Skew ocular deviation: a catastrophic sign on MRI of fetal glioblastoma

CASE REPORT: We report the prenatal observation of fetal ocular skew deviation in a case of a glioblastoma found prenatally at 33 weeks' gestation by MRI. The fetal MRI, obtained by half-Fourier single-shot turbo spin echo (HASTE) pulse sequences, showed a tumor (80 mm in maximum diameter) in the right deep cerebral hemisphere with extension to the mid-cranial fossa and tentorial hiatus in addition to severe hydrocephalus. On coronal MR images a vertical dysconjugated gaze was recognized. One week after the MRI, frequent delayed deceleration prompted an emergency cesarean section. The baby was born with left hemiparesis and central neurogenic hyperventilation, which evolved into decerebrate rigidity and apneustic breathing within 2 h. Post-mortem examination revealed a glioblastoma in the right deep hemisphere, a tumor with brain stem involvement, and transtentorial herniation. CONCLUSIONS: We suggest, therefore, that recognition of ocular skew deviation on fetal MR images would indicate brain stem involvement and poor postnatal prognosis. Early recognition of the catastrophic sign would lead to proper management.     

The role of ocular torsion in visual measures of vestibular function

This brief review highlights problems in the interpretation of results about perceived postural roll-tilt of human subjects undergoing roll-tilt around their naso-occipital axis, when visual stimuli are used as a means of indicating perception. The otolithic stimulus, which causes the changes in perceived posture, also causes the eyes to roll (or tort). In turn, the altered torsional position of the eye causes the perceived orientation of visual stimuli to change. Consequently, indicators of postural perception, which rely on visual stimuli, are a confounded combination of two factors; the person's perceived postural roll-tilt, and the effect of the otolithic stimulus on ocular torsional position. Consequently, setting of a visual stimulus do not permit direct unambiguous interpretation of a subject's perceived postural roll-tilt.     

Central processing of human ocular torsion analyzed by galvanic vestibular stimulation

We examined the dynamics of human ocular torsion (OT) responses to sinusoidal galvanic vestibular stimulation (GVS) (0.005-1.67 Hz). The tonic OT showed a lowpass characteristic with a time constant of 1.74 s and a gain of 0.93 deg/mA. In two subjects, nystagmus dominated the observable OT pattern at frequencies <0.1 Hz. The nystagmus slow phases showed an exponential trajectory with a time constant of 1.49 s. The dynamics of both tonic OT and torsional nystagmus in our study were similar to the dynamics of OT induced by rotation and linear acceleration found in the literature. We propose a model for the central processing of torsional eye movements that is based on a common neural integration of semicircular canal (SC) and utricular inputs as well as nystagmus bursts. The sensitivity of all vestibular afferents to GVS was derived to be 0.76 spikes/s/mA. SC effects on OT are at least 3.5 times higher than utricular effects.     

The diagnostic value of vestibular-evoked myogenic potential in patients with vestibular schwannoma

ObjectiveThis study examined the diagnostic value of the vestibular-evoked myogenic potential (VEMP) in comparison with the caloric test in patients with vestibular schwannoma (VS).MethodsData were retrospectively collected from 803 consecutive patients who visited our vertigo clinic and underwent vestibular tests. Amongst them, 78 patients were diagnosed as having untreated unilateral VS. VEMP was performed using click and short-tone burst stimulation. The caloric test was performed using ice water. The sensitivity and specificity of each test were evaluated.ResultsOf the 78 patients with VS, 63 had abnormal VEMPs as well as abnormal caloric responses. Of the 725 patients without VS, 382 had normal VEMPs and 416 had normal caloric responses. The sensitivity and specificity of VEMP were 80.8% (95% CI: 72.0–89.5%) and 52.7% (95% CI: 49.1–56.3%), respectively; those of the caloric test were 80.8% (95% CI: 72.0–89.5%) and 57.4% (95% CI: 53.8–61.0%), respectively.ConclusionsThe sensitivity and specificity of VEMP and the caloric test showed no significant differences.SignificanceIn patients with VS, although the specificity of VEMP was not very high, its sensitivity was high and comparable to that of the caloric test.     

