PURPOSE: To investigate the long-term clinical course of intermittent exotropia after surgical treatment to determine whether and when postoperative exo-drift stabilizes, and the required postsurgery follow-up duration in cases of intermittent exotropia. METHODS: We retrospectively reviewed the medical records of patients diagnosed with intermittent exotropia who underwent surgical treatment between January 1992 and January 2006 at Yeungnam University Hospital and postoperatively performed regular follow-up examinations for up to 7 years. We also analyzed the difference in exo-drift stabilization, according to surgical procedure. RESULTS: A total of 101 patients were enrolled in the study. Thirty-one patients underwent lateral rectus recession and medial rectus resection (R&R) and 70 patients underwent bilateral lateral rectus recession (BLR). The postoperative angles of deviation increased significantly during the initial 36 months, but no subsequent significant changes were observed for up to 84 months. Follow-ups for 7 years revealed that more than 50% of the total amount of exo-drift was observed within the first postoperative year. In addition, the angles of deviation at 1 year correlated with those at 7 years postoperatively (Pearson correlation coefficient r = 0.517, p < 0.001). No significant exo-drift was observed after 36 months in patients who underwent BLR, whereas after 18 months in patients who underwent R&R. CONCLUSIONS: The minimum postoperative follow-up required after surgical treatment to ensure stable results is 36 months. In particular, careful follow-up is necessary during the first postoperative year to detect rapid exo-drift. Patients who underwent BLR required a longer follow-up than those who underwent R&R to ensure stable postoperative alignment.
Child ; Child, Preschool ; Exotropia/*physiopathology/surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Oculomotor Muscles/*physiopathology/surgery ; *Ophthalmologic Surgical Procedures ; Postoperative Complications/*physiopathology ; Retrospective Studies ; Vision, Binocular/physiology ; Visual Acuity/physiology

PURPOSE: To compare postoperative exodrift of the first unilateral lateral rectus (ULR) muscle recession with the exodrift of the second contralateral ULR muscle recession in patients with recurrent small-angle exotropia (XT). METHODS: We evaluated the results of a second ULR muscle recession in 19 patients with recurrent XT with deviation angles under 25 prism diopter (PD), following a first procedure of ULR muscle recession for small-angle XT. Recession of the lateral rectus muscle ranged from 8 to 9 mm. The postoperative motor alignment and degree of exodrift were investigated after the first ULR muscle recession and the second ULR muscle recession in the same patients. RESULTS: Observed differences in postoperative ocular alignment between the first ULR muscle recession and the second ULR muscle recession were statistically significant at follow-up periods of six months (7.84 +/- 4.43 vs. 3.89 +/- 3.47 PD), one year (9.58 +/- 4.97 vs. 5.21 +/- 4.94 PD), and at a final follow-up (21.11 +/- 2.98 vs. 7.52 +/- 4.06 PD) after surgery (p = 0.006, 0.013, and 0.000). Postoperative exodrift was statistically different between the first and second ULR muscle recessions at three to six months (2.89 +/-3.75 vs. 0.63 +/- 3.45 PD) and one year to final follow-up (11.52 +/- 5.50 vs. 2.32 +/- 3.53 PD) (p = 0.034 and 0.000). All of the first ULR muscle recession patients showed XT with deviation angles of more than 15 PD at the final follow-up. Regardless, the surgical success rate (<8 PD) after the second ULR recession was 63.16% (12 patients) among the total amount of patients with recurrent XT. CONCLUSIONS: This study shows that changes in exodrift after a second ULR muscle recession are less than changes after the first URL muscle recession among patients with recurrent XT. A second ULR muscle recession may be a useful surgery for small-angle XT patients with deviation angles of 25 PD or less after a first ULR muscle recession.
Child ; Child, Preschool ; *Exotropia/etiology/physiopathology/surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Oculomotor Muscles/physiopathology/*surgery ; *Ophthalmologic Surgical Procedures ; *Postoperative Complications ; Recurrence ; Retrospective Studies ; Vision, Binocular/physiology

