Surgery for Cochlear and Other Auditory Implants

Cases
Videos
Preface
Contributors
About the Authors
1 History of Auditory Implantation
1.1 Forerunners
1.1.1 Alessandro Volta (1745–1827)
1.1.2 Homer Dudley: the Vocoder
1.1.3 Wever and Bray: the Cochlear Microphonic
1.1.4 S.S. Stevens: Electrophonic Hearing
1.2 Pioneers and Experimentation
1.2.1 In France
1.2.2 Early American Years
1.2.3 Later American Years
1.3 Feasibility, Safety, and Evaluation Studies
1.3.1 The Bilger Report
1.4 Development of a Multichannel Device
1.4.1 United States, Australia, Austria, and France
1.4.2 Graeme Clark, Melbourne University Australia (1935)
1.4.3 Anxiety and Hostility in Deaf Communities
1.5 Development of the Auditory Brainstem Implant
1.5.1 Auditory Brainstem Implant
1.5.2 Summary of Discoveries and Developments
1.5.3 New Developments and Future
2 Surgical Anatomy in Auditory Implantation
2.1 Anatomy of the Middle Ear and Mastoid
2.1.1 The Mastoid
2.1.2 The Antrum
2.1.3 The Tympanic Cavity
2.1.4 The Ossicles
2.1.5 The Oval Window
2.1.6 The Facial Nerve
2.1.7 The Chorda Tympani
2.1.8 The Cochleariform Process and Tensor Tympani Muscle
2.1.9 The Round Window
2.1.10 The Facial Recess and the Posterior Tympanotomy
2.1.11 The Labyrinth
2.1.12 The Sigmoid Sinus and Jugular Bulb
2.1.13 The Carotid Artery
2.1.14 Facial Recess versus Subtotal Petrosectomy
2.2 Anatomical Dissection of Left Temporal Bone for Cochlear Implantation
2.3 Anatomy of the Lateral Skull Base, Brainstem, and Cochlear Nucleus
2.3.1 Internal Auditory Canal
2.3.2 Anatomy of the Posterior Fossa Related to ABI Surgery
3 Radiology in Auditory Implantation
3.1 General Radiology of the Temporal Bone
3.1.1 Computed Tomography
3.1.2 Magnetic Resonance Imaging
3.2 Radiology in Cochlear Implantation
3.3 Radiology in Auditory Brainstem Implantation
3.4 Axial and Coronal CT Sections
3.4.1 CT Mastoid Axial Images
3.4.2 CT Mastoid Coronal Images
3.5 Magnetic Resonance Imaging
3.5.1 Artifact of Cochlear and Auditory Brainstem Implant on MRI
4 Instruments and Implants
4.1 Cochlear Implantation: Instruments, Monitoring, and Implants
4.1.1 Instruments for Cochlear Implant (CI) Surgery
4.1.2 Perioperative Medication in CI Surgery
4.1.3 Monitoring and Electrophysiologic Testing during CI Surgery
4.1.4 Cochlear Implants and Electrodes Currently Available
4.2 Auditory Brainstem Implantation: Instruments, Monitoring, and Implants
4.2.1 Surgical Instruments in ABI Surgery
4.2.2 Management of Bleeding in ABI Surgery
4.2.3 Monitoring of Facial and Cochlear Nerves in ABI (or CI) Surgery
4.2.4 Intraoperative Cochlear Nerve Monitoring (ABR and CNAP)
4.2.5 Perioperative Medication and Care in ABI Surgery
4.2.6 Implants for Brainstem Implantation
5 Cochlear Implantation
5.1 Cochlear Implant Candidates
5.2 Etiology of Hearing Loss
5.3 Current Indications for Cochlear Implantation
5.3.1 Contraindications for Cochlear Implantation
5.3.2 Special Indications, Differential Work-up, and Special Surgical Techniques
5.4 Surgical Steps
5.4.1 Skin Incision
5.4.2 Musculoperiosteal Layer
5.4.3 Mastoidectomy and Posterior Tympanotomy
5.4.4 Exposure of the Round Window
5.4.5 Drill-out of the Receiver Well
5.4.6 Fixation of the Implant
5.4.7 Cochleostomy
5.4.8 Insertion of the Cochlear Electrode
5.4.9 Electrophysiologic Testing
5.4.10 Fixation of the Implant
5.4.11 Closure
Cases 5.1–5.2
5.5 Risks and Complications of Cochlear Implantation
6 Special Considerations in Pediatric Cochlear Implantation
6.1 Position of the Facial Nerve
6.2 The Anatomical Relations between the Facial Recess, the Round Window, and the Basal Turn in Children
6.3 Growth of the Temporal Bone
6.4 Bone Marrow and Blood Loss
6.5 Fixation of the Receiver-Stimulator
6.6 Anesthesiologic Technique
