Role of Locoregional Therapies in the Treatment of Thyroid Pathology: Proceedings from the Society of Interventional Radiology Foundation Research Consensus Panel.

The role of locoregional therapy in the management of thyroid pathology is rapidly evolving. The Society of Interventional Radiology Foundation commissioned an international research consensus panel consisting of physicians from multiple disciplines with expertise in the management of benign and malignant thyroid disease. The panel focused on identifying gaps in the current body of literature to establish research priorities that have the potential to shape the landscape of minimally invasive thyroid interventions. The topics discussed were centered on the emerging role of ablation for malignant thyroid tumors and the treatment of large functioning nodules with embolization and ablation. Specifically, the panel prioritized identifying nodule characteristics, including size and location, that are associated with ideal outcomes following thermal ablation for papillary thyroid microcarcinoma through the development of an international registry or a prospective, multi-institutional trial. The panel also prioritized evaluating the role of locoregional therapy in Stage T1b papillary thyroid cancer through a sequence of two studies: a Phase I study of ablation followed by immediate resection of Stage T1b papillary thyroid cancer, which may lead to a Phase II prospective, multi-institutional study of ablation followed by biopsy for Stage T1b papillary thyroid cancer. Lastly, the panel prioritized investigating the treatment of large, functioning thyroid nodules greater than 20 ml in volume through a randomized clinical trial or prospective registry comparing embolization alone with embolization followed by ablation.

Pre-operative uterine artery embolization before hysterectomy or myomectomy: a single-center review of 53 patients.

PURPOSE: To assess outcomes of planned pre-operative uterine artery embolization (UAE) in patients with uterine fibroids at high risk for bleeding prior to hysterectomy or myomectomy. MATERIALS & METHODS: A retrospective review of 53 consecutive patients who underwent planned UAE followed by surgery from 2004 to 2019 was performed in a subset of patients deemed high risk for bleeding by the referring surgeon due to bulky fibroids and/or adhesions. Characteristics of the largest fibroid, total number of fibroids, embolic agents, estimated blood loss (EBL), complications, and other factors were collected. RESULTS: 53 patients (mean age = 41) had an elective UAE prior to a hysterectomy 24 (45%) or myomectomy 29 (55%). Median interval between UAE & surgery was 21.6 h (range 1.75 h-57 days). Of the myomectomies, 13 (45%) were open, 15 (52%) hysteroscopic and 1 laparoscopic. Mean number of fibroids/patient was 4.1 (SD 1.3), mean fibroid volume was 328 cm3 (range 11-741), and the mean fibroid diameter in longest dimension was 7.4 cm (range 3.2-15). Mean EBL was 90 (SD 99.5 mL). Three (10%) myomectomy patients required blood transfusion. All hysterectomies were via a laparotomy. Mean fibroid volume was 1699 cm3 (range 93-9099 cm3) with a mean maximum diameter of 16.2 cm (range 6.5-29.6) and an average of 2.4 (SD 1.7) fibroids. Mean EBL was 352 (SD 220 mL). Four (17%) hysterectomy patients required an intra- or post-operative blood transfusion. At a mean 1-year follow-up (range 1 month-14 years), 70% of UAE-myomectomy patients and 74% of UAE-hysterectomy patients reported symptom resolution. Three (6%) patients were readmitted: one for osteodiscitis, one wound dehiscence, and one for an infected retained fibroid after myomectomy. CONCLUSION: Planned pre-operative UAE resulted in intraoperative blood loss similar to "all-comer" myomectomy and hysterectomy patients in the literature. Further studies may elucidate which patients would be the best candidates for this staged treatment paradigm.

Effect of computed tomography angiography prior to bronchial embolization on radiation dose and recurrent hemoptysis.

