Torsion and clinical features in patients with acquired fourth cranial nerve palsy.

This retrospective study aimed to compare objective/subjective torsion and other clinical characteristics of patients with acquired trochlear nerve palsy. This study included 82 consecutive patients who were diagnosed with acquired fourth cranial nerve palsy between 2014 and 2021 and who were followed up for ≥ 6 months. The etiologies, ocular deviation, objective and subjective torsions were reviewed. The etiologies were classified as ischemic, traumatic, brain lesion, idiopathic, or other. The patients were classified into two groups according to the recovery state: full recovery and partial/no-recovery. We compared the torsion and clinical features based on the etiology and recovery state. The average age was 59.1 ± 11.1 years, and 58 (71.0%) of the patients were male. The most common cause was ischemic (n = 49, 59.7%) and other common causes included traumatic (n = 16, 19.5%), brain lesion (n = 8, 9.8%), idiopathic (n = 5, 6.1%) and others (n = 4, 4.9%). Of the 82 patients, 56 (68.3%) were assigned to the full recovery group, and 26 (31.7%) were assigned to the partial/no-recovery group. The average age and number of patients with ischemic causes of palsy were greater in the full recovery group (p = 0.026 and p < 0.000, respectively). The vertical deviation angle, tilted angle on the Lancaster red-green test (LRGT), proportion of patients who experienced subjective torsion on the LRGT, and head tilt were smaller in the full recovery group (p = 0.037, 0.042, 0.045, and 0.006, respectively). Ischemic trochlear nerve palsy, advanced age, a small deviation angle at the primary position, and few cases of excyclotorsion on LRGT were characteristic of the full recovery group of acquired unilateral trochlear nerve palsy patients.

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.

Effect of inferior oblique myectomy on ocular torsion according to the absence of the trochlear nerve in unilateral congenital superior oblique palsy.

OBJECTIVES: To evaluate the effect of inferior oblique (IO) myectomy on ocular torsion according to the absence of the trochlear nerve in unilateral congenital superior oblique palsy (UCSOP). METHODS: We retrospectively reviewed the clinical data of patients who had been diagnosed with UCSOP and underwent ipsilateral IO myectomy (n = 43). Patients were classified into the present and absent groups according to the absence of the trochlear nerve and superior oblique hypoplasia on magnetic resonance imaging (MRI). For quantitative analysis of ocular torsion, disc-fovea angles (DFA) were collected in both eyes using fundus photographs taken within three months before surgery and one month after surgery. RESULTS: DFA of the paretic eye did not differ according to the absence of the trochlear nerve (9.4±5.6° in the present group vs. 11.0±5.4° in the absent group, p = 0.508). However, the present group had a larger DFA in the non-paretic eye than the absent group (14.1±6.7° in the present group vs. 8.0±5.0° in the absent group, p = 0.003). The change of ocular torsion after IO myectomy in the paretic eye was -5.3±3.7° in the present group and -4.8±3.5° in the absent group, respectively (p = 0.801). In the non-paretic eye, the change in DFA was -1.5±3.0° in the present group, which was larger than that in the absent group (0.7±2.6°, p = 0.047). In the multivariate analysis, the change in DFA was correlated with only the preoperative DFA (standardized ß = -0.617, p<0.001 in the paretic eye, and standardized ß = -0.517, p<0.001 in the non-paretic eye). CONCLUSIONS: In the paretic eye, there was no significant difference in the change of ocular torsion between both groups, whereas in the non-paretic eye, the present group had a larger change in DFA after IO myectomy than the absent group. However, in the multivariable analysis, the change in ocular torsion was significantly correlated with preoperative excyclotorsion but not with the presence of the trochlear nerve itself.

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.

[CASE SERIES OF EARLY NEUROIMAGING IN PATIENTS WITH VASCULAR RISK FACTORS AND ISOLATED SIX CRANIAL NERVE PALSY, DEMONSTRATING THE DILEMMA OF EARLY IMAGING].

INTRODUCTION: There are various etiologies for isolated third, fourth and sixth cranial nerve palsies. The most common etiology in adults aged 50 years and older with vascular risk factors such as diabetes, hyperlipidemia, and hyperlipidemia, is microvascular ischemia. The role of early neuroimaging in older patients with vascular risk factors presenting with acute isolated ocular motor nerve palsy is controversial. AIMS: We present six cases of patients aged 50 years and older, with vascular risk factors, who suffered from acute isolated paralysis of the sixth nerve. All cases were diagnosed with a non-microvascular ischemia etiology. RESULTS: The identified etiologies included petroclival meningioma with involvement of the cavernous sinus, metastatic hepatoma, plasmacytoma, venous thrombosis, arterial-venous malformation and aneurysm. CONCLUSIONS: Despite the high cost and presumed low yield, early neuroimaging can change the clinical management in certain cases. DISCUSSION: Previous studies have found the yield of early neuroimaging in older vasculopathic patients with acute 4th or 6th cranial nerve palsies to be 1-15%. In spite of these reports, our cases demonstrate the need for early onset imaging in these cases.

