Comparison between Microscopic and Macroscopic Traumatic Hyphema due to Blunt Ocular Trauma

Purpose: this study was performed to compare complications and clinical course of microscopic and macroscopic hyphema resulting from blunt ocular trauma. methods: in a prospective observational case series during the period 21 march 2010 to 20 march 2011 all referred patient with traumatic hyphema to ophthalmic emergency ward of ahvaz, main city of southwest of iran that met inclusion criteria were included in the study and followed for at least one year. results: of 197 patients with traumatic hyphema 37 patients were excluded by exclusion criteria. 160 patients who completed examinations and follow-up protocol were enrolled in the study, 99 patients (61.9%) had microscopic and 61 patients (38.1%) had macroscopic hyphema. in microscopic group 89 patients were male and in macroscopic group 46 patients were female. clearing the anterior chamber was longer in macroscopic type (p=0.0001). intraocular pressure (iop) was significantly higher in macroscopic hyphema (p=0.007). four (6/5%) cases of macroscopic hyphema required surgery, but no patient needed surgery in microscopic hyphema (p=0.02). concomitant injuries to ocular structures like commotio retina, vitreous hemorrhage, retinal hemorrhage, macular hole and corneal epithelium defects were significantly less in macroscopic group than microscopic group (p=0.006). conclusion: despite a higher incidence of microscopic hyphema due to blunt ocular trauma, its secondary complications are rare. microscopic hyphema do not require hospitalization and short intervals of follow-up examination but require attention to concomitant ocular injury.