Factors influencing the therapeutic effect of hyperopic correction on esotropia in patients with partially accommodative esotropia.

OBJECTIVES: To collate data on partially accommodative esotropia (PAET) to better understand this condition's aetiology and to evaluate and predict the therapeutic effect of a hyperopic correction on PAET. METHODS: Eighty-nine consecutive patients diagnosed with PAET with a spherical equivalent (SE) refractive error >+2.50 D were included in this retrospective review. Clinical characteristics, including gender, age, SE, angle of esodeviation, accommodative convergence/accommodation (AC/A) ratio, near-distance disparity (NDD) and anatomical features of the rectus muscles were compared among different PAET subgroups. Multiple linear regression was used to identify independent factors that influenced the therapeutic effect of a hyperopic correction on esotropia. RESULTS: No significant differences were observed for the angle of esodeviation as a function of age in individuals with PAET. The incidence of SE in PAET participants >9 years old was significantly greater than in those <5 and 6-8 years of age. The therapeutic effect of hyperopic correction on esotropia was positively associated with SE both at distance and near. In addition, the limbus insertion distance (LID) of the lateral rectus (LR) muscle was positively associated with NDD at distance, but negatively associated at near. CONCLUSION: A greater incidence of hyperopia was observed in older (>9 years old) PAET patients. A hyperopic correction had a greater effect on esotropia in individuals with a higher SE, larger LID of the LR muscle and a smaller NDD.

Evaluation of the insertion distance of the medial rectus in consecutive exotropia by means of intraoperative measure and optical coherence tomography.

PURPOSE: To assess the agreement between the measurements of the distance from the medial rectus muscles insertion to the limbus measured by intra-operative spectral-domain optical coherence tomography (SD-OCT) in consecutive exotropia (cXT). METHODS: An analysis was performed on total of 14 medial rectus (MR) muscles of 14 patients who underwent surgery for the treatment of cXT. The limbus-insertion distance of the MR muscles was measured using preoperative SD-OCT and intraoperatively using a calliper. The intraclass correlation coefficient (ICC) and Bland Altman plots were calculated to determine the agreement between the two methods, as well as the correlation. RESULTS: Mean age was 36.3 ± 16.0 years (range 13-60), with 60% being women. Mean preoperative deviation was 38.7 ± 16.9 prismatic dioptres (PD) (range 16-65), being +1.3 ± 6.3 PD (range -12 to +10 PD) after surgery. Intraoperatively the MR insertion was found at 8.7 ± 2.1 mm (range 5.5-12.0) and by OCT at 7.7 ± 1.2 mm (range 5.3-10.0). The ICC showed a moderate to good agreement (0.659; 95% confidence interval: 0.157-0.885; p < 0.001), with a correlation of R = 0.792 (p = 0.011). A better agreement was observed in those MR that were less retro-inserted. CONCLUSIONS: SD-OCT is able to measure the insertion to the limbus distance of the medial rectus muscles that have been previously operated on, showing moderate to good agreement with intraoperative measurements. However, the agreement was poor in muscles with a large retro-insertion.

Evaluación de la distancia al recto medio en la exotropía consecutiva mediante tomografía de coherencia óptica y medida intraoperatoria / Evaluation of the insertion distance of the medial rectus in consecutive exotropia by means of intraoperative measure and optical coherence tomography

Propósito Valorar la concordancia de la medición intraoperatoria de la distancia de la inserción del recto medio (RM) al limbo corneal con la obtenida preoperatoriamente mediante tomografía de coherencia óptica de dominio espectral (SD-OCT) en pacientes con exotropía consecutiva (XTc). Métodos Se analizaron 14RM de 14 pacientes con XTc posquirúrgica que iban a ser reintervenidos. La distancia inserción-limbo fue medida preoperatoriamente mediante SD-OCT y de forma intraoperatoria con compás. Se calculó el coeficiente de correlación intraclase y un análisis de Bland Altman para analizar la concordancia de las medidas, estudiándose además la correlación de las mismas. Resultados La edad media fue 36,3±16,0años (rango 13-60), siendo el 57% mujeres. La desviación ocular media preoperatoria de la XT fue 38,7±16,9 dioptrías prismáticas (DP) (rango 16 a 65), siendo el resultado tras la cirugía de +1,3±6,3 DP (rango –12 a +10 DP). Intraoperatoriamente se halló la inserción del RM a 8,7±2,1mm (rango 5,5-12,0) y con OCT a 7,7±1,2mm (rango 5,3-10,0). El cociente de correlación intraclase mostró una concordancia moderada-buena (0,659; intervalo de confianza al 95%: 0,157-0,885; p<0,001), hallándose una correlación de R=0,792 (p=0,011). Se observó una mayor concordancia en aquellos RM que se hallaban menos retroinsertados. Conclusiones La SD-OCT puede ser una técnica útil para valorar la distancia de la inserción al limbo corneal de los RM previamente retroinsertados, hallándose una concordancia moderada-buena con la medida intraoperatoria. Sin embargo, la concordancia fue baja en músculos muy retroinsertados (AU)

