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.

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.

Range of forced cyclorotation in superior oblique palsy and V-pattern strabismus.

PURPOSE: To quantify a passive range of cyclorotation using a smartphone application and evaluate its associations with fundus torsion and rectus muscle cyclorotation in superior oblique palsy (SOP) and V-pattern strabismus. METHODS: Fifty-two patients showing overelevation in adduction (30 with congenital SOP and 22 with V-pattern strabismus) underwent forced cyclorotation on the photographs. A photograph of the globe was taken in maximally excyclorotated and incyclorotated positions after marking at the 6 and 12 o'clock limbus under general anaesthesia, and the rotational alignment of these markings was read using the toriCAM application. The degrees of forced cyclorotation were compared between the two groups. Disc-fovea angle on fundus photographs and rectus muscle cyclorotation in the coronal view on orbital computed tomography were correlated with the range of forced excyclorotation. RESULTS: The range of forced excyclorotation was greater in V-pattern strabismus than that in SOP (58.5° vs. 46.8°, p < 0.001), whereas the ranges of incyclorotation were similar between the two groups (39.0° vs. 39.0°, p = 0.543). Regression analysis revealed a significant increase in the range of excyclorotation with the degree of rectus muscle excyclorotation, after accounting for age and angle of hypertropia (r2 = 0.475, p = 0.001). The range of excyclorotation did not correlate with the amount of fundus extorsion and grade of overelevation in adduction. CONCLUSIONS: The range of excyclorotation was correlated with the rectus muscle excyclorotation in these populations, suggesting that the results from this forced cyclorotation test may reflect orbital alignment and oblique muscle status.

The etiologies of isolated fourth cranial nerve palsy: a 10-year review of 158 cases.

PURPOSE: To identify the etiologies of isolated fourth cranial nerve palsy in Ramathibodi hospital, Thailand. METHODS: Patients diagnosed with isolated fourth nerve palsy from January 1, 2009, through July 31, 2020 in Ramathibodi Hospital, were included in this retrospective, observational case series. The demographic data of patients, age at presentation, the etiologies of isolated fourth nerve palsy and neuroimaging results (if indicated) were recorded. RESULTS: We identified 154 unilateral and 4 bilateral cases of isolated fourth nerve palsy. Mean age at presentation was 38.89 ± 25.71 years old. Most of the unilateral cases were congenital (57.79%), with microvasculopathy (27.92%), intracranial neoplasm (8.44%) and other etiologies. Trauma with closed head injury was the most common etiology of bilateral cases (75%), followed by ruptured arteriovenous malformation (25%). Twenty-one of the 43 (48.84%) patients with microvasculopathy fourth nerve palsy underwent neuroimaging, with normal findings, and all patients' symptoms resolved within 6 months of symptom onset. CONCLUSIONS: In our series, most of the isolated fourth nerve palsy cases were congenital, followed in frequency by microvasculopathy and intracranial tumor, as in many studies. In cases of microvasculopathy, the clinical signs and symptoms resolved within 6 months in all cases: observation was sufficient, with no necessity for neuroimaging. However, neuroimaging should be considered in cases with atypical presentations, such as headache, periorbital pain, or if there is rapid progression or no recovery.

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

BACKGROUND: To 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. METHODS: Retrospective 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. RESULTS: The 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%). CONCLUSIONS: The 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.

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.

Clinical characteristics according to the laterality of ocular torsion in unilateral superior oblique palsy.

