Hypertropia In Primary Position Research Articles

One- vs Two- vertical muscle surgery in the management of unilateral superior oblique muscle palsy with hypertropia over 20 PD

ABSTRACT Purpose: To compare the surgical outcomes of One- versus Two-vertical muscle surgery in patients with unilateral superior oblique muscle palsy (SOP) with primary position hypertropia (HT) over 20 PD. Patients in Group 1 underwent inferior oblique anterior transposition plus resection (IOATR), while patients in Group 2 underwent inferior oblique anterior transposition (IOAT) along with contralateral inferior rectus (IR) recession. Methods: Medical data of all SOP patients treated by either procedure from 2000 to 2023 in our strabismus center were recruited. We compared surgical outcomes between Group 1 and Group 2 by analyzing HT correction, rate of under-correction, and over-correction. Results: The study included 33 patients in Group 1 and 23 in Group 2. Both groups were similar in age, sex, etiology, affected side, diplopia, and head tilt. Group 2 achieved higher HT correction in all measured gazes. Group 1 had a higher risk of under-correction (18.18% in Group 1 vs 8.69% in Group 2) while Group 2 had a higher rate of over-correction (21.73% vs 0% in Group 1). Conclusion: In patients with severe unilateral SOP, Two-vertical muscle surgery achieved higher amounts of HT correction in all gazes despite a significantly higher risk of over-correction.

Clinical outcomes of inferior oblique myectomy in age categorized patients with unilateral superior oblique palsy

BackgroundUnilateral superior oblique palsy (SOP) is the most common isolated cranial nerve palsy. This report looks at the results and safety of inferior oblique (IO) myectomy for SOP. MethodsA retrospective chart review of patients with fusional ability who underwent IO myectomy for unilateral SOP over a 15-year period, at one of our university-associated health care centers. Primary outcomes were: distance hypertropia and excyclotropia in primary position, inferior oblique overaction (IOOA) and the correlation between the age at surgery and the residual distance hypertropia. ResultsA total of 73 patients with unilateral SOP who underwent IO myectomy were included in the analysis. Mean pre-operative values were: distance hypertropia: 15.41 ± 6.8 Prism Diopters (range 4–30 PD), IOOA: +2.2 ± 0.7 (range 0–3.5) and excyclotropia: +5.34 ± 3.6° (range 0–12°). Mean post-operative values were: distance hypertropia: 3.7 ± 3.4PD [0-14PD], IOOA: −0.1 ± 0.8 [(-2)-2] and excyclotropia: +1.1 ± 2.3°[(-5)-10]. The younger age group (0–20 years old) had a trend toward smaller preoperative distance hypertropia (P = 0.051), and a significantly smaller distance hypertropia post-operatively (p = 0.007). There was no case of ocular complication. ConclusionsOn average, IO myectomy results in a 11.7PD reduction of the distance hypertropia, and 4° reduction of excyclotropia, with an effective reduction of IOOA. While these results are comparable to other surgical methods reported in the literature, they underline an efficacy without the risks of complications such as anti-elevation syndrome and possible scleral perforation. The younger age group had a trend toward smaller preoperative deviation, and better outcomes compared to the older age group.

Transposition of the inferior oblique muscle belly without disinsertion for overshoot in adduction treatment

PurposeTo evaluate the efficacy and safety of inferior oblique muscle transposition and myopexy in patients with mild/moderate inferior oblique muscle overaction, with or without diplopia. MethodWe retrospectively analysed data for the 12 patients who underwent the technique. Data were collected from October 2018 to September 2021. Surgery was performed by suturing the inferior oblique belly to the sclera at 5 mm posterior to the temporal end of the inferior rectus. All 12 patients had mild hypertropia (≤6 prism diopters [pd]) in primary position and mild/moderate inferior oblique overaction. Mean preoperative hypertropia was 4.42 pd ± 1.62. Diplopia was recorded in 10 cases. The diagnoses were fourth nerve paresis (9), unilateral primary inferior oblique overaction (2) and dissociated vertical deviation (1). Torticollis was observed in 7 cases, 2 had subjective torsion and 2 objective torsion. ResultsMean age was 46.86 ± 25.1 years (50%: men). Diplopia resolved in 9 of the 10 cases. The mean final vertical deviation was 1.5 ± 2.93 (p = 0.001) pd in straight gaze. Of 7 mild overshoot in adduction, it disappeared in 3 and 4 remained the same. Of 5 moderate overshoot in adduction, 2 improved to mild and 3 disappeared. Torticollis was eliminated in 5 patients and improved in another 2. Mean time from surgery was 14.08 ± 8.05 months. There were no overcorrections. ConclusionsInferior oblique muscle transposition with myopexy is a safe and effective procedure in patients with mild-to-moderate inferior oblique muscle overaction and small-angle hypertropia, with or without diplopia.

