Inferior oblique belly transposition in the treatment of mild inferior oblique overaction with small angle vertical strabismus / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To observe the effect of inferior oblique belly transposition(IOBT)in unilateral mild inferior oblique overaction with small angle vertical stabismus.<p>METHODS: The data of patients who underwent IOBT in our hospital from September 2019 to August 2021 were analyzed retrospectively. Inclusion criteria targeted patients with mild inferior oblique overaction(2+ and below)and small angle incomitant vertical strabismus(4-9PD). The horizontal deviation and vertical deviation in both primary and lateral gazes were measured, and the degree of inferior oblique overaction and fovea-disc angle(FDA)were also evaluated preoperatively and postoperatively.<p>RESULTS: A total of 16 cases(16 eyes)were included, aged 4-39 years. One case was 5a postoperative congenital esotropia with secondary unilateral inferior oblique overaction by mild superior oblique palsy, whereas 15 patients had monocular primary inferior oblique overaction with horizontal strabismus. The follow-up was 3-6mo. The mean improvement of inferior oblique overaction was 2.00(1.25, 2.00)grade from +2.00(2.00, 2.00)preoperatively to 0.00(0.00, 0.00)postoperatively, the difference was statistically significant(<i>Z</i>=-3.70, <i>P</i><0.001). The horizontal strabismus decreased from 69.13±25.86PD preoperatively to 2.75±2.59PD postoperatively(<i>t</i>= 9.929, <i>P</i><0.001). The vertical strabismus in the primary position decreased from preoperative 7.44±1.32PD to 1.00±1.21PD postoperatively(<i>t</i>=22.335, <i>P</i><0.001), mean corrected hypertropia 6.44±1.15PD, and vertical strabismus in lateral gazes decreased from preoperative 12.44±2.73PD to 3.00±2.13PD postoperatively, mean corrected hypertropia 9.44±2.73PD, these differences were statistically significant(<i>t</i>=13.819, <i>P</i><0.001). The FDA decreased from -8.85°±6.53° preoperatively to -6.49°±7.01° postoperatively, the difference was statistically significant(<i>t</i>=-2.384, <i>P</i><0.001), with a mean reduction of 2.36°. No postoperative complications such as postoperative overcorrection or inferior oblique underaction were observed.<p>CONCLUSION:IOBT is safe and effective in correcting unilateral mild inferior oblique overaction with small angle vertical strabismus.

Resection and Transposition of the Inferior Oblique for Hypertropia due to the Inferior Rectus Loss

PURPOSE: To report a case of resection and transposition of the inferior oblique muscle combined with superior rectus recession as treatment for large-angle hypertropia due to unilateral loss of the inferior rectus muscle. CASE SUMMARY: A 39-year-old man presented with a complaint of left hypertropia and vertical diplopia caused by blunt trauma 20 years previously. Left hypertropia of 70 prism diopters (PD) and exotropia of 16 PD in the primary gaze were noted; ocular movements of the left eye showed overactive supraduction (+4) and underactive infraduction (−5). On surgical exploration, neither the inferior rectus muscle nor capsule were present at the insertion site. The patient was diagnosed with loss of the inferior rectus muscle, thus, 7 mm of the inferior oblique muscle was resected and transposed at the original insertion site of the inferior rectus muscle; the superior rectus muscle was then recessed by 4.5 mm. After the surgery, vertical alignment was straight in the primary position, infraduction limitation was changed from −5 preoperative to −2 postoperative, and supraduction was changed from +4 preoperative to −2 postoperative. CONCLUSIONS: Extensive resection and transposition of the inferior oblique muscle combined with recession of the superior rectus may help in obtaining a successful surgical outcome in patients with inferior rectus muscle loss with a large angle of vertical deviation.

Surgical Management of Superior Oblique Muscle Palsy in Hypertropia 16 Prism Diopters or More

