A case report of inferior oblique reattachment after Inferomedial Orbital Wall Reconstruction from Total Maxillectom

@#The detachment and reattachment of inferior oblique (IO) have been done by ophthalmologists in inferomedial orbital wall fracture repair to avoid inducing a new diplopia in patients post-operatively. However, doing them in orbital wall reconstruction in patient who underwent maxillectomy for a malignancy has not been described yet. We describe a case where a disinserted inferior oblique was reattached after titanium mesh implantation to prevent diplopia after the surgery. This is the case of a 40-year-old male diagnosed with recurrent bilateral nasomaxillary ameloblastoma who underwent total maxillectomy of the right with removal of the inferomedial orbital wall, and detachment and reattachment of inferior oblique with no resulting inferior oblique palsy and diplopia from hypotropia or incyclotorsion. This is the first report, to our knowledge, to describe reattachment of IO in its approximate insertion during reconstruction of the inferomedial orbital wall after total maxillectomy from a malignancy with no resulting diplopia.

Parálisis aislada del músculo oblicuo inferior izquierdo / Isolated Left Inferior Oblique Muscle Palsy

La parálisis aislada del músculo oblicuo inferior constituye la parálisis menos frecuente de todas las que afectan a los músculos extraoculares. Se realiza la presentación de una paciente de seis años de edad con antecedentes de salud que fue traída por su madre a la consulta de oftalmología pediátrica y estrabismo por presentar una desviación ocular desde los primeros meses de nacida. Se planteó como posibles diagnósticos un síndrome de Brown del ojo izquierdo o una parálisis del músculo oblicuo inferior izquierdo, se confirmó el segundo diagnóstico con el test de ducción forzada. Existen varias opciones quirúrgicas para estos pacientes. El objetivo fue determinar si se logra el alineamiento quirúrgico en la posición primaria de mirada con la intervención quirúrgica propuesta de recesión del recto superior derecho 5 mm. La paciente se encuentra alineada en posición primaria de mirada, sin limitación de las versiones y sin tortícoli(AU)

Isolated palsy of the inferior oblique muscle is the least frequent of all palsies affecting the extraocular muscles. We present a six-year-old female patient with a medical history who was brought by her mother to the pediatric ophthalmology and strabismus clinic because she presented an ocular deviation since the first months of her life. A Brown's syndrome of the left eye or left inferior oblique muscle palsy was proposed as possible diagnoses, the second diagnosis was confirmed with the forced duction test. There are several surgical options for these patients. The objective was to determine if surgical alignment in the primary gaze position is achieved with the proposed surgical intervention of right superior rectus recession 5 mm. The patient is aligned in the primary gaze position, without limitation of the versions and without torticollis(AU)

Occurrence and subsequent development of vertical deviations in patients treated surgically for infantile esotropia

Purpose: The purpose of this study was to evaluate the onset of dissociated vertical deviation (DVD) and inferior oblique overaction (IOOA), their subsequent development, and their correlation with pre and postoperative parameters. Methods: Medical records of patients with infantile esotropia who underwent surgery between 2005 and 2017 were retrospectively reviewed. DVD and IOOA were measured before and after surgery. Patients were divided into two groups based on horizontal and vertical deviation at the time of presentation: those with infantile esotropia only (group A) and patients with infantile esotropia who developed vertical deviation (group B). Results: Out of a total of 102 patients, DVD occurrence was seen in 53 patients (51.9%) and IOOA was seen in 50 patients (48.04%). DVD was seen in 22 patients at the time of initial examination and in 31 patients postoperatively. IOOA at presentation was seen in 45 patients (44.1%) and 5 patients (8.8%) postoperatively. No statistical difference was found in the age of surgery, angle of deviation, mean follow?up, and mean refractive error within both groups. The postoperative motor outcome was statistically comparable between the two groups (P = 0.29). Sensory outcomes of fusion (P = 0.048) and stereopsis (P?value = 0.00063) were better in group A. Conclusion: No correlation was found between the age of occurrence and development of vertical deviation with refractive error, angle of deviation, age, or type of surgery. We found that motor outcomes are not affected but sensory outcomes are affected in patients with vertical deviations. This indicates that DVD and IOOA are developed due to inherent disruption of fusion and stereopsis

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.