BACKGROUND: To compare clinical characteristics according to the laterality of objective ocular torsion in patients with unilateral superior oblique palsy (SOP). METHODS: This retrospective study included all patients with a diagnosis of unilateral SOP. They were classified into subgroups according to correspondence between the paretic eye and the extorted eye using fundus photography. Ocular alignment and muscle action were tested by the prism and alternate cover tests and 4-scale movement measure. Various clinical factors, including the amount of preoperative ocular torsion and change in ocular torsion postoperative, were compared between the accordance and disaccordance groups. RESULTS: A total of 70 Asian patients (140 eyes) were included and underwent fundus photography preoperatively. Excyclotorsion in the paretic eye was defined as accordance (45 patients), excyclotorsion in the nonparetic eye was defined as disaccordance (25 patients). The presence of horizontal strabismus was detected in 28 (62%) patients in the accordance group and only 8 (32%) patients in the disaccordance group (p = 0.024). All horizontal strabismus observed in the accordance group involved exodeviation. The proportion of horizontal strabismus surgery was also significantly larger in the accordance group than the disaccordance group (p = 0.039). Among those patients, there were 26 who underwent fundus photography postoperatively. There was significant reduction in ocular excyclotorsion postoperatively in the accordance group (p = 0.001), but no significant reduction postoperatively in the disaccordance group (p = 0.270). There was no significant correlation between the amount of torsional reduction and the amount of vertical deviation reduction (p = 0.979). CONCLUSIONS: In cases of preoperative excyclotorsion in paretic eyes, careful consideration of combined horizontal misalignment which may require surgical correction is helpful to manage unilateral SOP.

Expression of MyoD, insulin like growth factor binding protein, thioredoxin and p27 in secondarily overacting inferior oblique muscles with superior oblique palsy.

BACKGOUND: To identify and compare specific protein levels between overacting inferior oblique (IO) muscles in superior oblique (SO) palsy patients and normal IO muscles. METHODS: We obtained 20 IO muscle samples from SO palsy patients with IO overaction ≥ + 3 who underwent IO myectomies (IOOA group), and 20 IO samples from brain death donors whose IO had functioned normally, according to their ophthalmological chart review (control group). We used MyoD for identifying satellite cell activation, insulin-like growth factor binding protein 5 (IGFBP5) for IGF effects, thioredoxin for oxidative stress, and p27 for satellite cell activation or oxidative stress in both groups. Using immunohistochemistry and Western blot, we compared expression levels of the four proteins (MyoD, IGFBP5, thioredoxin, and p27). RESULTS: Levels of thioredoxin and p27 were decreased significantly in the IOOA group. MyoD and IGFBP5 levels showed no significant difference between the groups. CONCLUSIONS: Based on these findings, the overacting IOs of patients with SO palsy had been under oxidative stress status versus normal IOs. Pathologically overacting extraocular muscles may have an increased risk of oxidative stress compared with normal extraocular muscles.

Are we overlooking masked bilateral congenital superior oblique palsy in children: is it possible to diagnose before surgery?

PURPOSE: To describe the characteristics of children who had subsequent contralateral superior oblique underaction (SOUA) and inferior oblique overaction (IOOA) after unilateral inferior oblique weakening surgery and to identify suggestive clinical features for masked bilateral fourth nerve palsy. METHODS: The medical records of children who underwent unilateral inferior oblique tenotomy as a single procedure for unilateral superior oblique palsy were all reviewed. Diagnosis was based on evaluation of ocular misalignment in nine diagnostic gaze positions and presence of SOUA, IOOA, and abnormal head position. RESULTS: The study was conducted with 29 children. All children had preoperative unilateral IOOA and SOUA. Eleven children (37.9%) had hyperesodeviation in the affected eye, while others (62.1%) had hyperexodeviation. The mean age at surgery was 6.66 ± 1.87 (4-10) years. The mean vertical deviation, exodeviation, and the amount of IOOA were decreased postoperatively (p < 0.001 for all). Among the 29 children, 22 had no residual ipsilateral IOOA, 2 had ipsilateral IOOA, and 5 had ipsilateral inferior oblique underaction (IOUA) at last visit. Three children had contralateral SOUA, IOOA, and hyperdeviation at follow-up visits, one of whom had IOUA on the operated eye. There was no difference of preoperative features between children with or without subsequent contralateral superior oblique palsy. CONCLUSION: Bilateral congenital superior oblique palsy may be overlooked in children in spite of detailed preoperative evaluation. Masked bilaterality should always be kept in mind in cases with unilateral pathology. Patients should be informed about the possibility of bilaterality.

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.

Combined Brown syndrome and superior oblique palsy without a trochlear nerve: case report.

