Color Atlas of EndoOtoscopy Examination Diagnosis Treatment

Despite the many advances in diagnostic technologies and imaging modalities in recent years, otoscopy remains the first diagnostic option in the diagnosis of otologic disease. This is an easytoconsult book for residents and specialists, featuring brilliant diagnostic images from the newest generation of endoscopic otoscopes. Written by a renowned team of experts with 30 years of experience, this book helps readers obtain proficiency in otoscopy and in the interpretation of findings. Readers will learn what clinical consequences the diagnoses may have through case examples and treatment suggestions.

Color Atlas of Endo-Otoscopy

Exam inat ion–Diagnosis–Treatm ent

Piacenza and Rom e, Italy

Alessan dra Ru sso, MD

Otologist and Skull Base Surgeon

Gruppo Otologico

Piacenza and Rom e, Italy

An ton io Caru so, MD

Otologist and Skull Base Surgeon

Librar y of Con gress Cat alogin g-in -Pu blicat ion Dat a is available from the

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Preface vii

Contributors viii

1 Methods of Otoscopy 1

2 The Norm al Tym panic Mem brane 7

2.1 Anatom y 8

2.2 Histology 11

2.3 Physiology 11

3 Diseases A ecting the External Auditory Canal 13

3.1 Exostosis and Osteom as 14

3.1.1 Surgery for Exostosis and Osteom a: Canalplast y 21

3.2 External Auditory Canal Inflam m atory Diseases 25 3.2.1 Eczem a 25

3.2.2 Otitis Externa 25

3.2.3 Foruncolosis 27

3.2.4 Otom ycosis 27

3.2.5 Myringitis and Meatal Stenosis 29

3.2.6 Surgery for Postinflam m atory Stenosis of the External Auditory Canal 33

3.3 Cholesteatom a of the External Auditory Canal 37

3.4 Pathologies Extending to the External Audit ory Canal 40

3.4.1 Carcinoid Tum ors 40

3.4.2 Histiocytosis X 41

3.4.3 Meningiom as 42

3.4.4 Facial Nerve Tum ors 44

3.4.5 Lower Cranial Nerves Schw annom a 46

3.4.6 Other Pathologies 47

3.5 Tem poral Bone Fractures 49

3.6 Carcinom a of the External Audit ory Canal 50

4 Otitis Media 65

4.1 Secret ory Otitis Media (Otitis Media w ith E usion) 66

4.2 Secretory Otitis Media Secondary to Neoplasm 69

4.3 Acute Otitis Media 74

5 Cholesterol Granulom a 75

6 Atelectasis, Adhesive Otitis Media 81

7 Noncholesteatom atous Chronic Otitis Media 93

7.1 General Characterist ics of Tym panic Mem brane Perforat ions 94

7.2 Posterior Perforations 94

7.3 Anterior Perforations 97

7.4 Inferior Perforat ions 99

7.5 Subtotal and Total Perforat ions 100

7.6 Posttraum atic Perforations 102

7.7 Perforations Com plicated or Associated w ith Other Pathologies 104

7.8 Tym panosclerosis 107

7.8.1 Tym panosclerosis Associated w ith Tym panic Mem brane Perforation 107

7.8.2 Tympanosclerosis w ith Intact Tympanic Mem brane 110

7.9 Principles of Myringoplast y 112

8 Chronic Suppurative Otitis Media w ith Cholesteatom a 117

8.1 Epit ym panic Retraction Pocket 118 8.2 Epit ym panic Cholesteatom a 120

v

8.3 Mesot ym panic Cholesteatom a 129

8.4 Cholesteatom a Associated w ith Atelectasis 134

8.5 Cholest eat om a Associat ed w it h Com plicat ions 136

8.6 Surgical Treatm ent of Cholesteatom a: Individualized Technique 139

8.6.1 Canal Wall Up (Closed) Tym panoplasty 139

8.6.2 Canal Wall Dow n (Closed) Tym panoplast y 145

8.6.3 Modified Bondy’s Technique 153

9 Congenital Cholesteatom a of the Middle Ear 159

10 Petrous Bone Cholesteatom a 167

10.1 Surgical Managem ent 184

10.1.1 The Transotic and Modified Transcochlear Approaches 184

10.1.2 Problem s in Surgery 193

11 Tem poral Bone Paragangliom as 195

11.1 Clinical Presentation of Tym panic and Tym panom astoid Paragangliom as 197

11.2 Clinical Presentation of Tym panojugular Paragangliom as 197

11.3 Im aging Characteristics 197

11.3.1 Tym panojugular Paragangliom as 197

11.4 Classification: The Modified Fisch Classification System for TJP 198

11.5 Class A: Tym panic Paragangliom as 205

11.5.1 Surgical Managem ent 208

11.6 Class B: Tym panom astoid Paragangliom as 213

11.6.1 Surgical Managem ent 218

11.7 Class C: Tym panojugular Paragangliom as 221

11.7.1 Surgical Managem ent 236

11.8 Type A Infratem poral Fossa Approach 237

11.8.1 Surgical Technique 237

12 Rare Retrot ym panic Masses 241

12.1 Di erential Diagnosis of Retrot ym panic Masses 242

12.2 Meningiom a 242

12.3 Lower Cranial Nerves Neurinom a 247

12.4 Chondrosarcom a of the Jugular Foram en 249

12.5 Facial Nerve Tum ors 250

12.6 Aberrant Carotid Artery 260

12.7 Internal Carotid Artery Aneurysm 261

12.8 High Jugular Bulb 262

13 Meningoencephalic Herniation 267

13.1 Surgical Managem ent 276

13.1.1 Transm astoid Approach 276

13.1.2 Transm astoid Approach w ith Minicraniotom y 278

13.1.3 Subtotal Petrosectom y 279

14 Postsurgical Conditions 285

14.1 Myringotom y and Insertion of Vent ilation Tube 286

14.2 Stapes Surgery 290

14.3 Myringoplast y 293

14.3.1 Failures and Com plications 297

14.4 Tym panoplast y 301

14.4.1 Canal Wall Up (Closed) Tym panoplasty 301

