Comportamiento clínico quirúrgico de la exotropía de gran ángulo / Clinical and surgical behavior of large-angle exotropia

RESUMEN Objetivos: Describir algunas características clínicas de la exotropía de gran ángulo y determinar su resultado quirúrgico. Métodos: Se realizó un estudio descriptivo retrospectivo de 35 pacientes atendidos en el Hospital Oftalmológico "Amistad Cuba-Argelia", en la Wilaya de Ouargla, Argelia, en el período enero 2014 - diciembre 2017. Se analizó el comportamiento de algunas variables relacionadas con la exotropía, como fueron la edad del paciente, el sexo, el color de la piel, las alteraciones oftalmológicas asociadas, el grado de ambliopía, el defecto refractivo asociado, el ángulo de desviación preoperatorio y posoperatorio y el tipo de cirugía realizada. Resultados: Predominó el grupo etario entre 24 y 29 años de edad con el 25,7 por ciento; el 51,4 por ciento representó al sexo femenino; el color de la piel negra fue el más frecuente con 48,6 por ciento; la ptosis palpebral correspondió al 11,4 por ciento de las alteraciones oftalmológicas asociadas y al 68,6 por ciento sin alteraciones; la ambliopía moderada se registró en el 42,9 por ciento de los casos; el defecto refractivo más observado fue el astigmatismo miópico con el 37,1 por ciento; el ángulo de desviación preoperatorio más significativo se encontró en el grupo de 71-80 dioptrías con 37,2 por ciento. A los tres meses de la cirugía el 91,4 por ciento de los pacientes se encontró en ortoforia (± 8 dioptrías) y al año de la cirugía el 94,3 por ciento se mantenía en ortoforia. El retroceso de ambos músculos rectos laterales (10,0 mm) más la resección de un músculo recto medio (7 mm) se realizó en el 37,2 por ciento de los pacientes. Conclusiones: La casi totalidad de los pacientes con exotropía de gran ángulo logran el alineamiento ocular y consiguen una mejoría en la calidad visual(AU)

ABSTRACT Objectives: Describe some clinical characteristics of large-angle exotropia and determine its surgical outcome. Methods: A retrospective descriptive study was conducted of 35 patients attending Cuba-Algeria Friendship Ophthalmological Hospital in the wilayah of Ouargla, Algeria, from January 2014 to December 2017. Analysis was carried out of variables related to exotropia, such as the patients' age, sex, skin color, associated ophthalmological alterations, degree of amblyopia, associated refractive defect, pre- and post-operative angle of deviation, and type of surgery performed. Results: The 24-29 year age group prevailed with 25.7 percent; 51.4 percent of the patients were female; black skin color was the most common with 48.6 percent; eyelid ptosis represented 11.4 percent of the associated ophthalmological alterations and 68.6 percent without alteration; moderate amblyopia was present in 42.9 percent of the cases; the most frequent refractive defect was myopic astigmatism with 37.1 percent; the most significant preoperative angle of deviation was found in the 71-80 diopter group with 37.2 percent. Three months after surgery, 91.4 percent of the patients were orthophoria (± 8 diopters) and at one year 94.3 percent remained orthophoria. Bilateral lateral rectus muscle recession (10.0 mm) plus resection of a medial rectus muscle (7 mm) was achieved in 37.2 percent of the patients. Conclusions: Practically all patients achieved ocular alignment and improved their visual quality(AU)

Comparison of the Outcomes of Two- and Three-muscle Surgery in Exotropia over 45 Prism Diopters

