Inline Balloon Occlusion-Assisted Delivery of Ethylene Vinyl Alcohol Copolymer for Peripheral Arterial Applications: A Multicenter Case Series.

PURPOSE: To assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications. MATERIALS AND METHODS: Six academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11-94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1-5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications. RESULTS: Balloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred. CONCLUSIONS: Balloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s).

Effect of Full Correction Versus Partial Correction of Elevated Blood Glucose in the Emergency Department on Hospital Length of Stay.

There is limited information to guide the extent to which asymptomatic hyperglycemia needs to be corrected in patients presenting to the emergency department (ED) with unrelated complaints. The objective of this study was to compare full correction (FC) versus partial correction (PC) of elevated blood glucose in the ED on hospital length of stay. This was a retrospective cohort study conducted in an academic ED in the United States. Adult diabetic patients with hyperglycemia (blood glucose >200 mg/dL) in the ED who were treated with subcutaneous insulin were included. Patients were categorized based on the level of blood glucose control achieved within the first 24 hours from triage: (1) FC group for whom blood glucose <200 mg/dL was achieved or (2) PC group for whom blood glucose remained ≥200 mg/dL. The primary outcome measure was a comparison of hospital length of stay between groups. A total of 161 patients were included in this study (FC = 81, PC = 80). There was no significant difference between hospital length of stay in the FC [3 days (interquartile range, 1-5 days)] and PC [3 days (interquartile range, 2-6 days)] groups (P = 0.159). In the multivariate analysis, after adjusting for potential confounders, there was no significant association between level of correction and hospital length of stay (log-transformed) (coefficient 0.238; 95% confidence interval, -0.062 to 0.537; P = 0.119; R = 13%). The extent of glucose correction was not associated with a decrease in hospital length of stay in diabetic patients with hyperglycemia in the ED.

Beyond hemostasis: spectrum of gynecologic and obstetric indications for transcatheter embolization.

Percutaneous vascular embolization is a useful therapeutic option for a wide range of gynecologic and obstetric abnormalities. Transcatheter embolization procedures performed with the use of radiologic imaging for guidance are minimally invasive and may obviate surgery, thereby decreasing morbidity and mortality and safeguarding the patient's future fertility potential. To integrate this treatment method optimally into patient care, knowledge is needed about the clinical indications for therapeutic embolization, the relevant vascular anatomy, technical considerations of the procedure, and the potential risks and benefits of embolization. The most well-known and well-studied transcatheter embolization technique for treating a gynecologic-obstetric condition is uterine fibroid embolization. However, the clinical indications for transcatheter embolization are much broader and include many benign gynecologic conditions, such as adenomyosis and arteriovenous malformations, as well as intractable bleeding due to inoperable advanced-stage malignancies. Uterine artery embolization may be performed to prevent or treat bleeding associated with various obstetric conditions, including postpartum hemorrhage, placental implantation abnormality, and ectopic pregnancy. Embolization of the uterine artery or the internal iliac artery also may be performed to control pelvic bleeding due to coagulopathy or iatrogenic injury, and ovarian vein embolization has been shown to be effective for the management of pelvic congestion syndrome. The article discusses these and other gynecologic and obstetric indications for transcatheter embolization, provides detailed descriptions of imaging findings before and after embolization, and reviews procedural techniques and outcomes.

Thermal ablation of osteoid osteoma: overview and step-by-step guide.

Osteoid osteoma is a small, benign but painful lesion with specific clinical and imaging characteristics. Computed tomography is the imaging modality of choice for visualization of the nidus and for treatment planning. Complete surgical excision of the nidus is curative, providing symptomatic relief, and is the traditionally preferred treatment. However, surgery has disadvantages, including the difficulty of locating the lesion intraoperatively, the need for prolonged hospitalization, and the possibility of postoperative complications ranging from an unsatisfactory cosmetic result to a fracture. Percutaneous radiofrequency (RF) ablation, which involves the use of thermal coagulation to induce necrosis in the lesion, is a minimally invasive alternative to surgical treatment of osteoid osteoma. With reported success rates approaching 90%, RF ablation should be considered among the primary options available for treating this condition.

Role of contrast-enhanced ultrasound (CEUS) in evaluation of thermal ablation zone.