14.4.2 Canal Wall Dow n (Open) Tym panoplast y 316

14.4.3 Meatoplast y, Blind-Sac Closure of the External Auditory Canal 327

14.5 Hearing Im plants 329

References 331

Index 337 Contents

Despite advances in diagnostic techniques and im aging m odalities,

otoscopy rem ains the cornerstone in the diagnosis of otologic

diseases Every otolaryngologist, pediatrician, or even general

practitioner dealing w ith ear diseases should have a good know

l-edge of otoscopy This atlas is based on 30 years of experience in

Gruppo Otologico in the treatm ent of otologic and neurotologic

disorders, w ith m ore than 32,000 surgical operations and 300,000

consultations It presents a vast collection of otoscopic view s of a

variety of lesions that can affect the ear and tem poral bone Many

exam ples are given for each disease so that the reader becom es

acquainted w ith the variable presentations each pathology can

have

While otoscopy alone can establish the diagnosis in som e cases,

param eters such as history or audiological and neuroradiological

evaluation are required in others An im portant aspect of this atlas

is that it juxtaposes, w hen appropriate, the clinical picture,

radio-logical diagnosis, and intraoperative ndings w ith the otoscopic

ndings of the patient Needless to say, every patient should be

considered as a w hole, and in som e particular cases, the otoscopic

ndings m ight only be the “tip of the iceberg.” Otalgia, otorrhea,

and granulations in the external auditory canal are m anifestations

of otitis externa, but w hen they persist, particularly in the elderly,

they should arouse suspicion of m alignancy Otitis m edia w ith

effusion can be a sim ple disease w hen seen in children, w hereas

unilateral persistent otitis m edia w ith effusion in an adult m ay be

the only sign of a nasophar yngeal carcinom a A sm all attic

perfo-ration in the presence of facial nerve paralysis and sensorineural

hearing loss m ay be all that is seen in a giant petrous bone

cholesteatom a The m anifestation of an aural polyp can vary from

a m ucosal polyp associated w ith chronic suppurative otitis m edia

to the m uch less com m on but m ore dangerous tem poral bone

paragangliom a A sm all retrot ym panic m ass m ay represent an

anom alous anatom y such as a high jugular bulb or an aberrantcarotid artery It m ay also represent frank pathology such as facialnerve neurom a, congenital cholesteatom a, or even en-plaque

m eningiom a

In each chapter, a surgical sum m ary that lists the differentapproaches for the m anagem ent of the pathology dealt w ith isprovided Throughout the book, em phasis is on how the otoscopicview and the clinical picture m ay affect the choice of treatm ent andthe surgical technique

At the end of this atlas, a chapter on postsurgical conditions ispresented The presence of previous surgery poses special dif -culties because of the distorted anatomy Moreover, the otologistshould be able to distinguish between w hat is considered to benorm al postsurgical healing and com plications that need furtherintervention

Our goal is to offer an easy-to-consult book for residents,specialists, and general practitioners So, this rst-step approach

to patients w ith otologic diseases can open a w ider view oncom plete know ledge of otology, neurotology, skull base pathologyand surgery, and neuroradiology

Drs Russo, Taibah, Caruso, and Gianluca Piras, a new youngcolleague w ho has been working w ith us for the past year, helped toaccom plish this w ork w ith their active and enthusiastic partici-pation A special thank goes to the other m em bers of GruppoOtologico, for their contribution in the realization of this book:

Drs Piccirillo, Lauda, Giannuzzi, and Prasad

The authors would like to thank Mr Stephan Konnry at Thiem ePublishers for his excellent cooperation and help Thanks also go toPaolo Piazza, neuroradiologist, for his continuous cooperation and

to Fernando Mancini for the illustrations included in the book

Mario Sanna , MD

vii

An ton io Caru so, MD

Otologist and Skull Base Surgeon

Gruppo Otologico

Piacenza and Rom e, Italy

An n alisa Gian n u zzi, MD, Ph D

Otologist and Skull Base Surgeon

Gruppo Otologico

Piacenza and Rom e, Italy

Loren zo Lau da, MD

ENT and Skull Base Surgeon

Gruppo Otologico

Piacenza and Rom e, Italy

Fer n an do Man cin i, MD

ENT and Skull Base Surgeon

Piacenza and Rom e, Italy

Sam path Ch an dra Prasad Rao, MS, DNB, FEB-ORLHNSENT and Skull Base Surgeon

Gruppo OtologicoPiacenza and Rom e, Italy

Alessan dra Ru sso, MDOtologist and Skull Base SurgeonGruppo Otologico

Piacenza and Rom e, Italy

Mario San n a, MDProfessor of OtolaryngologyDepartm ent of Head and Neck SurgeryUniversity of Chieti

Chieti, ItalyDirectorGruppo OtologicoPiacenza and Rom e, Italy

Hirosh i Su n oseDepartm ent of OtolaryngologyMedical Center East

Tokyo Wom en’s Medical UniversityTokyo, Japan

Abdelkader Taibah , MDNeurosurgeon, Otologist, and Skull Base SurgeonGruppo Otologico