Transposición del vientre del oblicuo inferior sin desinserción en el tratamiento de la hipertropia en aducción

PurposeTo evaluate the efficacy and safety of inferior oblique muscle transposition and myopexy in patients with mild/moderate inferior oblique muscle overaction, with or without diplopia. MethodWe retrospectively analysed data for the 12 patients who underwent the technique. Data were collected from October 2018 to September 2021. Surgery was performed by suturing the inferior oblique belly to the sclera at 5mm posterior to the temporal end of the inferior rectus. All 12 patients had mild hypertropia (≤6 prism diopters [pd]) in primary position and mild/moderate inferior oblique overaction. Mean preoperative hypertropia was 4.42pd ±1.62. Diplopia was recorded in 10 cases. The diagnoses were fourth nerve paresis (9), unilateral primary inferior oblique overaction (2) and dissociated vertical deviation (1). Torticollis was observed in 7 cases, 2 had subjective torsion and 2 objective torsion. ResultsMean age was 46.86±25.1 years (50%: men). Diplopia resolved in 9 of the 10 cases. The mean final vertical deviation was 1.5±2.93 (P=.001) pd in straight gaze. Of 7 mild overshoot in adduction, it disappeared in 3 and 4 remained the same. Of 5 moderate overshoot in adduction, 2 improved to mild and 3 disappeared. Torticollis was eliminated in 5 patients and improved in another 2. Mean time from surgery was 14.08±8.05 months. There were no overcorrections. ConclusionsInferior oblique muscle transposition with myopexy is a safe and effective procedure in patients with mild-to-moderate inferior oblique muscle overaction and small-angle hypertropia, with or without diplopia.

The Role of Hypertropia in the Surgical Management of Bilateral Inferior Oblique Muscle Overaction

ABSTRACT Purpose Inferior oblique muscle overaction (IOOA) is an ocular motility anomaly consisting of overelevation in adduction, often associated with ipsilateral hypertropia. The weakening procedure of IO muscle is the most widely used procedure in IOOA. Usually, surgical planning is based on the degree of overaction of the IO muscle. Materials and Methods We have retrospectively analyzed patients with bilateral IOOA with and without hypertropia in primary position, who underwent a bilateral IO weakening procedure. Both the amount of IOOA and the presence of a hypertropia in primary position were taken into consideration for the surgical plan. Results Nineteen patients met the entry criteria for this study. In 12 patients, a hypertropia in primary position was present at baseline, and it was significantly lower after the asymmetrical IO weakening: 11 had an asymmetric IOOA at baseline, and one had symmetric IOOA. None of the remaining seven patients had a vertical deviation in primary position before surgery, despite having asymmetric IOOA. None of them developed a hypertropia in primary position after symmetric IO weakening. Conclusions Our findings outline the utility of considering both the presence of a vertical deviation in primary position and the magnitude of IOOA in this set of patients. Asymmetric inferior oblique weakening procedure is effective in treating a hypertropia in the primary position and bilateral IOOA.

