Marginal myotomy of the minimally overacting inferior oblique muscle in asymmetric bilateral superior oblique palsies.

PURPOSE: We report the surgical results of marginal myotomy of a minimally overacting inferior oblique muscle in conjunction with traditional recession or myectomy of the greater overacting inferior oblique muscle in 10 patients with asymmetric bilateral superior oblique palsies and asymmetric inferior oblique overaction. METHODS: Ten consecutive patients with bilateral superior oblique palsies had a hypertropia in primary position (5-28 PD) and unequal inferior oblique overaction (0 to +2 in the lesser overacting inferior oblique muscle, +2 to +4 in the greater overacting inferior oblique muscle). Reversal of the hypertropia was noted in ipsilateral oblique upgaze. All patients underwent a recession or myectomy of the greater overacting inferior oblique muscle and a marginal myotomy of the lesser overacting inferior oblique muscle. RESULTS: Seven patients had no vertical deviation in primary position, 2 patients had a residual hypertropia of 2 to 3 PD, and 1 patient had a residual hypertropia of 8 PD. The abnormal head position present preoperatively in 8 patients was eliminated or greatly improved after surgery. Postoperatively all but 1 inferior oblique overaction was graded as 0 to trace. Mean follow-up time was 19 months (range, 1.5-68 months). CONCLUSIONS: In bilateral superior oblique palsies with asymmetric inferior oblique overaction, a mildly overacting inferior oblique muscle can be corrected by marginal myotomy, combined with a recession or myectomy of the greater overacting inferior oblique muscle. This procedure can reduce or eliminate the hypertropia in primary position while minimizing the possibility of residual inferior oblique overaction.     

Superior oblique myectomy and trochlectomy in recurrent superior oblique myokymia

In patients operated on for superior oblique myokymia with superior oblique tenotomy or tenectomy, symptoms of oscillopsia recur in approximately one-half. Failure of treatment may be caused by incomplete transection of the tendon or by residual attachments and postoperative adhesions between the proximal segment of superior oblique tendon and the globe which allow superior obl6ique muscle contractions to be partially transmitted to the globe. We report a patient with recurrent symptoms of superior oblique myokymia following superior oblique tenectomy who was successfully managed with superior oblique myectomy and trochlectomy via an anterior orbital approach.Dedicated to Dr. G.K. von Noorden on the occasion of his 60th birthday     

两种下斜肌减弱术在先天性上斜肌麻痹治疗中的运用

目的探讨二种下斜肌减弱术在先天性上斜肌麻痹治疗中的效果。方法85例先天性上斜肌麻痹患者,33例垂直眼位<15~Δ行下斜肌部分切除术,52例垂直眼位>15~Δ行下斜肌移位术。结果85例患者中垂直眼位<15~Δ行下斜肌部分切除术者,治愈及好转29人(87.9%),>15~Δ行下斜肌转位术者,治愈及好转41人(78.8%)。术前有代偿头位者均消失或改善。结论先天性上斜肌麻痹垂直眼位<15~Δ可行下斜肌部分切除术,>15~Δ者可行下斜肌移位术。     

Intraoperative traction testing to detect incomplete inferior oblique myotomy/myectomy

PURPOSE: Incomplete transection of the inferior oblique muscle during myotomy or myectomy is an important preventable cause of ineffective inferior oblique weakening surgery. Intraoperative traction testing has been suggested as a means of detecting an incomplete inferior oblique transection. The usefulness of intraoperative traction testing to detect incomplete myotomy was evaluated. METHODS: The subjective "tightness" of the inferior oblique muscle was evaluated after partial and complete myotomy to determine how partial myotomy affected inferior oblique traction testing and to determine whether intraoperative traction testing is an effective means of ensuring that a complete myotomy has been achieved. Serial traction testing was performed on 10 inferior oblique muscles at the time of myotomy and scored, 0+ to 4+ tightness. Testing was performed before myotomy and after 50%, 90%, and total myotomy. RESULTS: In 8 of 10 eyes traction testing remained strongly positive until the inferior oblique muscle had been completely transected. The average inferior oblique muscle tightness of these eight muscles was +1.69 before myotomy and after 50% and 90% myotomy. The tightness decreased to 0 after 100% myotomy. In two cases no inferior oblique muscle could be detected after 50% and 90% myotomy, respectively. These two muscles had preoperative traction testing of +0.5 and +1.00, respectively. CONCLUSIONS: Intraoperative traction testing is a practical and effective method of detecting incomplete inferior oblique myotomy/myectomy, but the test should be interpreted with caution in patients with loose premyotomy muscles.     

