Unilateral Midbrain Infarction Causing Upward and Downward Gaze Palsy

Vertikale Blickparesen bei dorsalem Mittelhirnsyndrom und anderen Erkrankungen

Hintergrund

Die vertikale Blickparese (vBP) ist ein typisches Symptom bei Läsionen des dorsalen Mittelhirns. Die klinische Ausprägung der vBP kann dabei stark variieren und im Rahmen eines dorsalen Mittelhirnsyndroms (DMS) mit zusätzlichen Symptomen wie einer Konvergenzparese, einem Konvergenzretraktionsnystagmus, einer verminderten Pupillenreaktion oder einer Skew Deviation vergesellschaftet sein. Je nach Lokalisation und Größe der Läsion kann auch eine Kombination mit weiteren zentralen Motilitätsstörungen vorliegen.

Material und Methode

Im Rahmen einer retrospektiven Studie wurden die Patientendaten unserer neuroophthalmologischen Ambulanz über einen Zeitraum von 25 Jahren nach Fällen mit Einschränkungen konjugierter vertikaler Augenbewegungen durchsucht und hinsichtlich ihrer neuroorthoptischen Befunde und Ätiologien ausgewertet.

Resultate

Es wurden 202 Patienten mit vBP identifiziert. Das Befundspektrum reichte von einer isolierten Sakkadenstörung nur nach oben bis hin zum kompletten Ausfall aller willkürlichen und reflektorischen vertikalen Augenbewegungen. Nur 12 vBP lagen isoliert vor. Ursächlich war bei 155 Patienten ein DMS, wovon aber nur 18 Fälle dem von Parinaud geprägten Syndrombild (vBP + Konvergenzparese ± Pupillenstörung ohne weitere Symptome) entsprachen; 42 Patienten mit DMS zeigten lediglich eine Sakkadenparese. Der Aufblick war bei DMS insgesamt mehr eingeschränkt als der Abblick. Die häufigsten Begleitsymptome waren eine Konvergenzparese (49 %), Konvergenznystagmus (40 %), Pupillenstörung (32 %), Skew Deviation (21 %) und Blickrichtungsnystagmus (15 %). In 58 Fällen traten weitere zentrale Okulomotorikstörungen auf. Bis zum 18. Lebensjahr war eine vBP bei 58 % der Patienten durch Gehirntumoren bedingt, wohingegen nach dem 60. Lebensjahr neben einem DMS durch Infarkte (41 %) v. a. degenerative Erkrankungen (44 %) ursächlich waren.

Schlussfolgerungen

Langsame und schnelle Augenbewegungen nach oben und unten werden im Hirnstamm unterschiedlich generiert, geleitet und integriert und können daher bei Läsionen des Mittelhirns verschieden stark gestört sein. Die Ergebnisse verdeutlichen zudem die enge Lagebeziehung der Zentren für vertikale Augenbewegungen, Konvergenz und Pupillenreaktion im dorsalen Mittelhirn. Die Kombination einer vBP mit weiteren neuroophthalmologischen Diagnosen kann daher eine topografische und ätiologische Zuordnung erleichtern.

An alternative mechanism of crossed vertical gaze palsy in unilateral mesodiencephalic infarction

Crossed vertical gaze palsy refers to a rare combination of elevation paresis in one eye and depression palsy in the fellow eye. It was once reported in a patient with unilateral infarction involving the mesodiencephalic junction, and was ascribed to selective disruption of the fibers projecting from the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF) to the oculomotor nuclear complex. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare cause of ophthalmoplegia and crossed vertical gaze palsy has not been described in this disorder. Our patient with a circumscribed acute infarction involving the left mesodiencephalic junction due to CADASIL showed both upward and downward gaze palsy in both eyes, but more marked depression paresis in the ipsilesional eye and more conspicuous elevation deficit in the contralesional eye, which was consistent with crossed vertical gaze palsy. We provide alternate explanation for this rare phenotype of vertical gaze palsy. Selective disruption of riMLF fibers may cause crossed vertical gaze palsy in unilateral mesodiencephalic lesion.

