Inferior Oblique Anterior Transposition Research Articles

Fundus torsion following inferior oblique muscle weakening

PurposeTo determine the postoperative fundus torsion following surgical inferior oblique (IO) weakening in patients with inferior oblique overaction (IOOA). MethodsIn this interventional case series, 37 patients with IOOA ≥ +1 and reliable preoperative fundus photographs were included. IO weakening was accomplished through myectomy or anterior transposition. Fundus photography was repeated at 3 months’ follow-up. The primary outcome was change of disk foveal angle (DFA), measured as the angle between the line connecting the center of the fovea and optic disk and horizontal. Success or normal fundus torsion was defined as a postoperative angle of 0° to 8° of extorsion. Residual extorsion was defined as postoperative extorsion of > 8°. Postoperative intorsion was defined as any amount of induced intorsion. ResultsMean age of patients (56% females) was 6.46 ± 6.79 years. At follow-up at least 3 months after surgery, the mean change of DFA was 7.79 ± 6.24° of reduction of extorsion after IO myectomy (P < 0.001) and 6.05 ± 6.07° after IO anterior transposition (P = 0.005). Normal fundus torsion was achieved in 50% of patients after myectomy and 36.4% of patients after anterior transposition. Residual extorsion was observed in 49% of patients; induced intorsion in 5%. ConclusionsUsing objective measurement of fundus photographs, fundus extorsion was decreased in 94.7% of patients after myectomy or anterior transposition.

Inferior Oblique Anterior Transposition versus Myectomy for Inferior Oblique Overaction: Systematic Review and Meta Analysis.

The objective of this study was to compare the outcomes of inferior oblique anterior transposition (IOAT) versus inferior oblique myectomy (IOM) in patients with primary inferior oblique overaction (IOOA) or secondary IOOA to superior nerve palsy. A systematic review and meta-analysis were performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Guidelines and an electronic search was conducted to identify studies comparing IOAT versus IOM for IOOA. Residual inferior oblique function, reduction in hypertropia and post-operative complications were identified as primary outcomes. Secondary outcomes included superior oblique function, head tilt improvement, effect on the contralateral eye, operation time and macular changes. The analysis was based on fixed or random-effects modelling. Eleven studies enrolling 729 patients were identified. Inferior oblique function was not significantly different between both interventions, namely the elimination of IOOA (Odds Ratio[OR] = 0.97, P = 0.97), reduction in IOOA (Mean Difference[MD] = -0.06, P = 0.68), post-operative inferior oblique under-action (OR = 1.06, P = 0.83) and residual overaction (OR = 0.71, P = 0.15). Similarly, no significant difference was noted between both groups in reducing hypertropia. Regarding post-operative complications, no significant difference was observed, including the incidence of anti-elevation syndrome (P = 0.10). No significant difference was noted regarding superior oblique function, improvement in head tilt, effect on the contralateral eye and macular changes, although surgical time was shorter in the IOM group. In conclusion, IOAT and IOM are both effective surgical procedures in the management of IOOA as they produced comparable outcomes in the improvement in hypertropia, post-operative inferior oblique function and incidence of complications.

Inferior oblique anterior transposition according to a different grading scale for hyperdeviation with inferior oblique overaction

