The Van Assche score on pelvic MRI

What is known

• Introduced by van Assche in 2003 for CD-related fistula, scoring tract location, abscesses, proctitis, and T2 signal intensity (original range 0–22). ^1–3
• The 2011/2017 modified version added T1 hyperintensity and infiltrate for more detailed classification (range 0–19.5). ^1–3
• Widely adopted in clinical trials and longitudinal studies to monitor response to anti-TNF therapy, with a lower score indicating positive response. ^2,4
• MRI score may uncover clinically relevant severity overlooked by clinical evaluation alone, potentially informing prognosis of durable response. ³

What is unknown / caveats

• Score change can be discordant with clinical response. In one cohort it did not drop in ~1/3 of responders and did drop in 43% of non-responders
• Insensitive to specific changes such as extent of inflammatory tissue within tracts; may lag internal healing
• Routine everyday use is variable; validated cut-offs for clinically relevant change are not established
• Newer indices (modified van Assche, MAGNIFI-CD) aim to improve sensitivity to change, and the added value over cheaper clinical assessment remains debated.

References

1. Wang WG, Lu WZ, Yang CM, Yu KQ, He HB. Modified Van Assche magnetic resonance imaging-based score for assessing the clinical status of anal fistulas. Medicine (Baltimore). 2020;99(19):e20075. PMID: 32384475.

2. Arkenbosch JHC, van Ruler O, de Vries AC, van der Woude CJ, Dwarkasing RS. The role of MRI in perianal fistulizing disease: diagnostic imaging and classification systems to monitor disease activity. Abdom Radiol (NY). 2025;50(2):589-597. PMID: 39180667.

3. van Rijn KL, Lansdorp CA, Tielbeek JAW, Nio CY, Buskens CJ, D'Haens GRAM, Löwenberg M, Stoker J. Evaluation of the modified Van Assche index for assessing response to anti-TNF therapy with MRI in perianal fistulizing Crohn's disease. Clin Imaging. 2020;59(2):179-187. PMID: 31821976.

4. Maccioni F, Busato L, Bottino L, Longhi A, Valenti A, Zippi M, Catalano C. Comprehensive Imaging Evaluation and Staging of Crohn's Disease: When and Why to Use Intestinal Ultrasound, MRE, or CTE: Current Guidelines and Future Directions. Diagnostics (Basel). 2026;16(6). PMID: 41897617.

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Draft, generated by the IBDology RAG and not yet clinician-reviewed. Answers are grounded in the retrieved literature listed above; a high faithfulness score means the answer matches its sources, not that the sources are correct.