Piacenza and Rom e, Italy

Chapter 1 Methods of Otoscopy

1 Methods of Otoscopy

Abst ract

This chapter explains how w e routinely perform otoscopy With

the help of a m icroscope and endoscope, each clinical condition

can be easily studied, recorded, and prin ted for a deeper analysis

Perform ing a proper otoscopy is the first step for the correct

m anagem ent of the w hole pathology of the tem poral bone and

skull base

Keywords: otoscopy, m icroscope, endoscope, instant photography

A prelim inar y exam ination is perform ed using a head m irror or

an otoscope

For proper otoscopy, the external auditory canal should becleaned Few instrum ents are used for this step, nam ely, auralspeculi of di erent sizes, a Billeau ear loop, Hartm an auricularforceps, and suction tips ( Fig 1.1) In cases w ith a history ofrecurrent otitis, w e prefer to clean the ear w ith the aid of a

The use of a rigid 0-degree 6-cm endoscope ( Fig 1.3)

con-nected to a video system enables the patient to see the pthology

involving his/her ear ( Fig 1.4) The rigid 30-degree endoscope

allow s evaluation of attic retraction pockets, the extent of

w hich cannot always be determ ined using the m icroscope or the

0-degree endoscope ( Fig 1.5)

Instant photography has also been used in the operating room

A copy of the im portant steps of the operation is given to the

patient w hile another copy is kept in the patient’s chart The

patient is also photographed during the follow -up visit Thus, for

each patient pre-, intra-, and postoperative photographic

docu-m entation is obtained

During the past years, a cam era m ounted to the endoscope w asused for obtaining photos ( Fig 1.6); nowadays a digital custom -ized system is used for collecting pictures on a laptop storage,

w ith the possibilit y of collect otoscopic im ages on a patient’schart So, the advent of com puterized system s ( Fig 1.7) allow svirtual storaging of all the photos or videos, w ith the advantage

of reducing tim es of acquisition, m odification, and deletion therm ore, a deeper clinical analysis could be assessed

Fur-In all the cases, the exam iner sits to the side of the patient

w hose head is slightly tilted toward the contralateral side Theexam iner holds the cam era attached to the endoscope w ith hisright hand With the ring and m iddle finger of the left hand, the

Fig 1.3 A rigid 0-degree 6-cm endoscope

Fig 1.4 The endoscope can be connected to avideo system such as this

Methods of Otoscopy

3

Fig 1.5 A series of rigid endoscopes.

Fig 1.6 A setup used in past years for photographing patients

Fig 1.7 A modern setup of computerized systems for digital collection

of patients’ photos

Methods of Otoscopy

exam iner pulls the patient’s auricle backw ard and outwards

to straighten the external auditor y canal The endoscope is

advanced over the index finger of the exam iner’s left hand into

the patient’s external auditory canal In this m anner, any undue

injury to the external auditory canal is prevented ( Fig 1.8)

Fig 1.8 Examination of a patient in progress

Methods of Otoscopy

5

2 The Norm al Tym panic Mem brane

Abst ract

The norm al t ym panic m em brane is thin, sem i-transparent,

pearly gray colored, and consists of three layers from the outside

to the inside (epithelial, fibrous, and m ucosal) The tym panic

m em brane not only acts as a sound wave transducer to the

ossic-ular chain, but also has a protective function to the m iddle ear

and serves as a sound am plifier It is conventionally divided into

four quadrants from two perpendicular lines passing through

the um bo (anterosuperior, anteroinferior, posterosuperior,

posteroinferior)

Keywords: t ym panic m em brane, tym panic layers, ossicular chain,

tym panic quadrants

2.1 Anatom y

The tym panic m em brane form s the m ajor part of the lateral w all

of the m iddle ear (see Fig 2.1, Fig 2.2, Fig 2.3) It is thin,

resistant, sem i-transparent, has a pearly gray color, and is

cone-like The apex of the m em brane lies at the um bo, w hich

corre-sponds to the low est part of the handle of the m alleus Most of

the m em brane circum ference is thickened to form a ginous ring, the t ym panic annulus, w hich sits in a groove in the

fibrocartila-t ym panic bone called fibrocartila-the fibrocartila-tym panic sulcus The fibrocarfibrocartila-tilaginousring is deficient superiorly This deficiency is know n as the notch

of Rivinus The anterior and posterior m alleolar folds extend fromthe short process of the m alleus to the t ym panic sulcus, thusform ing the inferior lim it of the pars flaccida of Shrapnell's

m em brane

The m em brane form s an obtuse angle w ith the posterior wall

of the external auditory canal It also form s an acute angle w iththe anterior w all of the canal It is im portant to respect this acuteangulation in the m yringoplasty operation to m aintain as m uch

as possible the vibratory m echanism of the tym panic m em braneand hence ensure m axim um hearing im provem ent (seeFig 2.4, Fig 2.5, Fig 2.6, Fig 2.7, Fig 2.8)

The external surface of the tym panic m em brane is innervated

by the auriculotem poral nerve and the auricular branch of thevagus nerve, w hereas the inner surface is supplied by Jacobson'snerve, a branch of the glossophar yngeal nerve

The blood supply is derived from the deep auricular and rior t ym panic arteries Both are branches of the m axillary artery

ante-C O 8

3 2 1

4 R

7

A P

T

6

5 I

Fig 2.1 Right ear Normal t ympanic membrane

1, pars flaccida; 2, short process of the malleus;

3, handle of the malleus; 4, umbo; 5, supratubalrecess; 6, tubal orifice; 7, hypotympanic air cells;

8, stapedius tendon; c, chorda t ympani; I, incus;

P, promontory; o, oval window; R, round dow; T, tensor tympani; A, annulus

win-The Norm al Tym panic Mem brane

8 O 9

proc-P.S.

A.S.

P.I.

A.I.

