Exhibit 12.1 InSight Health Services Corp. Ratio of Earnings to Fixed Charges (dollars in thousands, except ratio of earning to fixed charges) Years Ended ------------------------------ Nine Months Ended Year Ended Six Months Ended December 31, December 31, March 31, 1998 June 30, 1997 June 30, 1996 1995 1994 ----------------- ------------- ----------------- ------------ ------------ (Unaudited) Ratio of earnings to fixed changes -- 1.2x -- -- 1.2x Fixed charge coverage deficiency $ 1,022 -- $ 4,093 $ 4,319 -- Fixed charges: Interest expense $ 4,665 $ 4,055 $ 1,144 $ 1,626 $ 1,206 Rent expense 4,896 6,735 2,485 5,134 5,139 ----------------- ------------- ----------------- ------------ ------------ Total fixed charges $ 9,561 $10,790 $ 3,629 $ 6,760 $ 6,345 ----------------- ------------- ----------------- ------------ ------------ ----------------- ------------- ----------------- ------------ ------------ Pretax income (loss) $(1,022) $ 1,708 $(4,093) $(4,319) $ 974 Add fixed charges 9,561 10,790 3,629 6,760 6,345 ----------------- ------------- ----------------- ------------ ------------ Earnings $ 8,539 $12,498 $ (464) $ 2,441 $ 7,319 ----------------- ------------- ----------------- ------------ ------------ ----------------- ------------- ----------------- ------------ ------------