VISUAL THERAPY IN CHILDREN WITH SPECIAL NEEDS
Núria Risco Subirà. Optometrist
LENSES AND PRISMS
A significant proportion of children with cerebral palsy experience refractive errors, such as high hyperopia, myopia, and astigmatism. Nevertheless, fitting glasses for these individuals requires careful consideration, recognizing that many may not attain optimal vision due to the consequences of their cerebral lesion.
In the realm of vision therapy, our objective extends beyond correcting refractive errors. We seek to harness the potential of lenses not only to address these errors but also to enhance the child's visual efficiency. Sometimes, subtle adjustments in prescription or the incorporation of prisms can yield meaningful changes in attention, focus, and posture. By tailoring interventions to each child's specific visual needs, we aim to optimize their visual capabilities and contribute to overall improvements in their visual function.
DIFFERENT TYPES OF LENSES AND PRISM
CORRECTIVE LENSES
The optical correction recommended by optometry aims to achieve maximum visual acuity, comfort, and efficiency, considering all parameters identified during the visual efficacy examination.
The purpose of the lens is not only to compensate for the visual defect but also to optimize performance, ensuring that individuals feel more secure and experience relaxed vision.
YOUTH PRISMS
An optical prism is a lens that, when looked through, causes an apparent displacement of a fixed object.
Prisms can have a compensatory purpose or aim to enhance visual performance.
The primary goal is to alter the perception of space, inducing individuals to adjust their visual and body posture and make changes in their overall behavior.
POSTURAL PRISMS
A low-power prismatic lens induces a tonic adjustment of muscle fibers, specifically promoting relaxation to reposition the image in a comfortable fusion position.
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More precisely, they induce the relaxation of the inferior oblique muscle, and since this muscle is linked to skeletal muscles through the proprioceptive system, those muscles also relax. Consequently, prisms alter the input of proprioceptive information.v
Yoked prisms versus Postural prisms
Yoked prisms
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To treat binocular vision problems: insufficient and excessive convergence and divergence, accommodative problems: insufficient and excessive accommodation, recent myopia.
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Highly recommended in cases of brain injury and traumatic brain injury: helping to modify the posture of the head, body and gait.
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In cases of nystagmus to direct the sight towards blocking positions.
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In homonymous hemianopsias by moving the object from not seen to where it is seen.
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In patients who have gaze restriction, because they are bedridden, or for those who have physical mobility limitations, or even for those affected with torticollis due to cervical spine, back ...
Postural prisms
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Correction of postural misalignment: Postural prisms can be used to correct postural alignment problems, such as head, shoulder or pelvic tilt. These problems are often related to visual disorders, such as strabismus, which can affect the perception of body position.
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Balance improvement: Some people experience difficulties in maintaining balance due to visual problems. Postural prisms can help improve balance propioception by adjusting the way visual signals related to body position are processed.
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Rehabilitation after injury or surgery: After injuries or surgeries that affect visual function or the perceptual system, postural prisms can be part of a rehabilitation programme to restore normal posture and gait.
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Neuromuscular disorders and developmental disorders: In some neuromuscular or developmental disorders, such as cerebral palsy, postural prisms can be used to help children improve their alignment and balance, which can facilitate motor development.
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