer blood evaluation can often predict the presence of DVT, imaging remains critical for the diagnostic confirmation and treatment planning of DVT. Patients with above-the-knee or proximal DVT have a high risk for pulmonary embolism and are recommended to receive anticoagulation therapy. On the other hand, patients with below-the-knee or distal DVT rarely experience pulmonary embolism, and anticoagulation therapy in these patients remains controversial. However, one sixth of patients with distal DVT may experience extension of their thrombus above the knee and therefore are recommended to undergo serial imaging assessment at 1 week to exclude proximal DVT extension if anticoagulation therapy is not initiated. Ultrasound is the preferred imaging method for evaluation of patients with newly suspected lower extremity DVT. Magnetic resonance and CT venography can be especially helpful for the evaluation of suspected DVT in the pelvis and thigh. Contrast x-ray venography, the historic gold standard for DVT assessment, is now less commonly performed and primarily reserved for patients with more complex presentations such as those with suspected recurrent acute DVT.

Uterine artery embolization in the treatment of postpartum uterine hemorrhage.

PURPOSE: To evaluate the clinical effectiveness and safety of uterine artery embolization (UAE) in the treatment of primary postpartum hemorrhage (PPH), secondary PPH, and PPH associated with cesarean section. MATERIALS AND METHODS: All women who underwent UAE for obstetric-related hemorrhage during a 52-month period culminating in April 2009 were included. Clinical success was defined as obviation of hysterectomy. Blood product requirements before and after UAE were calculated. Statistically significant associations between subject characteristics and clinical success were evaluated. The two subgroups of women with uterine artery pseudoaneurysms and women who underwent cesarean section were examined separately as well. RESULTS: Sixty-six women (mean age, 33 years; range, 17-47 y) underwent UAE, with an overall clinical success rate of 95% (98% for primary PPH, 88% for secondary PPH, and 94% for PPH associated with cesarean section) and an overall complication rate of 4.5%. Mean pre- and postembolization transfusion requirements were 3.1 U and 0.4 U of packed red blood cells, respectively. The only significant characteristic identified for the cases that necessitated hysterectomy was an increased transfusion requirement after UAE (increase of 1.0 U ± 0.5; P = .02). Uterine artery pseudoaneurysms were associated with secondary PPH (P = .01) and cesarean section (P = .03). CONCLUSIONS: The threshold for UAE in women with PPH should be low, as it is associated with a high clinical effectiveness rate and a low complication rate. Uterine artery pseudoaneurysms should be suspected in women presenting with secondary PPH after cesarean section.

ACR Appropriateness Criteria® on upper gastrointestinal bleeding.

Upper gastrointestinal bleeding is a significant cause of morbidity and mortality, affecting 36 to 48 per 100,000 persons annually. Aggressive resuscitation and upper endoscopy remain the cornerstones of therapy; however, in cases refractory to endoscopic diagnosis and management, radiology plays an increasingly vital and often lifesaving role, thanks to improvements in both imaging and interventional techniques. The various etiologies of upper gastrointestinal bleeding are discussed along with specific management recommendations based on an extensive literature review of current radiographic methods.

Interventional radiology and anesthesia.

Interventional radiology (IR) encompasses a broad and expanding array of image-guided, minimally invasive therapies that are essential to the practice of modern medicine. The growth and diversity of these non-OR procedures presents unique challenges and opportunities to anesthesiologists and interventional radiologists alike. Collaborative action has led to better patient care and quality management. This discussion considers some angiographic and cross-sectional IR procedures in more detail and comments on some of the anesthesia choices and considerations. In addition, specific concerns regarding anesthesia in the area of IR are reviewed.

ACR appropriateness criteria on recurrent symptoms following lower-extremity angioplasty.

Lower-extremity arteriopathy patients can be managed nonsurgically, but there is no standard algorithm for follow-up. The authors present a consensus on appropriate postangioplasty studies in the setting of claudication or a threatened limb. Physical examination with measurements of the ankle-brachial index should be the first step in patients with recurrent symptoms. When there is high clinical suspicion for a threatened limb, the patient should proceed directly to catheter angiography for possible reintervention. However, in the setting of claudication alone, segmental Doppler pressures and pulse volume recordings are the initial test of choice. Magnetic resonance angiography or ultrasound can be used in conjunction to further characterize lesions with more detail. Computed tomographic angiography may also be used to image lower-extremity vasculature but is limited by the presence of large amounts of vascular calcifications. Novel techniques, including dual-energy computed tomographic angiography and noncontrast magnetic resonance angiography, may provide clinicians with alternative approaches in patients with large amounts of vascular calcifications and renal insufficiency, respectively.

Translumbar type II endoleak repair using angiographic CT.

