Otosclerosis

Diagnosis, Evaluation, Pathology,

Surgical Techniques, and Outcomes

Chris de Souza, MS, DORL, DNB, FACS

Marcos V. Goycoolea, MD, MS, PhD

Neil M. Sperling, MD, FACS

Contents

List of Videos vii

Introduction ix

Contributors xi

Part I. Basic Science 1

Chapter 1. Pathology of Otosclerosis 3

Chapter 2. Genetics of Otosclerosis 9

Chapter 3. Measles and Otosclerosis 11

Chapter 4. Molecular Biology 13

Part II. Investigations 15

Chapter 5. Audiological Evaluation of the Patient with Otosclerosis 17

Chapter 6. Radiological Imaging of Otosclerosis 25

Part III. Cochlear Otosclerosis and Conservative Management of Otosclerosis 29

Chapter 7. Cochlear Otosclerosis 31

Chapter 8. Medical Treatment of Otosclerosis 37

Chapter 9. Hearing Aids and Otosclerosis 43

Part IV. Surgical Management of Otosclerosis 47

Chapter 10. Stapedectomy 49

Chapter 11. Stapedectomy Versus Stapedotomy 53

Chapter 12. Lasers in Otosclerosis 57

Chapter 13. The Stapedectomy Prosthesis 61

Chapter 14. Bilateral Otosclerosis 63

Chapter 15. Revision Stapedectomy 65

Part V. Complications of Stapedectomy 69

Chapter 16. Post-Stapedectomy Perilymph Fistula 71

Part VI. Miscellaneous 75

Chapter 17. Obliterative Otosclerosis 77

Chapter 18. The Learning Curve 81

Chapter 19. Special Conditions and Complications in Otosclerosis Surgery 83

Part VII. Atlas 91

Chapter 20. The Art of Stapes Surgery 93

Robert K. Jackler

Christine Gralapp, Chapter Illustrator

vi OtOsclerOsis: DiagnOsis, evaluatiOn, PathOlOgy, surgical techniques, anD OutcOmes

Chapter 21. Otosclerosis: Clinical Considerations 183

Richard James Wiet

Chapter 22. Obliterative Otosclerosis 195

Neil M. Sperling and Robert Vincent

Chapter 23. How to Do a Stapedotomy When the Facial Nerve Is Dehiscent 213

Thomas Linder and Christoph Schlegel-Wagner

Chapter 24. Revision Stapes Surgery: Technique of Neil M. Sperling 231

Neil M. Sperling

Chapter 25. Revision Stapedectomy: Technique of John C. Goddard 235

John C. Goddard and Audrey P. Calzada

Chapter 26. Causes of Failure of Stapedectomy 251

A. G. Pusalkar

Index 261

vii

List of Videos

1. Malleostapedectomy in Otosclerosis

Thomas Linder and Christoph Schlegel-Wagner

2. Stapedotomy in Persistent Stapedial Artery

Thomas Linder and Christoph Schlegel-Wagner

3. Full Stapedotomy Procedure

Neil M. Sperling

4. Laser-Assisted Superstructure Removal

Neil M. Sperling

5. Laser Rosette

Neil M. Sperling

6. Vein Graft Placement

Neil M. Sperling

7. Bucket-Handle Prosthesis Placement

Neil M. Sperling

8. Loop Piston Placement

Neil M. Sperling

9. Revision Stapedectomy

Neil M. Sperling

10. Revision Stapedectomy Using Double-Bend

Technique

John C. Goddard and Audrey P. Calzada

11. Persistent Stapedial Artery

John C. Goddard and Audrey P. Calzada

12. Facial Nerve Over Promontory

John C. Goddard and Audrey P. Calzada

13. Stapedectomy Surgery Using the Omniguide

Laser System

Richard James Wiet

14. Revision Stapedectomy with Adhesions Using

the Omniguide CO

Laser System

Richard James Wiet

15. Stapedectomy Using the Soft Clip Prosthesis

A. G. Pusalkar

Introduction

Worldwide, the number of patients suffering from

otosclerosis has declined considerably. Although

this is a cause for rejoicing, it places the modern-day

otologist in a unique predicament. It leaves him or

her with very little surgical experience in dealing

with otosclerosis. The patient who has undergone

surgery for otosclerosis many years ago and now

faces problems as a result of that surgery are among

the many challenges that the otologist of today will

need to face. The modern-day otologist will need to

overcome his or her own learning curve before being

able to perform the surgery reliably and deliver con-

sistently good results.