ObjectifDéfinir une échelle de classement de la transposition antérieure de l'oblique inférieur (IOAT, pour inferior oblique anterior transposition) chez des patients présentant une hyperdéviation et une hyperaction de l'oblique inférieur (IOOA, pour inferior oblique overaction), selon des données issues de notre étude rétrospective antérieure. NatureÉtude de cohorte prospective. ParticipantsTrente-huit patients qui ont fait l'objet d'un classement de l'IOAT. MéthodesLes patients ont été répartis en 5 groupes en fonction de l'importance de l'hyperdéviation en position primaire (PPHD, pour primary position hyperdeviation). L'oblique inférieur a été transposé soit à 2 mm postérieur, à 1 mm postérieur, en parallèle, à 1 mm antérieur ou à 2 mm antérieur à l'insertion du droit inférieur, respectivement. La réussite de l'intervention chirurgicale se définissait comme suit : réussite complète (PPHD ≤ 3 dioptries prismatiques [DP]), réussite partielle (PPHD > 3 et ≤ 6 DP) et échec (PPHD > 6 DP). RésultatsLa correction moyenne de l'hyperdéviation par groupe après l'IOAT se chiffrait à 9,50 ± 0,9 DP (fourchette : 8–10 DP), à 12,43 ± 1,5 DP (fourchette : 11–14 DP), à 16,67 ± 1,4 DP (fourchette : 15–18 DP), à 19,57 ± 1,7 DP (fourchette : 16–21 DP) et à 22,57 ± 5,8 DP (fourchette : 14–30 DP), respectivement. L'intervention a été une réussite chez 34 patients (89,5 %), une réussite partielle chez 3 patients (7,9 %) et un échec chez 1 patient (2,6 %). Tous les patients de notre étude présentaient une IOOA unilatérale avant l'intervention; une IOOA est apparue dans l’œil controlatéral de 9 patients (23,7 %) pendant le suivi postopératoire. Une limitation de –2 du regard vers le haut est apparue chez 4 patients (57,1 %) du groupe 5, sans qu'il soit besoin de recourir à la chirurgie. ConclusionsIl est possible d'obtenir un taux élevé de réussite grâce à notre échelle de classement de l'IOAT en présence d'IOOA primaire et secondaire s'accompagnant d'une hyperdéviation en position primaire.

Different Surgical Approaches for treatment of isolated dissociated vertical deviation without inferior oblique overaction.

To report the surgical results on superior rectus recession (SRR) and inferior oblique anterior transposition (IOAT) for cases with isolated bilateral dissociated vertical deviation（DVD）without inferior oblique overaction (IOOA). A retrospective review was conducted for cases with isolated bilateral DVD without IOOA who were surgically treated using either bilateral SRR (SRR group) or IOAT (IOAT group). Pre- and post-operative ocular motility, ocular alignment, amount of DVD and complications were compared between the two groups. Records from 37 cases were reviewed. Preoperative levels of DVD (M ± SD) in the SRR group (N = 18) of 19.88 ± 6.72 prism diopter (PD) in the right eye and 19.54 ± 5.64 PD in the left eye, were reduced to 4.94 ± 7.26 PD and 4.11 ± 3.91 PD respectively after surgery (P＜0.0001 for both). Preoperative levels of DVD (M ± SD) in IOAT group (N = 19) of 15.89 ± 6.35 PD in the right eye and 18.58 ± 9.27 PD in the left eye, were reduced to 3.42 ± 4.49 PD and 3.42 ± 4.88 PD respectively after surgery (P＜0.0001 for both). Inferior oblique (IO) muscle function remained normal after surgery. Overall, outcomes within the SRR group revealed that 10 patients showed a complete resolution of their condition, 6 effective responses and 2 failures. In the IOAT group, 13 patients showed a complete resolution of their condition, 5 effective responses and 1 failure. There were no statistically significant differences between the two groups (Z = 0.48). SRR and IOAT were both effective in treating isolated DVD without IOOA with similar satisfactory results obtained for both procedures.

Augmented lateral rectus muscle recession for treatment of infantile exotropia.

The surgical outcome is usually not satisfactory for treatment of primary infantile exotropia (PIE) with large exodeviation angels of more than 50 prism diopters (PD). Here, we evaluate the effectiveness of augmented bilateral lateral rectus muscle recession (ABLRR) in treatment of PIE with large deviation angles. A retrospective analysis was performed for 25 patients with PIE who underwent ABLRR. ABLRR was performed using a hemi-hang-back technique. Ocular alignment, ocular motility and binocular vision were evaluated pre- and postoperatively. Fourteen males and 11 females with PIE were included in this study, with a mean age of (3.92 ± 2.02) years (range, 1-7years). The average exodeviation angle was (-66.32 ± 7.84) PD (range, -60--80 PD) preoperatively. All patients underwent ABLRR using the hemi-hang-back technique. Three of them underwent bilateral inferior oblique muscle anterior transposition in the same operation. The mean surgical dosage was (11.08 ± 1.19) mm for each lateral rectus muscle. The mean of deviation angel was -2.28 ± 5.08 PD postoperatively (P < 0.05). All patients did not have abduction deficiency after a large amount of lateral rectus recession. Twenty-one of 25 patients (84.0%) achieved orthophoria at the primary gaze position at the final visit, and 13 patients obtained binocular vision. ABLRR is an effective and safe surgical procedure for treatment of PIE with a large deviation angle.

