What is Seidel scotoma?
Seidel’s sign (also called Seidel’s scotoma) is a sickle-shaped scotoma that is a superior or inferior extension of the blind spot. It occurs in some patients with glaucoma.
What is bjerrum screen?
Bjerrum screen – a flat, usually black surface used to measure the central 30 degrees of the field of vision.
What is Cecocentral scotoma?
Cecocentral scotomas: These are visual field defects that extend from the central vision to the natural blind spot. This type of field defect usually represents an insult to the cluster of retinal ganglion cells called the papillomacular bundle.
What is foveal scotoma?
As the region of the foveal blue scotoma is defined by differences in relative sensitivity to light rather than blindness, it is more related to local bleaching of photo-pigments and/or neural adaptation than to scotomata caused by lesions of the retina or central visual pathways, or to the blind spot.
What is refractive scotoma?
A scotoma is an area of partial alteration in the field of vision consisting of a partially diminished or entirely degenerated visual acuity that is surrounded by a field of normal – or relatively well-preserved – vision. Every normal mammalian eye has a scotoma in its field of vision, usually termed its blind spot.
What is absolute scotoma?
absolute scotoma an area within the visual field in which perception of light is entirely lost. annular scotoma a circular area of depressed vision surrounding the point of fixation.
What does Dyschromatopsia mean?
Definition. A form of colorblindness in which only two of the three fundamental colors can be distinguished due to a lack of one of the retinal cone pigments. [ from HPO]
What causes Cecocentral scotoma?
Conclusions: In spite of a selective referral bias, retinal disease was the most common pathophysiology causing central and cecocentral scotomas. The addition of OCT and anatomic studies helped to distinguish these, although even when the macula looked normal, functional studies such as multifocal ERG may be necessary.
What do scotomas look like?
Scotomas are a type of aura, a visual phenomenon, that’s fairly common. Scintillating scotomas may look wavy or alternate growing from dark to light again. The edges of the spot you see are often jagged. Headache pain may occur along with scintillating scotomas, or you may feel no pain at all.
Which is the best description of a Bjerrum scotoma?
Bjerrum scotoma – a comet-shaped scotoma, occurring in glaucoma. Synonym (s): Bjerrum sign; sickle scotoma Bjerrum screen – a flat, usually black surface used to measure the central 30 degrees of the field of vision. Synonym (s): tangent screen
Is there a comet-shaped scotoma in glaucoma?
a comet-shaped scotoma, occurring in glaucoma, attached at the temporal end to the blind spot or separated from it by a narrow gap; the defect widens as it extends above and nasally curves around the fixation spot, and then extends downward to end exactly at the nasal horizontal meridian.
Why was Bjerrum interested in the visual field?
At that time Bjerrum was studying the visual field by means of small white objects. The idea of this investigation was to record the performance of every single functional unit of the retina. As a minimum such units in Bjerrum’s opinion would subtend a visual angle of one minute of arc (in the macular region).