PURPOSE: Isolated inferior oblique weakening procedure is an effective treatment for patients with superior oblique muscle palsy who had up to 15 prism diopters (PD) of vertical deviation in the primary position, but 2-muscle surgery is needed for patients with larger deviations. Herein, we report the surgical results of simultaneous 2-extraocular muscle surgery for large primary position hypertropia 16 PD or more caused by superior oblique palsy. METHODS: This study was a retrospective review of the records of patients who presented with central gaze hypertropia 16 PD or more and underwent simultaneous 2-extraocular muscle surgery between January 2003 and June 2014 in Severance Hospital. The patients were divided into 3 groups: 43 patients who underwent inferior oblique (IO) myectomy and contralateral inferior rectus (IR) recession (Group 1), 10 patients who underwent IO myectomy and superior rectus (SR) recession (Group 2), and 8 patients who underwent SR recession and contralateral IR recession (Group 3). Criteria for success included correction of head posture and a primary position alignment within 5 PD of vertical deviation. RESULTS: Mean preoperative alignment at primary gaze was 25.5 ± 7.1 PD (range, 16-60 PD) compared to the postoperative value of -1.3 ± 6.8 PD (range, -20~25 PD) (p < 0.001). Surgery was successful in 49 (80%) patients. Nine (15%) patients were overcorrected and the other 3 (5%) patients were undercorrected. Success rate was the highest in subjects who underwent IO myectomy and contralateral IR recession. Among the 24 patients who did not receive combined horizontal muscle surgery, horizontal deviations decreased from 10.4 ± 2.7 PD to 1.5 ± 5.5 PD (p < 0.001) CONCLUSIONS: Two-muscle surgery can be effective in patients with large hypertropia 16 PD or more. Additionally, horizontal deviations are more likely to be resolved with vertical muscle surgery alone. However, IO myectomy combined with ipsilateral SR recession can cause overcorrection postoperatively, so surgical dose should be reduced when performing weakening procedure of two elevators in one eye.

Correction of Hypertropia Coexisting with Intermittent Exotropia

PURPOSE: To investigate the clinical features associated with hypertropia and report the surgical outcomes of hypertropia coexisting with exotropia. METHODS: We reviewed the medical records of 148 patients with intermittent exotropia coexisting with hypertropia over 4 PD who received exotropia surgery. The cases accompanied by apparent paralytic strabismus such as superior oblique palsy were excluded. Patients were divided into group I(clinically diagnosed hypertropia) and group II (non-specific hypertropia) and the clinical features of coexisting hypertropia and surgical outcomes were analyzed. RESULTS: Among the 148 patients, group Iconsisted of 38 patients (26%) and group II of 110 patients (74%). The average amount of preoperative hypertropia angle in primary gaze was 9.58 +/- 3.89 PD and 6.62 +/- 2.69 PD in group I and II, respectively. Group I included 12 patients with dissociated vertical deviation (DVD), 10 patients with unilateral inferior oblique overaction, 13 patients with asymmetric bilateral inferior oblique overaction and 3 patients with superior oblique overaction. Group II included 19 patients with comitant hypertropia (17%), head tilt positive pattern (simulated superior oblique palsy) was found in 84 patients (76.3%) and variable incomitance was observed. In group I, 29 patients received simultaneous horizontal muscle with hypertropia surgery. Postoperative hypertropia angle in group I was 1.41 +/- 2.93 PD and 4 cases were considered surgical failure. In group II, hypertropia was resolved with horizontal muscle surgery only and the amount of postoperative hypertropia was 0.45 +/- 1.60 PD. CONCLUSIONS: In this study, vertical deviations in intermittent exotropia with concomitant hypertropia related to obvious oblique muscle dysfunction or DVD were corrected effectively by oblique or vertical rectus muscle surgery. Nonspecific hypertropia can be resolved after horizontal muscle surgery alone, however, for precise differential diagnosis, careful examination for variable clinical features is necessary before determining surgery.

Surgical Outcome of Vertical Rectus Muscle Recession in Hypertropia

PURPOSE: To determine the extent of vertical rectus muscle correction in hypertropia showing good prognosis. METHODS: A retrospective study was performed with a total of 16 patients who underwent superior or inferior rectus muscle recession surgery with a follow-up of more than 6 months. Vertical muscle recession of 1 mm per 2.5 to 3.0 prism diopters was performed according to the surgeon's discretion. RESULTS: At 1 week after surgical correction, undercorrection, orthophoria, and overcorrection was observed in 4, 7 and 5 cases, respectively. At the final examination, ocular deviation was decreased in the undercorrected cases and maintained orthophoric except in 1 case where only a small amount of deviation recurred. However, in the cases of postoperative overcorrectionn, ocular deviation increased; 2 cases required surgical correction for consecutive hypertropia. CONCLUSIONS: When performing vertical rectus muscle recession in primary hypertropia, the amount of correction for orthophoria or undercorrection should be determined.

