Vertical Strabismus Research Articles

Investigating the Overaction of the Inferior Oblique Muscle and Associated Vertical Strabismus: Indications, Timing, and Methods of Surgical Intervention

Treatment of the vertical strabismus due to the overaction of the inferior oblique extraocular muscle usually requires surgical intervention. In addition to the cosmetic issues, the main indications for surgical treatment of the inferior oblique overaction are the presence of cyclotropia and torsional diplopia. Most procedures target the weakening of the inferior oblique muscle; however, there is the risk of some intraoperative and postoperative complications, including highly invasive procedures, difficulty of technical implementation because of the need for manipulations in inaccessible locations of the globe near the optic nerve, macular area, and large vessels, long duration of the surgery, inability to determine the dosage of the outcomes of the surgery, and poor functional outcomes. Most complications are absent in the procedure of anterior transposition in which the neuro-fibrovascular bundle serves as the axis of rotation of the inferior oblique muscle. This technique changes the inferior oblique muscle’s action field and increases treatment effectiveness. Despite the advantages of this technique, its application is still limited because of the lack of methods for controlling the amount of anterior transposition to treat inferior oblique overaction, particularly of small degrees.

Evaluation of a Novel Virtual Reality Simulated Alternate Cover Test to Assess Strabismus: A Prospective, Masked Study

A sensorimotor examination is the gold standard for strabismus diagnosis and quantification but requires a highly skilled examiner and may be limited by a child's cooperation. Virtual reality (VR) employs eye-tracking technology to monitor eye position and may be able to measure strabismus. The aim of this study was to assess a prototype VR-simulated alternate cover test to detect and measure strabismus. Prospective, masked diagnostic test study. Patients aged 5-18 years with visual acuity of 20/80 or better were prospectively enrolled to undergo strabismus measurements using a VR simulated alternate cover test (Olleyes, Inc., Summit, NJ) followed by an alternate cover test performed by a masked pediatric ophthalmologist or orthoptist. The main outcome measure was correlation between gold standard and VR-obtained strabismus measurements (in prism diopters [PD]) in primary gaze at near using Pearson correlation coefficients and Bland-Altman analysis with limits of agreement (LOA). A secondary measure was the diagnostic accuracy for the VR headset to detect strabismus. A total of 85 participants were enrolled, mean ± standard deviation age was 10.8 ± 3.8 years, 45.9% (39/85) male. 40.0% (34/85) had strabismus: 17.7% (15/85) esotropia, 22.4% (19/85) exotropia, and 5.9% (5/85) vertical strabismus. 52.9% (18/34) of strabismus was intermittent. The overall correlation between VR and gold standard strabismus measurements was moderate but significant (r = 0.42, 95% CI 0.22, 0.58, P < .001), and correlation was strong for esotropia and constant deviations (r = 0.74, 95% CI 0.38, 0.91, P = .001 and r = 0.74, 95% CI 0.39, 0.91, P < .001, respectively). In participants with horizontal strabismus, Bland-Altman analysis showed a mean difference between standard and VR measurements of 3.55 ± 8.33 PD for esotropia (upper and lower LOA 19.89, -12.78 PD) and 17.15 ± 11.20 PD for exotropia (LOA 39.09 and -4.79 PD). Sensitivity for detecting strabismus was low: 27.6% (95% CI 12.7, 47.2), but specificity was high: 87.5% (95% CI 75.9, 94.8). A prototype VR simulated alternate cover test showed a moderate but significant correlation with the gold standard sensorimotor examination and correlation was strong in those with esotropia and constant deviations. While the level of agreement demonstrated by this novel VR technology is promising, further improvements are needed before clinical deployment. However, this study demonstrates that VR has the potential to expand our ability to detect, measure, and monitor strabismus.