PURPOSE: The purpose of this study is to compare the magnitude and axis of astigmatism induced by a combined inferior oblique (IO) anterior transposition procedure with lateral rectus (LR) recession versus LR recession alone. METHODS: Forty-six patients were retrospectively analyzed. The subjects were divided into two groups: those having concurrent inferior oblique muscle overaction (IOOA) and intermittent exotropia (group 1, 20 patients) and those having only intermittent exotropia as a control (group 2, 26 patients). Group 1 underwent combined anterior transposition of IO with LR recession and group 2 underwent LR recession alone. Induced astigmatism was defined as the difference between preoperative and postoperative astigmatism using double-angle vector analysis. Cylinder power, axis of induced astigmatism, and spherical equivalent were analyzed at 1 week, 1 month, and 3 months after surgery. RESULTS: Larger changes in the axis of induced astigmatism were observed in group 1, with 4.5° incyclotorsion, than in group 2 at 1 week after surgery (axis, 84.5° vs. 91°; p < 0.001). However, there was no statistically significant inter-group difference thereafter. Relaxation and rapid regression in the incyclotorsion of induced astigmatism were observed over-time. Spherical equivalent significantly decreased postoperatively at 1 month in both groups, indicating a myopic shift (p = 0.011 for group 1 and p = 0.019 for group 2) but did not show significant differences at 3 months after surgery (p = 0.107 for group 1 and p = 0.760 for group 2). CONCLUSIONS: Combined IO anterior transposition procedures caused an increased change in the axis of induced astigmatism, including temporary incyclotorsion, during the first week after surgery. However, this significant difference was not maintained thereafter. Thus, combined IO surgery with LR recession does not seem to produce a sustained astigmatic change, which can be a potential risk factor of postoperative amblyopia or diplopia compared with LR recession alone.
Astigmatism/diagnosis/*etiology/physiopathology ; Child ; Exotropia/diagnosis/physiopathology/*surgery ; Eye Movements/*physiology ; Female ; Follow-Up Studies ; Humans ; Male ; Oculomotor Muscles/*surgery ; Ophthalmologic Surgical Procedures/*methods ; Retrospective Studies ; Treatment Outcome ; Vision, Binocular/*physiology

PURPOSE: The purpose of this study is to compare the surgical outcomes and near stereoacuities after unilateral medial rectus (MR) muscle resection and lateral rectus (LR) recession according to deviation angle in basic intermittent exotropia, X(T). METHODS: Ninety patients with basic type X(T) were included in this study. They underwent unilateral recession of the LR and resection of the MR and were followed postoperatively for at least 12 months. Patients were divided into three groups according to their preoperative deviation angle: group 1 < or =20 prism diopter (PD), 20 PD< group 2 <40 PD, and group 3 > or =40 PD. Surgical outcomes and near stereoacuities one year after surgery were evaluated. Surgical success was defined as having a deviation angle range within +/-10 PD for both near and distance fixation. RESULTS: Among 90 patients, groups 1, 2, and 3 included 30 patients each. The mean age in groups 1, 2, and 3 was 9.4 years, 9.4 years, and 11.0 years, respectively. The surgical success rates one year after surgery for groups 1, 2, and 3 were 80.0%, 73.3%, and 73.3% (chi-square test, p = 0.769), respectively. The undercorrection rates for groups 1, 2, and 3 were 16.7%, 23.3%, and 26.7%, and the overcorrection rates were 3.3%, 3.3%, and 0%, respectively. The mean preoperative near stereoacuities for groups 1, 2, and 3 were 224.3 arcsec, 302.0 arcsec, and 1,107.3 arcsec, and the mean postoperative near stereoacuities were 218.3 arcsec, 214.7 arcsec, and 743.0 arcsec (paired t-test; p = 0.858, p = 0.379, p = 0.083), respectively. CONCLUSIONS: In basic X(T) patients, the amount of angle deviation has no influence on surgical outcomes in unilateral LR recession and MR resection. The near stereoacuities by one year after LR recession and MR resection for intermittent X(T) were not different among patient groups separated by preoperative deviation angle.
Child ; Exotropia/physiopathology/*surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Oculomotor Muscles/physiopathology/*surgery ; *Ophthalmologic Surgical Procedures ; Retrospective Studies ; Treatment Outcome ; Vision, Binocular/physiology ; Visual Acuity/physiology

PURPOSE: This study was conducted to identify the relationship between control grade, stereoacuity and surgical success in basic intermittent exotropia. METHODS: This retrospective study involved 44 basic intermittent exotropia patients who underwent strabismus surgery and completed at least 6 months of follow-up. The 44 patients were divided into three subgroups according to their control grade: group 1 (good control group, n = 12), group 2 (fair control group, n = 18), and group 3 (poor control group, n = 14). Evaluation was done to identify the relationships between near and distance stereoacuity and control grade, and between surgical success and control grade. Surgical success was defined as ocular alignment between 5 prism diopters esodeviation and 10 prism diopters exodeviation in the primary position at the final visit. RESULTS: Mean near stereoacuity measured by the graded circle test was 57.50 seconds of arc (seconds) in group 1, 77.77 seconds in group 2, and 131.43 seconds in group 3 (p < 0.01). Mean distance steroacuity measured by Mentor B-VAT II BVS contour circle was 108.33 seconds in group 1, 148.33 seconds in group 2, and 262.82 seconds in group 3 (p < 0.01). Ten patients (83.33%) in group 1, 12 (66.67%) in group 2, and 9 (64.29%) in group 3 obtained surgical success (p = 0.28). CONCLUSIONS: In basic intermittent exotropia, better control grade was significantly accompanied by better stereoacuity. Better control grade was accompanied by higher surgical success rate but with no statistical significance.
Child ; Child, Preschool ; Exotropia/physiopathology/*surgery ; Female ; Humans ; Male ; Ophthalmologic Surgical Procedures ; Retrospective Studies ; Treatment Outcome ; *Visual Acuity