Purpose To assess the agreement between the intraoperative measurements of the distance from the medial rectus muscles insertion to the limbus and preoperative spectral-domain optical coherence tomography (SD-OCT) in consecutive exotropia (cXT). Methods An analysis was performed on total of 14 medial rectus (MR) muscles of 14 patients who underwent surgery for the treatment of cXT. The limbus-insertion distance of the MR muscles was measured using preoperative SD-OCT and intraoperatively using a calliper. The intraclass correlation coefficient (ICC) and Bland Altman plots were calculated to determine the agreement between the two methods, as well as the correlation. Results Mean age was 36.3±16.0 years (range 13-60), with 60% being women. Mean preoperative deviation was 38.7±16.9 prismatic dioptres (PD) (range 16 to 65), being +1.3±6.3 PD (range -12 to +10 PD) after surgery. Intraoperatively the MR insertion was found at 8.7±2.1mm (range 5.5 - 12.0) and by OCT at 7.7±1.2mm (range 5.3 - 10.0). The ICC showed a moderate to good agreement (0.659; 95% confidence interval: 0.157-0.885; P<.001), with a correlation of R=0.792 (P=.011). A better agreement was observed in those MR that were less retro-inserted. Conclusions SD-OCT is able to measure the insertion to the limbus distance of the medial rectus muscles that have been previously operated on, showing moderate to good agreement with intraoperative measurements. However, the agreement was poor in muscles with a large retro-insertion (AU)

Evaluation of the insertion distance of the medial rectus in consecutive exotropia by means of intraoperative measure and optical coherence tomography. / Evaluación de la distancia al recto medio en la exotropía consecutiva mediante tomografía de coherencia óptica y medida intraoperatoria.

PURPOSE: To assess the agreement between the intraoperative measurements of the distance from the medial rectus muscles insertion to the limbus and preoperative spectral-domain optical coherence tomography (SD-OCT) in consecutive exotropia (cXT). METHODS: An analysis was performed on total of 14 medial rectus (MR) muscles of 14 patients who underwent surgery for the treatment of cXT. The limbus-insertion distance of the MR muscles was measured using preoperative SD-OCT and intraoperatively using a calliper. The intraclass correlation coefficient (ICC) and Bland Altman plots were calculated to determine the agreement between the two methods, as well as the correlation. RESULTS: Mean age was 36.3±16.0 years (range 13-60), with 60% being women. Mean preoperative deviation was 38.7±16.9 prismatic dioptres (PD) (range 16 to 65), being +1.3±6.3 PD (range -12 to +10 PD) after surgery. Intraoperatively the MR insertion was found at 8.7±2.1mm (range 5.5 - 12.0) and by OCT at 7.7±1.2mm (range 5.3 - 10.0). The ICC showed a moderate to good agreement (0.659; 95% confidence interval: 0.157-0.885; P<.001), with a correlation of R=0.792 (P=.011). A better agreement was observed in those MR that were less retro-inserted. CONCLUSIONS: SD-OCT is able to measure the insertion to the limbus distance of the medial rectus muscles that have been previously operated on, showing moderate to good agreement with intraoperative measurements. However, the agreement was poor in muscles with a large retro-insertion.

Measurement of extraocular horizontal muscle insertion distance via anterior segment optical coherence tomography of healthy children and comparison with healthy adults.

PURPOSE: The aim of the study was to determine the corneal limbus-extraocular muscle insertion distance (LID), via anterior segment optical coherence tomography, in healthy children and healthy adults and to compare the results of the measurements of the two groups. METHODS: Muscle limbus distances were measured using AS-OCT in 60 healthy cases in two groups. Children aged 8-13 years were evaluated as group 1, and healthy adults aged 25-30 years were evaluated as group 2. Measurements of 120 horizontal muscles were taken by one doctor (OBO). The values were compared according to age and gender groups, and correlation between LID measurements and spherical equivalent. Statistical evaluation was performed using SPSS 16® for Windows with the Student's t test and Pearson correlation coefficient test. RESULTS: LID measurements for MR and for lateral rectus (LR) were 5.74 ± 0.75 and 6.74 ± 1.11 mm, in the pediatric age-group, and 5.73 ± 0.75 and 6.84 ± 1.15 mm, in the adult age-group, respectively. There was no statistically significant difference between the two groups in terms of MR distances. There was a slight increase in the adult values, for the LR distance. There was no significant difference in terms of gender. Correlation was found 0.62 for MR and 0.46 for LR between LID measurements and spherical equivalent in the pediatric age-group. CONCLUSIONS: In healthy individuals, different imaging modalities can be used to measure LID, but AS-OCT can be used in pediatric age-groups as a preferred imaging method because it is easy and noninvasive.

Agreement between intraoperative measurements and optical coherence tomography of the limbus-insertion distance of the extraocular muscles. / Concordancia de la distancia desde la inserción hasta el limbo de los músculos rectos entre la medida intraoperatoria y con tomografía de coherencia óptica.

