Rotational Stability of Single-Piece Hydrophobic Acrylic Intraocular Lens During Removal of OVD

1
Rotational Stability of Single-Piece
Hydrophobic Acrylic Intraocular Lens During
Removal of OVD

• Hwan Eok Yeo, MD1,4
• Won Ryang Wee, MD2,3
• Jin Hak Lee, MD1,3
• Joon Young Hyon, MD1,3

1. Department of Ophthalmology, Seoul National
University Bundang Hospital, Seongnam, Korea 2.
Department of Ophthalmology, Seoul National
University Hospital, Seoul, Korea 3. Seoul
National University College of Medicine, Seoul,
Korea 4. Kims Eye Hospital, Seoul, Korea
The authors have no financial interest
2
Purpose

• The toric IOL with a single-piece hydrophobic
  acrylic platform showed satisfactory
  postoperative torsional stability. However,
  unintended intraoperative rotation of the IOL may
  occur during removal of the OVD
• To evaluate the rotational stability of a
  foldable hydrophobic single-piece acrylic IOL
  during removal of OVD and assess the suitability
  of IOL platform as a toric lOL

3
Patients and Methods

• 20 eyes of 20 patients
• Prospective study
• The position of the IOL was determined from
  digital photograph during surgery
• Before and After removal of OVD
• Unintended over-rotation of the IOL was measured
  with image analysis

4
Patients and Methods

• Surgical Technique
• 2.75 mm temporal clear corneal incision
• Phacoemulsification
• OVD
• Cohesive Healon GV
• Dispersive Viscoat

5
Image analysis
6
Results

• The mean IOL rotation
• 17.1 11.1 degree
• Range from 0.9 up to 42.7
• Rotation within 5 degree 15
• Rotation of 5 degree to 15 degree 25
• Rotation over 15 degree 60
• The mean IOL rotation of two OVDs
• Cohesive OVD 22.59.3 degree
• Dispersive OVD 11.610.28 degree

7
IOL Rotation During Removal of OVD
Clockwise rotation
Counter-clockwise rotation
8
Discussion

• Toric IOL implantation is a predictable and
  precise method to control the preexisting corneal
  astigmatism during cataract surgery
• In the present study, 85 of IOLs were out of 5
  degree of intended axis
• The numbers of clockwise rotation were more than
  those of counterclockwise rotation
• Better torsional stability with dispersive OVD

9
Discussion

• The differences in the rotational angle during
  removal of OVD may be explained by several
  factors
• IOL design
• Capsular bag size
• Character of OVD
• Surgical techniques
• starting of removal before fully unfolding of
  IOL, aggressive irrigation and aspiration,
  anterior chamber collapse after drawing of the
  IA device

10
Conclusion

• IOL rotation could occur during removal of OVD,
  amount of which may be visually significant
• Verification of the IOL axis after removal of OVD
  should be warranted to achieve the intended
  amount of astigmatic correction with the toric
  IOL of a single-piece hydrophobic acrylic platform

11
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