MedPath

Maintaining Cochlear Patency After VIIIth Nerve Surgery

Not Applicable
Withdrawn
Conditions
Profound Hearing Impairment
Labyrinthitis Ossificans
Acoustic Neuroma
Interventions
Device: MedEl Test Electrode Placer
Registration Number
NCT03261726
Lead Sponsor
Eric W. Sargent, MD
Brief Summary

Tumors arising from the VIIIth Nerve (vestibulo-cochlear nerve) typically present with progressive unilateral hearing loss and tinnitus. VIIIth Nerve tumors with documented growth on serial MRI scans typically lead to deafness in the affected ear over time. Radiation (Gamma Knife® or stereotactic radiosurgery) may preserve hearing in \~80% while surgery (middle cranial fossa or retrosigmoid approach) may preserve hearing in 16 - 40% of small tumors, although initial hearing preservation by both modalities may fail over time. Surgical resection via the translabyrinthine approach is the safest way to remove many of these tumors, but involves loss of all hearing. In all treatment modalities, the vascular supply (the labyrinthine artery, a terminal branch of AICA with no collaterals) to the cochlea is at risk. After devascularization, the cochlea frequently fills with fibrous tissue or ossifies (labyrinthitis ossificans), making it impossible to place a cochlear implant should it be required later. The incidence of this is 46% in our patients. This study seeks to determine the feasibility of preserving the cochlear duct with an obdurator so that patients undergoing translabyrinthine removal of VIIIth nerve tumors may retain the option of a cochlear implant at a later time.

Detailed Description

Not available

Recruitment & Eligibility

Status
WITHDRAWN
Sex
All
Target Recruitment
Not specified
Inclusion Criteria
  • patients of all ages with unilateral or bilateral acoustic neuromas who face loss of hearing in 1 ear from surgical removal via a translabyrinthine approach.
  • patients do not meet criteria for conventional cochlear implantation or auditory brainstem implantation.
  • tumor removal must allow preservation of the auditory division of the VIIIth cranial nerve.
  • the patient must be willing to undergo preoperative S pneumococcus immunization protocol recommended by the US CDC immunization recommendations for cochlear implant patients.
Exclusion Criteria
  • inability to preserve the auditory division of the VIIIth cranial nerve during tumor removal ossification or fibrosis of the cochlea found on preoperative imaging (CT or MRI) that precludes cochlear implantation.
  • active middle ear disease.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
MedEl Test Electrode PlacerMedEl Test Electrode PlacerMedEl Test Electrode Placed at VIIIth nerve tumor resection
Primary Outcome Measures
NameTimeMethod
Incidence of Treatment-Emergent Adverse Events related to implanted insertion electrodeOne year postoperatively

Office visits and MRI monitoring:

1. 2 - 3 weeks after surgery: Routine post-operative visit for wound care. I. Document integrity and appearance of the eardrum. II. Document wound integrity and appearance.

2. 3 - 4 months after surgery: Monitoring MRI with and without contrast of the inner ear/internal auditory canals with routine post-operative visit. I. Document integrity and appearance of the eardrum. II. Document wound integrity and appearance. III. Document appearance of the cochlea on heavily T2-weighted images.

3. Study Endpoint: 1 year after surgery. Repeat MRI with and without contrast of the inner ear/internal auditory canals. I. Document integrity and appearance of the eardrum. II. Document wound integrity and appearance. III. Document appearance of the cochlea on heavily T2-weighted images.

Secondary Outcome Measures
NameTimeMethod
Presence or absence of fluid in the cochlea3- 4 months and 1 year after tumor removal and implantation of the insertion electrode

Appearance of the implanted cochlea on heavily T2-weighted monitoring MRI 3-4 months after surgery and 1 year after surgery.

Trial Locations

Locations (1)

The Michigan Ear Institute

🇺🇸

Farmington Hills, Michigan, United States

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