Foreign body response within postoperative perfluoro-N-octane for retinal detachment repair: clinical features, grading system, and histopathology.

To describe the clinical and histopathologic characteristics of inflammatory deposits occurring within intermediate duration postoperative perfluoro-n-octane (PFO) for inferior retinal detachment repair. Prospective interventional case series of consecutive patients with inferior retinal detachment treated with intermediate duration postoperative vitreous cavity PFO endotamponade were analyzed by ophthalmoscopy for the presence of inflammation and white deposits. Ten consecutive samples developing white deposits were analyzed microscopically. Clinical variables were analyzed. One hundred and eighty-one eyes of 181 patients were included (mean age = 52.4 ± 14 years; mean follow-up = 29.7 ± 14 months). Fifty of 181 patients (28%) developed a characteristic foreign body response with abundant white deposits within indwelling PFO. Ten consecutive samples analyzed histologically contained abundant macrophages, the absence of additional inflammatory cells, and intracytoplasmic optically lucent inclusions. Foreign body response was associated with longer duration of PFO (P = 0.003). Perfluoro-n-octane foreign body response was not associated with age (P = 0.136), ethnicity (P = 0.101), visual outcome (P = 0.157), or persistent intraocular pressure elevation (P = 0.381). A stereotypical foreign body response occurs in ∼ 30% of patients with postoperative vitreous cavity PFO and becomes clinically apparent at 7 days to 10 days after initial placement for rhegmatogenous retinal detachment repair. The response consists almost exclusively of macrophages and does not seem to be related to either long-term intraocular pressure elevation or visual outcome. The response may be related to the duration of indwelling PFO and may limit visualization of the retina during PFO removal.