Surgical management of Helveston syndrome (triad of A- pattern exotropia, superior oblique overaction and dissociated vertical deviation) using 'Four Oblique' procedure

Purpose: To report the surgical outcomes in six patients of Helveston syndrome using a 揻our oblique� procedure. The popular methods for surgical management include superior rectus recessions alone or combined with superior oblique tenectomy. However, large angle exotropia correction would entail a higher risk of anterior segment ischemia when the superior rectus needs to be operated along with the horizontal recti. Hence, we evaluated the long-term results of this uncommon procedure. Methods: This was a retrospective review of six patients diagnosed to have manifest dissociated vertical deviation (DVD) with A pattern exotropia with bilateral superior oblique over action. All patients underwent horizontal muscle recessions/resections for exotropia along with bilateral posterior tenectomy of the superior oblique with inferior oblique anterior transpositioning. Results: The median age was 10 years (Range 5� years). The mean postoperative follow-up was 26 � 14.02 months (Range 12� months). The mean reduction in exotropia was from 36.5 � 21.06 PD (Range 15� PD) to 6.1 � 3.06 PD (Range 3� PD). The procedure corrected the A pattern from a mean 23 � 7 PD (Range 15� PD) to 7.6 � 3.2 PD (Range 3� PD). The average DVD in the right eye reduced from 14 � 4.3 PD (Range 8� PD) to 5.3 � 1.2 PD and in the left eye from 14.33 � 3.6 PD (Range 10� PD) to 4.1 � 1.1 PD. The DVD asymmetry reduced from 6.33 � 3.4 PD to 1.5 � 1.3 PD. Conclusion:擣our oblique� procedure with horizontal muscle surgery seems to be an effective method for significantly correcting the A pattern as well as reducing the DVD with good long-term outcome in our case series.

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.

Anterior transposition of inferior oblique muscle with unequal excision for segregated vertical strabismus with asymmetric inferior oblique hyperfunction / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To explore the application of anterior transposition of inferior oblique muscle with unequal excision in treatment of segregated vertical strabismus with asymmetric inferior oblique hyperfunction.<p>METHODS: A total of 22 patients(10 males and 12 females, 28 eyes in all)who underwent anterior transposition of the unequal excisional inferior oblique muscle for dissociated vertical deviation with asymmetric inferior oblique muscle overaction were studied retrospectively. The patients were admitted from June 2015 to June 2017,with mean age at 12.32±6.81 years old(ranging from 3 to 28 years old). The binocular vision, the curative effect of DVD, the curative effect of inferior oblique muscle overaction, eye position and compensatory head posture, complications were examined postoperatively, follow-up survey was conducted at 6 to 18mo, meanly at 10.05±3.87mo.<p>RESULTS: Recovery of binocular vision: 11 cases did not have binocular vision(50%); 6 cases recovered to the first level of binocular vision(27%); 3 cases recovered to the second level of binocular vision(14%); 2 cases recovered to the third level of binocular vision(9%). The curative effect of DVD shows: 17 cases with satisfaction(77%), 5 cases with improvement(23%), and 0 case with no avail. The curative effect of inferior oblique muscle overaction shows: 13 cases with cured(59%), 9 cases with improvement(41%), and 0 case with no avail. Postoperative eye position and compensatory head posture: 1)Horizontal eye position: 1 case of under correction after exotropia correction surgery, 1 case of under correction after esotropia correction surgery, 0 case of overcorrection, 20 cases of correction; 2)Vertical eye position: 13 cases show vertical strabism deviation less than 5△, 9 cases show vertical strabism deviation between 5△ to 10△ meanly at 5.55△±2.35△, vertical eye position without overcorrection; 3)Compensatory head posture: 6 cases were disappeared, 1 case was improved. Complications: Mild anti-elevation syndromeoccurred in 1 case, narrowed palpebral fissueoccurred in 1 case, and narrowed quantity less than 1mm.<p>CONCLUSION: In general, the curative effect of anterior transposition of the unequal excisional inferior oblique muscle for dissociated vertical deviation with asymmetric inferior oblique muscle overactionis satisfactory, standard preoperative examination, individualized surgical design and surgical techniques are necessary.