PURPOSE: This study was conducted to identify the relationship between control grade, stereoacuity and surgical success in basic intermittent exotropia. METHODS: This retrospective study involved 44 basic intermittent exotropia patients who underwent strabismus surgery and completed at least 6 months of follow-up. The 44 patients were divided into three subgroups according to their control grade: group 1 (good control group, n = 12), group 2 (fair control group, n = 18), and group 3 (poor control group, n = 14). Evaluation was done to identify the relationships between near and distance stereoacuity and control grade, and between surgical success and control grade. Surgical success was defined as ocular alignment between 5 prism diopters esodeviation and 10 prism diopters exodeviation in the primary position at the final visit. RESULTS: Mean near stereoacuity measured by the graded circle test was 57.50 seconds of arc (seconds) in group 1, 77.77 seconds in group 2, and 131.43 seconds in group 3 (p < 0.01). Mean distance steroacuity measured by Mentor B-VAT II BVS contour circle was 108.33 seconds in group 1, 148.33 seconds in group 2, and 262.82 seconds in group 3 (p < 0.01). Ten patients (83.33%) in group 1, 12 (66.67%) in group 2, and 9 (64.29%) in group 3 obtained surgical success (p = 0.28). CONCLUSIONS: In basic intermittent exotropia, better control grade was significantly accompanied by better stereoacuity. Better control grade was accompanied by higher surgical success rate but with no statistical significance.
Child ; Child, Preschool ; Exotropia/physiopathology/*surgery ; Female ; Humans ; Male ; Ophthalmologic Surgical Procedures ; Retrospective Studies ; Treatment Outcome ; *Visual Acuity

PURPOSE: To evaluate the correlation of the distance Krimsky test and the alternate prism cover test (APCT) for the distance deviation in patients with horizontal strabismus. METHODS: Forty patients with horizontal strabismus (20 esotropia and 20 exotropia) were included in this study. Patients with a variable angle of deviation, vertical angle over 5 prism diopters, impaired binocular vision, or poor cooperation were excluded. We instructed the patient to look a target 6 meters away, and applied a prism over the patient's dominant eye while flashing a light source 33 centimeters from the middle of both eyebrows. When the corneal light reflexes were located on the center of each cornea, we measured the angle of deviation. We defined this method as 'distance Krimsky test,' and the angle measured by this method was compared with the conventional Krimsky test and APCT at distance. We analyzed the accuracy and intra- and inter-observer reliability. RESULTS: The angle of strabismus measured by the distance Krimsky test showed a significant agreement and correlation with the deviation angle measured by the APCT. We elicited the correlation gradient between the angle measured by the distance Krimsky test and the APCT. In addition, the distance Krimsky test showed significant intra- and inter-observer reliabilities. CONCLUSIONS: The distance Krimsky test is expected to be more useful than the Krimsky test in measuring the distance angle of deviation for patients with strabismus in whom it is difficult to measure the angle of deviation using the APCT. The distance Krimsky test can be an accurate and useful test through the improvement of proficiency of examiners and the establishment of individualized normative data.
Adolescent ; Adult ; Child ; Esotropia/*diagnosis/physiopathology ; Exotropia/*diagnosis/physiopathology ; Female ; Humans ; Male ; Observer Variation ; Social Distance ; Strabismus/diagnosis/physiopathology ; Vision Tests/*methods/standards/statistics & numerical data ; Vision, Binocular ; Young Adult

