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Congenital Horner's syndrome
Archives of Ophthalmology (Chicago, Ill. : 1960)
|June 1, 1980
Summary
Congenital Horner's syndrome in infants may involve postganglionic neuron damage secondary to preganglionic lesions. This explains unusual responses to mydriatic agents like hydroxyamphetamine and phenylephrine.
Area of Science:
- Ophthalmology
- Neuroscience
- Pediatrics
Background:
- Congenital Horner's syndrome is typically associated with preganglionic sympathetic nervous system lesions.
- Patients present with clinical signs including anhidrosis and abnormal pupillary responses.
- The underlying pathophysiology in neonates remains incompletely understood.
Purpose of the Study:
- To investigate the neurophysiological basis of congenital Horner's syndrome in neonates.
- To reconcile paradoxical responses to pharmacologic mydriasis in affected infants.
- To explore the role of transsynaptic dysgenesis in the developing sympathetic nervous system.
Main Methods:
- Clinical assessment of patients with congenital Horner's syndrome.
- Pharmacologic testing using hydroxyamphetamine hydrobromide to assess sympathetic neuron integrity.
- Pharmacologic testing using phenylephrine hydrochloride to evaluate adrenergic receptor sensitivity.
Main Results:
- Patients exhibited partial mydriatic failure with hydroxyamphetamine hydrobromide.
- A supersensitivity to phenylephrine hydrochloride was observed in the affected eyes.
- These findings suggest damage to the postganglionic sympathetic neuron.
Conclusions:
- The observed clinical and pharmacologic findings in congenital Horner's syndrome can be explained by aorthograde transsynaptic dysgenesis of the postganglionic neuron.
- In neonates, damage to the postganglionic neuron may be a secondary consequence of a preganglionic lesion.
- This highlights the complex developmental interplay within the sympathetic nervous system in early life.