PURPOSE: Thermal ablation has emerged as a mainstay therapy for primary and metastatic liver malignancy. Percutaneous thermal ablation is usually performed under CT and/or ultrasound guidance. CT guidance frequently utilizes iodinated contrast for tumor targeting, with additional radiation and contrast required at the end of the procedure to ensure satisfactory ablation margins. Contrast-enhanced ultrasound (CEUS) is an imaging technique utilizing microbubble contrast agents to demonstrate blood flow and tissue perfusion. In this study, we performed a retrospective review to assess the utility of CEUS in the immediate post ablation detection of residual tumor. METHODS: Sixty-four ablations were retrospectively reviewed. 6/64 ablations (9.4%) had residual tumor on the first follow-up imaging after thermal ablation. There were two groups of patients. Group 1 underwent standard protocol thermal ablation with CT and/or ultrasound guidance. Group 2 not only had thermal ablation with a protocol identical to group 1, but also had CEUS assessment at the conclusion of the procedure to ensure satisfactory ablation zone. RESULTS: The residual tumor rate in group 1 was 16.7% and the residual tumor rate in group 2 was 0%. The difference between the groups was statistically significant with a p value of 0.023. The results suggest that using CEUS assessment immediately after the ablation procedure reduces the rate of residual tumor after thermal ablation. CONCLUSION: CEUS evaluation at the end of an ablation procedure is a powerful technique providing critical information to the treating interventional radiologist, without additional nephrotoxic contrast or ionizing radiation.

Prospective evaluation of vascular complications after liver transplantation: comparison of conventional and microbubble contrast-enhanced US.

PURPOSE: To prospectively compare diagnostic performance of conventional Doppler ultrasonography (US) and microbubble contrast material-enhanced US for assessment of vascular complications after liver transplantation, with clinical follow-up or angiography as reference standard. MATERIALS AND METHODS: This study was approved by institutional review board and was HIPAA compliant. Written informed consent was obtained. Seventy-two patients (49 men, 23 women; average age, 52.3 years) were included in this study. Patients who had undergone liver transplantation underwent conventional color Doppler and contrast-enhanced US of the liver. Quality of hepatic artery (HA) and portal vein (PV) visualization, contrast material arrival time, and time for complete evaluation of vasculature were compared for both techniques. McNemar test was used to compare vascular flow visualization scores; Student t test was used to compare mean study times with both techniques. Patients without HA flow at Doppler US underwent angiography; those with flow were followed up clinically. McNemar test was used to compare sensitivity of both techniques. RESULTS: Contrast-enhanced US helped significantly improve flow visualization in hepatic vessels (P < .001). Mean contrast material arrival time was 13.7 seconds +/- 3.8 (standard deviation) in proper HA and 20.7 seconds +/- 6.3 in PV. Mean study time decreased from 27.4 minutes +/- 13.9 to 9.3 minutes +/- 4.5 (P < .01). Doppler US failed to depict HA flow in eight patients; contrast-enhanced US showed flow in six and no flow in two of these patients. Follow-up results confirmed contrast-enhanced US findings. Sensitivity, specificity, and accuracy for Doppler US were 91.3%, 100%, and 91.5%, respectively. Sensitivity, specificity, and accuracy of contrast-enhanced US were all 100%. Sensitivity and accuracy values of the two techniques were significantly different (P < .014); there was no significant difference in specificity (P > .99) CONCLUSION: Contrast-enhanced US helped improve flow visualization in the HA and PV, decrease scanning time, and correctly differentiate between thrombosis and a patent artery in patients without HA flow at conventional Doppler US.

N-butyl cyanoacrylate embolization for control of acute arterial hemorrhage.

PURPOSE: To report the initial clinical experience with the use of n-butyl cyanoacrylate (NBCA) for embolization of acute arterial hemorrhage from varied etiologies and at varied anatomic sites. MATERIALS AND METHODS: Sixteen patients who demonstrated active extravasation of contrast material and/or arterial abnormality underwent NBCA embolization. Sites of embolization included the gastrointestinal tract, kidney, liver, uterus, adrenal gland, extremity, and chest wall. Standard coil or particulate embolization had previously failed in 10 patients. NBCA was used as the initial embolic agent in the remaining six patients. After treatment, serial hematocrit levels, transfusion requirements, and clinical signs and symptoms were monitored for stabilization. Patients were evaluated for signs and symptoms of end-organ damage. RESULTS: NBCA embolization was successful in 12 of 16 patients (75%), who exhibited complete cessation of bleeding. In four patients (25%), NBCA embolization was of no benefit. Embolization failed in two of 16 patients (12.5%), who showed evidence of recurrent bleeding after use of NBCA. The remaining two patients (12.5%) died within 24 hours of the procedure. None of the 16 patients developed clinical signs of end-organ damage or iatrogenic ischemia attributable to NBCA. CONCLUSIONS: In this initial limited series, NBCA embolization was shown to be a feasible and effective method to control acute arterial hemorrhage. NBCA embolization was able to stop arterial bleeding even when previous coil or particulate embolization had failed.