Subcutaneous emphysema around the cochlear implant: Two distinct etiologies

Isra Aljazeeri; Fida Almuhawas; Abdulrahman Hagr

doi:10.4103/sjoh.sjoh_47_22

CASE REPORT

Year : 2022 | Volume : 24 | Issue : 4 | Page : 168-171

Subcutaneous emphysema around the cochlear implant: Two distinct etiologies

Isra Aljazeeri¹, Fida Almuhawas², Abdulrahman Hagr²
¹ King Abdullah Ear Specialist Center, College of Medicine, King Saud University Medical City, King Saud University, Riyadh; ENT Department, Aljaber Ophthalmology and Otolaryngology Specialized Hospital, Ministry of Health, Ahsa, Saudi Arabia
² King Abdullah Ear Specialist Center, College of Medicine, King Saud University Medical City, King Saud University, Riyadh, Saudi Arabia

Date of Submission	01-Oct-2022
Date of Decision	11-Nov-2022
Date of Acceptance	13-Nov-2022
Date of Web Publication	30-Dec-2022

Correspondence Address:
Dr. Isra Aljazeeri
King Abdullah Ear Specialist Center, College of Medicine, King Saud University, P.O. Box 245, Riyadh 11411
Saudi Arabia

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/sjoh.sjoh_47_22

Abstract

Subcutaneous emphysema is usually induced by trauma, infection with gas-forming organisms, or surgical interventions. Few cases have been reported with subcutaneous emphysema after cochlear implantation. Here, we present two cases of subcutaneous emphysema with two distinct etiologies. One case presented with recurrent, bilateral, self-limiting, and mild swelling around the internal receiver stimulator of the cochlear implant. In-depth history taking of this patient revealed that each episode of this swelling was preceded by an upper respiratory tract infection, associated with forceful sneezing and coughing. This patient was managed conservatively. The other case had a long history of otorrhea, for which he did not seek medical attention. The patient presented with painful swelling over the internal receiver stimulator. Moreover, the underlying cause of the subcutaneous emphysema was found to be a cholesteatoma. This patient was managed surgically with the preservation of the device.

Keywords: Cholesteatoma, cochlear implantation, Saudi Arabia, subcutaneous emphysema, valsalva

How to cite this article:
Aljazeeri I, Almuhawas F, Hagr A. Subcutaneous emphysema around the cochlear implant: Two distinct etiologies. Saudi J Otorhinolaryngol Head Neck Surg 2022;24:168-71

How to cite this URL:
Aljazeeri I, Almuhawas F, Hagr A. Subcutaneous emphysema around the cochlear implant: Two distinct etiologies. Saudi J Otorhinolaryngol Head Neck Surg [serial online] 2022 [cited 2023 Jun 4];24:168-71. Available from: https://www.sjohns.org/text.asp?2022/24/4/168/366336

Introduction

Nowadays, cochlear implant is considered one of the most preformed neuro-otological surgeries. One of the rare complications with cochlear implantation is subcutaneous emphysema, which is air collected in the subcutaneous tissues. An incidence of 0.4%–0.21% has been reported for subcutaneous emphysema in cochlear implanted patients.^[1],[2] Various etiologies have been theorized to be the cause of this complication. Some authors have suggested the compressed air-powered mastoid drills as an air introducing factor.^[3] In another article, a case was illustrated with an emphysema that necessitated surgical exploration, revealing an anterior inferior external auditory canal defect. The location of this defect was suggestive of a negative pressure produced by the temporomandibular joint movement to be the etiology behind air collection.^[4] A case was reported in which a patient performed sever Valsalva maneuver in the early postoperative period. This was followed by not only subcutaneous emphysema but also pneumocephalus. The Valsalva maneuver performed by the patient was suggested as the etiology of this air leak.^[5] The reported management options included conservative management, aspiration, pressure dressing, antibiotics, and sealing of any defects.^{[3],[4],[5],[6]}

Case Reports

Case Report 1

Nine-year-old girl case of bilateral sensorineural hearing loss managed successfully by bilateral cochlear implant when she was 2 years old. She presented with recurrent episodes of painless swelling over the internal receiver stimulator (IRS). The patient did not have any associated fever or otitis media nor change in the quality of hearing. These episodes happened yearly in winter season and resolved spontaneously over about a month. Reviewing the patient's history in detail revealed that each episode was preceded by sever flu associated with vigorous coughing and sneezing. The past episode was unusually prolonged and did not improve over 2 months. Upon examination, a debatable fluctuating swellings were noticed bilaterally over the IRS site, more in the right side. The skin overlying the swelling was normal, with no redness, no hotness, no tenderness, and no fistula formation. Otomicroscopic examination showed no signs of infection.