Lateropulsion of the eyes — A localizing brainstem sign

Summary Lateropulsion of the eyes, a distinctive sign of disordered ocular motor control, is described in a series of patients with asymmetrical lesions of the pons- and the lateral medulla. Simple bedside tests elicited a consistent lateral bias of conjugate eye movements towards the side of the lesion in all cases.

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Zusammenfassung Lateropulsion der Augen ist ein Zeichen einer gestörten Kontrolle der Oculomotorik. Es wird bei einer Reihe von Patienten mit asymmetrischen Läsionen der Brücke und der seitlichen Medulla beschrieben. In allen Fällen konnte durch einfache Beobachtung am Krankenbett eine signifikante Tendenz der konjugierten Augenbewegungen zum Überwiegen auf die Seite der Läsion hin beobachtet werden.

     

脑干听觉诱发电位对进展性卒中的早期诊断价值

目的分析脑干听觉诱发电位在进展性卒中早期的变化及其对早期诊断的价值。方法应用诱发电位仪对发病24h内43例颈内动脉系统进展性卒中与非进展性卒中患者进行检测及对比分析。结果进展性卒中早期,起源于脑干的Ⅲ、V波异常率达62.79%,其异常主要以双侧V波PL及I-V波IPL的延长为主,与对照组比较,差异有统计学意义(P<0.01)。结论脑干听觉诱发电位可作为颈内动脉系统进展性脑卒中在临床症状、体征进展达到诊断标准前的一个有效的评估指标,有助于临床对进展性卒中进行早期的干预性治疗。     

Ocular tilt reaction due to an upper brainstem lesion: Paroxysmal skew deviation,torsion, and oscillation of the eyes with head tilt

A patient with a focal brainstem abscess in the region of the zona incerta developed a chronic oculocephalic dyskinesia in which paraoxysmal tonic skew deviation and torsion of the eyes were coupled with ocular oscillations and head tilt.     

前庭性偏头痛的眼震视图表现及诊断价值

目的比较前庭性偏头痛(VM)和健康受试者的眼震视图(VNG)表现,明确VNG检查在VM中的诊断价值.方法前瞻性连续纳入2018年8月至2019年8月在新乡医学院附属人民医院神经内科就诊的VM患者55例和体检中心健康受试者45例,所有患者及健康受试者在条件允许下行VNG检查,包括视动性试验(扫视试验、平稳跟踪试验、视动性试验)、前庭功能试验(温度试验、摇头眼震)、自发性眼震、诱发性眼震检查(静态位置性试验).采用χ^2检验比较两组之间VNG结果的差异.结果VM组与健康受试者组之间人口统计学差异无统计学意义(均P>0.05).扫视试验:VM组有17例(30.9%)异常,健康受试者组异常例数3例(6.7%;χ^2=9.091,P<0.05);平稳跟踪实验:VM组异常20例(36.4%),健康受试者组异常5例(11.1%;χ^2=8.418,P<0.05);视动性眼震检查:VM组异常例数24例(43.6%),健康受试者组异常例数6例(13.3%;χ^2=10.823,P<0.05);温度试验:VM组有13例(23.6%)异常,健康受试者组中异常2例(3.6%;χ^2=7.150,P<0.05);摇头眼震:VM组有11例(20.0%)异常,健康受试者组异常2例(3.6%;χ^2=5.295,P<0.05);自发性眼震检查:VM组中异常10例(18.2%),健康受试者组异常4例(8.9%;χ^2=1.775,P>0.05);静态位置性眼震检查:VM组共有22例(40.0%)异常,健康受试者组中共有7例异常(16.5%;χ^2=7.183,P<0.05).结论VM组的总VNG检查异常率高于健康受试者组,说明VNG检查有助于VM的诊断,且其表现提示VM患者中枢及外周均有损害的迹象.     

The correction of ocular artifacts: a topographic perspective.

OBJECTIVE: To evaluate the scalp topography of the potentials related to saccades and blinks. METHODS: The scalp topographies of the potentials associated with saccades and blinks were recorded in 60 subjects. The topographies were analyzed using both source components and attenuation factors, with each factor representing the fraction of the potential recorded in peri-ocular electrodes that contributes to the EEG recorded from a particular scalp location. RESULTS: Blinks and upward saccades generated potentials with very different topographies. Left and right saccades and up and down saccades generated equal but inverted fields except at peri-ocular locations where subtle inequalities occurred. The potentials associated with lateral saccades were consistently larger in female subjects than in male subjects. CONCLUSIONS: The differences in the scalp topographies between blinks and vertical saccades can be explained by the different ways in which they are generated. Blink potentials are caused by the eyelids sliding down over the positively charged cornea, whereas saccade potentials are caused by changes in the orientation of the corneoretinal dipole. Any compensation procedure for ocular artifacts must take into account the topographic differences between blinks and upward saccades.     

