Computed Tomography Quiz Test! Trivia

Crohn's disease is a chronic inflammatory condition that primarily affects the gastrointestinal tract. It causes inflammation and damage to the lining of the digestive system, leading to symptoms such as abdominal pain, diarrhea, and weight loss. The disease can affect any part of the gastrointestinal tract, from the mouth to the anus. It is characterized by periods of flare-ups and remission, and the exact cause is still unknown. Crohn's disease is different from other inflammatory bowel diseases like ulcerative colitis, which primarily affects the colon and rectum.

Given that the area on the scan has an associated measurement of 900HU, it is most likely to be composed of bone. This is because bone typically has a higher density compared to other tissues in the body, such as fat, water, or air. The Hounsfield Unit (HU) scale is used in medical imaging to measure the density of different tissues, with bone having a higher HU value due to its higher density. Therefore, the measurement of 900HU suggests that the area is composed of bone.

A voxel is a three-dimensional volume element, often used in medical imaging and computer graphics. It represents a single point within a three-dimensional space and is analogous to a pixel in two-dimensional images. Therefore, voxel is another term used to describe a volume element.

In filming the brain, it is common practice to use a wider window width through the posterior fossa to reduce the appearance of beam hardening artifacts. Beam hardening artifacts occur when the X-ray beam passing through different materials in the body gets hardened, leading to streaks or dark bands in the image. By using a wider window width, the range of X-ray energies that contribute to the image is increased, reducing the visibility of these artifacts and improving the overall image quality.

A CT study of the brain may visualize glioblastoma, which is a type of brain tumor. Glioblastoma is an aggressive and malignant tumor that arises from the glial cells in the brain. It is often characterized by its rapid growth and invasion into surrounding brain tissue. CT scans can help detect glioblastoma by showing abnormal areas of increased density or mass in the brain. This imaging technique can provide valuable information about the location, size, and extent of the tumor, which is crucial for diagnosis and treatment planning.

Adjusting the angle of the gantry and widening the window can help reduce the effect of dental filling in a sinus study. By adjusting the angle of the gantry, the dental filling can be positioned out of the field of view, minimizing its impact on the study. Widening the window can increase the range of pixel values displayed, allowing for better visualization of the sinus area and reducing the prominence of the dental filling.

The correct answer is "a mathematical formula for processing data". When selecting an algorithm, the tech is choosing a specific mathematical formula that will be used to process the data. Different algorithms can be used to manipulate and analyze the data in different ways, depending on the desired outcome. This choice of algorithm is crucial in determining how the data will be processed and ultimately interpreted.

Scans of the pituitary taken in the coronal plane have the advantage of reducing or eliminating streak artifacts. Streak artifacts are unwanted lines or streaks that can appear on the image, often caused by dense structures or metallic objects. By using the coronal plane, which is a vertical slice from front to back, these artifacts are minimized or removed, resulting in a clearer and more accurate image of the pituitary gland. This allows for better visualization and interpretation of the scan.

The pineal gland is a small pine cone-shaped structure located in the brain. It is responsible for producing and secreting melatonin, a hormone that regulates sleep-wake cycles. In CT images, the pineal gland can often be seen as calcified, appearing as a bright spot. This calcification is a normal age-related process and is more commonly seen in older individuals. The other options listed (choroid plexus, caudate nucleus, and middle cerebral artery) are all structures in the brain but do not typically appear calcified in CT images.

A bolus of IV contrast, followed by rapid sequence scanning, can be used to improve visualization of small pituitary lesions. This technique involves injecting contrast dye into the patient's bloodstream, which enhances the visibility of the lesions during the scan. Rapid sequence scanning refers to performing the scan immediately after the contrast injection, allowing for real-time visualization of the lesions. This method is effective in highlighting small pituitary lesions and obtaining clear and detailed images for accurate diagnosis and treatment planning.

The semicircular canals in the inner ear play a crucial role in the sense of equilibrium. These canals are filled with fluid and are responsible for detecting rotational movements of the head. When the head moves, the fluid inside the canals also moves, which in turn stimulates hair cells that send signals to the brain, allowing us to maintain our balance and sense of spatial orientation. The other options mentioned, such as incus, epitympanic recess, and superior sagittal sinus, are not directly involved in the sense of equilibrium.