Bilateral, vertical supranuclear gaze palsy following unilateral midbrain infarct

A 60-year-old man recently admitted for bipedal oedema, endocarditis and a persistently positive COVID-19 swab with a history of anticoagulation on rivaroxaban for atrial fibrillation, transitional cell carcinoma, cerebral amyloid angiopathy, diabetes and hypertension presented with sudden onset diplopia and vertical gaze palsy. Vestibulo-ocular reflex was preserved. Simultaneously, he developed a scotoma and sudden visual loss, and was found to have a right branch retinal artery occlusion. MRI head demonstrated a unilateral midbrain infarct. This case demonstrates a rare unilateral cause of bilateral supranuclear palsy which spares the posterior commisure. The case also raises a question about the contribution of COVID-19 to the procoagulant status of the patient which already includes atrial fibrillation and endocarditis, and presents a complex treatment dilemma regarding anticoagulation.

Bilateral vertical gaze palsy due to midbrain infarct associated with iron deficiency anemia in a young boy

An 8-year-old boy presented with complaints of sudden-onset binocular vertical diplopia of one day duration. Ophthalmic examination showed restricted up- and downgaze movement with rotatory nystagmus. Systemic investigations revealed iron-deficiency anemia and localized acute infarct in the left paramedian rostral and dorsal part of the upper midbrain at the level of the red nucleus on magnetic resonance imaging. The patient was started on oral iron supplement, which resulted in symptomatic as well as clinical improvement after 2 weeks.

Vertical Gaze Palsy Caused by Selective Unilateral Rostral Midbrain Infarction

Vertical gaze palsy is rarely a neurological symptom, although it has been observed in some cases. Here, we report the case of a patient presenting with complete upward and downward gaze palsy. In this case, a small lesion in the left rostral midbrain was observed on diffusion-weighted magnetic resonance (MR) images, and the lesion was considered to cause the ocular symptom. We consider that vertical gaze palsy is an important clue to an accurate topical diagnosis of a brain lesion.

The CAM test: a novel tool to quantify the decline in vertical upper limb pointing movements with ageing

BACKGROUND AND AIM

Although upper limb movements in the vertical plane are very commonly used during the activities of daily life, there is still a lack of a reliable and easy standardized procedure to quantify them. In particular, ageing is associated with a decline in performances of coordinated movements, but a tool to quantify this decline is missing.

METHODS

We created a novel portable test called counting arm movement test (CAM test). Participants were asked to perform fast and accurate successive pointing movements towards two fixed targets (mechanical counters) located in a vertical plane in the parasagittal axis during three different time periods (15, 30, 45 s). Each upper limb was assessed separately. The test was evaluated in a group of 63 healthy subjects (mean age ± SD 49.1 ± 19.8 years; F/M 33/30; range 18-87 years).

RESULTS

Motor performances (number of clicks) significantly decreased as a function of age for both the dominant side (age effect; linear regression; p < 0.0001 for 15, 30 and 45 s) and the non-dominant side (linear regression; p < 0.0001 for 15, 30 and 45 s). Performances on the dominant and non-dominant side were linearly correlated with the time periods (p < 0.0001 on both sides). The symmetry index (ratio of performance on the dominant side divided by performance on the non-dominant side) was correlated linearly and positively with the duration of the test (y = 0.002x + 1.053; p = 0.0056). We also found a linear relationship between upper limb length and motor performance on the non-dominant side for 15 s (p = 0.023) and 45 s (p = 0.041). The test was characterized by a very high correlation between the results obtained by two investigators during two successive sessions in a subgroup of 7 subjects (Pearson product moment correlation: 0.989 for the dominant side and 0.988 for the non-dominant side).

CONCLUSION

The CAM test appears as a robust and low cost tool to quantify upper limb pointing movements. In particular, the test strongly discriminates the effects of age upon motor performances in upper limbs. Future studies are now required to establish the sensitivity, specificity and reliability of this procedure in selected neuromuscular or skeletal diseases affecting the elderly.