PURPOSE: To investigate the symptoms of attention deficit hyperactivity disorder (ADHD) as reported by parents in children with intermittent exotropia [X(T)] and to determine whether strabismus surgery for X(T) affects ADHD symptoms. MATERIALS AND METHODS: Fifty-one consecutive children undergoing muscle surgery for X(T) were prospectively recruited. One parent of each child completed the ADHD rating scale IV (ADHD RS-IV) assessment consecutively before and one year after surgery. Patients whose preoperative scores were above the cut-off point, the 90th percentile based on a Korean sample, were regarded as demonstrating the ADHD trait. The impact of muscle surgery on ADHD symptoms was assessed by comparing the preoperative scores with the post-operative scores. RESULTS: Eight (15.7%) of the 51 patients demonstrated the ADHD trait. ADHD RS-IV scores following strabismus surgery significantly decreased in patients with the ADHD trait (p=0.014), while they did not differ in patients without the ADHD trait. Seven (87.5%) of the 8 patients with the ADHD trait showed improvement in their ADHD RS-IV scores after surgery. There was no difference in surgical success rates between X(T) patients with and without the ADHD trait. CONCLUSION: The ADHD trait was relatively common in children with X(T), and the parent-reported symptoms of the children with the ADHD trait improved after strabismus surgery. These results suggest that childhood X(T) may be one contributing factor to ADHD-related symptoms.
Attention Deficit Disorder with Hyperactivity/*diagnosis ; Child ; Child, Preschool ; Exotropia/*physiopathology ; Female ; Humans ; Male ; *Parents ; Strabismus/*surgery

PURPOSE: To analyze the postoperative strabismic angle for five years or more and to investigate when the angle stabilized in intermittent exotropia. METHODS: We retrospectively reviewed the clinical records of 89 patients who had undergone surgery for intermittent exotropia. The postoperative strabismic angles measured were analyzed at one-year intervals up to five years postoperatively. We divided them into two groups according to their age at the time of surgery. Group 1 was less than 5 years of age, while Group 2 participants were 5 years of age or older. RESULTS: For our 89 total patients, average exo-angles were 7.8 +/- 7.26, 7.9 +/- 7.51, 9.5 +/- 7.05, 10.1 +/- 6.87, and 9.4 +/- 6.90 prism diopters at one, two, three, four, and five years postoperatively, respectively. Average exo-angles between postoperative year one and year three, as well as between postoperative year two and year three, were statistically significant (p = 0.015, 0.022). However, the angles were not statistically significant between postoperative year three and year four or between years three and five, respectively (p = 0.707, p = 0.948). The stabilization characteristics of the angle were somewhat different according to age group. In Group 1, the average exo-angle in postoperative years one and three were statistically significant (p = 0.016), but the angle in the same period was not statistically significant in Group 2 (p = 0.203). CONCLUSIONS: There was no significant interval change after three years postoperatively in intermittent exotropia, but if the patient's age at surgery was 5 years or higher, no significant change of exo-angle was found following postoperative year one in this study.
Adolescent ; Child ; Child, Preschool ; Exotropia/physiopathology/*surgery ; Eye Movements/*physiology ; Female ; Follow-Up Studies ; Humans ; Male ; Oculomotor Muscles/physiopathology/*surgery ; Postoperative Period ; *Recovery of Function ; Retrospective Studies ; Treatment Outcome

PURPOSE: To evaluate the changes of refractive astigmatism after horizontal rectus muscle surgery in intermittent exotropic children. METHODS: Sixty-nine exotropic patients were retrospectively reviewed. Of those, 35 patients received unilateral lateral rectus recession (BLR group, 35 eyes) and 34 patients received unilateral lateral rectus recession and medial rectus resection (R&R group, 34 eyes). Non-cycloplegic refractions were measured until 6 months postoperatively. Spherical equivalent (SE), J0 and J45 using power vectors were calculated to determine and compare the changes of refractive astigmatism and axis in both groups. RESULTS: SE significantly decreased after surgery for the first week and did not changed thereafter in both groups (p = 0.000 and p = 0.018, respectively). In BLR group, J0 showed significant changes at the first week and 1 month after surgery (p = 0.005 and p = 0.016, respectively), but in R&R group, J0 changed significantly between 1 week and 3 months postoperatively (p = 0.023 and p = 0.016, respectively). J45 did not change significantly as time passed in both groups (all p > 0.05). There was no statistically significant difference in the magnitude of changes in SE, J0 and J45 between the two groups after the 6-month follow-up (p = 0.500, p = 0.244 and p = 0.202, respectively). CONCLUSIONS: Horizontal rectus muscle surgery in intermittent exotropic children tends to induce a statistically significant change in astigmatism in the with-the-rule direction and myopic shift in SE. This astigmatism change seems to occur within the first 3 months after surgery. Thus, astigmatism induced by surgery should be checked and corrected at least 3 months after horizontal strabismus surgery.
Adolescent ; Astigmatism/*etiology/physiopathology ; Child ; Child, Preschool ; Exotropia/complications/physiopathology/*surgery ; *Eye Movements ; Female ; Follow-Up Studies ; Humans ; Male ; Oculomotor Muscles/surgery ; Ophthalmologic Surgical Procedures/*methods ; Retrospective Studies ; Treatment Outcome ; Vision, Binocular/*physiology