physics

MRI/FMRI/diffusion MRI

Type; diagnostic

Radiation; none

Energy; radio, frequency, pulses, and magnetic moment

Dimension; 3-D

Definition; uses magnetic field to image soft tissues

FMRI; brain activity example blood flow

Diffusion, MRI; water movement example strokes, brain tracts

Nuclear medicine

Type; diagnostic

Radiation; yes

Definition; uses injected radioactive Tracers to image organ function

Planar scintigraphy

Type diagnostic

Radiation yes (99m Tc common)

Dimension 2-D

Definition basic nuclear image producing flat images

Bone scintigraphy

Type diagnostic

Radiation yes (99m Tc-MDP)

Dimension 2-D

Definition, detects, bone, metastasis, and fractures

Hepatobiliary scintigraphy

Type diagnostic

Radiation yes(99MTC agents)

Dimension 2-D

Definition evaluate liver and gallbladder function

V/Q lung scan

Diagnostic

Radiation yes ventilation equals radioactive gas, perfusion equals 99M TC-MAA

2d

Detect pulmonary embolism

SPECT single photo emission CT

Diagnostic

Radiation: yes(99M TC,67 GA)

3-D

Rotating gamma camera

PET positron emission tomography

Diagnostic

Radiation: yes (18 FDG)

3-D

Shows metabolic activity(cancer brain)

Radiopharmaceutical

Therapeutic

Radiation yes

Sources: internal isotopes

Definition: radiation source placed inside body near tumour

External beam radiation therapy

Therapeutic

Radiation yes cobalt 60 and linear accelerators

3-D targeting

Radiation directed a tumour from outside

Stereotactic radio surgery

Therapeutic

Radiation: yes

Definition: highly precise radiation in brain, tumors, or lesion

CT (computed tomography)

Diagnostic

Radiation: no radioactive Tracers, but x-rays(hard x-rays)

Dimension 3-D

Definition, cross-sectional imaging using x-rays

Mammography

Diagnostic

Radiation: no tracers, but soft x-rays

Dimension: 2D

Definition: breast imaging for cancer screening

fluoroscopy

Diagnostic

Radiation: no tracers, but x-rays

Dimension: 2D real time

Definition: live imaging

Ultrasound

Diagnostic

No radiation

Dimension: 2-D sometimes 3-D

Definition: uses soundwaves to image organs and fetus

radioactive tracer used in nuclear medicine

• ⁸FDG (Fluorodeoxyglucose) → used in PET scans (glucose metabolism, cancer detection)

• ⁹⁹ᵐTc (Technetium-99m) compounds:

  • ⁹⁹ᵐTc-MDP → Bone scintigraphy

  • ⁹⁹ᵐTc-MAA → V/Q lung scan (perfusion)

  • ⁹⁹ᵐTc-lidocaine → less common, cardiac/liver imaging variants

• ¹³¹I (Iodine-131) → Therapy (Tx) for thyroid disease (also some imaging)

⁶⁷Ga (Gallium-67) → infection/tumor imaging (older nuclear scans)

Radiation therapy sources

⁶⁰Co (Cobalt-60) → External beam radiation therapy