Botulinum Toxin Injection of the Inferior Oblique Muscles for V-Pattern Strabismus and Primary Position Hypertropia

To evaluate outcomes of botulinum toxin (BTX) injection of the inferior oblique (IO) muscle. Retrospective case series. Setting: Single center, ophthalmology department at Boston Children's Hospital. All patients treated with IO muscle injection of BTX (onabotulinumtoxinA) between 2010 and 2020. Sensorimotor evaluations at short-term (<2 months), medium-term (2-4 months), and long-term (≥4 months) intervals. Primary outcomes included median improvement in V-pattern strabismus and primary position hypertropia. Secondary outcomes included IO muscle overaction. Wilcoxon signed-rank tests were performed to identify differences before and after injection. Record review identified 20 patients with a median age of 4.5 (range, 1-69) years. Median BTX dose injected (31 IO muscles) was 5.0 (range, 3.0-7.0) units. Indications included V-pattern strabismus (N=8), hypertropia (N=7), or both (N=5). Median long-term interval was 6.4 (range, 4.1-26.6) months. Injections were concurrent with treatment of horizontal strabismus in all but 3 cases. Median V-pattern magnitude changed from 10 prism diopters (PD) preoperatively to 0 PD short-term (P=.006) and 3.5 PD long-term (P=.34). Median hypertropia changed from 8.5 PD preoperatively to 1.5 PD short-term (P=.01) and 8 PD long-term (P=.87). Median IO muscle overaction grade improved significantly at short-term (P < .001) and long-term (P=.007) intervals. There were no complications associated with the IO muscle injections. BTX injection of the IO muscles can be a useful adjunct to the management of V-pattern strabismus. Intervention for primary position hypertropia may be helpful for short-term relief with no expectation of long-term benefit.

Inferior oblique muscle belly transposition and myopexy for diplopia

ABSTRACT To evaluate the outcomes of and review the indications for Inferior oblique muscle belly transposition in adults with diplopia and small-angle hypertropia associated with mild or moderate upshoot in adduction. We retrospectively analyzed data for the six patients who underwent the technique. Surgery was performed by suturing the inferior oblique belly to the sclera at 5 mm posterior to the temporal pole of the inferior rectus. Data were collected from October 2018 to April 2020. All six patients had diplopia and mild hypertropia (≤6 prism diopters [pd]) in primary position. Mean preoperative hypertropia was 4.17 pd (range, 2–6 pd). Mean age was 51 ± 28.71 years. The diagnoses were fourth nerve paresis (5) and dissociated vertical deviation (1). All patients had mild/moderate upshoot in adduction. Torticollis was observed in four cases. Diplopia resolved in 5 of the 6 cases. The mean final vertical deviation was 2 pd in straight gaze. Torticollis was eliminated in 2 patients and improved in another 2. The upshoot in adduction was totally eliminated in the six patients. Transitory mild limitation of elevation in adduction was observed in two patients during the first week after surgery. No ocular torsion was diagnosed after surgery. Mean time from surgery was 11.5 months. No overcorrections were recorded. Inferior oblique muscle belly transposition with myopexy is a good alternative procedure in patients with diplopia associated with mild-to-moderate upshoot in adduction and small-angle hypertropia.

Inferior Oblique Recession with 5 mm Loop to Correct Vertical Deviation and Inferior Oblique Overaction Secondary to Superior Oblique Palsy

ABSTRACT Purpose: To evaluate the effect of augmented inferior oblique recession (recession +5 mm loop) on the vertical deviation in primary position (PP) and the inferior oblique overaction (IOOA) in patients with unilateral congenital or acquired superior oblique palsy. Patients and methods: The medical records of patients who underwent unilateral inferior oblique recession with 5 mm loop during 2012 and 2019 were retrospectively reviewed. All patients had small to moderate manifest or intermittent hypertropia in PP and overaction of the inferior oblique muscle of +2 or +3 in lateral gaze. Patients who had combined inferior rectus surgery of the contralateral eye or who had previous vertical muscle surgery were excluded. Results: A total of 26 patients were included. Of these, three patients had combined horizontal muscle surgery. In 22 patients, the superior oblique palsy was congenital or longstanding, in 4 it was acquired and stable for more than 9 months. The mean preoperative vertical deviation in PP at distance and near was 14.7Δ and 11.2Δ, respectively. The mean postoperative vertical deviation was 5.7Δ and 4.1Δ after a mean follow-up of 19 months. The IOOA improved in all patients, 16 patients had an improvement of +2 and 10 patients had an improvement of +1. Conclusion: Inferior oblique recession with a 5 mm loop is a simple and quick technique to correct small to moderate hypertropia in primary position and inferior oblique overaction in contralateral gaze in patients with congenital, longstanding or acquired superior oblique palsy without risk of overcorrection.

