Seminars in Ophthalmology, 21:213, 2006 Copyright c Informa Healthcare>> Health care ISSN: 0882-0538 DOI: 10.1080/08820530601120881 Introduction Walter M. Jay Department of Ophthalmology, Loyola University Medical>> medicine Center, Maywood, IL, USA This issue of Seminars in Ophthalmology contains a collection of articles devoted to the field of Neuro-Ophthalmology. The first article by Kardon, Morrisey, and Lee entitled “Abnormal multifocal>> Progressive lens electroretinogram (MERG) in ethambutol>> Ethambutol toxicity>> Toxicity” uses a relatively new electrophysiologic>> Electrophysiology technique to shed light on a disease>> Disease entity that was previously thought to be purely an optic nerve>> Optic nerve disease>> Disease. Conventional electroretinography records a diffuse or global retinal>> Retinal response. In multifocal>> Progressive lens electroretinography, measurements are taken in focal areas of the retina>> Retina in a perimetric fashion. Thus, localized retinal>> Retinal abnormalities may be determined. Ethambutol toxicity>> Toxicity has long been considered a disorder of the optic nerve>> Optic nerve. The present article concludes that based upon abnormal MERG findings, ethambutol>> Ethambutol toxicity>> Toxicity affects not only the optic nerve>> Optic nerve, but probably other retinal elements>> Photoreceptor cell as well. The Guillain-Barre Syndrome>> Guillain–Barré syndrome (GBS) is characterized by an ascending muscle>> Muscle paralysis>> Paralysis with progressive loss of muscle>> Muscle stretch reflexes. The syndrome>> Syndrome is of importance to ophthalmologists>> Ophthalmology in that the Fisher variant of GBS may present with ophthalmoplegia>> Ophthalmoparesis. In “GQIb antibody>> Antibody testing in Guillain-Barre syndrome>> Guillain–Barré syndrome and variants,” Chaudrhy et al. reviews the clinical features of GBS and various subtypes. The article also discusses the value of using a specific blood test>> Blood test, GQ1b antibody>> Antibody testing, in diagnosing the disease>> Disease. By studying a patient with a rare disease>> Rare disease with oculomotor>> Oculomotor nerve recordings, it is sometimes possible to obtain a deeper understanding of the underlying oculomotor>> Oculomotor nerve mechanisms. In “‘Staircase’ saccadic>> Saccade intrusions plus transient yoking and neural>> Nervous system integrator failure associated with cerebellar hypoplasia>> Cerebellar hypoplasia: a model stimulator,” Rucker et al. studied a patient with Joubert syndrome, a disease>> Disease characterized by severe hypotonia>> Hypotonia, ataxic>> Ataxia speech, motor and language delays, and torticollis>> Torticollis. In the present articles, the authors present hypothesized ocular motor mechanisms of unique “staircase-like” sequences of saccadic>> Saccade intrusions in one direction which they have named “staircase saccadic>> Saccade intrusions.” Internuclear ophthalmoplegia (INO) is commonly associated with multiple sclerosis>> Multiple sclerosis and midbrain strokes>> Stroke. It may also rarely be seen following trauma. Doe and Jay describe a case of a 23 year old man who developed a unilateral traumatic internuclear ophthalmoplegia>> Internuclear ophthalmoplegia following a fall from a roof. MRI>> Magnetic resonance imaging revealed a midbrain lesion>> Lesion slightly left of midline. The article also reviews previous cases of traumatic internuclear ophthalmoplegias found in the medical>> medicine literature. Finally, Bajwa et al. reviews the neuro-ophthalmologic>> ophthalmology manifestations of epilepsy>> Epilepsy. The article emphasizes that there is considerable overlap in the transient visual>> Visual system disturbances in epilepsy>> Epilepsy and those found in migraines and transient ischemic attacks>> Transient ischemic attack. As guest editor of this issue of Seminars in Ophthalmology, I do hope that you find this issue both enlightening and enjoyable. 213