Validity and Reliability of 2 Cirrus Optical Coherence Tomography Procedures for Measuring Objective Ocular Torsion

Torsional eye position by the disc-fovea angle (DFA) is a relevant objective parameter in vertical strabismus. DFA measurement with optical coherence tomography (OCT) has proven to be a good alternative to the gold standard measurement in fundus photography. Our study aims to analyze the validity and reliability of 2 undescribed Cirrus high-definition OCT (HD-OCT; Carl Zeiss Meditec) methods that offer clinical advantages for measuring objective cycloposition in normal patients compared with Spectralis spectral-domain OCT (Heidelberg Engineering) and the reference method. Prospective validity and reliability analysis. Objective cycloposition by means of the DFA was measured in the right eyes of 59 binocularly normal individuals attending the ophthalmology service of a medical institution. DFA was obtained by fundus photography (gold standard), FoDi software of Spectralis spectral-domain OCT, HD 1 line scan of Cirrus HD-OCT, and macular cube of Cirrus HD-OCT (fundus, FoDi, line, and cube methods, respectively). Measurements were performed 3 times for each method and the patient was repositioned and realigned between captures. Posterior manual quantification was made by 2 observers with external protractor software for the fundus and cube methods. The 3 OCT methods showed and excellent agreement with fundus photography (ICC 0.83-0.84) with no significant differences comparing mean values (P = .36 for fundus-FoDi, P = .09 for fundus-line, and P = .09 for fundus-cube). Absolute differences between methods were 1.5°. All methods showed excellent reliability (ICC 0.92 for FoDi, 0.91 for line, 0.92 for cube, and 0.91 for fundus). The minimal detectable change was lower than 3° and the absolute difference between repeated measurements was 1° for all methods. Interrater reliability was excellent for methods requiring manual quantification (ICC 0.98 for cube, ICC 0.94 for fundus). Measurement of the DFA by Cirrus HD-OCT methods in normal patients was a valid and reliable alternative for the cycloposition assessment. Among the methods, the Cirrus OCT HD 1 line improved clinical performance due to the simplicity and speed of measurement, with no need to export the image for quantification.

The Outcome of Inferior Oblique Myectomy for Apparent Inferior Oblique Overaction Associated with Craniosynostosis.

Strabismus in patients with craniosynostosis is common, but surgical correction of strabismus in these patients remains challenging. We report our findings in six patients (four of whom were Korean) with craniosynostosis who underwent strabismus surgery to specifically address V-pattern horizontal strabismus with moderate-to-severe inferior oblique (IO) overaction, using IO myectomy at a single tertiary hospital between 2005 and 2016. We recorded preoperative characteristics including sex, age, type of strabismus, versions grading, refractive error, and visual acuity. The grading of cyclorotation of horizontal rectus muscles by V-pattern categorized using coronal computed tomography imaging. Of the six patients, exodeviation was found in four patients and vertical deviation in two patients in primary position. One patient had both horizontal and vertical strabismus. Available computed tomography imaging showed that V-patterns were category 1 (mild) in two patients, category 2 (moderate) in one patient, and category 3 (severe) in two patients. Complete success was defined as absence of IO overaction any more. Overall complete success rate of IO myectomy was 83.3%. IO myectomy appeared to have some benefits in V-pattern horizontal strabismus with moderate-to-severe IO overaction in patients with craniosynostosis.

Characteristics and Trends of Strabismus Surgeries at a Tertiary Hospital Over 2 Decades - What Can Be Learned for Years to Come?

ABSTRACT Purpose To analyze characteristics and trends of strabismus surgeries in an Israeli hospital over 2 decades. Methods A descriptive, retrospective study including all strabismus surgeries (666) performed during 2000–2019 at an Israeli tertiary hospital. Electronic medical records (EMRs) were directly retrieved to produce an anonymized database. Results No trends were evident for age, sex, or ethnicity (p = .294, 0.914 and p = .167, respectively). The mean number of horizontal muscles remained stable, while an increase was noted in the mean number of muscles operated on to repair vertical strabismus (p < .0001). Among acquired cases, a 2.67-fold increase was noted in the proportion of spontaneous strabismus and a decrease of traumatic causes to a third (p < .001). An increase was noted in the proportion of exotropia among horizontal strabismus corrections (p = .022), and esotropia correction techniques distribution changed (p = .004). Reoperations comprised a third of all cases during both decades (p = .198). Reoperations were more prevalent among younger and Jewish patients (p < .001 and p = .024, respectively). Techniques to correct esotropia and exotropia differed significantly between primary surgeries and reoperations (p < .00001 each). Conclusions The complexity of surgical techniques increased over time. Ethnic minorities were less prone to reoperations.

