In this article, you will learn about the Helical CT and High-resolution CT. The purpose of a CT Scan is to reveal your body’s internal structures. In addition, you’ll learn about the risks of a CT scan, including a possible allergic reaction to the contrast material. You can also get an overview of the procedure and ask your doctor questions. Regardless of which type of CT scan you need, you’ll likely find it useful to have an understanding of its purpose and advantages.
High-resolution CT
A high-resolution CT scan is a noninvasive imaging technique that uses a narrow beam of X-rays and sophisticated computer analysis to produce highly detailed pictures of your body. The images produced by the scan are clear enough to allow your doctor to see even the tiniest details in your body. A team of specialists at Cedars-Sinai S. Mark Taper Foundation Imaging Center will perform your CT scan. A comfortable dress is recommended for the scan.
The HRCT is a diagnostic tool used to monitor lung disease, monitor treatment response, and select biopsy sites. A high-resolution CT scan can reveal many details that may be difficult to see with conventional methods, including subtle alterations in lung anatomy. In patients with idiopathic pulmonary fibrosis, the procedure is important for detecting underlying lung diseases. In patients with lung cancer, it is useful for detecting basal disease because it can reduce the presence of dependant atelectasis.
A traditional CT scan uses 0.625 mm x 128 slices. The x-ray tube rotates while the patient’s table moves through the scanner. Afterwards, a special computer program reconstructs the images into three-dimensional representations of the body. The process requires less radiation than a traditional CT scan. It can also help a physician detect cancer earlier than other methods. If you are unsure if the procedure is right for you, contact a medical physicist for an explanation.
Helical CT
In the past, CT machines have been used to view the body’s internal structures, but the technology has evolved over the years. Helical CT machines, also known as spiral CT machines, are capable of processing continuously changing cross sections of a patient’s body. Computer software uses the data from each slice to produce a three-dimensional volumetric image. The patient is positioned on a table that is translated or moved in between axial scans, which are combined into one full volume image.
The helical CT scanning technology allows for fast acquisition of angiographic type images, with no risk to the patient. Unlike contrast-enhanced CT, this procedure uses a slip-ring design. The gantry rotates around the table, transferring CT data continuously as it moves. The data from the scan is restructured at every slice increment, resulting in a continuous helical “ribbon” of data. This technology reduces the risk of missing small tumors and other abnormalities by a factor of eight to ten. It is also 8-10 times faster than a conventional CT scan. Helical CT is especially helpful for the elderly, young, and acutely injured patients.
The patient will be positioned on a motorized exam table. The technologist will be in a control room, which allows him or her to monitor the patient. The patient can hear and speak with the technologist through an intercom or video camera inside the scanner. The patient will be asked to remain still during the scan. The technologist will ask the patient to breathe deeply during the procedure, as moving the body will cause the X-ray images to be distorted. The technologist may move the table to take a different picture of the body, and may even tell the patient to hold on to their breath.