PURPOSE: We report the outcomes of two- or three-muscle surgery on patients with large-angle exotropia exceeding 45 prism diopters (PDs). METHODS: We retrospectively analyzed data on 45 exotropia patients (> 45 PDs) who underwent two- or three-muscle surgery. We excluded patients with paralytic or restrictive strabismus, A- or V-pattern strabismus, a coexistent oblique dysfunction or nystagmus, and/or a history of prior extraocular muscle surgery. Only patients for whom at least 6 months of follow-up data were available were included. Successful surgery was defined as postoperative esotropia ≤ 5 PD, orthophoria, and exotropia ≤ 10 PD at the last visit. RESULTS: We included 45 patients, of whom 22 and 23 underwent two- and three-muscle surgery, respectively. The mean postoperative deviations were 9.5 and 2.7 PD in the two- and three-muscle groups, respectively; the overall success rates were 54.55% (12/22) and 91.30% (21/23). Subgroup analyses revealed that the surgical success rate of two-muscle operations was 66.67% (12/18) in 45–55 PD patients and 0% (0/4) in ≥ 55 PD patients; the success rates of three-muscle operations were 100% (7/7) and 87.50% (14/16). The success rate did not differ significantly between those with postoperative deviations of 45–55 PD (p = 0.137), but did between those who underwent two- and three-muscle operations to treat postoperative deviations of ≥ 55 PD (p = 0.003). CONCLUSIONS: Satisfactory results can be achieved via two-muscle surgery in patients with exotropia 55 PD, three-muscle surgery is superior to two-muscle surgery. Therefore, large-angle exotropia is optimally treated via three-muscle surgery.

Therapeutic evaluation of lateral rectus super-recession surgery for large angle divergence excess exotropia / 中华实验眼科杂志

Background In clinic practice,three or four rectus muscles often are needed to perform operation for the correction of large angle (＞50Δ) exotropia to avoid eye limited abduction due to lateral rectus superrecession.However,recent study reported that lateral rectus super-recession surgery can effectively correct large angle exotropia without remarkable abduction limitation.This outcome still need to be verified in clinical practice.Objective This study was to observe the outcome of bilateral rectus super-recession or medial rectus resection of the combined non-dominant eye for large angle exotropia.Methods A series case study was carried out.Fifty-one patients with intermittent or constant exotropia were enrolled in Tianjin Eye Hospital from May 2013 to October 2014.There were 29 intermittent exotropia and 22 constant exotropia among the 51 patients.Combined with adjustable sutures,bilateral lateral rectus super-recession or medial rectus resection of combined non-dominant eye was performed in all the eyes,and the examination of the anterior segment,fundus,ocular movement and binocular vision were performed before and after surgery.The deviation angle was measured by prism and alternate cover test.The individualized surgery procedure was designed according to medical history,ocular movement,sensory status and deviation angle.The patients were followed-up for at least 6 months.The eye position,ocular movement and binocular sensory function were compared between peoperation and postoperation.This study was approved by the Ethics Committee of Tianjin Eye Hospital.Written informed consents before the operation were obtained from all patient or their parents.Results Thirty-three patients underwent bilateral lateral super-recession and 18 patients underwent bilateral lateral super-recession of the medial rectus resection of the combined non-dominant eye.The mean angle of exotropia for seeing distance of 5 meters was (-70.57 ± 16.46) Δ (from-52 Δ to-120 Δ) and was (-75.65 ±16.14) Δ for seeing near (33 cm) (from-55Δ to-130Δ).The mean amount of left eye recession was 8-15 mm ([11.17±1.67] mm) and the right eye recession was 9-15 mm ([11.28±1.62] mm).The medial rectus of the dominant eye was resected by 3-6 mm.At the end of following-up,the mean angle of exotropia for seeing distance was (-3.45±4.20) Δ (from +4Δ to-14Δ) and was (-5.49±3.96) Δ for seeing near (from +4Δ to-14Δ).Surgical outcome was effective in 41 patients (80.4％),and 10 patients were undercorrected.The stereopsis of 32 patients improved after surgery,and 18 of 27 patients without preoperative stereopsis function obtained stereopsis after surgery.No ocular motility disorder was found in this group of patients after surgery.Conclusions Bilateral lateral rectus super-recesssion or medial rectus resection of combined non-dominant eye can effectively correct large angle exotropia and reduce the number and amount of surgical muscles without ocular motility disorder.