Audiologic evaluation showed stable map with within normal hearing level. Impedance of all electrodes was within normal and compound action potentials elicited normal waves. Computed tomography (CT) imaging showed subcutaneous emphysema around the IRS and the magnet [Figure 1]a and [Figure 1]b. The air around the device could not be traced to the site around the electrode array, suggesting a one-way valve effect [Figure 1]c.

Figure 1: CT image showing subcutaneous emphysema around the IRS and the magnet in (a) axial view and (b) coronal view. (c) There was no air around the electrode array. CT: Computed tomography, IRS: Internal receiver stimulator

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The patient was managed with 2 weeks of prophylactic antibiotics and pressure dressing with removal of the right external cochlear implant (CI) device. The swelling resolved completely in 1 month. To ensure the resolution of the emphysema, ultrasound (US) imaging was performed [Figure 2].

Figure 2: US image showing no air collection

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Case report 2

Twenty-five years old, postlingual male diagnosed with progressive sensorineural hearing loss. He received right cochlear implantation when he was 19 years old. He was doing well on the implant and stopped coming to follow-up visits after reaching a stable satisfactory hearing level. Six years after implantation, he presented with history of minor head trauma followed by painful swelling over the magnet site and decrease perception to the sounds. He also has noticed foul smelling discharge from the ear canal of the operated ear. On examination, his external auditory canal was filled with keratin, polyps, and purulent discharge. CT temporal bone imaging showed destructive soft tissue density filling the mastoid cavity, connected to an eroded area of the posterior external auditory canal. There was minimal middle ear involvement. The area around the IRS showed subcutaneous emphysema [Figure 3].

Figure 3: (a) CT image axial view showing (A) subcutaneous air collection close to the internal receiver stimulator, (B) CT image coronal view showing soft tissue density in the mastoid air cells superior to the external auditory canal while the mesotympanum and hypotympanum are clear

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The patient was managed by topical and oral broad-spectrum antibiotics for 2 weeks. The swelling and the discharge improved after the course of antibiotics. Audiologic evaluation was performed then after showing within normal hearing level, impedance, and compound action potentials [Figure 4]. Surgical removal of the cholesteatoma and posterior canal reconstruction was achieved without the need to remove the implant.

Figure 4: Cochlear implant-aided audiologic evaluation of the patient showing mild hearing loss with poor word recognition score bilaterally

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Discussion

Subcutaneous emphysema is one of the rare complications of cochlear implantation. This study presents possible two different etiologies for subcutaneous emphysema.

The first case presents a case with possible one-way valve passage that allows egress of the air into the subcutaneous area with no escape. This can explain why the episodes were always preceded with vigorous coughing and sneezing that would result in Valsalva effect that increases the pressure in the middle ear. The concern with this situation is that if the air is escaping into the area around the IRS, the pathologic organisms can be carried along. The other concern is that iatrogenic defect can happen in the scalp during cochlear implantation. If such defects are present in this patient, the air can escape into the intracranial area leading to more worrisome situation. Fortunately, both of these concerns were not seen in our case to date. For this reason, a more conservative management is justified.

Other possible options can include either producing an area for the air egress such as a myringotomy with tube insertion or blocking the area of possible air passage by performing a blind sac procedure. These options would be more appropriate if the patient presented with any concerning conditions. The US imaging was used for following up of this patient to decrease radiation exposure.

The second case presents a case complicated with cholesteatoma. The fact that the middle ear is not involved and there is no Prussak's space involvement, also the fact that the cholesteatoma is connected to the canal defect point to the possibility that the cholesteatoma is most likely a result of iatrogenic external auditory canal injury during cochlear implantation. The presence of air with this infected cholesteatoma is worrisome for an air-producing organism infection. A broad-spectrum covering antibiotic was chosen to cover this possibility.