The pancreas is the organ that produces the digestive enzymes protease, lipase, and amylase. These enzymes are essential for breaking down proteins, fats, and carbohydrates in the digestive system. The pancreas releases these enzymes into the small bowel to aid in the digestion and absorption of nutrients. The gallbladder stores and releases bile, which helps in the digestion of fats, but it does not produce the digestive enzymes mentioned. The stomach produces gastric juices, including pepsin, which aids in protein digestion, but it does not produce the specific enzymes mentioned. Therefore, the correct answer is the pancreas.

The normal range of CT attenuation measurements for a non contrasted liver in an adult PT is 38 to 80 HU. CT attenuation measurements are used to assess the density of tissues and structures in the body. In this case, the range indicates the normal density range for the liver without the use of contrast agents. Values outside this range may indicate abnormalities or pathology in the liver.

Pleural effusion is the accumulation of fluid in the thoracic cavity, specifically between the visceral and parietal pleurae. This condition occurs when fluid escapes into the pleural space, leading to an excessive amount of fluid in the area surrounding the lungs.

The enhancement of most brain lesions is due to the disruption of the blood brain barrier. The blood brain barrier is a protective barrier that prevents certain substances from entering the brain tissue. When there is damage or inflammation in the brain, the blood brain barrier can become compromised, allowing contrast agents to leak into the brain tissue. This leakage causes the lesions to appear enhanced on imaging studies, making them more visible and easier to detect.

Performing a precontracted study on the abdomen along with the post-contrast images is essential when the entire liver cannot be imaged before the equilibrium phase. This is because the precontrast study helps in identifying any abnormalities or lesions in the liver that may not be clearly visible in the post-contrast images alone. By comparing the precontrast and post-contrast images, a more accurate diagnosis can be made.

The advantage of using a spiral scan technique for a thorax study is that it is less likely to miss small lesions. This is because the spiral scan technique allows for continuous and uninterrupted scanning of the thorax, capturing a more comprehensive view of the area being studied. By eliminating any gaps or spaces between individual scans, the likelihood of missing small lesions is reduced, improving the accuracy and reliability of the study results.

The area within the gantry for which raw data are acquired is called the SFOV (Scanning Field of View). This refers to the specific region that is captured by the imaging system during a scan. It determines the extent of the anatomical area that will be visualized in the resulting image.

The right ventricle sends blood to the lungs. This is because the right ventricle receives deoxygenated blood from the right atrium and pumps it to the lungs through the pulmonary artery. In the lungs, the blood is oxygenated and then returned to the left atrium through the pulmonary veins.

When possible, the normal side should be examined, with the two sides placed symmetrically. This means that when conducting CT studies of the musculoskeletal system, it is important to compare the affected side with the normal side to identify any abnormalities or differences. By examining both sides symmetrically, it allows for a more accurate assessment and comparison of the musculoskeletal structures.

The correct answer is that a typical presentation of an abscess on a contrast-enhanced CT study is a low attenuation area surrounded by a ring of enhancement. This means that the abscess appears as a darker area with reduced density compared to the surrounding tissue, and it is surrounded by a brighter ring of increased density due to the contrast material. This pattern is commonly seen in abscesses and helps to differentiate them from other types of lesions or fluid collections.

Using a partial scan to create an image means that only a portion of the object or area being scanned is captured. This limitation arises because the scan data cannot be retrospectively segmented, meaning that it is not possible to go back and extract specific details or sections from the scan after it has been completed. This can be problematic if there is a need to focus on a particular area of interest or if further analysis or measurements need to be made on specific regions within the image.

The slice spacing in a CT study refers to the distance between consecutive slices. The radiation dose to the patient (PT) is affected by the slice spacing because a smaller spacing requires more slices to be taken, resulting in a higher radiation dose. Therefore, the radiation dose to the PT is directly influenced by the slice spacing in a CT study.