The short answer is… probably no. But that doesn’t stop people from speculating…

It starts off (on 2ch, like usual), with the original poster showing a older picture of Sakura and a more recent picture of her appearing in Halloween Night. Here are before / after:

The plastic surgery in question, is the appearance of the “pouches” under the eyes, which is a really popular look amongst trendy Japanese girls.

Most of the initial comments begin with doubt, since the effect can be achieved with make up:

• There’s “eye tape”, which just lifts up the tissue a little.
• Lightening up under the eyes is really popular, it seems.
• You know absolute nothing about make up.
• If you keep saying “plastic surgery, plastic surgery”, you’ll get caught by the Stupid Police.
• This is a Hyaluronan injection. It’s not make up. You have to get this done once every few months.

And some evidence that such make up actually exists:

And still another opinion: does it really matter?

• To begin with, are having these “tear pouches” cute?
• She’s so cute, isn’t she.
• It’s okay if she does it. It’s great!
• What’s wrong with plastic surgery? In South Korea, 50% of people have some kind of plastic surgery. These antis are so desperate…
• Cuteness is righteousness.
• What the heck. She’s just cute.

But of course, all this speculation didn’t seem to matter, as it appears that she’s had a similar look way in the past: