Stem Cell-Based Therapies: What Interventional Radiologists Need to Know.

As the basic units of biological organization, stem cells and their progenitors are essential for developing and regenerating organs and tissue systems using their unique self-renewal capability and differentiation potential into multiple cell lineages. Stem cells are consistently present throughout the entire human development, from the zygote to adulthood. Over the past decades, significant efforts have been made in biology, genetics, and biotechnology to develop stem cell-based therapies using embryonic and adult autologous or allogeneic stem cells for diseases without therapies or difficult to treat. Stem cell-based therapies require optimum administration of stem cells into damaged organs to promote structural regeneration and improve function. Maximum clinical efficacy is highly dependent on the successful delivery of stem cells to the target tissue. Direct image-guided locoregional injections into target tissues offer an option to increase therapeutic outcomes. Interventional radiologists have the opportunity to perform a key role in delivering stem cells more efficiently using minimally invasive techniques. This review discusses the types and sources of stem cells and the current clinical applications of stem cell-based therapies. In addition, the regulatory considerations, logistics, and potential roles of interventional Radiology are also discussed with the review of the literature.

Pregnancy success and outcomes after uterine fibroid embolization: updated review of published literature.

Females with symptomatic leiomyomas (fibroids) wishing to maintain fertility are faced with difficult treatment choices. These include uterine fibroid embolization (UFE), myomectomy, hormonal therapy, MRI high intensity focused ultrasound, and myolysis. This review focuses on UFE, one of the most commonly accepted minimally invasive procedural choices among patients with symptomatic fibroids wishing to retain the option of becoming pregnant in the future, and makes comparisons to myomectomy which has historically been the surgical choice for fertility-preserving fibroid treatment. Pubmed and Google Scholar searches using keywords such as: uterine artery embolization, uterine fibroid embolization, pregnancy, complications, infertility were performed between Jan 1, 2019 and May 10, 2019. Publications were chosen based on their inclusion of information pertaining to fertility or pregnancy after UFE without being limited to single case reports.Randomized controlled trials comparing myomectomy and UFE are limited due to study size and confounding variables, but through registry data and familiarity with referring clinicians, UFE has gained wide acceptance. Healthy pregnancies following UFE have been sporadically reported but the actual fertility rate after UFE remains uncertain. Conversely, low birth weight, miscarriage and prematurity have been associated with UFE. Despite inherent risks of possible fertility issues after UFE, the procedure remains an option for females with clinically symptomatic fibroids who desire pregnancy. However, additional research regarding rates of conception and obstetrical risks of infertility following UFE is necessary.

Successful percutaneous computed tomography guided drainage of mediastinal abscess in esophageal perforation.

Esophageal perforation with subsequent development of a mediastinal abscess is a well-known clinical entity. Etiologies including idiopathic and iatrogenic with invasive procedures have been reported in medical literatures. This condition is seriously associated with high co-morbidity and in some cases especially if intervention has not been applied associated with high mortality. For long time, open surgical intervention was the only available treatment modality for esophageal perforation with subsequent development of a mediastinal abscess. However, recently there are some other less invasive modalities that have been used with comparable if not preferable success including; self-expandable metallic or plastic stents and imaging guided percutaneous drainage of the mediastinal abscess combined with stenting. We report a patient who presented with esophageal perforation complicated with a mediastinal abscess that was treated successfully with an imaging guided percutaneous drainage of the mediastinal abscess. This case is to emphasize on the fact that endoscopic stent placement is safe and effective for esophageal perforations. Percutaneous CT-guided drainage of associated mediastinal abscesses is an uncommon procedure, but the results suggest that it is associated with high technical and clinical success rates. There should be increased involvement of interventional radiology in the management of those cases.

Intravascular forward-looking ultrasound transducers for microbubble-mediated sonothrombolysis.

Effective removal or dissolution of large blood clots remains a challenge in clinical treatment of acute thrombo-occlusive diseases. Here we report the development of an intravascular microbubble-mediated sonothrombolysis device for improving thrombolytic rate and thus minimizing the required dose of thrombolytic drugs. We hypothesize that a sub-megahertz, forward-looking ultrasound transducer with an integrated microbubble injection tube is more advantageous for efficient thrombolysis by enhancing cavitation-induced microstreaming than the conventional high-frequency, side-looking, catheter-mounted transducers. We developed custom miniaturized transducers and demonstrated that these transducers are able to generate sufficient pressure to induce cavitation of lipid-shelled microbubble contrast agents. Our technology demonstrates a thrombolysis rate of 0.7 ± 0.15 percent mass loss/min in vitro without any use of thrombolytic drugs.

Long-term outcomes of the bronchial artery embolization are diagnosis dependent.

BACKGROUND: Bronchial artery embolization (BAE) is an established, safe, and effective procedure for the treatment of hemoptysis but long-term outcomes of the BAE have never been investigated before. OBJECTIVES: To retrospectively analyze long-term outcomes of the BAE. MATERIALS AND METHODS: A retrospective chart analysis was done from the hospital central database for all patients undergoing the BAE over a consecutive 14-year period (January 2000-February 2014). A total of 58 patients were identified from the database. Eight patients were excluded due to the lack of follow-up. Data such as patient demographics, reason for hemoptysis, medical imaging results, bronchoscopy findings, recurrence rates, and morbidity/mortality rates after the BAE were collected. RESULTS: Eighty three embolizations were performed in 50 patients. The median follow-up was of 2.2 years. Cystic fibrosis (CF) bronchiectasis was the most common etiology (21/50), followed by non-CF bronchiectasis (9/50). Cavitary lung disease occurred in 12/50 patients, an additional 4/50 had cancer (primary lung and metastatic), and one patient had antineutrophil cytoplasmic antibody (ANCA) vasculitis. In three patients the etiology was unknown. Postprocedural complications occurred in 5/83 (6%) patients, two patients with two major complications - stroke (one) and paraplegia (one) - and three patients with minor complications - chest pain (two) and bronchial artery dissection (one). A total of 15/50 patients died during the follow-up. Three patients died of hemoptysis, and the remaining deaths were unrelated to the procedure or hemoptysis. Twenty four patients had recurrent hemoptysis. A Kaplan-Meier analysis revealed an excellent long-term survival that was 85% at 10 years. CONCLUSIONS: The BAE is a safe and effective procedure with excellent overall long-term survival.

Conversion of Percutaneous Cholecystostomy to Internal Transmural Gallbladder Drainage Using an Endoscopic Ultrasound-Guided, Lumen-Apposing Metal Stent.

Patients with acute cholecystitis sometimes require placement of percutaneous cholecystostomy catheters, either as a bridge to surgery or as primary therapy. In patients who cannot undergo surgery, subsequent removal of the catheter can lead to recurrence of cholecystitis, whereas leaving the drain in place can cause adverse events. We investigated internalization of percutaneous cholecystostomy drainage catheters, using endoscopic ultrasound (EUS)-guided placement of lumen-apposing metal stents (LAMS) as an alternative treatment strategy. Seven patients (median age, 57 years; 6 men) underwent EUS-guided cholecystoenterostomy for internalization of gallbladder drainage with EUS-guided placement of a 10- or 15-mm LAMS. All had initially been treated with placement of a percutaneous cholecystostomy catheter for cholecystitis and were later deemed unfit for cholecystectomy. Technical success was achieved in all patients in 1 endoscopic session, with subsequent removal of all percutaneous drains. Two patients required placement of self-expandable metal stents within the LAMS to successfully bridge the gallbladder and gastrointestinal lumen. No adverse events occurred after a median follow-up of 2.5 months. EUS-guided cholecystoenterostomy using a LAMS is therefore a viable option for internal gallbladder drainage in patients who have a percutaneous cholecystostomy catheter and are poor candidates for cholecystectomy.

Effectiveness of Initial Transarterial Chemoembolization for Hepatocellular Carcinoma Among Medicare Beneficiaries.

