An Overview of the Korean Intermittent Exotropia Multicenter Study by the Korean Association for Pediatric Ophthalmology and Strabismus

The Korean Intermittent Exotropia Multicenter Study (KIEMS), which was initiated by the Korean Association of Pediatric Ophthalmology and Strabismus, is a collaborative multicenter study on intermittent exotropia in Korea. The KIEMS was designed to provide comprehensive information, including subjective and objective findings of intermittent exotropia in a large study population. A total of 65 strabismus specialists in 53 institutions contributed to this study, which, to date, is one of the largest clinical studies on intermittent exotropia. In this article, we provide a detailed methodology of the KIEMS to help future investigations that may use the KIEMS data.

An Overview of the Korean Intermittent Exotropia Multicenter Study by the Korean Association for Pediatric Ophthalmology and Strabismus

The Korean Intermittent Exotropia Multicenter Study (KIEMS), which was initiated by the Korean Association of Pediatric Ophthalmology and Strabismus, is a collaborative multicenter study on intermittent exotropia in Korea. The KIEMS was designed to provide comprehensive information, including subjective and objective findings of intermittent exotropia in a large study population. A total of 65 strabismus specialists in 53 institutions contributed to this study, which, to date, is one of the largest clinical studies on intermittent exotropia. In this article, we provide a detailed methodology of the KIEMS to help future investigations that may use the KIEMS data.

Differences in Retinal and Choroidal Vessels between Dominant and Non-dominant Eyes in Intermittent Exotropia

Purpose@#To distinguish the dominant eye in patients with intermittent exotropia by comparing the width of the foveal avascular zone (FAZ), the vascular density (VD), and the choroidal thickness (CT) in both eyes. @*Methods@#A total of 34 subjects with intermittent exotropia were enrolled. Optical coherence tomography angiography (OCTA) was performed after discrimination of the dominant eye using a prism cover test (PCT). FAZ widths in the superficial capillary plexus (referred to here as superficial FAZ or SFAZ) and in the deep capillary plexus (deep FAZ or DFAZ); VDs of the 1-mm fovea and 3-mm parafovea, specifically the superficial capillary plexus density (SCPD); and CT measured by OCTA were compared between both eyes using a one-sample t-test. These abovementioned parameters were compared between dominant and non-dominant eyes through Pearson’s correlation analysis. @*Results@#The widths of SFAZ and DFAZ, the 1-mm fovea and 3-mm parafovea SCPDs, and CT of dominant eye showed positive correlations with respect to the non-dominant eye. Although there was no statistically significant difference in SFAZ and DFAZ widths, the 3-mm parafovea SCPD, or CT between eyes, the 1-mm fovea SCPD in the non-dominant eye showed a statistically significant higher density than that of the dominant eye (p = 0.039). @*Conclusions@#Our results suggest that the higher 1-mm fovea SCPD in the non-dominant eye is due to the secondary development of capillaries around the FAZ of the non-dominant eye after the retina of both eyes had developed to some extent.

Differences in Retinal and Choroidal Vessels between Dominant and Non-dominant Eyes in Intermittent Exotropia

Purpose@#To distinguish the dominant eye in patients with intermittent exotropia by comparing the width of the foveal avascular zone (FAZ), the vascular density (VD), and the choroidal thickness (CT) in both eyes. @*Methods@#A total of 34 subjects with intermittent exotropia were enrolled. Optical coherence tomography angiography (OCTA) was performed after discrimination of the dominant eye using a prism cover test (PCT). FAZ widths in the superficial capillary plexus (referred to here as superficial FAZ or SFAZ) and in the deep capillary plexus (deep FAZ or DFAZ); VDs of the 1-mm fovea and 3-mm parafovea, specifically the superficial capillary plexus density (SCPD); and CT measured by OCTA were compared between both eyes using a one-sample t-test. These abovementioned parameters were compared between dominant and non-dominant eyes through Pearson’s correlation analysis. @*Results@#The widths of SFAZ and DFAZ, the 1-mm fovea and 3-mm parafovea SCPDs, and CT of dominant eye showed positive correlations with respect to the non-dominant eye. Although there was no statistically significant difference in SFAZ and DFAZ widths, the 3-mm parafovea SCPD, or CT between eyes, the 1-mm fovea SCPD in the non-dominant eye showed a statistically significant higher density than that of the dominant eye (p = 0.039). @*Conclusions@#Our results suggest that the higher 1-mm fovea SCPD in the non-dominant eye is due to the secondary development of capillaries around the FAZ of the non-dominant eye after the retina of both eyes had developed to some extent.

