Long deafness duration slowed, but did not block, cochlear-implant gains

Design

Single-centre retrospective cohort

Population

41 adult cochlear-implant recipients with five or more years of unaided deafness

Primary outcome

CNC word-recognition scores at 3 and 12 months

Effect

Lower scores at 3 months with 20 or more years deaf; no difference by 12 months

A common worry is that a long duration of deafness makes cochlear implantation futile. This retrospective series at a high-volume centre examined 41 adults with at least five years of unaided deafness, grouped as 5 to 9, 10 to 19, and 20 or more years.

At three months, those with 20 or more years of deafness had lower word-recognition scores than the shorter-duration groups — but by 12 months the differences had disappeared. The group that fared worst was defined not by duration but by physiology: patients with no measurable preoperative hearing thresholds were more likely to become device non-users or fail to achieve open-set speech.

The counselling message is twofold. A long duration of deafness is not in itself a reason to withhold implantation, though early gains may be slower; and absent preoperative hearing thresholds, rather than years deaf, mark the subgroup to counsel most carefully about limited benefit.

• Retrospective series of 41 adults with five or more years of unaided deafness.
• Those with 20 or more years improved more slowly at three months but caught up by 12 months.
• No measurable preoperative hearing thresholds predicted non-use or failure to reach open-set speech.
• A long duration of deafness alone is not a reason to withhold implantation.
• Counsel most carefully where preoperative thresholds are absent, not simply where deafness is long-standing.

Why it matters

It pushes back on using deafness duration alone to deny implantation, redirecting the risk conversation to preoperative hearing thresholds.

Don't overread it

A small, single-centre retrospective series; it describes outcomes rather than proving which patients will benefit.

The statistics, in plain English

That the group difference seen at three months was gone by twelve suggests the main effect of long deafness is slower early adaptation; with only 41 patients, small subgroups mean the outcome estimates are imprecise.

Read the rest in the app

You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.

Get Daily Doctor — free

Scan to keep reading on your phone. No account needed to start.