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Updated: May 22, 2026
07:30
Transcanalicular Diode Laser-assisted Dacryocystorhinostomy for the Treatment of Primary Acquired Nasolacrimal Duct Obstruction
Published on: October 13, 2017
Lacrimal sac septum
Yasuhiro Takahashi1, Takashi Nakano, Ken Asamoto
1Department of Ophthalmology, Aichi Medical University, Nagakute, Aichi, Japan.
Orbit (Amsterdam, Netherlands)
|May 24, 2012
Summary
The lacrimal sac septum, a newly identified structure, divides the lacrimal sac lumen into two distinct spaces. This anatomical finding offers new insights into orbital anatomy and lacrimal drainage.
Area of Science:
- Ophthalmology
- Anatomy
- Histology
Background:
- The lacrimal sac is a crucial component of the eye's tear drainage system.
- Previous anatomical descriptions have not detailed the internal structure of the lacrimal sac lumen.
Observation:
- Microscopic examination of a human cadaveric right orbit revealed a previously undescribed structure.
- This structure, identified as the lacrimal sac septum, was observed to divide the lacrimal sac's lumen.
Findings:
- The lacrimal sac septum is composed of fibrous tissue with a cavernous structure.
- The septum is lined with stratified columnar epithelium, consistent with the lacrimal sac wall lining.
- This division creates two distinct spaces within the lacrimal sac lumen.
Implications:
- This finding necessitates a revision of the anatomical understanding of the lacrimal drainage system.
- The presence of the septum may influence the dynamics of tear flow and lacrimal sac function.
- Further research is warranted to explore the clinical relevance of this anatomical variation in conditions affecting the lacrimal sac.
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