BACKGROUND: Optimal administration of transarterial chemoembolization (TACE), the standard approach for intermediate-stage hepatocellular carcinoma (HCC), requires clinical and technical expertise. We sought to evaluate whether TACE retains its effectiveness when administered across a broad range of health care settings. Furthermore, as the use of yttrium(90) (Y(90)) radioembolization has been increasing, we explored the comparative effectiveness of Y(90) as an alternative to TACE. METHODS: Patients with HCC diagnosed from 2004 through 2009 treated initially with TACE or Y(90) were identified from the SEER-Medicare linkage. Key covariates included prediagnosis α-fetoprotein (AFP) screening, complications of cirrhosis, and tumor extent. Effect of treatment, patient, and health care system factors on overall survival (OS) was evaluated using multivariable Cox proportional hazards. Stratified OS estimates are provided. Propensity score (PS) weighting was used to compare effectiveness of Y(90) with TACE. RESULTS: Of 1528 patients who underwent intra-arterial embolization, 577 received concurrent chemotherapy (eg, TACE). Median OS was 21 months (95% CI, 18-23) following TACE and 9 months (95% CI, 1-41) following Y(90). Refined survival estimates stratified by stage, AFP screening, and liver comorbidity are presented. The 90-day mortality rate after TACE was 21% to 25% in patients with extrahepatic spread or vascular invasion. In the PS-weighted analysis, Y(90) was associated with inferior survival, with an adjusted hazard ratio of 1.39 (95% CI, 1.02-1.90). CONCLUSIONS: The effectiveness of TACE is generalizable to Medicare patients receiving care in a variety of treatment settings. However, early posttreatment mortality is high in patients with advanced disease. We found no evidence of improved outcomes with Y(90) compared with TACE. Survival estimates from this large cohort can be used to provide prognostic information to patients considering palliative TACE.

Interventional radiologic management and treatment of enterocutaneous fistulae.

Enterocutaneous fistulae (ECFs) are abnormal sinus tract communications between the alimentary system and skin surface that can cause significant management problems and cost to the health care system. Interventional radiology can play an important role in diagnosis and treatment when conventional measures fail and additional surgery is difficult or poses a high risk. The management of patients with fistulae requires operator ingenuity and dedication, a multidisciplinary team approach, and an understanding of the pathophysiology. This article reviews the major issues in ECF management and the role of interventional radiology.

Bone and soft tissue ablation.

Bone and soft tissue tumor ablation has reached widespread acceptance in the locoregional treatment of various benign and malignant musculoskeletal (MSK) lesions. Many principles of ablation learned elsewhere in the body are easily adapted to the MSK system, particularly the various technical aspects of probe/antenna design, tumoricidal effects, selection of image guidance, and methods to reduce complications. Despite the common use of thermal and chemical ablation procedures in bone and soft tissues, there are few large clinical series that show longitudinal benefit and cost-effectiveness compared with conventional methods, namely, surgery, external beam radiation, and chemotherapy. Percutaneous radiofrequency ablation of osteoid osteomas has been evaluated the most and is considered a first-line treatment choice for many lesions. Palliation of painful metastatic bone disease with thermal ablation is considered safe and has been shown to reduce pain and analgesic use while improving quality of life for cancer patients. Procedure-related complications are rare and are typically easily managed. Similar to all interventional procedures, bone and soft tissue lesions require an integrated approach to disease management to determine the optimum type of and timing for ablation techniques within the context of the patient care plan.

The role of interventional radiology in management of benign and malignant gynecologic diseases.

This article focuses on the role of interventional radiology in the therapeutic and diagnostic management of benign and malignant gynecologic conditions. The subspecialty of interventional radiology utilizes minimally invasive advanced image-guided percutaneous techniques in gynecology that include central venous catheter placement, fluid aspiration, drainage catheter placement, tissue biopsy, inferior vena cava filter placement, and pelvic arterial embolization. Central venous catheters, such as ports, peripherally inserted central catheters, and tunneled catheters, are placed for intermediate to long-term intravenous chemotherapy or total parental nutrition or antibiotics. Patients with refractory malignant ascites or pleural effusion from seeding of advanced gynecologic cancers may benefit by percutaneous aspiration of fluid collections or placement of drainage catheters. Postoperative fluid collections including abscess, seroma, or lymphocele are managed by percutaneous drainage catheter insertion. Pelvic, peritoneal, or retroperitoneal masses can be sampled by image-guided percutaneous biopsy or aspiration of fluid to determine a pathologic diagnosis. Certain patients are at risk for deep venous thrombosis with pulmonary embolism and may benefit from an inferior vena cava filter. Patients with uncontrolled postoperative or postpartum bleeding can be effectively managed with emergent transarterial pelvic embolization. Each of the aforementioned interventions with indications, expected benefits, and complications is described including a published literature.