Fig 2.3 Right ear Division of the tympanic membrane into four

quadrants: AS, anterosuperior; AI, anteroinferior; PS, posterosuperior;

PI, posteroinferior This division facilitates the description of different

pathologic affections of the tympanic membrane

Fig 2.4 Left ear Normal t ympanic membrane Note the acute angleformed between the tympanic membrane and the anterior wall of theexternal auditory canal The pars tensa with the short process of thehandle of the malleus, the umbo, the cone of light, the annulus, andthe pars flaccida are seen Note also the presence of early exostosis inthe superior wall of the external auditory canal

The Norm al Tym panic Mem brane

9

Fig 2.5 Right ear Normal t ympanic membrane In this case, the drum

is very thin and transparent The handle and short process of the

malleus as well as the umbo and cone of light are well visualized

Through the transparent tympanic membrane, the region of the oval

window, the long process of the incus, the posterior arc of the stapes,

the incudostapedial joint, the round window, and the promontory can

be distinguished Anteriorly, at the region of the Eustachian tube, the

tensor tympani canal and the supratubaric recess can be observed

Fig 2.6 Left ear Normal tympanic membrane The handle of themalleus and cone of light are well visualized through the tympanicmembrane; the promontory, the area of the round window, and theair cells in the hypotympanum can be appreciated The pars flaccida isvisualized superior to the short process of the malleus

Fig 2.8 Left ear A normal tympanic membrane that is slightly thinned

in the anterior quadrant and moderately thickened posteriorly

Fig 2.7 Right ear Normal tympanic membrane The drum, however,

is slightly thickened with an accentuated capillary network along the

handle of the malleus The increased thickness of the tympanic

membrane obscures all the structures in the middle ear

The Norm al Tym panic Mem brane

2.2 Histology

The t ym panic m em brane consists of three layers: an outer

epi-thelial layer continuous w ith the skin of the external auditory

canal, a m iddle fibrous layer or lam ina propria, and an inner

m ucosal layer continuous w ith the lining of the tym panic cavit y

The epiderm is or outer layer is divided into the stratum

cor-neum , the stratum granulosum , the stratum spinosum , and the

stratum basale, w hich is the deepest layer that rests on the

base-m ent base-m ebase-m brane

The lam ina propria is characterized by the presence of collagen

fibers In the pars tensa, these fibers are arranged in tw o basic

layers: an outer radial layer that originates from the inferior part

of the handle of the m alleus and inserts in the annulus, and an

inner circular layer that originates prim arily from the short

proc-ess of the m alleus Such a distinct arrangem ent, however, is

absent in the pars flaccida

The m ucosal layer is form ed m ainly of a sim ple cuboidal or

col-um nar epithelicol-um The free surface of the cells possesses ncol-um ous m icrovilli

er-2.3 Physiology

The external ear has a protective function against the m iddle earand serves as a sound am plifier The external ear not onlychanges the perception of sound am plifying som e frequencies,but also increases the directionalit y, due to the di raction of thesound w aves on the entire head and external ear, in particularthe ear pavilion The m axim um am plification is ~20 dB for fre-quencies between 2 and 3 kHz The tym panic m em brane acts as asound wave transducer to the ossicular chain

The Norm al Tym panic Mem brane

11

Chapter 3

Diseases A ecting the External

Auditory Canal

3.2 External Auditory Canal

3.3 Cholesteatom a of the External

3.4 Pathologies Extending to the

3.6 Carcinom a of the External

3 Diseases A ecting the External Auditory Canal

Abst ract

Pathologies a ecting the external auditory canal (EAC) are a w ide

spectrum of diseases that include: bony neoform ations of the

EAC (exostosis and osteom as), inflam m atory diseases (external

otitis, otom ycosis, and inflam m atory stenosis of the EAC),

choles-teatom a of the EAC, benign tum ors of the ear and skull base

extending to the EAC (carcinoid tum or, m eningiom as, facial nerve

tum ors, etc.), tem poral bone fract ures, and carcinom a of the EAC

Otoscopy is fundam ental for the recognition of each clinical

con-dition Analysis of patient clinical history and sym ptom s are also

of utm ost im portance to decide the proper therapeutic m

anagem ent, w hich is di erent depending on the pathology For exaanagem

-ple, in case of exostosis and osteom as occluding the EAC a

canalplast y is indicated, as w ell as a surgical treatm ent is the

m ainstay for m ost of the benign and m align tum ors involving the

EAC Further radiological exam inations (CT and MRI scans) are

indicated in the suspect of a tum or

Keywords: external auditory canal, exostosis, osteom as, otitis

externa, otom ycosis, cholesteatom a, m eningiom a, facial nerve

tum or, tem poral bone fract ures, squam ous cell carcinom a

3.1 Exostosis and Osteom as

Exostosis are defin ed as n ew bony grow th s in th e osseous

port ion of th e extern al auditor y canal (EAC) Th ey are usually

m ultiple, bilateral, an d are com m on ly sessile Th ey var y in

sh ape, being eith er roun d, ovoid, or oblong Th e con dit ion iscaused by periostitis secon dar y to exposure to cold w ater Th isexplain s th e h igh in ciden ce of exostoses am ong divers andcold-w ater bath ers Histologically, th ey are form ed from paral-lel layers of n ew ly form ed bon e It is postulated th at th e peri-osteum stim ulates an osteogen ic reaction w ith each exposure

to cold w ater, causing th is strat ification W h en exostoses are

sm all, th ey are asym ptom atic Large lesion s, h ow ever, canocclude th e EAC and lead to con ductive h earing loss or reten -tion of w ax an d debris w ith subsequen t ot itis extern a In suchcases, an d in cases in w h ich a h earing aid is to be fit ted, sur-gical rem oval of exostoses is in dicated In som e cases, surger y

