Stent-in-stent Side-by-side Technical success + + + + + + Clinical success + + + + + + Ease of stent revision + + + + + Technical tips - Need dilation of the first stent’s mesh  using balloon or dilators - First stent insertion into more difficult side - Using large-open cell type stent will be easier for second stent insertion and stent revision in case of first stent occlusion - Distal ends of both stents should be in the same level and outside the ampulla - First stent insertion into more difficult side Preferable stent types - First stent should be large-open cell type mesh or special designed stent for Y- configuration - Second stent should be large-open cell type mesh - Second stent should be small introducer - Both stents should be small introducer( ≤ 7Fr.) and small diameter

Table 1: Technical tips and preferable stent types to be considered for stent-in-stent and side-by-side technique.