Table 2.

Summary of studies comparing transperineal ultrasound with magnetic resonance imaging or surgical findings in perianal Crohn’s disease and inflammatory bowel disease

Ref.	No. of patients	Patient characteristics	Concordance rate (TPUS vs MRI or surgery)	Main findings
Maconi et al[2], 2013	59	Adults with CD, prospective	κ = 0.78 (fistulae classification)	TPUS sensitivity 94%, PPV 93%; less accurate for extrasphincteric/suprasphincteric tracts and deep abscesses
Bor et al[16], 2016	23	Adults with complicated CD	Not specified	TPUS 100% sensitivity for fistulae and abscesses; outperformed MRI and TRUS
Jung et al[13], 2022	29	Pediatric CD on biologics	κ = 0.49	TPUS had high specificity (93%) and PPV (95%) for assessing treatment response vs MRI
Lee et al[12], 2018	38	Pediatric CD with PACD	κ = 0.30-0.62	TPUS better concordance with MRI than colonoscopy; sensitivity 76% for fistulae, 56% for abscesses
Wedemeyer et al[18], 2004	25	Adults with active PACD	κ > 0.83	TPUS detected 90% of fistulas and 86% of abscesses; comparable to MRI; especially useful in anal stenosis
Terracciano et al[17], 2016	28	IBD patients	Sensitivity 100% for RVF and superficial abscess; κ = 0.34 for deep abscess	TPUS highly concordant with MRI for Parks (κ = 0.67) and AGA (κ = 0.83) classifications; superior for RVF and superficial abscesses

TPUS: Transperineal ultrasound; MRI: Magnetic resonance imaging; CD: Crohn’s disease; PACD: Perianal Crohn’s disease; TRUS: Transrectal ultrasound; RVF: Rectovaginal fistula; AGA: American Gastroenterological Association, κ: Cohen’s kappa statistic; PPV: Positive predictive value.