Ocular Tilt Reaction Research Articles

Pearls & Oy-sters: INO Plus From Downward Herniation-A Cautionary Tale Regarding Neuro-Ophthalmologic Signatures of Brainstem Compression.

Pupillary assessment is a quintessential part of the clinical examination in neuro-intensive care patients because it provides insight into the integrity of midbrain reflex arcs. Abnormal pupils, particularly anisocoria and later bilateral fixed mydriasis, are classically used to assess expansive intracranial processes because they are frequently considered early indicators of transtentorial midbrain compression due to elevated intracranial pressure. Complex ocular motor deficits mapping to the midbrain are rarely described in the setting of high transtentorial pressure. This is likely because ocular motor deficits typically occur in conjunction with decreased consciousness and corticospinal tract dysfunction reflecting advanced midbrain compromise. We present a case of left midbrain compression due to downward herniation in a patient with acute-on-chronic bilateral subdural hematoma. Ocular motor assessment demonstrated left internuclear ophthalmoplegia (INO) and an ocular tilt reaction, termed INO plus. However, pupillary, mental status, and sensorimotor examinations were unremarkable. Head magnetic resonance imaging revealed acute perforator ischemia in the left pontomesencephalic tegmentum, localizing to the ipsilateral medial longitudinal fasciculus and graviceptive oculocephalic circuits. Microvascular compromise secondary to mechanical pressure is discussed as a causative mechanism. We caution against overreliance on "telltale pupils" in suspected brainstem compression and recommend checking for other oculomotor signs.

Complete ocular tilt reaction with subjective visual vertical tilt in a patient with a medial prefrontal cortex lesion: a case report

A 61-year-old male patient undergoing chemotherapy for esophageal cancer presented with symptoms of rightward tilting while both sitting and walking. A neurological examination revealed a head tilt, skew deviation with hypertrophy of the left eye, and a rightward shift in his gait. No spontaneous nystagmus was observed, and the vestibulo-ocular reflex was normal. Magnetic resonance imaging of the head revealed a suspected metastatic lesion in the right medial prefrontal cortex. Following the initiation of levetiracetam treatment, the patient demonstrated marked improvement, with the resolution of both head tilt and skew deviation within 1 month. Traditionally, the ocular tilt reaction has been attributed to unilateral or asymmetric dysfunction of the graviceptive pathways extending from the utricle to the upper midbrain lesions. However, this case highlights the potential involvement of the prefrontal cortex in the ocular tilt reaction. Further research is warranted on the role of the prefrontal cortex within the vestibular system.

Skew deviation and ocular tilt reaction as presenting feature of CACNA1A mutation

We report the case of a 9-year-old girl with aggravation of childhood left head tilt without diplopia. She had right hypertropia and right incyclotorsion, which was compatible with skew deviation and ocular tilt reaction (OTR). She had ataxia, epilepsy, and cerebellar atrophy. Her OTR and neurologic dysfunctions were secondary to a channelopathy caused by CACNA1A mutation.

Ocular counter-roll during a Mŕnière’s attack: evidence of ictal utricle pathway imbalance using fundus photography (P3-9.004)

