Journal De Radiologie最新文献

Purpose

To determine the value of US screening for detection of developmental dysplasia (DDH) in girls in the setting of a multi-disciplinary program in pediatric orthopedics.

Materials and methods

Systematic US evaluation of the hips using the Couture technique was performed at 1 month in all girls with normal physical examination at birth over a 1 year period. The examinations were classified as normal or abnormal (DDH [acetabular depth > 6 ], asymmetrical pelvis, borderline hips). Results were correlated with risk factors and clinical outcome. Girls with abnormal hips were immediately treated.

Results

One thousand one hundred and sixty-six girls were screened. A total of 4.7% of ultrasound examinations were abnormal. The rate of pathological hip was 3.7% in the absence of risk factors and 8.9% in the presence of risk factors. A total of 63.6% of girls with abnormal ultrasound examination had no risk factor. Two risk factors were correlated to the presence of DDH: family history (RR = 3.12) and clinical abnormalities (RR = 2.55). The rate of pathological hip that were referred for treatment was 3.1%. All hips were normal at 5 months.

Conclusion

Ultrasound screening evaluation of the hip in girls at 1 month, in the setting of a multi-disciplinary program in pediatric orthepedics clinic, is feasible. A total of 74 abnormal hips undetected at the initial clinical evaluation in girls without risk factor were detected and treated. Systematic screening of girls for DDH must be further assessed to better determine its impact on the incidence of delayed diagnosis of DDH.

Radiofrequency ablation is an image-guided technique of percutaneous tumor destruction using high frequency alternating current. Accuracy in needle placement and the selection of the imaging modality are key elements of the success of the procedure. The volume of ablation with a single needle insertion is limited to about 40 mm and the technique is most successful for tumors less than 3 cm in diameter with rapid decrease in efficacy for larger tumors. Tumors further away from large vessels are also more efficiently treated with this technique since heat loss from flowing blood in nearby vessels larger than 3 mm causes a four-fold increase in treatment failure. Under the best of circumstances (tumor less than 25 mm, away from vessels), RF ablation and surgical tumorectomy have respective failure rates of 6% and 7,3%. RF ablation of an isolated liver metastasis less than 4 cm in diameter results in survival rates at 1, 3 and 5 years of 97%, 84% and 40% respectively. In the liver, follow-up imaging is performed to detect residual tumor characterized by early enhancement. Thin peripheral enhancement (less than 1 mm) of the necrotic area and well-defined triangular shaped regions of enhancement are not signs of tumor recurrence but indicate the presence of inflammation or arterial to portal venous fistula. In the lung, an area of ground glass attenuation four times larger than the initial tumor is a predictive factor of success. PET-CT is the best imaging modality for follow-up of lung lesions following RF ablation.

A recent survey has compiled an inventory as complete as possible of the activities of interventional radiology in oncology in France. This overview has focused on identifying all invasive medical procedures whose aim was diagnosis and/or treatment of a tumor, which was carried out under guidance and under the control of an imaging means (RX, ultrasound, CT, MRI). If the biopsies represent more than half of the actions carried out under controlled imaging, recent years have seen the development of increasingly powerful therapeutic techniques.

Since the introduction of radiofrequency tumor ablation of liver tumors in the late 1990s, local destructive therapies have been applied to lung, renal and bone lesions. In addition, new techniques have been introduced to compensate for the limitations of radiofrequency ablation, namely the reduced rate of complete ablation for tumors larger than 3 cm and tumors near vessels larger than 3 mm. Microwave ablation is currently evolving rapidly. While it is a technique based on thermal ablation similar to radiofrequency ablation, there are significant differences between both techniques. Electroporation, of interest because of the non-thermal nature of the ablation process, also is under evaluation.

Bone metastases are frequently symptomatic. The pain is specific due to its pathophysiology, characteristics and treatment. Conventional antalgic pain management may be insufficient and management should be multifacetted, global and multidisciplinary. Interventional radiology procedures widen the range of possible antalgic therapies. Their role in the management of patients should be defined by a multidisciplinary team on a case-by-case review, based on the patient's symptoms and fracture risk. Additional scientific validation of the effectiveness of such therapies is needed. Recommendations on the role of interventional radiology procedures in the management of patients with symptomatic bone metastases are needed to standardize the different practices and increase the role of interventional radiology in the management of symptomatic bone metastases at the national level. Implementation of the cancer 2009–2012 project could facilitate the availability of these therapies to patients with cancer pain.

Interventional oncology in private practice requires expert training and can be performed in a stand-alone facility for type 1 procedures in a hospital setting for type 2 and 3 procedures where subspecialized radiologists, state-of-the-art equipment, and postprocedure hospital monitoring are available. A multidisciplinary effort with oncologists, internal medicine physicians and anesthesiologists is necessary. The practice of interventional oncology requires around the clock availability, meticulous and established protocols and procedures and a financial investment. On the other hand, it is professionally gratifying because of constant technical advances and the impact on patients.

Percutaneous ablation of renal tumors, including radiofrequency ablation and cryoablation, are increasingly being used for small tumors as an alternative to surgery for poor surgical candidates. Compared to radiofrequency ablation, cryoablation has several advantages: improved volume control and preservation of adjacent structures due to the excellent depiction of the ice ball on CT and MRI; better protection of the collecting system for central tumor with reduced risk of postprocedural urinary fistula. The main pitfall of cryoablation is the higher cost. Therefore, cryoablation should be reserved for the treatment of complex tumors. In this article, we will review the different steps of percutaneous renal tumor ablation procedures including patient selection, technical considerations, and follow-up imaging.

Colorectal carcinoma is a major public health concern with its yearly mondial incidence of about one million cases and yearly mortality of 500,000 cases. The liver is the organ most frequently affected by metastases with a frequency of 40 to 60% (contemporaneous in 25% of cases). While surgical resection is the only curative therapy, many patients are not such candidates due to the infiltrative nature of the liver metastases. Systemic chemotherapy and biotherapy regimens are the conventional treatment options for patients with multiple liver metastases. Under such circumstances, intra-arterial therapy may play a major role. We will review the main types of endovascular therapies for liver metastases from colorectal carcinoma including indications, results and potential complications.

Ultrasound-guidance is frequently used at the time of biopsy. Its numerous advantages include: lack of ionizing radiation, real-time visualization of the needle tip, flexibility to approach lesions from variable and complex angles, wide availability of ultrasound units. A certain level of experience is nonetheless required to ensure adequate and successful lesion targeting. New software are available to assist the operators. “Electromagnetic navigation” can assist in locating the needle tip and predicting its trajectory. Image fusion with previous cross-sectional imaging studies can assist in detecting lesions that are less conspicuous on routine ultrasound images.