Effect of vertical central plication on vertical deviations

PurposeTo evaluate the surgical effect of the Wright central plication on vertical rectus muscles to correct vertical strabismus. MethodsIn this multicenter, retrospective, observational outcomes study, data were collected from two surgeons in different practice settings (2017-22). All patients who underwent vertical rectus central plication were included; those undergoing any concurrent strabismus surgery for vertical strabismus were excluded. Primary outcome was amount of strabismus correction in prism diopters per vertical rectus central plication. Secondary outcome was to determine factors associated with better or worse surgical outcomes and patient and patient responses. Data were analyzed using descriptive and bivariate statistics. ResultsA total of 36 patients were included. Mean age was 60 years. Mean follow-up was 8.4 months. Of the 36 patients, 11 (31%) had idiopathic strabismus, and 7 (19%) had congenital superior oblique palsy. The remainder had a history that included prior ocular surgery, trauma, and Brown syndrome; 16 (44 %) had prior strabismus surgery. Of 31patients with preoperative diplopia, 23 (74%) had postoperative resolution of diplopia, and 10 of 16 patients with preoperative prisms (63%) no longer required prisms postoperatively. Mean vertical deviation change was 4.7Δ. Subgroup analysis removing patients with congenital superior oblique palsy showed a larger response of 5.5Δ. 78% of patients had a final deviation <5Δ. No complications or induced postoperative diplopia was reported. ConclusionsIn our study cohort, vertical rectus central plication corrected approximately 5Δ (range, 4.5Δ-5.5Δ) of vertical strabismus due to a variety of causes.

Changes in ocular extorsion after horizontal muscle surgery in patients with intermittent exotropia coexisting with hypertropia and mild inferior oblique overaction.

To investigate changes in vertical strabismus and extorsion in patients with intermittent exotropia and mild unilateral inferior oblique muscle overaction (IOOA) who underwent horizontal muscle surgery without vertical or oblique muscle surgery. The medical records of 41 patients were retrospectively analyzed. The patients were followed up for at least 6 months after surgery. Fundus photography was performed before and after surgery, and the sum of the angles of torsion in both eyes was used to measure changes in extorsion using ImageJ software. The enrolled patients were divided into two groups according to the degree of IOOA: patients with grade 1 IOOA were placed in +1 IOOA group and those with grade 2 IOOA in +2 IOOA group. The pre- and postoperative angles of horizontal and vertical strabismus and extorsion were compared between the two groups. The +1 IOOA and +2 IOOA groups included 24 and 17 patients, respectively. The angle of preoperative exotropia did not differ significantly: 25.54 ± 5.68 prism diopters (PD) and 25.65 ± 8.11 PD in the +1 IOOA and +2 IOOA groups, respectively. In the +1 IOOA and +2 IOOA groups, hypertropia was 2.67 ± 1.52 PD and 2.82 ± 1.13 PD, respectively, and extorsion angles were 7.14 ± 2.77° and 7.94 ± 2.87°, respectively. As the IOOA degree increased, the extent of hypertropia and extorsion also increased. However, there were no significant differences between the two groups. Postoperative angles of hypertropia and extorsion significantly decreased in both groups (p < 0.001) after surgery. The degree of change in hypertropia and extorsion was not significantly different between the two groups (p = 0.563 and p = 0.354, respectively). Hypertropia and extorsion improved significantly after horizontal muscle surgery in patients with mild unilateral IOOA and intermittent exotropia. There was no significant difference in the improvement in hypertropia or extorsion between IOOA grades I and II.

Prevalence, Clinical and Imaging Characteristics of Superior Ophthalmic Vein Periphlebitis in Thyroid Eye Disease.

