SUBMITTED 6 FEB 22 1 REVISION REQ. 6 APR 22; REVISION RECD. 15 MAY 22 2 ACCEPTED 8 JUN 22 3 ONLINE-FIRST: JUNE 2022 4 DOI: https://doi.org/10.18295/squmj.6.2022.044 5 6 Outcome of Cochlear Implantation in Deaf Children with Co- 7 Existing Otitis Media with Effusion 8 A comparative study 9 Sami Al Habsi,1 *Khalid Al Zaabi,2 Ammar Al Lawati1 10 1Department of Otolaryngology, Head & Neck Surgery, Al Nahdha Hospital, Muscat, 11 Oman; 2Department of Surgery, Sultan Qaboos University Hospital, Muscat, Oman 12 *Corresponding Author’s e-mail: khaboore21.ka@gmail.com 13 14 Abstract 15 Objective: Cochlear implantation (CI) is the definitive treatment for profound hearing 16 loss in children and adults. Operating on an infected ear is considered a challenge; the 17 institution of cochlear implant the presence of otitis media with effusion (OME) prior 18 to CI surgery has created a debate among neuro-otologists: treat the OME first or go 19 ahead with surgical intervention. This study was conducted to determine whether 20 cochlear implantation in patients with OME at the time of surgery has any influence 21 on the procedure, post-operative complications and surgical outcome. Methods: 22 Retrospective descriptive analysis of data collected from records of patients who 23 underwent CI in a tertiary care hospital from 2000-2018 was done. The age targeted 24 was 6 months to 14 years old, excluding all adults, and those who had their operations 25 outside the chosen institution. Results: Out of 369 children, 175 had OME preceding 26 surgery compared to 194 who did not have OME. Intra-operative oedematous 27 hypertrophied middle ear mucosa was observed only in OME patients (n=18, P 28 <0.050). Moreover, among the OME patients, six cases developed mild intra- 29 operative bleeding compared to only one case from non-OME group (P <0.050). 30 Overall, there was no significant difference in post-operative surgical complications 31 between the two groups (P >0.050). Conclusion: The presence of OME is associated 32 with intra-operative technical difficulties, such as impaired visualization and bleeding. 33 mailto:khaboore21.ka@gmail.com However, OME is not determinative on performing cochlear implantation in terms of 34 post operative complications and outcome. Therefore, there is no need to delay the 35 implantation until the OME resolves. 36 Keywords: Cochlear implantation, otitis media with effusion, children, and 37 sensorineural hearing loss 38 39 Advances in Knowledge 40 - The study highlight that CI shouldn’t be delayed due to the existing OME as it 41 is not statistically influence the treatment of deaf children with CI. This 42 information is vital as early institution of CI is decisive in successful 43 rehabilitation of deaf children and the presence of OME should not delay 44 implantation which might affect the outcome. 45 46 Applications to Patient Care 47 - This study shows that the delay is not justified, so CI could be done as soon as 48 the patient is diagnosed with profound SNHL regardless the finding of OME 49 50 Introduction 51 Otitis media with effusion (OME) is a common problem encountered in pediatric age 52 group. It is defined as presence of fluid (effusion) in the middle ear cavity without 53 infection.1 The nature of the fluid is either mucoid or serous. It is managed either by 54 watchful waiting, medical therapy or surgery. Cochlear implantation (CI) is the 55 standard of care in management of children with profound sensorineural hearing loss 56 (SNHL).2-15 In our health care system, children with a confirmed diagnosis of 57 profound SNHL will be evaluated for potential CI. The indications of CI in our study 58 group were congenital, infection (e.g. meningitis) and or syndromic. The incidence of 59 complications among patients with OME who undergo CI ranges from 1.7 to 4.1%.3,16 60 61 Management of OME in children who are the candidates for the CI is the subject of 62 debate on whether the OME should be treated prior to CI or not. The presence of 63 OME has been reported to increase the risk of post-operative surgical site infection, 64 meningitis and device extrusion4-11 as well as impaired visualization and bleeding in 65 the presence of inflamed middle ear mucosa, leading to a high risk of complications in 66 the post-operative period.5,6,7 Some surgeons insert a ventilation tube (VT),7 while 67 others treat it medically, with some operating regardless.4-6,8-11 This study describes 68 our experience of CI in patients with OME prior to and at the time of surgery. The 69 effect of OME on the procedure, post-operative complications and surgical outcome 70 were evaluated and presented. 