<h3>Objective:</h3> To call attention to unrecognized ictal vestibular manifestations of Mŕnière’s disease. <h3>Background:</h3> During Mŕnière’s disease (MD) attacks, static semicircular canal (SCC) asymmetry causes spontaneous nystagmus (ipsilesional when excitatory, and contralesional when inhibitory). Acute dynamic SCC dysfunction can cause an abnormal head impulse test (HIT, e.g., acute vestibular neuritis), although the HIT can be normal during a MD attack. Documentation of ictal otolith (utricle and saccule) dysfunction using vestibular evoked myogenic potentials (VEMPs) has rarely been reported. We describe the first case, to our knowledge, of a patient presenting with a Mŕnière’s attack in whom an ocular counter-roll (OCR, from static utricle pathway imbalance) was documented using fundus photography. <h3>Design/Methods:</h3> One case report of a patient with an OCR observed during a MD attack. <h3>Results:</h3> A 65-year-old man with known history of bilateral MD presented during a typical vertigo attack, and testing demonstrated: 1) Video-oculography (VOG) – spontaneous horizontal-torsional, unidirectional right beating nystagmus, following Alexander’s law; 2) Video HIT (vHIT) – low gain (0.49 where &lt;0.7 is considered abnormal) in the plane of the left horizontal SCC; 3) fundus photography – OCR with the top poles of both eyes rotated toward the left ear, in the absence of other features of the ocular tilt reaction (OTR, including OCR, head tilt, skew deviation). The HINTS exam (head impulse, nystagmus, test of skew) suggested a left peripheral vestibulopathy, and a Mŕnière’s attack was diagnosed given his history. Three weeks later testing was repeated while asymptomatic: 1) VOG – no nystagmus; 2) vHIT – normal horizontal SCC gain (0.73); 3) fundus photography – no OCR. For more, visit the NOVEL collection: https://collections.lib.utah.edu/ark:/87278/s6k97g27 <h3>Conclusions:</h3> Using a non-mydriatic fundus camera, we were able to document an ictal OCR in MD. Its presence suggested utricle pathway imbalance, offering insight into the labyrinthine structures that may be involved during a MD attack. <b>Disclosure:</b> Dr. Fracica has nothing to disclose. Dr. Gold has received personal compensation in the range of $500-$4,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Springer .

Contraversive Ocular Tilt Reaction, Body Lateropulsion and Gaze-Evoked Nystagmus After Inferior Cerebellar Peduncle and Dentate Nucleus Stroke

Contraversive Ocular Tilt Reaction, Body Lateropulsion and Gaze-Evoked Nystagmus After Inferior Cerebellar Peduncle and Dentate Nucleus Stroke

Visual Fixation-Induced Hemi-Seesaw Nystagmus

Seesaw nystagmus (SSN) is characterized by conjugate torsional nystagmus with opposite vertical components in the two eyes. The waveform may be pendular or jerk (hemi-seesaw nystagmus, HSSN), in which the slow phase corresponds to one half-cycle and the quick phase to the other. Pendular SSN and HSSN have distinct clinical presentations and underlying causes. The pathophysiology of pendular SSN may be instability of visuovestibular interactions, while the underlying mechanism for HSSN may be related to the ocular tilt reaction or an imbalance in vestibular pathways. We report a patient with HSSN due to unilateral mesodiencephalic infarction that becomes apparent during visual fixation only.

The diagnostic value of the ocular tilt reaction plus head tilt subjective visual vertical (±45°) in patients with acute central vascular vertigo.

