Table 3.

The imaging configurations and main clinical distinctions of T₁w, T₂w, ceT₁w, and FLAIR.

Sequence	Sequence Characteristics	Main Clinical Distinctions	Example *
T1w	Uses short TR and TE [64]	Lower signal for a higher water content [66], such as in edema, tumor, inflammation, infection, or chronic hemorrhage [66] Higher signal for fat [66] Higher signal for subacute hemorrhage [66]
T2w	Uses long TR and TE [64]	Higher signal for a higher water content, such as in edema, tumor, infarction, inflammation, infection, or subdural collection [66] Lower signal for fat [66] Lower signal for fibrous tissue [66]
ceT1w	Uses the same TR and TE as T1w; employs contrast agents [64]	Higher signal for areas of breakdown in the blood–brain barrier that indicate induced inflammation [65]
FLAIR	Uses very long TR and TE; the inversion time nulls the signal from fluid [67]	Highest signal for abnormalities [65] Highest signal for gray matter [67] Lower signal for cerebrospinal fluid [67]

* Pictures from [68]. TR, repetition time. TE, echo time.