Analysis of Effect of Inferior Oblique Myectomy in Patients With Inferior Oblique Overaction

PURPOSE: To investigate the effect of inferior oblique (IO) myectomy by analyzing the correlation of the amount of inferior oblique overaction (IOOA), hypertropia and excyclotorsion before, between, and after IO myectomy in patients with various degrees of IOOA. METHODS: A total of 86 eyes from 59 patients with IOOA who underwent IO myectomy were enrolled in the present study. The correlation analysis was performed for the amount of IOOA, hypertropia and excyclotorsion before and after surgery, according to the preoperative amount of IOOA, hypertropia, and excyclotorsion. RESULTS: The IOOA decreased from +2.5 +/- 0.6 before surgery to -0.01 +/- 0.25 (p < 0.05) after surgery. The vertical deviation was 5.7 +/- 6.3 prism diopter (PD) and 2.3 +/- 5.2 PD (p < 0.05) postoperatively. The amount of cyclodeviation was 15.3 +/- 7.6degrees before surgery and 6.6 +/- 5.7degrees (p < 0.05) after surgery. The amount of surgical correction for IOOA and the hypertropia was significantly correlated with preoperative deviation (p < 0.05, p < 0.05). The amount of excyclotorsion before and after surgery was also positively correlated but was not statistically significant (p = 0.05). CONCLUSIONS: IO myectomy can correct any degree of IOOA, hypertropia, and related excyclotorsion.

The Relationship of Hypertropia, Inferior Oblique Overaction and Extorsion in Congenital Superior Oblique Palsy

PURPOSE: To evaluate the correlation among hypertropia, inferior oblique overaction (IOOA), and extorsion. METHODS: Thirty-one patients with congenital unilateral superior oblique palsy were evaluated. Visual acuity tests, refraction tests, ocular movement tests, prism cover tests, and fundus photography were performed. The correlations of vertical deviation, IOOA, and extorsion were analyzed. The operation method involved weakening the inferior oblique muscle, and then a comparison was made between measurements 1 month preoperative and 1 month postoperative for vertical deviation, inferior oblique overaction, and extorsion. RESULTS: On average, preoperative hypertropia was 8.84+/-6.88 prism diopters (PD), IOOA was 2.20+/-0.69, and extorsion was 18.06+/-5.83 degrees. The Pearson's correlation of IOOA and extorsion, hypertropia and IOOA, and extorsion and hypertropia were r=0.620, r=0.327, and r=0.126, respectively. Postoperative hypertropia, IOOA, and extorsion were reduced to 1.42+/-3.11PD, 0.42+/-1.11, and 8.63+/-5.09, respectively. CONCLUSIONS: Both extorsion and hypertropia showed significant positive correlations with IOOA, whereas hypertropia and extorsion revealed somewhat weaker positive correlations in congenital monocular superior oblique palsy. In addition, the amount of hypertropia was reduced, and extorsion and IOOA improved after recession of the inferior oblique muscle.

The Effect of Myectomy on the Grading of Overaction of the Inferior Oblique Muscle

PURPOSE: This study assesses the surgical results of inferior oblique myectomy on the degree of overaction in patients with overaction greater than +2 of the inferior oblique muscle. METHODS: Seventy eyes of 54 patients underwent an inferior oblique myectomy and at least 6 months of follow-up. Patients with contracture of the superior rectus muscle or dissociated vertical deviation were excluded. The chief complaints, preoperative and postoperative degrees of overaction of the inferior oblique muscle, the angle of hypertropia, and head tilt were analyzed. RESULTS: Deviation of the eyeball (38.9%) and head tilt (25.9%) were the most common complaints. Overall, the success rate was 91.4%, and the likelihood of success decreased with increasing severity of overaction of the inferior oblique muscle. The angle of hypertropia reduced from 11.9 (Prism diopters, PD) preoperatively to 2.2PD postoperatively (p=0.000). Preoperative head tilting was seen in 20 patients (37%) and all saw postoperative improvement. CONCLUSIONS: Inferior oblique myectomy is effective in treating the overaction of the inferior oblique muscle without contracture of the superior rectus muscle or dissociated vertical deviation, especially in patients with greater than +2 overaction of the inferior oblique muscle.

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.

Acquired Simulated Brown Syndrome following Surgical Repair of Medial Orbital Wall Fracture

Simulated Brown syndrome is a term applied to a myriad of disorders that cause a Brown syndrome-like motility. We encountered a case of acquired simulated Brown syndrome in a 41-year-old man following surgical repair of fractures of both medial orbital walls. He suffered from diplopia in primary gaze, associated with hypotropia of the affected eye. We performed an ipsilateral recession of the left inferior rectus muscle as a single-stage intraoperative adjustment procedure under topical anesthesia, rather than the direct approach to the superior oblique tendon. Postoperatively, the patient was asymptomatic in all diagnostic gaze positions.

