Atlas of Acoustic Neurinoma Microsurgery: . Zus.-Arb.: Mario Sanna Essam Saleh, Benedict Panizza, Alexandra Russo, Abdel TaibahWith the collaboration of Refik Caylan, Fernando Mancini

321 Pages·2011·49.48 MB·English

by  Mario Sanna

Atlas of Acoustic Neurinoma Microsurgery
Mario Sanna, MD Abdelkader Taibah, MD
Professor ofOtolaryngology GruppoOtologico
DepartmentofHeadandNeckSurgery CasadiCura“Piacenza”
UniversityofChieti PiacenzaandRome,Italy
Chieti,Italy
GruppoOtologico Maurizio Falcioni, MD
PiacenzaandRome,Italy
GruppoOtologico
CasadiCura“Piacenza”
Fernando Mancini, MD
PiacenzaandRome,Italy
GruppoOtologico
CasadiCura“Piacenza” Giuseppe Di Trapani, MD
PiacenzaandRome,Italy
GruppoOtologico
OspedaleKoelleker
CasadiCura“Piacenza”
Turin,Italy
PiacenzaandRome,Italy
Alessandra Russo, MD
GruppoOtologico
CasadiCura“Piacenza”
PiacenzaandRome,Italy
Withthecollaborationof
MasashiHamada,KevinChong,GiuseppeDeDonato,EnricoPiccirillo,AntonioCaruso,LorenzoLauda,
GruppoOtologico,Piacenzaand Rome,Italy;RobertoRizzoli,CasadiCura“Piacenza”,PiazenzaandRome,Italy
2nd edition
1007illustrations
Thieme
Stuttgart·NewYork
IV
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V
Preface
Aspatients’requirementsofthequalityofsurgicalproceduresare only otologists. It is important to note that if two surgeons of
increasing,thetechniquesofsurgeryshouldalwaysbeevolvingin different specialties are involved in a team, both of them must
ordertoprovidebetteroutcomes.Nowhavingperformedalmost knowhowtoperformallthestepsfromsettingtoclosure.Allthe
3500proceduresonposteriorfossalesionsandmorethan2000 surgeons mustknowalltheapproachesthat can be appropriate
onacousticneurinomas,wefeelstronglythatweneedtoupdate for the patient with an acoustic neurinoma. In other words, we
the techniques as well as the results obtained with this kind of mustapplythebestproceduretoourpatients,nottheopposite,as
surgery. requiredbyatrueindividualizedmanagement.
ThesecondeditionofAtlasofAcousticNeurinomaMicrosurgery Webelievethatthisnewbookwillbeofgreathelptoallreaders
comestofruition10yearsafterthefirstedition.Duringthepast inbecoming and beingspecialistsand performingexcellentsur-
decade we have introduced some technical modifications into geryonpatientswithacousticneurinoma.
acoustic neurinoma microsurgery and in this second edition we I would like to acknowledge my gratitude to Dr. Alessandra
haveattemptedtodevotemorepagestotheserefinements. Russo,Dr.AbdelkaderTaibah,Dr.MaurizioFalcioni,andDr.Giu-
Wehaveaddedtwonewchaptersinresponsetorequeststhat seppe Di Trapani, who have associated with me for many years
have been made over that period. Since the role of functional andco-authoredtheelaboratedworkpresentedinthisbook;the
surgery has become established, intraoperative monitoring of many discussions and analyses of our work that we shared to-
thefacialnerveandthecochlearnerveisnowessentialinremoval getherasateamareacrucialpartofthisedition.
of acoustic neurinoma. Great technological advance in implant- I would like to thank Dr. Fernando Mancini for his beautiful
able devices(i.e., cochlear and brainstemimplants)hasallowed illustrations,whichhavecontributedsignificantlytothedidactic
deafpatientstoregainhearing.Inthelightofthesechanges,we power of this book. My thanks extend to Dr. Masashi Hamada
canoffermoretreatmentoptionstopatientswithneurofibroma- from Japan and Dr. Kevin Chong from Singapore, who initially
tosistype2andpatientswithneurinomaintheonlyhearingear, started the project. Thanksalsogoto thosewhohavehelped to
situations that have long bothered both patients and surgeons. prepare this book: Dr. Giuseppe De Donato, Dr. Enrico Piccirillo,
Thesechangeshave,furthermore,introducednewconceptsinthe Dr.AntonioCaruso,andDr.LorenzoLauda,whohavebeenwork-
policyoffollow-up,whichhaschangedfromasimplewait-and- ingwithmeinthisgroupformanyyears.