Implementing Medical Education Continuous Quality Improvement Using Design‐Based Research / 의학교육논단

The goal of this study is to present efficient measures to improve the quality of medical education through using a developed and applied continuous quality improvement (CQI) model suitable for medical education.To achieve this purpose, we developed a theoretical CQI model through a review of the literature according to the design-based research method. Through repetitive productive cyclical processes and professional reviews, we finally deduced an appropriate CQI model for medical education. The most important results of this study are as follows: First, the CQI model for medical education is defined as a quality management system with a cyclical course of planning, implementation, evaluation, and improvement of medical education.Second, the CQI model for medical education is composed of quality management activities of educational design, work, and evaluation. In addition, each activity has the implementation strategies of planning, doing, checking, and improving based on the PDCA model (Plan-Do-Check-Act model). Third, the CQI model for medical school education is composed of committees related to medical education doing improvement activities, as well as planning, implementing and evaluating it with CQI. As a result, we can improve teaching by using the CQI model for medical education. It is more meaningful because this gives us organized and practical measures of quality management and improvement in medical education as well as in the educational process.

The Development of Mission and Vision Using Delphi Method in a Medical School / 계명의대학술지

The mission of an organization defines the fundamental reason for the organization's existence and serves as a compass that leads and guides the organization. This study aimed to develop a system regarding mission and vision in accordance with the value system of organizations. The Delphi questionnaires were formulated in such a way to reflect an open survey for the first survey and then a structured survey in the second survey. The validity of the Delphi survey results was analyzed using the content validity ratio (CVR).Missions include the reason for the existence of an organization and its management purpose. A vision is a blueprint that outlines the future roles and goals of an organization beyond its current position. Then, a strategy is seen as a method to achieve the mission and vision. Values are consistent principles and tenet. This study found through the web sites of all 40 medical schools that 9 schools (22.5%) had both missions and visions, 10 schools (25.0%) had only one of them, and 21 schools (52.5%) had none of them. this study recommends the inclusion of various stakeholder, the selection of a mission system, modification or improvements after re-analyzing the relationship, the use of the Delphi method, proofreading of the draft by Korean language experts, the suitability and notify about the mission development to medical school members.

The Development of Mission and Vision Using Delphi Method in a Medical School / 계명의대학술지

The mission of an organization defines the fundamental reason for the organization's existence and serves as a compass that leads and guides the organization. This study aimed to develop a system regarding mission and vision in accordance with the value system of organizations. The Delphi questionnaires were formulated in such a way to reflect an open survey for the first survey and then a structured survey in the second survey. The validity of the Delphi survey results was analyzed using the content validity ratio (CVR).Missions include the reason for the existence of an organization and its management purpose. A vision is a blueprint that outlines the future roles and goals of an organization beyond its current position. Then, a strategy is seen as a method to achieve the mission and vision. Values are consistent principles and tenet. This study found through the web sites of all 40 medical schools that 9 schools (22.5%) had both missions and visions, 10 schools (25.0%) had only one of them, and 21 schools (52.5%) had none of them. this study recommends the inclusion of various stakeholder, the selection of a mission system, modification or improvements after re-analyzing the relationship, the use of the Delphi method, proofreading of the draft by Korean language experts, the suitability and notify about the mission development to medical school members.

The Development of Mission and Vision Using Delphi Method in a Medical School / 계명의대학술지

The mission of an organization defines the fundamental reason for the organization's existence and serves as a compass that leads and guides the organization. This study aimed to develop a system regarding mission and vision in accordance with the value system of organizations. The Delphi questionnaires were formulated in such a way to reflect an open survey for the first survey and then a structured survey in the second survey. The validity of the Delphi survey results was analyzed using the content validity ratio (CVR).Missions include the reason for the existence of an organization and its management purpose. A vision is a blueprint that outlines the future roles and goals of an organization beyond its current position. Then, a strategy is seen as a method to achieve the mission and vision. Values are consistent principles and tenet. This study found through the web sites of all 40 medical schools that 9 schools (22.5%) had both missions and visions, 10 schools (25.0%) had only one of them, and 21 schools (52.5%) had none of them. this study recommends the inclusion of various stakeholder, the selection of a mission system, modification or improvements after re-analyzing the relationship, the use of the Delphi method, proofreading of the draft by Korean language experts, the suitability and notify about the mission development to medical school members.

