Blepharospasm may be defined as involuntary
tight contraction of the eyelids.
That this term concerns the eyelids is indicated by the prefix "blephar-"
which refers to the eyelid. The suffix "-spasm"
refers to tight muscle contraction.
The formal definition above may be less easy for the layman to relate
to than equivalent but more colloquial descriptions such as a blepharospasm
being any abnormal tic or twitch of the eyelid. (Technically a "tic"
is a sudden, repetitive, nonrhythmic, motor movement of particular muscle
groups. Many people will also be familiar with the apperance of someone
having and uncontrolled tic or twitch, especially if visible areas such
as the face or neck are involved.)
Typical symptoms and effects involving blepharospasm
include:
- Spasms of eye closure - typically in situations of bright light,
or when concentrating, e.g. on reading or watching television
- Tiredness, irritation, or other emotional tensions can exacerbate
the symptoms
- Awareness of being observed may reduce symptoms, or their frequency
- Symptoms generally occur during active/waking hours, rather than overnight.
- If the blepharospasm progresses (gets worse), the
spasms happen more frequently - making tasks difficult, and in extreme
cases perhaps even making it very difficult for the patient to see at
all.
Many cases of blepharospasm occur arising spontaneously
or from an obscure or unknown cause. Such cases are called either benign
essential blepharospasm or primary blepharospasm.
Conversely, cases of blepharospasm due to a specific
known organic disease are known generically as secondary blepharospasm.
Examples of diseases that include or may lead to secondary blepharospasm
include:
- Multiple Sclerosis
- Some specific types of brain injury
- Atypical Parkinson's Disease
- Adverse reactions to certain drugs
- Tourette's Syndrome, and
- Cerebral palsy.
More about Ophthalmology: This section includes short definitions
of many diseases, disorders, and conditions of the eyes and visual system.
For definitions of other terms in this category, choose from the list
to the left (but note that this is not a complete/exhaustive list).
Other related pages include the diagram
of the eye, and definitions
of parts of the eye, a description
of the human retina, and definitions
of parts of the retina, and the section of short definitions
of clinical and surgical procedures re. eyes and human visual system.
For further information see also our section of Books
about Ophthalmology. |
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This Section
is about
Diseases
and Disorders of the Eyes and Visual System.
To read about other diseases, disorders, or conditions of the eye and
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