The 24-year-old sustained a serious neck injury during the first-half of the 31-24 defeat in Cardiff and underwent his first surgery on the night of the game. Still at the University Hospital in the Welsh capital, Evans has opted for a further procedure.
"Thom has been heartened by the many messages of support he has received from around the world and the surgeons are delighted with his progress," said Scotland's team doctor James Robson.
"Thom and his mum met with the surgeons last night and Thom has opted to undergo a further procedure later this week, which will enhance the surgery that has already taken place and provide further stabilisation to his neck.
"This procedure is optional and Thom could have decided to have it done at a later point, or not at all. He's decided to go ahead now and that should help with the whole recovery process.
"The same surgeons who performed the initial operation will undertake this procedure. Once he has settled from this procedure the expectation would be that he will be allowed to return home."
Evans' Scottish team mate Chris Paterson has also remained at University Hospital, Cardiff after damaging his right kidney on the day he became the first Scotland player to reach 100 caps. He is due to head home to Edinburgh at the end of the week.
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