Comparison of head tilt test between sagging eye syndrome and acquired unilateral trochlear nerve palsy.

PURPOSE: To investigate the distinction between sagging eye syndrome (SES group) and acquired unilateral trochlear nerve palsy (Trochlear group) in the Bielschowsky head tilt test (BHTT). METHODS: Fifteen patients in the SES group (mean age 74.6 ± 5.2 years) and 14 patients in the Trochlear group (55.2 ± 15.9 years) visited the Department of Ophthalmology, Hyogo Medical University Hospital between November 2016 and October 2022 for treatment of their diplopia. Eye position was measured with the alternate prism cover test, and values for fixation of the dominant eye, or unaffected eye, were used. Cyclodeviation was measured with the synoptophore and the Glaucoma Module Premium Edition of the SPECTRALIS optical coherence tomography. In the BHTT, eye position was measured in three head postures: primary position (PP), head tilt to the side with hypertropia (Hyper), and head tilt to the side with hypotropia (Hypo). The differences in vertical deviation between PP and Hyper (Hyper - PP), PP and Hypo (PP - Hypo) and Hyper - Hypo were measured and compared. RESULTS: Vertical deviation in primary position was 7.3 ± 4.5 PD in the SES group and significantly larger (17.1 ± 8.4 PD) in the Trochlear group (p = 0.002). The vertical deviation in Hyper was significantly larger in the Trochlear group with 7.7 ± 4.7 PD and 22.1 ± 9.4 PD, respectively (p < 0.001), whereas the that in Hypo was not significantly different between the two groups with 6.5 ± 3.4 PD and 8.4 ± 6.6 PD, respectively (p = 0.725). The SES group showed no significant difference according to the 3 head postures (p = 0.311), while the Trochlear group showed a significantly different with smaller mean values in vertical deviation in Hypo (p < 0.001). The difference in the vertical deviation for the 3 head postures was the largest in Hyper - Hypo (1.7 ± 2.1 PD and 13.6 ± 7.1 PD, respectively), and the accuracy of SES was at the cutoff value of 6 PD, and it was considered not to be SES if the value was 6PD or higher. The accuracy of SES determination was 100% sensitivity and 100% specificity, and the area under the curve was 1.0. CONCLUSION: The difference in Hyper - Hypo in the BHTT may be the most useful index in differentiating SES from acquired unilateral trochlear nerve palsy; if the difference was more than 6 PD, the probability of SES was very low.

Clinical characteristics and surgical outcomes in patients with superior oblique muscle palsy: a retrospective study on 1057 patients.

BACKGROUND: To evaluate the clinical findings of patients with SOP who underwent surgery. METHODS: This historical cohort study was performed on 1057 SOP patients managed with surgery in Farabi Hospital, Iran, from 2011 to 2022. RESULTS: There were 990 (93.7%) patients with unilateral SOP with the mean age of 21.8 ± 14.8 years. Of these, 715 patients (72.2%) were diagnosed with congenital SOP, and 275 patients (27.8%) had acquired SOP (P < 0.001). In contrast, 67 (6.3%) patients were diagnosed with bilateral SOP, with the mean age of 19.4 ± 15.6 years. Among these, 18 cases exhibited the masked type. The mean angle of vertical deviation in primary position at far in unilateral and bilateral cases was 15.6 ± 8.3 and 13.3 ± 9.1 △, respectively (P < 0.001). In unilateral cases, abnormal head posture (AHP) was detected in 847 (85.5%) patients and 12 (1.2%) had paradoxical AHP. Amblyopia was found in 89 (9.9%) unilateral and 7 (10.3%) bilateral cases. Solitary inferior oblique myectomy, was the most common surgery in both unilateral (n = 756, 77.1%) and bilateral (n = 35, 52.2%) patients. The second surgery was performed for 84 (8.6%) unilateral and 33 (49.3%) bilateral cases (P < 0.001). The prevalence of amblyopia and the mean angle of horizontal deviation were significantly higher in patients who needed more than one surgery (all P < 0.05). CONCLUSION: Congenital SOP was more than twice as frequent as acquired SOP and about 90% of unilateral and 50% of bilateral cases were managed with one surgery. Amblyopia and significant horizontal deviation were the most important factors for reoperation. TRIAL REGISTRATION: The Institutional Review Board approval was obtained from the Tehran University of Medical Sciences (IR.TUMS.FNM.REC.1400.012) and this study adhered to the tenets of the Declaration of Helsinki and HIPAA.

