What is the ruling on doctors refusing the entry of a mahram with a woman, and what should the mahram do if this hospital specializes in treating the condition? And what is the ruling on a woman needing surgery where the presence of a mahram is impossible?

It is not permissible for a man to treat a woman unless there is a necessity or a need deemed valid by Islamic law, while observing the Islamic legal guidelines such as avoiding seclusion (khalwa) and the presence of a mahram, or her husband, or a trustworthy woman. The doctor must not refuse the presence of a mahram or someone who would negate the seclusion. If none of these conditions are met, there is no objection to performing the procedure due to necessity or need.