BACKGROUND: Congenital Brown syndrome is characterized by limited elevation particularly during adduction. The pathogenesis of congenital Brown syndrome is still controversial. CASE PRESENTATION: A 6-year-old boy had been tilting his head to the left since infancy. He showed right hypertropia (RHT) of 2 prism diopters (Δ) in the primary position. He showed RHT 6Δ in right gaze, RHT 2Δ in left gaze, RHT 12Δ in right head tilt, and orthotropia in left head tilt. The right eye showed limitation of elevation and depression on adduction, and the left eye showed overdepression on adduction. MR images showed an absent right trochlear nerve with a hypoplastic ipsilateral superior oblique muscle. CONCLUSIONS: Congenital Brown syndrome may be associated with an absent trochlear nerve and hypoplastic superior oblique muscle suggesting an etiologic mechanism of congenital cranial dysinnervation disorder.

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.

Congenital superior oblique palsy in a patient with VACTERL association.

Different types of ophthalmological defects have been reported to be accompanying vertebral anomalies, anal atresia, cardiac malformations, tracheoesophageal fistula, renal anomalies, and limb anomalies (VACTERL) association. A 7-year-old girl with a history of VACTERL association presented with upward drifting of the left eye and anomalous head posture to the right side and was diagnosed with congenital fourth nerve palsy. We report the first case representing a combination of congenital fourth nerve palsy with VACTERL association.

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

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.

Superior oblique palsy as the initial manifestation of anti-contactin-1 IgG4 autoimmune nodopathy: A case report.

Autoimmune nodopathy (AN) is a group of peripheral neuropathies caused by antibodies targeting the nodes of Ranvier or paranodes. It typically presents with sensory ataxia, distal limb weakness, and tremor, and often has a subacute onset, with limited response to immunoglobulin or corticosteroids. We report a case of anti-contactin-1 neuropathy initially manifesting as isolated superior oblique palsy, aiming to broaden the clinical spectrum of the disease. A 68-year-old male with well-controlled diabetes, hypertension, and hyperlipidemia developed acute binocular vertical diplopia, progressing over two months to include distal paresthesia, sensory ataxia, ageusia, and dysarthria. Concurrent nephrotic syndrome was identified. Nerve conduction studies supported demyelination. Despite treatment with intravenous methylprednisolone followed by long-term immunosuppression, some disability persisted. Serum archived during his admission tested positive for anti-contactin-1 IgG, with IgG4 as the predominant subclass, in the flow cytometry assay for AN. This case extends the clinical spectrum of AN. Some cases of isolated cranial nerve palsies, especially in the relevant context like nephrotic syndrome, may be attributed to AN. Prompt initiation of more effective therapies, such as rituximab, could significantly improve outcomes.

The Frequency and Manifestations of Ocular Causes of Abnormal Head Posture.

PURPOSE: To determine the frequency and manifestations of different ocular causes of abnormal head posture (AHP). METHOD: This prospective, consecutive case series study was performed on 149 patients with ocular AHP at Farabi hospital, Iran, from February 2020 to June 2021. All patients underwent routine ophthalmic examinations. The manifestation of AHP was determined by direct observation from three viewing angles, while the patient read the smallest line on the vision chart that they could see. In front, above, and lateral gazes, observations were performed to find head tilt, head turn, and chin abnormal position, respectively. A picture with habitual AHP was taken from all patients. The amount of head tilt was measured by calculating the angle between the line that connects the lips center to the center of the eyebrows and the vertical line using the Corel Draw X7 computer software. RESULTS: The mean age of 149 patients with ocular AHP [101 (67.8%) males and 48 (32.2%) females] was 16.2 ± 12.2 (range, 2-57) years. The most common ocular sources of AHP were found to be superior oblique palsy (SOP) in 66 (44.3%) patients, 54 (36.2%) cases with Duane's retraction syndrome (DRS), and 12 (8.1%) patients with nystagmus. Other frequent causes of ocular AHP were dissociated vertical deviation (DVD) in 5 (3.4%), A and V pattern strabismus in 3 (2.0%), and 2 cases (1.3%) in each of Brown syndrome, inferior rectus (IR) palsy, and congenital fibrosis of the extraocular muscles (CFEOM). The most common manifestations of AHP in all cases were "pure head turn" (48.3%), followed by "pure head tilt" (24.8%), "simultaneous head tilt and head turn" (20.8%), and "chin up" (6.0%). The mean head tilt among all patients with head tilt was 10.4° ± 8.9° (range, 5.0°-31.7°). CONCLUSION: The most frequent ocular sources of AHP were SOP, DRS, and nystagmus, followed by DVD, A and V pattern strabismus, IR palsy, CFEOM, and Brown syndrome. In addition, pure head turn and pure head tilt were the most common manifestations of ocular AHP but were not always seen in the same direction or combination as previously reported with these etiologies.

