Did you know that choroidal effusion is a side effect of Cosopt in patients post glaucoma filtration surgery?

A 74 y/o male presented to the ER for reduced visual acuity in the left eye. His history was relevant for a glaucoma filtration surgery OS done in 2018. The exam revealed an IOP of 5 mmHg on Cosopt BID and a choroidal effusion (see video and B-scan). 

Cosopt was discontinued on his initial visit and the IOP went back up to 21 mmHg with resolution of choroidals. Later on, Cosopt was started again and the choroidal effusion returned with an IOP of 6 mmHg. Once Cosopt was identified as the culprit, the patient was put on a different glaucoma medication and his IOP was maintained at an acceptable range.

A choroidal detachment is defined by the abnormal presence of fluid or blood in the suprachoroidal space, which is the potential space between the choroid and the sclera. It may be serous or hemorrhagic. Serous choroidal detachments, also known as choroidal effusions, are a frequent complication of glaucoma surgery post-operatively but can also occur later in some patients using aqueous suppressants such as Cosopt. 

Differential diagnoses may include choroidal melanoma, retinal detachment, retinoschisis, and scleral buckle.

Differentiating Rhegmatogenous Retinal Detachment from Acquired Retinoschisis and Serous Choroidal Detachment:

Conclusion: Aqueous suppressants can induce Choroidal effusions and hypotony in the postoperative phase in some patients with glaucoma drainage devices or after filtration surgery. Discontinuation of the medication usually results in the resolution of the choroidal effusions.



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