adrenal cortex imaging

Cholesterol is the precursor of synthetic adrenocortical hormone. When a radionuclide-labeled cholesterol analog is introduced into the body, it can also be taken up by the adrenal cortex and involved in the synthesis of hormones, and its intake is related to the function of the cortex. Adrenal cortical imaging can show the location, shape, size and functional status of the adrenal cortex, which is helpful in diagnosing certain adrenal diseases. Basic Information Specialist classification: urinary examination classification: urine / kidney function test Applicable gender: whether men and women apply fasting: not fasting Analysis results: Below normal: Normal value: no Above normal: negative: Normal when negative. Positive: Positive: Cushing's syndrome, primary aldosteronism, and hyperhormones. Tips: Adrenal cortical imaging can be combined with dexamethasone suppression test to improve the diagnosis rate. The method was dexamethasone 2 mg/d, which was taken continuously two days before the injection of the tracer until the end of the examination. Normal value normal. Clinical significance 1. Clinical diagnosis of patients with Cushing's syndrome, primary aldosteronism, and hyperkalosis. 2. Cushing's syndrome, primary aldosteronism, hyperkalosis and other patients undergo surgery. 3. After autologous transplantation of adrenal gland. Positive results may be diseases: adrenal medulla hyperplasia, adrenal accidental tumor, primary aldosteronism, adrenal cortical dysfunction associated with mental disorders 1. Adrenal cortical imaging can be combined with dexamethasone inhibition test to improve the diagnosis rate. The method was dexamethasone 2 mg/d, which was taken continuously two days before the injection of the tracer until the end of the examination. 2. Malignant adrenal adenocarcinoma may not be developed, and care should be taken to prevent false negative diagnosis. Inspection process I. Imaging agent 1. 131I-6-iodomethyl-19-demethylcholesterol (NP-59). 2. 131I-19-iodocholesterol (NM-145). 3. 131I-6β-iodocholesterol. Adults use a dose of 37 MBq (1 mCi) / 1.7 m2 body surface area, children reduce. 2. Imaging method 1, slow intravenous injection of imaging agents, and pay attention to observe whether the patient has adverse reactions, a small number of people may appear transient facial flushing, back acid soreness, chest tightness, palpitations and other reactions, can disappear gradually in the short term, generally no special treatment. 2. On the 3rd, 5th, 7th and 9th day after the injection of the imaging agent, the gamma camera or SPECT of the high-energy parallel-hole collimator was used to perform the imaging of the posterior and anterior adrenal glands and their adjacent parts. The matrix is ​​64×64, the energy peak is 364 keV, the window width is 20%, and the acquisition count per frame is about 50-100k or 300s. 3. Dexamethasone inhibition test. In order to further identify adrenal adenomas and hyperplasia after conventional adrenal cortical imaging, inhibition tests can be performed. This test was performed at least one month after conventional imaging. Oral dexamethasone was started 2 days before the injection of the imaging agent, 2 mg/time, once every 6 hours until the end of the examination. The imaging time and method are the same as those of conventional adrenal cortex imaging. Not suitable for the crowd 1. Pregnant women and lactating women should not do this check. 2, severe heart and lung function damage should be used with caution. Adverse reactions and risks A small number of people may have transient facial flushing, sore back, chest tightness, palpitations and other reactions.