CISS sequence (MRI)

Last edit by Alaric Steinmetz on

Synonyms: Constructive interference in steady state sequence

The CISS (Constructive interference in steady state) sequence is a gradient echo MRI sequence, which offers the advantage of a high signal-to-noise ratio, a high contrast-to-noise ratio, and an intrinsic insensitivity to movements[^1].

Usage

The image contrast in a CISS sequence is determined by the ratio of T2/T1 tissue and thus provides excellent contrast in intracranial imaging between cerebrospinal fluid and other structures. Due to this property, the CISS sequence is used to depict structures surrounded by cerebrospinal fluid[^1].

Imaging

Illustration of an MRI CISS sequence
Illustration of an axial MRI CISS sequence showing the cerebellopontine angle.
Aqueductal stenosis on sagittal MRI
Illustration of an aqueductal stenosis in an MRI CISS sequence.
Pineal cyst MRI CISS Sequenz
Sagittal MRI CISS sequence of a patient with a pineal cyst.