There are still quite a few nuances that need

to be learned if the otologist is to successfully and

effectively treat patients with otosclerosis. Our

book strives to help today’s otologist achieve that

goal. The references are limited to just a few. The

atlas section on the surgical procedures is provid-

ed by internationally acknowledged experts. Their

experience and techniques have been gleaned

through years of performing this amazingly de-

manding procedure and consistently delivering

excellent results. Each beautiful picture and illustra-

tion is worth a thousand words. Their surgical vid-

eos are priceless.

We hope that the current trends continue where

otosclerosis will just be a faded memory in the his-

tory of illnesses that affect humanity. But until then,

all otologists will still need to be familiar with all the

dimensions that the treatment of otosclerosis brings.

We thank the contributors for sharing their

valuable experience, their extraordinarily beautiful

illustrations, and their videos. We appreciate their

unselfishness and their graciousness. It is their hope,

as well as ours, that all who read this book will ben-

efit from it and as a result their patients will benefit

from it too.

Chris de Souza

Marcos V. Goycoolea

Neil M. Sperling

Part I

Basic Science

ChaPter 1

Pathology of Otosclerosis

Chris de Souza and Marcos V. Goycoolea

INTRODUCTION

Otosclerosis is primarily a disease of localized bone

remodeling.

It is thought to affect only the bony

capsule of the middle and inner ear selectively.

Otosclerosis is a process occurring in two phases:

(1) active phase as characterized by bone resorption

(spongiosis), and (2) phase of remission character-

ized by bone deposition (sclerosis).

It is a disease affecting enchondral bone of the

otic capsule characterized by disordered resorption

and deposition of bone.

An otosclerotic focus consists of areas of bone

resorption, new bone formation, vascular prolifera-

tion, and a connective tissue stroma.

AGE OF ONSET

It can range from 10 to 48 years of age, however, the

mean age of onset is commonly the age of 30.

DeJuan

in his study reported the onset of clini-

cal otosclerosis to be 28% between the ages of 18 and

21 years, 40% between 21 and 30, and 22% between

31 and 40.

PREVALENCE

The exact incidence remains unclear and next to

impossible to determine.

However, in one report autopsy studies con-

ducted by Konigsmark and Gorlin

revealed an inci-

dence of 5% to 18% of the general population.

Jahn and Vernick

report that 10% of Caucasians

have histologic otosclerosis, but only 1% of these

develop clinical manifestations of otosclerosis.

Many authors have noted that the incidence

of patients suffering from otosclerosis has declined

steeply in recent times.

RACE

There appears to be a definite racial predisposition.

Caucasians are more predisposed than Africans.

Asians too are far less affected than Caucasians,

and the prevalence in American Indians seems to be

extremely low across the continent.

GENDER

Shambaugh

noted a female preponderance in his

study. Otosclerosis is not a genetically sex-linked

characteristic disease. Thus, a ratio of 1:1 would

have been expected.

Hueb et al

reported a higher incidence of bilateral

otosclerosis in women than men. This prompted them

to believe that this would more likely cause women to

seek medical advice than men. This in turn could likely

explain the gender disparity. On the other hand, endo-

crinological factors predisposing to the appearance of

otosclerotic foci is a possibility to be considered.

4 OTOSCLEROSIS: DIAGNOSIS, EVALUATION, PATHOLOGY, SURGICAL TECHNIQUES, AND OUTCOMES

OTOSCLEROSIS AND PREGNANCY

There are many reports that associate the onset of

hearing loss caused by otosclerosis and the onset

of pregnancy. Shambaugh

found that in an analy-

sis of 475 female patients suffering from otosclerosis

that 50% suffered from hearing impairment with the

onset of pregnancy. Although he and many authors

note a correlation between the onset of hearing loss

following pregnancy, they are not clear on why or

how this occurs. As mentioned earlier, endocrino-

logic factors have been suspected for this occurrence.

TYPES OF OTOSCLEROSIS

1. Histologic otosclerosis

2. Fenestral otosclerosis

3. Cochlear otosclerosis

4. Malignant otosclerosis

5. Far advanced otosclerosis

Histologic Otosclerosis

(Figures 1–1 and 1–2)

Histologic otosclerosis is a finding on microscopic

examination of temporal bones. The location of the

otosclerotic changes is such that the patient suffers

no symptoms related to the otosclerosic changes.