PURPOSE: To investigate whether pre-procedure Computed Tomography Angiography (CTA) improves radiation exposure, procedure complexity, and symptom recurrence after bronchial embolization for massive hemoptysis. MATERIAL AND METHODS: A single-center retrospective review of bronchial artery embolization (BAE) for massive hemoptysis was performed for procedures between 2008 and 2019. Multi-variate analysis was performed to determine the significance of pre-procedure CTA and etiology of hemoptysis on patient radiation exposure (reference point air kerma, RPAK) and rate of recurrent hemoptysis. RESULTS: There were 61 patients (mean age 52.5 years; SD = 19.2 years, and 57.3% male) and CTA was obtained for 42.6% (26/61). Number of vessels selected was a mean of 7.2 (SD = 3.4) in those without CTA and 7.4 (SD = 3.4) in those with CTA (p = 0.923). Mean procedure duration was 1.8 h (SD = 1.6 h) in those without CTA and 1.3 h (SD = 1.0 h) in those with CTA (p = 0.466). Mean fluoroscopy time and RPAK per procedure were 34.9 min (SD = 21.5 min) and 1091.7 mGy (SD = 1316.6 mGy) for those without a CTA and 30.7 min (SD = 30.7 min) and 771.5 mGy (SD = 590.0 mGy) for those with a CTA (p = 0.523, and p = 0.879, respectively). Mean total iodine given was 49.2 g (SD = 31.9 g) for those without a CTA and 70.6 g (SD = 24.9 g) for those with a CTA (p = 0.001). Ongoing hemoptysis at last clinical follow up was 13/35 (37.1%) in those without CTA and 9/26 (34.6%) in those with CTA (p = 0.794). CONCLUSIONS: Pre-procedure CTA did not improve radiation effective dose and symptom recurrence after BAE and is associated with significant increases in total iodine dose.

Management of Pancreatico-duodenal arterio-venous malformation.

PURPOSE: To describe the interventional management and clinical outcome of pancreatico-duodenal arterio-venous malformations (PDAVMs). MATERIAL AND METHODS: Seven patients presenting a PDAVM (6 women, 1 male; mean age: 61) were retrospectively reviewed. Technical, clinical success and complications of embolization and surgical management of symptomatic PDAVMs were assessed. Technical success was defined as a complete occlusion of the PDAVM and clinical success as no clinical symptom or recurrence during follow-up. Patients with asymptomatic PDAVMs were followed clinically, by Doppler ultrasound and CT-angiography. RESULTS: Mean follow-up time was 69 months (15-180). Five symptomatic patients presented with upper gastrointestinal bleeding (n=3), ascites (n=1), and abdominal pain (n=1). Two patients were asymptomatic. The PDAVMs were classified as follow: Yakes I (1), IIIa (2), IIIb (3) and IV (1). Five symptomatic patients were treated with 9 embolization sessions with arterial approach (onyx®, glue, coils) in 7 and venous approach in 2 (plugs, coils, covered stents, STS foam and onyx®). Technical success of embolization was 60% (3/5). Devascularization was incomplete for 2 Yakes IIIB patients. Clinical success of embolization was estimated at 80% (4/5) as one patient required additional surgery (Whipple) because of persistent bleeding. One splenic vein thrombosis was treated successfully by mechanical thrombectomy and heparin. No recurrence occurred during follow-up. No progression was documented in asymptomatic patients. CONCLUSION: Embolization of symptomatic PDAVMs is effective and surgery should be performed in second intention. Complete devascularization is more difficult to obtain in Yakes III PDAVM.

Spontaneous Rectus Sheath Hematoma: Factors Predictive of Conservative Management Failure.

PURPOSE: To evaluate radiographic, laboratory, and clinical factors associated with conservative management (CM) failure in spontaneous rectus sheath hematoma (RSH). MATERIALS AND METHODS: Retrospective review of 72 patients with spontaneous RSH between 2006 and 2017 was performed. Patients were initially managed conservatively and then divided into 2 groups based on decision to embolize. No differences were found between embolization (n = 32) and CM (n = 40) groups in age (67.5 vs 69.5 y; P = .79), sex (31% vs 38% male; P = .58), body mass index (27.7 vs 25.7 kg/m2; P = .20), or medical comorbidities. Univariate analyses compared initial hemoglobin level, change in hemoglobin level, coagulation parameters, transfusion requirements, hematoma volume, and active extravasation on computed tomographic (CT) angiography between groups. Multivariable logistic regression identified factors predictive of CM failure. A scoring system was then created to predict CM failure. RESULTS: CM failed in 32 of 72 patients. Multivariable regression identified active extravasation on CT angiography (P = .02), hematoma volume (P = .01), and packed red blood cell (pRBC) transfusion of ≥ 4 U (P = .03) as predictors of embolization. A scoring system using these factors along with maximum rate of hemoglobin decrease yielded a sensitivity of 100% and specificity of 98% in determining need for embolization. CONCLUSIONS: CM for RSH was more likely to fail in patients with active extravasation on CT angiography, larger hematoma volume, pRBC transfusion of ≥ 4 U, and higher rate of hemoglobin decrease. Using these parameters, a scoring system was created that achieved high sensitivity and specificity in identifying patients who would require embolization.

