Nuclear Medicine - Copy

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Basic principles

- rays

Imaging rooms Gamma cameras

Radiopharmacy

Hot Lab Dose calibrators

Generators

Waste storage areas

Reading room

Emitted energy from the nucleus of an atom

Nucleus

Unstable,

Decays by

Emitting

Betas,

Alphas, andGammas

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

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

eleminiate half of adminstrasted chemial .

effective half life (Te) : incoperates both

physical and biologicalT 1/2 e =

T 1 p X T b / T p + T b

Direction of Saline Flow

Evacuated VialSodium pertecnetate(Na TcO4)

Alumina Column99Mo (1-16Ci)(67 hrs half life)

Saline Charge

Technetium -99m

Non particulate emission

6 hrs physical half life

Predominate (98%)

140 KeV photon energy

Small amount of internal conversion (10%)

Low toxicity

After IV injection :

Tc 99m concentrate in salivary gland ,

choroid plexus ,thyroid gland and gastric

mucosa . Excretion by GI and renal routes .

Dual head

Parallel holeLow EnergyMedium EnergyHigh Energy

Diverging holeLow Energy

Converging holeLow Energy

PinholeLow EnergyMulti-Energy

Gamma Ray

NaI crystalThalium activated

sodium iodine

Light into Electricity

Indications :

Detection/Staging of Metastatic bone disease

Benign bone disease

Primary neoplasm Infectious processes

Joint diseases

Avascular bone disease

Osteoporosis

Trauma; Stress fractures

Metabolic disorders

Pain with normal x ray

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 .

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

LEHR Peak 140 kv

Window 15%

Views : Anterior and posterior for whole bone .

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

3- delayed image phase .after 2 hrs

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 .

Blood pool

Delay image

Nuclear Medicine - Copy

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