CT of the knee joint
Computed tomography of the knee joint is one of the methods of x-ray examination, the results of which are analyzed by a computer program. The result is a series of images reflecting the layered structure of the knee joint.
Using this research method could diagnose various diseases in the preclinical stage of their development, not to mention the long-existing pathological processes.
Computed tomography do not under the following conditions (contraindications):
- persistent and intense pain, not allowing long time to keep the leg straightened at the knee;
- breast-feeding (this is a contraindication to treat CT scan with contrast, as the substance can penetrate into mother’s milk);
- intolerance to iodine (contrast study);
- severe liver failure (this also applies to the administration of contrast material).
The preparatory phase and the nature of the investigation
CT without contrast does not require a preparatory period. However, before a CT with contrast, you need to avoid food intake 4 hours prior to the introduction of this substance.
The procedure is painless (but in the case of the occurrence of various unpleasant symptoms, or subjective discomfort with the help of a special button, you must immediately put honey.staff informed). It lies in the fact that the patient lies motionless on the table-couch, which moves relative to the scanner. This gives the opportunity to produce a series of images, passing through the mutually perpendicular plane.
Note! At the time of scanning the person must be stationary, so that the image is most clear.
The efficacy and diagnostic value of CT
Computed tomography of the knee joint shows changes that are typical for the following diseases:
- intra-articular fractures of the femur, tibia or fibula;
- deforming osteoarthritis of the knee joint;
- inflammatory lesions of the joints (heartit);
- chondroblastoma – tumor of cartilage;
- dislocations – both full and incomplete;
- osteoblastoma is a benign tumor of bone tissue;
- osteosarcoma – malignant bone tumors;
- osteomyelitis – inflammation of the medullary canal.
Computed tomography also provides an opportunity to assess how successful were conservative treatment (use of drugs, physiotherapy, etc.). Also, with CT you can evaluate the effectiveness of knee surgery. The study besides widely used as a diagnostic method before surgery, as it gives the opportunity to study in detail the structure of the joint and the relative position of structures of its components.
Comparative analysis of CT and MRI
What is different about CT or MRI of the knee joint, which is better and what method of diagnosis is to prefer? The differences begin with the principle of the study. In CT on the fabric affects the radiation energy, and MRI is an electromagnetic effect.
This is why MRI is the method of choice for diagnosis of the condition of the knee joint in pregnant women who show any x-ray examination. One or the other method can be performed with contrast. For the CT uses iodinated contrast agents which may lead to the development of allergies. An MRI administered on the basis of gadolinium, a non-allergenic substance.
It should also be noted that the diagnostic value of compare research methods are also different.
Thus, MRI is better allows us to consider such structures as:
- large nerve trunks;
- knee artery;
Computed tomography is particularly well visualizes the bones forming the knee joint. So if you suspect osteoarthritis, osteomyelitis, bone tumors and fractures, this study is indispensable. In turn, MRI is recommended as the primary diagnostic method, when it is required to assess the condition of cartilage and related diseases (chondroblastoma, arthritis in the early stages).