is tech n ically di cult an d special care is taken to preser ve th eskin of th e EAC Oth er structures at risk are th e t ym pan ic

m em bran e an d ossicular ch ain m edially, th e tem porom an ular join t an teriorly, an d th e th ird segm en t of th e facial n er veposteroin feriorly

dib-Osteom a is a true benign neoplasm of the bone of the EAC, ally unilateral and pedunculated Histologically, it can be di er-entiated from exostosis by the absence of the lam inated grow thpattern

usu-According to the extent of both diseases, w e developed a fication for EAC stenosis, w hich is based m ainly on the am ount oftym panic m em brane otoscopically visible ( Table 3.1; Fig 3.1,Fig 3.2, Fig 3.3, Fig 3.4, Fig 3.5, Fig 3.6, Fig 3.7,Fig 3.8, Fig 3.9, Fig 3.10, Fig 3.11, Fig 3.12, Fig 3.13,Fig 3.14, Fig 3.15, Fig 3.16, Fig 3.17, Fig 3.18,Fig 3.19, Fig 3.20)

classi-Table 3.1 Grading of external auditory canal stenosis

Grade Severit y Otoendoscopic finding Radiological finding* Descriptive figures

0 No stenosis All four quadrants of the pars tensa are

Table 3.1 Grading of external auditory canal stenosis (continued)

Grade Severit y Otoendoscopic finding Radiological finding* Descriptive figures

V Total stenosis None of the quadrants are visible

0% of the pars tensa area is visible

90–100% narrowing of EAC

*The degree of stenosis is calculated as a percentage of the maximum measurement available of the lesion against the maximum diameter of the EAC

in axial and coronal cuts

Abbreviation: EAC, external auditory canal

Diseases A ecting the External Auditory Canal

15

Fig 3.3 Right ear Exostosis originating from the inferior and

posteriors wall of the external auditory canal According to our

classification, this is a Grade I stenosis This case should be simply

followed up

Fig 3.4 Left ear Bilateral Grade II stenosis of the external auditorycanal for exostosis of the anterior wall The tympanic membrane isviewable on its posterior quadrants In this type of case, it is useful tophotograph both ears for further follow-up within 1 to 2 years

Fig 3.2 Left ear Small asymptomatic exostosis originating from theanterior wall of the external auditory canal

Fig 3.1 Right ear Small exostosis originating from the superior wall of

the external auditory canal A hump on the anterior wall precludes

visualization of the anterior–inferior quadrant of the tympanic

membrane

Diseases A ecting the External Auditory Canal

Fig 3.5 Right ear Same patient as in Fig 3.4 Bilateral Grade II

stenosis of the external auditory canal for exostosis of the anterior

wall The t ympanic membrane is viewable on its posterior quadrants

In this type of case, it is useful to photograph both ears for further

follow-up within 1 to 2 years

Fig 3.6 Right ear Grade III stenosis for exostosis originating from theanterior and posterior walls of the external auditory canal Less than 50%

of the tympanic membrane is viewable The patient complains of hearingloss and frequent episodes of otitis externa secondary to retention ofwater and debris inside the canal A canalplasty under local anesthesia isindicated to restore the size of the external auditory canal

Fig 3.7 Right ear Grade IV stenosis Less than 20% of the tympanic

membrane is visible The occurrence of conductive hearing loss is high

in this type of stenosis, so surgery is recommended

Fig 3.8 This figure and Fig 3.9 correspond to computed raphy (CT) scans (axial and coronal cuts), which show exostosis fromeach wall of the external auditory canal of the patient in Fig 3.6 andFig 3.7 These bony lesions show radiopacit y A preoperative CTscan is not fundamental but could be useful to check the amount ofbone removal anteriorly (avoiding the opening of the temporoman-dibular joint: green arrow), posteriorly (avoiding the opening of themastoid air cells or an injury of the third portion of the facial nerve:

tomog-yellow arrows), and medially (avoiding an injury of the tympanicmembrane and of the ossicles)

Diseases A ecting the External Auditory Canal

17

Fig 3.9 Same patient as in Fig 3.8 Computed tomography (CT)

scans (axial and coronal cuts), which show exostosis from each wall of

the external auditory canal These bony lesions show radiopacit y A

preoperative CT scan is not fundamental but could be useful to check

the amount of bone removal anteriorly (avoiding the opening of the

temporomandibular joint), posteriorly (avoiding the opening of the

mastoid air cells or an injury of the third portion of the facial nerve),

and medially (avoiding an injury of the t ympanic membrane and of the

ossicles: blue arrows)

Fig 3.10 Right ear Complete stenosis of the external auditory canal.The t ympanic membrane is not visible As a first evaluation of

complete stenosis is important to ensure the bony consistency ofthese lesions through a gentle pressure with a hook The patientusually does not refer pain after the maneuver A CT scan is indicated

in this case to check the condition of the middle ear

Fig 3.11 Right ear Osseous neoformation of the external auditory

canal In this case, given the pedunculated narrow base, an osteoma is

a more probable diagnosis This was confirmed by pathological

examination of the removed specimen Ample bone removal is

performed in such cases to avoid recurrence

Fig 3.12 Same patient CTscan (axial cut) shows a pedunculated bonylesion of the anterosuperior wall of the external auditory canal

Diseases A ecting the External Auditory Canal

Fig 3.13 Left ear Exostoses of the posterior and anterior walls of the

external auditory canal and osteoma of anterosuperior wall The

lesions allow only a limited view of the tympanic membrane (Grade III

stenosis) In this case, regular follow-up is necessary because further

growth of the lesions could lead to accumulation of debris and

cerumen, necessitating surgical intervention

Fig 3.14 Left ear Osteomas of the superior wall of the externalauditory canal The pars flaccida of the tympanic membrane is notvisible

