Superior Canal Dehiscence Involving the Superior Petrosal Sinus: A Novel Classification Scheme

Otol Neurotol. 2018 Oct;39(9):e849-e855. doi: 10.1097/MAO.0000000000001965.


Objectives: To highlight superior semicircular canal dehiscence (SSCD) involving the superior petrosal sinus (SPS), and to propose a novel classification system for SPS associated SSCD with potential surgical implications.

Study design: Multicenter retrospective review.

Setting: Three tertiary referral centers.

Patients: All patients diagnosed with SPS associated SSCD (1/2000 to 8/2016). Radiographic findings and clinical symptoms were analyzed.

Intervention: Surgical repair or observation.

Main outcome measure: Radiographic findings and clinical symptoms were analyzed.

Results: Thirty-three dehiscences (30 patients) involving the SPS were identified. The average age at the time of presentation was 52.5 years (median, 56.9; range, 4.9-75.3 yr), and 53.3% of patients were men. Three patients had bilateral SPS associated SSCD. The most common associated symptoms at presentation were episodic vertigo (63.6%), subjective hearing loss (60.6%), and aural fullness (57.6%). Four distinct types of dehiscence were identified: class Ia. SSCD involving a single dehiscence into an otherwise normal appearing SPS; class Ib. SSCD involving a single dehiscence into an apparent venous anomaly of the SPS; class IIa. SSCD involving two distinct dehiscences into the middle cranial fossa and the SPS; class IIb. SSCD involving a single confluent dehiscence into the middle cranial fossa and the SPS.

Conclusions: SSCD involving the SPS represents a small but distinct subset of SSCD cases. This scenario can create a unique set of symptoms and surgical challenges when intervention is sought. Clinical findings and considerations for surgical intervention are provided to facilitate effective diagnosis and management.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Child
  • Child, Preschool
  • Cranial Sinuses / diagnostic imaging*
  • Cranial Sinuses / surgery
  • Female
  • Hearing Loss / classification*
  • Hearing Loss / diagnostic imaging
  • Hearing Loss / surgery
  • Humans
  • Labyrinth Diseases / classification*
  • Labyrinth Diseases / diagnostic imaging
  • Labyrinth Diseases / surgery
  • Male
  • Middle Aged
  • Retrospective Studies
  • Semicircular Canals / diagnostic imaging*
  • Semicircular Canals / surgery
  • Young Adult