Nuclear medicine for neuropsychiatric and endocrine diseases

Question 1

Methods of functional brain mapping

What other funciton can these tracers have?

Answer 1

fMRI - BOLD imaging

regtional cerebral blood flow SPECT, rcbf SPECT
- using diffusible radiotracers: Hexamethylproplyeneamineoxime HMPAO, or EthylCysteinateDimer. ECD.

These tracers diffuse out and become trapped, increased trapping, increased flow.

FDG glucose is also useable and is proportional to the regional glucose metabolism.

To map vascular lesions and show areas of decreased perfusion.

To locate Epileptic Foci.

For REceptor scintigraphy to image loss of SN Dopaminergic neurons. in Parkinsons disease and differentiate it from essential tremor, using ligands to the DAT transporter.

Diagnosing brain death.

Question 2

What brain disease is SPECT useful for the early diagnosis of

Answer 2

posterior parietotemporal areas, hippocampal areas.

distinguishes AD from Frontotemporal dementia, where these regions are more affected.

Question 3

How is nuclear medicine used for endocrine diseases

Answer 3

Radioiodine to locate toxic goiter nodules, and to locate possible thyroid cancer metastases

MIBG labeled ligands (containing labeled iodine) for the adrenal receptor to locate pheochromocytomas and neuroblastomas
Neuroectodermal tumors are rich in adrenergic receptors - children neuroblastomas
Pheochromocytomas in adults.

Octreotide scan. Labeled somatostatin receptor ligand. 
To locate:
- carcinoid tumors
- pancreatic neuroendocrine tumors
- meningiomas