What does contrast give?
Without contrast, parenchymal organs look uniform, and small formations in them are lost. The contrast changes the picture fundamentally: in the arterial phase, richly supplied blood formations are visible, in the venous phase - most metastases and the structure of the liver, in the delayed phase - the urinary tract. Based on the nature of accumulation over time, the doctor distinguishes with high certainty between hemangioma, metastasis, abscess and primary tumor. This is the standard for oncological investigation and staging, when pancreatitis with necrosis is suspected, when searching for the source of bleeding and when assessing the vascular structures of the abdominal cavity.
What is the power of computed tomography?
MSCT creates an image using X-rays and produces thin sections with high spatial resolution. It is indispensable where bone, lung tissue, fresh hemorrhage and precise vessel geometry are important, as well as in emergency situations - the examination takes seconds.
Three-dimensional reconstructions are constructed from the resulting sections: this allows the surgeon to see the anatomy in volume in advance and plan the intervention.
When you need contrast
Intravenous contrast dramatically increases the information content in the study of blood vessels, tumors, inflammatory processes and parenchymal organs. It shows the nature of the blood supply to the formation, which often determines its nature.
Before a contrast study, kidney function is assessed by creatinine level and an allergic history is clarified - reactions to iodine-containing drugs are rare, but require attention.
CT or MRI
- CT scan is better: bones, lungs, acute hemorrhage, stones, vessels, emergency conditions
- MRI is better: brain and spinal cord, soft tissues, joints, pelvis, liver
- CT is faster and more accessible, MRI does not provide radiation exposure
About radiation exposure
Computed tomography uses x-rays and is therefore prescribed according to indications. Modern machines use dose reduction protocols, and the information obtained from sound research usually far outweighs the risk. During pregnancy, CT scans are performed only for health reasons.