Surgical treatment of unilateral acquired superior oblique muscle palsy in adults by inferior oblique belly transposition: a retrospective analysis.

PURPOSE: Evaluate and analyze the efficacy of inferior oblique belly transposition (IOBT) in treating adult patients with diplopia and small-angle hypertropia caused by mild to moderate inferior oblique overaction (IOOA) secondary to acquired superior oblique palsy (SOP). METHODS: Nine adult patients with diplopia and small-angle hypertropia associated with mild to moderate IOOA secondary to unilateral acquired SOP were included in the current retrospective study. All patients received the IOBT procedure between February 2019 and May 2023 at The Second People's Hospital of Jinan and were followed up for more than 6 months after the surgery. During the procedure, the belly of the inferior oblique muscle was fixed to the sclera at 5 mm posterior to the temporal insertion of the inferior rectus muscle. The following indicators were reviewed pre- and post-surgery: the vertical deviation (VD) in the primary position and in the Bielschowsky test, the fovea disc angle (FDA) of the affected eye, changes in IOOA, and diplopia. RESULTS: After IOBT, the VD in the primary position decreased from 7.22△ ± 1.72△ (range 4△-10△) to 1.22△ ± 1.30△ (range 0△-3△). The VD in the Bielschowsky test decreased from 13.00△ ± 1.80△ to 3.22△ ± 1.09△. The FDA decreased from 10.02° ± 3.34° to 6.26° ± 1.91°. The grade of IOOA was reduced from 2.00 (1.00, 2.00) to 0.00 (0.00, 1.00). All changes were statistically significant (P < 0.001 or P = 0.006). Diplopia was resolved completely for all patients. CONCLUSIONS: IOBT can effectively treat adults with diplopia and small-angle hypertropia caused by mild to moderate IOOA secondary to acquired SOP.

Disinsertion-distal myectomy and tucking of inferior oblique combined with superior oblique full tendon advancement in superior oblique palsy.

PURPOSE: To assess the preliminary outcomes of inferior oblique (IO) disinsertion-distal myectomy and tucking combined with superior oblique (SO) full tendon advancement in patients with Knapp II or III superior oblique palsy. METHODS: This single-centered retrospective study included 16 eyes from 13 patients with Knapp Class II or III SO palsy. All patients underwent IO disinsertion-distal myectomy and tucking combined with SO full tendon advancement while under general anesthesia. Pre- and post-operative levels of vertical deviation in the primary position, abnormal head position, IO hyperfunction and SO hypofunction, torsion, as well as the presence of diplopia, were all measured, and the differences were statistically compared. RESULTS: Pre-operatively, 12 patients had abnormal head positions, and two had diplopia. The pre-and post-operative levels of IO hyperfunction and SO hypofunction, as well as a vertical deviation in the primary position and torsion, all differed statistically significantly (p < 0.01). CONCLUSIONS: Inferior oblique disinsertion distal myectomy and tucking combined with SO full tendon advancement surgery appears to be an effective procedure in patients with congenital and acquired Knapp Class II or III SO palsy.

Clinical features of excyclotorsion in the non-paretic eye of patients with congenital unilateral superior oblique palsy.

BACKGROUND: To investigate preoperative clinical features and postoperative results according to the correspondence between excyclotorsion and the paretic eye in patients with congenital unilateral superior oblique palsy (USOP). METHODS: A retrospective review of medical charts was performed. The patients were divided into the accordance (ocular excyclotorsion in the paretic eye) and disaccordance (ocular excyclotorsion in the non-paretic eye) groups. The degree of excyclotorsion (scale, 0-4) was measured. Age, sex, hypertropia at the primary position, fixation preference, inferior oblique overaction, and degree of excyclotorsion were measured. RESULTS: Ninety-eight patients were included in this study. There were 70 (71.4%) and 28 patients (28.6%) in the accordance and disaccordance groups. Sixteen patients (22.9%) in the accordance group and 12 patients (42.9%) in the disaccordance group were aged under 2 years (p = 0.04). A fixation preference of the paretic eye was observed in 2 (2.9%) and 8 (28.6%) patients in the accordance and disaccordance groups (p < 0.01). The postoperative degree of excyclotorsion in the accordance group (0.14 ± 0.39) was lower than that in the disaccordance group (0.28 ± 0.71) (p = 0.01). The residual postoperative excyclotorsion (> 1) were observed in the disaccordance group (14 patients, 50%) and accordance group (16 patients, 22.9%) (p = 0.01). CONCLUSION: Preoperative disaccordance between excyclotorsion and the paretic eye was observed in patients who were under 2 years of age and preferred fixation of the paretic eye. The postoperative degree of excyclotorsion was lower in the accordance group.

