[Ultrasound of the Achilles tendon after percutaneous repair]. / Echographie des ruptures du tendon calcanéen après ténorraphie percutanée.

PURPOSE: To evaluate clinical and ultrasound (US) results following percutaneous repair of the Achilles tendon. MATERIALS AND METHODS: Thirty-four patients underwent percutaneous Achilles tendon repair between 2004 and 2006. Seventeen patients (11 males and 6 females aged 30 to 59 years) underwent clinical and US follow-up at a mean of 15 months. US evaluation included assessment of the bilateral Achilles tendons with recording of maximum tendon diameter, echotexture, and presence of intratendonous neovascularization on power Doppler US. RESULTS: On clinical evaluation, all patients were satisfied with the outcome and able to resume their normal level of activity. On US evaluation, there was no tendon discontinuity, and all tendons showed hypoechoic thickening with mean maximal diameter of 13 mm. Focal changes in echotexture were noted in 11 patients, hypoechoic in 5 cases and echogenic in 6 cases. A normal fibrillar echotexture was noted in 5 cases, at more than on eyear after surgery. Intratendonous neovascularization was present in 10 cases, mild in 6 cases, moderate in 2 cases and marked in 2 cases. The degree of neovascularization decreased with increasing postsurgical time. CONCLUSION: Postsurgical Achilles tendons were characterized on US by hypoechoic thickening and loss of normal fibrillar echotexture. The presence of intratendonous neovascularization probably corresponds to postsurgical scarring that decreases over time.

[What is the thickness of the normal appendix on MDCT?]. / Quelle est l'épaisseur de l'appendice normal au scanner multibarrette?

OBJECTIVE: To determine the wall thickness and external diameter values of the normal appendix on multidetector computed tomography (MDCT). Materials and methods. A senior radiologist with no knowledge of the patient's surgical history prospectively examined the abdominal-pelvic CT scans of 57 consecutive adult patients with no suspicion for appendicitis. Most of the patients (50/57) received an intravenous iodinated contrast material injection, but none had gastrointestinal studies. All slices (1 and 5 mm) and multiplanar reconstructions were analyzed on a treatment console. The external diameter of the appendix, the thickness of the two appendicular walls, and the presence or absence of intraluminal gas were noted. RESULTS: The appendix was visualized in 82% of the cases (47/57). The mean external diameter was 6.7 mm+/-1.2 (range, 5.0-11.0 mm). The mean thickness of the two walls was 4.8 mm+/-1.0 (range, 2.6-6.4 mm). Intraluminal air was visualized in 87% of cases (41/47). CONCLUSION: Contrary to external diameter, the normal thickness of the appendix's two walls does not go beyond the threshold of 6 mm and therefore seems to be a reliable measurement for identifying a normal appendix using MDCT.

[Focal liver lesions in oncology]. / Lésions hépatiques en cancérologie générale.

In order to improve management of oncologic patients, a standardized 5-step approach should be considered: detection, characterization, locoregional and systemic staging, and post treatment follow up. The use of imaging techniques will be adapted to the clinical question at hand during multi-disciplinary review of cases. The role of the radiologist is to review the indications for each imaging modality and incorporate the results in the clinical context.

[Is appendicolith a reliable sign for acute appendicitis at MDCT?]. / Le stercolithe est-il un signe fiable d'appendicite?

PURPOSE: To determine the frequency of detection of appendicoliths on normal appendix at multidetector row computed tomography (MDCT) with multiplanar reconstructions (MPR). MATERIALS AND METHODS: A senior radiologist, blinded to patient's surgical history, prospectively and independently reviewed abdominopelvic MDCT scans in 57 consecutive adult patients without symptoms suggesting appendicitis. Most patients had IV iodine injection, but no oral contrast. Thick (5 mm) and thin (1 mm) slices were analyzed on a workstation. MPR were available. Localization of the appendix, overall diameter, intraluminal gas and appendicolith were recorded. RESULTS: The appendix was visualized in 47/57 (82%). An appendicolith was found in 13%. Intraluminal gas was identified in 87%. The localization was retrocaecal (47%), mediocaecal (21%) or pelvic (32%). The mean overall diameter of the normal appendix was 6.7 mm +/- 1.2 (SD). CONCLUSION: Appendicolith was found in a significant number of normal patients at MDCT and don't represent a specific sign for appendicitis.

Ultrasound contrast agents: properties, principles of action, tolerance, and artifacts.

The concept of contrast imaging was introduced to ultrasound almost 30 years ago. The development of ultrasound contrast agents (USCAs), initially slowed by technical limitations, has become more dynamic during the past decade. The ideal USCA should be non-toxic, injectable intravenously, capable of crossing the pulmonary capillary bed after a peripheral injection, and stable enough to achieve enhancement for the duration of the examination. While satisfying cost-benefit requirements, it should provide not only Doppler but also gray-scale enhancement. Already, Doppler examinations are improved by using USCAs when studying deep and small vessels, vessels with low or slow flow, or vessels with a non-optimal insonation angle. Ultrasound contrast agents also enhance detection of flow within abnormal vessels, including tumor vascularization and stenotic vessels, and provide better delineation of ischemic areas. Research is focusing on the development of specific contrast imaging sequences that allow detection of tissue enhancement similar to that obtained with CT or MRI. These sequences take advantage of the nonlinear behavior of the microbubbles within the ultrasound field, bringing real-time perfusion imaging for liver, kidney, and the myocardium into reach. New objectives include targeted agents that could further widen USCA applications to specific delivery of active drugs such as anticoagulants or cytotoxic compounds. The combination of new generations of USCAs and new ultrasound image sequences appears to be very promising and currently represents a significant part of ultrasound research.