Efficacy of haptic sutured in-the-bag intraocular lens for intraocular lens-capsule complex stability: a comparison of three insertion methods

Abstract

Aim: To evaluate the efficacy and stability of haptic sutured in-the-bag intraocular lens (IOL) in eyes with zonular instability.

Methods: A total 60 eyes of 60 patients were included in this retrospective cohort study. Postoperative stability in three groups [haptic sutured IOL in the bag, IOL in the bag insertion with haptics oriented toward areas of zonulysis, IOL with capsular tension ring (CTR) in the bag insertion] were compared according to the IOL insertion methods. To evaluate the IOL stability, the changes of anterior chamber depth (ACD), refraction, contraction of anterior continuous curvilinear capsulotomy (CCC) area, and tilt of IOL were compared.

Results: There was no significant difference in change of ACD (-0.04±0.01 mm in group of haptic sutured IOL, -0.07±0.01 mm in group of CTR insertion) and refraction (0.05±0.05 D in group of haptic sutured IOL, 0.37±015 D in group of CTR insertion) between the group of haptic sutured IOL in the bag and CTR insertion group. But in comparison of CCC contraction and IOL tilt, CTR insertion group showed less contraction (1.00%±0.52%) and less IOL tilt (2.66°±0.11°) than the group of haptic sutured IOL in the bag (6.32%±1.36%, 3.47°±0.11°, respectively). The CTR insertion group showed the least CCC contraction and the least tilt.

Conclusion: In eyes with zonular instability, the method of haptic sutured IOL in-the-bag shows comparable stability in ACD and refraction in comparison with IOL with CTR in the bag insertion. The method of IOL only in-the-bag insertion shows the largest contraction of CCC and the largest tilt of IOL.

Keywords: capsular tension ring; haptic sutured in the bag; zonular instability.

Figure 1. Three techniques for IOL insertion

A: Group 1 (IOL in the bag): a three-piece IOL inserted in the bag with the haptic oriented toward the area of zonulysis; B: Group 2 (IOL with CTR in the bag): a three-piece IOL inserted after injection of a 12 mm standard CTR; C: Group 3 (haptic sutured IOL in the bag): three-piece IOL with haptic scleral suture fixated inserted in the bag. Each end of the polypropylene suture was tied near the three-piece IOL optic-haptic junction. The opposite end of the polypropylene suture was placed through a trans-scleral tunnel, tied, and adjusted. CTR: Capsular tension ring; IOL: Intraocular lens.

Figure 2. Measurement of IOL tilt

A: Original Scheimpflug image at 1-year postoperatively; B: IOL tilt measure by Image J software on edited image (autodesk sketchbook^®). The line between the anterior chamber angle (red line in B) and the line between the IOL edges (yellow line in B) were marked. The IOL tilt angle between red line and yellow line was measured using the reference line of Scheimpflug image (dotted line in A and B). IOL: Intraocular lens.

Figure 3. Two aspects of continuous curvilinear capsulotomy contraction, shape and area, were measured

A: Original postoperative picture of continuous curvilinear capsulotomy area; B: The difference between the length of longest line and shortest line of two opposite axis in edited image with overlying ellipse (autodesk sketchbook^®) of postoperative picture.

Figure 4. The CCC area was measured using Image J software

A, B: Group 1 (IOL in the bag) examples. The outermost yellow line in A marks the corneal limbus, and the area enclosed was measured with Image J software and used as the reference area. The yellow line in B marks the CCC margin and encloses the CCC area measured by image J. C, D: Postoperative picture of CCC area in Group 2 (IOL with CTR in the bag). E, F: Postoperative picture of CCC area in Group 3 (haptic sutured IOL in the bag). In each eye, the CCC area inside of capsulotomy margin was calculated as a percentage area of the total corneal area. The percentage area difference between postoperative 1 and 12mo was then calculated and recorded as CCC contracture. CCC: Continuous curvilinear capsulotomy; CTR: Capsular tension ring.

Figure 5. Comparison of IOL tilt (A), axis balance of anterior capsulotomy area (B), and the percentage area of anterior capsulotomy compared with total corneal area (C) in three groups at 1mo postoperatively

CTR: Capsular tension ring; IOL: Intraocular lens.

Figure 6. Comparison of changes in refractive change (A), anterior chamber depth (B), intraocular lens tilt (C), axis balance of the anterior capsulotomy shape (D), contraction of anterior capsulotomy area (E) in three groups between 1mo and 1y postoperatively

CTR: Capsular tension ring; IOL: Intraocular lens. ^aP<0.05, ^bP<0.01.