Trochleaectomy: An Effective Treatment of Trochlear Pain in Monocular Patients.

BACKGROUND: Conventional treatment options for trochlear pain arising from trochleitis or primary trochlear headache include oral anti-inflammatory medications and/or local injection of corticosteroids and local anesthetic. Trochleaectomy is an additional option to consider for monocular patients with intractable trochlear pain. METHODS: We report 3 patients undergoing trochleaectomy for refractory trochlear pain syndromes. RESULTS: Trochleaectomy resulted in resolution of their periocular discomfort. CONCLUSIONS: Trochleaectomy is an effective procedure to treat trochlear pain syndrome in functionally monocular patients.

[Inferior Rectus Myopexy: Indications and Long-Term Results]. / Myopexie des Musculus rectus inferior: Indikationen und Langzeitergebnisse.

PURPOSE: The rectus inferior myopexy is often used in vertical incomitant deviations without significant deviation in primary position. We analysed the long-term results in different pathologies. METHODS: Retrospective study of patients operated on rectus inferior myopexy between 1984 and 2018. Vertical and torsional deviations were measured in primary position (PP) and 25° downgaze and the field of binocular single vision (FBSV) was evaluated with the Harms tangent screen, establishing a functional score. Postoperative follow-ups took place at 1 month, 6 months and long term (1 - 24 years). RESULTS: 62 patients were included (mean age 41 years, 28 women and 34 men). 47 presented a fourth nerve palsy (group 1) and 15 a reduced depression of other origins (group 2). 31 patients had undergone previous operations and 34 contemporaneous operations with the myopexy. In group 1, preoperative mean vertical deviation was 6.4° in PP and 12.3° on downgaze, postoperative 4° and 7.2°. In group 2, the value decreased from 3.3° in PP and 11.5° on downgaze to 1.2° and 6.6°. Over the years, there has been a decrease in the effect, particularly in group 1. The torsion was hardly influenced in both groups. The median functional score of FBSV improved in group 1 from 10% preoperatively to 39% postoperatively and in group 2 from 25 to 69%. CONCLUSION: The inferior rectus myopexy shows an effective way to reduce the incomitance of vertical deviation without significant influence on torsion. Over the years, there has been a decrease in the effect, particularly in patients with superior oblique paresis. We do not consider inferior rectus myopexy as a classic surgical treatment of superior oblique paresis. We have only used it in special cases.

Recurrent Superior Oblique Myokymia Treated by Distal Tendon Extirpation.

BACKGROUND: We describe successful surgical treatment of superior oblique myokymia, which had recurred after superior oblique tenectomy. METHODS: Single case report. RESULTS: The distal stump of the superior oblique tendon was extirpated by stripping it from the globe. The ipsilateral superior rectus muscle also was recessed, to correct a hypertropia that had resulted from the original superior oblique tenectomy. CONCLUSIONS: Complete removal of the distal superior oblique muscle tendon provided definitive relief of superior oblique myokymia. Superior rectus muscle recession, combined with previous inferior oblique myectomy, compensated effectively for loss of superior oblique function.

Rapidly Growing and Asymptomatic Skull Base Lesion.

Trochlear schwannomas typically present with diplopia and are extremely rare benign intracranial neoplasms that require the combined expertise of neurotologists and neurosurgeons for surgical excision. A combined petrosal approach offers a surgical route for removal of growing and/or symptomatic tumors. A study of a trochlear nerve schwannoma that demonstrated rapid growth but was otherwise asymptomatic was presented in this study.

Predictive factors for corrective effect of inferior rectus recession for congenital superior oblique palsy.

