Myerson's sign also called as glabellar tap sign is a medical condition where a patient is unable to resist blinking when tapped on the glabella, the area above the nose and between the eyebrows. This is often an early symptom of Parkinson's disease, but it is can also be seen in early dementia as well as other progressive neurologic illness.It is named for Abraham Myerson,who is an American neurologist.
How to elicit glebellar tap?
Efferent - 7th CN.
Center is pons.
Clinical significance
Exaggerated glabellar tap is seen in supranuclear lesions of the corticopontine pathway and in extrapyramidal diseases
It is a sign of frontal, diffuse, or extrapyramidal disease
History of Myerson sign
It was first described by Myerson (1944) who noticed that it was constantly present in post-encephalitic Parkinsonism though not universally so in the arteriosclerotic and “senile” forms.
Wartrnburg (1952) regarded it as a definite sign of Parkinson’s syndrome, as did Doshay (1954) who gave it the eponym “Myerson’s Sign”.
Nidson (1958) confirmed its diagnostic value,
Schwab and England (1958) found it constantly in all forms of the disease.
Garland (1952) went so far as to say “For all practical purposes, this physical sign is diagnostic of the Parkinsonian state”.
How to elicit glebellar tap?
- To perform this test, the examiner repeatedly taps the glabellar prominence of the patient (area between the eyebrow)lightly with his finger.
- A normal individual will blink in response to the first two or three taps only. After that he adapts to it and blinking ceases.
- This adaptation suffers some interference in those patients with Parkinsonism .Hence prolonged tapping continues to elicit the blink response.
Efferent - 7th CN.
Center is pons.
Clinical significance
Exaggerated glabellar tap is seen in supranuclear lesions of the corticopontine pathway and in extrapyramidal diseases
It is a sign of frontal, diffuse, or extrapyramidal disease
History of Myerson sign
It was first described by Myerson (1944) who noticed that it was constantly present in post-encephalitic Parkinsonism though not universally so in the arteriosclerotic and “senile” forms.
Wartrnburg (1952) regarded it as a definite sign of Parkinson’s syndrome, as did Doshay (1954) who gave it the eponym “Myerson’s Sign”.
Nidson (1958) confirmed its diagnostic value,
Schwab and England (1958) found it constantly in all forms of the disease.
Garland (1952) went so far as to say “For all practical purposes, this physical sign is diagnostic of the Parkinsonian state”.
