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Comparative Study
. 2024 May 27;28(1):59.
doi: 10.1007/s10151-024-02925-3.

Validation of a 3D-printed model of cryptoglandular perianal fistulas

Affiliations
Comparative Study

Validation of a 3D-printed model of cryptoglandular perianal fistulas

C Verkade et al. Tech Coloproctol. .

Abstract

Introduction: Visualising the course of a complex perianal fistula on imaging can be difficult. It has been postulated that three-dimensional (3D) models of perianal fistulas improve understanding of the perianal pathology, contribute to surgical decision-making and might even improve future outcomes of surgical treatment. The aim of the current study is to investigate the accuracy of 3D-printed models of perianal fistulas compared with magnetic resonance imaging (MRI).

Methods: MRI scans of 15 patients with transsphincteric and intersphincteric fistulas were selected and then assessed by an experienced abdominal and colorectal radiologist. A standardised method of creating a 3D-printed anatomical model of cryptoglandular perianal fistula was developed by a technical medical physicist and a surgeon in training with special interest in 3D printing. Manual segmentation of the fistula and external sphincter was performed by a trained technical medical physicist. The anatomical models were 3D printed in a 1:1 ratio and assessed by two colorectal surgeons. The 3D-printed models were then scanned with a 3D scanner. Volume of the 3D-printed model was compared with manual segmentation. Inter-rater reliability statistics were calculated for consistency between the radiologist who assessed the MRI scans and the surgeons who assessed the 3D-printed models. The assessment of the MRI was considered the 'gold standard'. Agreement between the two surgeons who assessed the 3D printed models was also determined.

Results: Consistency between the radiologist and the surgeons was almost perfect for classification (κ = 0.87, κ = 0.87), substantial for complexity (κ = 0.73, κ = 0.74) and location of the internal orifice (κ = 0.73, κ = 0.73) and moderate for the percentage of involved external anal sphincter in transsphincteric fistulas (ICC 0.63, ICC 0.52). Agreement between the two surgeons was substantial for classification (κ = 0.73), complexity (κ = 0.74), location of the internal orifice (κ = 0.75) and percentage of involved external anal sphincter in transsphincteric fistulas (ICC 0.77).

Conclusions: Our 3D-printed anatomical models of perianal fistulas are an accurate reflection of the MRI. Further research is needed to determine the added value of 3D-printed anatomical models in preoperative planning and education.

Keywords: 3D printing; Fistula-in-ano; Perianal fistula.

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References

    1. Gaertner W, Burgess P, Davids J, Lightner A, Shogan B, Sun M, Steele SR, Paquette IM, Feingold DL (2022) The American society of colon and rectal surgeons clinical practice guidelines for the management of anorectal abscess, fistula-in-ano, and rectovaginal fistula. Dis Colon Rectum 65(8):964–985. https://doi.org/10.1097/DCR.0000000000002473 - DOI - PubMed
    1. Dekker L, Zimmerman DDE, Smeenk RM, Schouten R, Han-Geurts IJM (2021) Management of cryptoglandular fistula-in-ano among gastrointestinal surgeons in the Netherlands. Tech Coloproctol 25(6):707–719. https://doi.org/10.1007/s10151-021-02446-3 - DOI
    1. West RL, Zimmerman DD, Dwarkasing S, Hussain SM, Hop WC, Schouten WR, Kuipers EJ, Felt-Bersma RJ (2003) Prospective comparison of hydrogen peroxide-enhanced three-dimensional endoanal ultrasonography and endoanal magnetic resonance imaging of perianal fistulas. Dis Colon Rectum 46(10):1407–1415. https://doi.org/10.1007/s10350-004-6758-z - DOI - PubMed
    1. Buchanan GN, Halligan S, Bartram CI, Williams AB, Tarroni D, Cohen CR (2004) Clinical examination, endosonography, and MR imaging in preoperative assessment of fistula in ano: comparison with outcome-based reference standard. Radiology 233(3):674–681. https://doi.org/10.1148/radiol.2333031724 - DOI - PubMed
    1. Sahnan K, Adegbola SO, Tozer PJ, Gupta A, Baldwin-Cleland R, Yassin N, Warusavitarne J, Faiz OD, Hart AL, Phillips RKS, Lung PFC (2018) Improving the understanding of perianal crohn fistula through 3D modeling. Ann Surg 267(6):e105–e107. https://doi.org/10.1097/SLA.0000000000002629 - DOI - PubMed

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