Unilateral Intraocular Pressure Elevation in Patient With Glaucoma: JAMA Ophthalmology Clinical Challenge
A 52-year-old man with a history of severe primary open-angle glaucoma in both eyes and elevated intraocular pressure (IOP) in response to topical corticosteroids presented with an IOP above target of 19 to 23 mm Hg OS. He also had mild chronic macular edema in both eyes after remote cataract surgery and vitrectomy with membrane peel in both eyes. Two years prior, he underwent Baerveldt...
A 52-year-old man with a history of severe primary open-angle glaucoma in both eyes and elevated intraocular pressure (IOP) in response to topical corticosteroids presented with an IOP above target of 19 to 23 mm Hg OS. He also had mild chronic macular edema in both eyes after remote cataract surgery and vitrectomy with membrane peel in both eyes. Two years prior, he underwent Baerveldt tube shunt in his left eye, and his IOP since surgery had been 8 to 14 mm Hg.
Ophthalmic medications on presentation were timolol eye drops twice daily, brinzolamide-brimonidine eye drops 3 times daily, bimatoprost eye drops every night at bedtime, bromfenac eye drops once daily, and fluorometholone eye drops twice daily in both eyes.
During his visit, the patient complained of severe physical exhaustion, syncopal episodes, dysphagia, and sinus congestion. On external examination, he had diffuse facial edema and erythema without proptosis. Slit lamp examination showed mild chemosis and hyperemia in both eyes and a patent Baerveldt tube ostium in the midanterior chamber with normal blebmorphology without a tense capsule. A 24-2 Humphrey visual field showed new glaucoma progression in the left eye.
Diagnosis was made of Elevated IOP due to elevated episcleral venous pressure secondary to superior vena cava syndrome and a systemic workup, including chest imaging was performed.
Systemic workup, including chest imaging (B), is the best choice given the patient’s symptoms and examination findings. The patient’s facial edema, sinus congestion, and dysphagia point to superior thoracic venous outflow obstruction. His elevated OP can be explained by elevated episcleral venous pressure (EVP). EVP contributes to IOP. However, it is not typically measured clinically because of difficulty in obtaining accurate, noninvasive measurements. EVP is determined by vascular tone and gravity and is independent of IOP and aqueous production.
Examination findings of elevated EVP beyond elevated IOP include dilated, tortuous episcleral vessels that do not blanch with topical constrictors, chemosis, and blood in the Schlemm canal on gonioscopy. The differential diagnosis for elevated EVP includes orbital varix, SturgeWeber syndrome, direct and indirect carotid cavernous fistulas, cavernous sinus syndrome, and superior vena cava (SVC) syndrome. Additionally, behaviors such as playing a high-resistance wind instrument, wearing a tight tie and performing postural inversions8 are thought to be associated with increased EVP.
In this patient, SVC syndrome best accounts for his presentation. Examination findings typical of SVC syndrome include plethora, orbital congestion, cyanosis, proptosis, and increased IOP that worsen with recumbent positioning. The mechanism of elevated IOP in SVC syndrome is increased venous pressure in the jugular vein causing retrograde congestion in the ophthalmic veins and elevated EVP. SVC syndrome may be caused by neoplasms, aortic aneurysms, or central venous stenosis secondary to indwelling catheters and stents. Given the subacute presentation and severe fatigue in this patient, neoplastic etiology appears most likely.
Patient Outcome: Workup for this patient included computed tomography chest scan, which revealed a large mediastinal neoplasm encasing the SVC. The left internal jugular vein was substantially more stenotic than the right. Subsequent supraclavicular lymph node biopsy showed diffuse large B-cell lymphoma. The patient received chemotherapy and radiation treatment. His IOP after treatment returned to the baseline of 13 to 16 mm Hg. Appropriate workup of systemic symptoms in this patient with elevated EVP due to a mediastinal mass resulted in a diagnosis and subsequent treatment, which not only lowered his IOP but also likely prolonged his life.
Source: Chavez KE, Cretara EA, Davis RE. A Case of Unilateral Intraocular Pressure Elevation in a Patient With Glaucoma. JAMA Ophthalmol. 2023;141(1):93–94. doi:10.1001/jamaophthalmol.2022.4735
