Clinical assessment and imaging are key in determining the severity of Hidradenitis Suppurativa (HS). MRI has been shown to have utility in evaluating severity in complex cases of HS. [1] Accurate imaging assessment relies on high resolution imaging protocols, multiplanar reconstructions and increasingly advanced modelling techniques such as segmentation and 3D rendering. This pictorial essay will illustrate the utility of dedicated pelvic MRI for the delineation of disease extent. Additionally, it will touch on the use of 3D modelling and visualisation for simplification of this...

HS it is a chronic autoinflammatory disease centered on the hair follicle, characterised by recurrent abscesses and sinus tracts. The causative pathways are complex, but have been found to involve cytokines TNFa, IL17 and Il1 among others. [2] HS generally develops after puberty and has varying degrees of severity described in the Hurley Classification stages 1-3. The prevalence in persons >15 years of age is ~1% in the European population. The distribution within sex is uneven, with the female to male ratio being 3:1. Approximately...

Three complex HS cases demonstrating extent of the disease, associated complications, and manifestations of HS on MRI, have been selected by a musculoskeletal radiologist, dermatologist, and plastic surgeon at a large tertiary hospital in Australia. The extent of disease can often be underestimated both clinically and radiologically and these annotated cases will demonstrate the complex and interconnected nature of the subcutaneous fistulas that characterise the severe end of the disease spectrum. Imaging findings will be displayed with reference to the clinical Hurley staging system. [4]...

This educational piece describes the MRI findings in complex cases of HS to improve teaching and training among radiologists, and surgeons while also demonstrating potential exciting future developments in clinical application of 3D segmentation and modelling of this complex disease.

References Lam D, Yong E, D'Souza B, Woods R. Three-Dimensional Modeling for Crohn's Fistula-in-Ano: A Novel, Interactive Approach. Dis Colon Rectum. 2018;61(5):567-72. Zouboulis CC, Desai N, Emtestam L, Hunger RE, Ioannides D, Juhasz I, et al. European S1 guideline for the treatment of hidradenitis suppurativa/acne inversa. J Eur Acad Dermatol Venereol. 2015;29(4):619-44. Jemec GBE. Hidradenitis Suppurativa. New England Journal of Medicine. 2012;366(2):158-64. Ovadja ZN, Schuit MM, van der Horst C, Lapid O. Inter- and intrarater reliability of Hurley staging for hidradenitis suppurativa. Br J Dermatol....