Can Binocular Alignment Distinguish Hypertropia in Sagging Eye Syndrome From Superior Oblique Palsy?

Purpose: Although the three-step test (3ST) is typically used to diagnose superior oblique palsy (SOP), sagging eye syndrome (SES) has clinical similarities. We sought to determine if alignment measurements can distinguish unilateral SOP from hypertropia in SES. Methods: We studied hypertropic subjects who underwent surface-coil magnetic resonance imaging (MRI) demonstrating either SO cross-section reduction indicative of congenital or acquired palsy (SOP group) or lateral rectus muscle sag (SES group). Alignment was measured by Hess screen and prism-cover testing. Multiple supervised machine learning methods were employed to evaluate diagnostic accuracy. Rectus pulley coordinates were determined in SES cases fulfilling the 3ST. Results: Twenty-three subjects had unilateral SOP manifested by SO atrophy. Eighteen others had normal SO size but MRI findings of SES. Maximum cross-section of the palsied SO was much smaller than contralaterally and in SES (P < 2 × 10-5). Inferior oblique cross-sections were similar in SOP and SES. In both SOP and SES, hypertropia increased in contralateral and decreased in ipsilateral gaze and was greater in ipsilateral than contralateral head tilt. In SES, nine subjects (50%) fulfilled the 3ST and had greater infraplacement of the lateral than medial rectus pulleys in the hypotropic orbit. Supervised machine learning of alignment data distinguished the diagnoses with areas under the receiver operating curves up to 0.93, representing excellent yet imperfect differential diagnosis. Conclusions: Because the 3ST is often positive in SES, clinical alignment patterns may confound SES with unilateral SOP, particularly acquired SOP. Machine learning substantially but imperfectly improves classification accuracy.

Recurrent Painful Ophthalmoplegic Neuropathy with Unilateral Oculomotor and Trochlear Nerve Palsy in an 8-year-old Girl.

BACKGROUND: Recurrent painful ophthalmoplegic neuropathy (RPON) is a rare disorder with a unilateral headache accompanied by ipsilateral episodes of painful ocular cranial nerve neuropathy, which typically occurs in childhood. CASE REPORT: We report an 8-year-old female with four episodes of RPON involving unilateral third and fourth cranial nerves. Right eye exotropia and complete ptosis were detected on examination. Brain MRI images revealed right third nerve enhancement where it exits from the brainstem. She completely recovered after 5 weeks with the administration of prednisolone and indomethacin. DISCUSSION AND CONCLUSION: Due to the rarity of this condition in children, recurrent painful ophthalmoplegic neuropathy should be considered as a differential diagnosis of unilateral or bilateral painful ophthalmoplegia, particularly with a history of migrainous headache. Since it is a treatable entity, and repeated attacks may lead to permanent sequela, early intervention is crucial.

Masquerading Superior Oblique Palsy.

PURPOSE: We evaluated patients with hypertropia compatible with a diagnosis of superior oblique (SO) palsy to ascertain whether the 3-step test (3ST) can distinguish SO atrophy characteristic of trochlear nerve pathology from masquerading conditions. DESIGN: Prospective cross-sectional study. METHODS: In an academic practice, we performed quasi-coronal plane, surface coil magnetic resonance imaging in 83 patients clinically diagnosed with SO palsy. We evaluated alignment, SO cross-sectional area, SO contractility, and rectus muscle pulley positions. RESULTS: A total of 57 patients with mean age 39 years (SD = 21 years) had unilateral SO palsy manifested by SO atrophy (22 congenital and 35 acquired). There was normal SO size in 26 patients with an average age of 39 years (SD =16 years) considered masquerades (8 congenital and 18 acquired). Maximum palsied SO cross-section averaged 9.5 ± 3.8 mm2, less than 18.4 ± 3.9 mm2 contralaterally (P < 10-24). In masquerades, maximum hypertropic SO cross-section was 20.7 ± 3.1 mm2, which was not different from the hypotropic SO or the contralesional muscle in SO palsy. Head tilt testing in masquerades was indistinguishable from SO palsy. In SO palsy, central hypertropia averaged 13.2 ± 9.4Δ, increasing to 21.1 ± 14.0Δ in ipsilateral tilt, and decreasing to 4.3 ± 5.3Δ in contralateral tilt. In masquerades, central hypertropia averaged 13.1 ± 8.7Δ, and was 17.7 ± 11.1Δ in ipsilateral and decreasing to 4.9 ± 5.1Δ in contralateral tilt. Upright hypertropia was larger at 17.7 ± 9.9Δ in congenital than 12.0 ± 8.4Δ in acquired SO palsy (P = 0025) but was indistinguishable from congenital masquerades. Contractile change in SO cross-section was bilaterally similar in masquerades. Relevant coordinates of rectus pulleys were similar bilaterally in masquerades. CONCLUSIONS: The 3ST pattern characteristic of unilateral SO palsy may be mimicked in all respects by masquerades.