Resultados quirúrgicos a largo plazo en adultos con exotropía de gran ángulo / Long term surgical results achieved in adults with large angle exotropia

Objetivos: determinar el alineamiento quirúrgico en pacientes adultos mayores de 18 años intervenidos quirúrgicamente de exotropía con un ángulo de desviación mayor de 50 dioptrías prismáticas. Métodos: se realizó un estudio descriptivo retrospectivo de septiembre del 2009 a septiembre del 2011, donde se hizo una valoración del alineamiento motor posoperatorio a largo plazo (dos años) a los pacientes con exotropía de gran ángulo que acudieron a la Consulta de Oftalmología Pediátrica y Estrabismo del Instituto Cubano de Oftalmología Ramón Pando Ferrer, a quienes se les realizó cirugía de tres a cuatro músculos en un solo acto quirúrgico. Solo una paciente recibió la cirugía de cuatro músculos horizontales. Resultados: en los 20 pacientes estudiados existió un predominio del sexo femenino. La desviación preoperatoria fue similar de cerca y de lejos; solo un paciente presentó una desviación mayor de 90 dioptrías prismáticas. Se apreció que, al ser evaluados a los dos años, aún 14 pacientes (70 por ciento) se encontraban alineados quirúrgicamente. Conclusiones: se aprecia una gran mejoría de las subescalas psicosocial y funcional posterior a la cirugía, lo cual significa una elevación notable en la calidad de vida de estos pacientes. La casi totalidad de los pacientes logra el alineamiento ocular en un solo tiempo quirúrgico(AU)

Objective: to determine the surgical alignment in adult patients aged over 18 years and operated on from exotropia with deviation angle over 50 dioptries. Methods: a retrospective and descriptive study was conducted from September 2009 through December 2011. It assessed the long-term motor alignment after surgery (2 years) in a group of patients with large angle exotropia, who had been seen at the Pediatric Ophthalmology and Strabismus Service of Ramon Pando Ferrer Cuban Institute of Ophthalmology. Most of them had undergone single-staged three-horizontal muscles squint surgery and just one female patient underwent four-horizontal muscle surgery. Results: females prevailed in the group of 20 patients under study. The preoperative deviation was similar at near and far distances; only one patient presented a deviation bigger than 90 dioptries. It was observed that after two years, 14 (70 percent) of the evaluated patients were surgically aligned. Conclusions: after this surgery, great improvements of the psychosocial and functional subscales were noticed, which leads to remarkable rise of the quality of life in these patients. Almost all of them reached the right ocular alignment in a single-staged surgery.(AU)

Resultados quirúrgicos en adultos con exotropía de gran ángulo / Surgical outcomes achieved in adults with large-angle exotropia

Objetivo: determinar los resultados quirúrgicos en pacientes adultos mayores de 18 años intervenidos quirúrgicamente de exotropía con un ángulo de desviación mayor 50 dioptrías prismáticas. Métodos: se realizó un estudio descriptivo retrospectivo desde septiembre de 2009 a septiembre de 2010, en pacientes (9) que acudieron a la Consulta de Oftalmología pediátrica y estrabismo del Instituto Cubano de Oftalmología Ramón Pando Ferrer y que se les realizó la cirugía de 3 músculos horizontales en un solo acto quirúrgico. Resultados: el mayor grupo se ubicó entre los 18 y 28 años de edad siendo todos en ese intervalo del sexo masculino para un 80 porciento, no existió predominio significativo de un sexo. La desviación preoperatoria fue similar de cerca y de lejos, y se encontró una desviación media de 80 dioptrías prismáticas. De los 5 pacientes que se encontraron hipercorregidos al mes de la cirugía, todos pasaron a la ortotropía al año de la cirugía, solo una paciente quedó hipocorregida desde el inicio la cual está pendiente de otra cirugía para corregir su ángulo residual de 25 dioptrías prismáticas. Conclusiones: se logró una gran mejoría de la subescala psicosocial y funcional después de la cirugía, lo cual significa una elevación notable en la calidad de vida de estos pacientes. Casi todos los pacientes lograron el alineamiento ocular en un solo tiempo quirúrgico y al año de la cirugía todos excepto una paciente se encontraban en ortotropía

