Intraocular gas dynamics after 20-gauge and 23-gauge vitrectomy with sulfur hexafluoride gas tamponade.

Purpose: The purpose of this study was to evaluate the intraocular gas dynamics after 23-gauge transconjunctival sutureless vitrectomy (TSV) as compared with 20-gauge pars plana vitrectomy (PPV).

Methods: A consecutive series of 290 eyes that experienced 20-gauge or 23-gauge vitrectomy with 25% sulfur hexafluoride (SF6) gas tamponade were retrospectively reviewed. Intraocular gas bubble size on postoperative Day 1 and Gas50, the interval to dissipate to a 50% gas fill, were evaluated.

Relationship between diabetic macular edema and peripheral Th1/Th2 balance.

Purpose: To determine whether inflammatory reactions are involved in the pathogenesis of diabetic macular edema, we examined the relationship between diabetic macular edema and the ratio of T helper 1 (Th1) to T helper 2 (Th2) cells.

Methods: Thirty-nine diabetic patients with diabetic retinopathy were evaluated at our hospital between February 2004 and February 2005. Blood samples were collected from each patient, and the ratio of CD4+ Th1 to Th2 cells (Th1/Th2) was determined by flow cytometry after fluorescent antibody staining for intracellular cytokines.