BACKGROUND Neuromyelitis optica (NMO) is an inflammatory demyelinating disease that predominantly affects the optic nerves and the spinal cord, and is possibly mediated by an immune mechanism distinct from that of multiple sclerosis (MS). Central scotoma is recognized as a characteristic visual field defect pattern of optic neuritis (ON), however, the differing pathogenic mechanisms of NMO and ...

Patients with central scotoma use a preferred retinal locus (PRL) of fixation to perform visual tasks. Some of the conditions that cause central scotoma are progressive, and as a consequence, the PRL needs to be adjusted throughout the progression. The present study investigates the peripheral locus of fixation in subjects under a simulation of progressive central scotoma. Five normally sighted...

purpose : visual loss associated with multiple traumas in the context of road traffic accident, especially when the maxillofacial and orbital areas are not directly injured, is an uncommon occurrence. the possibility of purtscher’s retinopathy, i.e. retinal manifestation of mechanical trauma elsewhere in the body, as the cause of visual disturbance in these situations can often be overlooked. p...

The objective of this study is to investigate the characteristics and the evolution of visual field damage caused by Leber's hereditary optic neuropathy (LHON) and to provide clinical data for the diagnosis of LHON. Parameters of visual field in 32 consecutive patients (49 eyes) with LHON who were confirmed by genetic diagnostic tests were retrospectively measured within 1 week, between three t...

Amsler's charts have long proved to be very useful for detecting organic macular and paramacular disorders. The chart consists of a grid of lines with a central fixation dot, the whole chart at 30 cm. distance subtending an angle of 200 (Amsler, I949). In the examination of functional amblyopia, we have found that the use of an Amsler chart can be very helpful in understanding the difference be...

Patients with a central scotoma usually use a preferred retinal locus (PRL) consistently in daily activities. The selection process and time course of the PRL development are not well understood. We used a gaze-contingent display to simulate an isotropic central scotoma in normal subjects while they were practicing a difficult visual search task. As compared to foveal search, initial exposure t...

Reading rates are slower for persons with low vision than for normally-sighted persons. This study investigated the change in reading performance and reading eye movements when we simulated the two most common causes of low vision--central field loss and cataract--and their combination (scotoma + cataract). Three subjects read sentences with each of these simulated impairments at five different...

A visual field study of 50 cases of unilateral functional amblyopia revealed a relative central scotoma of 2-10 degrees width and 0.1 to 0.8 LU (log units of neutral density filters) depth in 29 out of 50 cases by static perimetry, while kinetic perimetry revealed a central scotoma in only 3 cases of paramacular fixation. In the majority of cases the eccentric area of fixation lay on the edge o...