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Thermal ablation by physical agents is widely used in clinical settings, but it generally results in a small coagulated volume. Here, we report that a technologically advanced high intensity focused ultrasound transducer can significantly enlarge the coagulated volume over short periods of time. Eight ultrasound emitters were created by sectioning a single toric piezocomposite transducer. A single thermal lesion is created when the eight emitters perform alternative and consecutive 5 s ultrasound exposures. This paper presents in vivo evidence that the coagulated volume obtained from a 40 s total exposure in the liver was 8.6±4.8 cm3. [ABSTRACT FROM AUTHOR]

Objective: To demonstrate in a porcine model that high-intensity focused ultrasound (HIFU) with toroid-shaped emitters may have a role in treating unresectable colorectal liver metastases., Summary Background Data: Surgical resection is the only curative option for colorectal hepatic metastases. Only 20% of patients are suitable for surgery. Many ablative techniques have been assessed but several limitations have been documented: traumatic puncture of the parenchyma, limited size of lesions, and inability to monitor the treatment in real time., Methods: A HIFU device with 256 toroid-shaped emitters and integrated ultrasound imaging probe was used. Single lesions, induced in 40 seconds, and juxtaposition of 6 single lesions were created under ultrasound guidance on 13 pigs. The lesions were studied on sonograms, macroscopically and microscopically up to 30 days after the treatment., Results: Ninety percent of the HIFU lesions were immediately hypoechoic on ultrasound imaging. The average coagulated volume obtained from a 40 seconds total exposure in the liver was 7.0 +/- 2.5 cm (1.5-20.0), average diameter: 19.5 +/- 3.8 mm (10.0-29.0). Using the real-time visualization of the treated region, single lesions were easily juxtaposed to produce larger lesions up to 6 cm in diameter without any major complication., Conclusions: This toroid HIFU device allows short treatment times, noninvasiveness regarding the liver and real time ultrasound guidance. It seems to be simpler and more reliable to use than current ablative methods. Additionally, lesions through large vessels (up to 5 mm) being feasible, treatment of some juxta-vascular metastases should be possible.

A new geometry of High Intensity Focused Ultrasound (HIFU) transducer is described to enlarge the coagulated volume and decrease treatments time. Eight transducer elements and their quarter-wave plate were diced out of a single toric piezocomposite element. Each transducer operates at a frequency of 3 MHz. The focal zone is conic and located at 70 mm from the transducer. A 7.5 MHz ultrasound imaging probe is placed in the centre of the device for guiding the treatment. Optimal exposure parameters were determined from numerical simulations. This new geometry allows achieving a thermal ablation of 7.5 cm3 when each of the eight transducers has performed a 5-s ultrasound exposure alternatively and consecutively. In vivo trials have been performed on five pigs to demonstrate this new principle. 33 elementary lesions have been performed. All lesions were reproducible and homogeneous. The average diameter of an elementary lesion obtained in 40 seconds was 19.5 +/- 3.8 mm (min 10 - max 29 mm). The coagulated volume obtained in 40 seconds was on average 9.1 +/- 4.6 cm3 (min 1.5 - max 17.6 cm3).

Objectives: To determine the prevalence of anal incontinence in a population of 291 women with pelvic organ prolapse and evaluate the results of pelvic viscerogram in this situation., Materials and Methods: Each patient answered a standardized questionnaire on medical, obstetric and surgical past histories and answers were logged in a database. The viscerograms were performed by a single specialized radiologist., Results: All patients but one were parous. The prevalence of anal incontinence was 26.1%. Stress urinary incontinence and urge urinary incontinence were significantly associated with anal incontinence. No obstetric or surgical risk factor for anal incontinence was demonstrated. Viscerography demonstrated rectoceles (n=86, 29.1%), enteroceles (n=77, 26.5%), cystoceles (n=174, 59.8%), and intra-anal rectal prolapse (n=106, 36.4%). A significant association was found between intra-anal rectal prolapse and anal incontinence., Conclusion: Anal incontinence is frequent in patients with pelvic organ prolapse, even more so in the presence of urinary incontinence, and should be investigated by pelvic viscerography. Pelvic floor dysfunction is frequently associated with enteroceles, rectoceles and rectal prolapse. Pelvic viscerograms should be systematically performed in the diagnostic work-up in patients with pelvic organ prolapse when surgical treatment is considered.