10Atraumatic Surgery: Preserving Hearing and Balance Together
Because both residual hearing and vestibular function fall to the same hydraulic and fibrotic insults, the same soft-surgery lever protects both. Round-window entry, slow insertion, stable slim arrays and peri-operative steroids each lower the pressure transient and the foreign-body reaction. Structure preservation reframes balance protection as a surgical-technique decision.
TOne lever, two senses
Hearing and vestibular preservation are closely associated in implanted individuals and are addressed by the same structure-preservation strategies Minimizing intracochlear pressure variation — slow insertion, round window over cochleostomy, avoiding CSF-gusher pressurization — protects both residual hearing and vestibular function The term 'soft surgery' for preserving inner-ear structures was first used in 1993.[2022]
TApproach and array choices
The round-window approach reduces subjective dizziness compared with antero-inferior cochleostomy Stiff electrode arrays produce greater caloric reduction and more dizziness, while a slim flexible lateral-wall array via the round window is the practical default for whole-inner-ear preservation Insertion speed, CSF gusher and electrode stabilization each show significant effects on hearing preservation.[2008][2016]
CPharmacologic and emerging adjuncts
Methylprednisolone applied directly to the round window reduced post-operative dizziness in a randomized clinical trial Robotic insertion can be less traumatic than manual, with fewer translocated electrodes in reported series Even with major soft-surgery advances, 100% hearing preservation remains elusive, and children show superior sustained hearing preservation than adults.[2011][2022]
CWhere preservation surgery is heading
The hearing-preservation ethos (perilymphatic, atraumatic, narrow electrode) is the shared bridge between modern soft-surgery CI and emerging vestibular implants Vestibular-implant work uses electrodes only ~150 µm wide, narrower than a hybrid CI electrode, designed not to compress the membranous labyrinth In rhesus monkeys implanted with such narrow electrodes, hearing was completely preserved in 5 of 8 animals, demonstrating combined function preservation is feasible.[2012][2022]
Which combination of choices best serves both goals?
Compared with antero-inferior cochleostomy, the round-window approach is associated with:
In a randomized trial, what intervention reduced post-CI dizziness?