前庭阵发症脑干听觉诱发电位的特点

目的探讨前庭阵发症(VP)脑干听觉诱发电位(BAEP)的特点。方法对51例VP患者的BAEP结果进行回顾性分析。结果 BAEP异常者40例,异常率为78.4%。与Ⅰ-Ⅲ波峰间期正常的患者相比,Ⅰ-Ⅲ波峰间期延长的患者男性比例高(χ2=4.763,P=0.029),病程显著延长(t=2.469,P=0.021),而平均年龄差异无统计学意义。与Ⅲ-Ⅴ波峰间期正常的患者比较,Ⅲ-Ⅴ波峰间期延长的患者男性比例、平均病程、平均年龄差异均无统计学意义。与Ⅰ-Ⅲ波峰间期耳间差正常的患者比较,Ⅰ-Ⅲ波峰间期耳间差延长的患者病程相对较长(P=0.055),男性有增多趋势(P=0.058),但差异无统计学意义。结论 VP患者BAEP异常以Ⅰ-Ⅲ波峰间期延长为主,且以男性更多见。病程越长,蜗神经越易受累。     

中央静脉征在复发缓解型多发性硬化中的MRI特征及诊断价值

目的探讨中央静脉征(CVS)在复发缓解型多发性硬化(RRMS)中特征性的MRI表现及其在RRMS诊断中的价值。方法收集2017年1月至2019年3月北京天坛医院收治的临床确诊的复发缓解型MS(RRMS)患者33例、视神经脊髓炎谱系疾病(NMOSD)患者30例及脑小血管病(CSVD)患者26例,根据北美MS影像检查合作组发布的《中央静脉征诊断多发性硬化症及其临床评价共识声明》中CVS的诊断标准及排除标准进行阅片,比较各组患者出现CVS阳性率、病灶中出现CVS阳性率以及CVS分布部位的差异。采用受试者工作特征曲线(ROC)分析CVS对RRMS诊断及鉴别诊断的价值,并计算CVS阳性率的cut-off值。结果三组患者存在CVS的比例比较有统计学差异(P=0.007)。RRMS病灶CVS阳性率高于NMOSD病灶(44.9%比8.0%,P<0.01),CVS阳性率的cut-off值为16.5%时,其诊断RRMS的敏感度为78.9%,特异性为91.3%。RRMS患者CVS的分布以脑室旁(50.9%)为主,深部白质(20.7%)及近皮层(16.6%)次之,幕下较为少见(11.8%)。结论 CVS...     

Paroxysmal facial itch: a presenting sign of childhood brainstem glioma

Two children with neurofibromatosis and a chief complaint of severe, episodic, unilateral facial itching were found to have brainstem glioma. Initial computerized tomography of the brain was thought to be normal, but the brainstem tumor was subsequently demonstrated on magnetic resonance imaging. The paroxysmal facial itching resolved in both cases after a course of radiation therapy. The pathophysiology of the attacks of facial itching is unknown but must be related to the brainstem glioma. This is the first report of paroxysmal, unilateral facial itching as a presenting sign of childhood brainstem tumor.     

Oculogyric crisis: a syndrome of thought disorder and ocular deviation

In 3 patients who suffered oculogyric crises, mental changes accompanied upward deviation of the eyes. In 1 patient, whom we studied in detail, the mental disturbance consisted of a disorder of attention in which pathological fixation of a thought occurred. During the period of upward eye deviation, all functional types of conjugate eye movements were present in the upper field of gaze, suggesting an imbalance of the vertical gaze-holding mechanism. The eyes could be driven down only by a combined blink and downward saccade. Both the thought disorder and the ocular deviation responded promptly to anticholinergic agents. We propose that the disorders of thought and eye movement in oculogyric crisis are linked by a pharmacological imbalance common to both.     