scanroute. Throughouttherehavebeenmanyothers,allofmyclinicaland
TheinitialmilestoneofskullbasesurgerywaslaidbyWilliam researchcolleagues,whohavemadeinformalcontributions:my
House together with William Hitselberger. They pioneered and thankstothemallfortheirresearchprojectsandtheirpersistent
systematizedthetechniquesneededforremovalofacousticneu- questioning in thepursuitand gaining ofknowledge.Thanksgo
rinomas and made the way for future generations to develop alsototheeditorialstaffofThiemePublishersfortheirexcellent
subsequent advances. Acoustic neurinomas nowadays represent cooperationandcongenialityinhelpinginpreparingthisbook.
a specialist field of pathology. Surgeons treating this pathology Finally, Iwould liketothank and dedicatethisbook to allthe
mustbespecialists,whetherotolaryngologistsorneurosurgeons. families of the people who have kindly agreed to their photo-
Additionally,removalofacousticneurinomaistobeperformedby graphsbeingusedforeducationalpurposes.Theirhelphasmade
ateam,inwhichtwoormoresurgeonsshouldbeinvolved.The ourworkpossible.
ideal may be a team consisting of one otologist and one neuro-
surgeon at minimum, but this is not absolutely necessary – our
workdemonstratedherehasbeenachievedbyateamincluding MarioSanna,MD

VII
Contents
1 GeneralFeaturesofAcousticNeurinomas . . . . . . . . . . . . 1 Drills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Pathogenesis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 BipolarCoagulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Epidemiology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Microinstruments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
NaturalHistory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 PostoperativeManagement. . . . . . . . . . . . . . . . . . . . . . . 38
SignsandSymptoms . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 PostoperativeMedication . . . . . . . . . . . . . . . . . . . . . . . . 38
HearingLoss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Discharge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Tinnitus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Disequilibrium. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
5 SurgeryintheCerebellopontineAngle:GeneralConcepts 40
CerebellarDysfunction. . . . . . . . . . . . . . . . . . . . . . . . . . . 2
SurgicalOrientationintheCerebellopontineAngle . . . . . . 40
TrigeminalNerveInvolvement . . . . . . . . . . . . . . . . . . . . . 2
InternalAuditoryCanal. . . . . . . . . . . . . . . . . . . . . . . . . . 40
FacialNerveInvolvement . . . . . . . . . . . . . . . . . . . . . . . . . 2
CerebellopontineAngle. . . . . . . . . . . . . . . . . . . . . . . . . . 41
LowerCranialNerveandBrainstemFindings . . . . . . . . . . . 2
FacialNerve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
HydrocephalusandHeadaches . . . . . . . . . . . . . . . . . . . . . 3
SurgicalTechniquesintheCerebellopontineAngle . . . . . . 44
GeneralGuidelinesforDrilling. . . . . . . . . . . . . . . . . . . . . 44
2 ImagingStudyofAcousticNeurinomas . . . . . . . . . . . . . 4 ManagementofBleeding. . . . . . . . . . . . . . . . . . . . . . . . . 44
TumorAssessment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 HowtoDealwithBrainTissueandOther
MagneticResonanceImaging . . . . . . . . . . . . . . . . . . . . . . 4 NeurovascularStructures. . . . . . . . . . . . . . . . . . . . . . . . . 45
ComputedTomography . . . . . . . . . . . . . . . . . . . . . . . . . . 15 HowtoObtainBetterAccesstotheTumor . . . . . . . . . . . . 46
DifferentialDiagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 TechniquesofTumorDissectionandRemoval . . . . . . . . . . 47
NeurofibromatosisType2 . . . . . . . . . . . . . . . . . . . . . . . . 15
OtherTumors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6 IntraoperativeMonitoring . . . . . . . . . . . . . . . . . . . . . . 52
ResidualTumors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
FacialNerveMonitoring . . . . . . . . . . . . . . . . . . . . . . . . . 52
TherapeuticFollow-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
PostoperativeScans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Instrumentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
WaitandScan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
PurposesofIntraoperativeFacialNerveMonitoring. . . . . . 54
3 DecisionMakinginAcousticNeurinomaSurgery. . . . . . . 25 LocalizationoftheFacialNerve(Mapping) . . . . . . . . . . . . 54
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 IdentificationoftheFacialNerve . . . . . . . . . . . . . . . . . . . 54
SurgicalversusNonsurgicalTreatment. . . . . . . . . . . . . . . . 25 MinimizationofNeuralTrauma . . . . . . . . . . . . . . . . . . . . 55
SmallNeurinomas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Artifacts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