PURPOSE: To identify preoperative factors associated with the surgical corrective effect of contralateral inferior rectus recession (IRR) for vertical deviation in patients with congenital superior oblique palsy (SOP). METHODS: This retrospective study included 20 treatment-naïve patients with unilateral congenital SOP (age range, 6-79 years) who underwent contralateral IRR according to our basic policy to select IRR for paretic eye fixation. The corrective effect (°/mm) of IRR was defined as the difference in the vertical deviation at the primary gaze position between before and 6-18 months after surgery per distance of recession. We also measured the preoperative vertical deviation at primary and secondary gaze positions, and vertical deviation with head-tilting, and calculated the difference in vertical deviation between these positions. We analyzed the correlation between the corrective effect of IRR and these study parameters. RESULTS: The mean corrective effect of IRR was 2.4 ± 1.6°/mm, which had a significant correlation with preoperative differences in vertical deviation between the primary gaze position and the downward (P = 0.004, r = -0.61) and contralateral gaze positions (P = 0.03, r = -0.48); and the presence of preoperative stereopsis (P = 0.02, r = -0.51). After excluding a statistical outlier, the correlation between the corrective effect and the difference between the primary and contralateral gaze positions was no longer significant (P = 0.07), while the other two relationships remained significant. CONCLUSIONS: Our findings suggest that preoperative differences in vertical deviation between the primary and downward gaze positions and the presence of preoperative stereopsis are important considerations prior to performing IRR for congenital SOP, particularly with paretic eye fixation.

[Isolated Unilateral Strabismus Sursoadductorius (Congenital Trochlear Palsy) with and without Hypotrophia of the Superior Oblique Muscle-Orthoptic Differences in Adulthood]. / Unilateraler dekompensierender Strabismus sursoadductorius mit und ohne Hypotrophie des M. obliquus superior ­ orthoptische Unterscheidungsmerkmale im Erwachsenenalter.

PURPOSE: The clinical feature of unilateral decompensating strabismus sursoadductorius (dSSA; often called congenital superior oblique palsy, CSOP) is not an etiologically uniform entity. Hypotrophy of the superior oblique muscle (HMOS) is a frequent and immediate cause of dSSA/CSOP. In this study, clinical characteristics of dSSA/CSOP with and without HMOS are compared. PATIENTS AND METHODS: Twenty-five consecutive patients (age 14 - 69 years; median 43 years) were included in this study, 14 with 3T MRI-proven HMOS (group 1) and 11 without HMOS (group 2). HMOS was defined as a reduction of the medio-lateral (ML) as well as based on ML and cranio-caudal (CC) diameter calculated area = (ML · CC/4) · π of the affected superior oblique muscle (SOM) < 80% in comparison to the contralateral SOM (measured on the single coronal image on which the muscle has its greatest extent). The two groups were compared in terms of head tilt, cyclo- and vertical deviation and the Bielschowsky head tilt test. Patients were classified according the Knapp's classification. RESULTS: Both the incidence of head tilt with 14/14 vs. 5/11 (χ2 = 0.003) and its degree: 11.1 ± 4.5° vs. 3.2 ± 4.1° (p < 0.001) was higher in group 1 than in group 2, as well as the Bielschowsky head tilt test: 9.3 ± 4.3° vs. 3.8 ± 4.9° (p = 0.008). The average amount of hypertropia was larger in group 1 than in group 2 during adduction: 16.7 ± 5.3° vs. 9.3 ± 3.4° (p < 0.001) as well as during adduction and downgaze of the affected eye: 14.6 ± 7.1 vs. 7.2 ± 3.7° (p = 0.03). In the sagittal plane, the increase of vertical deviation was larger in group 1 than in group 2: 2.8 ± 7.8 vs. - 2.4 ± 4.2 (p = 0.04); the excyclodeviation was larger in group 1 in all three planes (sagittal plane, adduction and abduction) in comparison to group 2: 1.3 ± 4.1 vs. - 2.9 ± 2.8 (p = 0.006), 2.4 ± 5.2 vs. - 2.2 ± 2.9 (p = 0.01), 0.5 ± 3.8 vs. - 2.7 ± 3.9 (p = 0.05). Knapp's class II was found in 6 of 15 patients in group 1 and only in this patient group (χ2 = 0.03). CONCLUSIONS: In both groups, the vertical deviation showed a great dispersion. In patients without HMOS (group 2), vertical deviation in adduction did not exceed 15°. Patients with HMOS (group 1) do not show the typical features of a later acquired trochlear palsy due to an early developed compensating innervation. A vertical deviation in adduction of more than 15°, increasing excyclodeviation towards downgaze in all three planes (sagittal plane, adduction and abduction) and Knapp's class II are relatively reliable predictors of a hypoplasia of the SOM. An internationally uniform term for this group of patients, such as superior oblique weakness or superior oblique hypotrophy, would be desirable.

