Nuclear Medicine is a functional imaging specialty that uses radiopharmaceuticals to visualize physiological processes such as metabolism, perfusion, and receptor activity. It provides molecular‑level information that cannot be obtained with CT, MRI, or ultrasound.
Common Nuclear Medicine studies include bone scans, thyroid imaging, renal scans, hepatobiliary imaging, cardiac perfusion studies, and PET/CT.
Nuclear Medicine uses radiopharmaceuticals that emit gamma rays or positrons. These tracers accumulate in specific organs or tissues, allowing imaging of physiological function. A gamma camera or PET scanner detects emitted radiation and reconstructs images.
Technetium‑99m is the most widely used isotope due to its ideal half‑life and low radiation dose. PET imaging uses positron‑emitting tracers such as F‑18 FDG to assess metabolic activity.
Nuclear Medicine is essential for diagnosing cancer, cardiac disease, endocrine disorders, infections, and skeletal abnormalities.
Source: Society of Nuclear Medicine and Molecular Imaging
Nuclear Medicine provides unique functional information that often detects disease before structural changes occur. It is indispensable in oncology, cardiology, endocrinology, and orthopedics.
Cardiac perfusion imaging evaluates myocardial blood flow and identifies ischemia. Bone scans detect fractures, metastases, and infections. Thyroid uptake scans assess hyperthyroidism and nodules.
PET/CT combines metabolic and anatomical imaging, making it essential for cancer staging, treatment planning, and monitoring response to therapy.
Source: American College of Radiology
Bone Scan
Thyroid Scan
PET/CT
Technetium‑99m
Iodine‑123 / I‑131
F‑18 FDG
Oncology & Metastasis
Cardiac Perfusion
Endocrine & Renal Imaging
Source: SNMMI
Nuclear Medicine facilities follow accreditation standards from the American College of Radiology (ACR) and the Intersocietal Accreditation Commission (IAC). These standards ensure proper radiopharmaceutical handling, equipment performance, and technologist competency.
Quality control includes daily uniformity checks, energy peaking, sensitivity testing, and dose calibrator accuracy.
Source: ACR / IAC
Is Nuclear Medicine safe? Yes. Radiation doses are low and tracers decay quickly.
How long does a scan take? Most exams take 30–90 minutes depending on uptake time.
What is PET/CT? A hybrid scan combining metabolic PET imaging with anatomical CT.
Source: SNMMI
Nuclear Medicine technologists require training in radiation physics, radiopharmacy, instrumentation, patient care, and imaging protocols. Certification is available through ARRT and NMTCB.
Students learn to prepare radiopharmaceuticals, operate gamma cameras and PET scanners, and ensure radiation safety.
Source: NMTCB