Objective: to find out the surgical outcomes achieved in adult patients aged over 18 years, who were operated on from more than 50 D deviation angle exotropia. Methods: a retrospective and descriptive study was conducted from September 2009 through September 2010 in nine patients, who had gone to the pediatric ophthalmology and strabismus service of Ramon Pando Ferrer Cuban Institute of Ophthalmology. They all underwent a single-stage three horizontal muscles squint surgery. Results: the largest group was made up of male patients aged 18 to 28 years for 80 percent; none of both sexes was significantly predominant. The preoperative deviation was similar near and distant, with mean deviation of 80 D. Of the five overcorrected patients one month after surgery, all reached orthotropia a year later, except for one female patient who showed overcorrection from the very beginning and is waiting for another surgery to correct the residual angle of 25 D. Conclusions: after this surgery, great improvement of the psychosocial and functional subscales was attained, which leads to remarkable rise of the quality of life in these patients. Almost all of them reached ocular alignment in just a single surgical time, and one year after surgery, all except one were found orthotropic

Surgical Outcomes of Large-Angle Exotropia

PURPOSE: To examine the surgical results of large-angle exodeviations over 30 prism diopters (PD) and correlation factors influencing surgical outcomes. METHODS: The authors retrospectively examined 63 patients with an exodeviation greater than 30 PD. All patients were examined for at least six months after the operation. Near and far deviation angles, age at operation, operation method, and alignment at postoperative one week, one month, three months and six months were analyzed as factors influencing the surgical outcome. RESULTS: The preoperative deviation was 35 to 40 PD (38.1%) in most cases. Forty-five patients underwent bilateral lateral rectus recession, 16 patients underwent unilateral medial rectus resection and lateral rectus recession, and two patients underwent surgery on three different muscles. Success was defined as sustained alignment from esotropia 10 PD to exotropia 10 PD. The success rate was 79.4% at the first week, 77.8% at one month, 73.0% at three months, and 68.3% at six months postoperatively. In particular, the success rate was significantly lower at six months postoperatively in the group with exotropia greater than 45 PD (36.4%). The patients with esotropia on the first postoperative week showed a significantly high success rate (86.6%); however, neither the age at operation nor the operation method affected the surgical results. CONCLUSIONS: Large-angle exodeviations can be successfully approached with a single operation, with a success rate of 68.3% at six months postoperatively. Esotropia of less than 10 PD at the first postoperative week shows the most ideal surgical results. For patients having exodeviations greater than 45 PD, the success rate will decrease over time. Therefore, surgeons should carefully plan for large-angle exodeviation surgery.

The Accuracy of Estimating Postoperative Deviation in Exotropia With over 40 Prism Diopters

PURPOSE: To assess the accuracy of estimating postoperative deviation in large-angle exotropia over 40 prism diopters (PD). METHODS: A retrospective analysis was performed on 61 exotropia patients with over 40 PD exotropia who had undergone 2-muscle surgery by two surgeons and with at least 6 months follow-up. The accuracy was assessed by analyzing the discrepancy between preoperatively predicted residual deviation and deviation at postoperative 6weeks. Successful surgery was defined as deviation within +/- 10 PD at the last postoperative visit. RESULTS: More accurate residual deviation was predicted in exotropia with prism diopters between 40 and 59 (97.8%) than in exotropia with 60 PD or more (62.5%). And there was no significant difference between two surgeons. Surgical success rates at six months and one year after surgery were 96.8%, 94.7% in exotropia with 40 to 49 PD, 71.4%, 60.0%, 50 to 59 PD, 50.0%, 45.5%, 60 PD or more, respectively. There were four patients of whom the postoperative deviation angle exceeded more than 10 PD of the estimated deviation. CONCLUSIONS: The accuracy of estimating residual deviation prior to surgery was higher and more successful surgery was achieved in exotropia ranging in 40 to 59 PD than in exotropia with 60 PD or more. Therefore, 2- muscle surgery will be suitable for large-angle exotropia with less than 60 PD.

