Table 3

Braid deformation patterns (F2B2): foreshortening, fish-mouthing, braid bump deformation, and braid collapse

TypeDefinitionLocationGradingComments
1Foreshortening*Movement on either or both ends of the FD towards the aneurysm neck of at least 5%ProximalYes, no, cannot determineClearly visible compared with specific previous image, no semiquantitative estimate
Distal
2Fish-mouthingConverging of focal FD end (cone shape) with more than 25% decrease of the outer FD diameter compared with expected continuation of FD shapeProximalNone (<25%)†, 25%–50%, >50% of braid diameter, cannot determineInvolves just the proximal and/or distal tip
Distal
3Braid bump deformationBraid bump or localized outward bulging of the FD mid-segmentMid-segment (mid 50%)Yes, no, cannot determineDeformation exceeds proximal and/or distal braid diameter; should have dense rim
4Braid collapseBottle-necked or cigar-shaped deformation diameter, decrease of >1/3 involving >1/3 of FD lengthEither proximal or distalYes, no, cannot determineCommonly noted, acutely requiring angioplasty or device removal; as opposed to fish-mouthing, involves a larger FD segment
  • *Foreshortening is reported by comparing any follow up-image compared with the final image of the index procedure. Elongation (which accompanies negative remodeling) or foreshortening ±5% of total length.

  • †Fish-mouthing of <25% cannot be reliably detected in typical standard of practice images with their different angulations of digital subtraction angiography (DSA) acquisitions and vessel anatomies.

  • FD, flow diverter.