Computed tomography (CT) of the adrenal glands is a modern, informative, gentle research method that allows timely detection of adrenal gland pathologies and the decision on surgical intervention.
The role of the adrenal glands
These are paired organs located above the upper ends of the kidneys. Distinguish between the adrenal cortex (90%), located immediately under the capsule, and the medulla. These structures are considered as two separate endocrine glands, since they are separated from each other by a connective tissue capsule and secrete hormones of different function and structure.
Three layers are distinguished in the cortical substance: glomerular - produces aldosterone, fascicular - produces glucocorticoids (cortisone, cortisol, corticosterone), and reticular - sexhormones (male and female). The medulla produces adrenaline and norepinephrine.
Pathologies of the adrenal glands
The most common adrenal gland pathologies are:
- Hyperaldosteronism is a pathological condition of the body caused by excessive production of the hormone aldosterone by the adrenal cortex. Aldosterone regulates water-s alt metabolism: it enhances the reabsorption of sodium from the primary urine and excretes potassium in the urine. Excess aldosterone causes sodium retention in the body. Since sodium attracts water to itself, it leads to edema, an increase in the amount of blood and an increase in pressure. There are causes: primary - associated with damage to the adrenal glands themselves, secondary - associated with the work of the hypothalamic-pituitary system of the brain or other factors not localized in the adrenal glands.
- Cortex deficiency. In 98% of cases it has an autoimmune origin. The course of pathology and signs are mainly due to a lack of cortisol and aldosterone. Treatment is hormone replacement therapy.
- Congenital hyperplasia of the adrenal cortex. It is characterized by insufficient production of corticosteroids and proliferation of the adrenal cortex. Treatment is hormone replacement therapy.
- Pheochromocytoma is a tumor that secretes adrenaline and norepinephrine. Malignant in 10% of cases.
Indications for computed tomography of the adrenal glands
The doctor will send to do a CT scan of the adrenal glands in case of:
- benign or malignantadrenal tumors detected by ultrasound;
- the need for differential diagnosis of hyperplasia and adenoma;
- lower or higher blood pressure;
- deepening of the voice in women, excess hair growth on the body or face;
- breast enlargement in men;
- dramatic weight gain;
- muscle weakness, reduced muscle strength;
- lesion of the abdominal lymph nodes.
What is contrast
CT of the kidneys and adrenal glands is always performed using a contrast agent. It is necessary to enhance the image. A CT scan of the adrenal glands without contrast will not allow differentiation of individual parts of the adrenal glands from surrounding tissues, for example, from the vessels of the spleen.
As contrast agents, iodine preparations are used, which are administered intravenously or, when examining the intestines, orally. For CT of the adrenal glands with contrast, non-ionic low-osmolar preparations with an iodine content of 320-370 mg/ml are used. The drug is administered at a rate of 3-5 ml/s. A patient weighing 70-80 kg will be injected with 70-120 ml of the drug. 99% of the drug is excreted through the kidneys.
Contraindications
CT is a gentle procedure. However, certain risks exist:
- X-rays increase the chance of developing cancer;
- contrast agents can cause allergies;
- contrast agent has a negative effect on the kidneys.
The listed possible consequences determine the list of contraindications for CTAdrenal:
1. Absolute:
- pregnancy, because X-rays adversely affect the development of the fetus;
- overweight - if you are over 120kg, check if your CT machine has weight limits;
- metal prostheses or implants that cannot be removed.
2. Relative:
- age up to 12 years old - up to three years old the child will not be able to lie still on the table of the device, but even for older children, x-ray exposure is dangerous;
- hyperkinesis or convulsive syndrome, which will not allow the patient to be immobile;
- claustrophobia, mental disorders;
- breastfeeding.
To minimize radiation exposure to pregnant women and children, reduce the duration of the study, reduce the current on the x-ray tube, reduce the number of phases of tomography, increase the turnaround time of the tube. For children, in some cases, it is possible to use sedatives. The mammary glands of breastfeeding women are covered with bismuth screens.
3. With contrast:
- Severe allergy to contrast agents (shock, convulsions, respiratory arrest) - tell your doctor if you have even a mild allergy to iodine or seafood (nausea, urticaria, Quincke's edema), in which case you will need to enter antiallergic drugs (prednisolone) and use non-ionic contrast agent solutions;
- severe asthma or allergic disease;
- heavykidney failure - intravenous contrast agents are excreted through the kidneys and can interfere with their work;
- diabetes - tell your doctor if you are taking metformin, which is toxic to the kidneys, in which case you will need to stop taking it some time before the procedure;
- hyperthyroidism,
- heavy general condition.
Preparation for Adrenal CT
If only the adrenal glands (not the intestines) are to be CT scans, no bowel cleansing or diet is required. If a CT scan of the adrenal glands with contrast is planned, it is necessary to refrain from eating for 6 hours. This will reduce the chance of vomiting and nausea in response to the contrast medium.
Preparing for the procedure
A CT scan of the adrenal glands lasts no more than 10 minutes. Most of this time is spent preparing the patient.
Preparation for the procedure includes:
- Changing into a medical shirt. Tight elements of ordinary clothing, locks, buttons will leave shadows on the pictures and make it difficult to diagnose.
