ultrasound-guided high-intensity focused ultrasound treatment in pa-tients with advanced pancreatic cancer, ultrasound guided treatment oftendinitis of the shoulder, ultrasound guidance for central venouscatheter insertion, percutaneous thermal ablation for recurrent carci-noma, foreign bony retrieval and intravascular ultrasonography forTIPS. The authors will describe some fundamentals of ultrasoundguided therapy, which are applicable in many of these treatments.Needle tip visualization is a key factor and may be improved bypractices such as careful selection of needle angle versus beam angle,creation of an acoustic window using saline injection techniques,trochar pumping to create microbubble reflections and probe rockingtechniques. In line and transverse identification are both utilised tooptimise imaging of needles and other devices. Minification of trans-ducer design allows intravascular and intraductal ultrasound guidancefor advanced therapies. Injection of fluid and air may both be useful toconfirm correct anatomical location. Colour Doppler may be used totrack injection position and flow, as well as monitor success of proce-dures such as pseudo-aneurysm thrombosis. Tissue elasticity may besimply evaluated using an external vibrating source with power Dopp-ler to highlight thyroid and breast lesions for biopsy, a dramaticimprovement on the more widely used vocal fremitus technique. Op-timum positioning of the ultrasound equipment, patient, operator, probeand sonographer are a key factor in all interventional procedures.

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Interventional musculoskeletal ultrasoundCardinal E, Centre Hospitalier Universitaire De Montreal, Canada

The learning objective is to be familiar with the indications andtechnical aspects of musculoskeletal procedures that can be performedunder ultrasound-guidance. Ultrasound (US) is used to investigate anumber of musculoskeletal pathologies. Because of its real-time capa-bilities, US is also useful to guide numerous musculoskeletal proce-dures. The purpose of this presentation is to describe a number ofUS-guided musculoskeletal procedures. Technical considerations willbe reviewed. Procedures such as aspiration and drainage of cysts andhematomas and abscesses arthrocenthesis, infiltrations of bursae, ten-dons sheath and fascia, biopsy of soft tissues, synovium, bone andtreatment of shoulder calcified tendinitis will be described.

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Ultrasound guided procedures: Techniques and practical tipsHan JK, Seoul National University Hospital, Korea

Ultrasound guiding technique is a basic skill to various interventionalprocedures. In the past, fine needle aspiration cytology and needleaspiration of fluid collection were the majority. However, with theimprovement of techniques and devices, core biopsy, US guided cath-eter drainage of various fluid collections, percutaneous ethanol injec-tion therapy for malignant tumor were tried. Recently, newer methodsof tumor ablation such as radiofrequency, microwave and interstitiallaser were introduced. Ultrasound has advantage of real time imaging,multiplanar imaging and portability. Also, it is widely available, eco-nomic and free of radiation hazard. However, US has disadvantage ofinferior image resolution compared to CT, limited penetration behindthe bowel. This lecture will cover (1) basic principle of US guidingtechnique, (2) tips for targeting small lesions, (3) tips to avoid com-plications and (4) tips to obtain good sample in biopsy or aspirationcytology. Also, this lecture will briefly cover (5) the impact of recentultrasound technology such as real time 3D imaging in the US guidedprocedures. The most important thing to remember in US guiding is tokeep the alignment of needle and transducer. To keep the alignment,either free hand technique or using specially designed guiding devicesis used. Finding the needle tip and whole length of the needle is crucial

part of the procedure. To improve the visibility of the needle tip, thesimplest method is removing the stylet. It introduces air into the needlelumen and increase the echogenicity. Also, little to and fro movementhelps to find the needle in echogenic background. Some manufacturesproduce specially treated needle with increased echogenicity. To avoidcomplication, good understanding of the anatomy and choosing thesafest route of access is very important. To get a good sample duringaspiration or biopsy, the operator must know the characteristics of thetarget lesion and how the sample is processed by the pathologist. Realtime 3D imaging (4D ultrasound) is a promising tool in US guidedprocedure. It helps to locate the needle located out of the scan plane andgives clear 3D orientation of needle and target. Currently, bulky size ofthe transducer is the main limitation in applying this technique toroutine daily procedure.

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Thermoablation of hydatid cystDrinkovic I, Croatian Senologic Society, Croatia

The Hydatid cyst is a very frequent disease in Mediterranean countries.Every year in Croatia, some 20 to 30 patients are diagnosed with ahydatid cyst. In 1990 to 2006 there were 340 patients with echinococ-cosis hospitalized in the Hospital for Infective Diseases, 86% of whichappeared as hepatic cysts. The hydatid cyst can be treated by chemo-therapy with only a 30% success rate, or by surgery, which can causemajor liver damage, while surgery is either not an option or ends upbeing unsuccessful in a great many other cases. Percutaneous treatmentcan be guided by ultrasound, and we use two methods—alcohol scle-rosation or radio frequency thermoablation. The criteria for eithermethod depend on the location and/or complexity of the cyst andwhether it is multiple or not. Prior to an ultrasound guided procedure,the patient should take albendazole for 28 d in three cycles, while theprocedure is performed a few days after chemotherapy has ended.Alchohol sclerosation is performed in smaller cysts. After a puncturedcyst is evacuated and refilled with 95% sterile alcohol, which remainsin the cyst for 20 min before reevacuation. Complicated or larger cystsand even recurrent cysts, are treated by HITT therapy, using a hyper-osmolarity solution and increasing temperatures by up to 90 to 100°C.The duration of treatment is approximately 30 min and after thehypertonic solution has been evacuated. After thermoablation therapy,all scolices in the evacuated hyperosmolar solution are destroyed. Inour materials there are more than 150 alchohol and radio frequentablation treated cysts with a 90% success rate in alcohol sclerosationtreatment. Moreover a near 98% success rate was noted in HITTtherapy, even in complicated cysts.

CONGENITAL ANOMALY

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Antenatal prediction of severity of fetal pulmonary hypoplasia incongenital diaphragmatic herniaKalache K, Princess Anne Hospital University of Southampton,United Kingdom of Great Britain and Northern Ireland

Several studies have attempted to assess pulmonary hypoplasia infetuses with congenital diaphragmatic hernia (CDH) in order to predictlung function at birth. The traditional approach consisted to establishultrasonographic markers that are affected by severe pulmonary hyp-oplasia either by measuring the fetal lungs using two-dimensionalultrasonography or three-dimensional ultrasonography. Others haveconcentrated on Doppler studies of indirect markers of severe lungunderdevelopment such as vascular hypoplasia and reduced fetalbreathing related lung fluid flow. Herniated organs in CDH compress

P38 Ultrasound in Medicine and Biology Volume 32, Number 5S, 2006