Fig 3.15 Right ear Same patient as in Fig 3.14 Osteomas and

exostoses allow visualization of the tympanic membrane only in the

central part

Fig 3.16 Right ear Osteoma occluding the external auditory canalwith accumulation of wax and hearing loss The pedicle of the lesion(anterior wall of the external auditory canal) is not well recognizable

Surgery is indicated in such case

Diseases A ecting the External Auditory Canal

19

Fig 3.17 Left ear Exostoses with Grade III stenosis of the external

auditory canal A small perforation of the anteroinferior quadrant of

the tympanic membrane is present In this case, surgery includes a

canalplasty combined with a myringoplasty

Fig 3.18 Left ear Obstructing exostosis of the external auditory canalresulting in otitis externa due to accumulation of squamous debrisinside the canal Surgery is essential both to avoid the formation ofcholesteatoma and to improve hearing

Fig 3.19 Left ear Exostosis of the external auditory canal with a polyp

that occludes the meatus Local therapy is indicated In case of no

response, a CT scan is mandatory to exclude pathology affecting the

middle ear and/or the mastoid

Fig 3.20 Left ear Exostoses of the external auditory canal with severestenosis (Grade III) This condition facilitates retention of ear wax withthe onset of conductive hearing loss

Diseases A ecting the External Auditory Canal

3.1.1 Surgery for Exostosis and

Osteom a: Canalplast y

Even if usually asym ptom atic, exostosis and osteom a m ay grow

occluding the EAC Surgery is indicated in case of obstructing

stenosis (w ith or w ithout hearing loss), or in case of frequent

oti-tis externa w here it is necessary to fit a hearing aid In cases

w here sym ptom s are m inim al, it is useful to photograph the ear

for further follow -up In surgery, preservation and proper

replacem ent of the m eatal skin is im portant to prevent

postope-rative scarring and stenosis Osteom a can be rem oved w ith a

cur-ette How ever, if osteom a recurs, w ide drilling of the bone around

its base is indicated

In lim ited cases in w hich w ide exposure is not required (i.e.,

sm all osteom a), a transcanal approach could be used The m eatal

skin is incised through an ear speculum and the skin over the

osteom a is elevated The osteom a is then rem oved w ith either a

curette or a burr

Surgical Steps

1 Retroauricular incision is used in m ost of the cases since this

approach is w ider and safer than the transcanal approach The

initial steps of surger y including skin incision, harvesting the

tem poralis fascia, and soft tissue incision

2 In case of severe exostosis, there is no consistent landmark inthe EAC since the tym panic m em brane is obscured ( Fig 3.21)

If there is any space m edially, the skin is detached from thebone and to push m edially toward the tym panic m em brane

The skin m ay be protected w ith an alum inum sheet w ith/w out a sm all piece of cottonoid beneath the sheet

ith-3 If the space m edial to bony protrusions is insu cient to tain the detached skin, the skin covering the bony overhang isdetached and folded toward the contralateral wall Protectingthe skin w ith an alum inum sheet, a part of the protrusion isdrilled m edially ( Fig 3.22)

con-4 The m eatal skin covering another protrusion is detached, andthe flap is then folded tow ard the space created by the drill-ing The alum inum sheeting is repositioned between the bonywall and the m eatal skin flap, and the bony protrusion is par-tially drilled m edially

5 After partly drilling the second bony protrusion, the m eatalskin is repositioned, and the first protrusion is drilled further

In this w ay, the canal is gradually drilled from lateral to

im portant to restrict the area of drilling around the m eatal

Fig 3.21 The tympanic membrane is obscured

in severe stenosis (no landmarks)

skin until the t ym panic m em brane is su ciently visualized.

Position of the tym panic m em brane should be verified fromtim e to tim e by replacing the m eatal skin

7 If protrusion still lim its view of the tym panic m em brane, the

anterior canal w all m ay be drilled to help visualize the m em brane, taking care not to dam age the tem porom andibularjoint anteriorly ( Fig 3.23) However, accidental exposure ofthe tem porom andibular joint is better than dam age of thefacial ner ve Posterior canal should not be drilled too m ediallybefore verifying the area of drilling

-8 Using the m eatal skin elevator (# 2), quantity of bone to be

drilled and distance from the annulus are estim ated from tim e

to tim e

9 Rem oval of the final bony overhang m ay be conducted w ith a

sm all curette ( Fig 3.24) If the drill is used, care should betaken not to touch the short process of the m alleus w ith aburr

10.The exposed canal bone should be covered w ith the tem lis fascia Longitudinal plastic cuts m ay be m ade in the m eatalflap to assure intim ate lining on the bone Lateral m eatal skin

pora-m ay also be cut longitudinally

11.The external ear canal is packed w ith Gelfoam (see Fig 3.25,

Fig 3.26, Fig 3.27, Fig 3.28, Fig 3.29, Fig 3.30)

TMJ

Fig 3.23 Drilling of the anterior wall TMJ, temporomandibular joint Fig 3.24 Removal of the final bone overhang

Fig 3.25 Example of canalplast y Right side.Exostoses of the anterior and posteroinferiorwalls of the external auditory canal and osteo-mas of the superior and posterior walls Aretroauricular approach has been performedand the meatal skin has been incised