Surgical outcomes of three different weakening procedures of inferior oblique muscle in the treatment of unilateral superior oblique palsy

BackgroundTo compare surgical outcomes and complications of three inferior oblique weakening procedures; Inferior Oblique Myectomy (IOM), Inferior Oblique combined Resection-Anterior Transposition (IORAT) and Inferior Oblique Anterior Transposition (IOAT) in the management of unilateral Superior Oblique (SO) palsy.MethodsRetrospective review of medical records of all patients with unilateral SO palsy who underwent one of the aforementioned IO weakening procedures at Benha University hospital was performed. Patients were excluded if surgery was bilateral or combined with other vertical muscle surgery. Primary outcome parameters were improvement of Hypertropia (HT) in primary gaze, side gazes, on alternate head turn, Inferior Oblique Overaction (IOOA), Superior Oblique Underaction (SOUA), correction of head tilt and postoperative complications.ResultsThe review reveals a total of 65 patients with unilateral SO palsy; 54 congenital and 11 acquired, who met the study criteria and were classified into 3 groups; IOM group (24cases), IORAT group (19cases) and IOAT group (22cases). Compared with IOM, both IORAT and IOAT induced significant correction of HT in primary position, ipsilateral gaze, contralateral head tilt and IOOA. IORAT was significantly more effective than IOAT in correction of HT in ipsilateral gaze and contralateral head tilt while there was no statistical difference between the three groups in correction of HT in ipsilateral gaze, contralateral head tilt and SOUA. Postoperative Anti-elevation was significantly recorded following IORAT (6 cases, 31%) than IOAT (3 cases, 13%) and IOM (one cases, 4%).ConclusionsThe IORAT and IOAT were more superior to IOM in correction of IOOA and HT in the primary position and some other gaze positions. However, superiority of IORAT over the other two procedures should be weighed against its significant association with postoperative underaction of IO muscle and anti-elevation syndrome.

Instantaneous Reconstruction of Inferior Rectus: Asset for Vision

Orbital lesions are frequent findings after blunt periocular trauma causing diplopia, muscle avulsion etc. Four patients presented with diplopia after a penetrating injury to the right eye. Examination revealed right hypertopia and limitation of infraduction of right eye with rupture of Inferior Rectus. Immediate repair of inferior rectus muscle with anterior transposition of inferior oblique is a safe and effective procedure to restore motility

Unilateral inferior oblique anterior transposition for markedly asymmetric dissociated vertical deviation with unilateral inferior oblique over-action

BackgroundTo evaluate the results of unilateral inferior oblique anterior transposition (IOAT) for markedly asymmetric dissociated vertical deviation (DVD) combined with inferior oblique over-action (IOOA).MethodsRetrospective chart review of the records of all patients with asymmetric DVD combined with unilateral IOOA in the non-dominant eye who received unilateral IOAT on the non-dominant eye. No other muscles were operated on simultaneously. The amount of DVD and IOOA were measured before and after the operation and statistically analysed.ResultsSeventeen patients were included. The mean age at surgery was 23.5 ± 8.4 (range 12–38) years old. The mean postoperative follow-up period was 15.7 ± 7.2 (range 6–32) months. The primary position DVD was 19.6 ± 5.4 (range 14–36) PD preoperatively and decreased significantly to 2.9 ± 2.0 (range 0–8) PD postoperatively (P < 0.01). Preoperatively, there were 2, 7, and 8 patients with + 1, + 2, and + 3 IOOA, respectively, and these were reduced from 2.4 ± 0.7 to 0.3 ± 0.4 postoperatively (P < 0.01). None of the patients were complicated obvious hypotropia, anti-elevation syndrome or IOOA in the contralateral eye.ConclusionsUnilateral IOAT was recommended in patients with asymmetric DVD coexists with unilateral IOOA.

