Volumetric ablation of uterine fibroids using Sonalleve high-intensity focused ultrasound in a 3 Tesla scanner--first clinical assessment.

INTRODUCTION: The purpose of this study was to evaluate the feasibility and safety of the Sonalleve high-intensity focused ultrasound (HIFU; Philips Healthcare, Vantaa, Finland) system in ablating uterine fibroids in a 3T magnet. MATERIAL AND METHODS: Seven women were included in this study. Treatment was performed according to the manufacturer's recommendation. Technical data describing the HIFU procedures were collected. On MR images at baseline, immediately and 30 days after ablation, we evaluated the volumes of the uterus, the dominant fibroid and the ablation zone. The Uterine Fibroid Symptom and Quality of Life (UFS-QOL) questionnaire was used to assess potential clinical response. RESULTS: The procedure was technically feasible in all patients. The median number of sonications performed during each procedure was 20 (range 2-27) per patient, the maximum temperature in all sonication cells was about 68°C. The median procedure time was 156 minutes (range 95-164). The non-perfused volume after treatment ranged from 1 to 27 ml and was unchanged or decreased in all but one patient at 30 days follow-up. There were no major adverse events. DISCUSSION: In our 3T magnet the system was able to heat tissue and induce areas of non-enhancement within uterine fibroids without major complications. Clinical benefit remains to be proven.

Improved infarction rates in fibroids after the introduction of contrast-enhanced ultrasound during uterine artery embolization.

BACKGROUND: In order to achieve sustained symptom control and minimize the risk of recurrence, uterine artery embolization (UAE) should aim at complete infarction of all fibroids. PURPOSE: To retrospectively evaluate the infarction rate of uterine fibroids in patients that had undergone uterine artery embolization (UAE) after the introduction of contrast-enhanced ultrasound (CEUS) during UAE procedures at our institution. MATERIAL AND METHODS: Thirty patients treated with UAE between February 2006 and August 2009 were included. MR images obtained before, at 3 months, and 12 months after the procedure were reviewed. We evaluated volume changes in dominant fibroids as well as the infarction rate of all fibroids in each patient. Clinical results were evaluated by reviewing the medical records. The study was approved by the institutional review board. RESULTS: CEUS was technically successfully performed during the UAE procedure in all patients. In five cases the endpoint of embolization was adjusted based on findings at CEUS. The mean volume shrinkage of dominant fibroids was 39.8% after 3 months and 59.8% after 12 months. There was complete infarction of all fibroid tissue in 97% of patients at 3 months and 96% at 12 months. No major complications were observed. CONCLUSION: After the introduction of CEUS during UAE procedures in our institution, high infarction rates were achieved.

Contrast enhanced ultrasound in the detection of liver metastases: a prospective multi-centre dose testing study using a perfluorobutane microbubble contrast agent (NC100100).

OBJECTIVE: To conduct a dose testing analysis of perfluorobutane microbubble (NC100100) contrast-enhanced ultrasound (CEUS) to determine the optimal dose for detection of liver metastases in patients with extra-hepatic primary malignancy. METHODS: 157 patients were investigated with conventional US and CEUS. CEUS was performed following intravenous administration of perfluorobutane microbubbles (using one dose of either 0.008, 0.08, 0.12 or 0.36 µL/kg body weight). Three blinded off-site readers recorded the number and locations of metastatic lesions detected by US and CEUS. Contrast enhanced CT and MRI were used as the "Standard Of Reference" (SOR). Sensitivity, specificity and accuracy of liver metastasis detection with US versus CEUS, for each dose group were obtained. Dose group analysis was performed using the Chi-square test. RESULTS: 165 metastases were present in 92 patients who each had 1-7 lesions present on the SOR. Sensitivity of US versus CEUS (for all doses combined) was 38% and 67% (p = 0.0001). The 0.12 dose group with CEUS (78%) had significantly higher sensitivity and accuracy (70%) compared to other dose groups (p < 0.05). CONCLUSION: The diagnostic performance of CEUS is dose dependent with the 0.12 µL/kg NC100100 dose group showing the greatest sensitivity and accuracy in detection of liver metastases.

Assessment of renal allograft fibrosis by acoustic radiation force impulse quantification--a pilot study.

