Pigment Release-Clearance Balance in Selective Stromal Melanin Modulation: A Mechanistic Review and Proposed P-CLEAR Framework

What determines whether pigment released after iris-directed laser exposure resolves or persists within the anterior segment? This mechanistic review examines that question through the time-dependent balance between pigment liberation and effective clearance. Drawing on evidence from pigment dispersion, trabecular-meshwork biology, aqueous-outflow physiology, and anterior-segment laser responses, the manuscript develops a conceptual release-clearance model. Clearance is treated as a dynamic biological process that may change with particulate burden, cellular activity, inflammation, and outflow function. The review introduces P-CLEAR (Pigment Clearance-Longitudinal Evaluation of Anterior-segment Recovery), a proposed framework for describing rapid-resolving, intermediate-resolving, and delayed, persistent, or discordant recovery trajectories. Its central premise is that elapsed time alone does not establish biological recovery; serial changes across pigment, inflammation, intraocular pressure, and angle/outflow findings may provide a more informative research perspective. P-CLEAR remains a hypothesis-generating framework requiring prospective validation. It does not prescribe retreatment intervals or establish numerical safety thresholds.