Horizontal Extraocular Muscle and Scleral Anatomy in Children: A Swept-Source Anterior Segment Optical Coherence Tomography Study

PURPOSE: To evaluate the efficacy of anterior segment swept-source optical coherence tomography (SS-OCT) for examining horizontal extraocular muscle thickness, distance from the corneal limbus to the insertion of the horizontal extraocular muscle (limbus to insertion distance), and scleral thickness in Korean pediatric strabismus patients. METHODS: This study included pediatric strabismus patients between 5 and 10 years of age. Children with any ocular disease other than strabismus or a history of ocular surgery were excluded. SS-OCT was used to measure horizontal extraocular muscle thickness, limbus to insertion distance, and scleral thickness. Eyes were classified into subgroups by sex, spherical equivalent of the refractive error (measured with cycloplegic refraction), and fixating/deviating eye. RESULTS: One patient initially included in this study was excluded due to poor cooperation. Of the remaining 35 eyes of 20 patients, 19 eyes (54.3%) were from male patients and 16 eyes (45.7%) were from female patients. The mean patient age was 7.86 ± 1.38 years. Lateral scleral thickness was greater in male eyes than in female eyes (p = 0.048). No other differences were noted between male and female children. Additionally, there were no statistically significant differences between fixating and deviating eyes or among spherical equivalent groups for any parameter examined. CONCLUSIONS: Anterior segment SS-OCT can successfully and comfortably measure horizontal extraocular muscle and scleral anatomy in children. These measurements may be helpful for treatment and follow-up of pediatric strabismus patients.

Comparison of Long-term Surgical Outcomes of Two-muscle Surgery in Basic-type Intermittent Exotropia: Bilateral versus Unilateral

PURPOSE: To compare long-term surgical outcomes after bilateral lateral rectus recession (BLR) and unilateral lateral rectus recession-medial rectus resection (RR) for the treatment of basic-type intermittent exotropia. METHODS: Consecutive patients who underwent BLR or RR for treatment of intermittent exotropia between 1999 and 2010 and underwent ≥5 years of follow-up were recruited for this study. Surgical outcomes were grouped according to postoperative angle of deviation: overcorrection (esophoria/tropia >8 prism diopters [Δ]), success (esophoria/tropia ≤8Δ to exophoria/tropia ≤8Δ), and undercorrection/recurrence (exophoria/tropia >8Δ). Outcomes were compared between the BLR group and the RR group at postoperative week 1, months 1 and 6, and years 1, 2, 3, 4, and 5. RESULTS: Of 99 patients, 37 underwent BLR and 62 underwent RR. At postoperative month 6 (97.3% vs. 82.3%, p = 0.045) and year 1 (91.9% vs. 74.2%, p = 0.040), the surgical success rates in the BLR group were significantly higher than in the RR group. Recurrence of exophoria/tropia most commonly occurred between 2 and 3 years after surgery in the BLR group, but continuous recurrences were found in the RR group. At postoperative year 5, the surgical success rate was 54.1% in the BLR group and 41.9% in the RR group (p = 0.403). The reoperation rate was 24.3% in the BLR group and 33.9% in the RR group (p = 0.317). CONCLUSIONS: Surgical outcomes 5 years after surgery for intermittent exotropia were comparable between the BLR and RR groups. The surgical success rate and the reoperation rate were not significantly different between the BLR and RR groups.

Clinical Analysis of Factors Affecting Successful Occlusion Treatment and Visual Recovery Time in Amblyopia

PURPOSE: To evaluate the factors affecting successful occlusion treatment and visual recovery time in patients with amblyopia when best corrected visual acuity (BCVA) improved up to 1.0 after occlusion. METHODS: Forty-eight patients aged 2 to 13 years old with amblyopia due to refractive errors or strabismus were selected. The duration of treatment needed to achieve a BCVA of 1.0 was compared according to the cause of amblyopia (anisometropia, strabismus, combined), initial BCVA of the amblyopic eye, and the age at treatment, as well as other factors. RESULTS: The mean age of amblyopic treatment was 5.4 years old and the mean duration of treatment was 22.9 months. The duration of treatment was longer in children whose initial BCVA was lower than 0.2, those with spherical equivalent of the amblyopic eye higher than +3.0D and those older than 6 years old. However, there were no significant differences according to the cause of amblyopia. CONCLUSIONS: The duration of treatment needed to achieve a BCVA of 1.0 was prolonged when the initial BCVA in the amblyopic eye was lower than 0.2, the age at treatment was more than 6 years old, or the spherical equivalent of the amblyopic eye was higher than +3.0D at treatment. These factors can be used to predict the duration of occlusion treatment.