The Surgical Outcome of Partially Accommodative Esotropia with a Large Angle of Deviation

PURPOSE: To investigate the surgical outcome of patients with partially accommodative esotropia with a large angle of deviation. METHODS: Twenty-one patients with partially accommodative esotropia that had angles of deviation of at least 40 prism diopters without correction, were retrospectively studied. They underwent standard surgery, for which the amount of recession was based on the average of the distance and near deviation with correction. The angle of deviation were evaluated at postoperative 3 months and at the last follow-up, and the Titmus test and Worth 4-dot test were performed after surgery. RESULTS: The mean angle of deviation without correction at the first examination was 57.0PD, and the mean age of correction with glasses was 2.6 years. The mean angle of deviation with correction was 31.4PD. The mean age at surgery was 4.4 years. The mean follow-up period was 5.4 years. At 3 months postoperatively, 66.7%, 28.6%, and 4.8% of patients showed acceptable correction, undercorrection, and overcorrection, respectively. At the last visit, undercorrection decreased while overcorrection increased (66.7%, 23.8%, 9.5%). Titmus stereotest showed in positive results with more than 800 seconds of arc in 9 of 16 patients. A Worth 4-dot test resulted in a fusion response at far or at near in 4 of 17 patients. CONCLUSIONS: In partially accommodative esotropia with a large angle of deviation (at least 40PD without correction), the results of conventional surgery were relatively fair, while the prognosis of sensory function was poor.

A Case of Intramuscular Hemangioma Presenting with Large-angle Hypertropia

PURPOSE: To report the case of a patient with large-angle hypertropia of an intramuscular hemangioma of the right superior rectus muscle (SR). METHODS: A 63-year-old man with progressive vertical deviation of the right eye for the past 6 months visited our strabismus department; his condition was not painful. An examination indicated that he had 60PD of right hypertropia at distance and near in primary gaze. Additionally, a significant limitation of his downgaze was noted. The right eye appeared mildly proptotic, and the upper and lower eyelids were slightly edematous. Corrected vision was 20/20 in both eyes. RESULTS: Orbital magnetic resonance imaging (MRI) studies revealed fusiform enlargement of the right superior rectus muscle, with prominent but irregular enhancement following gadolinium administration. Incisional biopsy revealed an intramuscular hemangioma in the superior rectus muscle with cavernous-type vessels. CONCLUSIONS: This case demonstrates that intramuscular hemangioma should be considered in the differential diagnosis of isolated extraocular muscle enlargement and unusual strabismus.

The Clinical Feature and Surgical Outcome of Infantile Exotropia

PURPOSE: To investigate the clinical features and treatment of infantile exotropia which developed in the first year of life. METHODS: The medical records of infantile exotropia operated on in our hospital were reviewed for preoperative and postoperative deviation, cycloplegic refraction, Worth 4-dot test and Titmus stereo acuity test. RESULTS: Preoperative mean deviation was 37 prism diopters. The average post-operative follow-up period was 26.5 months (12~86 months). Twelve patients (71%) had successful horizontal alignment with final horizontal deviations of less than 8 prism diopters, and five patients were undercorrected between 10 and 20 prism diopters. None were overcorrected. Six patients (35%) had fusion at distance and near as well as stereoacuity of 200 seconds of arc or less. Both preoperative and postoperative associated anomalies were inferior oblique muscle overaction (35%), dissociated vertical deviation (18%), both inferior oblique muscle overaction and dissociated vertical deviation (18%), nystagmus (12%) and V-pattern (6%). CONCLUSION: Although infantile exotropia is rare, it has similarities to infantile esotropia. Infantile exotropia features a large-angle deviation, accompanied with inferior oblique muscle overaction and dissociated vertical deviation. After operation, no cases were overcorrected, while high levels of binocular function, and stereoacuity developed in some cases.

