CT scan or also commonly known as CAT scan is an abbreviation for computed tomography, is a radiological investigation procedure where X-rays are used to image and study the human body and identify any ailments. CT Scan is a non-invasive technique which takes a shorter time to study tissues of the body with great precision and accuracy.
What is the principle of a CT scan ?
A CT scan is based on the principle of X-ray used for imaging of various human body parts. Unlike an X-ray machine where the X-ray radiation are confined to a particular area, a generalized imaging of the body can be done in a CT scan.
Does a CT scan carry more radiation risk than a traditional X-ray ?
Since, traditional X-ray technique is localized to one area the amount of radiation exposure is lesser when compared to a CT scan where more amount of radiation is used to clearly study the organs and associated pathologies.
How does a CT scanner look like ?
A CT scan machine is a doughnut or a box like equipment which has a passageway in the center where the patient is made to lie down on an examination table. The CT scanner is made up of X-ray tubes and detectors which are used to capture images of the body. The machine moves or rotates around this examination table to take images of the required organ or full body at various angles which is then used by the technicians in the control room to develop multiple thin slices of the image. These images are then studied by a radiologist to identify any abnormality.
When is a CT scan advised ?
A CT scan is one of the most common methods of diagnosing diseases as the images produced are detailed and with ultimate clarity. A CT scan is primarily advised when a traditional X-ray is of not much use in diagnosing the condition.
A CT scan can be performed on a particular part of the body or the complete body depending upon the requirement in case of any bone injuries or disorders, tumors, blood clots, swellings, heart ailments, extent of trauma and any ailment which is difficult to diagnose clinically.
A CT scan is also used to help in certain treatments like a needle biopsy, aspiration of a swelling, draining an abscess or determining the status of a tumor, its size and status before and after treatment.
Hence, a CT scan is advised either organ wise like chest, abdomen, liver, kidney spleen, pancreas and urinary tract or for the whole body.
Are CT scans used for general body screening ?
Usually CT scans are not used until a disease or a pathology is suspected, thereby preventing the body from unnecessary radiation exposure.
When is a CT scan not advised ?
A CT scan is based on the principle of X-ray radiation hence the hard tissues of the body are captured as dense images on the scan whereas the soft tissue details are not that precise. Also, in pregnant women when exposure to ionizing radiation is avoided CT scans are usually avoided. In both the above mentioned cases an MRI or Magnetic resonance imaging is preferred.
A CT scan is also avoided in children unless if it is the only requirement, as the exposure to radiation can affect the growth of the child. So if you have to take your child for a CT scan it is advised to have a thorough discussion with your consulting doctor regarding the risks and benefits of the same for your child.
A CT scan is usually not advise in individuals who have multiple myeloma or blood cancers.
In individuals who are severely overweight, getting inside the CT scan may be an issue hence another method of diagnosis should be preferred.
What are the benefits of a CT scan ?
A CT scan is a painless and non-invasive method of body imaging with accurate details which can be lifesaving in certain cases. A CT scan can provide detailed imaging of the hard tissues, soft tissues and the circulatory system thereby detecting any abnormality and its precise location to aid in faster treatment. A CT scan is a cost effective way of diagnosing and confirming a disease or an ailment thereby prevention unnecessary surgical intervention. A CT scan is also beneficial in monitoring certain conditions like cancer before and after treatment.
What are the risks of a CT scan ?
A CT scan carries ionizing radiation which could be harmful to the developing fetus and hence is not advised in pregnant women unless there is no other option available. Some CT scans use contrast material which are dyes (iodine) to have better imaging, these contrast materials may cause an allergic reaction in certain individuals. Also radiation risks are higher in children hence a CT should be advised in children only if it is absolutely mandated.
What is a contrast CT ?
A contrast CT is a special type of CT scan in which a contrast media usually a dye (mainly iodine) to enhance the imaging if advised by the requesting physician. A contrast is usually administered Intravenously or as enema when advised. If your consulting doctor has requested for a contrast CT, it is essential to know the associated risks and benefits of the same.
How do you prepare for a CT scan ?
If your doctor has advised to undergo a CT scan, then you will be advised not to drink or eat anything at least few hours before the procedure. The technician will advise you to wear loose clothes so that the clothes do not interfere with the imaging. You will be advised to remove any pieces of jewelry, Lingerie with underwire and any removable dental prosthesis before the start of the CT scan.
How is a CT scan performed ?
Once you are wearing a loose gown, you will be asked to lie down on your back on the examination table in CT scan room. You will be positioned on the table with the help of belts and pillow to help you relax and prevent any movement during the scan. If a contrast needs to be administered, the technician will administer the same before the start of the procedure. The examination table then moves in the tunnel area where the X-rays are exposed to the desired site to capture detailed image in the form of image slices. These images are then captured and analyzed by a technician in the operating room. You will be asked to remain calm and not to move or breathe heavily during the scan. Typically, a scan takes about 20-40 minutes but faster CT scanners are made available now. If a contrast was administered then you might feel a metallic taste in the mouth, but you will be fit to go home after the procedure.
Who gives the result of the CT scan ?
Once the CT scan is performed, the technician arranges all the desired images/image slices for the radiologist or your surgeon to study and identify the pathology. The report generation may take a while depending upon the type of scan and hospital policy for generation of reports. Immediate reports are generated with the help of a CT scan imaging software for the clinicians to diagnose any life threating conditions or for immediate requirement.
What are the recent advancement in the field of CT scans ?
CT scan are now available with multidtectors or multiple slicing is made possible nowadays delivering faster and more accurate scans. A CT angiogram can be used to obtain a 3D image of the blood vessels in and around the heart. A spiral CT is used to study the lungs usually in cases when lung cancer is detected.
Disclaimer: The content provided here is meant for general informational purposes only and hence SHOULD NOT be relied upon as a substitute for sound professional medical advice, care or evaluation by a qualified doctor/physician or other relevantly qualified healthcare provider.
