A skew eye refers to a condition where the eyes are misaligned vertically, meaning one eye is higher than the other. This is a type of strabismus, a condition where the eyes don't point in exactly the same direction. Unlike other forms of strabismus where the misalignment is horizontal, a skew deviation involves a vertical difference.
Understanding Skew Deviation
Skew deviation is a specific type of vertical strabismus. It's an acquired misalignment, meaning it develops later in life, and it isn't caused by a single muscle or nerve problem in the eye itself. Instead, it stems from damage to the parts of the brain that control eye movement, specifically prenuclear vestibular pathways and supranuclear lesions in the brainstem.
- Causes: Skew deviation results from damage to the areas of the brain that coordinate eye movement, often due to:
- Brainstem lesions
- Damage to prenuclear vestibular input to ocular motor nuclei
- Characteristics: The eyes move upward (hypertropia) in opposite directions. This often occurs with ocular torsion (eye rotation) and head tilt.
The term "skew-eyed," while informally used to describe eyes that look in opposite directions, doesn't precisely capture the neurological complexity of skew deviation. The informal usage is broader, simply implying a noticeable misalignment, while skew deviation is a diagnosable condition with specific underlying causes. Some sources use "skew-eyed" to describe a general misalignment, while others, like medical sources, use it to describe skew deviation.
There are other uses of "skew" that are unrelated to eye alignment. For example, in electronics, skew refers to a difference in signal arrival times, crucial in high-speed data transmission. This is distinct from the medical definition discussed above.
