Hi,
as I know at the moment there is no possibility to implement a design to a Altera device without Quartus II.
At least you will need Quartus II to place and route your design, and to generate the programming files for the FPGA.
But there are different ways to generate the design. You can use written code from yourself or you can use some other tools which can generate VHDL or Verilog code.
On market there are existing some Tools for generating algorithmen. (You can define a function, verify it with the tool, and than you can generate a code for implementation)
If ORCAD provides such a function I don't know. I think Matlab/Simulink provides some functionality for the implementation. But there are also other tools on marked. It depends on your needs.