3 Results
A total of 1,251 CI cases (739 males, 59.05% and 512 females, 40.95%)
were reviewed (Table 1), with CI performed on 898 right ears (71.79%),
337 left ears (26.90%), and 16 bilateral ears (1.28%); surgery age
ranged from 10 months to 63 years old, with a mean age of 7.3 years old
and a median age of 3.5 years old. All cases were operated by one
surgeon in our institution between August 2001 and March 2021.
A total of 16 SFI patients were reported from the whole CI patient
cohort (1.28%, 8 males and 8 females), who were all under 6 years old
(p < 0.05), with a mean age of 3.09 years old (Table
2). The onset of SFI symptoms ranged from 20 days to 3 years after the
implantation, affecting 14 right ears (87.5%), 1 left ear (6.25%) and
1 bilateral ear (6.25%). Gender were not significantly different.
Laterality was significant difference (p < 0.05), but
paired statistics revealed no significance (p > 0.05
for all three paired statistics).
Of the 16 children, three were cured by conservative methods (3/16,
18.75%) and thirteen by surgery (13/16, 81.25%). In the latter group,
three patients were cured by revision surgery (3/13, 23.08%) and ten
failed to be remedied by initial revision surgery but cured by
subsequent re-implantation surgery (10/13, 76.92%) (p< 0.05).
In all infectious symptoms (Table 3), skin redness was reported in 2
patients (2/16, 12.5%), one cured
by conservative method and the other by revision surgery; subcutaneous
pus formation was found in 4 patients (4/16, 25%), two cured by
conservative method and two by re-implantation surgery; punctured pus in
7 patients (7/16, 43.75%), one by revision surgery (1/7, 14.3%) and 6
by re-implantation surgery (6/7, 85.7%); the implant was exposed in 3
patients and rescued by re-implantation surgery (100%).
The results indicated no significant differences in therapeutic efficacy
between conservative and surgical treatments in skin redness or
subcutaneous pus formation but noticeable significance for punctured pus
when re-implantation was compared with either revision surgery or
conservative treatment (p < 0.05, respectively). The
revision surgery was not effective regardless of the clinical
manifestations (Figure1).
On the images by scanning electron microscopy (Figure 2),
microorganisms, consistent with Staphylococcus , and matrix were
found over the surface of the stimulator-receiver, but not on the
electrode. Large mesh can be seen in the middle of the grid.
Granulation tissue appeared in the bone groove and surrounding the
cochlear equipment, foam-like tissue cells was visualized in the
granulation tissue by the hematoxylin-eosin staining, which indicates
that the symptoms of SFI cases are chronic inflammation reaction (Figure
2).