Dose-Effect Relationship of Unilateral Medial Rectus Resection for Recurrent Exotropia

PURPOSE: To investigate the dose-effect relationship of unilateral medial rectus resection for recurrent exotropia after bilateral lateral rectus recession. METHODS: This study comprised 39 patients who underwent unilateral medial rectus resection for recurrent exotropia under 25 PD and bilateral rectus recession for prior surgery of exotropia. The medial rectus was resected from 5.0 to 7.0 mm according to angle deviation at a distance. The postoperative deviated angle was checked at one week, 3 months and 6 months postoperatively to investigate the amount of corrected deviation per resected muscle. RESULTS: The average preoperative deviation was 21.33 +/- 2.96 PD. We resected mean 6.26 +/- 0.57 mm of the medial rectus muscle. The postoperative deviated angle was 0.82 +/- 3.47, 1.87 +/- 3.10 and 5.40 +/- 4.79 PD at 1 week, 3 months and 6 months after surgery, respectively. The corrected deviated angle per millimeter (mm) was 3.29 +/- 0.68, 3.17 +/- 0.58 and 2.75 +/- 0.89 PD at 1 week, 3 months and 6 months after surgery. There were no significant differences among the changes of postoperative deviation per millimeter according to the amount of medial rectus (MR) resection (p-value = 0.423, 0.382) The success rate was 89.75%, 92.31% and 87.18% at 1 week, 3 months and 6 months after surgery, respectively. The expected corrected angle according to the amount of resection remained constant and was 3.04-3.22 PD/mm at 3 months after surgery and 2.79-2.82 PD/mm at 6 months after surgery. CONCLUSIONS: The dose-effect per millimeter was decreased as time passed. There was no statistical difference among the corrected deviation angles per millimeter according to the amount of MR resection. We expect that the calculated dose-effect relationship may be a useful guideline for unilateral medial rectus resection for recurrent exotropia.

Clinical Outcomes of M-Plus Intraocular Lenses

PURPOSE: To evaluate the clinical outcomes of eyes implanted with a zonal refractive multifocal intraocular lens (IOL) with an inferior segmental near add (M-plus), and to compare the outcomes between M-plus and a diffractive-type multifocal IOL, AT LISA (366D, bifocal). METHODS: We reviewed 19 eyes from 10 patients who were implanted with M-plus and 52 eyes of 26 patients who were implanted with AT LISA. The clinical outcomes of these 2 intraocular lenses were evaluated at 1 day and 2 months postoperatively, and consisted of distant, intermediate, and near visual acuity, contrast sensitivity, degree of tilt, and decentration using anterior segment photography, depth of focus, and patient satisfaction. RESULTS: There were no statistical differences between the 2 groups with respect to distant vision, near vision, refractive error, contrast sensitivity, degree of tilt, decentration, or satisfaction score. The M-plus group demonstrated significantly better intermediate visual acuity. In the defocus curve, the M-plus group also demonstrated significantly better visual acuities for intermediate unfocused vision levels. CONCLUSIONS: The M-plus multifocal IOLs are able to provide satisfactory distant and near visual acuity and visual function. The M-plus multifocal IOLs provide better intermediate vision than the AT LISA.

Target Refraction and Satisfaction of Patients with Binocular Myopia and Monocular Cataract

PURPOSE: To evaluate the target refraction of patients with binocular myopia and monocular cataract after intraocular lens (IOL) implantation. METHODS: This study comprised 199 patients with binocular myopia (axial length >25 mm) and monocular cataract after IOL implantation for the removal of the monocular cataract. The research was conducted using a questionnaire method and by performing statistical analysis of the refractive outcomes. RESULTS: The patients are grouped into 3 domains (-6 D group). There were no statistically significant differences among the 3 groups; whereas the satisfaction of the present corrected state was statistically low in the >-6 D group (p < 0.05). The satisfaction of the corrected state was statistically high in the group of postoperative anisometropia under 3 D (p < 0.05). There was no statistical difference between the groups on the satisfaction of target diopter (-2~-3 D or emmetropia). In terms of correction method, glasses were worn in 119 patients (60%), contact lenses were worn in 26 patients (13%), and monovision was used in 14 patients (7%) were used respectively. Forty patients (20%) with implanted IOL in both eyes did not use any of the correction methods above. Except for the contact lens group, the general satisfaction and the satisfaction of the present corrected state were statistically lower than the other group (p < 0.05). There was no statistically significant difference among the 3 groups in the percentage of cataract surgery in the fellow eye. CONCLUSIONS: There was no statistical difference between the groups in satisfaction of target diopter (-2~-3 D or emmetropia). Setting the target refraction difference between both eyes less than 3 D leads to more satisfactory outcomes.