Superior Semicircular Canal
Dehiscence Update
Alejandro Rivas MD
Assistant Professor
Division of Otology-Neurotology and Skull Base Surgery
Dept. of Otolaryngology- Vanderbilt University
Conflict of Interest
• Alejandro Rivas
– None
HA
• 48 yo F ice skater trainer:
– Multiple head concussion
– Conductive hearing loss
– “I can hear my own voice”, “I can hear my eyes
move”
– Dizziness
• Dx: Non specific post-concussion Dizziness
for 3 years
CC
• 20 M, college football player,
– h/o of head traumas
– Oscillopsia and disequilibrium during
physical activities.
– “Eyes jump while weight lifting ”
AS
72 yo M s/p MVA and head concussion
• Oscillopsia
• Disequilibrium
• Dizziness- “eyes
jump” on
– Valsalva
– Loud Noises
– Hyperventilation
• Conductive
Hearing loss
• Autophony
• Ear Fullness
• Pulsatile Tinnitus
Labyrinth
Physiopathology
Crane, Gasscock, 2010
White, Otol Neurotol, 2007
Tullio Phenomenon
Histopathologic Findings
1.4%
0.7%
Carey, Arch Oto-HNS, 2000
Etiology
• Congenital / Development Defect
– Trauma
– Microfractures
– Meningeal Pulsations
Carey, Arch Oto-HNS, 2000
Clinical Diagnosis
• History and physical exam
•Audiometry
– Mixed or conductive hearing loss
– Present stapedial reflex, present OAE
•VEMPs: Screening
•ECoG
CT confirms the diagnosis
•CT based diagnosis alone
– High false positive
– 4% present SSCD on CT
– 0.6-.07% present SSCD on temporal bone
cadaveric studies
Carey, Arch Oto-HNS, 2000
CT
•Special cuts
Stenver’s:
Ortogonal
CT
Stenver’s:
Ortogonal
CT
Stenver’s:
Orthogonal
CT
Stenver’s:
Orthogonal
CT
Stenver’s:
Orthogonal
CT
•Posch’s: Parallel
CT
•Posch’s: Parallel
CT
•Posch’s: Parallel
CT
•Posch’s: Parallel
CT
•Posch’s: Parallel
CT
•Posch’s: Parallel
CT
•Posch’s: Parallel
Treatment
•Observation
•SSC Resurfacing
– Middle Fossa Approach
•SSC Plugging
– Middle Fossa Approach
– Transmastoid Approach
SSCD Middle Fossa Plugging
Crane, Gasscock, 2010
SSCD Middle Fossa Plugging
Crane, Gasscock, 2010
SSCD Middle Fossa Plugging
Crane, Gasscock, 2010
SSCD Middle Fossa Plugging
Crane, Gasscock, 2010
SSCD Middle Fossa Plugging
Results
•
•
•
•
95% improvement of symptoms
10% decrease funcion in PSC.
3% Unilateral vestibular weakness
3% Decrease hearing.
Thank You