Publications by authors named "Nathan H Kung"

A 21-year-old man experienced unilateral vision loss associated with multiple atrophic chorioretinal lesions. He was treated for a presumptive diagnosis of acute retinal necrosis, but his vision did not improve with antiviral therapy. Over the course of several weeks, his symptoms progressed to involve both eyes.

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Skew deviation is a rare side effect of intratympanic gentamicin injection for intractable Meniere's disease. When the skew deviation is accompanied by pathologic head tilt and ocular torsion, the result is an ocular tilt reaction (OTR). The authors report the case of a 56-year-old man with refractory Meniere's disease who developed binocular vertical diplopia following intratympanic gentamicin injection and was found to have skew deviation and a partial ocular tilt reaction.

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The acute vestibular syndrome (AVS) is characterized by the rapid onset of vertigo, nausea/vomiting, nystagmus, unsteady gait, and head motion intolerance lasting more than 24 hours. We present 4 patients with AVS to illustrate the pearls and pitfalls of the Head Impulse, Nystagmus, Test of Skew (HINTS) examination.

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Importance: Diagnostic error is an important source of medical error. Overdiagnosis of optic neuritis may prompt unnecessary and costly diagnostic tests, procedures, and treatments.

Objective: To assess the incidence of and characterize factors contributing to overdiagnosis of acute optic neuritis.

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A 50-year old man presented for evaluation of progressive gait ataxia with a superimposed spastic paraparesis. During his clinic visit, he was also observed to have slow and limited eye movements. In this article, we discuss the clinical approach to this triad of symptoms and guide the reader to discover the patient's ultimate genetic diagnosis.

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Vertebrobasilar dolichoectasia (VBD) is characterized by significant dilation, elongation, and tortuosity of the vertebrobasilar system. We present a unique case of VBD, confirmed by neuroimaging studies, showing vascular compression of the right optic tract and lower cranial nerves leading to an incongruous left homonymous inferior quadrantanopia and glossopharyngeal neuralgia.

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A 37-year-old man with a history of progressive bilateral sensorineural hearing loss presented to a neuro-ophthalmology clinic with an acute left homonymous hemianopsia. In this article, we discuss the clinical approach and differential diagnosis of progressive combined vision and hearing loss and guide the reader to discover the patient's ultimate diagnosis.

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A 29-year-old woman presented with blurred vision and distal paresthesias. Her initial evaluation revealed severe bilateral optic disc edema with distal lower-extremity sensory and motor deficits and electrodiagnostic evidence of a length-dependent mixed demyelinating and axonal polyneuropathy. The results of routine diagnostic testing, including laboratory tests, magnetic resonance imaging, and lumbar puncture, were nondiagnostic.

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An isolated ocular motor nerve palsy is defined as dysfunction of a single ocular motor nerve (oculomotor, trochlear, or abducens) with no associated or localizing neurologic signs or symptoms. When occurring in patients aged 50 or older, the most common cause is microvascular ischemia, but serious etiologies such as aneurysm, malignancy, and giant cell arteritis should always be considered. In this article, the authors review the clinical approach, anatomy, and differential diagnosis of each isolated ocular motor nerve palsy and discuss the clinical characteristics, pathophysiology, and treatment of microvascular ischemia.

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Ocular neuromyotonia (ONM) is a neuro-ophthalmic disorder characterized by episodic diplopia caused by contraction of one or more ocular muscles due to spontaneous excitation of the respective ocular motor nerve. We report a patient whose ocular neuromyotonia arose in the setting of a subacute demyelinating polyneuropathy consistent with chronic inflammatory demyelinating polyneuropathy (CIDP) and subsequently resolved following the initiation of intravenous immunoglobulin (IVIg) for her neuropathy. Our patient provides additional evidence towards the role of demyelination and ephaptic neurotransmission in ocular neuromyotonia and also represents the first reported case of ocular neuromyotonia associated with a systemic neurological condition.

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