Preliminary Results of New Modification of Vertical Muscle Transposition to Enhance Abducting Force in Sixth Nerve Palsy.

Introduction: Since 1907, multiple transposition procedures have been established for the treatment of abducens paralysis. The purpose of the study was to determine where the transposed muscle should be reattached in order to increase the tangential force necessary to improve abduction. Methods: Retrospective case review of 12 consecutive patients with abducens paralysis who underwent transposition procedures between 2016 and 2019 was conducted. Vertical rectus muscles are transposed to the insertion of lateral rectus muscle; the temporal parts are joined and sutured to the sclera on top of the lateral rectus muscle in the middle of the insertion. The nasal parts are sutured to the sclera following the spiral of Tillaux. The muscle junction suture is placed 8 mm from the insertion, with the temporal parts of the vertical muscles bellies joined and sutured to the lateral rectus muscle. A full-tendon transposition was performed on 11 patients, a half-tendon transposition procedure on 1 patient. The minimum follow-up was 3 months. Results: The mean preoperative deviation was ET of 37° (range: ET 24° to ET 51°). The mean preoperative abduction limitation was 5 mm from midline (range: 7 to 1 mm). The postoperative mean deviation was ET of 2° (range: 0° to ET 5°). The postoperative mean abduction improvement was 5 mm past midline (range: 2-6 mm). There were no complications or signs of anterior segment ischemia. Conclusion: To achieve the maximal abductive force from the transposed muscles, we suggest that the vertical muscles be reattached as close as possible to the middle of the lateral rectus insertion.

Factors influencing myopic shift in children after intraocular lens implantation.

INTRODUCTION: Intraocular lenses have always been a controversial topic in pediatric cataract surgery. In the early 1990s in the post-Soviet states of Eastern Europe, intraocular lenses promised an easier full-time correction and amblyopia treatment. Since 1991, ophthalmologists in Latvia have been implanting intraocular lenses in infants. Amount of the postoperative myopic shift and its influencing factors, analyzed in this article, are important indicators of congenital cataract treatment. MATERIALS AND METHODS: A retrospective chart review off 85 children (137 eyes) who underwent foldable posterior chamber intraocular lens implantation at the Clinical University Hospital in Riga, Latvia, from 1 January 2006 until 31 December 2016, was performed. Depending on the age at surgery, patients were divided into six groups: 1-6, 7-12, 13-24, 25-48, 49-84, and 85-216 months. RESULTS: The largest and more variable myopic shift was found in a group of diffuse/total and nuclear cataract with surgery before the age of 6 months. There was a statistically significant correlation between the acquired best-corrected visual acuity and the amount of myopic shift (rs = 0.33; p < 0.001). Comparing the amount of myopic shift in two groups of different intraocular lens implantation target refraction tactics, we did not find statistically significant differences. Comparing the amount of myopic shift and implanted intraocular lens power, a negative, statistically significant correlation was found. CONCLUSION: The earlier the cataract extraction surgery and intraocular lens implantation is performed, the larger the myopic shift. The morphological type of cataract, best-corrected visual acuity, secondary glaucoma, and intraocular lens power influence the amount of myopic shift.

[Foster Modification of Full Tendon Transposition of Vertical Rectus Muscles for Sixth Nerve Palsy]. / Komplette vertikale Transposition der Vertikalmotoren modifiziert nach Foster als Operationstechnik für Abduzensparese.

INTRODUCTION: Since 1907 a variety of muscle transposition procedures for the treatment of abducens nerve palsy has been established internationally. Full tendon transposition of the vertical rectus muscle was initially described by O'Connor 1935 and then augmented by Foster 1997 with addition of posterior fixation sutures on the vertical rectus muscle. Full tendon transposition augmented by Foster belongs to the group of the most powerful surgical techniques to improve the abduction. Purpose of this study was to evaluate the results of full tendon vertical rectus transposition augmented with lateral fixation suture for patients with abducens nerve palsy. METHODS AND RESULTS: Full tendon transpositions of vertical rectus muscles augmented with posterior fixation suture was performed in 2014 on five patients with abducens nerve palsy. Two of the patients received Botox injections in the medial rectus muscle: one of them three months after the surgery and another during the surgery. One of the patients had a combined surgery of the horizontal muscles one year before. On three of the patients, who received a pure transposition surgery, the preoperative deviation at the distance (mean: + 56.6 pd; range: + 40 to + 80 pd) was reduced by a mean of 39.6 pd (range 34 to 50 pd), the abduction was improved by a mean of 3 mm (range 2 to 4 mm). The other two patients, who received besides the transposition procedure additional surgeries of the horizontal muscles, the preoperative deviation at the distance (+ 25 and + 126 pd respectively) was reduced by 20 and 81 pd respectively. The abduction was improved by 4 and 8 mm respectively. After surgery two patients developed a vertical deviation with a maximum of 4 pd. None of the patients had complications or signs of anterior segment ischemia. The elevation and/or depression was only marginally affected. There was no diplopia in up- or downgaze. CONCLUSIONS: Full tendon transposition of vertical rectus muscles, augmented with lateral posterior fixation suture is a safe and effective treatment method for abducens nerve palsy and in most cases recession of the medial rectus can be avoided. Upgaze and downgaze are affected very slightly. Diverse studies have shown that the risk of anterior segment ischemia is low.

