Positron emission tomography (PET) is an advanced medical imaging technology widely used for the diagnosis and treatment tracking evaluation of cancer, neurological diseases, etc. due to its sensitivity, safety, and non invasiveness. Before and after undergoing PET examination, patients need to follow a series of precautions to ensure the accuracy of the examination and patient safety. If there is a history of diabetes, tumor, surgery or drug allergy in the past, and the female subject is in pregnancy or lactation, it is necessary to explain in detail to the doctor so that the doctor can make corresponding inspection adjustments and arrangements. At the same time, it is necessary to bring the recent inspection report and medical records, so that the doctor can better understand the specific situation of the examiner and more specifically arrange the inspection. With the popularization of PET/CT and PET/MRI examinations, patients still need to have a basic understanding of PET examinations to prevent negative emotions such as radiation fear, enhance their confidence in the examination, prevent deviation in examination results due to inadequate patient cooperation, improve clinical diagnostic accuracy, and maximize patient benefits.
In addition to complying with the overall requirement of prohibiting the wearing of metal objects during CT and MRI examinations, what are the areas that need to be noted before, during, and after PET examinations?
Preparation before PET examination:
1. Appointment: PET examination needs to be scheduled in advance. On the one hand, it is a matter of time, and on the other hand, the radioactive drugs used by the patient during the PET examination process are all produced and prepared on the same day. Doctors need to prepare the dosage of the drugs in advance according to the patient's specific situation, in order to facilitate the smooth progress of the examination.
2. Diet: It is usually necessary to maintain a fasting state for 4 to 6 hours before undergoing PET examination. Patients should arrange their diet in advance according to the doctor's advice to ensure that their body is in the most suitable state, and avoid drinking alcoholic, sugary, coffee and other beverages; Choose high protein/low-carbon foods for diet.
3. Drinking water: Although it is necessary to maintain an empty stomach, patients usually follow the doctor's instructions and drink water appropriately. Adequate hydration helps promote the excretion of injected radioactive drugs, which is beneficial for the accuracy of the examination.
4. Blood glucose: The most commonly used imaging agent in PET examination is 18F-FDG, a glucose analog. Therefore, diabetes patients or patients with high blood sugar need to consult the doctor before the examination, carry hypoglycemic drugs with them on the day of examination, and actively inform the medical staff of the type and usage of hypoglycemic drugs currently used.
5. Other: Empty the bladder before examination, and avoid contaminating clothing and body surface with urine during urination, which may affect image diagnosis.
Attention during PET examination:
1. Injection of radioactive drugs: PET examination involves injection of radioactive drugs, and patients should remain calm and cooperate with medical staff before injection. PET radiopharmaceuticals are crucial in examinations and typically require scanning 40-60 minutes after drug injection (depending on the specific imaging agent and examination purpose).
2. Examination process: PET examination usually requires the patient to remain relatively stationary in the machine, and large movements can produce motion artifacts, affecting imaging quality and potentially leading to rescanning. Patients need to cooperate with the examination according to the doctor's instructions to ensure the clarity and accuracy of the images.
Attention after PET examination:
1. Delayed scan: After the patient's scan is completed, they will wait for notification in the waiting area. They can leave once the scan quality is qualified or the examination is completed. However, a small number of patients require a second scan after the first scan, which is a delayed scan. This is usually due to the doctor's doubts about the lesions displayed in the first scan, or unclear images caused by factors such as body shaking during the scan, which affects the diagnosis. Therefore, a second scan should be performed after a period of imaging agent metabolism.
2. Drinking water: After PET examination, patients usually need to increase their water intake. This helps to promote faster elimination of radiopharmaceuticals and reduce the radiation dose in the patient's body.
3. Avoid close contact: After PET examination, patients should avoid close contact with infants, pregnant women, or other individuals who are particularly sensitive to radiation to reduce the risk of radiation transmission.
4. Follow medical advice: After PET examination, patients need to follow the doctor's advice, especially avoid participating in other radiation examinations, to prevent excessive accumulation of radiation dose.
Conclusion: Precautions before and after PET examination are crucial for ensuring the accuracy of the examination and the safety of patients. Patients should actively communicate with doctors, understand and follow their orders, to ensure the best results during the examination process. This not only helps to provide accurate medical information, but also provides scientific basis for patient diagnosis and treatment, while maximizing the protection of patient health and safety.