Acta radiologica: diagnosis最新文献

A case of an adult patient with ileocolic intussusception secondary to a lymphoma of the terminal ileum is reported. On the computed tomograms, a target mass, with the outer rim representing the annular tumour of the terminal ileum and the eccentric rim of low attenuation representing the mesentery, is described. Ultrasound patterns are those of parallel hypoechoic areas separated by hyperechoic stripes seen on longitudinal sections, and of a rounded mass of low echogenicity, exhibiting two hyperechoic concentric ring-like areas within it, on transverse scans. The appearances of the barium examinations are also described. The English literature is reviewed.

A case of torsion of the wandering spleen in an infant is presented. The value and limitations of various imaging modalities in making a correct preoperative diagnosis are discussed and a brief review of the literature is given.

An initial manual bolus injection of contrast medium to an amount of 15 g iodine immediately followed by a manual infusion of 25 to 35 g iodine during 3 to 5 minutes will provide proper enhancement of vascular structures (110-150 HU) at incremental body computed tomography during that time and for some minutes after the end of the infusion. This technique applied in more than 1,000 examinations proved it to be reliable, simple and fast. A computed tomograph allowing 3 scans per minute permits an adequate and even level of vascular enhancement of the entire neck, mediastinum, abdomen or pelvis when continuous or more sparse slices of about 10 mm thickness are used. When the images are reconstructed without delay and presented on a monitor in the scanning suite, it is possible to individually optimize the rate of infusion and thereby also minimize the amount of contrast medium. A prerequisite for a proper vascular enhancement is a high rate of infusion initially.

From a series of balloon dilatations of alimentary tract strictures 11 patients with different types of gastric and oesophagogastric anastomotic stenoses are reported. The dilatation of gastric outflow tract obstructions was highly effective in the treatment of retention. In 7 out of 8 cases with gastric outflow stenosis surgery could be entirely avoided and replaced by balloon dilatation. The importance of eliminating retention in the healing of gastric ulcer is discussed. Fistulation in oesophagogastric anastomoses due to stenosis of the outflow portion was successfully treated. The importance of achieving a free outflow tract in order to prevent insufficiency of the anastomosis and formation of a fistula is stressed.

A review of 6,225 hysterosalpingographies disclosed four cases of inadvertently performed examinations during early pregnancy. These radiologic misadventures were in three cases performed because of oligomenorrhoea and in one case because of a misjudged decidual bleeding. The radiologic findings and the outcome of these pregnancies are presented. Precautions to avoid this radiographic error are discussed.

Two patients with primary hyperparathyroidism were examined before parathyroid surgery with magnetic resonance imaging at 0.35 tesla in order to analyse optimal methods of visualization. Two large parathyroid glands in the neck had long transverse relaxation times which rendered them clearly visible in T2-weighted images as structures of a signal intensity higher than that of the surrounding. Large parathyroid lesions may thus be easily detected by magnetic resonance imaging provided proper examination parameters are employed.

The continuous technical development of cranial CT and the accumulation of clinical experience with this method, have resulted in the use of an increasing number of scan protocols for different clinical situations. An investigation was undertaken to find out how this change has influenced the dose delivered to the patient. The eye lens dose was measured at CT examinations in 245 patients, with appropriate scan protocols, and also at corresponding examinations in an anthropomorphic head phantom. One CT scanner of early (EMI CT 1010) and one of modern design (Siemens Somatom DR2) were investigated. The range of the eye lens dose was wide, namely 4 to 206 mGy for EMI CT 1010 and 6 to 124 mGy for Somatom DR2. In patient groups with comparable scan protocols the mean eye lens dose was higher with the Somatom DR2, mostly on account of a different spatial distribution of the dose in the scan plane. The dose varied less with this scanner, however, mainly because of the possibilities for more accurate positioning.

Retinoblastoma is the most common primary malignant intraocular tumor in children. The clinical features are leucocoria and/or strabismus. The ophthalmic diagnosis is straight forward in clear eye media with a white gray mass in the fundus. With opaque ocular media, other diagnostic procedures such as CT and ultrasonography are important. In the present study the results of CT examinations of 23 patients with histologically proven retinoblastomas are presented. The mean age of the patients was two years. The characteristic CT finding is a partly calcified intravitreous mass lesion mostly confined within the eyeball. Two cases showed retrobulbar extension and two intracranial tumor extension. No metastasis was found in the brain, liver, spleen, long bones, chest or skull. The radiologic screening procedures for retinoblastoma metastasis are discussed. In patients suspected to have a retinoblastoma, it is recommended to perform CT of the orbits and brain in order to detect the tumor and its possible retrobulbar and intracranial extension.

Following fractures of the distal radius, a relatively high incidence of complications is caused by malalignment in the distal radio-ulnar (DRU) joint; recent anatomic and clinical investigations have shown congruity of that joint to be of significant importance for restoring the function of the wrist. The radius forms a moderately arched bone, which moves around the ulna in pronation and supination. Biomechanically, the ulna may be regarded as the pillar around which the radius moves. In an anatomic investigation of 5 arm specimens, we have shown that the maximum cartilage contact in the DRU joint between the ulnar head and the distal radius occurs in the neutral rotation position. A proposed routine examination method of the wrist and forearm includes a true antero-posterior and a lateral projection of the radius and the ulna, performed with the forearm and wrist in a neutral rotation, a neutral wrist deviation and with the elbow angled 90 degrees. Such an examination implies a standardized and reproducible method. In a radioanatomic investigation, a series of 50 healthy wrists and forearms were examined. A simple measuring technique is presented, applicable to the DRU joint and wrist favouring the ulna as the bone through which a reproducible long axis of the forearm/wrist may be drawn. It is suggested that the length of the radius should be judged relative to the ulna. Ulnar head inclination and radio-ulnar angle are new concepts, being major characteristics of the DRU joint. These angles of the right and left wrist were equal and no difference was found between the sexes. Minor alterations of the distal radius may be revealed when estimating these angles.

Three modern low osmolar contrast media (Iopamiro, Omnipaque and Hexabrix) were injected intravenously in 150 patients. They were all effective for urography in a concentration iso-osmolar to blood and with a dose of 90 mg I/kg body weight in patients with normal renal function. In patients with decreased renal function, this low dose is not sufficient and should be doubled. No significant diagnostic differences between the three media were found. The subjective and objective adverse effects were minimal and transient.