Neural correlates of British sign language comprehension: spatial processing demands of topographic language

In all signed languages used by deaf people, signs are executed in "sign space" in front of the body. Some signed sentences use this space to map detailed "real-world" spatial relationships directly. Such sentences can be considered to exploit sign space "topographically." Using functional magnetic resonance imaging, we explored the extent to which increasing the topographic processing demands of signed sentences was reflected in the differential recruitment of brain regions in deaf and hearing native signers of the British Sign Language. When BSL signers performed a sentence anomaly judgement task, the occipito-temporal junction was activated bilaterally to a greater extent for topographic than nontopographic processing. The differential role of movement in the processing of the two sentence types may account for this finding. In addition, enhanced activation was observed in the left inferior and superior parietal lobules during processing of topographic BSL sentences. We argue that the left parietal lobe is specifically involved in processing the precise configuration and location of hands in space to represent objects, agents, and actions. Importantly, no differences in these regions were observed when hearing people heard and saw English translations of these sentences. Despite the high degree of similarity in the neural systems underlying signed and spoken languages, exploring the linguistic features which are unique to each of these broadens our understanding of the systems involved in language comprehension.     

Geotropic ocular deviation with skew and absence of saccade in Creutzfelt-Jakob disease.

Three patients with Creutzfelt-Jakob disease (CJD) showed characteristic ocular manifestations. The head was turned left or right with the eyes deviated downward and skewed. When the head was turned to one side, the eyes very slowly deviated to that side. In addition, spontaneous ocular movements were very slow with no saccadic component early in the apathetic stage. Caloric stimulation produced tonic deviation to the appropriate side without nystagmus. At autopsy one patient showed lesions compatible with the panencephalopathic type of CJD. Although bilateral pretectal areas had marked gliosis, other nuclei and structures associated with oculomotor system in the brainstem, including the oculomotor, trochlear, abducens, vestibular and perihypoglossal nuclei, medial longitudinal fasciculus and para-median pontine reticular formation were preserved. These patients had a supranuclear disorder, probably caused by combined disruption of the direct and indirect frontal eye field to the brainstem pathways plus impairment of the superior colliculus-mediated saccade pathways.     

4.0 Tesla magnetic resonance imaging of brainstem lesions with ocular motility deficits.

The authors studied six patients with brainstem ocular motility deficits with 4.0 Tesla (T) magnetic resonance imaging to investigate whether a higher field strength would produce superior images compared with 1.5T. In four patients whose lesions were evident on 1.5T, the increased signal-to-noise achieved with 4.0T allowed for better resolution at 1-mm slice thickness than was achieved at the standard 5-mm slice thickness with 1.5T. In the two patients with unremarkable 1.5T scan results, 4.0T also failed to demonstrate a lesion. Therefore, 4.0T imaging has superior resolution to 1.5T imaging and can provide more detailed images of lesions identified by 1.5T.     

Triggering essential head tremor with sustained phonation: A clinical phenomenon with potential diagnostic value

Here we report a clinical phenomenon that we have observed repeatedly in clinical research settings; namely, a triggering and/or exacerbation of head tremor during or immediately following sustained phonation. To our knowledge, it has not been reported previously nor has it been the subject of study. Here we: 1) report the phenomenon, 2) provide several visual illustrations, 3) estimate its prevalence, and 4) analyze its clinical correlates. Head tremor was assessed qualitatively, and scores were assigned pre-, during, and post-sustained phonation using the Tremor Research Group Essential Tremor Rating Assessment Scale. Seventy (68.6%) of 102 essential tremor (ET) patients exhibited a qualitative increase in head tremor amplitude during and/or immediately after sustained phonation; in 5 (4.9%), head tremor would not have been detected without the voice activation maneuver (i.e., it was not visible at any other point in the videotape aside from the period during/immediately following sustained phonation). Women were more likely than men to exhibit this phenomenon (p = 0.05), whereas age, age at onset, duration of tremor, and total tremor score did not predict responsiveness of head tremor to sustained phonation. Sustained voice activation is a useful examination maneuver that may elicit or amplify head tremor in ET. Head tremor is not reported to occur in patients with enhanced physiological tremor. Thus, this maneuver, by triggering head tremor, may be a useful diagnostic supplement, particularly in research/clinical settings where arm tremor is mild and the diagnosis (mild ET vs. enhanced physiological tremor) would otherwise be ambiguous.