OBJECTIVE: To assess the agreement between intraoperative measurements of the limbus-insertion distance of the extraocular muscles with those measured by spectral domain optical coherence tomography. METHODS: An analysis was made of a total of 67 muscles of 21 patients with strabismus. The limbus-insertion distance of the horizontal rectus muscles were measured using pre-operative SD-OCT and intra-operatively in 2 ways: 1) direct, after a conjunctival dissection in patients who underwent surgery, or 2) transconjunctival in patients who were treated with botulinum toxin, or in those who were not going to be operated. The intraclass correlation coefficient and Bland-Altman plots were calculated to determine the concordance between the 2 methods. RESULTS: The mean age was 45.9 ±20.9 years (range 16 to 85), with 52% being women. The percentage of identification by direct intraoperative measurement was 95.6% (22/23), by transconjunctival intraoperative measurement 90.9% (40/44), and by OCT 85% (57/67), with 22 muscles finally being analysed for the agreement study between direct intraoperative measurement and OCT measurements, and 35 muscles for the agreement between transconjuctival intraoperative measurement and OCT. The intraclass correlation coefficient showed good agreement with OCT and direct intraoperative measurements (0.931; 95% confidence interval (95% CI): 0.839-0.972; P<.001), and with transconjunctival intraoperative measurements (0.889; 95% CI: 0.790-0.942; P<.001). CONCLUSIONS: The SD-OCT is an effective technique to measure the distance from the insertion of the horizontal rectus muscles to the limbus, with a high agreement with intraoperative measurements being demonstrated.

Anatomical Evaluation of Extraocular Muscles and Relationships Among Macula and Optic Nerve in Enucleated Eye

PURPOSE: To make an anatomical evaluation of extraocular muscles, macular and optic nerve in enucleated eyes of live subjects and to compare the results with a previous autopsy study. METHODS: Twenty-four surgically enucleated eyes were studied. The distance from the limbus to the muscle insertion site, muscle width, and the distance between muscle insertion sites were measured and compared with an Apt study. After an incision through the eyeball, a 26-gauge needle was passed perpendicularly through the macula to the sclera. We measured the distances between the oblique muscles and the macula and optic nerves from an external site of the eyeball. RESULTS: The distance from the limbus to the muscle insertion site showed a significant difference in the superior and inferior rectus muscle. All measurements of muscle widths were significantly narrower than those of autopsy studies. The distances between the muscles were significantly closer between the lateral and superior muscles and between the superior and medial rectus muscles. From the optic nerve to the muscle was 3.99+/-0.62 mm, to the superior oblique muscle was 7.89+/-0.88 mm, to the inferior oblique muscle was 5.95+/-0.83 mm, and the macula to the inferior oblique muscle was 1.35+/-0.42 mm. CONCLUSIONS: Since most of the measurements were different from those of autopsy studies, we should consider the effects of preservation and fixation solution on autopsy eyes, race, and the differences among measurement instruments.

Anatomical Evaluations of The Location and Insertion Shape of Horizontal Rectus Muscle

We examined the variations in the limbus-insertion distance, the width and the insertion shape of 260 horizontal recti muscles in 137 strabismic patients, and evaluated the relationship between insertion shape and postoperative results. The average limbus-insertion distance of medial rectus muscle was 4.72 +/- 0.49mm and that of lateral rectus muscle was 6.29 +/- 0.58mm. The width of medial rectus and lateral rectus mascle was 9.84 +/- 0.83mm and 9.57 +/- 0.84mm. The insertion shapes of horizontal rectus muscle were divided into 5 groups, straight, oblique type I and II, concave and convex patterns. According to insertion shape, insertion shape of the medial rectus muscle had no statistic difference in esotropia and exotropia(P=0.179), but in case of the lateral rectus muscle, it was staistically significant in both exotropia and esotropia(P=0.036). When the deviation angle was larger than 40 delta, the length of limbus width was statistically significant in lateral rectus muscle(P=0.018). The insertion shape divided into straight and non-straight pattern was statistically insignificant on postoperative success rate.

Insertion of Horizontal Rectus Muscles in Strabismus

An anatomical evaluation of the limbus-insertion distance and width at insertion of the horizontal rectus muscle had been measured on enuclated eyes from normal adult cadavers by several authors. We measured the variation in the limbus-insertion distance and width of 214 horizontal rectus muscles in 111 strabismus patients, composed of 38 esotropes and 73 exotropes. We also evaluated their relation to strabismus. The results were as follows: 1. The average limbus-insertion distance of medial rectus was 4.38 +/- 0.45 mm and lateral rectus was 5.56 +/- 0.84 mm and the average width of medial rectus at insertion was 9.19 +/- 0.78 mm and that of lateral was 8.32 +/- 1.00 mm. 2. The largest values for limbus-insertion distance and width of medial rectus were found in esotropes in the 8 to 13 years old age group(9.76 +/- 0.12 mm and 4.53 +/- 0.44 mm respectively), and those of lateral rectus in exotropes in the 13 to 18 years old age group(8.66 +/- 0.95mm and 6.09 +/- 0.45mm respectively). 3. The limbus-insertion distance and width at insertion was larger in male than in female and it was especially significant in the medial rectus muscle of esotropes(p<0.001). 4. The limbus-insertion distance and width tended to be larger in horizontal deviation greater than 40 delta. as compared to those of 40 delta or less.