42. Nuclear medicine methods in childhood (kidney, bone, 123I-MIBG scintigraphy).

Radiation in children
- Important to weigh risk against benefits when exposing children to radiation
- Appropriate radiation doses for children are calculated by body weight
- Sufficient hydration improves image quality and decreases radioactivity affecting the patient
Important nuclear medicine methods in children
- Renal imaging
  - Renal scintigraphy
    - Static method
    - 99mTc-DMSA
    - Measures corticol loss
    - Indications
      - Congenital renal diseases
      - Pyelonephritis
      - Obstructive renal disease
  - Camera-renography
    - Dynamic method
    - Images before and after furosemide
      - If furosemide improves excretion the obstruction is anatomical
      - If it doesn’t then it’s a functional problem of the kidney
    - 99mTc-DTPA – for glomerular secretion
    - 99mTc-MAG3 – for tubular secretion
    - Creates a time-activity curve = renogram with 3 phases
      - Phase I – perfusion
      - Phase II – filtration or secretion function
      - Phase III – excretion function
    - Indications
      - Obstructive renal disease
      - Reflux disease
- Bone scintigraphy
  - 99mTc-MDP (diphosphate)
  - Can be difficult to evaluate due to high activity of the epiphyses
  - Indications
    - Inflammations
    - Bone tumors
    - Osteonecrosis
    - Fractures
- I123-MIBG scintigraphy
  - I123-MIBG binds to adrenergic receptors in neuroendocrine tumors
  - Indications
    - Neuroblastoma
    - Phaeochromocytoma
  - Thyroid must be protected from radiation
    - Iodine is given before examination