Treatment of superior oblique palsy with superior oblique tendon tuck and inferior oblique muscle myectomy

Twelve patients underwent quantitated superior oblique tendon tuck and ipsilateral inferior oblique muscle myectomy in the primary treatment of unilateral superior oblique muscle palsy. Preoperatively, each patient exhibited a vertical deviation of 30-55 prism diopters in at least one position of gaze. Following a single operation, satisfactory ocular alignment was obtained in all but one case, with fusion demonstrable in clinically significant gaze positions. Eight of 12 patients had no measurable vertical deviation in primary position, and two others had residual hyperphorias of only two prism diopters. No tucks were removed for postoperative Brown's syndrome. Superior oblique tendon tuck combined with ipsilateral inferior oblique muscle myectomy appears to be a safe and effective treatment for large angle superior oblique muscle palsy.     

Combined bilateral superior rectus muscle recession and inferior oblique muscle weakening for dissociated vertical deviation.

PURPOSE: Dissociated vertical deviation (DVD) is a common disorder that is often difficult to treat satisfactorily with extraocular muscle surgery. Weakening both elevators in a single eye is uncommonly performed because of possible severe upgaze deficiency or chin-up head posture postoperatively. METHODS: A retrospective review of medical records was performed that yielded 14 patients who had undergone bilateral superior rectus muscle recessions (mean 8.1 mm, range 5-10 mm) and bilateral inferior oblique muscle recession, myectomy, or anterior transposition in the treatment of DVD. Three additional patients with asymmetric inferior oblique muscle overaction or true hypertropia in primary gaze position were identified who had bilateral superior rectus muscle recessions combined with unilateral inferior oblique muscle weakening. RESULTS: Mild-to-moderate elevation deficiencies were common postoperatively but never exceeded -2 up-gaze limitation (scale 0 to -4) except in the immediate postoperative period and were not associated with persistent chin-up head posturing. Cosmetically objectionable upper eyelid retraction occurred in one patient after re-recession of a superior rectus muscle but before inferior oblique muscle surgery. Only three patients undergoing four vertical muscle surgeries had residual DVD >10 PD in primary gaze position, and none exhibited manifest dissociated strabismus warranting further treatment. CONCLUSION: Bilateral superior rectus muscle recession of up to 10 mm combined with inferior oblique muscle weakening appears to be a safe surgical approach in the management of patients with large angle or recurrent DVD. Our data further suggest that simultaneous four vertical muscle surgery may be preferred in some patients to weakening the superior rectus or inferior oblique muscles alone.     

