| FLAIR | T2 with inversion pulse nulling CSF | CSF dark, oedema bright | MS periventricular plaques, cortical/juxtaventricular lesions, SAH (sulcal hyperintensity), meningitis (post‑contrast FLAIR) |
| STIR | inversion nulling fat (non‑selective) | fat dark, fluid bright | marrow oedema, occult fractures, osteomyelitis, metastases |
| Chemical fat saturation | spectral fat suppression | fat dark | post‑Gd T1 FS (enhancement in fatty areas), MSK |
| DWI | sensitivity to random (Brownian) water motion | restricted diffusion = bright | acute infarct (minutes), abscess (pus), epidermoid, hypercellular tumours (lymphoma, medulloblastoma), CJD, DAI |
| ADC map | quantitative diffusion | true restriction = dark | separates restriction from T2 shine‑through (bright on both DWI and ADC) |
| *GRE T2 / SWI** | susceptibility | haemosiderin, deoxyHb, calcium, iron = dark blooming | microbleeds (amyloid, hypertension), DAI, cavernoma, haemorrhagic transformation, venous thrombosis |
| MRA | TOF (flow‑related enhancement) or contrast‑enhanced | bright vessels | aneurysm, stenosis, AVM; TOF needs no contrast |
| MRV | venous TOF / phase contrast / CE | bright sinuses | cerebral venous thrombosis |
| MRCP | heavily T2W | static fluid (bile, pancreatic juice) bright | CBD stones, strictures, choledochal cyst, pancreas divisum |
| MRS | chemical spectrum | peaks: NAA (neurons), choline (membrane turnover), creatine, lactate, lipid, alanine | tumour ↑choline ↓NAA; abscess: amino acids, acetate, succinate; meningioma alanine; Canavan ↑↑NAA |
| Perfusion (DSC/ASL) | bolus or labelled blood | rCBV maps | tumour grade, recurrence vs radiation necrosis, stroke penumbra |
| Dynamic contrast | serial T1 after Gd | enhancement curves | pituitary microadenoma, breast, prostate |