Prelim- Chapter 1 Flashcards
Seeks and hold a visual image
Skeletal (convergence)
Discriminates and defines the image
Visceral ( accommodation)
Unifies, elaborates and unifies the image
Cortical (perceptual)
The only image existing in the brain is_______ which are ever in motion, fluctuating in amount and intensity
electrochemical fields
3 questions from patient
- What is my visual problem?
- What have I done to meet this problem?
- What can be done to eliminate this problem?
To answer the three questions, the optometrist must perform:
- Case study to determine the cause of the problem
- A visual skills profile to determine what the patients did to meet this problem
- Corrective procedures to eliminate the problem
- A progress report to determine the amount of visual improvement obtained by the patient and to ascertain if the problem has been eliminated
Record far point and near point, determine the kind, type and extent of the visual problem
Binocular case analysis
Purpose of case analysis
- To find the limitations of the prescriptible lens for distance and for near
- To determine whether the case can be handled by lens application alone
- To follow the changes in relationship between accommodation and convergence brought about by the new rx or the vision training program or both (progress report examination)
That which agrees with the regular and established type.
Conformance to the natural order of things.
Normal eye
Different approaches to the problem of clarifying objects or things whether they are normal or abnormal
Normative or physical viewpoint
Pathological viewpoint
Statistical viewpoint
Requires that the system must posses certain ideal values in order to be considered normal
Normative or physical viewpoint
A normal system is one which is free of pathology, a system which has no abnormal disturbances. We do not consider the degenerative processes associated with aging as being of a pathological nature.
Pathological viewpoint
is one in which the optical system needs no auxiliary lenses to obtain a sharp focus at the retinal plane. It establishes an arbitrary value of emmetropia and orthophoria as the normal conditions for efficient vision.
The normative or physical normal eye
is used to inhibit accommodation to its fullest extent, optometrists all realize that this mechanism will change because some residual accommodation is active. We never examine the visual mechanism as if it were a fixed system.
Fogging method
___________ and __________ instead of being ideal conditions for the visual mechanism, are in reality abnormal conditions which are prevalent in those individuals classifed as retarded readers. In fact, emmetropia and orthophoria, when found in an individual, seem to indicate the presence of a visual problem.
emmetropia and orthophoria,
An eye so constructed that parallel rays of light come to a focus in the retina without any effort of accommodation
Emmetropia
It is the condition of a normal eye in which the retina is situated at the posterior principal focus distance of the refracting system so that when accommodation at rest parallel rats of light is brought to focus at the retina
Emmetropia
The condition in which, the motor muscles being at rest, the visual axes are parallel to each other. This state of normal balance obtains not only when the eyes are in ordinary use, but also when they are subjected to a balance test
Orthophoria
“The ideal state of binocular balance; there exists no manifest deviation under dissociation.
Orthophoria
“When the passive position of functional rest is also the primary position; such a perfectly balanced condition of the oculo-motor system is described as orthophoria.”
Orthophoria