Translumbar embolization of type II endoleaks after endovascular abdominal aneurysm repair has been proved to be effective. One challenge of this approach is the choice of the most suitable image guiding modality. For needle placement, cross-sectional imaging under computed tomographic (CT) guidance is preferable. For embolization, fluoroscopy is the modality of choice for most interventionalists. A new technology can acquire CT-like images by rotating an angiographic, flat-panel detector of a C-arm around the patient. This technology allows a combination of fluoroscopic and CT guidance within the angiographic suite. The authors describe the successful use of a combination of fluoroscopy and angiographic CT in three cases of translumbar type II endoleak embolization.

A new method for aggressive management of deep vein thrombosis: retrospective study of the power pulse technique.

Failure to treat deep vein thrombosis (DVT) is associated with significant morbidity and mortality. Anticoagulation, although effective at preventing clot progression, is not able to prevent postthrombotic syndrome. Catheter-directed thrombolysis is a more aggressive alternative, with some small studies suggesting a better long-term outcome, but the associated risks are significant, and the treatment can require 2-3 days in a monitored setting. This report describes the power pulse technique, in which mechanical thrombectomy is combined with thrombolytic agents to maximize the effectiveness of the treatment and reduce the need for prolonged infusion and its associated risks. A 24-patient retrospective study showed complete thrombus removal (>90%) in 12 patients, substantial thrombus removal (50%-90%) in seven patients, and partial thrombus removal (<50%) in five patients. All 24 patients had resolution of presenting symptoms. Only two patients required blood transfusion, and one patient experienced temporary nephropathy.

Percutaneous treatment of high-output chylothorax with embolization or needle disruption technique.

Surgical ligation of the thoracic duct is associated with a high degree of morbidity; therefore, a minimally invasive approach is desirable. Herein, eight percutaneously treated patients are described. In four patients, the thoracic duct was embolized with use of coils and glue. In the other four patients, lymphatic ducts were disrupted by multiple needle punctures. The median chest tube drainage substantially decreased in both patient groups from more than 1,300 mL the day before the procedure to less than 300 mL 2 days after the procedure. The median times to chest tube removal were 7 days in the embolization group and 3.5 days in the needle disruption group.

Use of CT angiography to classify endoleaks after endovascular repair of abdominal aortic aneurysms.

PURPOSE: Accurate endoleak detection and classification is critical for the follow-up of patients who have undergone endovascular aneurysm repair (EVAR). This determination is often made with computed tomography angiography (CTA). This investigation was performed to determine the accuracy of CTA in the classification of endoleaks in patients who have undergone EVAR. MATERIALS AND METHODS: Thirty-six patients with endoleaks underwent both CTA and conventional contrast digital subtraction angiography (DSA) to determine endoleak etiology. Two independent radiologists determined the source of the endoleak based on a retrospective review of the CTA. The results of the CTA-based endoleak classification were compared to the reference standard, contrast DSA. RESULTS: There was agreement regarding endoleak classification between CTA and DSA on 86% of the patients (31 of 36 patients). Correlation between the CTA reading of the two readers was 94% (34 of 36 patients), yielding a kappa statistic of 0.8. In three patients, the CTA reading incorrectly classified endoleaks as type 2 when the endoleaks were actually type 1 endoleaks on DSA. One patient was incorrectly classified as having a type 1 endoleak on CTA when it was a type 2 endoleak on DSA. Finally, one patient had a type 1 endoleak on DSA that was incorrectly classified as a type 3 endoleak on CTA. The change in CTA endoleak classification based on the DSA resulted in a significant change in patient management in four of the 36 patients (11%). CONCLUSIONS: Endoleak classification based on CTA correlates fairly well with DSA findings. However, optimal endoleak management requires performance of selective angiograms with DSA to classify endoleaks that are detected on CTA.

Catheter-based treatments of endoleaks.

At the present time, patients who have undergone endovascular aneurysm repair require lifelong surveillance. The purpose of this surveillance is threefold. First, has there been any change in the position of the endograft? Secondly, what is the status of the aneurysm sac? Thirdly, is there an endoleak? How the patient is managed depends on the answers to these three questions. Managing patients with endoleaks remains a challenging clinical problem. Decisions on these patients depend on the type of leak and the status of the aneurysm sac. This manuscript will review what is currently known about endoleaks and use this information to develop algorithms of how patients should be treated.

Midterm pivotal trial results of the Talent Low Profile System for repair of abdominal aortic aneurysm: analysis of complicated versus uncomplicated aortic necks.