Central Venous Line Placement prior to Gastric Bypass Improves Operating Room Efficiency.

Background. Bariatric surgery has increased across America. Venous access is difficult in these patients. Anesthesiologists often utilize valuable operating room (OR) time acquiring reliable intravenous lines. Our objective was to determine if outpatient central venous line (CVL) placement improves OR efficiency and professional reimbursement for CVL insertion. Methods. In our bariatric practice, selected surgery patients have outpatient CVLs placed during prophylactic vena cava filter placement. In a cohort of 268 gastric bypass patients operated between 1/01 and 11/06, we compared time-to-incision between 106 with pre-established CVLs and 162 without. In addition, we determined professional compensation rates for CVLs placed outpatient versus CVLs inserted in the OR. Results. Patients with preoperative (outpatient) CVLs required 35.6 ± 12.5 minutes to skin incision compared with 42.5 ± 13.9 minutes for controls (P < 0.0001), and 34.9% had skin incision in <30 minutes compared with 16.4% of controls. Radiologists collected 28.2% of outpatient billings for CPT code 36556, compared with anesthesiologists who collected <1% when placing CVLs in the OR. Conclusions. Outpatient CVLs prior to gastric bypass improve efficiency in the OR with earlier skin incision. Professional reimbursement is better for outpatient CVLs than intraoperative inpatient CVLs.

Utilization of interventional radiology in the postoperative management of patients after surgery for locally advanced and recurrent rectal cancer.

The surgical management of locally advanced primary rectal cancer and locally recurrent rectal cancer requires complex operations frequently resulting in complicated postoperative courses. We sought to evaluate the utilization of interventional radiologic (IR) procedures in the management of postoperative complications. Under Institutional Review Board approval, a prospective database of colorectal cancer patients undergoing resection from July 1999 to January 2010 was analyzed. Data collected included demographics, operative procedure, complications, length of stay, and IR utilization. Fisher's exact tests and logistic regression explored associations with necessitating an IR procedure during the postoperative period. Continuous variables were analyzed using Wilcoxon rank sum tests. One hundred and one patients underwent surgery and 66 received intraoperative electron radiotherapy (IOERT). Primary procedures included pelvic exenteration (n = 35), abdominoperineal resection (n = 25), low anterior resection (n = 23), paraaortic node dissection (n = 7), resection of isolated pelvic/retroperitoneal tumor (n = 7), and colectomy (n = 4). Sixty-two patients required multivisceral resection including partial/total cystectomy (n = 30), small bowel resection (n = 25), oophorectomy (n = 15), vaginectomy (n = 12), hysterectomy (n = 12), hepatectomy (n = 3), and nephrectomy (n = 3). Seventeen partial sacral resections and 47 pelvic sidewall resections were also required. One hundred and thirty-eight complications were identified in 72 patients, 30 of which required a procedural intervention. Twenty-seven IR procedures were performed including drainage of fluid collections (n = 14), nephrostomy tube placement (n = 8), arterial embolization (n = 2), inferior vena cava filter placement (n = 2), and pleural drainage (n = 1). Only three reoperations were required, none related to failure of IR procedures. There were no deaths. Estimated blood loss > 2000 mL (P = 0.002), IOERT (P = 0.03), and incomplete resection (P = 0.02) were found to be associated with postoperative IR utilization. Surgery for locally advanced primary rectal cancer and locally recurrent rectal cancer is associated with significant morbidity but low mortality. IR procedures play a significant role in the postoperative management of these patients and may decrease the need for reoperation.