Comparison of Postoperative Exodrift after First Unilateral and Second Contralateral Lateral Rectus Recession in Recurrent Exotropia

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.

The Surgical Outcome and Stereopsis between Pseudodivergence Excess Type and Convergence Insufficiency Type

PURPOSE: To compare the surgical outcomes and stereopsis between pseudodivergence excess type and convergence insufficiency type in intermittent exotropia. METHODS: In a retrospective comparative analysis of 42 eyes, 18 eyes that were of the convergence insufficiency type (group 1) and 24 eyes that were or the pseudodivergence excess type (group 2) were analyzed. Recession-resection was performed in the same eye. Success was defined to be within ±8 PD after 12 months postoperatively; more than ±8 PD was defined as recurrence. Stereopsis was measured by the Titmus test. RESULTS: After the patch test, the mean preoperative near angle in group 1 was 35.56 ± 6.62 PD and the far angle was 23.06 ± 6.22 PD. In group 2, the mean preoperative near angle was 26.92 ± 6.30 PD and the far angle was 28.29 ± 7.41 PD. The group 1 postoperative (12 months) mean near angle was 6.89 ± 8.46 PD and the far angle was 6.11 ± 7.90 PD. In group 2, the mean postoperative near angle was 1.75 ± 2.85 PD and the far angle was 3.42 ± 3.98 PD. The success rate of group 1 was 50% and the success rate of group 2 was 83.3%. The success rate of both group were statistically significant differences (p = 0.021). The postoperative (12 months) mean of near stereopsis for group 1 was 588 ± 1,124 seconds, and group 2 was 101.25 ± 102 seconds. There were no statistically differences in postoperative (12 months) stereopsis. CONCLUSIONS: The success rate of the pseudodivergence excess type was significantly higher than in the convergence insufficiency type.

Diagnostic Availability of Blind Spot Mapping for Ocular Torsion

PURPOSE: To evaluate diagnostic the usefulness of blind spot mapping in measuring ocular torsion changes and to investigate the correlations of inferior oblique muscle overaction (IOOA) and excyclotorsion measurements using fundus photographs and blind spot mapping in patients with secondary IOOA. METHODS: Eleven patients (12 eyes; IOOA group) diagnosed with secondary IOOA were evaluated for ocular movement, fundus photograph and Humphrey standard automated perimetry, and 10 patients (20 eyes; control group) were subjected to the same tests. An ocular movement examination was performed to evaluate IOOA, and fundus photograph and Humphrey standard automated perimetry were used to measure the ocular torsion. Inferior oblique myectomy or recession was performed along with horizontal strabismus surgery, and preoperative and postoperative IOOA and ocular torsion measurements were compared between the groups. RESULTS: In the IOOA group after surgery, the IOOA decreased from +2.42 ± 0.63 to +0.50 ± 0.52, the ocular torsion decreased from +14.15 ± 3.60° to +7.47 ± 1.65° (p < 0.001) on fundus photographs, and from +12.19 ± 1.62° to +9.69 ± 1.75° (p = 0.061) in Humphrey standard automated perimetry. The control group showed a mean ocular torsion of 7.44 ± 1.62° on fundus photographs and +7.24 ± 1.28° on Humphrey standard automated perimetry. CONCLUSIONS: The usefulness of blind spot mapping when the ocular torsion was measured in IOOA patients was considered low, due to the weak correlation between IOOA and extorsion; preoperative and postoperative ocular torsion amount values were not significantly different.

