title: Transmastoid reshaping of the sigmoid sinus: preliminary study of a novel surgical method to quiet pulsatile tinnitus of an unrecognized vascular origin.
abstract: OBJECTIVE A dominant sigmoid sinus with focal dehiscence or thinning (DSSD/T) of the overlying bony wall is a commonly encountered, but frequently overlooked, cause of vascular pulsatile tinnitus (VPT). Also, the pathophysiological mechanism of sound perception in patients with VPT remains poorly understood. In the present study, a novel surgical method, termed transmastoid SS-reshaping surgery, was introduced to ameliorate VPT in patients with DSSD/T. The authors reviewed a case series, analyzed the surgical outcomes, and suggested the pathophysiological mechanism of sound perception. The theoretical background underlying VPT improvement after transmastoid SS-reshaping surgery was also explored. METHODS Eight patients with VPT that was considered attributable to DSSD/T underwent transmastoid SS-reshaping surgery between February 2010 and February 2015. The mean postoperative follow-up period was 9.5 months (range 4-13 months). Transmastoid SS-reshaping surgery featured simple mastoidectomy, partial compression of the SS using harvested cortical bone chips, and reinforcement of the bony SS wall with bone cement. Perioperative medical records, imaging results, and audiological findings were comprehensively reviewed. RESULTS In 7 of the 8 patients (87.5%), the VPT abated immediately after surgery. Statistically significant improvements in tinnitus loudness and distress were evident on numeric rating scales. Three patients with preoperative ipsilesional low-frequency hearing loss exhibited postoperative improvements in their low-frequency hearing thresholds. No major postoperative complications were encountered except in the first subject, who experienced increased intracranial pressure postoperatively. This subsided after a revision operation for partial decompression of the SS. CONCLUSIONS Transmastoid SS-reshaping surgery may be a good surgical option in patients with DSSD/T, a previously unrecognized cause of VPT. Redistribution of severely asymmetrical blood flow, reinforcement of the bony SS wall with bone cement to reconstruct a soundproof barrier, and disconnection of a problematic sound conduction route via simple mastoidectomy silence VPT.
authors.affiliation: Seoul National University College of Medicine;|Soree Ear Clinic;
authors.forename: Chong Sun
authors.initials: CS
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea; and.
authors.forename: So Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea; and.
authors.forename: Hyunseok
authors.initials: H
authors.lastname: Choi
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea; and.
authors.forename: Ja-Won
authors.initials: JW
authors.lastname: Koo
authors.affiliation: Myungdong Yonsei ENT Clinic;
authors.forename: Shin-Young
authors.initials: SY
authors.lastname: Yoo
authors.affiliation: Graduate School of Convergence Science and Technology, Seoul National University, Seoul;
authors.forename: Gwang Seok
authors.initials: GS
authors.lastname: An
authors.affiliation: Graduate School of Convergence Science and Technology, Seoul National University, Seoul;
authors.forename: Kyogu
authors.initials: K
authors.lastname: Lee
authors.affiliation: Department of Communication Sciences and Disorders, The University of Iowa, Iowa City, Iowa.
authors.forename: Inyong
authors.initials: I
authors.lastname: Choi
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, Korea; and.
authors.forename: Jae-Jin
authors.initials: JJ
authors.lastname: Song
mesh_terms: D000328:Adult; D000368:Aged; D003392:Cranial Sinuses / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008416:Mastoid; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods; D014012:Tinnitus / Q000209:etiology / Q000601:surgery*; D014652:Vascular Diseases / Q000150:complications
keywords: CTA = CT angiography; DSSD/T = dominant sigmoid sinus with dehiscence or thinning; IICP = increased intracranial pressure; IJV = internal jugular vein; MRI/A = MRI with angiography; NRS = numeric rating scale; PT = pulsatile tinnitus; PTA = pure-tone audiometry; SS = sigmoid sinus; SSD = SS dehiscence; TB = temporal bone; VPT = vascular PT; cranial sinuses; mastoid; pulsatile tinnitus; surgical procedures, skull base