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Abstracts 1020 Long-term follow-up results of HIFU in the treatment of patients with solid malignancy Wu F, Chongqing Medical University, China The ideal treatment of localized cancer should cause the complete death of tumour cells without damage to surrounding normal tissue. In the past two decades, technological advances have initiated a change from open surgery towards less invasive techniques for the local treatment of tumours. Laparoscopic surgery and minimally-invasive ablative techniques, such as radiofrequency, microwave, laser and cryosurgery, have replaced many open surgical procedures in the treatment of patients with malignant disease, with an associated reduction in cost, morbidity and hospital stay. High intensity focused ultrasound (HIFU) is a novel technology in local cancer treatment. It can induce complete coagulation necrosis of a targeted tumour at depth through the intact skin. The concept of HIFU as a noninvasive tool for the replacement of a surgical scalpel for the local destruction of diseased tissue dates back more than 60 years. Recently, dramatic developments in medical imaging techniques have driven the new resurgence of interest in HIFU technique as a potential therapy for solid tumours. To date, both B-mode ultrasonography and magnetic resonance imaging (MRI) are, respectively, incorporated into HIFU devices to guide therapeutic procedures. Much of the clinical application is very recent, and this has obviously changed scientific attitude towards local cancer therapy from the minimally-invasive modalities to the noninvasive therapy. The purpose of this article is to introduce our clinical applications of using ultrasound-guided HIFU in the treatment of solid malignancies in China, including those of liver, breast, bone, kidney, pancreas, soft tissue and uterine. Model-JC HIFU therapeutic system (Chongqing Haifu [HIFU] Tech Co. Ltd., China) is used in the treatment of these carcinomas. There are two goals of HIFU in the treatment of patients with solid malignancy. The primary goal, in patients with localized cancer, is to effect a cure. The other goal is when HIFU is used for palliation of patients with advanced-stage cancer. HIFU can be clinically used as a debulking ablation to provide effective local tumour control, and to improve the quality of life such as pain relief in the palliative setting of end-stage carcinomas. In the clinical trials histopathological examination shows that the treated tumours present clear evidence for cellular destruction of cancer cells and small tumour vascular vessels. Follow-up radiological examinations such as enhanced-CT, enhanced-MRI and contrast ultrasound reveal that there is no blood supply immediately after HIFU ablation, indicating the complete coagulation necrosis of treated tumours. SPECT shows no uptake of radioisotope in osteosarcoma and breast cancer immediately after HIFU. These results indicate a positive therapeutic response and an absence of viable tumour cells. Five-year follow-up data are observed in patients with hepatocellular carcinoma, osteosarcoma and breast cancer after HIFU treatment. Among patients treated with HIFU, an extremely low major complication rate is observed. In conclusion, our multiple clinical studies indicate that HIFU treatment is a safe, effective and feasible modality in the treatment of solid malignancies. These results are exciting and encouraging, but multiple-central, randomized clinical trials worldwide are necessary to fully determine the true efficacy of this noninvasive therapeutic modality. 1021 Treatment of prostate cancer with high intensity focused ultrasound: Clinical application in Korea Lee HM, Samsung Medical Center, Sungkyunkwan University School of Medicine, Korea The effects of high intensity focused ultrasound (HIFU) for localized prostate cancers have been demonstrated during the last decade. Even

