Methyl prednisolone in double-lumen gel-saline submuscular mammary prostheses: a double-blind, prospective, controlled clinical trial. At the time of immediate breast reconstruction with submuscular implants, 76 consecutive patients (89 breasts) were randomized into two groups. One received a gel-saline, double-lumen implant with 40 cc of saline added to the outer lumen, while the other received the same implant plus 40 cc of saline and 16 mg methyl prednisolone (40 mg%). Patients were followed for a minimum of 3 years. The groups, which were matched for patient age and implant size, were evaluated at 3, 12, 24, and 36 months for capsular contracture, steroid atrophy, and other complications. With completion of the double-blind study, the patients with submuscular gel-saline implants with only saline added had an overall capsular contracture rate of 38 percent at 3 months, 38 percent at 12 months, and 44 percent at 24 and 36 months. Those with methyl prednisolone had an overall capsular contracture rate of 14 percent at 3 months, and this remained unchanged through the end of the study. The rates of all other complications were comparable. Methyl prednisolone in a dose of 16 mg in 40 cc saline (concentration 40 mg%), when used in the outer lumen of a double-lumen gel-saline implant in a submuscular pocket, is both safe and efficacious in reducing the risk of capsular contracture for a minimum of 3 years in patients undergoing immediate breast reconstruction with submuscular mammary implants. 