Does it work? the inferior oblique anterior nasal transposition (IOANT)—procedure with short tag noose adjustable sutures in treating 4th nerve palsy with large angle deviation

Does it work? the inferior oblique anterior nasal transposition (IOANT)—procedure with short tag noose adjustable sutures in treating 4th nerve palsy with large angle deviation

Modified anterior transposition of the inferior oblique muscle

To introduce a modified method of anterior transposition of inferior oblique (ATIO) and compare with traditional method in terms of efficacy and complications. The medical records of patients who had undergone unilateral ATIO and were followed for at least 6months were reviewed retrospectively. The patients were divided into two groups according to the surgical method: modified ATIO (modified group, n=16) and traditional ATIO (traditional group, n=15). In modified ATIO, the anterior nasal fibers of the inferior oblique muscle were anchored to the sclera and the posterior temporal fibers were folded and buried under the fixed anterior nasal fiber of inferior oblique muscle. In the traditional method, both the anterior and posterior fibers were fixed with individual suturing. Postoperative change in vertical deviation and grade of inferior oblique overaction (IOOA) were analyzed. Complications, including antielevation syndrome, fat adherence syndrome, and lower lid deformity were assessed. Both modified and traditional methods effectively weakened the action of the inferior oblique muscle. The efficacy of the two methods did not differ in terms of change in vertical deviation (P=0.225) and grade of IOOA (P=0.169). Antielevation syndrome occurred more frequently in the traditional group than in the modified group (8/15 vs 2/16, resp. [P=0.019]). Incidences of fat adherence syndrome (0/15 vs 0/16 [P=1.0]) and lid deformity (3/15 vs 1/15 [P=0.678]) were not different. Modified ATIO was comparable to traditional ATIO in correcting vertical deviation and IOOA and had a lower risk of antielevation syndrome compared with traditional ATIO.

Effect of inferior oblique anterior transposition in correcting vertical hyperdeviation in primary position

ObjectiveTo evaluate the effect of inferior oblique anterior transposition (IOAT) on improvement of vertical hyperdeviation in primary position. MethodsThis study was a retrospective review and included 35 eyes of 33 patients (18 males and 15 females). Patients with dissociated vertical deviation were not included in the study. Preoperative and postoperative average follow-up was 11.46 ± 11.73 and 11.43 ± 9.73 months, respectively. The eyes were divided into 5 groups according to the amount of transposition. Inferior oblique muscle was transpositioned 2 mm posterior to the inferior rectus insertion in group 1; 1 mm posterior to the inferior rectus insertion in group 2; parallel to the inferior rectus insertion in group 3; 1 mm anterior to the inferior rectus insertion in group 4; and 2 mm anterior to the inferior rectus insertion in group 5. ResultsThe mean preoperative and postoperative vertical hyperdeviation were 16.52 ± 5.54 and 0.97 ± 2.34 prism diopters (PD), respectively. The mean preoperative vertical hyperdeviation in group 1, group 2, group 3, group 4, and group 5 was 11.0 ± 4.24, 12.88 ± 4.26, 16.63 ±3.50, 19.83 ± 2.71, and 25.5 ± 3.00 PD, respectively. Postoperatively, improvement in vertical hyperdeviation in group 1, group 2, group 3, group 4, and group 5 was 11.0 ± 4.24, 11.63 ± 3.20, 15.46 ± 3.19, 18.17 ± 2.23, and 25.5 ± 3.00 PD, respectively. The vertical hyperdeviation had improved 100% in group 1; 90.2% in group 2; 92.9% in group 3; 91.59% in group 4; and 100% in group 5. ConclusionIOAT surgery planned according to hyperdeviation amount has effective and predictable results in correcting vertical hyperdeviation in primary position.

Simultaneous Superior Rectus Recession and Anterior Transposition of Inferior Oblique Muscle as a Surgical Option for Traumatically Lost Inferior Rectus Muscle

