Ocular structure changes during vacuum by the Hansatome microkeratome suction ring.

Area of Science:

• Ophthalmology
• Ophthalmic Surgery
• Ocular Biomechanics

Background:

• Laser-Assisted In Situ Keratomileusis (LASIK) is a common refractive surgery.
• Microkeratome use involves a suction ring to stabilize the eye.
• Understanding intraocular pressure dynamics during LASIK is crucial for patient safety and outcomes.

Purpose of the Study:

• To investigate the immediate effects of microkeratome suction ring vacuum on ocular structures.
• To quantify changes in anterior chamber depth, lens thickness, vitreous body, and axial length.

Main Methods:

• Prospective case series involving 69 eyes of 39 patients undergoing primary LASIK.
• A-scan ultrasonography was used to measure key ocular parameters.
• Measurements were taken before and during the application of the Hansatome microkeratome suction ring.

Main Results:

• A statistically significant decrease in anterior chamber depth (-0.06 mm) and lens thickness (-0.14 mm) was observed.
• A significant increase in vitreous body volume (0.25 mm) was noted.
• No significant changes in axial length were detected during vacuum application.

Conclusions:

• Microkeratome suction ring vacuum induces transient compression of the anterior segment and expansion of the vitreous.
• Intraocular compartment measurements provide more insight into vacuum effects than axial length alone.
• These findings are relevant for understanding ocular biomechanics during LASIK.