To determine the prevalence, clinical features, and radiographic findings of superior ophthalmic vein periphlebitis (SOVP) in thyroid eye disease (TED). Patients with a clinical diagnosis of thyroid eye disease and contrast-enhanced imaging were included. Imaging was reviewed for the presence of SOVP, and patients with SOVP were compared to those without. A random eye was determined to be the affected eye in patients without SOVP. A total of 212 patients met the inclusion criteria. Unilateral SOVP was identified in 4.7% of cases. There was no significant difference in age ( p = 0.22), gender ( p = 0.09), or disease duration ( p = 0.14) between patients with and without SOVP. There was a significant ( p < 0.05) difference in stage classification and clinical activity core between the groups. The affected eye in patients with SOVP had significantly ( p < 0.05) greater margin reflex distance 1, degree of relative proptosis, horizontal motility restriction, and vertical motility restriction than in patients without SOVP. There was no significant difference in horizontal strabismus ( p = 1.0), vertical strabismus ( p = 0.87), or relative intraocular pressure ( p = 0.77). On imaging, the maximal diameter of the SR and IR were found to be significantly ( p < 0.05) larger in the affected eye of patients with periphlebitis; however, there was no difference in measured diameter of the medial rectus and ( p = 0.30) or lateral rectus ( p = 0.78). SOVP is an under-reported imaging finding of thyroid eye disease. It is associated with significantly greater margin reflex distance 1, relative proptosis, and motility restriction on exam as well as larger superior rectus and inferior rectus diameter on imaging. These patients tend to present in the active stage of disease with greater clinical activity score.

Significance of accurately interpreting the Bielschowsky tilt test in the differential diagnosis of superior oblique muscle paralysis

Superior oblique muscle paralysis is a common type of vertical rotatory strabismus with various subtypes. Regardless of the subtype, the Bielschowsky tilt test plays a crucial role in the diagnosis of superior oblique muscle paralysis and is often considered a significant criterion for diagnosis and differential diagnosis. However, the sensitivity and specificity of the Bielschowsky tilt test for diagnosing superior oblique muscle paralysis are not 100% due to the mechanism involved. The test is not solely based on extraocular muscle imbalance but also involves reflex pathways of the vestibular system and central nervous system. Consequently, lesions affecting corresponding areas may yield positive results in the Bielschowsky tilt test. Additionally, vestibular and central nervous system lesions can also cause strabismus, leading to a lack of one-to-one correspondence between a positive Bielschowsky tilt test and superior oblique muscle paralysis. Therefore, correctly interpreting the role of the Bielschowsky tilt test in superior oblique muscle paralysis is of paramount importance for the effective clinical management and treatment of associated conditions.

Clinical efficacy of modified Yokoyama procedure with extraocular muscle transposition for high myopic eyes with restrictive esotropia

Objective: To investigate the clinical efficacy of the modified Yokoyama procedure with extraocular muscle transposition for high myopic eyes with restrictive esotropia. Methods: A retrospective case series study was conducted. Clinical data were collected from patients who underwent the modified Yokoyama procedure with extraocular muscle transposition for high myopic eyes with restrictive esotropia at Eye Hospital of Shandong First Medical University from February 2017 to February 2022. During the procedure, the superior rectus and lateral rectus muscles were fully separated. A longitudinal blunt incision was made in the central muscle belly extending posteriorly to 12-14 mm from the muscle insertion. The temporal half of the superior rectus muscle and the upper half of the lateral rectus muscle belly were transposed and secured to the contralateral muscle insertion. Simultaneously, medial rectus muscle recession was performed. Follow-up visits were conducted at 1 week, 1 month, 3 months, and 6 months postoperatively. Patients' ocular alignment, eye movements, improvement in compensatory head posture, objective degrees of strabismus using synoptophore, changes in extraocular muscles and globe position on orbital CT scan were recorded. Surgical complications were also documented. Results: Five patients (8 eyes) were included in this study, including 4 females (7 eyes) and 1 male (1 eye), with an average age of (63±11) years and an average axial length of (34.58±2.25) mm. The medial rectus muscle recession during surgery was (7.6±2.3) mm. Preoperatively, all patients had esotropia with a horizontal range of+15°to+45° and a vertical range of+15°to+45°. Significant limitations in lateral and upward gaze were observed, with a degree of restriction ranging from-3 (-4 to-1). Three patients with bilateral involvement and one patient with unilateral involvement exhibited significant compensatory head postures. One patient with unilateral involvement had no compensatory head posture. Preoperative orbital CT scans indicated nasal displacement of the superior rectus muscle and inferior displacement of the lateral rectus muscle, with the eyeball herniating from the muscle cone. At the 6-month follow-up, all patients achieved nearly orthophoric alignment. Objective degrees of horizontal strabismus ranged from-4°to+7°, and vertical strabismus ranged from 0°to +6°, as determined by synoptophore examination. Eye movements significantly improved, with a degree of restriction of-1 (-2 to-1) for lateral gaze and-2 (-3 to-1) for upward gaze. Compensatory head postures disappeared, and orbital CT scans indicated the eyeball was located within the muscle cone. There were no severe complications such as anterior segment ischemia, muscle adhesions, disease recurrence, secondary glaucoma, or globe penetration. Conclusion: The preliminary clinical outcomes of the modified Yokoyama procedure with extraocular muscle transposition for high myopic eyes with restrictive esotropia are promising.