The Surgical Correction of Vertical Deviation after Superior Rectus Muscle Recession in Patients with Hypertropia

PURPOSE: In general, the amount of vertical rectus surgery is based on achieving 3 prism diopters (PD) of realignment for each millimeter of muscle recession. The study aimed to determine the surgical correction of vertical deviation in patients with hypertropia after superior rectus muscle recession. METHODS: A total of 32 patients with hypertropia underwent 2-8 mm recession of the superior rectus muscle. The average surgical correction for each millimeter of recession was calculated by deducting the post-surgical deviation from the pre-surgical vertical deviation and dividing the remnant by the amount of recession (mm). RESULTS: The average surgical correction was 2.2 +/- 0.7 PD for each millimeter of superior rectus recession. There was no statistical significance in the change in surgical correction in terms of follow-up period, which was categorized as one day, one, two, and six months, and one year (P>0.05). The relationship between surgical correction and age (below and above 11 years old), gender or the amount of recession (below or above 5 mm) was not statistically significant (P>0.05). There was no statistically significant difference in vertical correction between esodeviation and exodeviation (P>0.05). CONCLUSIONS: The study showed an average surgical correction of vertical deviation of 2.2 PD for each millimeter of superior rectus muscle recession. The results suggest that increased recession, within the maximum limit of 8 mm, is an effective approach to prevent undercorrection for children who have hypertropia but cannot undergo adjustable strabismus surgery.

Graded Partial Tenotomy of Vertical Rectus Muscles for Treatment of Hypertropia

PURPOSE: To evaluate the effectiveness of graded (adjustable intraoperatively) partial vertical rectus muscle tenotomy at the insertion in correcting small degrees of hypertropia. METHODS: All patients with best corrected visual acuity of better than 6/30 in both eyes who had undergone only partial tenotomy of vertical rectus muscle(s) over a 30-month period were included. Improvement was evaluated 6 weeks postoperatively as the change in alignment in prism diopters (PD) in primary gaze and in the field of action of the affected rectus muscle(s). Binocular function was evaluated by Titmus stereoacuity and the Worth 4-light tests. RESULTS: All 24 patients who met the inclusion criteria had diplopia preoperatively, and this had resolved in 17 (71%) postoperatively (P<0.005). Prisms were used by 6 preoperatively vs. 2 postoperatively (P<0.05). The average vertical deviation in primary gaze decreased from 8 PD to 2 PD (P<0.005). In the field of action of the treated rectus muscle, hypertropia decreased from an average of 8 PD to 3 PD (P<0.005). For the available pre- and post-operative assessments, stereoacuity improved after 10 of the 18 (56%) procedures and Worth 4-light testing showed improvement or maintenance of fusion after 13 of 19 procedures (68%). CONCLUSIONS: Graded vertical rectus partial tenotomy can effectively reduce small degrees of hypertropia and associated diplopia, improve binocular function, and reduce or eliminate the need for prism correction.

Anterior Transposition of Inferior Oblique Muscle for Treatment of Unilateral Superior Oblique Muscle Palsy with Inferior Oblique Muscle Overaction

Although many weakening procedures for the inferior oblique muscle have been advocated, there is some controversy as to the most beneficial procedure for weakening overacting inferior oblique muscles. This study was undertaken to determine if unilateral anterior transposition of the inferior oblique muscle alone could be a safe and effective procedure for treating unilateral superior oblique palsy from the perspective of hypertropia, inferior oblique overaction, and abnormal head posture. The records of 33 patients, who underwent anterior transposition of the inferior oblique muscle for unilateral superior oblique palsy at our institution between Jan 1995 and Dec 2002, were retrospectively reviewed. The average preoperative inferior oblique overaction was 2.3 +/-0.64, and the hypertropia in the primary position was 12.3 +/-7.69 prism diopter (PD). Twenty-six patients showed head tilt to the opposite direction preoperatively. After the anterior transposition of the inferior oblique, inferior oblique overaction was diminished in 32 patients (97%). Twenty-six out of 33 patients (79%) had no hypertropia in the primary position at last postoperative assessment. Of the 26 patients with head tilt before surgery, 21 patients (81%) achieved full correction after surgery. Satisfactory results were obtained in most of the patients in our study with the exception of three patients who required additional surgery. No patient demonstrated postoperative hypotropia in the primary position. None of the patients noticed elevation deficiency or lower lid elevation. The anterior transposition of the inferior oblique was found to be safe and effective for treating superior oblique palsy with secondary overaction of the inferior oblique muscle.

