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Updated: Apr 30, 2026

Transcanalicular Diode Laser-assisted Dacryocystorhinostomy for the Treatment of Primary Acquired Nasolacrimal Duct Obstruction
Published on: October 13, 2017
Lacrimal sac movement under intrasac pressure changes observed with dacryoendoscopy
Yasuhiro Takahashi1, Toru Suzuki, Hirohiko Kakizaki
1*Department of Ophthalmology, Aichi Medical University, Nagakute, Aichi, Japan; and †Suzuki Eye Clinic, Wakamatsu, Kitakyushu, Fukuoka, Japan.
Purpose:
To examine movement of the intrasac cavity under intrasac pressure changes with dacryoendoscopy.
Methods:
The authors examined 10 lacrimal sacs (3 right and 7 left) without lacrimal tract obstruction in 10 Japanese patients (3 men and 7 women) aged 35 to 86 years (average, 62.8 years). These were the contralateral sides of the sides with nasolacrimal duct obstruction that were treated with dacryocystorhinostomy. After enlarging a superior lacrimal punctum, a dacryoendoscope (FT-203F; FiberTech) was inserted. When the tip of the dacryoendoscope passed through the common internal ostium, the handgrip was rotated 90° superiorly to face the tip inferiorly. Water was poured into the cavity throughout this process via the water channel of the dacryoendoscope. Then, with the water poured or suctioned from the same channel, namely causing positive or negative pressure changes in the intrasac cavity, movement of the lacrimal sac wall was examined with dacryoendoscopy.
Results:
The lateral wall of the lacrimal sac moved with pressure changes fairly flexibly. Under positive pressure, the wall moved outward, but it moved inward under negative pressure.
Conclusions:
The present study demonstrated movement of the lacrimal sac wall with intrasac pressure changes, which was suggestive of its contribution to lacrimal drainage of the sac.
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