Cartoonist Ahmed Kabir Kishore, on Saturday, underwent ear surgery as he suffered major damage to the organ during his alleged custodial torture.
His relatives said doctors recommended the operation after assessing several medical reports.
Kishore's brother Ahsan Kabir said the cartoonist underwent surgery on his right ear at a private hospital in the capital where he has been receiving treatment since his release from jail on 4 March.
Ahsan said a medical device was placed inside Kishore's right ear during the surgery in the afternoon.
He said the device will be there for three to six months and doctors will assess the ear's condition later.
"Kishore's diabetes is under control to some degree and that is why doctors were able to perform the surgery. The pain from his leg injuries is also reducing gradually," he added.
Ahsan earlier told the media Kishore might also need cataract surgery.
The High Court, on 3 March, granted the cartoonist six-months of bail while another accused in the case, writer Mushtaq Ahmed, died in Kashimpur high-security jail in Gazipur on 25 February after being denied bail six times.
Kishore was released from prison the following day.
On Wednesday, he filed a complaint under the Torture and Custodial Death (Prevention) Act 2013 and narrated before the Dhaka Senior Special Judge's Court, in detail, the torture he was allegedly subjected to in jail.