Surgical correction of concomitant exotropia combined with inferior oblique weakening procedures for the treatment of children with complex strabismus / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To observe the clinical curative effect of surgical correction of concomitant exotropia combined with weakening procedures in the treatment of children with complex strabismus. <p>METHODS: Totally 68 children(80 eyes)with complex strabismus who were admitted to the hospital from January 2015 to February 2017 were selected. All of them were treated by surgical correction of concomitant exotropia. The clinical diagnosis and treatment were retrospectively analyzed. They were divided into the combined group(<i>n</i>=30, 35 eyes)and the non-combined group(<i>n</i>=38, 45 eyes)according to the implementation of inferior oblique weakening procedures. The visual function, 5m exotropia deviation, degree of inferior oblique muscle overreaction and results of Titmus stereoscopic experiment were compared between the two groups before and after surgery. The postoperative curative effect of both groups was observed.<p>RESULTS: The proportions of patients with simultaneous vision, patients with certain fusion range, patients with distant stereoscopic vision and normal patients with near stereoscopic vision(40-60s)in both groups were significantly increased surgery at 6mo after surgery(<i>P</i><0.05), without significant differences between groups(<i>P</i>>0.05). The degree of inferior oblique muscle overreaction and 5m exotropia deviation in both groups were significantly improved at 6mo after surgery(<i>P</i><0.05), but there was no significant difference between groups(<i>P</i>>0.05). Follow-up of 1-3d, 1a after operation showed there were no significant differences between the two groups in the orthophoria rate, over-correction rate or under-correction rate(<i>P</i>>0.05).<p>CONCLUSION: In the treatment of children with complex strabismus by surgical correction of concomitant exotropia, the combined use of inferior oblique weakening procedures may not affect the correction effects of exotropia. When the surgery is designed, the impact of inferior oblique weakening procedures can be ignored.

Transient Inferior Oblique Muscle Palsy Following Transconjunctival Lower Lid Blepharoplasty / 고신대학교의과대학학술지

Although the inferior oblique (IO) muscle is positioned considerably deep in the orbit, transconjunctival lower lid blepharoplasty may affect it and transient or permanent IO muscle palsy might result. Therefore diplopia should be explained before cosmetic blepharoplasty performed with transconjunctival approach.

Effect of modified inferior oblique anterior transposition on dissociated vertical strabismus patients with inferior oblique muscle hyperfunction / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the effect of anterior transposition of inferior oblique muscle on the treatment of dissociated vertical deviation(DVD)in children with inferior oblique overaction(IOOA)and unequal inferior oblique transposition of the treatment of IOOA with the eyes of the asymmetry of DVD efficacy, associated with the lower oblique hyperfunction DVD patients to provide more effective treatment. <p>METHODS: Eighty patients with hyperfunction who were treated in our hospital from January 2014 to December 2015 were randomly selected and treated with anterior transposition of inferior oblique muscle. Patients were followed up for 1 to 30mo. We compared the vertical incline at the original incline from far(5m), near(33cm)distance and IOOA degree before and after operations, and the correlation between the two. We also compared the vertical incline at the original incline from far(5m), near(33cm)distance and IOOA degree before and after operations in 30 eyes(20 patients)with bilateral asymmetry DVD and IOOA who received unequal inferior oblique transposition. The incidence of antielevation syndrome(AES)was observed after operations. <p>RESULTS: The mean prism diopters(PD)at 5m before operations was 19.5±0.15, the average PD after operations was 3.5±0.18, at 5m the original incline was 16±0.21PD. The mean PD at 33cm was 18.6±0.20 before operation, 4.5±0.26 after operations, and 14.1±0.16 at 33cm the original incline, the difference was statistically significant(<i>P</i><0.05). Preoperatively, inferior oblique muscle hyperfunction +2 and +3 was 50 eyes, + 1 was 20 eyes, and 12 eyes still showed inferior oblique muscle hyperfunction after operation, but the degree of hyperactivity was +1. There was a significant positive correlation between the degree of IOOA and the vertical inclination(33cm: <i>r</i>=0.554, <i>P</i><0.01; 5m: <i>r</i>=0.454, <i>P</i> <0.01). There were significant differences(<i>P</i><0.05)in the vertical incline in 20 patients(30 eyes)with bilateral asymmetry DVD and IOOA and the degree of IOOA was significantly lower. In contrast, 18 patients(24 eyes)underwent anterior transposition of the inferior oblique muscle had AES in different degrees, which had statistically significant difference(<i>P</i><0.05)compared with patients(30 eyes)with IOOA treated with unequal inferior oblique transposition. <p>CONCLUSION: Anterior transposition of the inferior oblique muscle has a good therapeutic effect on isolated vertical strabismus patients with inferior oblique hyperfunction. While the incidence of postoperative AES is low in patients received unequal inferior oblique muscle transposition.

