Nuclear Medicine & Molecular Imaging
See disease from the inside — nuclear medicine & molecular imaging
Advanced Precision Diagnostics. Utilizing state-of-the-art technology since 1954.
Dr. Ashok Kumar
Department Overview
Established in November 1957, our department is one of India's pioneering nuclear medicine centers. We were among the first to use radioactive iodine and radioactive gold for cancer diagnosis and treatment - even before the Atomic Energy Establishment began regular isotope supply in 1961. Our founder, Dr. V.M. Sivaramakrishnan, initiated groundbreaking research on radioisotopes and metabolic pathways. Today, we continue this legacy with state-of-the-art gamma cameras and advanced therapeutic nuclear medicine capabilities.
Nuclear medicine imaging differs from conventional scans by focusing on function, not just structure. A small amount of a radioactive tracer is introduced into the body, traveling to specific organs or tissues. A special camera detects the emitted radiation, creating real-time images of biological activity. This allows for earlier detection—identifying cancer at the molecular level often years before structural changes appear on CT or MRI.
Key diagnostic benefits include whole-body mapping in a single scan for complete cancer staging, guiding treatment decisions by confirming metabolic activity, and providing unique functional information for heart, kidney, thyroid, and brain assessment that cannot be obtained from structural imaging alone. The procedures are non-invasive and safe, with radiation doses similar to a few months of natural background exposure.
Both PET/CT and SPECT/CT technologies have important roles in modern medicine. Our nuclear medicine physicians select the best modality for each clinical question based on the target tissue, required sensitivity, and available tracers, ensuring the most accurate diagnostic information for every patient.
What to Expect During Your Visit
Understanding your imaging procedure — a simple guide for patients and families
Referral and Scheduling
Your doctor refers you to our department. Our team reviews the request, selects the appropriate tracer (targeting glucose, PSMA receptors, somatostatin, etc.), and contacts you to confirm preparation instructions (fasting, medications to hold, hydration).
Tracer Injection
On arrival, the radiotracer is administered—usually by a simple intravenous injection, occasionally by inhalation or capsule. The dose is tiny and carefully calculated for your body weight.
Uptake Period
You rest quietly for 30-90 minutes while the tracer distributes to the target tissue. For FDG scans, you will rest in a quiet, warm room to minimise background muscle activity. Uptake time varies for SPECT/CT images based on the specific tracer used.
Scanning
You lie comfortably on the scanner bed while images are acquired. Most whole-body PET/CT scans take 20-30 minutes. SPECT/CT imaging time varies based on the type of scan performed.
Reporting and Results
A specialist nuclear medicine physician analyses your images and issues a detailed report to your referring doctor. Results are typically available within 48 hours. Our team is happy to discuss findings with patients directly.
Frequently Asked Questions
Q: Is the radiation from nuclear medicine scans safe?
A: Yes. The doses used are carefully chosen to provide diagnostic information with minimum exposure. Most PET/CT scans deliver radiation similar to a few months of natural background exposure.
Q: Do I need to fast before my scan?
A: It depends on the scan. FDG PET/CT requires 4-6 hours of fasting to ensure low blood glucose, which maximises tracer uptake. Your specific instructions will be confirmed when booking.
Q: Can I drive after my scan?
A: For most scans, yes. Exceptions include brain scans where sedation may be used. We recommend drinking plenty of water after your scan to help clear the tracer.
Q: What should I tell the team before my scan?
A: Inform us if you are pregnant, breastfeeding, have diabetes, are claustrophobic, or have had recent surgery. Bring a list of current medications.
Q: How long does the whole appointment take?
A: Allow 2-3 hours for most PET/CT scans, including the uptake period. SPECT/CT scans may require 3-4 hours.
Diagnostic Services & Techniques
- PET/CT: Combines functional PET imaging with detailed CT anatomy; gold standard for cancer staging and treatment response.
- PET/MRI: Next-generation hybrid with superior soft-tissue contrast; ideal for brain, liver, pelvis, and paediatric imaging.
- SPECT/CT: 3D functional imaging fused with CT for precise localisation of bone, cardiac, thyroid, and renal function.
- PSMA PET/CT: Highly sensitive imaging of prostate cancer using Ga-68 or F-18 tracers for early recurrence detection.
- DOTATATE PET/CT: Most sensitive scan for neuroendocrine tumours (NETs) and selection for PRRT therapy.
- FDG PET/CT: Widely used glucose analogue scan for lymphoma, lung cancer, infection, and inflammation.
- Cardiac nuclear imaging: Evaluates blood flow (MPI), viability, and MUGA (heart function) for coronary disease assessment.
- Brain PET imaging: Detects Amyloid plaques and Tau tangles for early dementia and Parkinson's diagnosis.