Variation between surgeons in reoperation rates following vertical strabismus surgery: Associations with patient and surgeon characteristics and adjustable sutures.

To quantify inter-surgeon variation in vertical strabismus surgery reoperation rates, and to explore associations of reoperation rate with practice type and volume, surgical techniques, and patient characteristics. Fee-for-service payments to providers in a national database for Medicare beneficiaries having vertical strabismus surgery between 2012 and 2020 were retrospectively analyzed to identify reoperations in the same calendar year. Predictors of the rate of reoperation for each surgeon were determined by multivariable linear regression. Among 73 surgeons, the reoperation rate for 1-vertical muscle surgery varied from 0.0% to 40.7%. Due to the presence of high-volume surgeons with high reoperation rates, just 11% of surgeons contributed over half of the reoperation events for 1-vertical muscle surgery. Use of adjustable sutures, surgeon gender, and surgical volume were not independently associated with surgeon reoperation rate. Associations of reoperation with patient characteristics, such as age and poverty, were explored. Patient poverty was independently associated with a lower surgeon reoperation rate (p = 0.03). Still, the multivariable model could explain only 14.2% of the variation in surgeon reoperation rate for 1-vertical muscle. Patient-level analyses which ignore inter-surgeon variation will be dominated by the practices of a small number of high-volume, high-reoperation surgeons. There are order-of-magnitude variations in reoperation rates among strabismus surgeons, the cause of which remains largely unexplained.

Strabismus is more than a misalignment; a cross-sectional pilot study of HRQOL in Finnish strabismic adults referred to a university hospital.

To evaluate associations between the health-related quality of life (HRQOL) and demographic, self-reported strabismus-related and orthoptic status variables in Finnish strabismic adults. Participants (n = 137) of this study were adult patients who previously participated in the pilot study to translate and validate Adult Strabismus Questionnaire (AS-20) into Finnish. For this study, the participants' orthoptic status were collected among the previously obtained self-reported demographic and strabismus-related data. The refined AS-20 structure of 18 items and four subscales of self-perception, interaction, reading function and general function was used. Low scores on AS-20 indicate low HRQOL. The associations were evaluated with cross-tabulation and nonparametric methods of Mann-Whitney U and Kruskal-Wallis tests. Statistical significance was set at p < 0.05. Interaction subscale scores were the highest of all subscale scores among the participants. Age had an association with HRQOL in self-perception and the youngest participants had the lowest scores. Importantly, participants who did not experience diplopia suffered from lower self-perception and interaction but reported higher scores on reading function and general function subscales compared to the participants who experienced diplopia. Exotropia with or without vertical strabismus were most common types among the participants. The education background was not associated with HRQOL. Impacts of strabismus are similar in Finnish strabismic adults compared to international studies. Healthcare professionals and decision-makers should always consider the psychosocial impact of strabismus on patients without diplopia when making decisions on strabismus treatment and care processes.

