No abstract

Contrary to common perception, the advent of third- and fourth-generation scanners has lead to a significant increase in radiation dose to the patient per computed tomography (CT) head scan. With that in mind, a pilot study was designed with the objective of assessing the effectiveness of a dental-style protective bib in reducing the dose to the radiosensitive organs of the neck and thorax. Radiation doses over the thyroid gland and breast were measured with thermoluminenscent dosemeters and an ionization chamber respectively in 110 patients undergoing routine head scans. Half the patients wore the protective bib and collar. With lead protection, the thyroid measurements were reduced by an average of 45 % and the breast measurements by an average of 76 %. Similar results were seen in phantom measurements.

The diagnosis of primary aldosteronism, the most common form of secondary hypertension, is based on clinical and biochemical features. Although radiology plays no role in the initial diagnosis, it has an important role in differentiating between the two main causes of primary aldosteronism: aldosterone-producing adenoma (APA) and bilateral adrenal hyperplasia (BAH). This distinction is important because APAs are generally managed surgically and BAH medically. Adrenal venous sampling is considered the standard of reference for determining the cause of primary aldosteronism but is technically demanding, operator dependent, costly, and time consuming, with a low but significant complication rate. Other imaging modalities, including computed tomography, magnetic resonance imaging, and adrenal scintigraphy, have also been used to determine the cause of primary aldosteronism. Cross-sectional imaging has traditionally focused on establishing the diagnosis of an APA, with that of BAH being one of exclusion. A high specificity for detecting an APA is desirable, since it will avert unnecessary surgery in patients with BAH. However, an overreliance on cross-sectional imaging can lead to the incorrect treatment of affected patients, mainly due to the wide variation in the reported diagnostic performance of these modalities. A combination of modalities is usually required to confidently determine the cause of primary aldosteronism. The quest for optimal radiologic management of primary aldosteronism continues just over a half century since this disease entity was first described.

Fifty-two knees were examined using real-time highdefinition ultrasonography with a 7.5MHz probe. The extra-articular structures were easily visualized and diagnosis of patellar tendon lesions and Baker's cysts formulated. While the meniscal cartilages were shown as a homogeneous triangular structure between the femoral condyle and the tibial plateau, no lesions were detected. Deeper intra-articular structures, such as the cruciate ligaments, were not shown by the scan, thus their evaluation was not possible. Given its low cost, wide availability, non-invasiveness and patients' acceptability of the technique, ultrasonography may play an important role in the diagnosis of soft tissue lesions in and around the knee joint.

No abstract