6.7 Electrophysiologic Measurements
6.8 Bilateral Pediatric Cochlear Implantation
6.8.1 Surgical Considerations in Bilateral Implantation
6.8.2 Special Steps in Bilateral Implantation
7 Complications and Revision Surgery in Cochlear Implantation
7.1 Major Complications
7.2 Minor Complications
7.3 Device Failure Complications
7.3.1 Hard Device Failure
7.3.2 Soft Device Failure
7.4 Pediatric vs. Adult Complication Rate
7.5 Bilateral vs. Unilateral Implant Complication Rates
7.6 Therapeutic Options for Several Complications
7.6.1 Flap Infection/Subcutaneous Hematoma or Seroma
7.6.2 Receiver-Stimulator or Electrode Extrusion
7.6.3 Facial Nerve Stimulation
7.6.4 Facial Nerve Injury
7.6.5 Electrode Placement
7.6.6 CSF Gusher/CSF leakage
7.6.7 Revision Surgery/Re-implantation
Cases 7.1–7.10
8 Auditory Brainstem Implantation
8.1 Rationale
8.2 Indications
8.2.1 Neurofibromatosis Type 2
8.2.2 Postmeningitis Ossification
8.2.3 Inner Ear Malformation
8.2.4 Cochlear Nerve Aplasia/Cochlear Nerve Deficiency
8.3 Controversial Indications
8.3.1 Otic Capsule Fracture and Cochlear Nerve Avulsion
8.3.2 Bilateral or Unilateral Patent Cochlea
8.3.3 Vestibular Schwannoma in the Only Hearing Ear
8.3.4 Autoimmune Inner Ear Disease
8.3.5 Von Hippel–Lindau Disease
8.3.6 Auditory Neuropathy
8.3.7 Otosclerosis
8.4 Indications for ABI/CI: Summary
8.5 Surgical Steps of Auditory Brainstem Implantation
8.5.1 Surgical Anatomy
8.5.2 Surgical Approach
8.5.3 Intraoperative Monitoring
8.6 Surgical Anatomy in Auditory Brainstem Implantation
8.7 Surgical Steps in Auditory Brainstem Implantation
8.8 Surgical Steps According to the Indication
8.9 Summary of Auditory Brainstem Implants
9 Electroacoustic Stimulation
9.1 Hearing Preservation and Electroacoustic Stimulation
9.2 Indication for EAS
9.3 Influential Factors in Hearing Preservation
9.3.1 Atraumatic Surgical Technique
9.3.2 Atraumatic Electrode Design
9.3.3 Perioperative Use of Medication
Cases 9.1–9.2
10 Subtotal Petrosectomy in Cochlear Implantation
10.1 Indications
10.1.1 Chronic Otitis Media/Cholesteatoma/Osteoradionecrosis of the Temporal Bone
10.1.2 Presence of a Radical Cavity/Canal Wall Down Technique
10.1.3 Cochlear Ossification/Obliteration
10.1.4 Inner Ear Malformations
10.1.5 Fracture of the Temporal Bone with Otic Capsule Involvement
10.1.6 Revision Cases
10.1.7 Unfavorable Anatomical Conditions for Posterior Tympanotomy
10.2 Contraindications
10.3 Surgical Procedure
10.3.1 Skin Incision
10.3.2 Anterior Pedicled Flap
10.3.3 Blind-sac Closure of the External Meatus
10.3.4 Removal of the Skin of the Lateral Portion of the External Ear Canal
10.3.5 Canal Wall Down Mastoidectomy
10.3.6 Removal of the Skin of the Medial Portion of the External Ear Canal with Annulus, Malleus, and Incus
10.3.7 Exposure and Closure of Eustachian Tube
10.3.8 Drill-out of the Receiver Well
10.3.9 Harvesting of Abdominal Fat
10.3.10 Exposure of the Round Window
10.3.11 Insertion of the Cochlear Electrode
10.3.12 Electrophysiologic Testing
10.3.13 Fixation of the Implant
10.3.14 Obliteration of Cavity with Fat
10.3.15 Closure
Case 10.1
11 Cochlear Implantation in Cochlear Ossification
11.1 Fibrosis and Ossification Process
11.2 Management Work-up
11.2.1 Fast Diagnostic Work-up
11.2.2 Extended Diagnostic Work-up
11.3 Audiometric Evaluation
11.4 CT and MRI
11.4.1 Fibrosis and Ossification on Imaging
11.5 Surgical Planning
11.5.1 Classification of Ossification and Surgical Strategy
11.5.2 Autoimmune Inner Ear Disease
11.6 Indication for Bilateral Implantation
11.7 Creating Awareness
11.8 Surgical Steps in Ossification
11.8.1 Partial Drill-out of the Basal Turn
11.8.2 Scala Vestibuli Insertion
11.8.3 Complete Basal Turn Drill-out
11.8.4 Middle Turn Cochleostomy with Double Array Insertion