上斜肌麻痹患者斜视矫正术后眼球旋转状态的改变

目的 以眼底照相为客观定量检查方法,探讨单眼上斜肌麻痹患者斜视矫正术后眼球客观旋转状态的改变情况。方法 住院手术的40例（50只眼）单眼上斜肌麻痹的患者分别行患眼下斜肌切断术（15例15只眼）、患眼下斜肌部分切除术（15例15只眼）、患眼下斜肌切断+对侧眼下直肌后退术（10例20只眼）。于手术前和术后1、7、30、90 d行双眼眼底照相检查,使用绘图软件测量黄斑-视乳头夹角,定量记录客观旋转角度。并观察记录垂直斜视角度和眼球运动情况。同时对30例（60只眼）正常人行双眼眼底照相检查,记录眼球客观旋转角度。手术前后比较采用ANOVA即单因素重复测量资料方差分析方法,术后1、7、30、90d分别与术前比较采用平均值之间的多重比较q检验（SNK法）方法,不同术式间比较采用配对t检验方法。结果 30例正常人双眼眼底黄斑-视乳头夹角为右眼6.7°±2.5°,左眼5.9°±2.3°,双眼总和12.6°±4.3°,双眼间差异无统计学意义(t=1.29,P=0.20)。40例单眼上斜肌麻痹患者,术前双眼眼底黄斑-视乳头夹角为患眼14.3°±6.6°,对侧眼12.2°±4.8°,双眼总和26.5°±10.3°-双眼间差异无统计学意义(t=1.64,P=0.11)。上斜肌麻痹患者术前双眼总黄斑-视乳头夹角与正常人比较,差异有统计学意义。手术前后比较,双眼总黄斑-视乳头夹角术前为26.5°±10.3°-术后1、7、30及90d分别为11.7°±4.3°、11.9°±4.9°、13.5°±5.2°、15.9°±3.6°,组间比较差异有统计学意义(F =40.13-P＜0.01)。随术后时间延长眼球客观旋转角度又有逐渐增加的趋势,术后90d与术后1、7d对比差异有统计学意义。下斜肌切断手术组与下斜肌部分切除手术组相比,术眼手术前后黄斑-视乳头夹角改变量的差异无统计学意义(t =0.57,P=0.57)。患眼下斜肌切断+对侧眼下直肌减弱手术组,双眼间对比,手术前后黄斑-视乳头夹角改变量的差异无统计学意义(t=1.78,P=0.09)。结论 单眼上斜肌麻痹患者的眼底为外旋转位,并同时影响麻痹眼和非麻痹眼;减弱下斜肌或下直肌功能均可矫正眼球的外旋转状态,随时间延长,眼球的客观旋转角度有回退的趋势;下斜肌切断和下斜肌部分切除术矫正垂直旋转斜视的效果基本相同。     

Triple partial myotomy of the inferior oblique muscle. Comparison with retropositioning and free myectomy]

In a twelve-year investigation the authors compare the results of three types of weakening operations of the inferior oblique muscle in 298 eyes. The evaluation lead to their views regarding indications of different surgical techniques. In their opinion the best operation is triple partial myotomy of the inferior oblique muscle as it does not influence the horizontal position and preserves the original insertion of the muscle. They modify the techniques of Romer-Apis and Martinez-Oropeza. Fixation of the inferior and external rectus on hooks reveals the surgical field, and the concurrent stretching of the inferior oblique muscle beneath the conjunctiva facilitates its dissection. The authors include triple partial myotomy except for hypertropias in the comprehensive surgical procedure together with plication of the ipsilateral superior oblique muscle in paresis of the trochlear nerve. They indicate retroposition of the inferior oblique muscle only in divergence associated with hyperfunction of the inferior oblique muscle. The operation has a favourable effect on convergent synkinesis and enhances convergence by +2 to +5 degrees. The authors consider free myectomy of the inferior oblique muscle the least physiological operation and use it no longer.     

Inferior oblique weakening surgery on ocular torsion in congenital superior oblique palsy

AIM:To investigate changes in fundus excyclotorsion after inferior oblique myectomy or myotomy.METHODS:The records of 21 patients undergoing strabismus surgery by a single surgeon between 2009 and 2012 were examined. Only patients who had undergone an inferior oblique myectomy or myotomy, with or without horizontal rectus muscle surgery, were evaluated. Digital fundus photographs were obtained, and the angle formed by a horizontal line passing through the optic disc center and a reference line connecting the foveola and optic disc center was measured. Associated clinical factors examined include age at the time of surgery, presence or absence of a head tilt, degree of preoperative vertical deviation, torsional angle, inferior oblique muscle overaction/superior oblique muscle underaction, and surgery laterality. Whether the procedure was performed alone or in combination with a horizontal rectus muscle surgery was also examined.RESULTS:Mean preoperative torsional angle was 12.0±6.4°, which decreased to 6.9±5.7° after surgery (P<0.001, paired t-test). Torsional angle also decreased from 15.1±7.0° to 6.2±4.3° in the myectomy group (P<0.001, paired t-test) but there were no significant changes in the myotomy group (P=0.093, Wilcoxon signed rank test). Multivariable linear regression analysis showed that preoperative torsional angle, degree of inferior oblique overaction, and age at surgery independently and significantly affected postoperative torsional angle.CONCLUSION:Mean torsional angle decreased after inferior oblique myectomy. Degree of preoperative torsional angle, inferior oblique overaction, and age at surgery influence postoperative torsional angle.     