Diseases A ecting the External Auditory Canal

Fig 3.26 The skin covering the exostoses has

been detached and reflected anteriorly and

medially Osteomas are removed with a curette

Fig 3.27 The skin is pushed medially to the

protrusions to make some room for drilling To

save time, most of the bone work is performed

with cutting burrs

Fig 3.28 The canalplasty has reached the area

of the t ympanic membrane Some bone

over-hang remains near the tympanic membrane

The final bony overhang can be removed with a

small diamond burr and a curette Great care

should be taken not to touch the lateral process

of the malleus during drilling the anterosuperior

wall

Diseases A ecting the External Auditory Canal

23

Sum m ary

Surgery in cases of exostosis is indicated only in case withobstructing stenosis with or without hearing loss but with fre-quent otitis externa due to retention of debris Surgery can beperformed under local anesthesia, preferably using a postauricu-lar incision This approach allows excellent exposure of the wholemeatus, thus minimizing the risk of injury to the tympanic mem-brane In addition, it enables the surgeon to preserve the canalskin, thereby avoiding postoperative cicatricial stenosis After dis-secting the posterior limb, the flap is retained by the prongs ofthe self-retaining retractor The skin of the anterior wall is incisedmedial to the tragus and is dissected in a lateral-to-medial direc-tion While drilling the exostosis, the skin of the canal is pro-tected using an aluminum sheet (the cover of surgical sutures).Osteoma can be removed by using a curette In case of recur-rence, wide drilling of the bone around its base is also indicated

Fig 3.29 The meatal skin is replaced over thebony wall Note that the skin is well preserved,and the tympanic membrane remains intact

Fig 3.30 Postoperative otoscopy (6 months) The external auditory

canal has been perfectly calibrated All the t ympanic membrane is

visible

Diseases A ecting the External Auditory Canal

3.2 External Auditory Canal

Inflam m atory Diseases

3.2.1 Eczem a

Eczem a is a derm o-epiderm al process of reactive nature resulting

from local or general factors Local factors include allergy, topical

m edical preparations, or cosm etics, w hereas general factors

include hepatic or gastrointestinal dysfunction It m anifests by

itching, a burning sensation, vesication, and som etim es serous

otorrhea Treatm ent consists of discontinuing the suspected

caus-ative irritant, correction of the system ic disturbances, as w ell as

lavage w ith boric acid w ith alcohol and steroid lotion (see

Fig 3.31, Fig 3.32)

3.2.2 Otitis Ext erna

Otitis externa is an inflam m ation of the skin of the EAC The

inflam m ation can be secondary to derm atitis (eczem a) only, w ith

no m icrobial infection, or it can be caused by active bacterial or

fungal infection In either case, but m ore often w ith infection, the

ear canal skin sw ells and m ay becom e painful or tender to touch

Acute otitis externa is predom inantly a m icrobial infection (i.e.,

Pseudomona s aeruginosa) Wax in the ear can com bine w ith the

sw elling of the canal skin and any associated pus to block the

canal and dam pen hearing to varying degrees, creating a tem

po-rary conductive hearing loss In m ore severe or untreated cases,

the infection can spread to the soft tissues of the face that

surround the adjacent parotid gland and the jaw joint, m akingchew ing painful The t wo factors that are required for externalotitis to develop are: the presence of germ s that can infect theskin and im pairm ents in the integrity of the skin of the ear canalthat allow infection to occur How ever, if there are chronic skinconditions that a ect the ear canal skin, such as atopic derm atitis,seborrheic derm atitis, psoriasis, or abnorm alities of keratin pro-duction, or if there has been a break in the skin from traum a,even the norm al bacteria found in the ear canal m ay cause infec-tion and full-blow n sym ptom s of external otitis At the otoscopicexam ination, the canal appears red and sw ollen Touching or

m oving the outer ear increases the pain, and this m aneuver onphysical exam is im portant in establishing the clinical diagnosis

Therapy consist of cleaning the ear w ith 2% alcohol boric, tion of local antibiotic, oral antibiotic, and analgesic in advancedcases Necrotizing external otitis (m alignant otitis externa) is anuncom m on form of external otitis that occurs m ainly in elderlydiabetics, being som ew hat m ore likely and m ore severe w hen thediabetes is poorly controlled Even less com m only, it can developdue to a severely com prom ised im m une system Beginning asinfection of the external ear canal, there is extension of infectioninto the bony ear canal and the soft tissues deep to the bony canal

instilla-w ith further extension to the skull base Necrotizing external tis requires oral or intravenous antibiotics for cure (fluoroquino-lones plus cephalosporins), even for m ore than 2 w eeks Diabetescontrol is also an essential part of the treatm ent (see Fig 3.33,Fig 3.34, Fig 3.35, Fig 3.36, Fig 3.37)

oti-Fig 3.31 Right ear Chronic eczema of the external auditory canal

Squamous debris covering the skin of the external auditory canal can

be observed Successfully treated by the use of local steroid lotion

Fig 3.32 Chronic eczema of the external auditory canal skin

Exostoses and osteoma are also evident The accumulation of skindebris and wax could lead to external otitis

Diseases A ecting the External Auditory Canal

25

Fig 3.33 Acute otitis externa The external auditory canal appears

swollen with skin debris and some otorrhea The t ym panic

membrane is not visible In case of no response after appropriate

and prolonged therapy, it’s important to exclude malignant disease

that could get into differential diagnosis (i.e., carcinoma of the

external auditory canal)