Stepped Strabismus Surgery.

PurposeTo present stepped strabismus surgery as a novel technique in cases of small to moderate angle strabismus.MethodsRetrospective chart review of cases of stepped strabismus surgery from 2010 untill 2018. In stepped surgery, the first muscle is operated on under rapid induction-recovery IV propofol infusion. Patient is assessed in the OR. If deemed necessary, other muscles are operated on under general anesthesia. No adjustable sutures are used.ResultsThe technique was used in 22 cases of superior oblique palsy (SOP) (primary position hypertropia in the range of 12–25 prism diopters) and 29 horizontal strabismus cases (angles in the range 12–20 prism diopters). The first step was an inferior oblique myectomy in the SOP cases and a single rectus recession in the horizontal cases. After intraoperative assessment, 31% (16/51) needed additional muscle surgery. After 6 months of follow up, the overall reoperation rate was 9%. The technique was well tolerated by all patients.ConclusionStepped strabismus surgery is a useful technique for small to moderate angle strabismus cases with the potential for reducing the number of extraocular muscles operated on without compromising the surgical outcome.

Inferior oblique recession associated to partial temporal inferior rectus recession in unilateral congenital superior oblique palsy.

To evaluate the effectiveness of inferior oblique recession with contralateral partial temporal inferior rectus recession in patients with decompensated congenital unilateral superior oblique palsy (SOP) in correcting moderate vertical deviations in primary position. The medical records of patients with SOP who underwent inferior oblique recession with contralateral partial temporal inferior rectus recession were reviewed retrospectively. Vertical deviation in primary position, subjective torsion, diplopia, residual deviation, and the deviation decrease were evaluated. Four patients (three males and one female, age range 29-56 years) with congenital unilateral SOP and mean vertical deviation of 21.0 ± 5.3PD (range 14-25D) in primary position were included. Mean correction of hypertropia in primary position with this technique was 15.5 ± 5.3PD (range 10-20PD). The mean hypertropia on gaze to the contralateral side changed from 30.0 ± 10.8D before surgery to 9.3 ± 7.9D after surgery. Torsion had a mean change of 4.8° of incyclodeviation. Preoperatively, all patients had head tilt and diplopia, which was resolved in all but one patient, who will need surgery. Patients were followed an average of 18 months. No adverse events were reported in any subjects. When performing recession of inferior oblique muscles in SOP associated to a full recession of the contralateral inferior rectus, there is a risk of overcorrection in those with moderate angles. Performing a partial recession in the contralateral inferior rectus eye corrected up to 20PD in primary position in our series, reducing this risk.

Efficacy of isolated inferior oblique anteriorization on large-angle hypertropia associated with unilateral superior oblique palsy

To evaluate the results of inferior oblique anteriorization for the treatment of large-angle hypertropia secondary to superior oblique palsy and to determine predictors of success and the occurrence of antielevation syndrome. In this prospective study, 25 patients with unilateral congenital and acquired superior oblique palsy who had a primary position hypertropia of at least 25Δ underwent inferior oblique anteriorization in the paretic eye. Postoperative changes in vertical deviation of primary position and contralateral gaze, abnormal head posture, extorsion, associated horizontal deviation, inferior oblique overaction, superior oblique underaction, and elevation in abduction were examined. Surgical success was defined as residual hypertropia in primary position of ≤4Δ at final examination. The mean age of patients at surgery was 19.8±11.9years (range, 4-49). The mean preoperative deviation in the primary position was 27.6Δ ± 3.2Δ; in contralateral gaze, 35.0Δ ± 3.8Δ; these measurements decreased postoperatively to 4.7Δ ± 5.6Δ and 7.0Δ ± 5.5Δ, respectively, after a median follow-up of 8months. The success rate was 72%, with no difference between patients with a preoperative deviation of 25Δ-29Δ and those with deviation of 30Δ-35Δ. In a multivariate logistic regression, preoperative extorsion was negatively related to success (OR=8.01; P=0.03). At the final follow-up, 4 patients (16%) showed antielevation syndrome and were clinically asymptomatic. In unilateral superior oblique palsy, one-muscle surgery, including inferior oblique anteriorization, can be conducted to resolve large-angle hypertropia of >25Δ. Excyotorsion is a risk factor that increases the likelihood of failure.