The influence of ocular sighting dominance on Fundus torsion in patients with unilateral congenital superior oblique palsy.

PURPOSE: The purpose of our study was to determine whether ocular sighting dominance may influence the ocular torsion in patients with unilateral congenital superior oblique palsy (UCSOP). METHODS: This retrospective study included 22 UCSOP patients with radiologic evidence of unilateral superior oblique muscle hypoplasia on orbital magnetic resonance imaging and 66 healthy individuals with normal ocular motility as controls. Ocular torsion was assessed both quantitatively and qualitatively using digital fundus photography. The disc-fovea angle (DFA) was measured quantitatively using image software on a computer screen. All fundus photographs were qualitatively graded as normal torsion, extorsion, or intorsion in all subjects, based on the location of the optic disc relative to the fovea, according to the Bixenman and von Noorden's criteria. Ocular sighting dominance was assessed by the hole-in-the-card test and the pointing test. The Mann-Whitney U test and Fisher's exact test were used to determine the association between the ocular sighting dominance and the ocular torsion. RESULTS: The median DFA was significantly larger in the eyes of patients with UCSOP (9.1° in the paretic eyes and 9.3° in the non-paretic eyes) than the eyes of the control group (4.3°, p < 0.001 for both). Ocular dominance tests displayed that, among 22 patients, 11 were paretic eye dominant and the other 11 were non-paretic eye dominant. The sighting-dominant eyes demonstrated significantly smaller median DFA than the non-dominant eyes (8.3° and 10.7°, respectively, p = 0.033), regardless of which eyes were paretic. Ten eyes of ten patients had extorsion, none had intorsion, and all the eyes of remaining 12 patients had no abnormal torsion, qualitatively. All the eyes showing extorsion in fundus photography were non-dominant eyes, regardless of whether the eyes were paretic or non-paretic. CONCLUSIONS: Our findings illuminate the importance of considering ocular sighting dominance for properly assessing ocular torsion in patients with UCSOP. Ocular sighting dominance may have an influence on objective ocular torsion in a way that decreases the torsion in the dominant eye, thereby hindering the abnormal ocular torsion from appearing in that eye.

Effect of modified graded recession and anteriorization on unilateral superior oblique palsy: a retrospective study.

BACKGROUND: Several inferior oblique (IO) weakening methods exist for correction of superior oblique palsy (SOP). A previously reported method involved recession and anteriorization according to IO overaction (IOOA) grade, which might be subjective and cause upgaze limitation and opposite vertical strabismus. Therefore, this study attempted to examine the efficacy of modified graded recession and anteriorization of the IO muscle in correction of unilateral SOP without resulting in upgaze limitation or opposite vertical strabismus. METHODS: A total of 26 patients (male, 16; female, 10; age: 3-40 years) with SOP and head tilt or diplopia underwent modified graded recession and anteriorization. Patients were grouped by the position at which the IO muscle was attached inferior/temporal to the lateral border of the inferior rectus (IR) as follows: (1) 7.0/2.0 mm (4 patients), (2) 6.0/2.0 mm (3 patients), (3) 5.0/2.0 mm (3 patients), (4) 4.0/2.0 mm (11 patients), (5) 3.0/0.0 mm (2 patients), and (6) 2.0/0.0 mm (3 patients). Recession and anteriorization were matched to vertical deviation in the primary position at far distance. Remaining diplopia, head tilt, vertical deviation (≤3 prism diopter (PD), excellent; 4-7 PD, good; and ≥ 8 PD, poor), upgaze limitation, and opposite vertical strabismus were evaluated. RESULTS: The average pre and postoperative 1-year vertical deviation angles in the primary position at far distance were 15.0 ± 5.6 PD and 1.2 ± 2.0 PD, respectively. At 1 year post-surgery, the vertical deviation angles were reduced by 6.8-21.0 PD from those at baseline. Few patients exhibited remaining head tilt, diplopia, upgaze limitation, or opposite vertical strabismus. Correction of hypertropia was excellent in 22 and good in 4 patients. CONCLUSIONS: Modified graded recession and anteriorization of the IO muscle is an effective surgical method for treating unilateral SOP. It exhibits good results and reduces the incidence of opposite vertical strabismus.