Treatment of Exotropia Caused by Lost Medial Rectus Muscle

PURPOSE: We report three patients with large angle exotropia had lost medial rectus muscle (MR) and who attained good alignment postoperatively. METHODS: Patient 1 was a 51-year-old female with a history of strabismus surgery done at 10 years of age. Exotropia of 80 prism diopter (PD) gradually developed with limitation of adduction in the right eye. Patient 2 was a 52-year-old male with fixed exotropia of 95 PD in his left eye, which became blind after a severe contusion injury. The third patient was a 46-year-old male who had MR of the right eye cut during endoscopic sinus surgery. Severe limitation of adduction followed with exotropia of 50 PD. We could not find MR in any of the three patients and noted severe adhesion between eyeball and Tenon's capsule. Ocular movement was severely limited horizontally and even vertically. RESULTS: Postoperatively Patient 1 showed orthophoria in follow-up of 2 years. Patient 2 had 16PD of exotropia in follow-up of 13 months, which was cosmetically acceptable. Patient 3 obtained orthophoria after surgery and developed 10 degrees of left head turning to avoid diplopia. CONCLUSIONS: When a patient shows longstanding large angle exotropia with limitation of adduction, we may consider the MR loss. A reasonable treatment may be to align the eyes cosmetically in primary position by weakening the abducting power and suturing the anterior part of nasal Tenon's capsule to the MR insertion site after adhesiolysis.

Effects of Bilateral Lateral Rectus Recession and Unilateral Recession-Resection in Large Angle Exotropia

PURPOSE: To evaluate the effect of bilateral lateral rectus recession and of unilateral rectus recession and resection in the patients who showed large angle exotropia. METHODS: Sixty-five patients who underwent either bilateral lateral rectus recession or unilateral recession-resection and who were followed up for more than 1 year between 1996 to 2001 at Chonnam University Hospital, were reviewed. The effect of bilateral lateral recession and unilateral recession-resection was compared according to preoperative angle of deviation. Successful outcome was defined as esotropia

Effect of Both Lateral Rectus Recession in Large Angle Exotropia

PURPOSE: To evaluate of the effect of both lateral rectus recession according to the amount of the recession in the patients who showed large angle (>or=35 prism diopter, PD) exotropia. METHODS: The 120 patients who underwent both lateral rectus recession and followed up more than 1 year between 1996 to 2002 at Chung-nam university hospital, were reviewed. The effect of both lateral rectus recession was compared according to the amount of recession and preoperative angle of deviation. Successful outcome was defined as esotropia

Effect of Both Medial Rectus Recession in Large Angle Infantile Esotropia

PURPOSE: To evaluate of the effect of bilateral medial rectus recession in the patients who showed large angle (>50 prism diopters, PD) infantile esotropia as comparing small angle (50 PD, 14 patients) and small angle group (

Long-Term Results of Three or Four Horizontal Muscles Surgery in Large Angle Infantile Esotropia

Long-term surgical results for 3 or 4 horizontal muscles surgery were evaluated in 58 infantile esotropes with large angle of 55 PD or more. They were followed up for 2 years or more(mean 5.6+/-2.16 years). The mean preoperative deviation was 63.2(+/-5.30)PD, ranging from 55 to 75 PD. Monocular preference was shown in fifty seven percent(34 patients)at the first visit. Thirty eight patients(65.5%)were aligned within+/-8 PD of orthotropia after primary procedure and forty nine patients(84.5%)after the second operation. The immediate postoperative deviation averaged 4.8+/8.99 PD of exotropia in 38 patients all of whom were aligned within+/-8 PD of orthotropia at the last visit. Prospectively, the patients with immediate overcorrection of 4 to 9 PD of orthotropia after surgery were found to be mostly aligned within 8 PD of orthotropia at the last visit. Among the 49 patients with stereopsis testing, 29 patients(58%)had measurable stereopsis and 70%of these patients had favorable stereopsis of 800 seconds or less. In conclusion, 3 or 4 horizontal muscles surgery was effective as initial procedure in large angle infantile esotropia with 55 PD or more deviation. Small amount of exotropia less than 10 PD in the immediate postoperative period was desirable for the best long-term alignment.

