title: Topographic bone thickness maps for Bonebridge implantations.
abstract: Bonebridge™ (BB) implantation relies on optimal anchoring of the bone-conduction implant in the temporal bone. Preoperative position planning has to account for the available bone thickness minimizing unwanted interference with underlying anatomical structures. This study describes the first clinical experience with a planning method based on topographic bone thickness maps (TBTM) for presigmoid BB implantations. The temporal bone was segmented enabling three-dimensional surface generation. Distances between the external and internal surface were color encoded and mapped to a TBTM. Suitable implant positions were planned with reference to the TBTM. Surgery was performed according to the standard procedure (n = 7). Computation of the TBTM and consecutive implant position planning took 70 min on average for a trained technician. Surgical time for implantations under passive TBTM image guidance was 60 min, on average. The sigmoid sinus (n = 5) and dura mater (n = 1) were exposed, as predicted with the TBTM. Feasibility of the TBTM method was shown for standard presigmoid BB implantations. The projection of three-dimensional bone thickness information into a single topographic map provides the surgeon with an intuitive display of the anatomical situation prior to implantation. Nevertheless, TBTM generation time has to be significantly reduced to simplify integration in clinical routine.
authors.affiliation: ARTORG Center for Biomedical Engineering Research, University of Bern, Murtenstrasse 50, 3010, Bern, Switzerland.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Wimmer
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gerber
authors.forename: Jérémie
authors.initials: J
authors.lastname: Guignard
authors.forename: Patrick
authors.initials: P
authors.lastname: Dubach
authors.forename: Martin
authors.initials: M
authors.lastname: Kompis
authors.forename: Stefan
authors.initials: S
authors.lastname: Weber
authors.forename: Marco
authors.initials: M
authors.lastname: Caversaccio
mesh_terms: D000328:Adult; D000368:Aged; D001844:Bone Conduction / Q000502:physiology*; D005240:Feasibility Studies; D034381:Hearing Loss / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods; D017755:Prosthesis Fitting / Q000379:methods*; D019919:Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D015203:Reproducibility of Results; D025321:Surgery, Computer-Assisted; D013701:Temporal Bone / Q000033:anatomy & histology / Q000601:surgery