Luis Loureiro, Paulo Almeida, Samuel Cardoso, Romaric Loffroy, Rui Machado
Onyx-only haemorrhoidal artery embolisation was technically feasible with encouraging updated bleeding control. The observed association between bilateral treatment and fewer staged procedures is hypothesis-generating and may partly reflect an operator learning curve.
PURPOSE: To report an initial single-centre experience with Onyx-18-only superior rectal artery embolisation for bleeding internal haemorrhoids, focusing on technical feasibility, treatment laterality, and updated clinical outcomes.
MATERIALS AND METHODS: Consecutive Onyx-only procedures performed between October 2023 and April 2026 in patients with bleeding-predominant internal haemorrhoids were retrospectively reviewed. Patients with portal hypertension/cirrhosis were excluded because of the distinct pathophysiology of anorectal bleeding. Patient-level clinical outcomes and procedure-level technical variables were analysed separately. Updated telephone follow-up was obtained on 12 August 2026.
RESULTS: Six patients underwent 9 procedures. Technical success was achieved in all procedures. Three patients were treated bilaterally at the initial session and 3 initially unilaterally; 2 of the latter required staged contralateral embolisation. At updated follow-up, all 6 patients reported absence of rectal bleeding after completion of treatment. Median follow-up was 19.5 months (range, 4-34), and 5 of 6 patients had at least 12 months of follow-up. One transient episode of rectal pain occurred; no major or clinically evident ischaemic complication was observed.
CONCLUSION: Onyx-only haemorrhoidal artery embolisation was technically feasible with encouraging updated bleeding control. The observed association between bilateral treatment and fewer staged procedures is hypothesis-generating and may partly reflect an operator learning curve.