ABSTRACTPurpose: To evaluate the role of simultaneous superior rectus (SR) recession and anterior transposition of inferior oblique (ATIO) muscle in patients with traumatically lost inferior rectus (IR) muscle.Methods: Six patients with history of ocular trauma, followed by sudden onset vertical diplopia along with marked hypertropia (HT) and limitation of depression in abduction in the affected eye suggestive of IR disinsertion, were included in this prospective study. The patients were treated by simultaneous SR recession and ATIO muscle in the affected eye by limbal conjunctival approach under local anesthesia.Results: Preoperatively, primary position HT of 40–50 (mean 44.16 ± 4.91) prism diopters (PD) was present in all cases which increased to 65–70 (mean 65.83 ± 5.84) PD in down and in the ipsilateral gaze along with marked limitation of depression in abduction and A pattern. On exploration, the IR could not be traced in four cases. Fibrotic muscle sheath with retracted IR was found 10–12 mm away from the limbus in rest of the two patients. ATIO (6.5 mm from the limbus) with simultaneous recession of ipsilateral SR was done under local anesthesia.At 12 weeks postoperatively, three patients were orthophoric in primary position and vertical alignment with in 4–7 PD in primary position was achieved in rest of the three patients.Conclusion: Simultaneous SR recession with ATIO seems to be a good alternative to achieve satisfactory vertical alignment for patients with traumatically lost inferior rectus muscle.

Surgical interventions for vertical strabismus in superior oblique palsy.

Superior oblique palsy is a common cause of vertical strabismus in adults and children. Patients may be symptomatic from binocular vertical diplopia or compensatory head tilt required to maintain single vision. Most patients who are symptomatic elect to undergo strabismus surgery, but the optimal surgical treatment for vertical strabismus in people with superior oblique palsy is unknown. To assess the relative effects of surgical treatments compared with another surgical intervention, non-surgical intervention, or observation for vertical strabismus in people with superior oblique palsy. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 12), MEDLINE Ovid (1946 to 13 December 2016), Embase Ovid (1947 to 13 December 2016), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to 13 December 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch); searched 13 December 2016, ClinicalTrials.gov (www.clinicaltrials.gov); searched 13 December 2016, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 13 December 2016. We did not use any date or language restrictions in the electronic searches for trials. We included randomized trials that compared at least one type of surgical intervention to another surgical or non-surgical intervention or observation. Two review authors independently completed eligibility screening, data abstraction, 'Risk of bias' assessment, and grading of the evidence. We identified two randomized trials comparing four different surgical treatments for this condition, two methods in each trial. The studies included a total of 45 children and adults. The surgical treatments were all procedures to weaken the ipsilateral inferior oblique muscle. One study compared inferior oblique myectomy to recession of 10 mm; the other study compared inferior oblique disinsertion to anterior transposition (2 mm anterior to the temporal border of the inferior rectus insertion).We judged both studies to be at unclear risk of bias due to incomplete reporting of methods and other methodological deficiencies.Neither study reported data on the primary outcome of this review, which was the proportion of participants with postoperative surgical success, defined as hypertropia less than 3 prism diopters (PD) in primary gaze. However, both studies reported the average reduction in hypertropia in primary gaze. One study found that at 12 months' postoperatively the average decrease in hypertropia was higher in participants who underwent inferior oblique myectomy than in those who underwent recession, however data were not available for statistical comparison. The other trial found that after at least six months of follow-up, the mean decrease in primary position hypertropia was lower in participants who underwent inferior oblique disinsertion than in those who underwent anterior transposition (mean difference (MD) -5.20 PD, 95% confidence interval (CI) -7.76 to -2.64; moderate-quality evidence).Both trials also reported the average postoperative reduction in vertical deviation in adduction. One study reported that the average reduction in hypertropia in adduction was greater in participants who underwent inferior oblique myectomy than in those who underwent recession, but data were not available for statistical comparison. The other study found a lower decrease in hypertropia in contralateral gaze in participants who underwent inferior oblique disinsertion than in those who underwent anterior transposition (MD -7.10 PD, 95% CI -13.85 to -0.35; moderate-quality evidence).Secondary outcomes with sufficient data for analysis included proportion of participants with preoperative head tilt that resolved postoperatively and proportion of participants who underwent a second surgery. These outcomes were assessed in the trial comparing inferior oblique anterior transposition to disinsertion; both outcomes favored anterior transposition (risk ratio 7.00, 95% CI 0.40 to 121.39 for both outcomes; very low-quality evidence). None of the participants who underwent inferior oblique anterior transposition or disinsertion developed postoperative hypotropia or reversal of the vertical deviation. All participants who underwent inferior oblique anterior transposition developed elevation deficiency, which the authors deemed to be clinically insignificant in all cases, whereas no participants who underwent inferior oblique disinsertion experienced this complication. Additionally, the trial comparing inferior oblique myectomy to recession reported that no participant in either group required another strabismus surgery during the postoperative period. The two trials included in this review evaluated four inferior oblique weakening procedures for surgical treatment of superior oblique palsy. We found no trials comparing other types of surgical procedures for this disorder. Both studies had enrolled a small number of participants and provided low-quality evidence due to limitations in completeness and applicability. We therefore found no high-quality evidence to support recommendations for optimal surgical treatment of superior oblique palsy. Rigorously designed, conducted, and reported randomized trials are needed to identify the optimal surgical treatment for vertical strabismus in this disorder.

