What is the likely diagnosis for a patient who presents with bilateral Krukenberg spindles?

Bilateral Krukenberg spindles are associated with pigmentary dispersion syndrome, making it the most likely diagnosis in this scenario. These spindles are characterized by the deposition of pigment on the corneal endothelium, typically arising from the iris or the ciliary body, which is a hallmark of this syndrome.

In pigmentary dispersion syndrome, there is a breakdown of the blood-aqueous barrier, allowing pigment granules to enter the anterior chamber and subsequently deposit on the cornea. Patients may be asymptomatic but can develop elevated intraocular pressures and eventually glaucoma. The observation of bilateral Krukenberg spindles is pathognomonic and serves as an important clinical sign that guides the clinician toward this diagnosis.

Other options typically do not present with these spindles. Mutual effusion syndrome is not a commonly recognized ophthalmic condition, and while misdiagnosed glaucoma may occur, it would not specifically manifest as Krukenberg spindles. Similarly, corneal dystrophies are genetic conditions affecting the corneal layers but are unrelated to pigment dispersion phenomena. Thus, the presence of bilateral Krukenberg spindles is a clear indicator of pigmentary dispersion syndrome, supporting the provided diagnosis.