Detection of third and sixth cranial nerve palsies with a novel method for eye tracking while watching a short film clip

OBJECT

Automated eye movement tracking may provide clues to nervous system function at many levels. Spatial calibration of the eye tracking device requires the subject to have relatively intact ocular motility that implies function of cranial nerves (CNs) III (oculomotor), IV (trochlear), and VI (abducent) and their associated nuclei, along with the multiple regions of the brain imparting cognition and volition. The authors have developed a technique for eye tracking that uses temporal rather than spatial calibration, enabling detection of impaired ability to move the pupil relative to normal (neurologically healthy) control volunteers. This work was performed to demonstrate that this technique may detect CN palsies related to brain compression and to provide insight into how the technique may be of value for evaluating neuropathological conditions associated with CN palsy, such as hydrocephalus or acute mass effect.

METHODS

The authors recorded subjects' eye movements by using an Eyelink 1000 eye tracker sampling at 500 Hz over 200 seconds while the subject viewed a music video playing inside an aperture on a computer monitor. The aperture moved in a rectangular pattern over a fixed time period. This technique was used to assess ocular motility in 157 neurologically healthy control subjects and 12 patients with either clinical CN III or VI palsy confirmed by neuro-ophthalmological examination, or surgically treatable pathological conditions potentially impacting these nerves. The authors compared the ratio of vertical to horizontal eye movement (height/width defined as aspect ratio) in normal and test subjects.

RESULTS

In 157 normal controls, the aspect ratio (height/width) for the left eye had a mean value ± SD of 1.0117 ± 0.0706. For the right eye, the aspect ratio had a mean of 1.0077 ± 0.0679 in these 157 subjects. There was no difference between sexes or ages. A patient with known CN VI palsy had a significantly increased aspect ratio (1.39), whereas 2 patients with known CN III palsy had significantly decreased ratios of 0.19 and 0.06, respectively. Three patients with surgically treatable pathological conditions impacting CN VI, such as infratentorial mass effect or hydrocephalus, had significantly increased ratios (1.84, 1.44, and 1.34, respectively) relative to normal controls, and 6 patients with supratentorial mass effect had significantly decreased ratios (0.27, 0.53, 0.62, 0.45, 0.49, and 0.41, respectively). These alterations in eye tracking all reverted to normal ranges after surgical treatment of underlying pathological conditions in these 9 neurosurgical cases.

CONCLUSIONS

This proof of concept series of cases suggests that the use of eye tracking to detect CN palsy while the patient watches television or its equivalent represents a new capacity for this technology. It may provide a new tool for the assessment of multiple CNS functions that can potentially be useful in the assessment of awake patients with elevated intracranial pressure from hydrocephalus or trauma.

Profile of Gaze Dysfunction following Cerebrovascular Accident

Aim. To evaluate the profile of ocular gaze abnormalities occurring following stroke. Methods. Prospective multicentre cohort trial. Standardised referral and investigation protocol including assessment of visual acuity, ocular alignment and motility, visual field, and visual perception. Results. 915 patients recruited: mean age 69.18 years (SD 14.19). 498 patients (54%) were diagnosed with ocular motility abnormalities. 207 patients had gaze abnormalities including impaired gaze holding (46), complete gaze palsy (23), horizontal gaze palsy (16), vertical gaze palsy (17), Parinaud's syndrome (8), INO (20), one and half syndrome (3), saccadic palsy (28), and smooth pursuit palsy (46). These were isolated impairments in 50% of cases and in association with other ocular abnormalities in 50% including impaired convergence, nystagmus, and lid or pupil abnormalities. Areas of brain stroke were frequently the cerebellum, brainstem, and diencephalic areas. Strokes causing gaze dysfunction also involved cortical areas including occipital, parietal, and temporal lobes. Symptoms of diplopia and blurred vision were present in 35%. 37 patients were discharged, 29 referred, and 141 offered review appointments. 107 reviewed patients showed full recovery (4%), partial improvement (66%), and static gaze dysfunction (30%). Conclusions. Gaze dysfunction is common following stroke. Approximately one-third of patients complain of visual symptoms, two thirds show some improvement in ocular motility.

