CT orbit is a layer-by-layer scanning of the orbital cavity with X-ray beams in three projections (lateral, frontal and axial) followed by computer reconstruction of the image. The bone structures of the orbits formed by the frontal, zygomatic, lacrimal bones and the upper jaw are well visualized on tomograms. CT of orbits is the most informative in the diagnosis of traumatic, tumor, inflammatory and other processes in bone tissues.
Indications
CT orbit is prescribed to detect benign and malignant tumors, in particular – hemangiomas of the eye, retinoblastomas. Often, the cause of visual impairment is distant metastases in the eye socket that have spread from other organs affected by cancer. CT orbit is also shown for mechanical damage to the eyes. Scanning allows you to determine the integrity of which structures is violated, as well as to establish the presence of foreign bodies of the eye. As an additional diagnostic method, it is used for conditions such as an eyesore, eyeball atrophy.
CT orbit are also used to detect inflammatory processes. The scan is performed if a pseudotumor of the orbit is suspected, if there is an exophthalmos – protrusion of the eyeball. It is indicated for purulent processes in the eye socket – phlegmon, subperiosteal abscess. With the help of tomographic examination, it is possible to determine the extent of the spread of the pathological focus and determine the subsequent treatment tactics. Also, an indication for CT orbit is the presence of severe pain in the eyes, a rapid decrease in visual acuity.
Contraindications
CT orbit are not prescribed to women during pregnancy because of the likelihood of negative effects on the fetus. A study with contrast is contraindicated in the presence of allergies to iodine-containing drugs, as well as in diabetes mellitus and severe renal insufficiency. During lactation, CT with contrast is prescribed only if the baby is not fed for a period of 2 days.
Preparation for CT
The procedure does not require preparation on the part of the patient. If a scan with contrast is expected, kidney functionality is evaluated. Also, in this case, you need to stop eating 5 hours before the examination.
Interpretation of results
The specialist prints out the CT images received or saves them to a digital medium immediately, an additional written conclusion on the detected changes must be waited for.
In some medical centers in Moscow, you can get the results of an orbit scan half an hour after the examination is completed. This speed is provided by a specialist who proceeds to decipher the tomograms in the process of their implementation. Usually this is a full-time rengenologist working only for this medical center. Network CT centers that provide minimum prices for research often use the services of remote specialists who decode tomograms in their free time from their main work. Therefore, obtaining a conclusion is sometimes delayed for several days.
Based on the results of the scan, it is possible to conclude that the patient has an oncological lesion, determine the type of tumor, its exact localization and the degree of spread to surrounding structures, as well as predict the dynamics of development, determine treatment tactics. When detecting exophthalmos, CT orbit allows to establish the etiology of the disease.
CT orbit are effective in the diagnosis of inflammatory and purulent processes. Based on the data obtained, it is possible to determine the prevalence of the focus on nearby anatomical structures, and make a treatment plan. In the case of foreign bodies, the doctor can assess the degree of tissue damage and conclude that surgical intervention is necessary. A contrast study makes it possible to determine the level of blood supply to the optic nerve and eyeball. With the CT results obtained, the patient should contact his attending physician, who will make an accurate diagnosis and determine the subsequent treatment tactics.