To investigate the localization diagnostic value of the ocular tilt reaction (OTR) plus head tilt subjective visual vertical (SVV) in patients with acute central vascular vertigo (ACVV). We enrolled 40 patients with acute infarction, 20 with unilateral brainstem infarction (BI) and 20 with unilateral cerebellar infarction (CI). We also included 20 patients with unilateral peripheral vestibular disorders (UPVD) as the control group. The participants completed the OTR and SVV during head tilt (±45°) within 1 week of symptom onset. In patients with ACVV, including that caused by lateral medullary infarction (100%, 2/2), partial pontine infarction (21%, 3/14), and cerebellum infarction (35%, 7/20), we observed ipsiversive OTR, similar to that seen in UPVD patients (80.0%, 16/20). Some of the patients with medial medullary infarction (50%, 1/2), partial pons infarction (42%, 6/14), midbrain infarction (100%, 2/2), and partial cerebellum infarction (30.0%, 6/20) showed contraversive OTR. The skew deviation (SD) of the BI group with ACVV was significantly greater than that of the UPVD group (6.60 ± 2.70° vs. 1.80 ± 1.30°, Z = -2.50, P = 0.012), such that the mean SD of the patients with a pons infarction was 9.50° and that of patients with medulla infarction was 5.00°. In ACVV patients with no cerebellar damage, the area under the curve of the receiver operating characteristic curve corresponding to the use of SD to predict brainstem damage was 0.92 (95%CI: 0.73-1.00), with a sensitivity of 100% and a specificity of 80% when SD ≥ 3°. We found no statistical difference in SD between the UPVD and CI groups (1.33 ± 0.58° vs. 1.80 ± 1.30°, Z = -0.344, P = 0.73). Compared with the UPVD patients, the ACVV patients with a partial pons infarction (43%, 6/14, χ2 = 13.68, P = 0.002) or medulla infarction (25%, 1/4, χ2 = 4.94, P = 0.103) exhibited signs of the ipsiversive E-effect with the contraversive A-effect, while those with a partial medulla infarction (50%, 2/4), pons infarction (43%, 6/14), or cerebellar infarction (60%, 12/20) exhibited a pathological symmetrical increase in the E-effect. The evaluation of OTR plus head tilt SVV (±45°) in vertigo patients is helpful for identifying and diagnosing ACVV, especially when SD is ≥ 3° or the E-effect is symmetrically increased.

NCMP-10. NEURO-OPHTHALMOLOGICAL FINDINGS IN CHILDREN AND ADOLESCENTS WITH MEDULLOBLASTOMA - A RETROSPECTIVE ANALYSIS

Abstract BACKGROUND Medulloblastoma represents the most common malignant pediatric brain tumor. Ophthalmic complications are possible sequelae. METHODS Pediatric medulloblastoma (MB) patients treated at the Medical University of Vienna from January 2012 to August 2021 were analyzed and their last ophthalmic assessment was reviewed. RESULTS Fifty-six MB patients could be included (71.4% non-WNT/non-SHH, 16.1% SHH-activated, 8.9% WNT-activated, 3.6% non-specified). Mean age at diagnosis was 7.2 years (range 0-19). Median follow-up to last ophthalmological assessment was 19.7 months (range 0.1-93.2). Thirty-four children underwent tumor resection at our hospital, their tumor localizations were: vermis (55.9%), floor of the 4th ventricle (26.5%), cerebellar hemispheres (11.8%), lateral recess (5.9%). Symptoms at presentation were evaluable for 51 children: 92.2% had symptoms of elevated intracranial pressure, 76.5% ataxia and 21.6% visual disturbances. Postoperative posterior fossa syndrome was observed in 11.1% of 54 children. 98.2% had chemotherapy as part of their initial treatment and all children older than four years (85.7%) received postoperative irradiation of the posterior fossa. In 13 (23.2%) intraventricular chemotherapy was applied. At the last follow-up 21 patients experienced relapse after primary treatment. At the final assessment, frequent neuro-ophthalmological abnormalities included: oculomotor disturbance (75%), esotropia (35.7%) including abducens palsy (12.5%), other cranial nerve palsies (21.4%), horizontal gaze-evoked nystagmus (51.8%), spontaneous nystagmus (16.1%), ocular tilt reaction (21.4%), and optic disc abnormalities (14.3%). Good visual acuity (≥20/25) was maintained in 62.5% patients. Visual field and optical coherence tomography was successfully performed in 75% and 66.1% of patients, respectively. Optic pathway lesions were detected in 4 patients (7.1%), including two cases with occipital metastases, one with optic nerve metastasis and one with leptomeningeal carcinomatosis. Orthoptic treatment with prisms and strabismus surgery was required in 14.3% and 7.7% of children, respectively. CONCLUSION Children with MB frequently suffer from neuro-ophthalmological late-effects. Regular monitoring is warranted to initiate appropriate management.