Unilateral asterixis, thalamic astasia and vertical one and half syndrome in a unilateral posterior thalamo-subthalamic paramedian infarct: An interesting case report

A 42-year-old young lady presented with acute onset of dizziness, drooping of left eye with binocular diplopia and inability to walk unassisted. She had past history of uncontrolled diabetes mellitus and hypertension. On examination, she had left fascicular type of third nerve palsy, vertical one and half syndrome (VOHS), left internuclear ophthalmoplegia and skew deviation with ipsilesional hypertropia. She also had thalamic astasia and right unilateral asterixis. Her MRI revealed T2 and Flair hyper intense signal changes with restricted diffusion in the left thalamus, subthalamus and left midbrain. MR Angiography was normal. Thalamic-subthalamic paramedian territory infarct is relatively uncommon. It can present with oculomotor abnormalities including vertical one and half syndrome, skew deviation, thalamic astasia and asterixis. This case is reported for the rarity of the presenting clinical findings in unilateral thalamo-mesencephalic infarcts.

The subcommissural organ and the development of the posterior commissure

Growing axons navigate through the developing brain by means of axon guidance molecules. Intermediate targets producing such signal molecules are used as guideposts to find distal targets. Glial, and sometimes neuronal, midline structures represent intermediate targets when axons cross the midline to reach the contralateral hemisphere. The subcommissural organ (SCO), a specialized neuroepithelium located at the dorsal midline underneath the posterior commissure, releases SCO-spondin, a large glycoprotein belonging to the thrombospondin superfamily that shares molecular domains with axonal pathfinding molecules. Several evidences suggest that the SCO could be involved in the development of the PC. First, both structures display a close spatiotemporal relationship. Second, certain mutants lacking an SCO present an abnormal PC. Third, some axonal guidance molecules are expressed by SCO cells. Finally, SCO cells, the Reissner's fiber (the aggregated form of SCO-spondin), or synthetic peptides from SCO-spondin affect the neurite outgrowth or neuronal aggregation in vitro.

Vertical ophthalmoplegia due to a unilateral periaqueductal gray matter infarct in an adolescent

Brainstem strokes affecting the periaqueductal gray matter of the midbrain can cause vertical ophthalmoplegia. Accompanying clinical features are frequently associated and reflect the involvement of other brainstem structures. We report on an adolescent presenting with vertical gaze palsy and left mydriatic pupil as the only clinical expression of a small infarct located in the left periaqueductal gray matter. Even when the lesion was strictly unilateral, vertical ophthalmoplegia affected both eyes.

[Progressive supranucleair palsy: acetylcholineeserase-inhibitor a possible therapy?]

Progressive supranucleair palsy (PSP) is a serious neurologic disease which is seldom diagnosed due to its complexity. In 1996 international diagnostic criteria were developed by a group of experts, the diagnosis remains complicated. We describe three cases, which were followed in the period 2001-2008. In these case reports we elaborate on the therapeutic use of rivastigmine. During off-label rivastigmine use, patients showed minimal further cognitive decline, specifically with respect to frontal defects. However, larger studies and trials are necessary to explore the effects of rivastigmine in patients with PSP.

Ocular motor syndromes of the brainstem and cerebellum

PURPOSE OF REVIEW

The brainstem and cerebellum contain many neuronal types that play a critical role in eye movement control. In a physiological approach, understanding how these neuronal assemblies cooperate provides strong insight into general brain functions. Furthermore, eye movements provide an interesting model for understanding neural mechanisms of sensorimotor learning, and a knowledge of the mechanisms underlying oculomotor plasticity is essential for correctly diagnosing and effectively managing patients. Finally, knowledge of the ocular motor syndromes frequently helps localize the pathological abnormality.

RECENT FINDINGS

We review the recently published works dealing with the physiological organization and pathology of slow and rapid eye movements at a brainstem and cerebellar level.

SUMMARY

The main recent findings of great interest for clinical practice or research concern the physiopathology of head shaking nystagmus, downbeat nystagmus and oculopalatal tremor; the neural substrates of three-dimensional control of eye movements and of optokinetic nystagmus; the understanding of saccade generation and of its consequences on physiological and pathological eye oscillations; and, finally, the physiological basis of saccadic adaptation.

Disorders of saccades

Saccades are rapid eye movements that assist vision by pointing the fovea of the retina, which contains the highest density of photoreceptors, at features of interest in the visual environment. A great deal is now known about the properties and neurobiology of saccades in both health and disease states. They have consequently become a valuable diagnostic and research tool. In this review, we describe the common saccadic disorders and their causes. We also highlight recent insights into the pathophysiologic mechanisms underlying these disorders and discuss how these insights have helped increase our understanding of the saccadic system as a whole.