Does proving rape require four witnesses like adultery, or can it be proven by modern medical means, and does Islam accept that?

Scholars have unanimously agreed that adultery (zina) cannot be proven with fewer than four trustworthy witnesses who observed the act, based on Allah's saying: "And those who accuse chaste women and then do not produce four witnesses - lash them with eighty lashes." There is no difference between rape and adultery except that in rape, the woman is absolved of sin and the prescribed punishment (hadd). It is not valid to prove rape by modern medical means, because Islamic law has specified proof through witnesses to preserve privacy and honor. Proving rape through witnesses is possible, as a raped woman can scream and call for help, and the accused's confession of rape is sufficient.