- F-18 FDG (Glucose metabolism): Most cancers, infection, inflammation
- Ga-68 PSMA (PSMA receptor): Prostate cancer staging and recurrence
- Ga-68 DOTATATE (Somatostatin receptor): Neuroendocrine tumours
- F-18 NaF & Tc-99m MDP (Bone turnover): Metastases, fractures, Paget's disease
- Tc-99m Sestamibi (Perfusion): Cardiac stress test, parathyroid imaging
- Tc-99m DTPA (Renal function): GFR evaluation
- Tc-99m HIDA (Liver function): Biliary leakage, system evaluation
- Tc-99m Sulphur colloid (Lymphatic system): Sentinel lymph node evaluation
- F-18 Florbetapir (Amyloid plaques): Alzheimer's diagnosis
- I-123 MIBG (Adrenergic tissue): Phaeochromocytoma, paraganglioma
- F-18 FDOPA (Dopamine synthesis): Brain tumours, NETs, movement disorders
- Oncology: Lung, Lymphoma, Prostate, Breast, thyroid, Colorectal cancer staging and response surveillance.
- Neurology: Alzheimer's, Parkinson's disease, Epilepsy focus localisation, and Brain tumour grading.
- Cardiology: Coronary artery disease MPI, Heart failure viability, and MUGA cardiotoxicity monitoring.
- Specialties: Hyperparathyroidism, Pulmonary embolism (V/Q scan), Fever of unknown origin, and Renal function evaluation.
Equipment & Technology
GE Hawkeye Gamma Camera
Advanced dual-head gamma camera with SPECT capability for high-quality nuclear imaging of all organs.
GE NM 630 Discovery Machine
State-of-the-art nuclear medicine imaging system for precise diagnostic scans.
Gamma Spectroscopy Machine
Analyzes energy spectrum of gamma radiation for quality control and radiopharmaceutical purity testing.
ITLC Gamma Analyser
Instant Thin Layer Chromatography system for radiopharmaceutical quality assurance.
Multiple Laser X-ray Film Printers
High-quality medical image printing systems for producing diagnostic-grade hard copies of nuclear medicine scans.
Gamma Probe Machine
Intraoperative radiation detection device used during sentinel lymph node biopsy and tumor localization surgery.
High Dose Therapy Ward
Dedicated isolation facility with proper radiation shielding for radioiodine therapy and other therapeutic nuclear medicine procedures.
Two-Bedded Therapy Ward
Comfortable patient rooms equipped with all necessary amenities and radiation safety features.
Fume Hood in Therapy Ward
Ventilated enclosure for safe handling of radioactive materials in patient care areas.
Dose Calibrator Machine
Precisely measures radioactivity of radiopharmaceuticals before administration to ensure accurate patient dosing.
Hand and Foot Radiation Monitor
Detects radioactive contamination on hands and feet of staff and patients for safety compliance.
Pocket Dosimeter
Personal radiation monitoring device worn by staff to track individual radiation exposure levels.
Multiple LED L-Bench (Fume Hood)
Laminar flow workstations with LED lighting for safe handling and preparation of radiopharmaceuticals.
Contamination Monitor
Detects and measures radioactive contamination on surfaces and equipment.
Area Radiation Monitor
Continuously monitors ambient radiation levels in the department to ensure staff and patient safety.
Lead-Lined Waste Bin
Shielded containers for safe disposal of radioactive waste materials.
Our Experts
Dr. Krishna Kumar R
Professor Nuclear Medicine & Radiation Oncology
Dr. Ashok Kumar R
Consultant Nuclear Medicine
Dr. G. K. Rangarajan
Scientist D & Radiation Safety Officer - Nuclear Medicine (HDT)
Mrs. N. Anandi
Technologist
Mr. K. Ramesh
Staff Assistant
Legacy & History
Key Achievements
- Established in November 1957 - One of India's first nuclear medicine pioneering departments.
- Pioneered use of radioactive iodine and gold years before national isotope supply began (1961).
- Key influencer for the Atomic Energy Establishment's Isotope Division in Trombay.
- Research Excellence: Groundbreaking metabolic pathway studies by founder Dr. V.M. Sivaramakrishnan.
- Training & Education: Currently training 23 students across Intern programs (2025/2026) and three years of Nuclear Medicine Technology.
- Academic Impact: Total of 12 major publications and conducting M.Sc. Medical Physics classes.
- Patient Care: Treated thousands of cancer patients over 65+ years of continuous service.
Support Groups
Content is yet to be provided
Refer a Patient
Our imaging services are available upon referral from treating physicians
nuclearmedicine@cancerinstituteadyar.org