先天性上斜肌麻痹的手术治疗

目的探讨先天性上斜肌麻痹的各种手术方法与疗效及适应症。方法回顾性分析112例先天性上斜肌麻痹患者分别行患眼下斜肌断腱、下斜肌部分切除、下斜肌后徙转位、下斜肌后徙转位联合健眼下直肌后徙术的术后效果。结果术后平均随访22月（7～36月）,下斜肌断腱术22例,术后满意率86.36%,下斜肌部分切除术16例,术后满意率87.5%,两者治疗效果相当,无明显统计学差异;下斜肌后徙转位54例,术后满意率88.89%;下斜肌后徙转位联合健眼下直肌后徙术20例,术后满意率80%。结论先天性上斜肌麻痹患者应根据术前垂直斜视度的大小选用不同的手术治疗方法,且应该早期治疗。下斜肌断腱和下斜肌部分切除术治疗效果相当,适用于矫正垂直斜视度〈15~△者;下斜肌后徙转位适用于矫正垂直斜视度15~△～25~△者;下斜肌后徙转位联合健眼下直肌后徙术适用于矫正垂直斜视度〉25~△者。     

Internal ophthalmoplegia following inferior oblique myectomy: a report of three cases

Three patients are reported in whom paralysis of accommodation and mydriasis (internal ophthalmoplegia) developed following inferior oblique myectomy. In all three patients, accommodation eventually returned to normal; in two, mild anisocoria persisted; in one patient, pupillotonia was noted after 2 1/2 years. The mechanism of this previously unreported surgical complication is thought to be excessive stretching of the nerve to the inferior oblique muscle with secondary trauma to the ciliary ganglion.     

先天性单侧上斜肌麻痹的手术方式分析

目的：探讨先天性单侧上斜肌麻痹的手术治疗方法。

方法：本研究回顾分析对68例先天性单侧上斜肌麻痹患者,根据患眼的下斜肌功能亢进程度和原在位垂直斜度大小选择下斜肌切断并部分切除、下斜肌切断并前转位、下斜肌部分切除联合对侧眼下直肌或同侧眼直肌手术。伴有水平斜视者按水平斜视矫正原则一期或分期手术矫正。

结果：治愈58例,治愈率85.3%,好转7例,好转率10.3%,无效3例,无效率4.4%。

结论：根据下斜肌亢进程度、垂直斜视度及水平斜度选择不同手术方式,通过一期或分期手术,可有效获得较高治愈率。     

Unilateral inferior oblique muscle myectomy and recession in the treatment of inferior oblique muscle overaction: a longitudinal study

BACKGROUND: The comparable long-term outcomes of inferior oblique muscle myectomy and recession for the treatment of superior oblique underaction (in primary position and straight right and left gaze) have not been well documented in the literature. The purpose of this study was to compare longitudinally these two procedures in a similar, patient population with binocular single vision, when both operations were performed by the same surgeon, with a minimum follow-up period of 12 months. METHODS: A total of 24 patients who randomly underwent either a unilateral myectomy (at the temporal border of the inferior rectus muscle) or a standard recession for inferior oblique muscle overaction associated with long-standing superior oblique underaction were evaluated preoperatively at 2 weeks, 4 months, and 12 months postoperatively by the same orthoptist. RESULTS: A total of 23 patients met the study criteria, (12 myectomies and 11 recessions). All but one patient had demonstrable binocular single vision. The average preoperative hyperdeviation in contralateral gaze was 26.5 prism dioptres (Delta) in the myectomies and 20 Delta in the recessions. This was reduced at 12 months postoperatively to 1.75 Delta in the myectomies and to 3 Delta in the recessions. Both procedures were largely self-grading, so that the larger the preoperative hyperdeviation, the greater the effect of surgery. CONCLUSIONS: Single inferior oblique muscle-weakening procedures were effective in the vast majority of patients, even when the preoperative primary position hyperdeviation was 15 Delta or more. An improvement occurred in both groups immediately after surgery and in many throughout the follow-up period represented by a continuing drift towards orthotropia, but there was a recurrence of the hyperdeviation in some of the recession patients.     

