Abstract
Objective
Cochlear implantation after renal transplantation is uncommon and poses unique challenges that have only recently been described in the medical literature. This work reports our experience with cochlear implantation in patients who have undergone renal transplantation.
Study Design
A retrospective review was performed.
Setting
This study was performed in a tertiary academic medical center.
Patients
Two patients were identified as having undergone cochlear implantation after renal transplantation.
Interventions
Uneventful unilateral cochlear implantations were performed.
Main Outcome Measures
Postoperative complications to include wound infection or dehiscence were reported as well as audiometric data.
Results
Cochlear implantation was completed uneventfully in both patients without postoperative complications. One patient expired two years after the procedure as a result of multiple comorbidities. Both patients achieved successful use of their device.
Conclusions
This study adds to the growing evidence that successful cochlear implantation can be achieved in appropriately selected renal transplant patients. Decision making should rely on surgical candidacy as well as assessment of surgical risk in collaboration with the transplant service.
1
Introduction
Cochlear implantation has become a widely used method of auditory rehabilitation in carefully selected surgical candidates with severe to profound hearing loss. In recent years, otologists have been making strides toward implanting candidates with chronic medical conditions, such as organ transplant recipients on long-term immunosuppressant medications, who were previously excluded because of their significant medical comorbidities and surgical risk . In particular, patients with chronic renal failure who subsequently undergo renal transplantation represent a group with an inherently increased incidence of sensorineural hearing loss but for which cochlear implantation is, as of yet, uncommon . The inherent risk is typically either a congenital otorenal genetic disturbance or because of drugs with potential ototoxic properties administered commonly to patients with renal failure .
Patients taking long-term immunosuppressants and immunomodulators represent a surgical challenge because of the potential for increased risk of postoperative complications. As this therapy attenuates the inflammatory process, the potential for wound dehiscence or other wound healing issues poses challenges for the surgeon . Infection becomes a particular concern in transplant patients not only because the surgical approach inherently places them at risk for meningitis, but the implantation of hardware also carries a risk of infection .
This manuscript seeks to add to the small but growing body of evidence that cochlear implantation in this population of renal transplant patients with inherent indications is feasible for properly selected patients with appropriate perioperative management despite their inherent risks.
2
Materials and methods
A retrospective chart review was performed on patients receiving cochlear implantation in a tertiary academic medical center between 2006 and 2009. Two patients with renal failure who had previously obtained a renal transplant were identified. After submission to the institutional review board, the board determined that the investigation qualified for exemption. Chart documentation was reviewed and reported. Open-set sentence and word discrimination were measured by the Hearing in Noise Test (HINT) and Consonant Nucleus Consonant (CNC), respectively.
2
Materials and methods
A retrospective chart review was performed on patients receiving cochlear implantation in a tertiary academic medical center between 2006 and 2009. Two patients with renal failure who had previously obtained a renal transplant were identified. After submission to the institutional review board, the board determined that the investigation qualified for exemption. Chart documentation was reviewed and reported. Open-set sentence and word discrimination were measured by the Hearing in Noise Test (HINT) and Consonant Nucleus Consonant (CNC), respectively.
3
Results
3.1
Case 1
A 47-year-old Caucasian woman underwent a living-related renal transplantation in 2001 secondary to chronic pyelonephritis after 10 months on hemodialysis. This was complicated by short-term rejection. Five years later, during a prolong intensive care admission for urosepsis, she received several ototoxic medications including vancomycin and furosemide and developed profound sensorineural hearing loss that was not responsive to steroid therapy. Preimplantation speech awareness thresholds were 105 dB on the right and nonresponsive on the left. HINT and CNC scores were both 0%.
After counseling, preoperative evaluation, and medical clearance by the transplant, nephrology, and cardiology services, an uneventful right cochlear implantation with a MED-EL Pulsar ci100 (MED-EL, Innsbruck, Austria) standard electrode was performed 18 months after the onset of the hearing loss and 6.3 years after renal transplantation. Prophylactic intravenous cefazolin was administered for 24 hours and cephalexin orally for 1 week. Upon discharge the following day, she continued her routine immunosuppressants (cyclosporine and prednisone), antibiotics (nitrofurantoin), and antivirals (acyclovir).
Her postoperative course was uneventful, and no wound infection or dehiscence was noted. She expired 2 years after her implant secondary to an unrelated cerebrovascular accident, but she did experience successful usage of her device. A Tempo+ speech processor (MED-EL, Innsbruck, Austria) was initiated, and HINT scores averaged 79% in quiet and 81% in noise 2 months postimplantation. CNC testing revealed 42% words and 70% phonemes correct. Four months postimplantation, HINT scores averaged 93.5% in quiet and 96.5% in noise, and CNC scores were 64% words and 82% phonemes correct. At 7 months, HINT scores averaged 93% in quiet and 95% in noise. Thirteen months after implantation, she was upgraded to the OPUS2 speech processor (MED-EL, Innsbruck, Austria) and demonstrated HINT scores of 100% in quiet and 90% in noise ( Fig. 1 ).