AcousticNeurinomaintheOnlyHearingEar . . . . . . . . . . . 25 ConfirmationoftheFunctionalIntegrityoftheNerve . . . . 56
AcousticNeurinomainPatientswithPoorGeneral ConcludingConsiderations . . . . . . . . . . . . . . . . . . . . . . . 56
Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 CochlearNerveMonitoring . . . . . . . . . . . . . . . . . . . . . . . 56
Radiosurgery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
ManagementofthePatientwithSerious Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
NeurologicalDisorders . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 ConcludingConsiderations . . . . . . . . . . . . . . . . . . . . . . . 59
ManagementofElderlyPatients . . . . . . . . . . . . . . . . . . . . 26
SelectingtheSurgicalApproach . . . . . . . . . . . . . . . . . . . . 27
7 TheTranslabyrinthineApproaches. . . . . . . . . . . . . . . . . 60
TranslabyrinthineversusHearingPreservationSurgeries . . 27
TheEnlargedTranslabyrinthineApproach . . . . . . . . . . . . . 60
TotalversusSubtotalRemoval . . . . . . . . . . . . . . . . . . . . . 29
Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
4 OperatingRoomSetupandPatientCare. . . . . . . . . . . . . 31 Contraindications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
OperationRoomSetup. . . . . . . . . . . . . . . . . . . . . . . . . . . 31 SurgicalAnatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 SurgicalTechnique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Arrangement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 ClinicalApplication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Instruments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
SuctionIrrigation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
VIII Contents
EnlargedTranslabyrinthineApproachwithTransapical 10 TranscochlearApproaches . . . . . . . . . . . . . . . . . . . . . . 205
Extension. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
TransoticApproach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Limitations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
SurgicalAnatomy(RightEar). . . . . . . . . . . . . . . . . . . . . . 94 Contraindications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
SurgicalTechnique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
SurgicalAnatomy(RightEar) . . . . . . . . . . . . . . . . . . . . . . 206
ClinicalApplication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 SurgicalStepsoftheBlind-Sac(Cul-de-Sac)Closure
PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
(LeftEar). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
SurgicalTechniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
SpecialConsiderationsintheTranslabyrinthineApproach. . 114
ClinicalApplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
AnatomicalVariations. . . . . . . . . . . . . . . . . . . . . . . . . . . 114
PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
ManagementofSurgicalMishaps. . . . . . . . . . . . . . . . . . . 123 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
ManagementofNervesandVesselsaroundtheTumor . . . 124
ModifiedTranscochlearApproach . . . . . . . . . . . . . . . . . . . 232
SpecificCharacteristicsoftheTumor . . . . . . . . . . . . . . . . 136 Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Contraindications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
SurgicalAnatomy(RightEar) . . . . . . . . . . . . . . . . . . . . . . 232
8 CombinedRetrosigmoid–RetrolabyrinthineApproach. . . 142
SurgicalTechnique. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
ClinicalApplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
Contraindications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
SurgicalAnatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
SurgicalDissectionDemonstratingtheCombined
Retrosigmoid–RetrolabyrinthineApproach(LeftEar) . . . . . 143 11 ManagementinSpecialSituations . . . . . . . . . . . . . . . . 244
SurgicalTechniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
CurrentStrategyforNeurofibromatosisType2:
AccesstotheTumor(RightEar). . . . . . . . . . . . . . . . . . . . 148 TotalRemovalwithaConcomitantCochlearorBrainstem
TumorRemoval(LeftEar) . . . . . . . . . . . . . . . . . . . . . . . . 150
Implant. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
ClinicalApplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
NeurofibromatosisType2 . . . . . . . . . . . . . . . . . . . . . . . . 244
PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
ClinicalDiagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
ClinicalManifestationsofDisease . . . . . . . . . . . . . . . . . . . 245
Advantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Disadvantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