A Valid Indication and the Effect of Bilateral Inferior Oblique Transposition on Recurrent or Consecutive Horizontal Deviation in Infantile Strabismus

PURPOSE: To evaluate the effects of bilateral inferior oblique transposition (BIOT) on horizontal deviation from primary position among patients with bilateral dissociated vertical deviation (DVD) associated with inferior oblique overaction (IOOA) in infantile strabismus. METHODS: Retrospective chart review was conducted among 19 patients with infantile strabismus. All patients had DVD and IOOA with consecutive or recurrent horizontal deviation and underwent modified BIOT surgery. Patients were divided into three subgroups: patients who underwent BIOT (BIOT group, n = 9) alone, BIOT with medial rectus recession or lateral rectus resection simultaneously (ET BIOT group, n = 6), or BIOT with lateral rectus recession or medial rectus resection simultaneously (XT BIOT group, n = 4). Postoperative angle of horizontal deviation (prism diopter, PD) and corrected magnitude of horizontal deviation (PD) at final visit after surgery were analyzed in each group. RESULTS: The mean age was 55.11 ± 21.05 months (range, 32 to 115). The mean follow-up period was 8.68 ± 2.87 months (range, 6 to 18). Preoperative horizontal deviation was 4.23 ± 5.99 PD (range, 0 to 16) in BIOT, −17.33 ± 6.76 PD (range, −30 to −10) in ET BIOT, and 17.50 ± 2.52 PD (range, 14 to 20) in XT BIOT. Esodeviation is represented by negative values. DVD and IOOA were reduced less than +1 in all patients. The corrected amount of horizontal deviation was 3.56 ± 5.18 PD (range, 0 to 16) in BIOT surgery alone and larger in XT BIOT (18.50 ± 3.41 PD) than in ET BIOT (12.33 ± 5.57 PD, p = 0.004). CONCLUSIONS: Minimal exodeviation was corrected by BIOT alone. In addition, secondary eso- or exodeviation at great magnitudes should be corrected with proper horizontal muscle surgery along with BIOT.

Can a dermoid cyst lead to an abnormal origin of an extraocular muscle.

A 5‑year‑old boy presented with a large 5 cm × 5 cm cyst covering the left eye completely since birth. The cyst was excised in toto and was sent for histopathological examination. During the surgery, the inferior oblique (IO) muscle was seen originating from medial orbital wall, 10–12 mm behind the medial orbital margin, just posterior to the lacrimal bone and moving laterally, downward, and posteriorly from its origin making a more acute angle ‑ around 20° to its site of origin. The insertion of the IO to sclera was at its normal site. The abnormal origin of IO was confirmed later by magnetic resonance imaging. The ocular movements of the left eye were tested 2 weeks after the surgery and were found to be normal in all directions. However, the child was hypertrophic and amblyopic. The histopathological findings showed the orbital cyst to contain dermal elements, respiratory, and intestinal epithelium.