Single-stage superior oblique tendon recession with suture adjustment under topical anesthesia and sedation for A-pattern strabismus with superior oblique overaction

To assess the surgical effect of single-stage superior oblique recession with intraoperative suture adjustment under topical anesthesia and sedation in terms of A-pattern correction, vertical alignment, and superior oblique overaction. The medical records of patients who underwent superior oblique weakening (recession with adjustable suture) for superior oblique overaction from 2015 to 2018 were reviewed retrospectively. Preoperative, pre- and postadjustment, and 6-week follow-up data were assessed and compared for A pattern, primary position hypertropia, superior oblique overaction scale and objective fundus torsion. A total of 29 patients (17-42years of age) were included. Of 51 operated eyes, 37 underwent intraoperative adjustment (further recession of 1-4mm) after superior oblique recession of 8mm. Mean decrease in primary position hyperdeviation after adjustment was 3.6Δ ± 2.7Δ (range, 0Δ-8Δ); in A-pattern deviation, 5.5Δ±4.8Δ (range, 0Δ-16Δ). At 6weeks' follow-up, A pattern had either resolved completely or became clinically insignificant (<10Δ) in 23 of 29 patients (79%); 24 (83%) patients had hyperdeviation in primary position of ≤5Δ. Of the 5 patients with preoperative primary position hyperdeviation of 15Δ-30Δ, 2 had residual primary position hyperdeviation of >10Δ. In our study cohort, single-stage, unilateral superior oblique tendon recession with adjustable suture under topical anesthesia and sedation was well tolerated and resulted in good postoperative outcomes at 6weeks' follow-up, effectively correcting primary position vertical deviation of <15Δ.

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.

Comparison of different tendon transposition techniques for the treatment of monocular elevation deficiency type 2

To compare results of three different tendon transposition techniques (Knapp procedure and two modified techniques) for the treatment of type 2 monocular elevation deficiency (MED) patients. The medical records of patients with MED type 2 operated on at a single institution from 2000 to 2016 were reviewed retrospectively. Patients were divided into three vertical transposition groups: (1) full tendon width, (2) augmented surgery; and (3) partial tendon width. Surgical success was defined as no severe limitation of upgaze, hypotropia of <6Δ, and no hypertropia in primary position. Pre- and postoperative vertical deviations in the primary position and limitations in elevation levels were compared. A total of 39 patients were included. The pre- and postoperative deviations in the full-tendon group were 22.50Δ ± 4.17Δ and 3.50Δ ± 1.27Δ, respectively; in the augmented surgery group, 23.75Δ ± 4.78Δ and 1.75Δ ± 1.14Δ; and in the partial-tendon group, 20.50Δ ± 3.98Δ and 4.12Δ ± 2.78Δ. Corrected vertical deviations were 19Δ, 23Δ, and 16Δ, respectively. The pre- and postoperative limitation of elevations were -2.80 and -0.80 in the full-tendon group, -3.20 and -0.90 in the augmented surgery group, and -2.37 and -1.12 in the partial-tendon group. The pre- and postoperative vertical deviation improvements and limitations of elevation were statistically significant (P<0.05) in all groups. Success was achieved in 29 patients (74%). In this study cohort, all three procedures were reasonably effective in improving vertical deviations and limitation of elevation.

