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AIM:To investigate the short-term change of refractive error after strabismus surgeries with different extraocular muscles involved in.METHODS:The study included 64 eyes of 41 patients. Patients were divided into three groups:groupⅠ(a rectus recession, 25 eyes), group Ⅱ(a rectus recession combined its antagonistic muscle shortening, 32 eyes), group Ⅲ(a rectus recession combined its antagonistic muscle shortening and oblique resection, 7 eyes). Observation on refractive indexes and vector analysis program of spherical equivalent, spherical diopter, cylinder diopter, axis of astigmatism, corneal curvature,dk value and was performed 1d prior to surgeries and 1 and 4 wk after surgeries.RESULTS:No significant changes were noted at 1wk postoperative on spherical diopter, cylinder diopter, Kh, Kv, axis of astigmatism, corneal curvature in the centrel area in radius of 3mm, while spherical equivalent and dk value increased significantly(P=0.011; P=0.013). However, these changes were disappeared at 4wk postoperatively. Among the three groups, no significant changes were observed in group Ⅰ, while dk value were changed in group Ⅱ at 1wk postoperatively(P=0.035). Cylinder diopter, spherical equivalent, dk value of group Ⅲ significantly increased at 1wk postoperatively(P=0.022; P=0.048; P=0.014). At 4 wk postoperatively, these changes were disappeared.CONCLUSION:Strabismus surgeries can make reversible changes to the ocular refractive status. With different strabismus surgeries, the changes on the ocular refractive status are different.

Background, and Purpose: To assess the possibility of determining the insertion distance from the limbus of previously operated extraocular rectus muscles (EOM) with the Heidelberg Spectralis anterior segment optical coherence tomography (AS-OCT). Patient and Method: Subjects with a history of previous strabismus surgery underwent AS-OCT of the EOM before planned additional strabismus surgery. The EOM insertion distances from the limbus were measured pre-operatively on the AS-OCT and compared to the caliper distance measured during the strabismus surgery. Results: Ten previously operated muscles on nine subjects underwent AS-OCT before subsequent additional strabismus surgery. Four additional un-operated muscles subsequently operated on, were also imaged with the AS-OCT pre-operatively. Subject ages ranged from 13-52 years old (mean ± SD; 27.9 ± 13.2). The muscle insertion could be definitely identified in 6/10 muscles previously operated and 4/4 un-operated muscles. The difference between the two measurements of limbus to insertion in previously operated muscles was ≤1mm in 3/6, and ≤1.5mm in 6/6; ≤1mm in 4/4 un-operated muscles. Of the four insertions not readily identifiable, two revealed the presence of the muscle with scar tissue; the other two, the muscle insertions, were not visible, which showed that the muscle was at least a minimal amount from the limbus. Conclusion: Our study showed that the Heidelberg AS-OCT is capable of imaging previously operated EOM, which can give valuable information to the strabismus surgeon. The information from the AS-OCT was useful in all cases. The insertion to limbus measurements between pre-operative and intra-operative were within 1.5mm in all of the cases that the muscle insertion was able to be identified. The ability to accurately image EOM insertions has significant implications for the pre-operative procedure planning in previously operated and complicated strabismus patients. [ABSTRACT FROM AUTHOR]

Understanding and memorizing the primary, secondary, and tertiary functions of the vertical recti and oblique extraocular muscles play a decisive role in correctly diagnosing various types of strabismus, determining the location of nervous system lesions, and formulating correct treatment plans. However, for beginners, rapid learning, memorization, and application of these extraocular muscle functions are challenging. To improve the teaching of strabismus in ophthalmology and help students overcome the core learning difficulties, our team developed a gesture method based on a functional diagram of the extraocular muscles and a corresponding rhyme to teach clinical medicine students. The effects of the gesture method were determined by using in-class quizzes and self-confidence levels. Students' evaluations of the gesture method were assessed using a questionnaire survey. The gesture method significantly improved the mean scores on the tests (4.85 ± 1.65 vs. 6.31 ± 1.87 vs. 6.80 ± 1.45, all p < 0.001) and self-confidence scores (20.83 ± 4.06 vs. 27.38 ± 4.88 vs. 28.69 ± 3.53, all p < 0.001) of the students. The evaluations showed that the students were satisfied with the auxiliary memorization learning method. This new method could help students better understand and remember the function of the extraocular muscles, and is a valuable auxiliary teaching strategy., (© 2023 American Association of Clinical Anatomists and British Association of Clinical Anatomists.)

Introduction: To investigate the extraocular muscle (EOM) changes in thyroid-associated orbitopathy (TAO) on DTI and the correlations between DTI parameters and clinical features. Methods: Twenty TAO patients and 20 age- and sex-matched controls provided informed consent and were enrolled. Ten-directional DTI was acquired in orbit. Fractional anisotropy (FA), mean, axial, and radial diffusivities were obtained at medial and lateral EOMs in both orbits. EOM thickness was measured in patients using axial CT images. FA and diffusivities were compared between patients and controls. The relationships between DTI values and muscle thickness and exophthalmos were evaluated. DTI values compared between patients in active and inactive phases by clinical activity score of TAO. DTI values were also compared between acute and chronic stages by the duration of disease. Results: In medial EOM, FA was significantly lower in patients ( p < 0.001) and negatively correlated with muscle thickness ( r = −0.604, p < 0.001). Radial diffusivity was significantly higher in patients ( p = 0.010) and correlated with muscle thickness ( r = 0.349, p = 0.027). In lateral EOM, DTI values did not differ between patients and controls. In the acute stage, the diffusivities of the medial rectus EOM were increased compared with the chronic stage. DTI values of the medial and lateral rectus EOM did not differ significantly between active and inactive phases. Conclusion: DTI can be used to diagnose TAO with FA and radial diffusivity change in EOM. Diffusivities can be used to differentiate acute and chronic stage of TAO. However, DTI values showed limitation in reflecting TAO activity according to the CAS. [ABSTRACT FROM AUTHOR]