Previous studies have illustrated cholesteatoma in cochlear implant patients due to iatrogenic external canal injury.^{[7],[8],[9],[10]} The case presented in this study had normal examination in the early postoperative period. The lack of long-term follow-ups led to late presentation with infected cholesteatoma. The importance of regular follow-up postoperatively cannot be over emphasized.

Preservation or removal of the device in the middle ear exploration surgery for removal of the cholesteatoma is a controversial matter. Argument can be made that removal of the device can help in a better visualization of the surgical field with lower surgical time. A well-functioning cochlear implant encourages the surgeon toward trial of preserving the device in place to prevent the intracochlear injury with explantation and reimplantation. However, the surgical removal of cholesteatoma is a complex procedure without the present of an easily extrudable cochlear implant device. The preservation of the cochlear implant device would not be always possible even if tried.^[11] The other concern with the preservation of cochlear implant, is the increased possibility of ascending infection which puts the patient in risk for meningitis.^[12] Nevertheless, preservation of the device with cases of acute mastoiditis and surgical site infections has not shown any ascending infections.^[13],[14]

It is common for postcochlear implants to present with mild swelling over the implant. Since most of these patients do not undergo radiological evaluation, a large number of emphysemas can go undetected. The use of US can help in detecting these patients without the risk of radiation exposure.

Conclusion

Subcutaneous emphysema can be a rare complication with cochlear implantation with various etiologies. US is a cheap, easy, and safe method for detecting emphysema. The prevalence of emphysema could be underestimated due to the lack of radiological evaluations. Management decision needs to be customized according to the patient's situation.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	Kim CS, Oh SH, Chang SO, Kim HM, Hur DG. Management of complications in cochlear implantation. Acta Otolaryngol 2008;128:408-14.
2.	Tarkan Ö, Tuncer Ü, Özdemir S, Sürmelioğlu Ö, Çetik F, Kıroğlu M, et al. Surgical and medical management for complications in 475 consecutive pediatric cochlear implantations. Int J Pediatr Otorhinolaryngol 2013;77:473-9.
3.	Dayasena RP, Soodin D, Habaragamuwa BW, Ganthune S. Surgical emphysema and pneumomediastinum following mastoidectomy. Ceylon Med J 2007;52:146-7.
4.	Chhabra N, Rezaee RP, Tucker HM, Megerian CA. Subcutaneous emphysema after otologic surgery: A case report. Am J Otolaryngol 2012;33:489-92.
5.	Gillett D, Almeyda J, Whinney D, Savy L, Graham JM. Pneumocephalus – An unreported risk of Valsalva's manoeuvre following cochlear implantation. Cochlear Implants Int 2002;3:68-74.
6.	Khatwa MM, Khan A, Osborne J. Surgical emphysema: A rare complication following cochlear implantation. Cochlear Implants Int 2007;8:158-61.
7.	Kaila R, Evans RA. Cochlear implant infection due to cholesteatoma. Cochlear Implants Int 2005;6:141-6.
8.	Rangabashyam M, Poh SS, Low WK. Electrode array extrusion through the posterior canal wall presenting as a delayed post-cochlear implant complication. Cochlear Implants Int 2015;16:341-4.
9.	Bassim MK, Zdanski CJ. Electrode extrusion through the tympanic membrane in a pediatric patient. Otolaryngol Head Neck Surg 2007;137:680-1.
10.	Bhatia K, Gibbin KP, Nikolopoulos TP, O'Donoghue GM. Surgical complications and their management in a series of 300 consecutive pediatric cochlear implantations. Otol Neurotol 2004;25:730-9.
11.	Low WK, Pok WN, Ng WN, Tan J. Accidental explantation of a cochlear implant in a child who developed cholesteatoma as a late complication of cochlear implantation. Case Rep Otolaryngol 2020;2020:6353706.
12.	Summerfield AQ, Cirstea SE, Roberts KL, Barton GR, Graham JM, O'Donoghue GM. Incidence of meningitis and of death from all causes among users of cochlear implants in the United Kingdom. J Public Health (Oxf) 2005;27:55-61.
13.	Zawawi F, Cardona I, Akinpelu OV, Daniel SJ. Acute mastoiditis in children with cochlear implants: Is explantation required? Otolaryngol Head Neck Surg 2014;151:394-8.
14.	Low WK, Rangabashyam M, Wang F. Management of major post-cochlear implant wound infections. Eur Arch Otorhinolaryngol 2014;271:2409-13.