The effect of anterior transposition of the inferior oblique muscle on eyelid configuration and function.

Purpose: To evaluate the alteration of lower lid configuration and function with anterior transposition surgery of the inferior oblique (IO) muscle. Patients and Methods: A prospective clinical trial was conducted on a consecutive series of patients underwent anterior transposition of the IO as a sole operation. All patients received a thorough ophthalmic examination 1 day before and 3 months after surgery. Output parameters were consisted of palpebral fissure, margin reflex distance 1–2, lower lid function, hertel value, and lower lid crease. The differences of the collected data were calculated for statistical significance by using the Wilcoxon test. Results: A total of 19 eyes of 16 consecutive patients were included. The median preoperative grade of IO overaction was 3.5 (ranging from 3 to 4), which decreased to 0 (ranging from 0 to 2) postoperatively (P < 0.05). No significant change was observed in all parameters 3 months postoperatively (P > 0.05). Conclusion: In this study, no significant effect on lower lid configuration and function was observed following IO anterior transposition in which the disinserted muscle was placed posterior to inferior rectus insertion.

Changes in Ocular Excyclotorsion According to Graded Inferior Oblique Recession

PURPOSE: To investigate changes in ocular excyclotorsion in patients with inferior oblique overaction (IOOA) according to amount of correction by graded inferior oblique recession and to compare the amount of excyclotorsion between primary IOOA and secondary IOOA. METHODS: This study included 54 eyes of 54 patients who were diagnosed with unilateral IOOA and underwent graded inferior oblique recession. Fundus photographs were taken pre- and postoperatively. The sum of angles of torsion of both eyes was used to analyze changes in excyclotorsion. The angle of excyclotorsion was analyzed using the ImageJ program. RESULTS: Eighteen eyes were grade 2, 24 eyes were grade 3 and 12 eyes were grade 4. Preoperative angle of excyclotorsion was 16.23 ± 5.96° for the patients with grade 2 eyes, 18.83 ± 5.76° for the patients with grade 3 eyes and 29.00 ± 10.23° for the patients with grade 4 eyes. Therefore, as the degree of IOOA increased, the amount of excyclotorsion became larger. There was no statistical significance between grade 2 and grade 3 (p = 0.467), however, there was a statistically significant difference between grade 3 and grade 4 (p < 0.001). Postoperative angle of excyclotorsion was significantly decreased in each group (grade 2: p = 0.020, grade 3: p < 0.001, grade 4: p = 0.041). The amount of surgical recession of inferior oblique muscle showed a positive correlation with a decrease in the angle of excyclotorsion, but was not statistically significant. The amount of excyclotorsion and the decrease of excyclotorsion after surgery were larger in secondary IOOA than in primary IOOA, but were not statistically significant (p = 0.260). CONCLUSIONS: As the preoperative degree of IOOA increased, the amount of correction of excyclotorsion became larger but there is no statistical significance. Correction of IOOA and excylclotorsion is expected after graded inferior oblique recession.

Comparison of Astigmatism Induced by Combined Inferior Oblique Anterior Transposition Procedure and Lateral Rectus Recession Alone

