Nuclear Medicine and nuclear power plants (for generating electricity) exemplify the most spectacular, peaceful applications of nuclear energy. Thanks to the vision of Homi Bhabha and Jawaharlal Nehru, India entered the nuclear age without any time lag with the rest of the advanced world.
The regular supply of reactor produced radiopharmaceuticals and radioimmunoassay kits from BRIT (a part of BARC) have been a major factor in the development of nuclear medicine in India. Unfortunately the biggest obstacle has been the lack of imaging equipment at an affordable price. The vision reflected in the field of indigenous manufacture of gamma cameras and computers, which are very essential if the benefits of nuclear medicine have to reach patients at the 500 district level hospitals in the country.
The performance of China has been much better than us in this regard. In an article in the Indian Journal of Nuclear Medicine (January 1990), I had described an action plan for procurement of equipment submitted to the then chairman of the Atomic Energy Commission, which did not take off. As an inveterate optimist, I will again try to persuade the new chairman of AEC, hoping for better luck this time!
Changing face of Nuclear Medicine
I am perhaps the only living member of the Indian Society of Nuclear Medicine who continues to be active from its inception in 1968 to date. The papers I presented over the years reflect the changing emphasis of nuclear medicine in India (Table I). My, book "Principles and Practice of Nuclear Medicine published in 1984 with foreword by Dr. Henry Winger fully reflects the experience of a decade gained at the Jaslok Hospital & Research Centre, covering the full spectrum of nuclear medicine in India
Today nuclear medicine has to seek its proper role in the evaluation of patients in a highly competitive environment, vis a vis, other imaging modalities- radiology, ultrasonography, CT and MRI. Nuclear Medicine tests will survive by virtue of their ability to give unique and incremental information in a cost-effective manner. In view of its total non invasiveness and portability, untrasonography is the modality of first choice in an increasing number of clinical problems and it is my own philosophy that whatever can be done well with ultrasonography need not be done by nuclear medicine unless nuclear medicine provides unique or incremental information sought by the clinician, but not provided by ultrasonography. Thus in the 1960''s we used nuclear medicine to detect placenta previa and pericardial effusion, but cheerfully gave way to ultrasonography when it became available. Between 1974 and 1979 radio nuclide brain scanning was a major activity at Jaslok hospital. As soon as CT became available I anticipated its impact on brain imaging and shifted focus to nuclear cardiology in 1979.
Currently ECG gated SPECT myocardial perfusion imaging, which gives information about perfusion imaging, which gives information about perfusion, wall motion and thickening as well as rest LVEF, serves as a "gate keeper" for the evaluation of patients with suspected or proved Coronary artery disease as well as for management decisions based on risk stratification. If and when 2D echocardiography with contrast agents starts doing this well and at an affordable cost (which in my judgement is 10 years away) the nuclear medicine departments will be doing metabolic and receptor imaging of the heart. These along with hypoxia, infarction and apoptosis imaging will continue to provide enough scope for nuclear medicine even in competition with Cardiac MRI and MRS. In my view bone and joints, liver-spleen and kidney imaging will continue to be the staple sources of nuclear medicine studies but imaging cancer will occupy centre stage.
Awareness about Nuclear Medicine
In an Editorial in January 6,2000 issue of the New England Journal of Medicine, entitled "Looking Back on the Millennium in Medicine" there is a section on Development of Body Imaging, Which only makes a passing reference to radio nuclide Tracers. While it mentions the contribution of CT and MRI, which permits resolution of very small structures throughout the body, it fails to mention PET and the unique contribution of metabolic imaging exemplified by FDG and receptor imaging exemplified by GDG and receptor imaging now available thorough PET and SPECT. No wonder Dr. Henry Wagner has been saying that the capabilities of nuclear medicine are well-guarded secrets!
The Indian scene is relatively better. The nuclear medicine community in India has fully utilized all medical platforms and continuing medical education programmes (Indian Medical Association, Association of Physicians of India, Cardiological Society of India etc) to emphasize the unique role of nuclear medicine in all aspects of clinical management of patients - diagnosis, prognosis. Radio iodine therapy for Graves'' disease and thyroid cancer, palliative use of Strontium - 87 and P 32 in painful bone metastases are now routine in most centres and radio nuclide synovectomy is a new addition to radio nuclide therapy. The Text Book of Medicine published by Association of Physicians of India has sections on nuclear medicine and nuclear cardiology. Unfortunately most of the 150 medical colleges in India have no facilities for nuclear medicine.
Thrust areas for future
Necessity is the mother of invention. The lack of availability of FDG for metabolic imaging of cancer should encourage the use of alternative and available and affordable strategies. I have described Tc-99m glucoheptonate as the "Poor man''s FDG" I am happy to note that at least 3 nuclear medicine centres in the country have established the validity of this approach. We should also put infection imaging, exemplified by Tc -99m labelled ciprofloxacin on a fast track. I would like to see the routine use of Tc 99m labelled leukocytes and Tc - 99m human immuno globulin as useful agents for imaging infection and inflammation. My favourite project of radioimmuno scintigraphy of tuberculous lesions (especially brain tuberculoma, hilar and abdominal and pelvic lymph nodes, bone and joint tuberculosis) is not making progress due to lack of availability of a suitable monoclonal antibody of the IgG class in large quantities (1 mg of fab fragments per patient), but efforts are ongoing.
The first ever Cyclotron and PET facility in India will be functioning at the RMC early next year. The ya committee (of which I was a member) had recommended a 10 -19 Mev Cyclotron capable of producing I - 123 in addition to the usual C - 11, N - 13, O - 15 & F - 18. I had emphasized the importance of I 123 based radio pharmaceuticals for SPECT (editorial IJNM 1996- Cyclotrons in India- MIBG and I-123 BMIPP are of particular clinical interest. It will be a great disappointment if the cyclotron at RMC does not produce I-123 for clinical use.
The Future
Unlike USA Where nuclear medicine is dominated by radiology nuclear medicine is practiced in India as an independent autonomous specialty, as advocated by Dr. Henry Wagner. In my own experience and observations, Young men and women who have entered nuclear medicine with adequate clinical experience (such as MD in internal medicine) have excelled since they have and adequate exposure to clinical problem solving tasks including the use and interpretation of radiology, ultrasonography, CT and MRI in the work place. A nuclear medicine physician with a good clinical background can confidently relate to other specialties on an equal footing - cardiologists, neurologists and psychiatrists, endocrinologists, gastroenterologists and hepatologists, Nephrologists and urologists and rheumatologists and orthopaedic surgeons, haematologists and oncologists, etc especially since progress in nuclear medicine in occurring at the advancing edge of knowledge in all these fields. There is no place for mediocrity in a highly competitive environment where noting but the best is going to be good enough for our survival and advancement.