Modified Balloon-Occluded Retrograde Transvenous Obliteration (BRTO) Techniques for the Treatment of Gastric Varices: Vascular Plug-Assisted Retrograde Transvenous Obliteration (PARTO)/Coil-Assisted Retrograde Transvenous Obliteration (CARTO)/Balloon-Occluded Antegrade Transvenous Obliteration (BATO).

Gastric varices in the setting of portal hypertension occur less frequently than esophageal varices but occur at lower portal pressures and are associated with more massive bleeding events and higher mortality rate. Balloon-occluded retrograde transvenous obliteration (BRTO) of gastric varices has been well documented as an effective therapy for portal hypertensive gastric varices. However, BRTO requires lengthy, higher-level post-procedural monitoring and can have complications related to balloon rupture and adverse effects of sclerosing agents. Several modified BRTO techniques have been developed including vascular plug-assisted retrograde transvenous obliteration, coil-assisted retrograde transvenous obliteration, and balloon-occluded antegrade transvenous obliteration. This article provides an overview of various modified BRTO techniques.

Midterm Follow-up of Ureteral Embolization Using Vascular Plugs and N-Butyl Cyanoacrylate Glue.

This is a retrospective study of 9 consecutive female patients who underwent ureteral embolization via a "sandwich" technique with two vascular plugs and N-butyl cyanoacrylate glue for ureteral fistulae unresponsive to urinary diversion. Average age was 61 years (range, 39-77 y), average duration of diversion was 48 days (range, 2-120 d), and average follow-up was 11 months (range, 4-23 mo). Seven patients (78%) experienced immediate resolution of urinary leakage, and the other 2 (22%) required unilateral repeat treatment for resolution of leakage. Symptom resolution lasted throughout the follow-up period for all patients. Bilateral internal iliac artery pseudoaneurysms developed in 1 patient and were treated with embolization and stent placement.

Thyroid Radiofrequency Ablation: Updates on Innovative Devices and Techniques.

Radiofrequency ablation (RFA) is a well-known, effective, and safe method for treating benign thyroid nodules and recurrent thyroid cancers. Thyroid-dedicated devices and basic techniques for thyroid RFA were introduced by the Korean Society of Thyroid Radiology (KSThR) in 2012. Thyroid RFA has now been adopted worldwide, with subsequent advances in devices and techniques. To optimize the treatment efficacy and patient safety, understanding the basic and advanced RFA techniques and selecting the optimal treatment strategy are critical. The goal of this review is to therefore provide updates and analysis of current devices and advanced techniques for RFA treatment of benign thyroid nodules and recurrent thyroid cancers.

Factors Related to Late False Lumen Enlargement after Thoracic Stent-Graft Placement for Type B Aortic Dissection.

