Common sequence roles
T1-weighted imaging often provides anatomical detail; T2-weighted imaging highlights fluid-sensitive contrast; FLAIR suppresses free-fluid signal and is common in brain imaging; DWI and ADC characterize diffusion; perfusion estimates dynamic blood-flow-related information; and MRE estimates tissue stiffness.
Names are not enough
The same sequence family can vary by vendor, field strength, orientation, resolution, timing parameters, contrast use and reconstruction. Series classification therefore combines DICOM acquisition metadata with geometry and review rather than relying only on a label such as T2.
- Confirm that sequences belong to the same patient and examination window
- Record field strength, vendor, model and key acquisition parameters
- Keep derived maps linked to the source acquisition
- Define how missing, repeated and motion-degraded series are handled
Completeness is task-dependent
A FLAIR-only cohort may be valid for one task and unusable for another. The buyer should state which sequence combinations are mandatory and whether the model can accept missing modalities. Completeness is reported per study, not inferred from overall series counts.
Questions, answered directly.
Are T1 and T2 camera settings?+
That analogy is useful for beginners, but technically they are different contrast weightings produced through acquisition parameters and tissue relaxation properties.
Is ADC a separate acquisition?+
ADC is typically a derived map calculated from diffusion-weighted imaging and must remain linked to its source diffusion series.
Does every MRI study include every sequence?+
No. Protocols vary by anatomy, clinical question, hospital, scanner and time period.