PURPOSE: The purpose of this study is to compare the magnitude and axis of astigmatism induced by a combined inferior oblique (IO) anterior transposition procedure with lateral rectus (LR) recession versus LR recession alone. METHODS: Forty-six patients were retrospectively analyzed. The subjects were divided into two groups: those having concurrent inferior oblique muscle overaction (IOOA) and intermittent exotropia (group 1, 20 patients) and those having only intermittent exotropia as a control (group 2, 26 patients). Group 1 underwent combined anterior transposition of IO with LR recession and group 2 underwent LR recession alone. Induced astigmatism was defined as the difference between preoperative and postoperative astigmatism using double-angle vector analysis. Cylinder power, axis of induced astigmatism, and spherical equivalent were analyzed at 1 week, 1 month, and 3 months after surgery. RESULTS: Larger changes in the axis of induced astigmatism were observed in group 1, with 4.5° incyclotorsion, than in group 2 at 1 week after surgery (axis, 84.5° vs. 91°; p < 0.001). However, there was no statistically significant inter-group difference thereafter. Relaxation and rapid regression in the incyclotorsion of induced astigmatism were observed over-time. Spherical equivalent significantly decreased postoperatively at 1 month in both groups, indicating a myopic shift (p = 0.011 for group 1 and p = 0.019 for group 2) but did not show significant differences at 3 months after surgery (p = 0.107 for group 1 and p = 0.760 for group 2). CONCLUSIONS: Combined IO anterior transposition procedures caused an increased change in the axis of induced astigmatism, including temporary incyclotorsion, during the first week after surgery. However, this significant difference was not maintained thereafter. Thus, combined IO surgery with LR recession does not seem to produce a sustained astigmatic change, which can be a potential risk factor of postoperative amblyopia or diplopia compared with LR recession alone.

Muscular expression of myogenin in V-pattern exotropia with inferior oblique overaction patients / 国际眼科杂志(Guoji Yanke Zazhi)

Abstract?AlM: To study the number of myogenin - positive activated satellite cells in the inferior oblique muscles and the medial muscles of V- pattern exotropia with inferior oblique overaction, to further explore the possible etiological factors of V-pattern exotropia with inferior oblique overaction.? METHODS: The inferior oblique muscles and the medial muscles were cut from V - pattern exotropia patients with inferior oblique overaction during strabismus operation treated as the strabismus group. Cross sections were stained immunohistochemically for the presence of activated satellite cells, as identified by myogenin immunoreactivity. The inferior oblique muscles and the medial muscles were obtained from the corneal transplant donors ( six eyes of six cases) , which treated as the control group.? RESULTS: The frequency of myogenin - positive satellite cells of the inferior oblique muscles was (22. 7± 7.03)% and (4. 2±0. 75)% in the strabismus group and the control group. Significant differences existed in the expression of myogenin in two groups (P<0. 05). Again, the frequency of myogenin-positive satellite cells of the medial muscles was (2. 2±0. 75)% and (4. 5±1. 05)% in the strabismus group and the control group. Significant differences also existed in the expression of myogenin in two groups (P<0. 05).?CONCLUSlON: lt is first report that myogenin-positive satellite cells presents in extraocular muscles of V -pattern exotropia with inferior oblique overaction. The current results suggest that myogenin is one of possible etiological factors of V-pattern exotropia with inferior oblique overaction.

The Effect of Inferior Oblique Muscle Transposition in Primary and Secondary Inferior Oblique Muscle Overaction

PURPOSE: To evaluate and compare the effect of transposition of inferior oblique muscle in patients with primary inferior oblique muscle overaction and secondary due to superior oblique muscle palsy. METHODS: The present study included 41 patients (53 eyes), who appeared to have primary or secondary inferior oblique muscle overaction due to superior oblique muscle palsy and received transposition of inferior oblique muscle with at least 3 months of follow-up. Patients were retrospectively analyzed to compare the effect of correction and its prognosis. Inferior oblique muscle overaction was graded as +1 to +4 according to the severity. Successful surgery was defined as postoperative inferior oblique muscle overaction from 0 to +1 and failure as above +2. Hypertropia in primary gaze was also recorded to evaluate the effect of correction. RESULTS: Twenty-six (35 eyes) and 15 (18 eyes) patients with primary and secondary inferior oblique muscle overaction due to superior oblique muscle palsy, respectively, received transposition of inferior oblique muscle. Patients with primary inferior oblique muscle overaction showed correction of 2.1 +/- 0.9 with preoperative inferior oblique muscle overaction of 2.0 +/- 0.7. Patients with secondary inferior oblique muscle overaction showed a correction of 2.3 +/- 0.9 with preoperative value of 2.3 +/- 0.8. Each 3.2 +/- 4.1 prism diopters (PD) and 6.5 +/- 5.3 PD of hypertropia at primary gaze showed correction of 3.0 +/- 7.4 PD and 6.3 +/- 5.1 PD, respectively, in each group. CONCLUSIONS: Primary and secondary inferior oblique muscle overaction due to superior oblique muscle palsy showed no difference in correction of overaction and hypertropia after transposition of inferior oblique muscle. Except for presence of inferior oblique muscle underaction, the correction appears effective with good prognosis.