PURPOSE: To evaluate significant factors related to delayed aortic false lumen (FL) enlargement in patients who have undergone thoracic stent-graft placement for type B aortic dissection. MATERIALS AND METHODS: The study included 62 patients (45 male, 17 female) aged 26-80 years (mean age, 58.1 y) who underwent thoracic endovascular aortic repair for type B aortic dissection at a single institution between January 2005 and May 2015. Mean age of aortic dissections was 5.3 months (range, 0.1-73.3 mo). Maximum aortic diameter at presentation was 41.7 mm ± 8.3. The follow-up period ranged from 3 to 104 months (mean, 27.1 mo). Computed tomographic (CT) angiography studies were reviewed to identify FL diameter enlargements > 5 mm at different levels along and distal to the stent graft. Imaging findings and clinical variables were investigated to determine their correlation with FL enlargement. RESULTS: No significant difference was found between the ages of aortic dissections in patients with and without FL enlargement (P = .26). On follow-up CT angiography, 16 patients had 2 or more communication channels between the FL and the systemic circulation, 7 of whom showed FL enlargement > 5 mm (P = .007). Twenty-seven patients showed complete FL thrombosis, none of whom had FL enlargement (P < .001). CONCLUSIONS: Two or more communication channels between the FL and the systemic circulation represent a risk factor for FL enlargement regardless of the age of the dissection. Patients with thrombosis of the FL are less likely to experience FL enlargement.

Treatment of type II endoleak using Onyx with long-term imaging follow-up.

PURPOSE: The purpose of our study is to report our experience with the use of an ethylene vinyl alcohol copolymer (Onyx) in an off-label fashion for the treatment of type II endoleak after endovascular repair of the thoracic (TEVAR) and abdominal (EVAR) aorta. METHODS: A retrospective review of patients with type I and/or II endoleak treated with Onyx was performed. Data regarding the technical, clinical, and imaging outcomes were collected. Technical success was defined as decreased or eliminated endoleak on the first imaging follow-up. Clinical success was defined as unchanged or decreased aneurysm sac size on subsequent follow-up. RESULTS: Eighteen patients (15 male, 3 female) with a mean age of 79 years (range 69-92) met inclusion criteria (16 abdominal aortic aneurysm, 2 thoracic aortic aneurysm). Sixteen patients had type II endoleak, and 2 had complex type II endoleak with a type I component. The interval between endograft placement and treatment was a mean of 30 months. Direct sac treatment approach was used in 13 patients; transarterial approach was used in 3 patients. Seven patients required the use of coils, N-butyl cyanoacrylate glue, or Amplatzer vascular plugs. The average volume of Onyx used per treatment was 5.6 mL (range 2.5-13). Duration of imaging follow-up was 0.75-72.5 months (mean 32.8). Sixteen of 18 (88.9 %) patients had initial technical and clinical success. Two of 18 patients (11.1 %) were initial technical failures, and 1 remained a failure despite a second treatment and attempted surgical ligation. Eight of 18 (44.4 %) of patients eventually required a second intervention, 5 (27.8 %) of them due to delayed clinical failure. Complications included 1 psoas hematoma, 1 transient L2 nerve paresis, and 1 intraperitoneal Onyx leak; all of these were without clinical sequelae. CONCLUSION: Onyx with or without coil/glue/Amplatzer plug embolization is safe and useful in the treatment of type II endoleak after TEVAR and EVAR. However, long-term clinical and imaging follow-up is needed for early detection and management of recurrence of the primary endoleak or the development of new, secondary endoleaks or enlargement of the aneurysm sac.

Ten frequently asked questions about MRI evaluation of soft-tissue vascular anomalies.

OBJECTIVE: The objective of this article was to address 10 frequently asked questions that radiologists face when planning, performing, and interpreting an MRI study in a patient with a soft-tissue vascular anomaly. CONCLUSION: MRI permits a comprehensive assessment of vascular anomalies. It is important for radiologists to be familiar with the classification and correct nomenclature of vascular anomalies as well as the MRI protocol and distinct imaging findings of the different vascular malformations and tumors.

Extrahepatic pseudoaneurysms and ruptures of the hepatic artery in liver transplant recipients: endovascular management and a new iatrogenic etiology.

