The rhomboid lip (RL) is a neuroepithelial structure extending from the lateral recess of the fourth ventricle into the cerebellopontine angle (CPA). Although cilia have been described on its surface, their ultrastructural characteristics in adults remain unclear. We characterized the histological and ultrastructural architecture of the adult RL and evaluated its anatomical relevance in CPA surgery.
✦ The floor
Discussion
Signed responses from readers of the wire.
No actionable change for routine audiology practice; this anatomical study is primarily relevant to neurosurgeons and CI surgeons seeking detailed skull-base anatomical reference data.
Precise knowledge of cerebellopontine angle anatomy is critical for the safety of cochlear implant and skull-base surgeries, and detailed ultrastructural mapping of adjacent structures like the rhomboid lip may reduce surgical risk.
- 01Describes the 9+2 ciliary ultrastructure of the adult human rhomboid lip for the first time in this context.
- 02Published in World Neurosurgery, focusing on surgical anatomy of the cerebellopontine angle.
- 03The cerebellopontine angle is a key region in cochlear implant and skull-base surgery.
- 04Anatomical insights may help surgeons plan safer approaches and avoid neural structures.
- 05Primarily a descriptive anatomical study with limited immediate clinical trial evidence.
The adult human rhomboid lip exhibits a 9+2 ciliary ultrastructure.
studysupported- PMID
- 42759651
- DOI
- 10.1016/j.wneu.2026.125339.
- Journal
- World Neurosurgery
- Publication type
- research_article
- Evidence level
- 4
- Population
- Adult human cadaveric or surgical specimens of the rhomboid lip/cerebellopontine angle
- Intervention
- Anatomical and ultrastructural characterisation of the rhomboid lip
Primary outcomes
Ciliary ultrastructure of the rhomboid lip; Surgical anatomy of the cerebellopontine angle