Hide/Fix Macbook Pro Retina Screen Scratch
Possible methods depending on the scratch depth.

1- Fill it - for deep scratches.

Fill it with toothpaste! or professional glass filler.


  Believe it or not, toothpaste can be used to patch some screen
  scratches. Actual toothpaste, not gel or paste-mouthwash hybrids, must
  be used. Users should gently massage the paste into the scratch with
  their fingers using a circular motion. If done properly, the paste
  should adhere to the scratch and polish it away. Then, use a soft
  cloth to remove excess paste from the screen. Finally, use glass
  cleaner or a special screen cleaner to remove any additional residue.
  
  Petroleum jelly can also be applied in a similar manner, although it
  may need to be reapplied if a user happens to rub his or her screen
  and removes it from the scratch. While toothpaste is an abrasive that
  pares down a scratch, petroleum jelly fills the scratch because it
  closely matches the optical density of the LCD display.


2- Polish- for shallow scratches

Get the glass polish in any computer or similar store.

Pro..works well on shallow scratches

Con.. you will create a larger portion on your screen with lower transparency due to polishing.