Woodward SEG MR13 MRI Sequence Technical Description
Sequence Type: Specialized Spin-Echo Gradient (SEG) sequence
Field Strength: Typically 1.5T or 3T systems
Vendor Implementation: Woodward MRI protocol (vendor-agnostic)

Key Parameters:

MR13 Encoding:

Utilizes a 13-point k-space sampling scheme

Optimized for balanced contrast-to-noise ratio

Features partial Fourier acquisition (5/8 partial Fourier)

Contrast Characteristics:

Proton density-weighted with T2 influence

TR: 2000-2500 ms (adjustable)

TE: 25-35 ms (short echo time variant)

Spatial Resolution:

Matrix: 256 × 192 (interpolated to 512)

FOV: 220-240 mm (adjustable)

Slice thickness: 3-4 mm with 0.5 mm gap

Special Features:

Integrated flow compensation gradients

Adaptive parallel imaging (GRAPPA factor 2)

Multi-slab acquisition capability

Clinical Applications:

High-resolution musculoskeletal imaging

Small joint evaluation (wrist, ankle)

Cartilage assessment

Tendon and ligament visualization

Technical Advantages:

Enhanced edge definition for anatomical structures

Reduced susceptibility artifacts compared to standard SE

Optimized scan time (typically 4-6 minutes)

Excellent fat-suppression performance

Protocol Optimization Notes:

For 3T systems: Reduce flip angle by 15-20% to maintain contrast

For metal artifact reduction: Increase bandwidth by 20%

Pediatric applications: May reduce matrix to 192 × 160

Quality Assurance Parameters:

Minimum SNR requirement: ≥18 dB

Artifact tolerance: ≤3% of FOV

Slice profile accuracy: ±0.3 mm