Adie’s pupil is a neurological condition of unknown
origin with an unusual, asymmetric presentation known
as anisocoria, an inequality in the size of the pupils of
the eyes. It is believed to be a result of damage to the
nerve innervating a muscle of the eye known as the ciliary
body. Alternately, the problem may be located at the
ciliary ganglion, a kind of nerve junction structure from
which the nerve to the ciliary body runs. Accommodation,
or the adjustment of the eye for distance, is affected,
as well as pupillary dilation and contraction, the ability
of the eye’s iris to open or close in response to ambient
light. Adie’s pupil primarily affects women from 20
to 40 years of age. It is considered to be a benign condition
with no known cure. When Deep Tendon Reflexes
(DTRs) of the legs—knee and ankle jerks—are also affected,
accompanied by symptoms including localized,
discreet areas of the skin that do not sweat, postural hypotension
(low blood pressure related to sudden standing
or rising), and unsteady heart rhythms, the condition is
referred to as Adie’s syndrome.
Description
The eyes are a complex anatomical and neurological
unit. The outer surface of each eye is protected by a
cornea—a normally clear cover that initiates the bending
of light rays into the eye. Beneath the cornea lies the colorful
iris, a membrane containing two muscles capable of
contracting and dilating like the diaphragm of a camera
as it floats in the “aqueous humor.” Beneath the iris, the
lens, under the influence of the ciliary body, further bends
and directs the incoming light back to the retina, where it
is received and transferred through the optic nerve at the
back of the eye to the visual center of the brain (the visual
cortex) at the back of the head. From the visual cortex, instruction
based on whether the object of vision is near or
far, and whether the surrounding light is bright or dim,
goes back to the muscles of the eye—the ciliary body—
through the ciliary ganglion, and results in a re-shaping
of the lens (accommodation) and an opening or closing of
the pupil (pupillary reaction), as needed, in order to focus
more sharply. Under normal circumstances, brightness
and accommodation for near vision will result in contracture
of the ciliary body and the pupil, whereas darkness
and accommodation for distance normally results in a relaxation
of the ciliary body and dilation of the pupil. For
a person with Adie’s pupil, however, nerve signals arriving
at the ciliary body of one eye are weaker than to the
other eye, believed to be a result of damage to or degeneration
of the ciliary ganglion or the ciliary body. The affected
eye muscle is unable to contract, dilate, or focus
with the same strength and speed as the unaffected eye.
Relative to the opposite, unaffected eye, in normal daylight
the pupil of the affected eye will be larger whereas,
in a quickly darkened room, the affected eye will be
smaller. Furthermore, the nerve from the ciliary ganglion
to the ciliary body has 30 fibers dedicated to changing the
shape of the lens and only one fiber dedicated to dilating
the iris. As a result, a person with Adie’s pupil is even less
able to dilate their pupil than to focus. Some research
suggests that as the person ages, the ability to dilate gradually
lessens to the point that the eye may have a smaller
(constricted) pupil almost all the time.
The list of other names by which Adie’s Pupil is
known includes: Adie’s Tonic Pupil; Tonic Pupil Syndrome;
Holmes-Adie Syndrome and Adie-Holmes Syndrome;
Psuedotabes, Papillotonic Psuedotabes, and
Psuedotabes pupillotonica; Kehrer-Adie Syndrome;
Markus’ Syndrome; Weill’s Syndrome, Weill-Reys Syndrome,
and Weill-Reys-Adie Syndrome; Psuedo-Argyll
Robertson Pupil, Psuedo-Argyll Robertson Syndrome,
and Nonluetic Argyll-Robertson Pupil; Myotonic Pupil
and Myotonic Pupillary Reaction; Saenger’s Syndrome;
and, Constitutional areflexy-tridoplegia interna. These
many names derive from the lengthy history of study of
this condition, beginning in 1813, when James Ware, a
London ophthalmologist, or medical doctor specializing
in the eyes, described some of these symptoms. Dr. Adie
added to an already long list of doctors who had studied
it, when in 1931 he described the condition as self-generating.
It was first referred to as Adie’s syndrome in
1934 by the French neurologist, Jean-Alexandre Barré.
Causes & symptoms
Some external causes such as trauma or surgery to the
eye, and some internal causes such as an unknown virus,
an inflammatory condition, or a familial tendency have
been suggested. In the case of trauma or surgery, it is believed
that the damaged or cut nerve fails to regrow with all
fibers running in the same direction for proper reattachment
to the ciliary body. The propensity to affect women
between 20 and 40 years of age more than men of all ages
promoted one doctor to speculate that it may be, or related
to, an autoimmune disorder, especially when the individual
lives a stressful lifestyle and other related family members
have suffered neurological diseases or disorders. Caffeine,
a high sugar diet, or an imbalance in essential fatty acids
that are important in maintaining nerve health may also be
factors, but no studies have been identified supporting this
hypothesis. Occasionally similar symptoms are seen in
syphilitic persons; however, one source notes that as early
as 1914, syphilis was ruled out as the cause of this condition.
This unusual pupillary reflex, also known as “tonic
pupil,” because it is slow to change, may also be associated
with diabetes, alcoholism, a herpes viral infection, or a
cranial arterial condition known as giant cell arteritis.
Symptoms, in addition to the slow-to-respond, differently
sized pupil of the affected eye, may include headache, as a
result of the strain on the vision, a sensitivity to bright
lights, and loss of some reflexes, especially the knee-jerk.
Diagnosis
Diagnosis is made on the basis of a thorough history
and physical examination, followed by tests to rule out
other suspected causes according to the persons history.
An examination of the eye using a “slit lamp”—an intensely
bright lamp shielded by a shade with a slit it it—
reveals undulating, irregular, worm-like movements with
a segmented or ratcheted appearance in the iris of the affected
eye, uncoupled to movements in the iris of the unaffected
eye. A positive (hypersensitive) reaction to pilocarpine
drops, an alkaloid substance from the jaborandi
tree that causes the otherwise slow-to-constrict pupil to
constrict intensely, is considered diagnostically additive.
Treatment
No specific treatments were noted; however, treatments
that strengthen or protect the nervous system
might be helpful, treatments such as the B complex of
vitamins, antioxidants including Vitamins C and E,
alpha lipoic acid, and Superoxidedismutase (S.O.D.),
and dietary modifications of fat that have been found
helpful in multiple sclerosis, another condition due to
damage to nerve pathways affecting nerve transmission,
including intake of essential fatty acids and reduced intake
of trans-fatty acids and hydrogenated fats. Dietary
reductions in caffeine and sugar, including sugar substitutes
like aspartame, may be helpful. Lifestyle practices
that reduce stress and tone the parasympathetic nervous
system, such as yoga or massage, may be helpful.
Allopathic treatment
No specific treatments were noted, however cosmetic
use of dilute pilocarpine drops to constrict the tonic
pupil was suggested.
Prognosis
Partial recovery of function is more likely if the initiating
damage was to the ciliary body rather than to the
ciliary ganglion. As a result of the number of fibers dedicated
to each from the ciliary ganglion, recovery of innervation
to the lens controlling function is more likely than
recovery of the pupillary reactive function. One source
noted also that reinnervation may be slow, segmental and
irregular, similar to the ocular symptoms themselves.
Prevention
No preventative measures were noted.
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