Repeated rotation of a toric implantable collamer lens A case report

Introduction: Implantable collamer lens have been used widely worldwide, and have been accepted by more and more doctors and patients due to good safety, stability, and effectiveness. However, there is still a problem of crystal rotation. The large angle rotation (over 10 degrees) would weaken the original astigmatism correction effect and even induce irregular astigmatism, seriously affecting the visual quality of patients. Herein, we reported a case who had 2 times of crystal rotations after toric implantable collamer lens (TICL) implantation. Patient concerns: The patient was a 38-year-old man who underwent TICL implantation for the correction of high myopic astigmatism in eyes. He presented a sudden decrease in the visual acuity (VA) of the left eye 4 months after the TICL implantation. The uncorrected visual acuity (UCVA) was 8/20 (refraction, +2.25 -5.25 x 68). Diagnosis: Rotation of TICL was diagnosed. The toric marks with a rotation of 75 degrees counter-clockwise from the original position were observed. Interventions: The TICL was re-set to the original position, leading to the UCVA of 12/20 in the left eye (refraction, -0.00 -0.75 x 131), with the vaulting of 589 mu m. Ten months after the TICL relocation, the patient again presented a sudden decrease in the VA of the left eye, with the UCVA of 2/20 (refraction, +2.25 -5.00 x 66). Again, the toric marks with a rotation of 75 degrees counter-clockwise from the original position was observed, just at the same position as the last rotation. This time, the TICL was removed. The axis and power were recalculated, and a new TICL was implanted, with the rotation of 73 degrees counter-clockwise from the horizontal line of the temporal side. Outcomes: The patient obtained a final UCVA of 12/20 in the left eye (refraction, +0.50 -0.50 x 26), which remained stable in the 6-month follow-up period, with the vaulting of 602 mu m. Lessons: Rotation is a common complication after TICL surgery. Relocation or replacement of TICL are safe and efficient ways to recover VA due to TICL rotation.