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though radical prostatectomy has been considered for mainstay treatment in patients with organ confined prostate cancer, it is still associated with considerable operation-related morbidities. HIFU is capable of causing coagulation necrosis in the targeted tissue by the heat and cavitation effect. Previous literatures described that HIFU treatment is a valuable option for well- and moderately-differentiated localized prostate cancers as well as for local recurrence after external beam radiation therapy. We present the early results of HIFU as a single session in the patients with clinically localized prostate cancer. A total of 58 patients were treated using the Ablatherm HIFU device with or without transurethral resection of the prostate (TURP). HIFU failure was defined as remnant cancer on repeated biopsies or three consecutive increases in the prostate-specific antigen (PSA) ⱖ 1.0 ng/ml. The mean follow-up was 14 months (range, 6 to 21 months). After HIFU treatment, 78% of the total patients had decreased PSA level to ⬍0.5 ng/ml within three months. The median value of last PSA was 0.6 ng/ml and the median nadir PSA was 0.2 ng/ml. The success rates of HIFU were in 85%, 77% and 47% in low, intermediate and high risk groups, respectively. The HIFU failure was closely associated with clinical stage cancer on TURP chips, nadir PSA on univariate analysis. However, the only significant predictor for predicting HIFU failure was nadir PSA value on multivariate Cox regression analysis. The operation-related complications are minimal. Although both the period and number of patients were limited to evaluate the clinical efficacy, HIFU appears to be an encouraging treatment modality in selected patients with prostate cancer. 1022 Treatment of uterine myoma with MR guided focused ultrasound: Clinical application in Japan Murakami T, Okada A, Osaka University Graduate School of Medicine, Japan; Iseikai Hospital, Japan Focused ultrasound (FUS) treatment is an alternative thermal ablation method. Ultrasound is a form of vibrational energy that propagates a mechanical wave molecular motion within a medium. Due to their short wavelength (1.5 mm at 1 MHz), ultrasound beams can be focused with radiators, lenses or reflectors to accurately target well-defined sites and produce localized high temperatures without the need to insert a probe. This localized heating causes well-defined areas of coagulative necrosis, while sparing overlaying and surrounding tissues, making FUS an extremely noninvasive thermal ablation technique. Lynn et al. first investigated the effectiveness of focused ultrasound in 1942. Since then, ultrasound-guided FUS has been used therapeutically in several organs. However, ultrasound guidance does not allow precise target definition, accurate focal spot control or measurement of temperature elevation in the treated tissue. As a solution to these problems, magnetic resonance (MR) imaging has been used to guide and control FUS beginning in the 1990s. MR imaging provides high sensitivity for localizing tumors, excellent anatomic resolution for precise targeting and temperature sensitivity for measuring temperature elevation in treated tissue. The technical feasibility of performing FUS with MR imaging to guide and monitor therapy has been established in both animal experiments and clinical trials. We will introduce the principles and therapeutic methods of MR imaging-guided FUS, and also show our clinical applications and data of uterine fibroid. Fifty-eight patients with symptom of uterine fibroid such as hypermenorrhea and compression underwent FUS treatment and could be followed up for one year. Thirty-nine of the 58 patients (69%) showed an improvement of symptom three months after the treatment, and 35 of them (66%) showed improvement of symptom six mo after. Twenty-one patients underwent the second session of FUS treatment within 12 mo after an initial treatment (three to six mo after in five patients, and six to eight mo in 16 patients. At 12 months after the initial FUS treatment, 43 of the 58

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Ultrasound in Medicine and Biology

patients (74%) showed improvement of symptom. All of the patients with more than 50% of volume of the uterine fibroid coagulated by FUS showed improvement of symptom. Uterine fibroid showing heterogenous high intensity on T2-weighted images due to hyalinization or hemorrhage, or that located 15 cm far from the abdominal wall, was resistive to FUS treatment. In patients with thick subcutaneous fat layer or intraperitoneal fat, it was hard to coagulate uterine fibroid completely. All patients underwent FUS treatment only with intravenous anesthesia, and could be discharged from the hospital on the same day or one day after the treatment. No patient showed ovarian dysfunction due to FUS; 8.9% patients showed skin burn, but no major complication was seen. Our preliminary results suggested that minimum-invasive MR-guided FUS was a feasible, safe and promising treatment for uterine fibroid. Sunday, May 28, 2006 REFRESHER COURSES

ABDOMINAL ULTRASOUND 1023 Ultrasound of vascular problems in the liver Cosgrove D, Hammersmith Hospital, United Kingdom of Great Britain and Northern Ireland Vascular problems in the liver affect both the two venous systems and the artery; most can be assessed with Doppler while contrast enhancement is sometimes very helpful. Portal hypertension may result in spectacular changes, e.g., flow reversal or recanalisation of the umbilical vein. However, milder cases may not be detectable. Portal vein (PV) thrombosis may be bland or malignant,3 ; ?? the latter distinguished by arterial signals of neovascularisation within the thrombus. Flow into the liver may be restored via collaterals called cavernous transformation. The hepatic artery (HA) enlarges in portal hypertension. HA aneurysms and pseudoaneurysms may complicate liver transplantation. HA thrombosis is a serious complication of transplantation because the biliary tree depends on it for oxygenation. When it is difficult to diagnose with Doppler, enhancement with a contrast agent is often definitive. Occlusion of the hepatic veins (HV) leads to the Budd-Chiari syndrome. When this is acute, it carries a high mortality but if only one or two veins are affected or if the process is gradual and allows the inferior group of HVs to enlarge, the typical features of absent or thready HVs, sometimes with reversed flow, may be demonstrated. The dilated inferior HVs may be obvious. There is often secondary thrombosis of the PV. Occlusion of hepatic venules is a feature of veno-occlusive disease; these vessels are too small to give Doppler signals but the process may lead to hepatofugal PV flow. Rarer conditions of interest include hereditary haemorrhagic telangectasia and peliosis hepatis. 1024 Don’t get “stumped” by the biliary tree Laing F, Brigham and Women’s Hospital: Harvard University, United States of America INTRAHEPATIC BILE DUCTS A Dilated intrahepatic bile ducts (look for “double ducts”). (1) Altered portal anatomy in 100% of cases. Other findings: stellate confluence of tubular structures (70%); irregular walls (60%); acoustic enhancement (60%). (2) False negative: (23% of cases)—with early obstruction; stiff liver. (3) False positive: (unusual)—with large hepatic artery (seen with portal hypertension; hepatic neoplasms).

