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Chordoid glioma of the third ventricle (CGTV) is a rare, slow-growing, World Health Organization Grade II glial tumor, with stereotyped localization in the anterior third ventricle. Despite being considered a noninvasive tumor, CGTV is usually associated with a poor clinical outcome due to its close proximity to important cerebral structures, such as the hypothalamus and visual pathways. Our patient with CGTV experienced visual involvement, but after subtotal surgical resection showed no evidence of progression at 5-year follow-up.

BACKGROUND Cortical remapping after peripheral or central visual deafferentation alters visual perception, but it is unclear whether such a phenomenon impinges on areas remote from a scotoma. To investigate this question, we studied variations of perceptual spatial distortion in the visual field of patients with homonymous paracentral scotoma. METHODS Two patients with right inferior homonymous paracentral scotoma were asked to describe their perception of a series of figures showing two isometric vertical lines symmetrically located on either side of a fixation point. In each figure, the fixation point varied by steps of 2 degrees along a hypothetical vertical line equidistant between the test lines. The lines subtended 20 degrees of visual angle, and the right line passed through the scotoma in both cases. Time for spatial distortion to manifest was recorded. RESULTS Both subjects reported that the right line was perceived as shorter than the left one. The line shortening varied in magnitude with the distance of the fixation point from the end of the line and was more pronounced when the distance increased. Moreover, perceptual line shortening appeared 5-10 seconds after steady fixation, but values of shortening varied during the following 10 seconds. In addition, the right line appeared uninterrupted or slightly blurred in the scotoma region. CONCLUSIONS These observations reflect long-range cortical reorganization after brain damage. Larger receptive fields in the periphery of the visual map could explain why perceptual shortening is more pronounced with increased eccentricity.

It was long held that, following alterations in sensory input, structural changes in the primary visual cortex take place only in early life, during so-called "critical periods." Recently, however, it has been established that, in adults, cortical maps in the brain are not fixed, and the cortex does not perform stereotyped operations. Instead, neuronal receptive fields in the cortex can reorganize following deactivation or an altered pattern of activation. Plasticity is essential for the normal adjustment of the brain to modifications in the sensory environment, and for improving perceptual skills and sensorimotor performances. It also plays a crucial role in recovery from damage to the visual system. Cortical remapping generates a filling-in of visual field defects. Consequently, it alters the image perceived. Cortical rearrangement following lesions in the visual pathways does not restore function to the destroyed tissue, but it helps to compensate for gaps in perception. In this review article, we focus on effects of plasticity in the adult visual cortex which are of major importance in the daily practice of neuroophthalmology. Cortical reorganization, together with resulting filling-in, affects the early recognition and evaluation of visual field defects. The importance of brain remapping in these matters is still largely underestimated by clinicians.

We examined a 30-year-old woman who, for 6 months, had suffered from ocular neuromyotonia, which consisted of episodic ocular depression. Apart from the ocular complaint, her medical history and the clinical findings were unremarkable. The patient discovered that she could terminate each episode of tonic ocular depression instantly by forcefully directing her gaze upward. Stretching the affected muscle might also prove to be an effective way of ending attacks of neuromyotonia in other patients suffering from this condition.

The treatment of optic nerve sheath meningiomas (ONSM) is controversial. Radiation therapy has been used with some success in patients with progressive visual loss. We report a case of visual improvement in a patient with an optic nerve sheath meningioma and progressive visual field loss, treated with conformal radiotherapy.

We treated five patients with vestibular neuritis who had strabismus. Three of them spontaneously noted vertical diplopia. During the following weeks and months, strabismus progressively resolved, indicating the recently acquired nature of the oculomotor condition. In three of these individuals, a change in visual vertical and cyclo-torsion of the globes suggested that strabismus was a form of skew deviation that occurred as a part of an ocular tilt reaction resulting from the peripheral vestibular lesion. Strabismus appears to occur frequently in this common vestibular condition.