The role of ultrasound in breast imaging

Sonography has become an important tool for evaluating breast abnormalities, including inflammatory processes, hematomas, ductal ectasia, cysts and solid lesions. This article describes protocols for ultrasound imaging of the breast and the sonographic appearance of common breast conditions, with particular attention to differentiating benign from malignant lesions. Ultrasound's role in interventional breast procedures and radiation therapy planning also are discussed.     

CT of pregnancy-related complications

During pregnancy, the risk of radiation exposure to the fetus is increased so that more than the usual benefit is necessary to justify computed tomography (CT; or other radiation exposure) than in non-pregnant patients. In the setting of a life-threatening illness, CT may be indicated to assess for potentially fatal complications such as hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome. After delivery, patients rarely develop serious problems requiring radiologic evaluation. When indicated, however, CT may be invaluable in making the diagnosis or determining the severity of peri- and post-partum complications, including uterine perforation, hemorrhage, endometritis, thrombophlebitis, and abscess formation. At times, CT may be the first to uncover conditions, such as post-partum cardiomyopathy, and heart failure, which are usually diagnosed by other modalities but may explain the symptoms for which the study was ordered. In some centers, CT pulmonary angiography represents the standard of care to diagnose pulmonary thromboembolism. In this article, we illustrate the spectrum of peri-partum and post-partum complications on CT to familiarize the radiologist with the CT features of these potentially life-threatening pregnancy-related complications.     

The role of transvaginal ultrasound in a referral military hospital

In an attempt to overcome some of the difficulties encountered with transabdominal ultrasonography we report on 55 patients who underwent 88 transvaginally directed sonograms. In 24 patients in whom a diagnosis of an early intrauterine pregnancy was made, the mean crow-rump length (CRL) was 10.7 mm (range, 3 to 27). In six patients (25%) the CRL was 5 mm or less. These data suggest that the use of transvaginally directed sonography may permit an earlier diagnosis of pregnancy than the abdominal approach does. This earlier diagnosis should allow the exclusion of ectopic pregnancy in many of the patients at risk for this disorder.     

The role of ultrasound scanning in management after liver transplantation

A total of 368 ultrasound scans in 72 patients following liver transplantation have been reviewed. Thirty-seven intra-abdominal fluid collections were identified. Twenty-four resolved spontaneously and 13 required aspiration under ultrasound control. Dilated bile ducts were seen in 22 patients, 11 of whom required further intervention. The main indications for intervention post-transplantation were increasing or late onset (after 3 months) duct dilatation. Recurrent or persistent fluid collections particularly in the right subhepatic space also indicate further investigation. Twelve ultrasound-guided liver biopsies were performed to detect rejection or tumour recurrence. Eight cases of portal vein anastomotic narrowing and three abnormalities of the inferior vena cava were also detected.     

彩色多普勒超声对颈动脉体瘤的诊断价值

颈动脉体瘤是起源于颈动脉副神经节细胞的化学感受器肿瘤,部分有恶性潜能,因其症状不明显,常易被误诊为肿大淋巴结,以往确诊依赖颈动脉血管造影。本文回顾性分析10例颈动脉体瘤超声表现,旨在通过分析与总结二维声像和彩色多普勒超声的图像特点,以提高对颈动脉体瘤的认识。     

The role of ultrasound in the detection of non-radiopaque foreign bodies

Fifty consecutive ultrasound examinations performed for suspected non-radiopaque foreign bodies in extremities were reviewed to establish the value of this procedure. Ultrasound detected 21 of 22 foreign bodies found at operation. There were three false positive examinations. The sensitivity was 95.4%, the specificity 89.2%, the positive predictive value 87.5% and the negative predictive value was 96.2%. This study demonstrates that ultrasound is a reliable method for detecting non-radiopaque foreign bodies and makes a significant contribution to patient management.     

The role of ultrasound and magnetic resonance in local drug delivery

Local drug delivery has recently attracted much attention since it represents a strategy to increase the drug concentration at the target location and decrease systemic toxicity effects. Ultrasound can be used in different ways to trigger regional drug delivery. It can cause the local drug release from a carrier vehicle and the local increase of cell membrane permeability either by a mechanical action or by a temperature increase. Ultrasound contrast agents may enhance these effects by means of cavitation. Ultrasound can be focused deep inside the body into a small region with dimensions on the order of 1 mm. Several types of drug microcarriers have been proposed, from nano- to micrometer sized particles. The objective of real-time imaging of local drug delivery is to assure that the delivery takes place in the target region, that the drug concentration and the resulting physiological reaction are sufficient, and to intervene if necessary. Ultrasound and nuclear imaging techniques play an important role. MRI is rather insensitive but allows precise targeting of (focused) ultrasound, can provide real-time temperature maps, and gives access to a variety of imaging biomarkers that may be used to assess drug action. Examples from recent articles illustrate the potential of the principles of ultrasound-triggered local drug delivery.     

The role of ultrasound in the management of ovarian masses in children

A retrospective study of 64 girls with ovarian cysts and tumours, diagnosed by ultrasound over 4 years, was undertaken. Most ovarian cysts were benign and conservative management with serial ultrasound scans helped to avoid unnecessary surgery. The incidence of surgery decreased from 18 operations in the first 2 years of the study to 10 operations in the second 2 years. All children for whom surgery is considered should have a pre-operative scan to determine whether the cyst has resolved. Immediate surgery is indicated in children who have a palpable mass, a solid mass, a mass associated with calcification, or a mass associated with persistent pyrexia. Appendix abscesses may mimic ovarian masses and can be correctly diagnosed by ultrasound.     

The role of transvaginal ultrasound in the assessment of the female pelvis

Transabdominal ultrasound of the female pelvis has been compared with transvaginal ultrasound, using a 7.5 MHz transducer, in 80 women. Transvaginal ultrasound required less patient time and was preferred in 56% of patients. Image quality was superior in 72% of cases, and visualisation of the pelvic organs was equivalent with each technique. Transabdominal ultrasound gives a more global view of the pelvis, and is of more value in assessing large pelvic masses. Transvaginal ultrasound is of more value in assessing early pregnancy, ectopic pregnancy, ovarian abnormalities, and for visualising the ovaries following hysterectomy.     

The role of ultrasound in the management and diagnosis of infectious mononucleosis

Currently, infectious mononucleosis (IM) is a clinically diagnosed condition. According to the American Family Physician criteria for IM, splenomegaly is the key factor that distinguishes IM from other causes of sore throat. Though heterophile antibody tests are often ordered to confirm diagnosis of IM, this test has a high false-negative rate early in the course of the disease. This case report provides an example of how the use of ultrasound to diagnose splenomegaly and subsequently mononucleosis increases diagnostic accuracy.