Diagnosing and localizing the acute vestibular syndrome – Beyond the HINTS exam

When assessing the acutely dizzy patient, the HINTS ‘Plus’ (Head Impulse, Nystagmus, Test of Skew, ‘Plus’ a bedside assessment of auditory function) exam is a crucial component of the bedside exam. However, there are additional ocular motor findings that can help the clinician distinguish peripheral from central etiologies and enable accurate localization, especially when the patient has acute dizziness, vertigo and/or imbalance but without spontaneous nystagmus. We will review the literature on these findings which are ‘beyond HINTS’ and include saccades/ocular lateropulsion, smooth pursuit, and provocative maneuvers including head-shaking and positional testing (not part of the HINTS exam). Additionally, we will expound on the localizing value of nystagmus, ocular alignment and the ocular tilt reaction (parts of the HINTS exam). The paper has been organized neuroanatomically, based on brainstem and cerebellar structures that have been reported to cause the acute vestibular syndrome.

Evaluation, causes and management of acute spontaneous dizziness

Although acute dizziness is a very frequent reason for admissions to emergency care, its differential diagnosis is difficult to establish due to many factors. Dizziness may mean diverse sensations such as vertigo, lightheadedness, presyncope, disequilibrium, or simply feeling unwell. The classical approach to dizziness initiates with characterizing the form of dizziness according to the belief that every kind of dizziness represents a particular underlying etiology: vertigo is vestibular, presyncope is cardiovascular, disequilibrium is neurological, and nonspecific dizziness is psychogenic or metabolic. Development of acute dizziness/vertigo unaccompanied by precipitating features occurs in patients of acute spontaneous dizziness. The dizziness/vertigo mainly presents with autonomic symptoms like imbalance, nausea, and vomiting. Dizziness/vertigo and imbalance are the commonest manifestations in vertebrobasilar ischemia, which accounts for over 20% of all ischemic strokes. It is essential to distinguish between isolated vascular vertigo from less severe disorders related to the inner ear as the treatment plan and prognosis vary among these problems. The development of diffusion-weighted magnetic resonance imaging (MRI) has improved the infarction identification in cases with vascular dizziness/vertigo, particularly from undermined posterior blood flow. Nonetheless, proper bedside neurotologic assessment which includes components such as head impulse/thrust test, head shaking nystagmus test and ocular tilt reaction test demonstrate higher sensitivity than imaging in diagnosing acute cerebrovascular accidents as an etiology of abruptly occurring vertigo lasting longer than one day, particularly in the initial 48 hours.

A Novel Variant of the Short-Chain Enoyl-CoA Hydratase-1 Gene Presenting with a Mild Phenotype: The Second Case Report from India

AbstractA 9-year-old girl presented with asymmetric abnormal twisting movements affecting her left side more than the right side, initially action induced, but later persistent. Examination revealed generalized persistent dystonia with choreoathetosis and right partial tonic ocular tilt reaction. Brain magnetic resonance imaging showed T1 and T2 fluid-attenuated inversion recovery (FLAIR) hypointense and T2 hyperintense signal changes in bilateral globus pallidi. Clinical exome sequencing revealed compound heterozygous variatnts in enoyl-CoA hydratase-1 (ECHS1) gene: a novel pathogenic variant in exon 6, chr10:g.133366045G &gt; A (p.Gln224Ter) and a likely pathogenic variant in exon 5, chr10:g.133366990G &gt; A (p.Ala173Val). Metabolic testing and arterial lactate levels were normal. She was treated with valine restricted diet, trihexiphenidyl, clonazepam, N-acetyl cysteine and mitochondrial cocktail, without significant improvement over the 6 months follow-up period.

Pearls & Oy-sters: Vertical Diplopia and Ocular Torsion: Peripheral vs Central Localization.

