From the Guidelines
When evaluating a patient with a chronic left blown pupil, I would first ask about the onset and duration of the pupillary abnormality, any associated symptoms like headache, vision changes, eye pain, or neurological symptoms, and any history of trauma, surgery, or eye medications, as recommended by the most recent guidelines 1. The physical examination should include a complete neurological assessment focusing on cranial nerves, visual acuity testing, visual field examination, and detailed pupillary examination (size, shape, reactivity to light, and accommodation) as outlined in the adult strabismus preferred practice pattern 1. Some key points to consider in the examination include:
- A careful review of the current optical correction and the presence of any ground-in or overlay prism 1
- Complete motility examination, including cover-uncover, alternate-cover testing, and prism and alternate cover measurements as well as testing for binocular fusion and stereopsis 1
- Assessment of alignment by light reflex testing (e.g., Krimsky) to compare with cover-test measurements and identification of abnormal angle kappa 1
- Evaluation for possible duction deficits suggesting a possible slipped muscle or stretched scar 1
- Strabismus patterns suggestive of cranial nerve palsy, skew deviation, or the presence of new-onset nystagmus; and proptosis or inflammatory changes that may indicate central nervous system, orbital, or thyroid conditions 1 I would check for ptosis, extraocular movements, and perform a fundoscopic examination to evaluate for the presence of papilledema or optic atrophy 1. For diagnostic workup, I would order brain imaging with CT or MRI to rule out intracranial pathology, particularly focusing on the midbrain and oculomotor nerve, as recommended by the most recent guidelines 1. Ophthalmology consultation is crucial for slit lamp examination and intraocular pressure measurement. Additional tests might include carotid ultrasound if vascular etiology is suspected, blood tests for inflammatory markers, and possibly lumbar puncture if infection or inflammation is considered 1. This comprehensive approach is necessary because a chronically dilated pupil could result from various causes including Adie's tonic pupil, oculomotor nerve palsy, pharmacologic mydriasis, or structural lesions affecting pupillary pathways.
From the Research
Questions to Ask
- What is the patient's medical history, including any previous traumatic brain injuries or conditions that may affect the brain?
- What are the patient's symptoms, including any changes in vision, headache, or other neurological deficits?
- How long has the patient had a blown pupil, and has it been constant or intermittent?
Physical Exam Examination
- Perform a thorough neurological examination, including assessment of cranial nerves, motor function, and sensory function
- Examine the patient's pupils, including size, shape, and reactivity to light
- Check for any signs of trauma, such as bruising or swelling, around the eyes or head
Diagnostic Tests to Order
- CT angiography or MR angiography to evaluate for intracranial aneurysms or other vascular abnormalities 2, 3, 4
- MRI or CT scan to evaluate for any structural abnormalities in the brain, such as tumors or hemorrhages
- Lumbar puncture to evaluate for subarachnoid hemorrhage or other conditions that may affect the cerebrospinal fluid
Considerations for a Left Blown Pupil
- A blown pupil can be a sign of increased intracranial pressure or a mass effect on the brain, such as from an aneurysm or tumor 5
- The presence of a blown pupil in combination with other neurological deficits, such as weakness or sensory changes, may indicate a more severe underlying condition
- The patient's symptoms and physical examination findings should be carefully evaluated to determine the underlying cause of the blown pupil and to guide further diagnostic testing and treatment 6