Chronic allograft nephropathy characterized by interstitial fibrosis and tubular atrophy is a major cause of renal transplant failure. Acoustic radiation force impulse (ARFI) quantification is a promising noninvasive method for assessing tissue stiffness. We evaluated if the method could reveal renal transplant fibrosis. In a prospective study, 30 adult renal transplant recipients were included. ARFI quantification, given as shear wave velocity (SWV), of the renal cortex was performed by two observers. SWV was compared to grade of fibrosis (0-3) in biopsies. The median SWV was 2.8 m/s (range: 1.6-3.6), 2.6 m/s (range: 1.8-3.5) and 2.5 m/s (range: 1.6-3) for grade 0 (n = 12), 1 (n = 10) and grades 2/3 (n = 8) fibrosis respectively. SWV did not differ significantly in transplants without and with fibrosis (grade 0 vs. grade 1, P = 0.53 and grade 0 vs. grades 2/3, P = 0.11). The mean intraobserver coefficient of variation was 22% for observer 1 and 24% for observer 2. Interobserver agreement, expressed as intraclass correlation coefficient was 0.31 (95% CI: -0.03 to 0.60). This study does not support the use of ARFI quantification to assess low-grade fibrosis in renal transplants. ARFI quantification in its present stage of development has also high intra- and interobserver variation in renal transplants.

Reducing the risk of iodine-based and MRI contrast media administration: recommendation for a questionnaire at the time of booking.

This paper presents a practical questionnaire to be used when a contrast medium examination is requested. The questionnaire is based on the guidelines from the European Society of Urogenital Radiology. Its aim is to identify patients at increased risk of clinically relevant renal and non-renal adverse reactions to iodine-based and MRI contrast agents. The questionnaire should be completed by the referring physician when the examination is requested.

The feasibility of contrast-enhanced ultrasound during uterine artery embolization: a pilot study.

PURPOSE: To evaluate the feasibility of using contrast-enhanced ultrasound (CEUS) during uterine artery embolization (UAE) in order to define the correct end-point of embolization with complete devascularization of all fibroids. METHODS: In this prospective study of 10 consecutive women undergoing UAE, CEUS was performed in the angiographic suite during embolization. When the angiographic end-point, defined as the "pruned-tree" appearance of the uterine arteries was reached, CEUS was performed while the angiographic catheters to both uterine arteries were kept in place. The decision whether or not to continue the embolization was based on the findings at CEUS. The results of CEUS were compared with those of contrast-enhanced magnetic resonance imaging (MRI) 1 day as well as 3 months following UAE. RESULTS: CEUS was successfully performed in all women. In 4 cases injection of particles was continued based on the findings at CEUS despite angiographically complete embolization. CEUS imaging at completion of UAE correlated well with the findings at MRI. CONCLUSION: The use of CEUS during UAE is feasible and may increase the quality of UAE.

Safety of ultrasound contrast agents.

The use of ultrasound contrast agents has increased over recent years. The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) decided to review the safety of ultrasound contrast agents in humans and to draw up guidelines. A comprehensive literature search and review was carried out. The resulting report was discussed by the CMSC of ESUR and at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela, Spain, in 2004. Ultrasound contrast agents approved for clinical use are well tolerated, and serious adverse reactions are rarely observed. Adverse events are usually minor (e.g. headache, nausea, altered taste, sensation of heat) and self-resolving. These symptoms may not be related to the ultrasound contrast materials as they have also been observed in placebo-control groups. Intolerance to some components may occur. Generalized allergy-like reactions occur rarely. Ultrasound contrast agents are generally safe. The ultrasound scanning time and the acoustic output should be kept to the lowest level consistent with obtaining diagnostic information. Adverse reactions should be treated symptomatically.

Contrast medium extravasation injury: guidelines for prevention and management.

Extravasation of contrast material is a well-recognized complication of contrast-enhanced imaging studies. The management of this complication is contentious; therefore, the Contrast Media Safety Committee of The European Society of Urogenital Radiology decided to review the literature and issue guidelines. A comprehensive literature search was carried out. The resulting report was discussed at the 8th European Symposium on Urogenital Radiology in Genoa, Italy. Automated power injection may result in extravasation of large volumes and may or can lead to severe tissue damage. Infants, young children and unconscious and debilitated patients are particularly at risk of extravasation during contrast media injection. Fortunately, most extravasations result in minimal swelling or erythema, with no long-term sequelae; however, severe skin necrosis and ulceration may occur. Large volumes of high osmolar contrast media are known to induce significant tissue damage. Compartment syndrome may be seen associated with extravasation of large volumes. Conservative management is often adequate, but in serious cases the advice of a plastic surgeon is recommended. Based on the review simple guidelines for prophylaxis and management of contrast medium extravasation injuries are proposed.