DIAGNOSTIC $ THERAPEUTIC NUCLEAR MEDICINE.

Presented at the KNH Research SymposiumOn 13th April 2012

PRESENTER:

DR. DAVID NDIRANGU THEURI

Nuclear medicine Physician I/C, Nuclear Medicine Unit, Cancer Treatment Centre, Kenyatta National Hospital

DIAGNOSTIC $ THERAPEUTIC NUCLEAR MEDICINE.

WHAT IS NUCLEAR MEDICINE?

It is the branch of medicine that utilises nuclear technology for the diagnosis and treatment of diseases.

PRINCIPLE OF NUCLEAR MEDICINE.

It uses the principle that a certain radiopharmaceutical (tracer) will at a certain point in time have a preferential uptake by a particular body or tissue.

This uptake is then imaged by the use of detectors mounted in gamma cameras or PET (positron emission tomography) devices.

ADVANTAGES OF NUCLEAR MEDICINE

Ability to image the whole body in a single sitting at a comparably short time hence increased patient through fare.

Minimal radiation burden to patients, personnel and environment- the dosages used are very small

Non-invasiveAble to give information on cellular activity at

an early stage.

DISADVANTAGES

Uses very costly and sophisticated equipment.

Requires highly trained personnel.

Higher chances of radiation exposure since the source is unsealed.

Radiation accidents are more likely to occur if safety precautions are compromised.

WHAT IS PECULIAR ABOUT NUCLEAR MEDICINE?

Unlike other radiation applications for medical use, nuclear medicine uses unsealed sources of radiation. The tracer is introduced into the body of the patient through several routes (oral, intravenous, percutaneous, intradermally or inhalation) and he/she becomes the source of radiation.

This radiation can then be detected (for diagnostic use) or used to kill some selected unwanted body cells (therapeutic use).

TYPES OF DIAGNOSTIC PROCEDURES DONE AT KNH

1.Whole body radionuclide bone scan

-To detect skeletal metastases from cancers such as breast, lung, colon, thyroid, prostate.

-To detect the skeleton as the primary source of cancer.

-to detect inflammatory conditions of the connective tissue including infections.

cont…

-to detect degenerative joint diseases such as osteoarthritis.

-to detect sport injuries such as stress fractures

-to determine whether pain from a joint prosthesis is due to loosening or infection.

-to detect areas of ectopic calcification

Cont…

2.Radionuclide thyroid scan - To determine the anatomical position of the

thyroid gland -To determine the functional status of the

thyroid gland i.e hypo or hyper thyroidism -To determine possibility of cancer of the

thyroid gland (“cold’’ areas)- To determine outcome of radioiodine therapy

Cont…

3.Renal scans -Renogram :will delineate the function of

each kidney and the associated collecting system to provide the so-called split kidney function

-Renal perfusion studies :eg after kidney transplant

-Renal function :glomerular filtration rate (GFR)

-Renal anatomy :e.g. ectopic kidneys

Cont…

4.Myocardial perfusion imaging :(MPI)

-For diagnosis of coronary artery disease (CAD) -To differentiate between viable and non-viable

myocardial tissue e.g. after a myocardial infarction (MI) hence deciding on mode of therapy (surgery vs. medical intervention)

-surveillance for those patients known to be at risk of developing CAD eg diabetes

Cont…

5. Lung perfusion studies :to detect pulmonary

embolism.6. Adrenocortical imaging :to detect

pheochromocytoma7. Brain perfusion studies :to detect

epileptic foci, dementias, infarction, Parkinsonism.

Cont…

8. Sentinel lymph node (SLN) mapping and lymphoscintigraphy :especially in breast cancer and melanoma. Will help in determining whether lymphoedema is primary ( congenital ) or secondary ( obstructive ).

9. Hepatobiliary (HIDA) Scan: to determine the anatomical and functional integrity of the liver and the biliary ducts; this scan is of great help in differentiating between biliary atresia (whose management is surgical) and other forms of neonatal jaundice (medical management).

2611 patients have undergone diagnostic nuclear medicine studies up to date ( 10 th March 2012 ) as follows;TYPE OF

PROCEDURE

NO OF CASES

  Year 2006 & 2007

Year 2008

Year 2009

Year 2010

Year 2011

Year 2012

Totals

RADIONUCLIDE BONE SCANS

112 101

125 652

521

247

1756

THYROID SCANS 62 86 101 223

125

25 622

RENAL SCANS 14 3 6 64 41 17 145

LUNG PERFUSION SCANS

16 2 _ 2 0 0 20

LYMPHOSCINTIGRAPHY

7 4 2 15 17 0 47

LIVER (HIDA) SCANS

_ _ 1 8 1 0 10

MYOCARDIAL PERFUSION IMAGING (MPI)

- - - 8 0 o 8

MECKLE’S DIVERTICULITIS

0 0 0 0 1 0 1

MIBI PARATHYROID SCANS

0 0 0 1 1 0 2

Totals 211 196

235 973

707

289

2611

Therapeutic radiopharmaceuticalsTherapeutic radiopharmaceuticals

Non-specificNon-specificSr-89, Sm-153, Re-189Sr-89, Sm-153, Re-189Bone pain palliationBone pain palliation

SpecificSpecificI-131I-131

Thyroid cancer, as specific Thyroid cancer, as specific diagnostic if tumor significantly diagnostic if tumor significantly accumulatesaccumulates

Y-90Y-90Zevalin – monoclonal antibody for Zevalin – monoclonal antibody for B-cell lymphomasB-cell lymphomas

CHALLENGES

Delays in procurement of radiopharmaceuticals e.g 99m-Tc generators and radio-iodine from south Africa

Lack of adequate awareness of the existing NM facilities by our colleagues and the public.

Inadequate numbers of trained personnel and equipment

Lack of PET device and PET/CT hybrid devices for image fusion due to the costs involved

Global shortage of Molybdenum -99.

ACKNOWLEDGEMENTS

IAEA & KNH administration for their supportive roles in making nuclear medicine in this country a reality.

T H A N K Y O U.