11.8.5 Middle Turn Drill-out with Double Array Insertion
11.8.6 No Lumen Found: Indication for ABI
11.9 Types of Electrodes
11.9.1 Dummy Electrode
Cases 11.1–11.3
11.10 Risks in Surgery for Ossified Cochlea
12 Meningitis and Implantation
12.1 Introduction
12.2 Hearing Loss after Bacterial Meningitis
12.3 Audiologic Follow-up after Meningitis
12.4 Postmeningitis Hearing Evaluation and Treatment Flowchart
12.4.1 First Hearing Evaluation
12.4.2 Dexamethasone
12.4.3 Obliteration
12.4.4 Hearing Loss of 30 dB or More
12.4.5 Radiologic Phases of Inflammation, Fibrosis, and Ossification14,23,24
12.5 Early Postmeningitis Radiology and Decision Making
12.5.1 Unilateral Hearing Loss and Radiology
12.5.2 Bilateral 0–30 dB Loss and Radiology
12.5.3 Bilateral 30–70 dB Loss and Radiology
12.5.4 Bilateral > 70 dB Loss and Radiology
12.6 Difficulties in the Assessment Phase
12.6.1 Audiologic Assessment in Infants
12.6.2 Imaging in Infants
12.6.3 Other Sequelae of Meningitis
12.6.4 Counseling Parents
12.7 Decision Making
12.7.1 Hearing and MRI Assessment
12.7.2 Ossification
12.7.3 ABI in Postmeningitis Cases
Cases 12.1–12.6
13 Auditory Implantation in Otosclerosis Patients
13.1 Otosclerosis
13.2 CT Classification in Otosclerosis
13.3 Decision Making in Otosclerosis
13.4 Treatment Algorithm
13.5 Surgical Difficulties and Management in Cochlear Implantation in Advanced Otosclerosis
Cases 13.1–13.8
14 Otomastoiditis and Cochlear Implantation
14.1 Chronic Suppurative Otitis Media
14.1.1 Preoperative Evaluation
14.1.2 Surgical Treatment
14.1.3 Postoperative Imaging
14.1.4 Special Populations
14.2 Otitis Media with Effusion
14.3 Postoperative Chronic Middle Ear and Mastoid Disease
14.4 Acute Postoperative Middle Ear and Mastoid Infection
14.5 Removal of Cochlear Electrode and Use of Dummy Electrode
14.5.1 Dummy Electrode
Cases 14.1–14.3
15 Inner Ear Malformations and Implantation
15.1 Introduction
15.2 Embryology
15.3 Classification of Malformations
15.3.1 Malformation of the Membranous Labyrinth
15.3.2 Malformations of the Membranous and Osseous Labyrinth
15.3.3 Malformation of the Cochlear Nerve and Inner Ear Canal
15.4 Cochlear and Auditory Brainstem Implantation in Malformations
15.4.1 Cochlear Implantation in IP-2
15.4.2 Cochlear Implantation in IP-3
15.4.3 Cochlear Implantation in Cochlear Hypoplasia
15.4.4 Cochlear Implantation in IP-1
15.4.5 Cochlear Implantation in Common Cavity
15.4.6 Cochlear Implantation or ABI in CHARGE
15.4.7 ABI or CI in Common Cavity or Aplasia of the Cochlea?
15.4.8 ABI or CI in Cochlear Nerve Aplasia or a Small IAC?
15.4.9 Auditory Brainstem Implantation in Labyrinthine Aplasia (Michel Deformity)
15.5 Risks in Malformation CI Surgery
15.5.1 Facial Nerve Injury
15.5.2 Facial Nerve Stimulation
15.5.3 CSF Gusher
15.5.4 Meningitis
15.5.5 Complications
15.5.6 No Auditory Effect/Nonuse
15.6 Summary
15.6.1 Inner Ear Malformations
15.6.2 Internal Auditory Canal and Vestibulocochlear Nerve Malformations
15.6.3 CI or ABI
15.6.4 Results of Implantation
Cases 15.1–15.7
16 Neurofibromatosis Type 2 and Auditory Implantation
16.1 Difference in Comparison with Sporadic Vestibular Schwannoma
16.2 Clinical Diagnosis
16.3 Clinical Manifestations of Disease
16.4 Management
16.5 Vestibular Schwannoma
16.6 Other Tumors
16.7 Surveillance
16.8 Decision Making
16.8.1 Tumor Size
16.8.2 Preoperative Hearing
16.8.3 Complications of the Tumor
16.9 Type of Operation
16.10 Operation Side
16.11 ABI in Neurofibromatosis Type 2
16.12 Indications and Contraindications for Auditory Brainstem Implants
16.13 Removable Magnet in ABI Implants
16.14 First-side Versus Second-side Surgery
16.15 Promontory Testing
16.16 Surgical Considerations
16.16.1 Intraoperative Monitoring
