Image Compression and Study Size

Ultrasound

Ultrasound study size is primarily affected by:

• Number and duration of cine clips
• For Cardiac, number of cardiac cycles captured per clip 
• Frame rate and image dimensions
• Compression method and settings
• Number of still images and clips acquired

When clinically appropriate, acquire the minimum number and duration of clips necessary to adequately document the examination. Avoid unnecessarily long or duplicate cine loops.

For routine rhythm, fewer cardiac cycles per clip can substantially reduce study size. Additional cycles may be necessary for arrhythmias, respiratory variation, contrast imaging, or other clinical circumstances.

DICOM supports multiple lossless and lossy compression methods for ultrasound images. There is no single compression ratio appropriate for every modality or examination. Compression settings should preserve the image quality necessary for diagnostic interpretation.

Still images generally contribute much less to total study size than cine clips; therefore, optimizing cine acquisition usually provides the greatest reduction in study size.

XA – Fluoroscopy and Cineangiography

XA study size is primarily affected by:

• Image matrix/resolution
• Number of frames acquired
• Frame rate and acquisition duration
• Compression settings

For example, a 512 × 512 image contains one-quarter the pixels of a 1024 × 1024 image. Resolution and compression should be configured to meet the clinical requirements of the examination.

Key Recommendation