PURPOSE: To characterize extrahepatic pseudoaneurysm regarding incidence and etiology and determine the effectiveness of endovascular management. METHODS: A retrospective audit of 1,857 liver transplants in two institutions was performed (1996-2009). Recipients' demographics, clinical presentation, transplant type, biliary anastomosis, and presence of biliary endoprostheses were noted. Pseudoaneurysms were classified into iatrogenic (associated with biliary endoprosthesis or angioplasty) or spontaneous extrahepatic pseudoaneurysms. Spontaneous and iatrogenic pseudoaneurysms were compared for time from transplant, presenting symptoms, location in the arterial anatomy, and 3-month graft survival. Arterial patency and 6-month graft survival were calculated. RESULTS: Twenty pseudoaneurysms were found (1.1 %, 20/1,857): 9 (0.5 % of transplants, 9/1,857) were spontaneous and 11 (0.6 % of transplants, 11/1,857) were "iatrogenic" (due to minimally invasive procedures: 4 angioplasty and 7 biliary endoprostheses). Sixty percent (12/20) underwent endovascular management (4 coil embolization and 8 stent-grafts). Technical success was 83 % (10/12) with a mean arterial patency of 70 % (follow-up mean, 4.9; range, 0-18 months). The 1-, 3-, and 6-month graft survival was 70, 40, and 35 %, respectively. CONCLUSIONS: Due to minimally invasive procedures, posttransplant extrahepatic pseudoaneurysms are no longer an exclusive complication of the transplant surgery itself. Endovascular management is effective to stabilize patients but has not improved historic postsurgical graft survival.

CT imaging findings and their relevance to the clinical outcomes after stent graft repair of penetrating aortic ulcers: six-year, single-center experience.

PURPOSE: To present the computed tomographic (CT) imaging findings and their relevance to clinical outcomes related to stent graft placement in patients with penetrating aortic ulcers (PAUs). METHODS: Medical and imaging records and imaging studies were reviewed for consecutive patients who underwent stent graft repair of a PAU. The distribution and characteristics of the PAU, technical success of stent graft repair, procedure-related complications, associated aortic wall abnormalities, and outcomes of the PAUs at follow-up CT scans were evaluated. RESULTS: Fifteen patients underwent endovascular treatment for PAU. A total of 87% of the PAUs were in the proximal (n = 8) or distal (n = 5) descending thoracic aorta. There was a broad spectrum of PAU depth (mean, 7.9 ± 5.6 mm; range 1.5-25.0 mm) and diameter (mean, 13.5 ± 9.7 mm; range 2.2-41.0 mm). Atherosclerosis of the thoracic aorta and intramural hematoma were associated in 53 and 93% of the patients, respectively. Technical success was achieved in 100%. Two or more stent grafts were used in five patients. Endoleaks were observed in two patients within 2 weeks of the procedure, both of which resolved spontaneously. At follow-up CT scanning, regression and thrombosis of the PAUs were observed in all patients. The average patient survival was 61.8 months, with an overall mortality of 13% (2 of 15) at follow-up. Neither death was related to the endograft device or the PAU. CONCLUSION: Endovascular stent graft placement was safe and effective in causing regression and thrombosis of PAUs in this small series of patients. Two or more stent grafts were used in five patients (33%) with associated long-segmental atherosclerotic changes of the thoracic aorta or intramural hematoma.

MR imaging of soft-tissue vascular malformations: diagnosis, classification, and therapy follow-up.

Vascular malformations and tumors comprise a wide, heterogeneous spectrum of lesions that often represent a diagnostic and therapeutic challenge. Frequent use of an inaccurate nomenclature has led to considerable confusion. Since the treatment strategy depends on the type of vascular anomaly, correct diagnosis and classification are crucial. Magnetic resonance (MR) imaging is the most valuable modality for classification of vascular anomalies because it accurately demonstrates their extension and their anatomic relationship to adjacent structures. A comprehensive assessment of vascular anomalies requires functional analysis of the involved vessels. Dynamic time-resolved contrast material-enhanced MR angiography provides information about the hemodynamics of vascular anomalies and allows differentiation of high-flow and low-flow vascular malformations. Furthermore, MR imaging is useful in assessment of treatment success and establishment of a long-term management strategy. Radiologists should be familiar with the clinical and MR imaging features that aid in diagnosis of vascular anomalies and their proper classification. Furthermore, they should be familiar with MR imaging protocols optimized for evaluation of vascular anomalies and with their posttreatment appearances. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.315105213/-/DC1.