Cases 16.1–16.5
16.17 Summary of NF2 and Implantation
17 Implantation in Skull Base and Temporal Bone Lesions
17.1 CI versus ABI
17.2 Preoperative Conditions
17.3 Intraoperative Audiometric Testing
17.4 Indications
17.4.1 Skull Base Lesions
17.4.2 Previous Radiotherapy
17.4.3 Non–Skull Base Lesions
17.5 Contraindications and Risks of Implantation in Skull Base Surgery/Neurotology
Cases 17.1–17.4
18 Bone Conduction Implants
18.1 Indications
18.1.1 Audiologic Indications
18.1.2 Otologic Indications
18.2 Contraindications
18.3 Implantable Devices with Transcutaneous Abutment
18.3.1 Preoperative Evaluation
18.3.2 Key Features of the Devices
18.3.3 Specific Indications
18.3.4 Contraindications
18.3.5 Surgical Technique
18.3.6 Postoperative Management and Follow-up
18.3.7 Placement of an Implantable Device with Transcutaneous Abutment Using the Skin Thinning Technique: Surgical Steps
Cases 18.1–18.2
18.4 Complications
18.4.1 Intraoperative Complications
18.4.2 Postoperative Complications
18.5 Implantable Devices without Transcutaneous Abutment
18.5.1 Preoperative Evaluation
18.5.2 Key Features of the Devices
18.5.3 Specific Indications
18.5.4 Contraindications
18.5.5 Postoperative Management and Follow-up
18.5.6 Placement of the Bonebridge System: Surgical Steps
Case 18.3
18.5.7 Placement of the Alpha System: Surgical Steps
Case 18.4
19 Active Middle Ear Implants: Vibrant Soundbridge
19.1 Indications
19.2 Contraindications
19.3 Preoperative Evaluation
19.4 Postoperative Management and Follow Up
19.5 Surgical Steps: Incus Vibroplasty
19.5.1 Incision of Skin and Soft Tissues
19.5.2 Mastoidectomy and Posterior Tympanotomy
19.5.3 Implant Positioning
19.5.4 Audiometric Testing
19.5.5 Closure
Case 19.1
19.6 Surgical Steps: Round Window Vibroplasty
19.6.1 Incision of Skin and Soft Tissues
19.6.2 Subtotal Petrosectomy
19.6.3 Implant Positioning
19.6.4 Audiometric Testing
19.6.5 Closure
Case 19.2
19.7 Results and Complications of VSB placement
Index

This comprehensive, high-level surgical reference and atlas is tailored for surgeons who are undertaking training for cochlear implant procedures and implantable auditory devices and for experienced surgeons who would like to expand their knowledge, improve their skills and outcomes, and learn advanced surgical techniques. Following the principle underlying Professor Sanna’s other successful publications, Surgery for Cochlear and Other Auditory Implants takes an integrated approach to anatomy, imaging, technology, decision making, surgical procedures described step by step, and clinical cases. This book allows readers to: Improve the efficiency and outcomes of cochlear implantation and other auditory implant surgeries Learn the required basic and advanced surgical techniques Evaluate different surgical options and types of implants Review common and uncommon variations of anatomy and malformations Understand issues and surgical modifications unique to pediatric cochlear implantation, to revision surgery, and in postmeningitis, otosclerosis, and NF2 cases Find decision-making algorithms for difficult pathologies Examine common and not so common intraoperative dilemmas and identify strategies to resolve them Review preoperative assessment and set up and outcomes Find out about classification systems in cochlear implant failure, malformations, otosclerosis, and post meningitis Supplementing the 1200 images within the book are 15 outstanding videos available on Thieme’s MediaCenter demonstrating the implantation of the different cochlear implantation devices that are currently available and the application of brainstem implants in these situations: tumor removal, malformation (missing auditory nerve in children), and cochlear ossification.