不同术式治疗先天性上斜肌麻痹的疗效观察

目的 探讨不同术式治疗先天性上斜肌麻痹的疗效及适应症.方法 本研究回顾分析30例先天性上斜肌麻痹患者手术方式和术后效果.根据下斜肌亢进程度和垂直斜视度数及患眼外旋程度选择不同的手术方式:下斜肌部分切除术、下斜肌前转位术,或联合上直肌或下直肌手术.结果 治愈25例,治愈率83.3%;好转5例,好转率16.7%.结论 根据...     

下斜肌减弱术治疗下斜肌亢进的临床分析

目的探讨下斜肌减弱手术不同方式治疗下斜肌亢进和V征的临床效果。方法下斜肌亢进122例160眼,包括原发下斜肌亢进20例37眼及继发下斜肌亢进102例123眼,采用不同手术方式,对其手术效果进行比较。结果122例中术前82例有代偿头位(67.21%)者,术后82例中代偿头位消失50例,好转28例,无效4例。下斜肌减弱术的手术方式:断腱术6眼;部分切除24眼;后徙80眼;前转位50眼。术前下斜肌亢进程度 1,21眼; 2,91眼; 3,42眼; 4,6眼;术后残留下斜肌 1,3眼;其余均得到矫正。术前V型斜视48例,术后V征消失38例,好转10例。单纯下斜肌减弱矫正原在位垂直斜度≤15△。结论下斜肌部分切除、后徙及前转位术矫正下斜肌亢进及V征同样安全有效。     

先天性上斜肌麻痹手术的临床观察

目的观察先天性上斜肌麻痹手术治疗的临床效果。方法26例(29眼)实施了手术治疗。其中15例(17眼)行下斜肌单纯切断术;合并分离性垂直偏斜3例(4眼)行下斜肌前转位术;垂直斜视度在20△以上者5例(5眼)行下斜肌切断加对侧眼下直肌后徙术;术前没有下斜肌亢进者3例(3眼),行单纯下直肌后徒术。合并内外水平斜视者同时行水平肌的缩短或后徙术。结果治愈22例(25眼),治愈率86.21%(25/29).有效3例(3眼)。其中2例(2眼)行单纯的下斜肌切断,术后残留垂直斜视度6△~10△;1例(1眼)合并DVD者,术中将下斜肌切断并前转位于下直肌旁,术后仍残留有10△的垂直斜视度。无效1例(1眼),合并间歇性外斜视,术前有40△的垂直斜度,术中将下斜肌前移位,同时行内外直肌的手术,术后仍有20△的垂直斜度。患者放弃治疗。结论选择合适的手术方式,早期实施手术,可取得良好的治疗效果。     

Surgical management of V-pattern strabismus and oblique dysfunction in craniofacial dysostosis

INTRODUCTION: Strabismus affects as many as 60% to 70% of patients with craniofacial dysostosis. V-pattern strabismus with severe oblique muscle dysfunction is the most common ocular motility problem seen and can be difficult to manage. Few studies have reported on the results of strabismus surgery in this condition. METHODS: We retrospectively reviewed the surgical management and outcomes of 14 patients with craniofacial dysostosis who underwent 16 operations to determine the optimal surgical procedure and to report on extraocular muscle anomalies noted at the time of surgery. Operations performed included medial rectus muscle infraplacement (n = 2), inferior oblique (IO) recession (n = 3), IO myectomy (n = 3), IO anterior transposition (n = 3), and IO denervation/extirpation (n = 5). RESULTS: All patients had significant residual ocular motility dysfunction postoperatively. No beneficial effect was noted after IO anterior transposition or after medial rectus muscle infraplacement. Modest improvement of the V-pattern and oblique muscle dysfunction was noted after denervation/extirpation and myectomy of the IO muscle. Bilateral absent or anomalous superior oblique tendons were noted in 8 of 9 patients in whom the superior oblique tendon was examined at surgery. CONCLUSIONS: Strabismus in craniofacial dysostosis is complex and difficult to cure with surgery. Denervation/extirpation and myectomy of the IO muscle offered modest benefits, though neither procedure resulted in normalization of ocular motility. Agenesis of the superior oblique tendon may be causally related in a large proportion of affected patients.     

