Ocular lateral deviation as a vestibular clinical sign of medial posterior inferior cerebellar artery strokes: A case report

We report a case of posterior circulation stroke that presented with a unique ocular vestibular sign called Ocular Lateral Deviation (OLD). OLD is eye deviation to one side that is made more prominent by brief eye closure. OLD has been reported to occur ipsilesional in a third of medullary strokes, and occasionally in other posterior fossa strokes. Here we report a case of acute stroke that presented with contralesional eye deviation consistent with OLD due to inferior vermis stroke. To our knowledge, this presentation has not been reported before. Clinicians should be aware of potential ocular manifestations of posterior circulation strokes, as these syndromes may not generate significant NIHSS scores and may be missed.

Subtle ocular movements in a patient with brain death

Introduction and Case Presentation: Brain death can be associated with limb movements that are attributed to spinal reflexes. Although head/face movements have been rarely reported, no case of overt eye movements in brain death has been documented. We report a case of a patient with subtle eye movements whose exam was otherwise consistent with brain death. The presence of eye movements delayed pronouncing the patient as brain dead and delayed organ donation. We agree with American Academy of Neurology Position statement from 2019 that brain death does not mean demise of every neuron. Discussion: This case raises important questions about the types of movements that should be "allowed" during the determination of brain death to avoid delays in diagnosis.

Demonstration of post-growth wavelength setting of VCSELs using high-contrast gratings

We demonstrate, for the first time, post-growth wavelength setting of electrically-injected vertical-cavity surface-emitting lasers (VCSELs) by using high-contrast gratings (HCGs) with different grating parameters. By fabricating HCGs with different duty cycle and period, the HCG reflection phase can be varied, in effect giving different optical cavity lengths for HCG-VCSELs with different grating parameters. This enables fabrication of monolithic multi-wavelength HCG-VCSEL arrays for wavelength-division multiplexing (WDM). The GaAs HCG is suspended in air by removing a sacrificial layer of InGaP. Electrically-injected 980-nm HCG-VCSELs with sub-mA threshold currents indicate high reflectivity from the GaAs HCGs. Lasing over a wavelength span of 15 nm was achieved, enabling a 4-channel WDM array with 5 nm channel spacing. A large wavelength setting span was enabled by an air-coupled cavity design and the use of only the HCG as top mirror.

Rapidly progressive fatal bihemispheric infarction secondary to Moyamoya syndrome in association with Graves thyrotoxicosis

Moyamoya syndrome is the secondary form of intracranial arterial occlusive diseases that produces collateral vessels from the base of brain. We report a case of Moyamoya syndrome developing in association with Graves thyrotoxicosis; as a result of its rapid progression and severe global ischemia, it was ultimately fatal. Because of the rarity of this association, we reviewed the literature in an attempt to establish possible demographic and clinical characteristics that may suggest putative mechanisms of pathogenesis.

Steroid-responsive charles bonnet syndrome in temporal arteritis

The authors report a patient with biopsy-proven temporal arteritis who manifested Charles Bonnet syndrome (CBS). Treatment with steroid resulted in prompt resolution of visual hallucinations, despite persistent visual loss, suggesting that cerebral ischemia is a cofactor for the development of CBS.

Quantum teleportation with a quantum dot single photon source

We report the experimental demonstration of a quantum teleportation protocol with a semiconductor single photon source. Two qubits, a target and an ancilla, each defined by a single photon occupying two optical modes (dual-rail qubit), were generated independently by the single photon source. Upon measurement of two modes from different qubits and postselection, the state of the two remaining modes was found to reproduce the state of the target qubit. In particular, the coherence between the target qubit modes was transferred to the output modes to a large extent. The observed fidelity is 80%, in agreement with the residual distinguishability between consecutive photons from the source. An improved version of this teleportation scheme using more ancillas is the building block of the recent Knill, Laflamme, and Milburn proposal for efficient linear optics quantum computation.

Hemiplegic migraine induced by exertion

BACKGROUND

It is known that exertion can aggravate migraine headache. However, the relationship between exertion and migraine aura is unknown.

OBJECTIVE

To study the relationship between exertion and migraine aura.

DESIGN

Case report.

SETTING

Tertiary care hospital.

PATIENT

A 67-year-old man presented with recurrent attacks of exertion-induced hemiplegic migraine. Since the hemiparetic attacks were exertion induced, they were initially ascribed to recurrent transient ischemic attacks. However, the clinical picture, normal findings on cerebral angiography and neuroimaging (during the period of hemiparesis), lack of response to treatment with antiplatelets and anticoagulants, and successful treatment with verapamil suggested that the hemiparesis was not due to ischemia, but was indeed a migraine aura. We suggest that exertion induced the aura of hemiparesis by lowering the threshold for the development of cortical spreading depression. Even though our patient had no family history of hemiplegic migraine, a mutation in an ion channel gene (eg, the CACNA1A gene on chromosome 19) might account for his episodic attacks.

CONCLUSION

Migraine aura should be included in the differential diagnosis of exertion-induced focal neurologic deficit.