Volume 32, Number 5S, 2006 INTRAHEPATIC PATHOLOGIES A. Intrahepatic neoplasms (1) Metastatic disease. (2) Primary tumors— cystadenoma/cystadenocarcinoma; cholangiocarcinoma. B. Caroli disease (1) Probably autosomal recessive. (2) Two forms. a. Childhood form: associated with severe hepatic fibrosis, portal hypertension, choledochal cysts, IPCKD; (b) pure form: diverticulum-like sacculi of the intrahepatic biliary tree with communication between the sacs and bile ducts. Ddx ⫽ polycystic liver disease. C. Cholangitis and conditions associated with intrahepatic biliary echoes (1) Pneumobilia. a. Etiology ⫽ interventions (stents/tubes, papillotomy, biliary-enteric anastamosis); b. US appearance can be very subtle. Focal or linear echoes; left lobe ⬎ right lobe. (2) Recurrent pyogenic cholangitis (RPC). a. Etiology ⫽ bile stasis ⱖ infection ⱖ bile deconjugation ⱖ soft stones. b. US appearance Intrahepatic calculi (GB spared) with variable echogenicity and variable acoustic shadowing. (3) Cholangitis. a. Primary sclerosing cholangitis: US ⱖ abnormally thick, echogenic portal triad. b. AIDC cholangiopathy: US ⱖ BD wall thickening and distal CBD stricture. Other findings ⫽ GB wall thickening, periductal lucency. EXTRAHEPATIC BILE DUCT A. Duct size: ⬍ 5mm ⫽ normal; 6 to 7 mm ⫽ equivocal; ⬎8 mm ⫽ dilated (1) Don’t include wall in measurement. (2) With a funneled appearance (extrahepatic duct large; normal duct at porta) a. Ddx ⫽ Low cystic duct insertion, early obstruction, remote obstruction, diffuse liver disease (metastases/cirrhosis). (3) With borderline size duct, give a fatty meal. a. Normal response ⫽ duct gets smaller. b. Abnormal response ⫽ duct gets larger. 4. False negative CBD dilatation: Cholangitis (sclerosing, AIDS), intermittent/partial obstruction. 5. False positive CBD dilatation: Prior obstruction, ⫾ cholecystectomy, elderly patients, intestinal hypomotility. B. How to scan the CBD (1) Distal duct: Position patient RPO and initially scan transversely at level of uncinate. Alternative position is to scan with patient erect. (2) Proximal duct: Position patient LPO and initially scan sagittally. C. Level of obstruction (1) Pancreatic ⫽ 90%: choledocholithiasis, strictures, pancreatic cancer. (2) Supra- pancreatic ⫽ 5%: metastatic disease, primary biliary cancer. (3) Porta-hepatis ⫽ 5%: cholangiocarcinoma (Klatskin tumor), neoplasm, surgical stricture, Mirizzi syndrome (seen with calculus in GB neck/cystic duct; low insertion of cystic duct, normal size distal duct). D. Echoes in or near the common bile duct: Etiology ⫽ calculi, hepatic artery, reverberations, gas, surgical clips, cystic duct, pancreatic calcifications, sludge, blood, neoplasm. APPLICATION of US re BILE DUCTS A. Primary Role: (1) Screen for biliary obstruction. a. Sensitivity ⫽ 68% to 99%. b. specificity ⫽ 75% to 100%. B. Secondary Role: (1) Determine level/cause for obstruction. a. Level ⫽ up to 92% of cases. b. Cause ⫽ up to 71% of cases. 1025 Cystic lesions of the pancreas: Ultrasound differential diagnosis Greiner L, University of Witten, Germany Ultrasonography (US) renders a direct access to pancreatic morphology. Resolution capabilities of US are not achieved by the secondary imaging modalities (computed tomography CT and magnetic resonance MR), and the realtime information in US examination (e.g., elasticity, perfusion, neighbourhood motility) are not available by other modalities either. These unique features of US hold true as well in cystic