We describe a case with torsional deviation of the eyes from a brainstem lesion. Torsional eye movement refers to changes in the position of the eyes in the roll plane around the visual axis. When the head is tilted laterally (that is, rolled toward the shoulder), the eyes roll in the opposite direction as part of the torsional vestibulo-ocular reflex known as the ocular counter-roll. Pathologies that affect the otolith-ocular pathway can lead to a torsional deviation of the eyes as part of the ocular tilt reaction (OTR) that also causes vertical deviation of the eyes (skew deviation) and head tilt. Lesions caudal to the pontomedullary junction (such as the labyrinth, eighth cranial nerve, or vestibular nucleus) result in an OTR with ipsiversive torsional deviation, whereas lesions rostral to the junction result in an OTR with contraversive torsional deviation. Furthermore, torsional deviation of the eyes in the OTR is conjugate (incyclotorsion in the higher eye and excyclotorsion in the lower eye), whereas torsional deviation from ocular palsy in peripheral lesions is disconjugate (e.g., exyclotorsion only in the higher eye with superior oblique palsy). Therefore, the pattern of torsional eye deviation can be helpful in localizing the lesion. Several techniques including fundus photography, double Maddox rod testing, optical coherence tomography, and video-oculography are used to measure torsional eye position.

Current-dependent ocular tilt reaction in deep brain stimulation of the subthalamic nucleus: Evidence for an incerto-interstitial pathway?

The aim was to characterize a combined vestibular, ocular motor and postural syndrome induced by deep brain stimulation (DBS) of the subthalamic nucleus in a patient with Parkinson's disease. In a systematic DBS programming session, eye, head and trunk position in roll and pitch plane were documented as a function of stimulation amplitude and field direction. Repeat ocular coherence tomography was used to estimate ocular torsion. The interstitial nucleus of Cajal (INC), zona incerta (ZI) and ascending vestibular fibre tracts were segmented on magnetic resonance imaging using both individual and normative structural connectomic data. Thresholded symptom-associated volumes of tissue activated (VTA) were calculated based on documented stimulation parameters. Ipsilateral ocular tilt reaction and body lateropulsion as well as contralateral torsional nystagmus were elicited by the right electrode in a current-dependent manner and subsided after DBS deactivation. With increasing currents, binocular tonic upgaze and body retropulsion were observed. Symptoms were consistent with an irritative effect on the INC. Symptom-associated VTA was found to overlap with the dorsal ZI and the ipsilateral vestibulothalamic tract, while lying rather distant to the INC proper. A ZI-to-INC 'incerto-interstitial' tract with contact to the medial-uppermost portion of the VTA could be traced. Unilateral stimulation of INC-related circuitry induces an ipsilateral vestibular, ocular motor and postural roll-plane syndrome, which converts into a pitch-plane syndrome when functional activation expands bilaterally. In this case, tractography points to an incerto-interstitial pathway, a tract previously only characterized in non-human primates. Directional current steering proved useful in managing this rare side effect.

Spontaneous Resolution of Ocular Tilt Reaction

A 30-year-old man presented to the ophthalmologic clinic with sudden onset of vertical and torsional diplopia. Concomitant skew deviation with right hypertropia was observed. Funduscopy revealed that the fovea was located above the lower edge of the optic disc in the right eye; incyclotorsion was present. Conversely, the fovea was located below the lower edge of the optic disc in the left eye; excyclotorsion was present. He was diagnosed to have ocular tilt reaction (OTR). Neurological examination was unremarkable. Cranial magnetic resonance imaging demonstrated no abnormalities and no evidence of acute ischemia, demyelination, or vestibular nerve abnormality. The patient was followed without any treatment. One month later, his diplopia had disappeared. Incyclotorsion in the right eye and excyclotorsion in the left eye were also improved. Torsional deviation is difficult to detect with a standard eye exam. A fundus photograph is useful for diagnosis in such cases if it can be obtained.

Central Ocular Motor Disorders: Clinical and Topographic Anatomical Diagnosis, Syndromes and Underlying Diseases.