Binocular Function in Adults Before and after Strabismus Surgery

Purpose: To evaluate the state of binocular vision, the amount and direction of the ocular deviation before and after strabismus surgery in adult patients and to monitor the occurrence of postoperative complications. Methods: The retrospective study of 58 adult patients with selected types of strabismus who were surgically treated in the Eye Department of the Tomas Bata Regional Hospital in Zlín. We evaluated the amount and the degree of the primary ocular deviation and the binocular alignment before and after surgery, as well as the state of binocular vision after surgery and the occurrence of postoperative complications. Results: The average deviation in convergent strabismus before surgery was +23.46 degrees, after surgery +6.6 degrees, in divergent strabismus it was -21.5 degrees, after surgery -1.48 degrees, for vertical strabismus before surgery +12.5 degrees and +3.75 degrees after surgery and in paralytic strabismus +20 degrees before surgery and +3 degrees postoperatively. Preoperatively there was effectively no binocular vision in up to 63.9% of patients, superposition occurred in 31%, fusion in 5.1%. No patient had stereopsis before surgery. After surgery, superposition was present in 39.7%, fusion in 31% and stereopsis in 6.9% of patients. Only 22.4% of patients experienced no binocular vision after surgery. Of the selected 21 patients out of 58 with an observation period of at least 3 years, we observed an improvement or development of binocular vision functions after surgery in 12 patients and no improvement of binocular vision functions in 9 patients. In the first group, 58.3% had a stable deviation throughout the follow-up period. While in the second group the deviation was stable in only 33.3%. We can assume that the improvement in binocular vision function after strabismus surgery, leads to a greater longer-term stability of postoperative deviations. Conclusion: Strabismus surgery in adult patients is an effective and safe method, which is not only a cosmetic procedure used to adjust the position of the eyes, but also enables us to induce or improve the state of binocular vision functions.

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

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. 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. 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). 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.

Slab-off prism for symptomatic, vertical heterophoria in the reading position

To describe uncommon techniques that induce compensatory strabismus utilizing slab-off spectacle prism to treat symptomatic incomitant vertical strabismus in adults with diplopia in the reading position only. The medical records of consecutive patients having a chief complaint of diplopia in the reading position that was treated with slab-off prism correction were reviewed retrospectively. Success of the slab-off spectacle prism correction was determined at the follow-up visit or by phone call for any patients who did not return for a follow-up examination. Five adult subjects were identified, ranging in age from 55 to 75 years (mean age, 65.6 years). All 5 patients complained of vertical diplopia during reading. Symptoms resolved with slab-off prism in all 5 cases. Three patients had symptomatic incomitant vertical strabismus occurring only in the reading position. All 3 of these patients remained in slab-off prism at in-office follow-up. Slab-off spectacle prism in non-digitally manufactured multifocal lens prescriptions was an effective nonsurgical treatment option in this descriptive study of 5 patients with diplopia in the reading position only, 3 of whom had symptoms related to small-angle vertical strabismus in the reading position only, without anisometropia.

Radiological findings in patients with isolated acute-onset ocular motility disorders

ObjectivesTo image or not to image is a critical question in patients with isolated acute-onset ocular motility disorders (AOMD), without any neurological symptoms/signs. Imaging may help in diagnosis; but is associated with risks and costs. The study aimed to evaluate radiological findings in patients with apparently isolated AOMD on clinical exam, and identify patient/disease characteristics more likely to be associated with positive imaging. MethodsA retrospective review of patient charts with isolated AOMD (<3 months onset), who were examined by an ophthalmologist and had imaging at a tertiary-care center over a period of 18 months, was conducted. Ophthalmology exam and diagnostic imaging findings were recorded. Radiological findings were classified as “clinically relevant”, “non-relevant”, and “normal/no positive” findings. Results46 patients were included (3–91 years; 27 males, 19 females). 19 were clinically classified as nerve palsy (1 third, 10 fourth, and 8 sixth nerve), 14 acute-onset esotropia, 3 acute-onset exotropia, 7 acute-onset vertical strabismus inconsistent with nerve palsy, and 3 limitation of elevation/suspected dorsal midbrain syndrome. We found 8/46 (17%) with clinically relevant imaging findings; of these, 5/46 (11%) had positive neuro-imaging findings (mass, malformation, aneurysm, infarct) and 3/46 (7%) had positive orbital imaging findings (thyroid eye disease). Positive neuro-imaging was more common in patients with certain symptoms (headache), in certain clinical diagnostic entities (dorsal midbrain syndrome spectrum, acute-onset esotropia), and in younger patients (<40 years). ConclusionsPositive neuro-imaging findings may be seen even in patients with apparently isolated ocular symptoms/signs on clinical exam. This data may help institutions with decision-making and policy formulation for imaging patients with isolated AOMD.