The Effect of Modified Anterior Transposition of the Inferior Oblique Muscle for Hypertropia in Superior Oblique Muscle Palsy with Inferior Oblique Muscle Overaction

PURPOSE: The authers studied the effect of modified anterior transposition of the inferior oblique muscle for hypertropia in superior oblique muscle palsy combined inferior oblique muscle overaction. METHODS: We retrospectively analysed 19 cases of superor oblique palsy, which were treated by modified inferior oblique muscle anterior transposition from January 1999 to march 2001. Mean follow-up was 14.6 months. The medial portion of inferior oblique muscle was transpositioned to 1mm posterior position of the temporal insertion of inferior rectus muscle and lateral portion of inferior oblique muscle was moved 5mm on imaginary line, which is the line of between temporal insertion of inferior rectus and inferior insertion of lareral rectus muscle, to the direction of inferior insertion of lateral rectus muscle from temporal insertion of inferior rectus muscle, then backward 6mm from that point perpendicularly. RESULTS: The success rates in modified anterior transposition were 94% in under 20delta of hypertropia and 89.5% in over +3 of IOOA. CONCLUSIONS: Modified anterior transposition is an effective procedure of +3 to +4 inferior oblique muscle overaction and hypertropia in superior oblique muscle palsy as a primary surgery.

Concomitant Hypertropia with Intermittent Exotropia

PURPOSE: To investigate the incidence and characteristics of vertical deviation in the intermittent exotropia. METHODS: Fifty consecutive intermittent exotropes over age of 5 were prospectively studied. Patients with any significant ocular and neurologic abnormalities or orbital anatomic abnormalities, definite oblique dysfunction with A or V pattern were excluded. Ophthalmologic evaluation included visual acuity, ocular movements, measurements of angle of deviation by prism cover test, Bielschowsky head tilt test, stereoacuity test, and fundus observation for torsion by indirect ophthalmoscopy. RESULTS: We found that 27 children(54%) had concomitant hypertropia in primary position. Mean amount of hypertropia was 4.81 PD(range: 2~20 PD). Thirty nine children(78%) showed positive Bielschowsky head tilt test. No objective torsion was observed. No inferior oblique overaction was found except for only 2 patients. All subjects had good visual acuity and stereopsis. CONCLUSIONS: The incidence of vertical deviation in the intermittent exotropia is much higher than expected. All of the vertical deviations show positive Bielschowsky head tilt test.

Anterior Transposition of the Inferior Oblique Muscle for Treatment of Hypertropia in Superior Oblique Muscle Palsy

Anterior transposition is one of the most commonly used inferior oblique weakening procedures. It has been known to be effective in the case of dissociated vertical deviation with inferior oblique overaction or hypertropia due to superior oblique palsy.this study was undertaken to determine whether anterior transposition is effective in the correction of vertical deviation and head tilt in 19 patients with hypertropia due to superior oblique palsy. Preoperative average scale of inferior oblique overaction was +2.4+/-0.7mm, and the elimination of overaction was noted in 14 patients(74%). Preoperative prism-cover for hypertropia in primary position averaged 12.7+/-6.2, and the mean reduction of hypertropia in primary position was about 10. Head tilt was uniformly eliminated in 9 of 12 patients(75%). Therefore, we can expect the reduction of hypertropia about 10 and the elimination of head tilt, using only anterior transposition in hypertropia and inferior oblique overaction due to superior oblique palsy, especially when the amount of vertical deviation is within 13.

Surgical Correction of Exotropia due to Oculomotor Nerve Palsy

In third nerve palsy, the functions in the four of the six extraocular muscles are compromised and its treatment is the most difficult problem in the paralytic strabismus. In surgical method, large recession and resection of horizontal rectus muscles, lateral rectus muscle transposition to medial rectus muscle and superior oblique muscle transposition are used for strabismus surgery on oculomotor nerve palsied eye. We compared the results of two methods of surgical correction. In three eyes, lateral muscle transpositions to medial rectus muscle were performed. On the last follow up examination (men; 6.7 months), two eyes resulted in severe hypertropia and unacceptable ocular alignment and no improvement of limited adduction. In six eyes of whom superior oblique muscle transpositions were performed, all resulted in acceptable ocular alignment, no hypertropia, and the limitations of adduction were improved markedly. Therefore, in the treatment of third nerve palsy, sperior oblique muscle transposition is more effective than lareral rectus muscle transposition to medial rectus muscle.