The key to the diagnosis of ocular motor disorders is a systematic clinical examination of the different types of eye movements, including eye position, spontaneous nystagmus, range of eye movements, smooth pursuit, saccades, gaze-holding function, vergence, optokinetic nystagmus, as well as testing of the function of the vestibulo-ocular reflex (VOR) and visual fixation suppression of the VOR. This is like a window which allows you to look into the brain stem and cerebellum even if imaging is normal. Relevant anatomical structures are the midbrain, pons, medulla, cerebellum and rarely the cortex. There is a simple clinical rule: vertical and torsional eye movements are generated in the midbrain, horizontal eye movements in the pons. For example, isolated dysfunction of vertical eye movements is due to a midbrain lesion affecting the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), with impaired vertical saccades only or vertical gaze-evoked nystagmus due to dysfunction of the Interstitial nucleus of Cajal (INC). Lesions of the lateral medulla oblongata (Wallenberg syndrome) lead to typical findings: ocular tilt reaction, central fixation nystagmus and dysmetric saccades. The cerebellum is relevant for almost all types of eye movements; typical pathological findings are saccadic smooth pursuit, gaze-evoked nystagmus or dysmetric saccades. The time course of the development of symptoms and signs is important for the diagnosis of underlying diseases: acute: most likely stroke; subacute: inflammatory diseases, metabolic diseases like thiamine deficiencies; chronic progressive: inherited diseases like Niemann-Pick type C with typically initially vertical and then horizontal saccade palsy or degenerative diseases like progressive supranuclear palsy. Treatment depends on the underlying disease. In this article, we deal with central ocular motor disorders. In a second article, we focus on clinically relevant types of nystagmus such as downbeat, upbeat, fixation pendular, gaze-evoked, infantile or periodic alternating nystagmus. Therefore, these types of nystagmus will not be described here in detail.

Clinical and Imaging Profile of Patients with Joubert Syndrome.

ObjectiveJoubert syndrome (JS) is a rare syndrome characterized by ataxia and the molar tooth sign (MTS) on imaging. The present study aims to explore the clinical and radiological features in a cohort of patients with JS.MethodsThis was a retrospective chart review of patients with JS evaluated by movement disorder specialists.ResultsNine patients were included in the study. All patients had facial dysmorphism and ocular abnormalities, and 4 patients had dystonia. Ocular tilt reaction and alternate skew deviation (66%) were the most common ocular abnormalities. Horizontally aligned superior cerebellar peduncles were observed in all four patients with diffusion tensor imaging, with a lack of decussation in three. Exome sequencing performed in four patients revealed novel variants in the MKS1, CPLANE1, and PIBF1 genes.ConclusionFacial dysmorphism, ocular abnormalities and classical imaging findings were observed in all patients with JS. Apart from ataxia, dystonia and myoclonus are other movement disorders observed in JS.

Central positional nystagmus in inferior cerebellar peduncle lesions: a case series.

We aimed to characterize the central positional nystagmus (CPN) observed in lesions involving the inferior cerebellar peduncle (ICP). We analyzed the clinical and neurotologic findings in six patients with an isolated unilateral ICP infarction that had been diagnosed at a university hospital in South Korea from 2003 to 2019. Patients usually presented with acute vestibular syndrome in isolation (4/6, 67%). Ipsilesional spontaneous nystagmus was observed in five while supine (5/6, 83%). Four (4/6, 67%) patients showed CPN which included apogeotropic (n = 3) or geotropic (n = 1) during head turning to either side while supine, and vertical nystagmus during straight-head hanging, Dix-Hallpike maneuvers, or up-righting (n = 3). Four patients showed contraversive ocular tilt reaction or tilt of the subjective visual vertical. Bedside and video head-impulse tests were normal in all patients. CPN is a usual finding in ICP lesions, and may be ascribed to damage of the fibers running from the nodulus/uvula onto the vestibular nucleus via the ICP.

