CT scanning or CAT scanning and is a noninvasive, painless investigation used to diagnose and treat medical conditions. In this procedure special x-ray equipments are used to produce multiple images of the internal organs of the body in various sections and slicings and a computer joins them together which can be examined on a computer monitor or printed.

 

CT scans of internal organs, bone, soft tissue and blood vessels are much better than x-ray examination. CT scanning of the body is a simple procedure for a patient and it usually lasts between five and 30 minutes.

Indications

• It is one of the best tools for studying the chest and abdomen because it provides detailed, views of all types of tissue.
• It is preferred method for diagnosing many different cancers like lung, liver and pancreatic cancer, since the image allows a physician to confirm the presence of a tumor and measure its size, precise location and the extent of the tumor's involvement with other nearby tissue.
• It is good for diagnosing and planning for management of spinal problems and injuries to the hands, feet and other skeletal structures.
• It is good in the detection, diagnosis and treatment of vascular diseases which may lead to various complications like stroke, kidney failure or even death.
• It is used in the radiation oncology for the planning of the radiation therapy to the tumors
• CT guided biopsies and other minimally invasive procedures
• To plan surgery
• To measure bone mineral density for the detection of osteoporosis
• To identify injuries to the liver, spleen, kidneys or other internal organs in cases of trauma

Procedure

• Patient is positioned on the CT examination table that lies either flat on his back or stomach or on his sides. Straps and pillows are sometimes used to help maintain the correct position and to hold still during the exam.
• Contrast can be administered through oral intravenous or any other routes
• Using the computer the patient table is positioned to a required start point
• Patient is instructed to hold his breath during examination
• If the quality of the exam is good and the desired results are obtained than the patient is asked to leave the laboratory
• CT examinations are painless and generally a fast process
• Spiral CT further reduces the time for investigation
• Some individuals might feel discomfort while lying still on scanner table
• Cases requiring intravenous, patients will feel a slight prick when the needle is inserted into his vein. Patient may experience a warm, flushed sensation during the injection of the contrast materials and a metallic taste after the injection of contrast medium in his mouth that lasts for a few minutes.
• Some allergic patients may develop itching which can be relieved with medication
• Contrast tastes unpleasant
• Patient may feel uneasy if the contrast enema is used as it may result into abdominal fullness
• One of the attendants are allowed in the CT scan room but as a precaution they will need to wear a lead jacket
• After a CT exam, patient can return to normal activities. Special instructions may be given in cases in which some contrast is used

Benefits

• It gives accurate details
• It can produce images of all tissues like bones, blood vessels etc. at the same time
• CT scan provides a detailed image of many types of tissues along with the organs like lungs, bones, and blood vessels.
• CT can reveal any emergency internal injury
• CT is a cost effective imaging study among others routinely used in clinical practice
• CT costs lower than MRI, also it is less sensitive to the patient movement as compared with MRI
• CT does not requires magnetic field so it is suitable for patients who have some medical devices implanted inside their body like Pace Makers
• CT is a real time procedure so is useful in taking biopsies, aspirates and other minimally invasive procedure.

Risks

• Radiations may cause cancer
• Harmful for pregnant woman as it may cause harm to baby
• Iodine containing contrast can lead to allergic reactions requiring emergent action
• Breast fed should be started only after 24 hours of contrast injection