Measurements of glucose (FDG) metabolism are used to determine tumor growth. Because small amounts of FDG can be visualized, early tumor detection is possible before structural changes detectable by MRI or CT occur. Tumor grading can be assessed by the rate of increase in glucose metabolism. In cases of suspected tumor recurrence after therapy, PET differentiates any new growth from necrotic tissue.
PET/CT is used to distinguish between recurrent, active tumor growth and necrotic masses in soft tissue; this differentiation is difficult to make by MRI or CT.
Pretest Patient Care
Explain the purpose, procedure, and special requirements of PET/CT imaging. Refer to standard NMI pretest precautions.
Tell the patient that usually, no special preparation is needed; however, sometimes, a urinary catheter, furosemide, and contrast may be used for abdominal tumors.
Follow guidelines in Chapter 1 for safe, effective, informed pretest care.
Posttest Patient Care
Review test results; report and record findings. Modify the nursing care plan as needed.
Refer to standard NMI posttest precautions.
Follow guidelines in Chapter 1 for safe, effective, informed posttest care.