From the Guidelines
Yes, it is possible to have residual pupillary effects after a stroke, as strokes affecting specific brain areas controlling pupillary function can cause persistent abnormalities in pupil size, shape, or reactivity to light. According to the American Heart Association/American Stroke Association statement 1, clinical signs that signify deterioration in swollen supratentorial hemispheric ischemic stroke include new or further impairment of consciousness, cerebral ptosis, and changes in pupillary size. These effects may include Horner's syndrome, Argyll Robertson pupils, or light-near dissociation, depending on which neural pathways are damaged during the stroke.
Key Points to Consider
- Damage to the sympathetic pathway can cause miosis (pupil constriction), while damage to the parasympathetic pathway may result in mydriasis (pupil dilation) 1.
- These pupillary abnormalities can persist long after other stroke symptoms have resolved and may be permanent in some cases.
- Treatment typically focuses on managing the underlying stroke rather than specifically addressing pupillary changes, though patients should be monitored by a neurologist or neuro-ophthalmologist to ensure these changes don't indicate ongoing problems or complications 1.
Monitoring and Management
- Patients with residual pupillary effects after a stroke should be closely monitored for any changes in their condition, as these changes can indicate ongoing problems or complications 1.
- A neurologist or neuro-ophthalmologist should be involved in the patient's care to ensure proper management and monitoring of any pupillary abnormalities.
- The American Heart Association/American Stroke Association recommends that patients at high risk for brain swelling should be admitted to a unit with neurological monitoring capabilities 1.
From the Research
Residual Pupillary Effects After a Stroke
- Residual pupillary effects after a stroke can occur due to the damage caused by the stroke to the brain's vascular system and its impact on the autonomic nervous system, which controls pupillary function 2.
- Automated pupillometry has been shown to be a reliable and accurate method for assessing pupillary function in stroke patients, and it may be useful in detecting residual pupillary effects 3, 4.
- Studies have found that pupillary light reflex and pupillary light-off reflex can be affected in patients with acute disorders of consciousness, including those with stroke, and may be correlated with consciousness levels 5.
- The pupillary light-off reflex, in particular, may be more sensitive to consciousness levels than the pupillary light reflex, and its clinical implications for neuromonitoring and prognostication after brain injury are worth further investigation 5.
- Diabetes is a risk factor for stroke, and diabetic patients with oculomotor palsy may experience residual pupillary effects, including binocular diplopia and abnormalities in the pupillary light reflex 6.
- The feasibility and variability of automated pupillometry in stroke patients have been studied, and the results suggest that it may be a useful tool for monitoring neurological status and predicting outcome in these patients 3, 4.