CT of the knee joint (without contrast)

CT of the knee joint

A paper referral from a doctor is required to take the test.

A computed tomography of the knee joint is useful in the diagnostics of articular conditions, degenerative lesions, as well as after injuries to or inflammations of the joints. The examination involves taking several pictures using X-rays. The patient lies down on a special table which slides to the inside of the machine, into the gantry.

Once the patient is inside the gantry, an X-ray generating lamp is rotated around the patient’s body on a special frame. Passing through particular tissues of the patient’s body, the radiation becomes weaker. The degree of radiation depends on the type of tissue is has to pass through, e.g. through the bones, the X-ray wave is severely weakened, whilst when passing through air – the X-ray’s weakening degree is at a minimum.

This phenomenon makes it possible to precisely differentiate between the particular tissues in the patient’s body. Moreover, the X-ray lamp installed in the gantry, rotating around the patient’s body, illuminates every single point along its longitudinal axis, thereby providing the opportunity to obtain images of the selected layer of the patient’s body on a screen.

The images obtained after each rotation of the lamp around the patient’s body (360°) are then summed up by a computer and displayed on a monitor as an image of anatomical structures from the particular transverse layers of the patient’s body.There is an additional option of the so-called secondary image processing, which involves setting and calculating the grey scale of the image, as well as measuring distances, surface areas, etc.). It is also possible to reconstruct the image in a plane other than the transverse one (e.g. the frontal plane) or even in three-dimensional pictures.

During the examination, the patient must not move to guarantee clear and sharp images. It is also important to remove all metal items from clothes and body, which might otherwise affect the quality of the images obtained.

A Damian Medical Center consultant will call you within 24 hours of purchase to arrange a specific test date.

Preparation for the CT scan of the knee joint:

• This examination may only be performed upon presenting a medical prescription (valid for 3 months) on the examination day in paper form.
• Patients are requested to bring any previous medical documentation (CT, ultrasound, X-ray and MRI scans, hospital discharge reports and outpatient treatment reports). It is necessary to arrive 15-20 minutes before the examination at the reception desk (level -1) in order to fill in a mandatory form concerning the patient’s health (diseases, drug use, allergies, physiological condition, injuries, past surgeries).

The type and scope of the examination is ultimately determined by the radiologist supervising the examination – the radiologist, therefore ultimately decides whether to administer the contrast agent or not, or whether the examination should encompass a particular body part or a different one, or – for example, two at a time. In such cases, an extra payment may be required.

Contraindications to the CT scan of the knee joint

A paper referral from a doctor is required to take the test.

The main contraindication to the CT scan of the bones is pregnancy or a suspected pregnancy. If the patient suspects that she might have become fertilised, she should report this fact to the personal doctor. The X-ray used during the CT scan may adversely affect the health of the foetus. Moreover, due to the fact that the CT radiation is much higher than the X-ray one, CT scans are performed only upon presenting a written medical prescription.

Too frequent performance of the examination without medical indications may adversely affect the patient’s health. If it is necessary to administer a contract agent, there are the following contraindications:

• allergy to iodine contrast agents;
• severe circulatory insufficiency (failure);
• renal insufficiency (failure);
• haematological diseases;
• nephropathy.