Contralateral Inferior Oblique Muscle Overaction after Unilateral Inferior Oblique Weakening Procedures

PURPOSE: To investigate the effect of unilateral inferior oblique weakening procedures on contralateral inferior oblique muscle functions and factors that may have an effect on contralateral inferior oblique muscle overaction (IOOA). METHODS: A retrospective chart review was conducted of medical records of 40 patients who underwent unilateral inferior oblique (IO) muscle weakening procedures from 2007 to 2011 and were observed during a follow-up period of more than 6 months. These patients were composed of primary IOOA (4 patients), secondary IOOA due to superior oblique muscle (SO) palsy (21 patients), secondary IOOA due to inferior rectus muscle palsy (1 patient), and dissociated vertical deviation (DVD) accompanied with IOOA (14 patients). Factors that may have an effect on contralateral IOOA after undergoing the operation were assessed. RESULTS: There were 7 patients (17.5%) who had over +2 IOOA after operation. IOOA on contralateral eye was increased from average of +0.00 to average of +0.66 +/- 0.14 in 6 months after operation (p < 0.01). There were no statistically significant differences between preoperative factors and functional changes in contralateral IO muscle. CONCLUSIONS: There were no statistical factors that may have an effect on contralateral IOOA but the possibility of masked SO palsy before performing unilateral IO weakening procedures should be considered. In patients who have unilateral DVD associated with IOOA or small hypertropia, the contralateral IOOA can be more definite after operation; thus caution should be taken before operation.

Effect of Inferior Oblique Weakening Procedures Combined with Surgery for Intermittent Exotropia

PURPOSE: To investigate whether combining inferior oblique weakening procedures with bilateral lateral rectus recession as a surgical approach to intermittent exotropia enhances postoperative horizontal angle of deviation over bilateral lateral rectus recession alone. METHODS: Patients were allocated to one of two surgical groups: a bilateral lateral rectus recession group (Group 1) or a bilateral lateral rectus recession with bilateral inferior oblique weakening group (Group 2). Group differences in the angle of distance deviation were evaluated preoperatively and at 3- and 12-months postoperatively. RESULTS: There were no significant differences in preoperative factors or angles of deviation between Group 1 (n = 98) and Group 2 (n = 77); no significant intergroup difference in the angle of deviation was observed at any postoperative time point (p > 0.05). CONCLUSIONS: Combined inferior oblique weakening procedures did not significantly influence the horizontal angle of deviation after surgery for intermittent exotropia. Accordingly, there is no need to revise the surgical amount of lateral rectus recession.

Evaluation of macular thickness change after inferior oblique muscle recession surgery.

Purpose: This study aimed to evaluate the changes in macular thickness following inferior oblique muscle recession surgery. Materials and Methods: Thirty‑eight eyes from 21 patients undergoing ocular muscle surgery were included. Patients were grouped into three groups based on the type of surgical intervention: Group I (n = 12), inferior oblique recession surgery alone; Group II (n = 12), inferior oblique plus horizontal muscle surgery; Group III (n = 14), horizontal muscle surgery alone. Each eye was scanned using the optical coherence tomography (OCT) device preoperatively and on the first postoperative day to measure macular thickness. Results: Following surgery, a significant increase in foveal thickness occurred in Group I (P < 0.05) and Group II (P < 0.01). In addition, a statistically significant difference was observed between the groups with regard to the increase in foveal thickness (P = 0.016), with significantly lower changes in Group III. Conclusion: Our findings suggested that inferior oblique muscle recession surgery is associated with an increase in macular thickness.