Fig 3.34 A polyp-like mass is present in the external auditory canal.The patient, who had already undergone t wo t ympanoplasties,

complained of pain in the ear He has suffered from diabetes for

15 years A biopsy performed under local anesthesia excludedneoplastic disease A scintigraphic examination confirmed thediagnosis of malignant external otitis The patient was treated with along course of antibiotic therapy, with final resolution of the

pathology

Fig 3.35 Right ear Malignant otitis externa in a 60-year-old patient

affected by type I diabetes The otoscopy is similar to that in Fig 3.33

The patient had no remission with standard antibiotic therapies and

developed skull base osteomyelitis (confirmed by CTscan, MRI, and

scintigraphy) She further developed facial nerve and lower cranial nerves

paralysis, which recovered after hospitalization and intravenous antibiotic

therapy The patient is still under antibiotic therapy (duration 4 months)

with slight improvement of the clinical condition

Fig 3.36 Gallium67 scintigraphy shows accumulation of the nuclide at the level of the temporal bone, the temporomandibularjoint, and the clivus This technique is useful in diagnosis as well as formonitoring the response to treatment and detecting recurrence

radio-Diseases A ecting the External Auditory Canal

3.2.3 Foruncolosis

Foruncolosis is a pustular folliculitis by staphylococcal infection

of a hair follicle Infection occurs as a result of m icroabrasion or

of decreased im m unity, as in diabetics It is characterized bysevere pain A tender sw elling is seen in the cartilaginous part ofthe EAC, w hich m ay have a central necrotic part (see Fig 3.38)

3.2.4 Otom ycosis

Otom ycosis is m ore com m on in tropical and subtropical tries In the m ajority of cases, the isolated fungi are of the Asper-gillus (niger, fumigatus, flavescens, albus) or the Candida species

coun-Otom ycosis is m ore com m on in im m unocom prom ised patientsand in diabetics Local factors that favor fungal infections includechronic otorrhea and the presence of epithelial debris Clinically,the patient com plains of otorrhea, itching, and hearing loss Ther-apy consists of cleaning the ear to rem ove all debris and theinstillation of local antim ycotic preparations as w ell as lavage

w ith 2% alcohol boric acid drops (see Fig 3.39, Fig 3.40,Fig 3.41, Fig 3.42, Fig 3.43)

Fig 3.37 CTscan Axial view Bone erosion is evident at the level of the

anterior wall of the external auditory canal (white arrow) and the

petrous apex (yellow arrow) The pathology completely involves the

middle ear and the mastoid

Fig 3.38 A furuncle almost totally occluding the meatus Pain is

caused by distention of the richly innervated skin A central necrotic

part is seen Fig 3.39 Right ear Radical mastoid cavit y showing cholesteatomawith superimposed fungal infection.

Diseases A ecting the External Auditory Canal

27

Fig 3.40 An ear with chronic suppurative otitis media with

choles-teatoma showing a superimposed fungal infection The blackish fungal

masses are early recognized They should be removed before local

antifungal solution is instilled

Fig 3.41 Another example of otomycosis in a radical mastoid cavit y

Fig 3.42 Right ear Otomycosis (Candida infection) The patient suffered

from chronic otitis with occupational exposure to humid environments

The external auditory canal is filled with whitish lamellar material Usually,

it is not necessary to perform a culture of ear secretions and the diagnosis

is clinical The lack of response to a topical antibiotic therapy is a further

confirmation of the fungal nature of the infection

Fig 3.43 Same ear after 10 days therapy with ear lavages andantimycotic drops The external auditory canal is almost free fromfungal secretions A simple perforation of the inferior quadrants of the

t ympanic membrane is visible

Diseases A ecting the External Auditory Canal

3.2.5 Myringitis and Meatal Stenosis

Myringitis is an inflam m atory process that a ects the tym panic

m em brane Three form s are recognized: acute m yringitis, bullous

m yringitis, and m yringitis granulom atosa Acute m yringitis is

usually seen in association w ith infection of the external ear

(oti-tis externa) or m iddle ear (oti(oti-tis m edia) It is characterized by

hyperem ia and the presence of purulent secretions Therapy

con-sist of adm inistration of general and/or local antibiotics and local

steroids Bullous m yringitis is com m only associated w ith viral

upper respiratory tract infection It is characterized by the

pres-ence of bullae filled w ith serosanguineous fluid The bullae are

located betw een the outer and the m iddle layers of the t ym panic

m em brane The patient com plains of otalgia and hearing loss

Therapy consist of antibiotics and steroids In granulom atous

m yringitis, the outer epiderm ic layer of the tym panic m em brane

as well as the adjacent skin of the EAC are replaced by tion tissue It is generally seen in patients su ering from frequentepisodes of otitis externa In som e cases, it m ay ultim ately lead tostenosis of the m ost m edial part of the EAC It can usually becured, how ever, by rem oving the granulation in the outpatientclinic using the m icroscope This is followed by the adm inistra-tion of local steroid drops for nearly 1 m onth In refractory cases,how ever, surgery in the form of canalplast y w ith free skin graft isnecessary (see Fig 3.44, Fig 3.45, Fig 3.46, Fig 3.47,Fig 3.48, Fig 3.49, Fig 3.50, Fig 3.51, Fig 3.52,Fig 3.53, Fig 3.54, Fig 3.55, Fig 3.56, Fig 3.57,Fig 3.58, Fig 3.59)

granula-Fig 3.44 Left ear The tympanic membrane is characterized by

thickening and hyperemia In this case, the skin of the external

auditory canal is also hyperemic The t ympanic membrane seems

lateralized

Fig 3.45 Acute myringitis of a left t ympanic membrane The area ofthe malleus handle is hyperemic and the tympanic membrane seemslateralized A small tympanic perforation is visible in the anterior–

inferior quadrant

Diseases A ecting the External Auditory Canal

29

Fig 3.48 Right bullous myringitis The patient complained of a bad flu

few days before the examination Bleeding from the ear is quite

common, due to the rupture of the bullae

Fig 3.49 Granulomatous myringitis The granulomatous tissue hasreplaced the external skin layer of the tympanic membrane and part ofthe anterior wall of the external canal This case was treated by removal ofthe granulation tissue under localanesthesia in the outpatient clinic Localsteroid drops were then administered for 1 month

Fig 3.46 Acute myringitis The tympanic membrane over the malleus

handle is hyperemic A large t ympanosclerosis plaque is visible on the