Magnetic resonance imaging , with its superior soft-tissue differentiation, is the study of choice for most diseases of the spine because of its ability to visualize and detect abnormalities in soft tissues, such as bone marrow, the spinal cord, and…
Conventional Radiography, CT, and MRI in Bone Imaging Most examinations of bone start with conventional radiographs obtained with at least two views exposed at a 90-degree angle to each other (called orthogonal views ) so as to localize abnormalities better…
How MRI Works Because magnetic resonance imaging (MRI) uses the molecular composition of tissues, especially water, it is particularly sensitive to detecting soft-tissue abnormalities in much higher detail than CT scans, although the two imaging modalities are complementary. MRI produces…
In this chapter, we will discuss some additional applications of ultrasound, including vascular ultrasound, pediatric applications of ultrasound, and point-of-care ultrasound. Vascular Ultrasound Vascular ultrasound uses both B-mode (gray-scale) ultrasound and Doppler ultrasonography— a combination called duplex sonography —to display…
Ultrasound (US) is a diagnostic imaging tool that makes use of probes (transducers) that can produce an acoustical frequency that is hundreds of times greater than humans can hear and which uses that acoustical energy to localize and characterize human…
In this chapter, you will learn how to recognize some of the most common abnormalities in the abdomen. We will also discuss selected hepatic abnormalities. Chapter 19 , on ultrasound, describes some of the more common biliary and pelvic abnormalities.…
Soft-tissue calcifications lend themselves to a systematic approach that ties together a diverse group of diseases. Although this chapter focuses primarily on abdominal calcifications, the same principles and approach apply to dystrophic calcification found anywhere in the body. Most soft-tissue…
Recognition of extraluminal gas is an important finding that can have an immediate effect on the course of treatment. Air is normally not present in the peritoneal or extraperitoneal spaces, bowel wall, or biliary system. Air outside of the bowel…
In Chapters 13 and 14 , we discussed how to recognize the normal intestinal gas pattern on conventional radiographs and computed tomography (CT). In this chapter, you will learn how to recognize and categorize the four most common abnormal bowel…
Introduction to Abdominal and Pelvic CT It is estimated that around 80 million computed tomography (CT) scans of all kinds are performed in the United States each year. Almost 10% of all visits to the emergency department are for abdominal…