Graded versus ungraded inferior oblique anterior transposition in patients with asymmetric dissociated vertical deviation

To report the surgical outcomes of graded versus ungraded inferior oblique anterior transposition (IOAT) in treatment of patients with asymmetric dissociated vertical deviation (DVD) and bilateral inferior oblique overaction (IOOA). A total of 74 eyes of 37 patients with asymmetric DVD (interocular difference of ≥5Δ) and bilateral IOOA of > +1 were included in this randomized clinical trial. In the ungraded group (n=18), both inferior oblique muscles were sutured at the inferior rectus level; in the graded group (n=19), the inferior oblique muscles of eyes with more DVD were sutured at the level of the inferior rectus and inferior oblique muscles of eyes with less DVD were sutured 2mm posterior to the level of the inferior rectus muscle. DVD was significantly reduced in each group (P<0.001 for both). Although the postoperative mean difference of asymmetry of DVD was less in the ungraded group compared to the graded group (1.2±1.9 vs 3.2±1.2 [P=0.001]), the absolute amounts of reduction of DVD asymmetry were similar (4.3±2.3 vs 4.4±3.1 [P=0.78]). IOOA and V patterns were also reduced postoperatively. Each method of IOAT was effective in reducing DVD, asymmetry, IOOA, and V patterns.

Anterior and nasal transposition of inferior oblique muscle in cases of superior oblique palsy

To report long-term outcome of inferior oblique anterior and nasal transposition in superior oblique palsy. The medical records of patients with superior oblique palsy who underwent inferior oblique anterior nasal transposition were reviewed retrospectively. A comprehensive ophthalmic evaluation, including prism bar cover test and measurement of torsion, was performed for all cases. One-year postoperative results were evaluated for alignment in primary gaze, contralateral gaze, and upgaze; reduction in inferior oblique overaction and changes in fundus torsion to assess long-term outcome of the procedure. A total of 12 patients were included. Three cases also underwent horizontal muscle surgery. Mean age at the time of surgery was 20.6years. The median preoperative hypertropia was 21.5Δ (range, 12Δ-36Δ), corrected to 4.5Δ (range, 2Δ-10Δ) at 12months postoperatively (P=0.002). Median inferior oblique overaction decreased from +3 (range, +1 to +4) to 0 (range, -1 to +1). Preoperative fundus extorsion was 19.2° ± 6.7°; postoperative, 0.58° ± 1.8° (P<0.001). No consecutive hypotropia or underaction in elevation was observed in 10patients; 1 patient complained of torsional diplopia in upgaze. Extorsion was eliminated and head tilt improved in all patients. Inferior oblique anterior and nasal transposition resulted in good long-term outcomes in our patients with superior oblique palsy presenting with hypertropia, inferior oblique overaction, and extorsion in primary gaze.

Inferior Oblique Anterior Transposition in the Treatment of Upshoot in Duane Syndrome

Purpose: We report the procedure of inferior oblique anterior transposition (IOAT) in the treatment of upshoot in patients with Duane retraction syndrome (DRS). Methods: Two patients with DRS underwent surgery for severe up-shoot. For both patients, the inferior oblique (IO) was transposed to the temporal border of IO insertion. Approximately 64 months of periodic follow-ups for Case 1 and 7 months of periodic follow-ups for Case 2 were conducted. Results: After surgery, both patients showed a marked decrease in upshoot without noticeable anti-elevation syndrome. Conclusions: IOAT is an effective procedure in the treatment of significant upshoot in DRS

Surgical management of superior oblique paresis using inferior oblique anterior transposition.