[Pay attention to the clinical classification and individualized treatment of superior oblique palsy].

Superior oblique palsy (SOP) has many anatomic variations, and the accompanied paralysis generalization could stimulate the secondary changes of other extra-ocular muscles. Therefore, the clinical manifestations of SOP can be various, and the surgical design is complicated and changeable. It is necessary to understand the clinical development, stages and types of SOP correctly, and to take into account the developmental characteristics of the superior oblique muscle and select the individualized treatment plan. In this article, the SOP manifestations, imaging features, clinical examination and personalized treatment options are discussed, in order to provide some reasonable treatment options for SOP surgery. (Chin J Ophthalmol, 2017, 53: 881-884).

Magnetic resonance imaging of bilateral split lateral rectus transposition to the medial globe.

PURPOSE: Medial transposition of the split or intact lateral rectus (LR) muscle in oculomotor palsy improves extreme exotropia. We studied rectus pulley positions using high-resolution surface coil MRI before and after LR split with medial transposition surgery in a patient with bilateral oculomotor and trochlear nerve palsies. METHODS: This is a report of a 14-year-old girl with 90Δ exotropia due to bilateral oculomotor and trochlear nerve palsies following traumatic midbrain infarction at age 6 years. Surgery comprised longitudinal division of each LR into a superior and inferior, threading of both halves between the inferior rectus (IR) and inferior oblique inferiorly, and inferior to the superior oblique and the superior rectus superiorly, with suturing of each 10 mm posterior to the medial rectus (MR) insertion. RESULTS: Pre-operative MRI of the orbit and extraocular muscles (EOMs) with thin, 2-mm slices revealed bilateral atrophy of all EOMs supplied by the oculomotor and trochlear nerves. Post-operative MRI at 2 months demonstrated no significant changes in rectus EOM pulley positions compared with pre-operative values. CONCLUSIONS: The LR pulley does not change position even after split LR transposition to the MR insertion, confirming the profound constraint of the connective tissue pulley system on the LR path.

Results of anterior tucking of the superior oblique muscle tendon in bilateral fourth nerve palsy.

BACKGROUND: Bilateral fourth nerve palsy is characterised by excyclotorsion, which can be corrected by reinforcement of the anterior tendon fibres of the superior oblique muscle. PATIENTS AND METHODS: A retrospective study of 40 consecutive patients with bilateral acquired fourth nerve palsy operated by a selective tuck of the anterior portion of the superior oblique tendon between 1994 and 2012 was undertaken. Horizontal, vertical and torsional deviations were measured in 9 diagnostic positions of gaze and the field of binocular single vision was evaluated with the Harms tangent screen. Postoperative follow-ups took place at 1 week, 6 months, and ≥3 years. RESULTS: Preoperative mean excyclotorsion was 9° in the primary position and 15° in downgaze. These values decreased to 2° and 5° 6 months after surgery, and 2.5° and 6° at ≥3 years. Immediate post-operative incyclotorsion in upgaze (28 patients) and Brown syndrome (15 patients) regressed spontaneously. The median score of field of binocular single vision improved from 4% preoperatively to 76% postoperatively. CONCLUSIONS: The selective tuck of the anterior tendon fibers of the superior oblique tendon enables an efficient and long-lasting correction of the ocular torsion induced by bilateral trochlear palsy.

Microvascular decompression for superior oblique myokymia: case report.

BACKGROUND: Superior oblique myokymia (SOM) is a rare disorder in which the patient suffers episodic uniocular torsional eye movement associated with diplopia and oscillopsia . Although the pathophysiology has been narrowed down to erratic discharge of the trochlear nerve, yet the exact etiology remains unclear; a handful of cases have been described in association with an identifiable space occupying lesions or dural AV fistulae. Neurovascular compression theory has been postulated in the early 1980s and to our knowledge, very few reports exist in the literature accrediting this hypothesis in the pathogenesis of superior oblique myokymia. CASE REPORT: We report a case of successful resolution of severe medication refractory SOM following microvascular decompression of the trochlear nerve. The clinical response has been sustained for a follow-up period of 18 months to date. CONCLUSION: Microvascular decompression may be considered as a definitive and least destructive surgical option for the treatment of medication refractory superior oblique myokymia.

