Sequence Overview
Sequence Type: 3D Black-Blood Turbo Spin Echo (BB-TSE)

Field Strength: 1.5T / 3.0T (SAR-optimized for 3T)

Primary Applications:

Intracranial/Carotid Vessel Wall Imaging

Atherosclerotic Plaque Characterization

Vasculitis Assessment

Key Parameters
1. Pulse Timing
Parameter Settings Clinical Relevance
TR 1200-1500 ms (3T: 1000-1300 ms) Balances T2 contrast & scan efficiency
TE 40-50 ms Optimizes wall-lumen contrast
Echo Train Length (ETL) 24-32 Reduces scan time
Inversion Times (TI) Dual IR: TI1=450 ms (blood nulling), TI2=150 ms (fat suppression) Blood signal suppression + fat saturation
2. Spatial Encoding
Matrix: 320×256 (reconstructed to 512×512)

Voxel Size: 0.6×0.6×1.0 mm³ (isotropic 0.8 mm optional)

FOV: 200×200 mm (adjustable for carotid/brain)

3. Advanced Features
Motion Suppression:

Double Inversion Recovery (DIR): Blood signal nulling

ECG Triggering (optional): Cardiac motion compensation

CSF Flow Compensation: Reduces pulsation artifacts

Acceleration:

Compressed SENSE: 3× faster scans (5 min full-brain vessel wall)

Partial Fourier: 5/8 phase sampling

Clinical Protocol Examples
1. Carotid Artery Plaque Imaging
Recommended Settings:

TR/TE = 1300/45 ms, TI = 450/150 ms

0.6 mm isotropic, ETL = 28

Scan Time: 6 min 20 sec

Key Features:

Fibrous cap integrity assessment

Intraplaque hemorrhage detection

2. Intracranial Vasculitis
Recommended Settings:

TR/TE = 1500/50 ms, TI = 500/150 ms

0.8 mm isotropic, multi-slab acquisition

Scan Time: 7 min 15 sec

Performance Metrics
Vessel Wall SNR: ≥20 dB (3T)

Lumen-Wall CNR: ≥3.8

Blood Suppression Efficiency: >98%

Technologist Notes
1. Protocol Optimization
For 3T: Reduce TI1 to 400 ms if blood nulling is incomplete

Metal Implants: Enable MARS-V (Metal Artifact Reduction Software)

2. Troubleshooting
Ghosting Artifacts: Increase phase oversampling +30%

Poor Fat Suppression: Use spectral fat saturation as backup

3. Contraindications
Avoid for: Patients with irregular heart rhythms (if ECG-gated)