Spontaneous Recovery of Traumatic Unilateral Superior Oblique Palsy and Ocular Factors for Predicting Prognosis.

PURPOSE: This study evaluated the prognosis of patients with traumatic unilateral superior oblique palsy (SOP) and clinical factors associated with spontaneous resolution. METHODS: Medical records of patients with traumatic unilateral SOP who visited two hospitals (Yeungnam University Hospital and Daegu Catholic University Medical Center) between January 2015 and June 2020 were reviewed retrospectively. When traumatic unilateral SOP did not recover within at least 1 year of follow-up, no spontaneous resolution was considered. Both traumatic and ocular factors were evaluated to evaluate their association with spontaneous recovery. RESULTS: Fifty-nine patients (mean age, 52.6 years; 48 male patients) were enrolled in this study. The mean interval from trauma to initial presentation was 3.9 months. The mean vertical deviation at initial presentation was 6.34 ± 5.22 prism diopters (PD) (range, 0-25 PD). During the mean 24.1-month follow-up period, 28 patients (47.5%) achieved spontaneous resolution of SOP. Thirteen patients underwent surgical treatment for SOP. Vertical deviation <6 PD at the initial visit and low fundus torsion in the nonparetic eye and both eyes were significantly associated with spontaneous recovery (p < 0.05, logistic regression analysis). Traumatic factors, including the trauma type, presence of intracranial lesion, loss of consciousness, and Glasgow Coma Scale score, were not associated with spontaneous recovery. CONCLUSIONS: In this multicenter study, spontaneously recovery was achieved in 47.5% patients with traumatic unilateral SOP. Even mild head trauma can lead to permanent SOP. Ocular factors, including the angle of deviation and fundus torsion, may better predict spontaneous resolution than traumatic factors in patients with traumatic unilateral SOP.

Neuro-Behçe Disease Causing Nuclear/Fascicular Forth Nerve Palsy.

ABSTRACT: Neuro-Behçe disease (NBD) has a predilection for affecting the parenchyma of the upper brainstem; however, involvement of the fourth nerve nucleus or fascicle by NBD has not been previously described. We report a case of a young man with acute right fourth nerve palsy and history of Behçet disease with an enhancing lesion in the left caudal midbrain corresponding to the left trochlear nerve nucleus/fascicle. This is the first described case of NBD producing nuclear/fascicular fourth nerve palsy. It also demonstrates an important clinicoanatomical correlate of decussation of fourth nerve fibers to the opposite side after exiting the midbrain.

Vertical Comitance of Hypertropia in Congenital and Acquired Superior Oblique Palsy.

BACKGROUND: Ivanir and Trobe have claimed that hypertropia (HT) that is greater in upgaze than downgaze, or equal to it, is characteristic of decompensated congenital superior oblique (SO) palsy and never present in ischemic, traumatic, or tumorous SO palsy. The reliability of this claim was tested in patients with SO palsy confirmed by MRI demonstration of subnormal ipsilesional SO size. METHODS: Quasi-coronal, surface coil MRI was performed in target-controlled central gaze to identify patients with a unilateral reduction in SO cross section indicative of palsy. Nine patients gave an unequivocal history or had markedly increased vertical fusional amplitudes indicative of congenital onset (mean age 38 ± 16 years, SD). Seven patients had unequivocal acquired onset (age 47 ± 14 years and symptom duration 5.4 ± 4.8 years), including 2 with demonstrated trochlear Schwannoma and 5 with onset after severe head trauma. Fifteen patients had gradually progressive onset unequivocally not congenital yet not associated with any identifiable precipitating event (age 52 ± 20 years and symptom duration 13 ± 14 years). RESULTS: Maximum SO cross section averaged 8.6 ± 3.9 mm2 in congenital palsy, not significantly different from 11.3 ± 3.5 mm2 in acquired palsy (P = 0.08) either unequivocally or progressively acquired, but significantly less than about 19 mm2 contralesionally in SO palsy (P < 10-4). Although mean central gaze HT was greater at 20.6 ± 8.0Δ in 9 cases of congenital than that in 22 acquired cases at 11.4 ± 6.8Δ (P = 0.002), HT was 8.4 ± 16.3Δ less in upgaze than downgaze in congenital SO palsy and 3.7 ± 11.2Δ less in acquired SO palsy. In congenital palsy, 33% of patients had HT greater in upgaze than downgaze while in 67% HT was greater in downgaze (by up to 42Δ). In acquired SO palsy, HT was greater in upgaze than downgaze or equal to it in 8 cases (36%, P = 0.87, X2). In acquired SO palsy, HT was greater in upgaze than downgaze in 37% and greater in downgaze than upgaze in 59% of cases. The HT was equal in upgaze and centralgaze in no congenital and 3 acquired cases of SO palsy. Trends were similar in unequivocal acquired and progressive acquired (noncongenital) SO palsy (P > 0.4). CONCLUSIONS: Hypertropia is not characteristically greater in upgaze than downgaze in congenital SO palsy proven by SO atrophy on MRI. In fact, average HT is greater in downgaze than upgaze in both acquired and congenital palsy, sometimes strikingly so in the latter. The finding of HT greater in upgaze than downgaze, or equal to it, does not reliably indicate that SO palsy is congenital, nor does maximum SO cross section.

