MRS

Question 2

MR spec - NAA

Answer 2

Neuronal integrity marker Decreases with tumor, stroke, epilepsy

Question 3

MR spec - creatine

Answer 3

Energy source, most stable peak Increased in hypo-metabolic states Decreased in hyper-metabolic states

Question 4

MR spec - choline

Answer 4

Precursor of Ach Increased from increased cell proliferation or increased number of cells (tumors)

Question 5

MR spec - lactate

Answer 5

Metabolic - if present, think badness Necrosis from infection or high grade tumor

Question 6

MR spec - characteristics seen with malignancy

Answer 6

Decreased NAA as it destroys neurons, and creatine as it depletes energy stores Increased choline (cell turnover), lactate (necrosis from outgrowing blood supply), and lipid (d/t necrotic center in higher grade neoplasms)

Question 7

MR spec characteristics of GBM/mets

Answer 7

+choline, - NAA, - creatine, +++lactate

Question 8

MR spec characteristics of abscesses

Answer 8

absent choline, absent NAA, absent creatine, +++lactate