The Surgical Outcomes of Unilateral Lateral Rectus Recession in Recurrent Intermittent Exotropia after Unilateral Recession-Resection

PURPOSE: To evaluate the surgical outcomes of unilateral lateral rectus (LR) recession on the contralateral eye for recurrent intermittent exotropia after unilateral recession-resection (R & R). METHODS: A retrospective analysis of 43 patients was performed. The patients were classified into 2 groups, 18 patients who underwent unilateral LR recession for intermittent exotropia of 18 to 20 prism diopters (PD) after unilateral R & R (reoperation group) and 25 patients who had primary unilateral LR recession (primary operation group). RESULTS: Significant differences in age, gender, refractive error, preoperative deviation, and near stereoacuity were not observed between the 2 groups (p > 0.05). The mean follow-up duration was 14.28 +/- 14.98 months in the reoperation group and 14.68 +/- 12.15 months in the primary operation group. Postoperative deviations were 1.11 +/- 3.89 PD at near distance and 2.00 +/- 4.70 PD at far distance in the reoperation group and 6.44 +/- 5.26 PD at near distance and 7.00 +/- 5.77 PD at far distance in the primary operation group on the final follow-up (p = 0.000, p = 0.004). The final surgical successful rates were 94.4% in the reoperation group and 64.0% in the primary group (p = 0.021). CONCLUSIONS: The long-term surgical results of unilateral LR recession on the contralateral eye was better in patients with recurrent intermittent exotropia of 18 to 20 PD after unilateral R & R than patients who had primary unilateral LR recession.

Comparison of Surgical Outcomes with Unilateral Recession and Resection According to Angle of Deviation in Basic Intermittent Exotropia

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 =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.

Relationship between Control Grade, Stereoacuity and Surgical Success in Basic Intermittent Exotropia

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.

Relationship between Control Grade, Stereoacuity and Surgical Success in Basic Intermittent Exotropia

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.

Comparison of Surgical Outcomes in Patients with Small Refractive Error and Intermittent Exotropia

PURPOSE: To identify differences in the refractive error of postoperative intermittent exotropia patients. METHODS: A total of 71 patients who had an average refractive error of 2 D and a follow-up of more than 6 months after unilateral recession-resection (R&R) for intermittent exotropia were included in this study. Patients were divided into 3 groups according to their refractive error: Group 1, or =+1.0 D. The amounts of deviation 1 day after surgery and 6 months after surgery were evaluated. RESULTS: Out of the 71 total patients included in this study, group 1 included 20 patients, group 2 included 39, and group 3 included 12. The average refractive error in groups 1, 2, and 3 was -2.2 +/- 0.9 D, 0.0 +/- 0.4 D and +1.9 +/- 0.9 D, respectively. The angle of deviation 1 day after surgery was measured in the 3 groups; A result labeled '+' was considered to be exodeviation and a result labeled '-' was considered to be esodeviation. The angle of deviation results for groups 1, 2, and 3 one day after surgery were -6.7 +/- 6.0 PD, -7.5 +/- 5.8 PD and -7.3 +/- 5.9 PD (p = 0.937), respectively, and the results 6 months after surgery were +2.2 +/- 4.3 PD, +4.7 +/- 5.9 PD and +1.8 +/- 2.8 PD (p = 0.076), respectively. Among the 3 groups, no statistically significant difference was observed in postoperative angle of deviation after 6 months. CONCLUSIONS: In basic intermittent exotropia patients with an average refractive error of 2 D, the amount of refractive error makes no difference in strabismus surgical outcomes.

The Ratio of Accommodative-Convergence to Accommodation in Patients with Nonrefractive Accommodative Esotropia

PURPOSE: To measure the ratio of accommodative-convergence to accommodation (AC/A ratio) in patients with nonrefractive accommodative esotropia in comparison to refractive accommodative esotropia and normal groups. METHODS: A total of 43 subjects were divided into 3 groups: the nonrefractive accommodative esotropia group (group 1), the refractive accommodative esotropia group (group 2) and the normal group (group 3). Age, sex, age of onset, and refractive errors were recorded. The deviation angle was measured near and at distance by using a prism cover test. The AC/A ratio was calculated using a gradient method. RESULTS: Refractive errors were 2.3 +/- 1.7 D (OD) and 2.4 +/- 2.1 D (OS) in group 1, 4.8 +/- 0.9 D (OD) and 4.6 +/- 1.1 D (OS) in group 2, and -0.3 +/- 1.5 D (OD) and -0.5 +/- 1.5 D (OS) in group 3. Group 2 had higher mean refractive errors than groups 1 and 3, while the difference in refractive error between group 1 and group 3 was not statistically significant. The AC/A ratio was 5.5 in group 1, 2.1 in group 2 and 2.2 in group 3; there was no significant difference between groups 2 and 3, while group 1 had a significantly higher AC/A ratio than both of these groups. CONCLUSIONS: AC/A ratio in patients with nonrefractive accommodative esotropia is higher than that of refractive accommodative esotropia or normal children. It could be used for bifocal lens as non-surgical treatment.