“Short answer”
1) MS versus MS versus MS (Mitral stenosis, Multiple sclerosis, Musculoskeletal system)
2) EEG versus EKG/ECG (electroencephalogram, electrocardiogram)

What do these abbreviations stand for? (I put answer for you)

If disease or conditions, tell me what it is, cause(s), symptoms, and prognosis (likely course of the disease). Compare/contrast these terms.

If procedure/test, tell me what it is, what does it test/look for, and difference and or similarities between them. Compare and contrast.

Add extra information about the diseases/conditions or test which you find interesting.

Use proper sentence structure, punctuation and no misspelled words.

Thank you!