Micrographia is an acquired disorder where there is abnormally small, cramped handwriting, or the progression to continually smaller handwriting. It is commonly associated with neurodegenerative disorders of the basal ganglia, such as in Parkinson's disease, but it has also been described in subcortical focal lesions. O'Sullivan and Schmitz describe it as an abnormally small handwriting that is difficult to read, as seen in the photo to the right. Micrographia is also seen in patients with Wilson's disease and Metamorphopsia, or with isolated focal lesions of the midbrain or basal ganglia.
A common feature of Parkinson's disease (PD) is to have difficulty in routine activities due to lack of overall control of movement. More specifically, patients have difficulty maintaining the scale of movements and have reduced amplitude of movement; also known as hypokinesia. These difficulties with scaling and controlling the amplitude of movement cause patients with PD to have difficulty with complex, sequential movements. This helps to explain why micrographia is a common sign and symptom of the disease. Another reason is a lack of physical dexterity.
James Parkinson may have been aware of micrographia in patients with shaking palsy (later renamed Parkinson's disease), when he described, "the hand failing to answer with exactness to the dictates of the will".
As a marker for early prognosis
Micrographia is seen in 5% of PD patients, and often appears before other cognitive symptoms. Therefore, micrographia may be an early sign for Parkinson's disease.
Micrographia may worsen when a PD patient is under-medicated, or the effects of the medication are wearing off.
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