- Administration of intravenous contrast agent in case of adrenal CT with contrast.
Patient may experience:
- flux of heat throughout the body;
- metal taste;
- nausea;
- slight burning sensation.
These sensations will pass in a few seconds. It is extremely rare to experience adverse reactions to intravenous contrast: Quincke's edema, shortness of breath, bradycardia. To eliminate thematropine, oxygen, beta-agonists, adrenaline will be introduced. Severe reactions - shock, respiratory arrest, convulsions, collapse - require resuscitation. All severe reactions develop within 15-45 minutes after contrast injection. Therefore, you need to be under the supervision of a doctor this time.
Tell your doctor right away if you have:
- dizziness;
- facial swelling;
- itchy skin, rash;
- sore throat;
- bronchospasm;
- uncharacteristic arousal,
Positioning the patient on the tomography table - you will need to lie on your back with your arms up. Any movement will result in fuzzy images, and the pathology will be difficult to diagnose, so pillows or straps are used if necessary.
Procedure
The adrenal CT procedure itself will go like this:
- Personnel will leave the room before turning on the appliance. You can call the doctor at any time or use the panic button.
- During the procedure, a slight noise or crackling of the device will be heard, pain and discomfort should not be.
- When the patient is inside the device, the scanning beam begins to rotate around him. Layered images will be visible on the computer monitor - slices 0.5-0.6 mm thick. When superimposed on each other, a three-dimensional model of the adrenal region is obtained. The patient will be asked to hold their breath several times while inhaling.
- First take some group shots.
- Then, contrast is injected through the catheter, pictures are taken in the arterial and venous phase, delayed pictures.
- Afterthe end of the procedure, the catheter is removed from the vein, the patient changes into his clothes.
The radiologist will need 30-60 minutes to analyze the images and draw up a conclusion with a seal and signature.
Identified diseases
Detected by CT:
- adrenal adenoma is a benign neoplasm;
- malignant neoplasms;
- lipomas, hematomas, cysts;
- adrenal tuberculosis;
- involvement of nearby tissues in the pathological process (for example, lymph nodes).
Can be differentiated by CT of the adrenal mass:
1. Kore:
- hyperplasia - overgrowth;
- adenoma - benign tumor;
- cortical carcinoma - cancer of the epithelium of the adrenal cortex;
- mesenchymal tumors (fibromas, angiomas) - benign or malignant tumors from connective, vascular, adipose, muscle, and other soft tissues;
- neuroectodermal tumors - benign or malignant tumors that develop from the rudiments of the nervous tissue;
- hematomas - hemorrhages;
- cysts - pathological cavities in the body.
2. Medulla:
- chromaffin tissue tumors;
- tumors of non-chromaffin tissue.
3. Mixed Education:
- corticomedullary adenoma;
- corticomedullary carcinoma.
How are adrenal pathologies diagnosed?
Pathology of the adrenal glandsis found in two cases.
1. The appearance of clinical signs of excessive synthesis of hormones.
The excess of each hormone manifests itself in its own way. For example, in the case of hyperaldosteronism (excess aldosterone), the patient complains of high blood pressure, periodic cramps, and muscle weakness. Then the doctor directs the patient to take blood and urine tests and do an ultrasound of the adrenal glands. The reason for the high content of aldosterone can be: cirrhosis of the liver with ascites, chronic nephritis, heart failure, diet poor in sodium, excess potassium in food, toxicosis of pregnant women. All of these conditions increase the activity of renin, which stimulates the production of aldosterone. The diagnosis will be made, the treatment will be prescribed. CT is not needed.
If the cause remains undiagnosed, or any adrenal masses are found on ultrasound, the patient may be referred for CT of the kidneys and adrenal glands with contrast. The contrast agent stains the cells of benign and malignant tumors differently, which makes it possible to distinguish them from each other. CT will give an answer whether the tumor is benign or malignant. For example, a common cause of excess aldosterone is an adenoma of the glomerular zone of the adrenal cortex, a benign tumor.
2. Accidental detection of a tumor of the adrenal gland during an ultrasound or CT scan without contrast enhancement of the abdominal organs. The patient will be referred for CT of the adrenal glands with intravenous contrast enhancement. CT will give an answer: benign tumor or malignant. If the tumor was discovered by chance, as a rule, it is hormonally inactive.
Treatment of adenoma and other benign formations
Small benign tumors that do not secrete hormones are not treated. They are monitored by repeated CT scans without contrast once a year, they analyze the level of cortisol and some other indicators in the blood. For example, 20-40% of detected tumors that are accompanied by elevated levels of aldosterone are not removed. Large benign tumors (more than 4 cm) or hormone-producing tumors are surgically removed.
Surgery to remove a benign tumor of the adrenal gland can be performed in three ways: open, laparoscopic and retroperitoneoscopic (lumbar). More often performed in an open way, although it is the most traumatic of all.
Treatment of malignant tumors
The most successful treatment for adrenal cancer is complete surgical removal. It is desirable to remove the nearest to the tumor and enlarged lymph nodes, which will increase the life of the patient. When a tumor grows into the kidney, the kidney is also removed. Most often, the adrenal gland is removed by an open method. Laparoscopy is not recommended for tumors larger than 5 cm or for lymph node metastases.