Myectomy versus anterior transposition for inferior oblique overaction

BACKGROUND: Inferior oblique overaction can be either secondary (as a sequela of ipsilateral superior oblique palsy) or primary (commonly associated with horizontal strabismus). Superior oblique underaction often coexists with both primary and secondary inferior oblique overaction. This retrospective case series compares the efficacy of inferior oblique myectomy versus anterior transposition in improving inferior oblique overaction and superior oblique underaction in eyes with either primary or secondary inferior oblique overaction. METHODS: One hundred twenty eyes of 81 patients were included in this retrospective case series, of which 20 had anterior transposition of the inferior oblique and 100 eyes underwent myectomy. Inferior oblique myectomy was compared with inferior oblique anterior transposition in improving inferior oblique overaction and superior oblique underaction in each diagnostic subgroup. Postoperative outcome was qualitatively and quantitatively assessed. Fisher's exact test was used to compare the outcomes. The quantitative improvement of function in terms of inferior oblique overaction and superior oblique underaction was analyzed by regression analysis. RESULTS: When postoperative inferior oblique overaction was considered, there was no statistically significant difference between myectomy and anterior transposition in both primary and secondary inferior oblique overaction. Myectomy was superior to anterior transposition in improving superior oblique underaction in both primary inferior oblique overaction (OR = 0.14; 95% CI, 0.015-1.45; p = 0.056) and secondary inferior oblique overaction (OR = 0; 95% CI, 0-0.027; p < 0.001). The quantitative improvement of function showed a significant difference between procedures for superior oblique underaction (t-test; p = 0.005; 95% CI, 0.25-1.3) but not inferior oblique overaction (t-test; p = 0.8; 95% CI, -0.67-0.54). CONCLUSIONS: This study demonstrates both inferior oblique myectomy and inferior oblique anterior transposition to be effective in correcting primary and secondary inferior oblique overaction. Myectomy is more effective in improving superior oblique underaction associated with both primary and secondary inferior oblique overaction. On this basis, we feel that inferior oblique myectomy has some advantage over anterior transposition in treating combined inferior oblique overaction and superior oblique underaction and can be considered the procedure of choice.     

Book Review

Abstract

Ocular neuromyotonia (ONM) is a rare but distinctive clinical entity characterized by involuntary episodic contraction of one or more muscles supplied by the ocular motor nerves. A retrospective review was conducted on all patients with ONM seen by the neuroophthalmology service in the past 20 years. Ten patients were identified with ONM; six affecting vertical muscles (superior oblique; inferior rectus; superior rectus) and four affecting lateral rectus muscles. Case 1 has been reported previously. Most episodes occurred every 10–40?min, lasted a few seconds to several minutes, and were repeated throughout the day. Only two patients had previously undergone cranial radiation. Two had thyroid eye disease. One patient presented with superior oblique myokymia and subsequently developed ONM. Membrane stabilizing medications were prescribed in 7 of the 10 patients with varied success. ONM episodes ceased after extraocular muscle surgery in one patient with thyroid eye disease.     

Apparent contralateral inferior oblique muscle overaction after unilateral inferior oblique muscle weakening procedures.

BACKGROUND: Unilateral inferior oblique muscle weakening surgical procedures often lead to the appearance of inferior oblique muscle overaction in the contralateral eye. The purpose of this study was to determine how different types of unilateral inferior oblique muscle procedures affect the apparent function of the inferior oblique muscle in the contralateral eye. METHODS: A computer search was performed to locate all patients on the pediatric ophthalmology service at the Wilmer Ophthalmological Institute who underwent a unilateral inferior oblique muscle weakening procedure from 1980 to 1994. Only patients with a diagnosis of primary inferior oblique muscle overaction were included in the study. RESULTS: Fourteen patients met the inclusion criteria. One patient had undergone an anterior transposition of the inferior oblique muscle, seven patients had undergone a 10 mm recession of the inferior oblique muscle, and six patients had undergone a myectomy of the inferior oblique muscle. Before the operation,there was no difference in the inferior oblique muscle function of the contralateral eye among the three groups. However, after the operation apparent inferior oblique muscle overaction developed more frequently and to a greater degree in the contralateral eye among patients in the anterior transposition and 10 mm recession groups than among patients in the myectomy group. CONCLUSION: Either anterior transposition or 10 mm recession of the inferior oblique muscle may limit elevation in abduction in the eye on which inferior oblique muscle surgery was performed. The limitation of elevation in abduction may create apparent inferior oblique muscle overaction in the contralateral eye.