Inferior oblique belly transposition for V pattern strabismus

ABSTRACT Purpose Monocular transposition of the inferior oblique muscle belly (IOMBT) effectively weakened mild to moderate inferior oblique overaction and corrected small primary position hypertropia. Now we aim to evaluate the efficacy of inferior oblique muscle belly transposition (IOMBT) in treating V pattern strabismus with upshoot in adduction. Methods This is a retrospective review of 13 patients with V pattern who underwent IOMBT procedure from January 2017 to December 2018. The inclusion criteria were: the amount of V pattern from 15 to 25 pd; the degree of upshoot in adduction from +1 to +3; no or trace vertical deviation in primary gaze position. Bilateral IOMBT was performed to reduce the V pattern. Horizontal rectus muscle surgery was performed at the same stage to correct the horizontal deviation. The angle of deviation in upgaze and downgaze was measured pre- and postoperatively. The degree of elevation in adduction was graded. The amount of V pattern was the difference in horizontal angle between up- and downgaze. The change in the amount of V pattern was assessed postoperatively. Results All 13 patients had complete resolution of the V pattern. The amount of V pattern changed from 18.92 ± 4.310 prism diopters to 3.462 ± 1.854 prism diopters postoperatively. The mean grade of upshoot in adduction changed from 1.92 to 0.12 postoperatively. No depression in adduction or consecutive A pattern were found after surgery. Conclusions IOMBT can successfully eliminate the V pattern in patients with mild V pattern esotropia or exotropia with mild to moderate upshoot in adduction. This procedure appears to be a useful addition to our inferior oblique surgical armamentarium.

Дозированное хирургическое лечение вертикального косоглазия с применением методики передней транспозиции нижней косой мышцы

«Российская офтальмология онлайн» - электронное информационное издание, создается с 1 марта 2010 года под эгидой Российского общества офтальмологов. Основная задача проекта - научно-информационная поддержка специалистов в области офтальмологии.

Stepped strabismus surgery

Purpose To present stepped strabismus surgery as a novel technique in cases of small to moderate angle strabismus. Methods Retrospective chart review of cases of stepped strabismus surgery from 2010 untill 2018. In stepped surgery, the first muscle is operated on under rapid induction-recovery IV propofol infusion. Patient is assessed in the OR. If deemed necessary, other muscles are operated on under general anesthesia. No adjustable sutures are used. Results The technique was used in 22 cases of superior oblique palsy (SOP) (primary position hypertropia in the range of 12-25 prism diopters) and 29 horizontal strabismus cases (angles in the range 12-20 prism diopters). The first step was an inferior oblique myectomy in the SOP cases and a single rectus recession in the horizontal cases. After intraoperative assessment, 31% (16/51) needed additional muscle surgery. After 6 months of follow up, the overall reoperation rate was 9%. The technique was well tolerated by all patients. Conclusion Stepped strabismus surgery is a useful technique for small to moderate angle strabismus cases with the potential for reducing the number of extraocular muscles operated on without compromising the surgical outcome.

Outcome of inferior oblique disinsertion versus myectomy in the surgical treatment of unilateral congenital superior oblique palsy

To compare the outcome of inferior oblique disinsertion and myectomy in patients with unilateral congenital superior oblique palsy. In this prospective study, consecutive patients with superior oblique palsy underwent either myectomy or disinsertion of the inferior oblique muscle. Success was defined as postoperative hypertropia of ≤5Δ in primary position and no hypotropia. In cases with preoperative hypertropia of ≤5Δ, success was defined as improved hypertropia and resolution of abnormal head position (AHP). A total of 62 patients were included: 34 underwent myectomy; 28, disinsertion. Preoperative primary position hypertropia was 15.8Δ ± 7.4Δ in the myectomy group and 14.5Δ ± 7.3Δ in the disinsertion (P=0.756). AHP was present in 85.3% and 85.7% of patients, respectively (P=1). Mean follow-up was in the myectomy group 7.5±6.7months and 6.9±3.0months in the disinsertion group (P=0.637). Correction of hypertropia in primary position was more pronounced in the myectomy group (14.3Δ±7.4Δ vs 10.0Δ±5.4Δ; P=0.013). Success was achieved in 91.2% of myectomy and 60.7% of disinsertion patients (P=0.006). Persistence of AHP did not differ between groups (8.8% in the myectomy group vs 7.1% in the disinsertion group [P=1]). Comparison of patients with preoperative hypertropia of ≤15Δ revealed nonsignificant differences between groups in rate of success (100% vs 81.3% [P=0.226]) and correction of primary position hypertropia (8.8Δ±3.2Δ vs 7.6Δ±4.0Δ [P=0.336]). In our study cohort, inferior oblique myectomy had a greater effect in reduction of primary position hypertropia; however, disinsertion proved as effective as myectomy if preoperative vertical deviation was ≤15Δ. Both procedures effectively corrected AHP and demonstrated self-adjustment.

