1. Nuclear medicine
Basic principles

2. Nuclear Medicine Imaging
 - rays

3. The Nuclear Medicine Department
Imaging rooms
Gamma cameras
Radiopharmacy
Hot Lab
Dose calibrators
Generators
Waste storage areas
Reading room

4. What is Radioactivity? Emitted energy from the nucleus of an atom
“U”nstable,
“D”ecays by
“E”mitting
“B”etas,
“A”lphas, and
“G”ammas

5. Concept of Activity rate of decay.
Radioactivity measured in Curies (Ci)
1 Ci = 3.7 x 1010 disintegrations per second
Also measured in Becquerels (Bq)
1 Bq = 1 disintegration per second

6. Concept of Half-Life (T1/2)
Physical half life (Tp): the time necessary for a radionuclide to be reduced to half of it existing activity. Charachterstic value for each radionuclide .
Biological half life (Tb): time is taken to eliminate half of administrated chemical by biological transport or elimination from specific site (elimination from body with urine).
effective half life (Te) : incoperates both physical and biological
T 1/2 e =
T 1 p X T b / T p + T b

7. Mo-99 / Tc-99m Generator Evacuated Vial Sodium pertecnetate (Na TcO4)
Saline Charge
Alumina Column
99Mo (1-16Ci)
(67 hrs half life)
M99 give Tc99m + Beta particles (B absorbed by generator shielding)
Tc99m give Tc99 + Gamma ray
Direction of Saline Flow

8. Radiopharmaceuticals
Technetium -99m
Non particulate emission
6 hrs physical half life
Predominate (98%)
140 KeV photon energy
Small amount of internal conversion (10%)
Low toxicity

9. Radiopharmaceuticals
After IV injection :
Tc 99m concentrate in salivary gland , choroid plexus ,thyroid gland and gastric mucosa .
Excretion by GI and renal routes .

10. Gamma Cameras
Dual head

11. Four Main Collimator Types
Parallel hole
Low Energy
Medium Energy
High Energy
Diverging hole
Converging hole
Pinhole
Multi-Energy

12. Scintillation Detectors
Light
Gamma Ray
NaI crystal
Thalium activated sodium iodine

13. Photo-multiplier Tube (PMT)
Light into Electricity

14. Bone scan ( whole body bone scan )
Indications :
Detection/Staging of Metastatic bone disease
Benign bone disease
Primary neoplasm
Infectious processes
Joint diseases
Avascular bone disease
Osteoporosis
Trauma; Stress fractures, scaphoid fracture
Metabolic disorders
Pain with normal x ray

15. Pt prepration No special preparation
Hydrate patient as much as possible and void frequently to reduce dose and background.
Ask pt to empty bladder before the scan immediately .
Remove any metallic object from all over the body.

16. Radiopharmaceuticals
Tc-99m – MDP or HDP
Adult dosage: 20-25mCi
Route of administration IV
Delay time post injection 2-3 hrs
Camera
any, dual heads are recommended for WB
Collimators
LEAP
LEHR
Peak 140 kv
Window 15%
Views : Anterior and posterior for whole bone .

17. Normal 99mTc-MDP Bone Scan

18. Metastatic

19. 3- phase bone scan
Mainly to determine osteomylities versus cellulities .
Also primary bone tumor and stresss fracture
Specifec area of skeleton imaged :
1- blood flow (vascularity)for 1-2 min.
2- blood pool immediate post perfusion to 5 min
3- delayed image phase .after 2 hrs

20. 3- phased bone scan Peak at Tc 99m , 15% window LEAP collimators
Immediate after IV injection
Frame time : frame per 10 sec for 5 min.
Delayed imaged
2-3 hrs post injection whole or limited bone scan .

21. 3- phase bone scan
Blood pool
Delay image