Pathophysiology and electron microscopy of melanomalytic glaucoma

Area of Science:

• Ophthalmology
• Glaucoma Research
• Cell Biology

Background:

• Melanomalytic glaucoma is a rare secondary glaucoma.
• It is associated with uveal melanoma, characterized by pigment release.
• The exact mechanism of aqueous humor outflow obstruction is not fully understood.

Purpose of the Study:

• To investigate the cellular mechanisms underlying aqueous humor outflow obstruction in melanomalytic glaucoma.
• To quantitatively assess the facility of outflow in an affected eye.

Main Methods:

• Quantitative aqueous perfusion was performed in vivo and in vitro.
• Light and electron microscopy were utilized for detailed examination.
• The cellular composition of the trabecular meshwork was analyzed.

Main Results:

• Facility of outflow was markedly diminished compared to normal.
• The trabecular meshwork was heavily infiltrated by macrophages.
• Macrophages were present on the surface and within intertrabecular spaces.
• Some macrophages appeared to be detached, phagocytic trabecular endothelial cells.

Conclusions:

• Macrophages play a significant role in obstructing aqueous humor outflow in melanomalytic glaucoma.
• The presence of phagocytic trabecular endothelial cells may also contribute to the obstruction.
• Further research is needed to elucidate the precise interactions between macrophages and the trabecular meshwork in this condition.