Postoperative outcomes for unilateral congenital trochlear nerve palsy: A retrospective cohort study.

PURPOSE: Congenital trochlear nerve palsy is the most common cause of vertical strabismus. The goal of this study was to investigate surgical outcomes after superior oblique tendon plication with or without inferior oblique recession in children and adults with unilateral congenital trochlear nerve palsy. METHODS: Data and outcomes were collected in patients with a diagnosis of unilateral congenital superior oblique palsy during a retrospective single-center study conducted at the University Hospital of Tours. A reproducible, standard ophthalmological and oculomotor examination was performed pre- and postoperatively at 1 year, including presence or absence of diplopia, vertical and horizontal deviations, and compensatory head posture. Surgical success, defined as an endpoint including absence of diplopia in primary position, absence of head tilt, and vertical deviation at distance fixation<5 prism diopters (PD), was analyzed. RESULTS: A total of fifty-seven patients (median [IQR] age of 11 years [5-42]) were analyzed. Patients experienced a significant reduction in vertical distance and near deviations (p<0.001), compensatory head tilt (p < 0.001), and diplopia after surgery (p < 0.001). Surgical success was higher in adults (17/24, 70.8%) than in children (15/33, 45.5%), although this did not reach statistical significance (p=0.0657). CONCLUSION: This study suggests that plication of the superior oblique muscle tendon, with or without recession of the inferior oblique muscle, can be effective in treating unilateral congenital trochlear nerve palsy. Further studies are necessary to compare surgical procedures and investigate their efficacy in adults compared to children in the short and long term.

Small tuck for superior oblique palsy.

PURPOSE: To investigate the surgical outcomes of small superior oblique (SO) tuck-denoting minimal tendon laxity-in patients with unilateral SO palsy. METHODS: The medical records of consecutive patients treated with ≤6 mm SO tuck from 2000 to 2018 at Kellogg Eye Center, University of Michigan, were reviewed retrospectively. Tendon tucks were performed to a fairly uniform tension in an amount that just eliminated slack in the tendon. Pre- and postoperative motility measurements were compared. Patients were excluded if they had a history of prior strabismus surgery or concurrent vertical rectus or inferior oblique surgery. RESULTS: A total of 27 cases (14 males) met inclusion criteria. The median age at surgery was 47 years (range 3-74 years). The mean SO tuck (total, both arms of tuck) was 4.9 mm (range, 2-6 mm). After surgery, median hypertropia decreased from 9Δ to 1Δ in primary position and from 20Δ to 4Δ in the SO field of action (contralateral downgaze). Lateral incomitance (difference in hypertropia between contralateral and ipsilateral gaze) decreased from 10Δ to 2Δ (P < 0.001 in each case). Six patients had diplopia in upgaze postoperatively that was not symptomatic enough to require reoperation. Six patients had residual hypertropia requiring additional surgery. CONCLUSIONS: Small SO tuck provided disproportionate correction of hypertropia in the SO field of action and nearly eliminated lateral incomitance without producing unacceptable iatrogenic Brown syndrome. Even in the absence of tendon laxity, SO tuck was a good surgical option for SO palsy in our cohort where there was marked lateral incomitance and the greatest deviation was in the SO field of action.

Inferior oblique myectomy for postoperative limitation of elevation in abduction.

Antielevation syndrome is commonly described following anteriorization of the inferior oblique muscle. A similar phenomenon may occur following inferior oblique muscle recession, creating a distinct strabismus pattern in the setting of cranial trochlear nerve palsy. We report 3 adult patients, 69-72 years of age, who presented at the Stanford Byers Eye Institute with a similar strabismus pattern-limited elevation in abduction following previous inferior oblique muscle recession for congenital/long-standing trochlear nerve palsy. All 3 patients had a small hypertropia in primary gaze with ipsilateral inferior oblique overaction, limited elevation in abduction, and inferotemporal conjunctival scars. Two patients had a V-pattern strabismus. Following myectomy of the previously recessed inferior oblique muscle, elevation in abduction improved, and symptoms resolved in all 3 patients.