Surgical Outcome of Single Inferior Oblique Myectomy in Small and Large Hypertropia of Unilateral Superior Oblique Palsy.

To determine the efficacy of isolated inferior oblique myectomy on hypertropia in primary position, side gazes, and tilts, and its effect on comitancy and abnormal head posture in unilateral superior oblique palsy. Thirty-nine patients with unilateral superior oblique palsy who had inferior oblique overaction underwent inferior oblique myectomy. The hypertropia was measured in primary position, side gazes, and tilts preoperatively and postoperatively. Abnormal head posture was also assessed. Success was defined as primary position hypertropia of 5 prism diopters (PD) or less. The mean distance hypertropia was 15.7 ± 7.7 PD (range: 3 to 30 PD) preoperatively and 1.5 ± 3.3 PD (range: 0 to 16 PD) postoperatively (P < .001). The mean reduction of distance hypertropia postoperatively was 14.2 ± 7.8 PD (range: 3 to 30 PD). The contralateral gaze hypertropia decreased from 21.7 ± 9.0 PD (range: 5 to 45 PD) preoperatively to 3.6 ± 5.1 PD postoperatively (range: 0 to 20 PD) and ipsilateral head tilt hypertropia decreased from 21.9 ± 8.4 PD (range: 8 to 40 PD) preoperatively to 5.0 ± 5.9 PD (range: 0 to 24 PD) postoperatively (P < .000 for both). Incomitance (contralateralipsilateral gaze hypertropia) decreased from 15.0 ± 7.4 PD (range: 3 to 35 PD) preoperatively to 2.8 ± 4.1 PD (range: 0 to 16 PD) postoperatively (P < .001). The success rate between the two groups of patients who had hypertropia of 15 PD or less and greater than 15 PD in primary position was not statistically different (94.7% vs 85%). Two patients underwent a second operation for residual hypertropia. There was no overcorrection. Thirty-two patients had abnormal head posture, which resolved postoperatively in 29 cases. Isolated inferior oblique myectomy is an effective procedure in resolving hypertropia up to 30 PD due to unilateral superior oblique palsy, with a minimal risk of overcorrection and low risk of undercorrection. It decreases incomitancy, is a self-titrating procedure, and resolves abnormal head posture efficiently. [J Pediatr Ophthalmol Strabismus. 2019;56(1):23-27.].

Consecutive superior oblique palsy after adjustable suture spacer surgery for Brown syndrome: incidence and predicting risk

To determine the incidence of and to identify characteristics predicting significant superior oblique palsy (SOP) after adjustable superior oblique suture spacer surgery for treatment of Brown syndrome. The medical records of patients treated for unilateral Brown syndrome with adjustable suture spacers (2005-2016) were reviewed to identify possible association of age at surgery, spacer length, surgeon performing procedure, severity of Brown syndrome, preoperative hypotropia in primary position and affected side gaze, and reduction in Brown restriction on postoperative superior oblique function. "Good" postoperative superior oblique function was defined as absence of hypertropia and diplopia in primary position and no more than intermittent diplopia in downgaze comfortably fused with ≤4Δ base-down or head tilt of <10°. Presence of postoperative hypertropia in primary position with increase in downgaze met criteria for significant SOP. Postoperative Brown restriction of≤-2 indicated resolution of Brown syndrome. Median age at surgery was 59months, interquartile range (IQR) was 32-82months, and median spacer length was 6mm (range, 2-7mm) for 19 included patients. Preoperative median hypotropia was 9Δ (IQR, 0Δ-12Δ) in primary position and 18Δ (IQR, 5Δ-22Δ) in affected side gaze. Of 19 patients, 16 (84%) achieved sufficient resolution of Brown syndrome, but 6 (32%) developed significant SOP. Modest preoperative hypotropia in affected side gaze was the only predictor of significant SOP (likelihood ratio test=7.11; P=0.008). Logistic regression modeling enabled estimation of risk of significant SOP based on preoperative side gaze hypotropia. Suture spacer surgery can result in significant SOP. Risk may be predicted by magnitude of preoperative side gaze hypotropia.