Jellyfish Entertainment shared that Hyuk has recently had eye surgery.
This is their statement:
Get well soon Hyuk 
Recover fast and Come back soon

This is their statement:
Poor Thing.Hello,
This is Jellyfish Entertainment.
We are writing to you regarding VIXX’s Hyuk.
In late August, VIXX’s Hyuk felt discomfort in his eye and visited the hospital for treatment, where he received a diagnosis of ‘retinal detachment.’
As surgery was unavoidable, everything planned on his schedule was canceled and he quickly received the surgery. After resting and discussion between the artist and our company, he has been carrying out only the minimum of his schedule and keeping his recovery as a priority.
As he is currently at a stage where he has been recovering without issue, after sufficient discussion between the company, artist, and specialist in charge of the surgery, it was decided that for the concerts on September 28 and 29, he will perform to his utmost without overdoing it.
We sincerely apologize for worrying fans by sharing this surprising news.
We consider our artist’s health to be the top priority and we are working for his quick recovery.
Thank you.
Recover fast and Come back soon