Temporary balloon tamponade for managing subclavian arterial injury by inadvertent central venous catheter placement.

PURPOSE: To evaluate the feasibility, efficacy, and safety of a temporary balloon tamponade technique for managing subclavian arterial injury secondary to inadvertent central venous catheter placement. MATERIALS AND METHODS: Patients with subclavian arterial injury caused by inadvertent placement of a central venous catheter (size range 7-F to 7.5-F) who were treated only with temporary balloon tamponade between February 2002 and October 2009 were included. A temporary balloon tamponade technique was used to treat 13 patients (6 men and 7 women; mean age 56.7 years; age range 28-80 years). Technical success, total balloon inflation time, and complications were evaluated. RESULTS: Technical success was achieved with the temporary balloon tamponade technique in 13 cases (100%). Eight patients were treated with one balloon inflation, and five patients with two inflations (mean inflations 1.4). The mean total balloon inflation time was 14 minutes ± 13. There was no recurrent bleeding, hematoma, or pseudoaneurysm that required additional interventional procedures or surgical repair. A thrombus was identified in the subclavian arterial lumen after removal of the balloon catheter in one case; however, the thrombus was nonocclusive and asymptomatic. CONCLUSIONS: Temporary balloon tamponade seems to be technically feasible and effective with a good safety profile in the management of subclavian arterial injury caused by inadvertent central venous catheter placement. Intraluminal thrombus can be an associated complication of the procedure.

Congenital tracheobiliary fistula combined with hypoplastic common hepatic duct: Management by percutaneous transhepatic drainage.

Congenital tracheobiliary or bronchobiliary fistula is a rare developmental anomaly with a persistent communication between the biliary system and the trachea or bronchus. We report a case of a congenital tracheobiliary fistula and hypoplastic common hepatic duct associated with hypoplastic left heart syndrome in a 5-day old boy presenting with bilious endotracheal-tube secretions. The tracheobiliary fistula was treated by surgical resection. Subsequent cholangiography demonstrated dilated intrahepatic bile ducts and a residual fistulous tract with cystic proximal stump that were successfully decompressed by transhepatic drainage catheters before corrective biliary surgery.

Use of yttrium-90 microspheres in patients with advanced hepatocellular carcinoma and portal vein thrombosis.

PURPOSE: Patients with portal vein thrombosis (PVT) and hepatocellular carcinoma (HCC) have limited treatment options because of increased disease burden and diminished hepatic perfusion. Yttrium-90 ((90)Y) microspheres may be better tolerated than chemoembolization in these patients. The present study reviews the safety and efficacy of (90)Y microspheres in HCC with major PVT. MATERIALS AND METHODS: A retrospective review of HCC with main (n = 10) or first-branch (n = 12) PVT treated with (90)Y microspheres (N = 22) was conducted. Cancer of the Liver Italian Program (CLIP) scores ranged from 2 to 5, with 18% of patients having a score of 4 or greater. Imaging response at 8-12 was based on Response Evaluation Criteria In Solid Tumors. Overall survival (OS) was estimated by the Kaplan-Meier method. RESULTS: A total of 32 microsphere treatments (26 glass, six resin) were administered to 22 patients. Common grade 1/2 toxicities included abdominal pain (38%), nausea (28%), and fatigue (22%). Four posttreatment hospitalizations occurred, all less than 48 hours in duration. One death occurred 10 days after therapy. The partial response rate was 8% and progressive disease was seen in 42% of patients. Stable disease was achieved in 50% of treatments. Median OS was 7 months from initial treatment. Patients with Child-Pugh class A disease had a median OS of 7.7 months; those with class B/C disease had an OS of 2.7 months (P = .01). Median OS for patients with CLIP scores of 2/3 was 7 months, versus 1.3 months for those with scores of 4/5 (P = .04). CONCLUSIONS: Yttrium-90 microspheres are tolerated in patients with HCC and major PVT. Compared with chemoembolization, rates of severe adverse events appear low. Radiographic response rates are low. The median OS of 7 months is promising and warrants further study versus systemic therapy.