Therefore, it generally does not involve the stapes

bone, the stapediovestibular joint, or the cochlear

endosteum. It is therefore asymptomatic.

Fenestral Otosclerosis

This refers to an otosclerotic lesion that involves

the stapes bone and/or the stapediovestibular joint.

This in turn causes a conductive hearing loss. This is

Figure 1–1. Section of human temporal bone demonstrating “his-

tologic otosclerotic” focus. O = “histologic” otosclerotic focus; SF =

stapedial footplate; C = cochlea; V = vestibule. Courtesy of Univer-

sity of Minnesota temporal bone collection. Kindly contributed by

Dr. Cureoglu and Dr. Paparella.

PATHOLOGY OF OTOSCLEROSIS 5

the most common site of involvement representing

81 to 95% of cases.

Cochlear Otosclerosis (Figure 1–3)

Cochlear otosclerosis is a term used in cases in which

the otosclerotic lesion invades the cochlear endos-

teum and is usually reserved for the occurrence of

pure sensorineural hearing loss due to otosclerosis

without any conductive component.

“Malignant” (Obliterative) Otosclerosis

This is defined as severely active otosclerosis involving

both oval and round windows and most of the bony

labyrinth and is manifested initially by mixed hear-

ing loss, which then relentlessly progresses to severe

profound sensorineural hearing loss. Both windows

are obliterated by the otosclerotic focus. Lamellar new

bone is seen in the inner ear of such patients.

Far Advanced Otosclerosis (FAO)

Far advanced otosclerosis is defined as no measur-

able air or bone conduction or air conduction no bet-

ter than 95 dB and bone conduction at 55 dB to 60 dB

at one frequency only.

A negative Rinne’s test result with a 256 Hz

magnesium tuning fork is the best way to separate a

FAO sensorineural hearing loss from sensorineural

hearing losses of other causes.

SITES OF INVOLVEMENT OF THE

TEMPORAL BONE BY OTOSCLEROSIS

IN ORDER OF FREQUENCY

1. Commonly seen anterior to the oval window

2. The round window niche (Figures 1–4 and 1–5)

3. Posterior to the round window

4. Posterior wall of the internal auditory canal

Figure 1–2. Magnified view of histologic otosclerosis. O = otoscle-

rotic focus; V = vestibule; SF = stapedial footplate. Courtesy of Uni-

versity of Minnesota temporal bone collection. Kindly contributed

by Dr. Cureoglu and Dr. Paparella.

Figure 1–3. Histopathology section of human temporal bone

demonstrating cochlear otosclerosis. O = otosclerotic focus; C =

cochlea deformed by the otosclerosis; V = vestibule; 2 = saccule;

1 = utricle; SF = stapes footplate; FN = facial nerve. Courtesy of Uni-

versity of Minnesota temporal bone collection. Kindly contributed

by Dr. Cureoglu and Dr. Paparella.

Figure 1–4. HP section demonstrating otosclerotic focus oblit-

erating the round window. O = otosclerotic focus; C = cochlea;

NB = new bone formation. Courtesy of University of Minnesota

temporal bone collection. Kindly contributed by Dr. Cureoglu and

Dr. Paparella.

PATHOLOGY OF OTOSCLEROSIS 7

5. Around the cochlear aqueduct

6. Semicircular canals

7. Totally within the stapedial footplate

HISTOPATHOLOGY OF OTOSCLEROSIS

The otic capsule itself undergoes very little remod-

eling. The otic capsule contains small regions of

immature cartilaginous tissue called the “globuli

interossei.” This may be the loci of the earliest lesions

of otosclerosis.

Otosclerosis is characterized by the following:

1. Bone resorption

2. New bone formation

3. Vascular proliferation

4. Connective tissue stroma.

The very first stage of otosclerosis is resorption

of enchondral bone around blood vessels.

Second: This results in enlargement of perivas-

cular spaces. Vascular spaces become wider. This is

the initial stage characterized by diffuse or patchy

demineralization that coincides with preotosclerotic

lesions.

Third: This is then followed by deposition of

immature (woven) bone.

Fourth: Resorption and deposition of imma-

ture bone occurs continuously within an otosclerotic

focus with production of more mature (lamellar) bone.

Figure 1–5. HP section demonstrating otosclerotic focus near

round window niche. O = otosclerotic focus; RWM = round win-

dow membrane; SC = Semicircular canal. Courtesy of University

of Minnesota temporal bone collection. Kindly contributed by Dr.

Cureoglu and Dr. Paparella.