DecisionMaking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Limitations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 BrainstemImplantationinNeurofibromatosisType2 . . . . . 248
ClinicalApplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
ManagementofAcousticNeurinomainthe
9 EnlargedMiddleCranialFossaApproach . . . . . . . . . . . . 176
OnlyHearingEar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
ClinicalApplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264
Contraindications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
SummaryofAuditoryBrainstemImplants . . . . . . . . . . . . . 266
SurgicalAnatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
TechniqueforIdentificationoftheInternalAuditoryCanal . 178
House’sMethod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Fisch’sMethod(MeatalPlaneApproach). . . . . . . . . . . . . . 178 12 FacialNerveReanimation . . . . . . . . . . . . . . . . . . . . . . 268
Garcia-Ibanez’sMethod. . . . . . . . . . . . . . . . . . . . . . . . . . 179
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
OurMethod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
SurgicalDissectionDemonstratingtheMiddleCranial
End-to-EndAnastomosis . . . . . . . . . . . . . . . . . . . . . . . . . . 268
FossaApproach(LeftEar) . . . . . . . . . . . . . . . . . . . . . . . . 180 KeystoSuccessfulResults . . . . . . . . . . . . . . . . . . . . . . . . 268
SurgicalTechniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
InterpositionGraft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
SpecialPositioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
ClinicalApplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
SurgicalStepsuptotheInternalAuditoryCanal(RightEar). 184
HarvestingtheSuralNerveGraft. . . . . . . . . . . . . . . . . . . . 282
ExposureoftheInternalAuditoryCanal(RightEar). . . . . . 187
HypoglossofacialNerveAnastomosis. . . . . . . . . . . . . . . . . 283
TumorRemoval(RightEar) . . . . . . . . . . . . . . . . . . . . . . . 189 AnatomyoftheHypoglossalNerve . . . . . . . . . . . . . . . . . . 283
Closure(RightEar) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
SurgicalApproach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
ClinicalApplication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
PearlsandPitfalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Advantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Disadvantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Limitations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Contents IX
13 TheRoleofEndoscopyinAcousticNeurinomaSurgery . 286 CerebrospinalFluidLeakage . . . . . . . . . . . . . . . . . . . . . . 298
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 Meningitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 BrainEdema. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
Sterilization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 CranialNerveDefects . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
EndoscopicSurgicalAnatomy . . . . . . . . . . . . . . . . . . . . . . 286 Ataxia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
FromthePosteriorAspectoftheTemporalBone: Hydrocephalus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
RetrosigmoidApproach . . . . . . . . . . . . . . . . . . . . . . . . . . 286 AirEmbolism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
ThroughtheSuperiorSurfaceoftheTemporalBone: Pneumocephalus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
MiddleFossaApproach . . . . . . . . . . . . . . . . . . . . . . . . . . 288 Headaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
TheTechniqueofEndoscopy . . . . . . . . . . . . . . . . . . . . . . . 289 PostoperativeUnsteadiness . . . . . . . . . . . . . . . . . . . . . . . 300
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289 Tinnitus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
TranslabyrinthineApproach . . . . . . . . . . . . . . . . . . . . . . . 289 NonspecificComplications . . . . . . . . . . . . . . . . . . . . . . . . 300
RetrosigmoidApproach . . . . . . . . . . . . . . . . . . . . . . . . . . 293 AtelectasisandPneumonia . . . . . . . . . . . . . . . . . . . . . . . 300
EnlargedMiddleFossaApproach. . . . . . . . . . . . . . . . . . . . 293 DeepVenousThrombosisandPulmonaryEmbolism . . . . . 301
RisksofCerebellopontineAngleEndoscopy . . . . . . . . . . . . 294 WoundInfectionandHematoma . . . . . . . . . . . . . . . . . . . 301
Transfusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
14 ComplicationsandManagement . . . . . . . . . . . . . . . . . 295
Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
PostoperativeComplicationsSpecifictoCerebellopontine
AngleSurgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
Hemorrhage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
Infarction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296