It refers to a condition that consists of vertical misalignment of the eye.
The upward deviation of the eye usually occurs because of the slight or partial paralysis of one of the muscles that either elevate or depress the eye.
Some people define Hypertropia as a decompensation and usually deem this condition as an inherited disease.
More often than not, Hypertropia starts at the superior oblique muscle, which is one of the extra-ocular muscles that control eye movement.
Patients who suffer from this condition display the most noticeable sign of this type of strabismus (the eye turning) all the time, but in some cases, it only occurs when they’re tired or stressed.
Depending on which eye gets affected, a hypertropia of one eye could be related to a Hypotropia on the fellow eye.
Usually, this kind of strabismus affects children. In fact, some experts estimate that one out of 400 kids is likely to suffer from Hypotropia.
But in a few cases, this condition can also affect adults, although the causes that trigger Hypertropia turn out to be different from the ones that usually induce this disease in children.
Hypertropia Causes
Given the underlying reasons behind the development of this condition are different in children and adults, the article will divide this subject into two sections.
Causes of Hypertropia in Children
Several conditions are capable of causing Hypertropia. In the case of young kids, they could be Fourth Nerve Palsy, Brown Syndrome, or Duane Syndrome.
Fourth Nerve Palsy, also known as Superior Oblique Palsy or Trochlear Nerve Palsy, is a condition that consists of partial paralysis or weakening of the fourth cranial nerve.
This nerve travels from the brain stem to the superior oblique muscle, and when patients suffer from such condition, the cranial nerve becomes unable to move the eye down to the midline.
Fourth Nerve Palsy is the most common cause of hypertropia in infants and children.
Brown Syndrome refers to a rare form of strabismus, the restriction of the superior oblique trochlea-tendon complex, which results in the eye to have difficulty moving up.
Medical experts are not sure about the cause of this disorder, but some concluded that it might appear at birth or occur as the result of another underlying condition.
Duane Syndrome, also known as Duane Retraction Syndrome, is an ocular mobility disorder that features a limited ability to move the outward toward the ear.
In some cases, patients can find relatively limited their ability to move the eye inward toward the nose.
This condition occurs due to issues with the lateral rectus muscle and the sixth cranial nerve.
Oddly enough, while this disorder can cause Hypertropia, people can’t get it fixed with surgery, a procedure that usually corrects Hypertropia.
Although it’s not as common as the other causes mentioned here, suffering a Trauma that affects the eye muscle can make a kid develop Hypertropia.
But in the few cases when such thing happens, the condition gets resolved on its own.
Causes of Hypertropia in Adults
A Stroke, also known as Cerebrovascular Accident, is the most common cause of Hypertropia in grown-ups.
If the blood vessels that supply blood to the nerves that turn the eye burst or start leaking, the patient will likely develop Hypertropia.
Graves Disease, which refers to the autoimmune disease that damages the thyroid gland. This condition could negatively impact the muscles of the eye.
In this particular case, treating Graves Disease does not make the Hypertropia disappear.
Surgical Trauma, which could occur during a surgery repair cataracts, but only in rare cases.
Brain Tumor, neoplastic growths in the brain can press on the nerves that control the movement of the eye muscles can cause misalignment.
Aside from these conditions, some neurological disorders can also cause Hypertropia in adults.
Symptoms
The most noticeable sign of Hypertropia in children is the misalignment of the eyes (one of them will drift above the midline).
Some kids may try to tilt their heads, to try to align their eyes, when wanting to focus on an object.
When adult patients develop Hypertropia, people may notice their subconscious head tilt as well. In these cases, those who suffer from this condition will possibly experience double vision.
Just like other types of strabismus, the eye strain that Hypertropia causes can make headaches to occur.
Diagnosis
An ophthalmologist or an optometrist may go through the family’s medical history. The doctor can also make a physical examination to determine if the eye suffered any remarkable trauma.
They’ll perform some eye tests such as the response to light and most likely use the Snellen Chart to determine the clarity of the patient’s sight.
If the medical experts suspect of a brain tumor, they’ll likely order a Computed Tomography (CT) Scan or a Magnetic Resonance Imaging (MRI).
Hypertropia Treatment
More often than not, Hypertropia doesn’t disappear on its own. That is why medical experts often recommend three different procedures to deal with this condition.
Prism glasses: Lenses meant to correct sight issues, which can improve misalignment by holding the eyes in comfortable and relaxed alignment.
Vision Therapy: Making the eye muscle to work out by placing a patch over one eye for a fixed amount of time. That could strengthen the sight until solving the issue.
Surgery: In those case when Vision Therapy doesn’t work, Doctors resort to a surgical procedure to help the patient achieve binocularity by strengthening weak eye muscles and loosening tight ones.