PowerRefractor versus Canon R-50 Autorefraction to assess refractive error in children: a community-based study in ecuador.

PURPOSE: To compare the agreement of the PowerRefractor with Canon R-50 autorefraction for measuring refractive error in a community of Ecuadorian children. METHODS: We examined 1564 children aged 5 to 6 years from two ethnically and geographically similar regions of the Ecuadorian highlands. Results of a refraction obtained without cycloplegia with the PowerRefractor and with the Canon R-50 autorefractor (NCAR) were compared with the gold-standard examination, cycloplegic autorefraction (CAR) with the Canon R-50 autorefractor. Power vectors were used to analyze refractive error. Bland-Altman limits of agreement were obtained. RESULTS: Although the mean difference in the spherical equivalent refractive error between the PowerRefractor and CAR was small (-0.03 D +/- 0.05 D), the 95% limits of agreement were wide (+/-2.03 D). On the other hand, NCAR showed a greater bias (0.97 D +/- 0.04 D) and smaller limits of agreement (+/-1.49 D). The limits of agreement of the PowerRefractor were also wider than NCAR for measuring astigmatism. When the mean difference was stratified by the subgroups of refractive error vectors, the PowerRefractor was found to have poorer limits of agreement than NCAR for hyperopic defects. CONCLUSION: The PowerRefractor is accurate, but not as precise for measuring refractive error as compared to the Canon R-50 autorefractor, especially for high hyperopia.

Trastornos de la motilidad ocular en una población de niños escolares de la Sierra Ecuatoriana / Ocular motility disorders in a population of school children in the Sierra Ecuatoriana

Propósito: El objetivo del siguiente trabajo fue el de determinar la prevalencia y los distintos tipos de trastornos de la motilidad ocular en una población escolar de la sierra ecuatoriana. Material y métodos: Se examinaron 6143 niños de entre 4 y 16 años de edad de dos áreas geográficas étnicamente similares de la Sierra del Ecuador. De la población examinada, 2775 fueron de sexo femenino y 3368 de sexo masculino. A cada niño se le efectuó un examen oftalmológico que comprendía: inspección, estudio de la motilidad ocular, reflejos pupilares, estereopsis, agudeza visual sin corrección y con corrección en aquellos niños portadores de lentes, examen de ojo externo, autorrefractometria y videorrefractometria. Se efectuó autorrefractometria con cicloplejia y examen de fondo de ojo a todos los niños con niveles de agudeza visual menor a 0.8 en alguno de sus ojos, a todos los niños entre 4 y 6 años y en forma randomizada al 10 por ciento del total de los niños. El examen de la motilidad ocular consistió en evaluación de la excursión ocular hacia las 9 posiciones de la mirada, Cover test para lejos y cerca con y sin corrección, test de Hirschberg y determinación de la presencia o no de un tortícolis. Resultados: De los 6143 niños examinados 371 (6 por ciento) presentaba algún trastorno en su motilidad ocular. Estrabismos latentes (forias) fueron encontrados en 253 niños (4.11 por ciento). De ellos, 249 casos tenían exoforias y solo 4 presentaron endoforias. Esotropias pudieron observarse en 22 niños (0.35 por ciento). Exotropias se presentaron en 17 de los niños examinados (0.27 por ciento). Se presentaron 8 casos con anisotropía en V e hiperfunción de oblicuos inferiores y 55 pacientes con anisotropía en Y sin disfunción de músculos oblicuos. Dos pacientes presentaron desviación vertical disociada. Presentaron nistagmus sin estrabismo 5 niños y parálisis del IV nervio pudieron observarse en 2 casos

Purpose: The purpose of this paper is to determine the prevalence and different types of ocular motility disorders in a population of school children of the Highlands of Ecuador. Patient and Methods: 6143 children with ages between 4 and 16 where examined in two etnically similar areas of the Highland region of Ecuador. 2775 where females and 3368 males. Every child underwent an opthalmological examination that included: Inspection, evaluation of ocular motility, pupilar reflexes, stereopsis, visual acuity without correction and with correction in all the children wearing glasses, external examination, autorrefractometry and videorrefractometry. Autorrefractometry with cycloplegia and retinal examination were performed in all children with vision levels less than 0.8 in a least one eye, to ocular motility evaluation consisted in assement of the eyes excursion in all 9 positions, of gaze Cover test for distance and near, Hirschber test and determining the presence of an anomalous head posture. Results: Of the 6143 children evaluated, 371 (6 percent) presented with some type of ocular motility disturbance. Of theses, 253 (4.11 percent) where latent strabismus. 249 suffered from exophorias and only 4 had esophoses. There where 8 children with V pattern and overaction of inferior obliques and 55 with Y pattern and no disfuction of oblique muscle.