A 73-year-old male with a history of hypertension presents with gradual worsening drooping of the right eyelid and double vision that has progressed over several months. Examination of the left eye is unremarkable. Examination of the right eye demonstrates moderate ptosis, impaired extraocular movements in multiple directions, decreased corneal sensation, and right-sided miosis with impaired dilation in darkness.
Which of the following is the most likely explanation for this patient's presentation?
A. An autoantibody-mediated impairment of postsynaptic acetylcholine receptors
B. An autoimmune thyroid-associated process causing inflammation and swelling of the extraocular muscles and an increase in orbital connective tissue
C. A mass in the cavernous sinus region causing compression of nearby cranial nerves
D. An aneurysm near the origin of the posterior communicating artery with compression of a nearby cranial nerve
E. A mass affecting the right midbrain with possible involvement of nearby oculomotor pathways
Answer: (C)
A mass in the cavernous sinus region causing compression of nearby cranial nerves
The findings in this patient suggest involvement of multiple structures that pass through the cavernous sinus. Ophthalmoplegia and ptosis may reflect involvement of cranial nerves (CN) III, IV, and/or VI. Impaired corneal sensation can be attributed to involvement of CN V, specifically the ophthalmic division (V1). Right-sided miosis with impaired dilation in darkness suggests disruption of sympathetic fibers, which can also be affected by lesions in the cavernous sinus region. Lastly, the patient's chronic and gradually progressive course is most suggestive of a mass in the cavernous sinus, such as a meningioma.
(A) This describes myasthenia gravis, which can cause ptosis and diplopia, but does not explain the pupillary findings and decreased corneal sensation.
(B) This describes Graves’ ophthalmopathy, which may present with restricted extraocular movements but would not cause decreased corneal sensation or pupillary abnormalities seen in this patient.
(D) An aneurysm of the posterior communicating artery can present with a CN III palsy with impaired pupillary constriction and a dilated pupil, but would not explain the impaired corneal sensation or involvement of multiple cranial nerves.
(E) A right midbrain mass (most commonly gliomas) could affect key structures such as CN III, CN IV, and the medial longitudinal fasciculus, but would not explain the decreased corneal sensation or the impairment of pupillary dilation in darkness for this patient.
Sources:
Bireley JD, Santucci J, Li Y, Cohen DA. Clinical Reasoning: An Unusual Cause of Diplopia and Ptosis in a 67-Year-Old Woman. Neurology. 2023 Oct 17;101(16):e1646-e1651. doi: 10.1212/WNL.0000000000207676. Epub 2023 Aug 1. PMID: 37527939; PMCID: PMC10585670.
Ngnitewe Massa R, Minutello K, Mesfin FB. Neuroanatomy, Cavernous Sinus. [Updated 2023 Jul 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459244/