Ophthalmologic Manifestations of Ocular Myasthenia Gravis

Purpose: We investigated the ophthalmic manifestations observed in patients diagnosed with ocular myasthenia gravis.Methods: In total, 58 patients diagnosed with ocular myasthenia gravis visited the ophthalmology and neurology departments between January 2011 and August 2022. Patients were followed for &gt; 6 months; their ophthalmic manifestations were analyzed retrospectively.Results: The study included 29 males and 29 females with a mean age of 55.52 ± 15.60 years. Among the patients, 31 tested positive for anti-acetylcholine receptor antibodies, resulting in a positive rate of 53.45%. Abnormalities in repeated nerve stimulation tests were observed in 33.33% of the patients. The antibody-positive group exhibited a higher frequency of progression to generalized myasthenia gravis (p = 0.011) and a higher incidence of chest abnormalities (p &lt; 0.001) compared to the antibody-negative group. Horizontal and vertical diplopia were commonly observed in a complex group of patients with diplopia and blepharoptosis (p &lt; 0.001); there was a difference in the pattern of strabismus between the diplopia single group with esotropia and the complex group with exotropia (p = 0.029). In addition, the combination group demonstrated a higher antibody titer (p = 0.034), a higher frequency of abnormalities in repeated nerve stimulation tests (p = 0.022), and a higher incidence of chest abnormalities (p = 0.022).Conclusions: The anti-acetylcholine receptor antibody-positive group had a higher incidence of progression to generalized myasthenia gravis; moreover, the complex group of patients with diplopia and ptosis exhibited elevated levels of anti-acetylcholine receptor antibodies and frequently accompanied both horizontal and vertical strabismus.

Pre-Operative Ocular Findings and Long-Term Follow-Up in a Large Cohort of Non-Syndromic Unicoronal Craniosynostosis.

(1) Background: Non-syndromic unicoronal craniosynostosis (UCS) is associated with a high prevalence of ocular anomalies. Currently, the etiology of this association remains obscure, however, it is presumed to be primarily attributed to their orbital malformations and/or secondary to craniofacial surgery. We assessed pre-operative ophthalmological examinations of non-syndromic UCS patients and compared them with their postoperative outcomes and long-term follow-up. (2) Methods: A retrospective case series was conducted on medical records of patients with non-syndromic UCS at Sophia Children's Hospital, Rotterdam. Ophthalmologic examinations were collected at different time periods: T1 (first visit), T2 (<1 year after cranioplasty), and T3 (long-term follow-up at last visit). The McNemar's test was used for statistical analysis. (3) Results: A total of 101 patients were included, for whom examinations were available at T1 and T3. Patients had a mean age of 2.8 years (±2.7) and 9.5 (±4.9) at T1 and T3, respectively. At T1, 52 patients (51.5%) were diagnosed with strabismus, and 61 patients (60.4%) at T3. Vertical strabismus increased significantly from 23 patients (22.8%) at T1 to 36 patients (35.6%) at T3 (p = 0.011). Followed by astigmatism, which increased significantly from 38 (37.6%) at T1 to 59 (58.4%) patients at T3 (p = 0.001). T1 was available in 20 patients prior to fronto-orbital advancement (FOA), therefore, a sub-analysis was conducted on these patients, which was followed shortly after FOA at T2. Prior to FOA, strabismus was present in 11 patients (55.0%) and in 12 patients (60.0%) at T2. After FOA, strabismus worsened in two patients. (4) Conclusions: This study showed the high prevalence of ocular anomalies in patients with non-syndromic UCS before and after cranioplasty and at long-term follow-up. The findings of this study show that ophthalmic and orthoptic examinations are an important part of the optimal treatment of patients with non-syndromic UCS.

