Four years' experience with the minimally invasive surgical approach in cochlear implant surgery

Cochlear Implantation in Pediatric Patients: Comparison of Limited-Incision and Standard Cochlear Implantation

Today, cochlear implantation has become the standard procedure for rehabilitation of people with impaired sensory neural hearing. This procedure can be done through different techniques. The present study aimed to compare the standard technique (ST) with creation of "C" incision into the scalp with suture fixation and limited-incision technique (LIT) with creation of subperiosteal pocket without any fixation. The outcomes included operative time and complications. This retrospective study was conducted on 343 consecutive cochlear implantations. The patients received cochlear implants at our institution between 2004 and 2011. The complications were identified as "minor" or "major". All the complications and operation times were assessed for the two surgical techniques. The overall rates of complications were 4.4 % (11 out of 252) and 2.2 % (2 out of 91) for ST and LIT, respectively. The results revealed no significant difference between the two fixation techniques regarding the complications. The mean operation time was 150 ± 23.7 and 133 ± 23.12 min in ST and LIT, respectively, and the difference was statistically significant. Both ST and LIT are safe techniques with a relatively low complication rate. However, ST can be effectively replaced by LIT because of its shorter operative time.

Comparison of two different titanium couplers for an active middle ear implant

OBJECTIVE

To compare surgical methods, functional gain, and speech discrimination using two different coupling methods for an active middle ear implant. Of several couplers enabling placement of the active element at various locations, two function directly at a cochlear membrane, bypassing a missing or malformed ossicular chain. This study evaluates whether either of these methods is more beneficial.

STUDY DESIGN

Retrospective case review.

SETTING

ENT surgical clinic.

PATIENTS

Forty-seven German-speaking patients with moderate to severe mixed hearing loss.

INTERVENTIONS

Records of patients implanted with either a round window (RW) or oval window (OW) coupler and active implant were examined. Preoperative and postoperative bone and air-conduction thresholds, auditory gain, and speech perception were compared.

MAIN OUTCOME MEASURES

Functional gain, Freiburger monosyllables in quiet.

RESULTS

The range of hearing benefit shown by functional gain in patients implanted with the RW coupler (median) was between 22.5 dB (at 0.25 kHz) and 52.5 dB (2 and 3 kHz). In the OW group, improvement was similar, ranging from 21 dB (at 8 kHz) to 50 dB (1 and 2 kHz). Patients in both groups showed a similar improvement in speech recognition. Median preoperative unaided word recognition was 0% at 60 dB HL for both patient groups, improved postoperatively in both groups to median 85% correct at 65 dB HL and 95% at 80 dB HL.

CONCLUSION

Placement of an active middle ear implant using the RW and the OW coupler was found to be safe, although the surgical methods differ. Safety and efficacy of both couplers present no significant differences.

[Present state of cochlear implant treatment in adults and children]

The technique of cochlear implantation was the first method which allowed replacement of a sense organ by a (partially) implantable electronic prosthesis. By this method the cells of the spiral ganglion of the cochlea are directly stimulated by the electrodes introduced into the cochlea, bypassing the functions of the outer and middle ear as well as the cochlea. Treatment with a cochlear implant (CI) has been established over the last 20-30 years as a reliable method for restoring hearing in adults and children with severe hearing disorders and is now a routine method in many centers. For optimal results in understanding speech and for children in the speech development phase, rehabilitation must be an integral part of the total treatment and follow soon after implantation. To achieve this early diagnosis of hearing difficulties or deafness is necessary, which is simplified by a consistent hearing screening of newborns, now a statutory procedure in Germany.