Ga-67

General

  • Binds to plasma proteins (basically acute phase reactants) like lactoferrin and transferrin which localize to areas of inflammation

  • T1/2 = 78 hours

  • Energy = 93, 185, 288, 394 keV

  • Better in evaluation of spinal infection than other studies

  • Emits gamma rays

  • Uptake in lacrimal glands is how you will know the study is done with Ga-67

  • Uses -

    • Fever of unknown origin

    • Sarcoid & TB

      • Panda sign to show sarcoid

    • Evaluation of spinal infection/osteomyelitis

    • Evaluation of pulmonary infection and/or inflammation —-> PCP

    • Diagnosis and follow up evaluation of retroperitoneal fibrosis

    • Evaluation of drug induced pulmonary toxicity/fibrosis (i.e. bleomycin, amiodarone use)

Sarcoid

  • Panda sign

Interstitial Lung Disease

  • Grade 1 - < background < bone

  • Grade 2 - = bone (pic is grade 2)

  • Grade 3 - = liver

  • Grade 4 - > liver

References:

Gallium

  • 4 peaks

    • 93 keV

    • 184 keV

    • 300 keV

    • 393 keV

    • Basically 100-200-300-400

  • Half life ~ 3 days

  • Decay by electron capture

    • Things that decay by electron capture = GIIT

    • Gallium, Indium, Iodine 123, Thallium

  • Poor man’s bone scan

  • Normal uptake in

    • Liver

    • Kidneys early, but if see kidney after 24 hours = bad

    • Faint uptake in breasts

    • Lacrimal gland uptake

    • Some faint GI uptake

      • Indium (In-111 WBC scan)is therefore better if looking for abdominal or pelvic infections

  • Malignant otitis media

    • Hot on both Ga & Bone scan

  • Spinal osteomyelitis

    • Ga is better than In for spine infections

  • Buzzwords

    • Ga + AA = sarcoid

    • Ga + AIDS = PCP

    • Ga + Spine = osteomyelitis

    • Ga + faint bilateral breast uptake = normal

    • Ga + intense unilateral breast uptake = bad

  • Ga vs Thallium

    • PCP = Ga hot & Th cold

    • Lymphoma = Ga cold & Th hot

Normal Study

Interstitial Lung Disease

Interstitial Lung Disease