Aberrant reinnervationĪfter the initial damage to the ciliary ganglion, the surviving fibers in the ciliary ganglion start to regrow. Why is there light-near dissociation in Adie’s tonic pupil? 1. There are equal number of fibers innervating the ciliary muscle and iris sphincterħ.There is bilateral innervation of accommodation from the cerebral cortex.There is a tactile stimulus involved in accommodation.Why is there light-near dissociation in Adie’s tonic pupil? A near add in glasses may be helpful during this time.ħ. This will improve over several months as the ciliary muscle becomes reinnervated. In the acute stage of Adie’s pupil, there is moderate to severe paresis of accommodation due to the loss of parasympathetic fibers innervating the ciliary muscle. Why may a patient with Adie’s tonic pupil have trouble with reading vision in the acute stage of this condition? 2. Increased constriction of the left pupilĦ.Excess light entering through the pupil.Why may a patient with Adie’s tonic pupil have trouble with reading vision in the acute stage of this condition? The denervated areas appear flat and do not respond to light.Ħ. Under the slit lamp, segmental contractions of the iris sphincter are seen in about 90% of Adie’s pupils and are due to contraction of the remaining areas of normally innervated iris sphincter. Segmental contraction of the iris sphincterĪdie’s tonic pupil is caused by acute denervation of the ciliary body and iris sphincter. What should be seen on slit lamp examination of the right eye? 4. Segmental contraction of the iris sphincterĥ.What should be seen with slit lamp examination of the right eye? Only the latter will demonstrate cholinergic supersensitivity and have an exaggerated constriction with dilute pilocarpine.ĥ. Testing with dilute pilocarpine is a useful way to differentiate direct damage/dysfunction of the iris sphincter (cholinergic under-sensitivity) from other post-ganglionic lesions. Within a few days of injury, cholinergic supersensitivity develops and the pupil becomes very sensitive to dilute pilocarpine. It is a result of injury to the ciliary ganglion in the retrobulbar space. This is an otherwise healthy patient that has a right tonic pupil without an identifiable cause, which is called Adie’s tonic pupil. Exaggerated constriction in the right pupil Similar degree of constriction in both eyesĤ. What would be expected if Pilocarpine 0.1% was instilled in both eyes? 2.Exaggerated constriction in the left pupil.Exaggerated constriction in the right pupil.What would be expected if Pilocarpine 0.1% was instilled in both eyes? Although a dilated pupil may be a harbinger of a compressive lesion of the 3 rd cranial nerve in an uncooperative or comatose patient, it is extremely unlikely in an alert patient with normal ocular alignment, motility, and eyelid position. Thus, a patient with an isolated dilated pupil and normal extraocular motility does not need to be investigated for a 3rd nerve palsy.Ĥ. A 3 rd nerve palsy caused by an intracranial aneurysm can cause a fixed, dilated pupil, but there will be other signs such as ptosis or at least some limitation of extraocular movements. The patient has an isolated dilated pupil with full extraocular movements and without ptosis. Which of the following is true regarding further investigations? 4. The patient should have an MRA of the head and neck to rule out a carotid dissectionģ.The patient should have an MRI of the brain to rule out a brainstem lesion.The patient should have an urgent CTA to rule out a compressive aneurysm causing a 3 rd nerve palsy.Which of the following is true regarding further investigations? If the patient had pharmacological mydriasis, the pupil should remain dilated in response to both light and a near target.ģ. The right pupil does not react to light, but constricts to a near target. The patient has anisocoria that is worse in the light, indicating that the larger, right pupil is abnormal. The right pupil constricts to a near target This patient does not have pharmacological mydriasis because: 3. The right pupil does not constrict to lightĢ.The right pupil constricts to a near target.The left pupil constricts to a near target.This patient does not have pharmacological mydriasis because: Direct damage to the iris sphincter: intraocular surgery, trauma, uveitis, ischemiaĢ.Pharmacological mydriasis: anti-cholinergic or sympathomimetic drugs.
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