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.

Isolated Sudden-Onset Trochlear Nerve Palsy Associated with Mild Novel Coronavirus Disease (COVID-19) Infection.

PURPOSE: To present a case of sudden isolated unilateral trochlear nerve palsy of new onset associated with a COVID-19 infection without a severe course. METHODS: A 49-year-old previously healthy man suddenly noticed seeing double while going down the stairs to go out for the first time the day after the completion of medical treatment and home isolation for COVID-19. There was no systemic disease or history of trauma. RESULTS: Magnetic resonance imaging of the brain and orbits was normal and the neurology examination revealed no pathology. The acute onset of the diplopia, the small vertical fusion amplitude, and the lack of facial asymmetry supported acquired trochlear nerve palsy. CONCLUSIONS: Trochlear nerve palsy has rarely been reported in association with the various types of viral infections. To the best of our knowledge, this is the first case of isolated unilateral trochlear nerve palsy with no additional neurological finding or any radiological finding that is possibly associated with mild SARS-CoV-2 infection.

Modified inferior oblique anterior transposition for dissociated vertical deviation combined with superior oblique palsy: A case report.

BACKGROUND: Inferior oblique anterior transposition (IOAT) has emerged as an effective surgery in the management of dissociated vertical deviation (DVD) combined with superior oblique palsy (SOP). Traditional IOAT usually provides satisfactory primary position alignment and simultaneously restricts the superior floating phenomenon. However, it also increases the risk of the anti-elevation syndrome and narrowing of the palpebral fissure in straight-ahead gaze, especially after the unilateral operation. CASE SUMMARY: We report the outcomes of the modified unilateral IOAT in two patients with unilateral DVD combined with SOP. The anterior-nasal fibers of the inferior oblique muscle were attached at 9 mm posterior to the corneal limbus along the temporal board of the inferior rectus muscle, the other fibers were attached a further 5 mm temporal to the anterior-nasal fibers. Postoperatively, both hypertropia and floating were improved, and no obvious complications occurred. CONCLUSION: In these cases, the modified unilateral IOAT was an effective and safe surgical method for treating DVD with SOP.

Improvement in health-related quality of life with Botulinum toxin A injection in acquired superior oblique palsy.

Purpose: This study aimed to investigate the outcomes of Botulinum toxin A (BTA) injection into the inferior oblique (IO) muscle for the management of unilateral acute acquired superior oblique palsy (SOP) and to evaluate changes in health-related quality of life post-injection using the Adult Strabismus-20 (AS-20) questionnaire. Methods: A prospective cohort study was performed in patients with unilateral acute acquired SOP who received BTA injections. Four units of BTA were injected into the ipsilateral IO muscle. Ocular examinations were performed pre-and post-injection, including alignment, ocular movement, and cyclotorsion deviation. The patients' AS-20 questionnaire scores were analyzed. Results: A total of 21 patients with acute acquired SOP were included. The initial median vertical deviation was 5 PD (range 1-16), which was improved to 0 PD (range 0-10) at both 1 and 6 months post-injection (p < 0.001 and p < 0.001, respectively). The median torsional deviation was 7° (range 2-18) at baseline and resolved to 0 degrees (range -3-5) at the 1-month and 0° (range -2-7) at the 6-month follow-up (p < 0.001 and p < 0.001, respectively). There were significant increases in the overall score (OAS), psychosocial subscale score (PSS), and functional subscale score (FSS) from baseline values at both the 1-month (p < 0.001, p < 0.001, and p = 0.001, respectively) and 6-month follow-up (all p < 0.001). Conclusion: Injecting BTA into the ipsilateral IO muscle successfully resolved vertical and torsional deviations and significantly improved quality-of-life scores. Our findings show that BTA treatment, as an early treatment for acute acquired SOP, can help patients by significantly improving their quality of life.