OBJECTIVE: This study was undertaken to determine whether a complicated aortic neck is associated with unfavorable outcome after abdominal aortic aneurysm (AAA) endografting. METHODS: In a prospective pivotal clinical trial, 237 consecutive patients underwent implantation of the bifurcated Talent Low Profile System. Patients were divided into 2 groups, those with complicated aortic necks (short, <15 mm; very short, < or =10 mm; dilated, >28 mm; angulated, >45 degrees; calcified; and thrombus-lined) versus those with uncomplicated neck anatomy. Major outcome parameters included procedure time, operative blood loss, transfusion requirements, volume of contrast medium used during the implant procedure, endoleaks, migration, limb patency, AAA regression, conversion to open repair, morbidity, and mortality. Mean follow-up was 620.5 days. RESULTS: Overall, 32% of aortic necks were short, 19% were very short, 20% were dilated, 18% were calcified, 8.5% were thrombus-lined, and 19.9% were angulated. Thirty percent and 70% of patients, respectively, were stratified to the uncomplicated and complicated groups ( P < .01. Procedure time, operative blood loss, transfusions, volume of contrast medium used in the implant procedure, migration, endograft patency, AAA sac regression, conversion to open repair, and mortality were not significantly different in necks with complicated versus uncomplicated anatomy. At 21 months, sacs were regressing or stable in 98% (complicated) versus 96% (uncomplicated). Primary graft limb patency was 100% in both groups. The endoleak rate was 4.3% (complicated) versus 17% (uncomplicated) at 18 months, but this difference was not statistically significant. Adverse renal events, however, occurred in 27.5% (complicated) versus 13.6% (uncomplicated; P = .04). CONCLUSIONS: Complicated aortic neck is not associated with unfavorable outcome at midterm follow-up after AAA endografting. However, statistically more adverse renal events occur in patients with complicated neck anatomy.

Imaging modalities for the detection and management of endoleaks.

Although endovascular aneurysm repair (EVAR) has shown promising initial results, there are unique complications to this procedure. Endoleaks, which do not occur after traditional surgical repair of abdominal aortic aneurysms, are detected in patients undergoing EVAR and are thought by some to be one of the limitations of this procedure. Endoleaks may continue to perfuse and pressurize the aneurysm sac, thereby conferring an ongoing risk of aneurysm enlargement and/or rupture. Because of this, accurate endoleak detection and classification is essential following EVAR. Surveillance of patients is critical to determine the long-term performance of the stent grafts. Although this is usually accomplished with contrast-enhanced spiral computed tomography scans performed at regular intervals, duplex ultrasonography exams; magnetic resonance angiography; and digital subtraction angiography all have a role in endoleak detection and classification. This article will cover imaging modalities used to detect endoleaks. In addition, we will cover which imaging exams should be performed to help with endoleak management.

Chemoembolization of liver metastasis from breast carcinoma.

Chemoembolization was performed in eight patients with liver metastasis from breast carcinoma. Five of eight patients had some radiographic regression of the liver tumors, one had stable liver disease, and two had disease progression. Two of four patients with pain showed clinical improvement of their symptoms. Only one patient with radiographic response or disease stabilization subsequently had intrahepatic progression (at 3 months). Five patients developed other metastasis, particularly brain metastasis, at a mean of 4.6 months after first chemoembolization (range, 2-12 months). All patients died within 13 months of treatment, with a mean survival of 49 months from primary diagnosis, 20 months from liver metastasis diagnosis, and 6 months from first chemoembolization.

MR angiography with gadofosveset trisodium for peripheral vascular disease: phase II trial.

PURPOSE: To evaluate the dose response and safety of gadofosveset trisodium-enhanced magnetic resonance (MR) angiography compared with nonenhanced two-dimensional time-of-flight MR angiography and with x-ray angiography as the standard. MATERIALS AND METHODS: In this randomized, 20-center, double-blind study, 238 men and women who had peripheral vascular disease or were suspected of having it received intravenous injection of placebo or gadofosveset (0.005, 0.01, 0.03, 0.05, or 0.07 mmol per kilogram of body weight). MR angiographic images were evaluated by three blinded readers, and x-ray angiographic images were evaluated by two readers. Hypothesis testing for the presence of a dose response was based on a linear test for trend for increase in area under the receiver operating characteristic curve as a function of dose for each reader of MR angiographic images independently. RESULTS: Gadofosveset administration resulted in a dose-dependent increase in diagnostic accuracy for detection of aortoiliac occlusive disease as reflected in the area under the receiver operating characteristic curve for each reader (P <.001). The plateau in effectiveness improvement began at the 0.03 mmol/kg dose. At doses of 0.03 mmol/kg and higher, gadofosveset-enhanced MR angiography provided an approximate 20% increase in accuracy over nonenhanced MR angiography for diagnosis of clinically significant aortoiliac occlusive disease. Gadofosveset exhibited a good safety profile in all dose groups. Three serious adverse events were possibly or probably related to gadofosveset administration. There were no dose-related trends in severe or serious adverse events in patients receiving gadofosveset. CONCLUSION: A dose of 0.03 mmol/kg of gadofosveset was safe and effective for evaluation of aortoiliac occlusive disease with MR angiography.