Cochlear implantation is safe and effective in patients with MYH9-related disease

Background: MYH9-related disease (MYH9-RD) is a rare syndromic
disorder deriving from mutations in MYH9, the gene for the heavy
chain of non-muscle myosin IIA. Patients present with congenital
thrombocytopenia and giant platelets and have a variable risk of
developing sensorineural deafness, kidney damage, presenile
cataract, and liver abnormalities. Almost all MYH9-RD patients
develop the hearing defect, which, in many individuals, progresses
to severe to profound deafness with high impact on quality of life.
These patients are potential candidates for cochlear implantation
(CI), however, no consistent data are available about the risk to
benefit ratio of CI in MYH9-RD. The only reported patient who
received CI experienced perisurgery complications that have been
attributed to concurrent platelet defects and/or MYH9 protein
dysfunction. Methods: By international co-operative study, we
report the clinical outcome of 10 patients with MYH9-RD and severe
to profound deafness who received a CI at 8 institutions. Results:
Nine patients benefited from CI: in particular, eight of them
obtained excellent performances with restoration of a practically
normal hearing function and verbal communication abilities. One
patient had a slightly worse performance that could be explained by
the very long duration of severe deafness before CI. Finally, one
patient did not significantly benefit from CI. No adverse events
attributable to MYH9-RD syndrome were observed, in particular no
perisurgery bleeding complications due to the platelet defects were
seen. Patients' perioperative management is described and
discussed. Conclusions: CI is safe and effective in most patients
with MYH9-RD and severe to profound deafness and should be offered
to these subjects, possibly as soon as they develop the criteria
for candidacy.