The Surgical Outcome of Bilateral Lateral Rectus Recession in Large Angle Exotropia

To evaluate the results of bilateral recession in large angle exotropia we examined medical records of 73 patients who had exotropia larger than 35PD and underwent bilateral lateral rectus recession. The mean of follow-up period was 16months. Successful alignment, defined as a final alignment of orthophoria, esotropia less than 5PD or exotropia less than 10PD was achieved in 44 patients(60.3%). There were no differences in age, refractive error, preoperative angle of deviation, prevalence of amblyopia, the presence and concurrent correction of vertical or cyclodeviation, the development of diplopia and the duration of follow-up period between the successful alignment group and failure group. The esodeviation on postoperative one-day tended to ensure a more satisfactory result, but it was not statistically significant. There were no statistically significant differences in stereoacuity and postoperative angle of deviation among the different fusional ability groups. The stereoacuity and postoperative angle of deviation did not show a positive correlation. However, on the two separate examinations of the stereoacuity and fusional ability, the latter results showed improvement in both parameters. This result suggests that the correction of exodeviation may play a role in improving binocular visual function in patients with large angle exotropia.

Clinical Analysis of Large Recession of Bimedial Rectus Muscles in Esotropia

Nineteen patients with large angle esotropia who have undergone bimedial rectus recession ranging from 7 to 8 millimeters were evaluated. We retrospectively reviewed preoperative and postoperative visual acuity, deviation, ocular motility, fusion, stereoacuity in all patients. The mean preoperative deviation was 76 prism diopters, ranging from 65 to 95 prism diopters and the mean postoperative follow up interval was 55.6 months, ranging from 26 to 80 months. The overall successful rate(horizontal orthotropia within+/-10 prism diopters) was 42.1%(8/19). The rate of undercorrection was 47.7%(9/19) and the rate of delayed consecutive exotropia was 10.5%(2/19). Fusion at near was found in 36.8%(7/19) and stereopsos of 200 seconds or better was found in 15.8%(3/19) of patients postoperatively.We observed no limitation of adduction or convergence. If reoperation was necessary, there still remain other untouched horizontal muscles on which to operate.Therefore, 7 to 8 millimeter medical rectus recession is the first effective procedure for the correction of large angle esotropia with deviations of more than 65 prism diopters.

Comparison of Surgical Results Between Bilateral Rectus Muscle Recession and Lateral Rectus Muscle Recession and Medial Rectus Muscle Resection in Exotropia Over 40 Prism Diopters

It is the purpose of this study to compare the postoperative results of 168 patients with exotropia of basic and simulated divergence excess type over 40 prism diopters; 86 patients had bilateral rectus muscle recessions and 82 patients underwent lateral rectus muscle recession and medial rectus muscle resection. The patients in the former group had averaged 13.7 years of age and 8.2 months of postoperative follow-up period. Those in the latter group averaged 22.9 years and had been followed up for 7.1 months. The postoperative success rates are as follows: 66.7%(57/86) in the bilateral rectus muscle recession group and 68.1%(58/82) in the lateral rectus muscle recession and medial rectus muscle resection group(P>0.05). And the success rates of those older than 16 years without amblyopia are 60.0%(18/30) in the former group and 75.0%(24/32) in the latter group(P>0.05). The lateral rectus muscle recession and medial rectus muscle resection group showed somewhat higher rates of success even though it proved statistically insignificant.

Recognition and Repair of the Slipped Muscle

Eight consecutive case of the slipped muscle are recognized and treated with the surgical intervention. All patients showed a large-angle exotropia(30 - 70 prism diopter), moderative to severe degree of limitation of adduction(-1.5 - -3) and negative forced duction test. Intraoperatively, we could identify the empty muscle capsule attached to the sclera with the tendon slipped posteriorly within its capsule. Repair is accomplished by resecting the empty capsule and advancing the true tendon to or toward the original insertion. After the average follow up period of 36.1 weeks, the amount of reduced within 10 prism diopters and limitation of duction within-0.5 in all patients. A better understanding of the pathology may lead to early diagnosis and surgical repair, and then the prognosis for functional and cosmetic result will be excellent.