Clinical Manifestations of Myasthenia Gravis

Ptosis in Myasthenia Gravis

      Myasthenia gravis is characterized by fluctuating weakness in skeletal muscle and this weakness will increase when it is active. Patients will feel very weak muscles in the day and this weakness will be reduced if the patient rested. Usuallyinitial complaint is a specific muscle weakness, not ordinary  muscle weakness  and the condition deteriorated typically fluctuate for several hours. Not apparent in the morning and usually worsens as the day progresses. It also varies over several weeks or months, with exacerbations and remissions.

Symptoms and signs of Myasthenia gravis (MG), which appears as follows:

• Symptoms of the Eye
       Among the patients, 75% initially complained of eye disorders, particularly ptosis and diplopia. Finally, 90% of patients with MG develop ocular symptoms. Maybe unilateral or bilateral ptosis, and will switch from eye to eye. Ptosis usually the most prominent and occurred after blinking a few times. Ptosis that is one symptom, oculomotor nerve paralysis, often a major complaint of people with myasthenia gravis. Even though in myasthenia gravis, muscle levator palpebral obviously lame, but there are times when the ocular muscles are still moving normally. But in the later stages of ocular muscle paralysis both sides will complete ptosis myasthenia gravis. Bulbar muscle weakness are also common, followed by weakness in flexion and extension of the head. In the case of unilateral ptosis, eye ptosis will not run if the eye ptosis ptosis opened by using a finger (Hering phenomenon). Involvement outside of the eye muscles do not follow a specific pattern. Any disturbance of ocular motility obtained with ptosis and pupillary reflexes normal obtained, should direct suspicion on myasthenia gravis MG.

• Symptoms and signs of general
       Muscle weakness occurs on the face, extremities, oropharyngeal and respiratory, with no signs of other neurological deficits, such as impaired sensory, physiological changes in tendon reflexes, or muscle atrophy. Weakness that occurs in the muscles of the extremities is more like a weakness of the proximal myopathy distal muscle weakness. Weakness of the muscles of the extremities in particular arising as a rare phenomenon and its prevalence is only 10%.

Classification of Myasthenia Gravis
According to the Myasthenia Gravis Foundation of America (MGFA), myasthenia gravis can be classified as berikut7:
a. Class I
Weakness of ocular muscles, weakness at the time of closing the eyes, and the strength of other muscles is normal.
b. Class II
There ocular muscle weakness is getting worse, and the presence of mild weakness in other muscles  than ocular muscles.
c. Class IIa
Affect the axial muscles, limbs, or both. There is also a mild weakness of the muscles of oropharyngeal.
d. Class IIb
Affects the muscles of oropharyngeal, respiratory muscles or both. Weakness of the muscles of the limbs and axial muscles lighter than class IIa.
e. Class III
There is a severe weakness in the ocular muscles. While muscles other than ocular muscles had moderate weakness.
f. Class IIIa
Affects the muscles of a limb, axial muscles, or both predominantly. There is a mild oropharyngeal muscle weakness.
g. Class IIIb
Affect the oropharyngeal muscles, respiratory muscles, or both predominantly. There is a weakness of the muscles of a limb, axial muscles, or both in a mild degree.
h. Class IV
The muscles other than ocular muscles experience severe weakness in degrees, while the ocular muscles experiencing weakness in varying degrees.
i. Class IVa
Predominantly affects the muscles or the limbs and axial muscles. Oropharyngeal muscle weakness experienced in a mild degree.
j. Class IVb
Affect the oropharyngeal muscles, respiratory muscles or both predominantly. In addition, there is a weakness in the muscles of the limb, axial muscles, or both with a mild degree. Patients use a feeding tube without intubation.
k. Class V
Patients intubated, with or without mechanical ventilation.
Usually the symptoms of myasthenia gravis ptosis and strabismus crate will not appear in the morning. In the afternoon or in hot weather, the symptoms will appear more clearly. On examination, muscle tone seems somewhat decreasing.
Myasthenia gravis can also be classified more simply as follows:
a. Myasthenia gravis with mild ptosis or diplopia.
b. Myasthenia gravis with ptosis, diplopia, and weakness of the muscles for chewing, swallowing, and speaking. Muscles tubuhpun members can come to be weak. Breathing is not impaired.
c. Myasthenia Gravis which takes place rapidly by weakness of the muscles oculobulbar. Breathing is not impaired. Patient can die.



RELATED ARTICLES

•    Myasthenia Gravis
•    Pathophysiology of Myasthenia Gravis
•    Diagnosis of Myasthenia Gravis
•    Medical Treatment and Therapy of Myasthenia Gravis


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