Analysis of the Skew Deviation to Evaluate the Period of Onset of a Canalolithiasis After Macular Damage.

Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular end-organ disease, and it is one of the first causes of access to the emergency room. The moment of migration of the otoconial debris in a semicircular canal does not necessarily coincide with the moment of detachment of the debris themselves. Consequently, the paroxysmal positional vertigo could arise with a variable delay with respect to the mechanical damage suffered by the macula. The aim of this work is to try to identify objective criteria to establish whether a canalolithiasis is synchronous or diachronic to the damage. The analysis of skew deviation in the context of ocular tilt reaction in patients with canalolithiasis could provide useful information to understand if macular damage occurred at the origin of the disease and when the damage may have occurred. In this study, 38 patients with BPPV were analyzed based on the type of skew deviation that was presented. We found that if the eye on the side of the canalolithiasis is hypotropic the damage of the utriculus is likely recent (last 10 days), if it is hypertropic the damage is not recent (20 days before) and finally if the eyes are at the same height it could be an utricular damage in compensation (occurring the last 10–20 days) or a secondary labyrinth canalolithiasis, without associated utricular damage. Our results show that the evaluation of skew deviation in patients suffering from BPPV could be useful to evaluate: (a) if a positional paroxysmal nystagmus can be related to an previous relevant injury event (for example a head injury that occurred days before the crisis); (b) if it is a BPPV of recent onset or a re-entry of the debris into the canal.

HINTS Examination in Acute Vestibular Neuritis: Do Not Look Too Hard for the Skew.

An ocular tilt reaction (OTR) is a triad of a skew deviation, head tilt, and ocular counter-roll that can be partial or complete. An OTR can occur anywhere along the utriculo-ocular motor pathways from the labyrinth to the interstitial nucleus of Cajal but is almost always central in origin. In acute vestibular neuritis (AVN), case reports have described patients with an OTR due to AVN, although it is unclear whether this examination finding is common or rare. The vestibular and ocular motor features of 7 patients presenting with AVN are described. Each of the 7 patients presented with typical features of AVN, including contralesional unidirectional spontaneous nystagmus and an ipsilesional abnormal head impulse test, although each patient also had a complete OTR. None of the patients had vertical diplopia or a skew deviation that was measurable with alternate cover testing (i.e., abnormal "test of skew" according to the Head Impulse, Nystagmus, Test of Skew examination); however, all had a subtle 1 prism diopter hyperphoria that was only measurable with a Maddox rod test. Seven cases of typical AVN with an OTR are presented, and in the authors' experience, the presence of a subtle OTR is a common feature of AVN in these patients.

Contralesional subjective visual horizontal predicts endolymphatic hydrops

Background: The subjective visual horizontal (SVH) is a test of utricular function that assesses conjugate ocular torsion which is a component of the ocular tilt reaction (OTR). In unilateral destructive peripheral vestibular lesions, the OTR and so the SVH tilt is usually ipsiversive.Aims/objective: Our study aimed to profile the causes of a contraversive SVH tilt in patients with a confirmed unilateral peripheral vestibular deficit.Materials and methods: The clinical records, nystagmus and vestibular investigation characteristics of 52 patients with a unilateral canal paresis (CP) on caloric of ≥30%, a contraversive SVH tilt of ≥4 degrees and at least one pure tone audiometry were retrospectively analysed.Results: The most common diagnosis of patients (n = 39) with a contraversive SVH and ipsilesional CP was endolymphatic hydrops: 35 (67.3%) had Meniere’s disease (MD) and 4 (7.7%) had delayed endolymphatic hydrops (DEH). The remaining 13 (25%) of cases had other peripheral aetiologies or an unknown diagnosis. 16 (30.8%) patients had ictal spontaneous nystagmus at the time of SVH or caloric testing.Conclusions and significance: A contraversive SVH with unilateral CP suggests endolymphatic hydrops.