回复：Thank you for your advice.

My mother is considering 心脏起搏器植入术 before July.  After the surgery, she needs to check into hospital within 3 months.  That's why we consider sending her back to China in a half month. We hope that she will be stabilized next January.

-Then, she may not need to come back until the end of October 2011. I is fine for her to stay in China for less than one year (bring the Dr. certificate for her illness with her). If she can not return to US within one year due to illness, she needs to apply for the Returning Resident Visa (SB-1 visa) from a US Consulate in China to come back.