GRASP-VIBE vs CAIPIRINHA-VIBE for Pediatric Liver MRI

Managing respiratory motion represents one of the most significant challenges during a pediatric liver MRI. For instance, clinicians historically relied on breath-hold sequences like CAIPIRINHA-VIBE to capture dynamic contrast phases. However, young children often struggle to comply with breathing commands, which frequently leads to severe motion artifacts. Consequently, radiologists often utilize free-breathing techniques such as GRASP-VIBE to bypass this respiratory limitation.

Comparing GRASP-VIBE and CAIPIRINHA-VIBE

A recent retrospective study evaluated seventy children who underwent dynamic liver MRI at 3 Tesla. Specifically, the cohort included forty patients scanned with free-breathing GRASP-VIBE and forty patients scanned with breath-hold CAIPIRINHA-VIBE. Additionally, ten patients underwent both protocols at different clinical time points, allowing for direct comparison. Subsequently, two independent radiologists reviewed four dynamic contrast phases at matched anatomical levels to assess image quality. Ultimately, this rigorous review resulted in six hundred and forty individual image comparisons per reader.

Key Findings in Pediatric Liver MRI Quality

The study demonstrated that radiologists overwhelmingly preferred the free-breathing GRASP-VIBE sequence over CAIPIRINHA-VIBE. For example, readers preferred GRASP-VIBE in eighty-two percent of arterial phase acquisitions. Furthermore, this preference remained high at eighty-three percent during the portal venous phase. In contrast, the preference rate dropped to seventy-one percent in the delayed phase, which still represents a significant majority. Therefore, these results strongly support the routine use of GRASP-VIBE for young pediatric patients.

Clinical Implications for Pediatric Practice

These findings carry vital clinical implications, especially for clinical practices in developing healthcare markets like India. Pediatric imaging often requires general anesthesia to prevent motion blur from restless children. However, the free-breathing nature of GRASP-VIBE minimizes the need for heavy sedation. Consequently, this technique significantly reduces patient risk and operational costs. Moreover, the superior quality of the arterial phase images helps clinicians detect focal liver lesions with greater confidence. Thus, Indian diagnostic centers should consider integrating this sequence into their pediatric abdominal protocols.

Frequently Asked Questions

Q1: Why do radiologists prefer GRASP-VIBE over CAIPIRINHA-VIBE for pediatric scans?

Mainly, GRASP-VIBE allows pediatric patients to breathe normally during image acquisition. Consequently, this eliminates respiratory motion artifacts. In contrast, CAIPIRINHA-VIBE requires strict breath-holding, which young children frequently cannot maintain.

Q2: Does GRASP-VIBE require the child to undergo general anesthesia?

No, because GRASP-VIBE accommodates free breathing, it often eliminates the need for general anesthesia. Therefore, clinicians can perform dynamic scans on awake or lightly sedated children safely.

Q3: In which contrast phase does GRASP-VIBE show the highest preference rate?

Specifically, readers showed the highest preference during the portal venous and arterial phases. Furthermore, this technique outperformed the breath-hold sequence in every evaluated contrast phase.

References

1. Veldhoen S et al. Dynamic contrast-enhanced liver MRI in children: image quality comparison between GRASP-VIBE and CAIPIRINHA-VIBE. Eur Radiol. 2026 May 21. doi: 10.1007/s00330-026-12635-z. PMID: 42166014.
2. Morin CE et al. Best practices for pediatric liver MRI: guidelines from members of the Society for Pediatric Radiology Magnetic Resonance and Abdominal Imaging Committees. Pediatr Radiol. 2025;55(10):1638-1652.
3. Chandarana H et al. Free-breathing contrast-enhanced multiphase MRI of the liver using a combination of compressed sensing, parallel imaging, and golden-angle radial sampling. Invest Radiol. 2013;48(1):10-16.