Characteristics of Guyton's exaggerated forced duction test (FDT) and torsional FDT in congenital superior oblique palsy

Objective: To investigate the characteristics of Guyton's exaggerated forced duction test (FDT) and torsional FDT in patients with congenital superior oblique palsy (CSOP) and their correlation with clinical features. Methods: This cross-sectional study included single-eye CSOP patients and intermittent exotropia (IXT) patients scheduled for strabismus correction surgery at Tianjin Eye Hospital from September 2021 to March 2022. Prior to surgery, measurements of fovea-disc angle (FDA) and maximum cross-sectional area of the superior oblique muscle (max-CSA) were obtained in both eyes of the patients. The Guyton's exaggerated FDT and torsional FDT were performed intraoperatively to assess the degree of superior oblique muscle relaxation. The characteristics of the two FDT tests and their correlation with vertical strabismus angle, FDA, and max-CSA were analyzed. Statistical analyses were conducted using t-test, ANOVA, Tukey's test, Mann-Whitney U test, and chi-square test. Results: A total of 42 patients (84 eyes) were included in the study, including 19 IXT patients (38 eyes) and 23 CSOP patients (46 eyes, 23 eyes with palsy and 23 eyes without palsy). There were no statistically significant differences in gender composition or age between the IXT and CSOP patients (all P>0.05). The degrees of superior oblique muscle relaxation measured by the Guyton's exaggerated FDT were (-2.52±1.20), (-0.35±0.71), and (-0.03±0.16) for the palsy eye, non-palsy eye, and IXT eyes, respectively, showing significant differences (F=88.10, P<0.001). The torsional FDT measurements yielded external rotation angles of 48.70°±9.67°, 37.39°±5.40°, and 38.95°±2.88° for the palsy eye, non-palsy eye, and IXT eyes, respectively, showing significant differences (F=16.67, P<0.001). There was no statistically significant difference in internal rotation angles (F=2.36, P=0.100). The FDA values were-12.11°±7.42° for IXT patients and-19.02°±4.95° for CSOP patients, while the max-CSA values for the palsy eye and non-palsy eye of CSOP patients were (7.59±4.69) mm² and (11.63±3.64) mm², respectively, all showing significant differences (all P<0.001). The degree of superior oblique muscle tendon relaxation assessed by the Guyton's exaggerated FDT was negatively correlated with the external rotation angle measured by the torsional FDT (r=-0.64, P=0.001). They were positively correlated with max-CSA (r=0.45, P=0.030) and negatively correlated with max-CSA (r=-0.52, P=0.011). However, there was no correlation with vertical and rotational strabismus angle (r=-0.12, P=0.579; r=0.33, P=0.126) and FDA (r=-0.02, P=0.921; r=-0.23, P=0.309). Conclusions: Guyton's exaggerated FDT and torsional FDT can both assess the degree of superior oblique muscle relaxation in patients with CSOP. Furthermore, these two tests are correlated with changes in superior oblique muscle morphology. However, FDT cannot reflect the degree of vertical and rotational strabismus in patients.

Prevalence of cervical postural alterations in oculomotor disturbances: a Brazilian cohort study

The literature suggests that maintaining correct posture depends on a balance between orientation and balance, which is linked to the reflex relationship between the oculomotor system and the superior cervical spine. Any disruption to this relationship can cause postural deviation, as the posture is dependent on head balance and eye horizontality. This study aimed to investigate the prevalence of cervical posture alterations, such as head tilt, rotation, and protrusion, scapular waist changes, scoliosis, kyphosis, and lumbar hyperlordosis, in patients with oculomotor disturbances, including convergent, divergent, and vertical squint, and convergence insufficiency. The study evaluated 24 patients aged between 4 and 39 years old, both male and female, through ocular motility and postural examination. The results showed that all patients with oculomotor disturbances also had postural imbalances, and the percentage of alterations in the posture segments was high. Therefore, oculomotor disturbances can cause postural imbalance, leading to orthopedic and facial asymmetry. The study concluded that patients with oculomotor disturbances should be evaluated to determine the compensatory positions they adopt and set a better visual performance that does not alter their appearance in the long term.