Inferior oblique anterior transposition (IOAT) is an effective surgical procedure for weakening the inferior oblique muscle. The purpose of this study was to assess the effectiveness and complications of IOAT for superior oblique paresis at a single center over a period of 11 years. The medical records of consecutive patients treated for congenital and acquired fourth nerve paresis with IOAT procedures at Addenbrookes Hospital, Cambridge, from 2001 to 2012 were retrospectively reviewed. All patients were examined before and after surgery: the vertical deviation in primary position and on contralateral gaze was measured, as were versions. The data collected included patient sex and age, presenting complaint, follow-up period, abnormal head position before and after surgery, postoperative complications, and further operative procedures. A total of 98 IOAT procedures were reviewed, with a mean follow-up of 5.8 months. The technique produced a mean correction of 9.5(Δ) in primary position and 17(Δ) in contralateral gaze. Inferior oblique overaction was reduced in all cases, with 20% having a residual overaction and 47% having an underaction. No patients had symptomatic antielevation syndrome. In this patient cohort, IOAT effectively managed appropriately selected patients with superior oblique paresis, improving the vertical deviation in primary position and contralateral gaze. The procedure induced limitation of elevation in some patients. No patient experienced major postoperative symptoms.

Comparison of outcome of inferior oblique weakening procedures, myectomy and anterior transposition, from western India

Context: Inferior oblique (IO) weakening is one of the commonest surgical procedures on the oblique muscles. Purpose: To compare the results of two IO weakening procedures, myectomy, and anterior transposition, done for IO over-action and dissociated vertical deviation (DVD). Setting and design: Tertiary eye-care center. Retrospective review Materials and Methods: Patients operated for IO over-action and DVD were studied. All patients had undergone a comprehensive ocular examination with full orthoptic evaluation and cycloplegic refraction. In the anterior transposition of IO, the IO muscle was recessed from its insertion and placed lateral to the insertion of the inferior rectus. In myectomy, the IO tendon was cut at two sites 5 mm apart and the cut ends cauterized and left free. The outcome measure was pre and post-operative IO action measurement. Statistical analysis: T-test. Results: Eighty six children (128 eyes) underwent IO weakening procedures, 81 (62.4%) were myectomy and 47 (36.2%) were anterior transpositions. The average age was 8.9 years (standard deviation, SD 3.51), 53 (61.6%) were girls. Twenty-three had DVD and 42 patients had bilateral IO surgeries. Thirty-eight (44.2%) had esotropia and 47 (54.6%) had exotropia co-existent; one had only primary IO over-action. The pre-and post-operative IO over-action was 1.61 and 0.59 for myectomy and 1.61 and 0.29 for anterior transposition, respectively. On comparing the pre- vs post-IO action, P < 0.001 for both techniques, but post-operative anterior transposition versus myectomy had P = 0.156 by the t-test. Conclusion: Both techniques were effective and the difference between the two techniques was not statistically significant.

New surgical intervention for the weakening of the inferior oblique muscle: equatorial scleral anchor.

To evaluate the efficacy of a new surgical technique in reducing inferior oblique muscle overaction. Anterior transposition and myectomy of the inferior oblique muscle represent the gold-standard treatment in dissociated vertical deviation, including cases in which a simultaneous inferior oblique muscle overaction is also present. A new surgical procedure that consists of suturing the muscle to the sclera at the Gobin point with tendon sparing using a micro-incision to minimize the related tissue trauma and induce a faster recovery was developed. Two of 8 patients with essential infant esotropia had a complete resolution of the elevation in adduction with no residual vertical imbalance. All patients experienced an improvement in lateral incomitance. The new "equatorial scleral anchor" surgical procedure gives a similarly good outcome when compared with the classic inferior oblique anterior transposition technique, with the advantages being simple, safe, reversible, and modular in terms of suturing.

Inferior oblique anterior transposition for the unilateral hypertropia associated with bilateral inferior rectus muscle aplasia

Bilateral inferior rectus muscle aplasia in the absence of craniofacial abnormality is a rare but possibly under-recognized form of strabismus. Unilateral hypertropia in primary position seems to be a recurrent feature of this condition. We report a case of a 20-year-old woman with left hypertropia in primary position who was found on computed tomography to have bilateral inferior rectus muscle aplasia. A unilateral inferior oblique anterior transposition resulted in correction of the vertical deviation in primary position.