PET is a growing diagnostic tools and radiopharmaceuticals are the essential part in diagnosing a disease.

1. Prepared by:
Madan Baral (8)
Anish Shrestha (9)
Krishna Ghimire (10)
Rahul Rana Chhetri (11)
RADIOPHARMACEUTICALS:
POSITRON EMMISION
TOMOGRAPHY (PET)

2. Introduction
ET- Positron Emission Tomography
mployed since 1970
on-invasive method for diagnosis and management of cancer
ields high-quality images that characterize substrate metabolism,
cellular proliferation, receptor density and other parameters used
to identify cancer and evaluate its response to treatment
llows the physician to to retain the cerebral physiology of patient
through the low resolution “autoradiograph”

3. Methodology
adiolabelled tracers injected in nonpharmacologic doses are used
to construct three dimensional images by computer to
demonstrate the location and concentration of the tracer of
interest
uantitative imaging of regional function and chemical reactions
within various organs of the human body
pplication in mapping regional blood flow, oxygen metabolism,
regional blood volume, rates of use of metabolic substrates
receptor-specific tracer binding, bone remodeling , tumor receptor
density, and reporter gene expression

4. Operation

5. Types of Tracer Molecules
arbon-11
itrogen-13
xygen-15

6. Carbon-11
ncorporated into a number of organic molecules like carboxylic
acids, alcohols glucose
alf life is 20 minutes
almitic acid commonly used for myocardial metabolism
pplication: Imaging of cerebral glucose metabolism

7. Nitrogen-13
3
N ammonia used for cerebral and myocardial blood flow
alf life 10 minutes
uperior than radioactive noble gases due to lower solubility in
gases

8. Oxygen-15
5
O has too short half life for tracer synthesis
alf life: 2.04 minutes
vailable radiopharmaceuticals radiolabeled with 15
O are
5
Ooxygen gas(15
OO): Used for the studies of Oxygen
metabolism,
5
O water ( H2
15
O): Used for the equilibrium studies of tissue water
content

9. Fluorine-18
8
F has long half-life 110 minutes comparatively
hows receptor-specific tracer binding
DG(2-18
F-fluoro-deoxy-D-glucose) major application in imaging of
cerebral, myocardial, and tumor metabolism, myocardial and
tumor metabolism
lso cancers of lung and colon and myelomas and lymphomas.

10. Gallium-68
apidly bound to iron-binding sites
pplication: studies of regional plasma volume also in calculation
of regional hematocrit

11. References
oyd V. Allen Nicholas G. Popvich, Howard C. Ansel (2008),
Ansel’s Pharmaceutical Dosage Forms and Drug delivery Systems
(8th
Ed),Walters Klewer ,New Delhi,pp 584-588