The spectrum and differential diagnosis of acquired ocular motor nerve palsies: a clinical study of 502 patients.

BACKGROUND: Ocular motor nerve palsies (OMNP) frequently cause patients to present in an emergency room. In the following study, we report the differential diagnosis of OMNP by use of magnetic resonance imaging (MRI) and CSF examination as a standard. METHOD: We performed a data analysis of N = 502 patients who presented with oculomotor, trochlear, and/or abducens nerve palsy in the emergency room of the Department of Neurology, University of Ulm, between January 2006 and December 2019. We report clinical and MRI scan findings in all patients; furthermore, the CSF of 398 patients has been analysed. RESULTS: Abducens nerve palsies were most common (45%), followed by palsies of the oculomotor (31%) (CNP III) and trochlear nerve (15%). Multiple OMNPs were seen in 9% of our cohort. The most common causes included inflammations (32.7%), space-occupying lesions, such as aneurysms or neoplasms (17.3%), diabetes mellitus (13.3%), and brainstem infarctions (11%). Still 23.4% of the patients could not be assigned to any specific cause after differential diagnostic procedures and were described as idiopathic. One of three patients with an inflammation and 39% of the patients with space-occupying lesions showed additional cranial nerve deficits. CONCLUSION: Inflammation and space-occupying processes were the most frequent causes of OMNP, although brainstem infarctions also play a significant role, in particular in CNP III. The presence of additional CNPs increases the probability of an inflammatory or space-occupying cause.

Clinical Characteristics for Predicting Recovery of Acquired Fourth Cranial Nerve Palsy.

BACKGROUND: Fourth cranial nerve palsy is the most common disease diagnosed in patients with vertical diplopia. Although it is reported to present a good prognosis, there are currently no agreed on prognostic factors that anticipate the recovery of the palsy other than the etiology. The purpose of this study was to investigate the prognostic factors of acquired fourth cranial nerve palsy. METHODS: The medical records of consecutive patients diagnosed with acquired unilateral fourth cranial nerve palsy from 2010 to 2020 and followed up for ≥6 months were retrospectively reviewed. The cause and degree of palsy, ocular deviation (horizontal, vertical, and cyclo), and fundus torsion were reviewed. The cause of palsy was classified as ischemic, traumatic, intracranial mass, others, or idiopathic. Patients were divided into 2 groups according to palsy recovery: complete recovery (group CR) or not CR (group NCR). The clinical characteristics of the 2 groups were compared, and the risk factors for incomplete recovery were investigated. RESULTS: Thirty-five patients (25 men) were included in the study. The average age was 55.94 ± 16.11 years. CR was achieved in 23 patients (65.7%), and the time to recovery was 3.91 ± 4.03 months. The most common cause was traumatic (40.0%), followed by ischemia (37.1%), intracranial mass (11.4%), others (8.6%), and idiopathic (2.9%). The degree of palsy and fundus torsion was significantly higher in group NCR (P = 0.010 and P = 0.001). Severe oculomotor limitation, large fundus torsion, and intracranial mass cause rather than ischemic cause indicated a higher risk of incomplete or no recovery (P = 0.016, P = 0.009, and P = 0.043). CONCLUSION: Identifying whether a patient has an intracranial mass, severe oculomotor limitation, or large fundus excyclotorsion may be useful for predicting the recovery of acquired unilateral fourth cranial nerve palsy.