71 72 Methods 73 This was a single-center retrospective case control study of consecutive pediatric 74 patients presenting with profound hearing loss and underwent cochlear implantation 75 from 2000 to 2018 in Al Nahdha hospital, Muscat, Oman. All data was collected from 76 electronic medical records. 77 78 We collected patient characteristics including age, gender, and demographic profiles. 79 The data related to assessment included clinical examination findings, complete 80 otological, head and neck examination in an outpatient setting. Audiological test 81 results such as Tympanometry, Brainstem auditory evoked response audiometry 82 (BAERA) and the details of Imaging (High resolution temporal bone computed 83 tomography (CT), magnetic resonance imaging (MRI)) were also collected. The study 84 included all pediatric patients aged 6 months to 14 years. Those who were above 14 85 years, those who presented after the first surgery done elsewhere then re-implanted in 86 our center and those with incomplete data were excluded. The surgery was performed 87 by our otology team in the department of ENT including 3 senior otologists. 88 89 The total sample size was 369 patients who were divided into 2 groups: those with 90 OME and those without. Patients who were suspected to have OME during the 91 clinical examination were subjected to acoustic immittance tympanometry. 92 Radiological evidence of middle ear opacification on the CT scan was also considered 93 for further workup. B type flat curve on were considered positive of OME. The 94 treatment and follow up of these children were collected and analyzed. All children 95 who had OME prior to surgery underwent a period of watchful waiting or 96 symptomatic treatment in terms of nasal spray or antihistamine syrup. There was no 97 treatment given intra-operatively or post-operatively for these children. Surgical steps 98 included post-auricular incision, followed by cortical mastoidectomy. Surgeons 99 performed a posterior tympanotomy followed by a round window or cochleostomy 100 approach, based on the anatomical variations. Device function was tested intra- 101 operatively using neural response telemetry (NRT) and stapedial reflex in most of the 102 patients. Intra-operative findings and post-operative surgical outcomes were observed 103 in both groups. Intra- or post-operative portable X-ray was used to confirm the correct 104 placement of the electrode in all patients. The Statistical Package for Social Sciences 105 (SPSS), version 20 (IBM Corp., Armonk, NY) was used in data analyses. A P value 106 of <0.05 was considered statistically significant. Ethical approval was obtained from 107 the research and ethical committee at the hospital. 108 109 Results 110 The study included 369 patients. 195 (52.8%) were male and 174 (47.2%) female. 111 The OME group consisted of 175 (47.4%) children with 92 males (24.9%) and 83 112 females (22.5%). In the non-OME group, there were 194 (52.6%) patients in total, 113 103 (27.9%) were male and 91 (24.7%) were female. There was no statistically 114 significant difference between the two groups (P = 0.5). In the OME group, 42 (24%) 115 of patients were less than 2 years old at the time of evaluation and surgery whereas 116 133 (76%) children were 2 years old and older at the time of presentation. All the 117 children in both the age groups with OME had received treatment (medical or 118 surgical) prior to cochlear implantation, however, all of them scheduled for CI 119 regardless of treatments received. 120 121 The mean age at implantation was 3.2 years with no statistical significant difference 122 between the two groups. Intra-operative findings and post-operative complications 123 with surgical outcomes were analyzed. The average operative time was 2.5 to 3 hrs. In 124 the OME group, middle ear inflammation was encountered in only 2 (1.1%) cases 125 compared to 1 (0.5%) case in the non-OME group (P = 0.46). Granulation tissues 126 were seen in only 1 case (0.6%) in OME group compared to 2 (1%) cases in non- 127 OME group, with no statistically significant difference. Hypertrophied mucosa was 128 observed in 18 cases (10.3%) in the OME group compared to no cases in the non- 129 OME group. This was statistically significant (P <0.001). Intra-operative minimal 130 bleeding was encountered in 6 (3.4%) cases and 1 (0.5%) patient in the OME and 131 non-OME groups, respectively, with a significant P value of 0.046. Perilymph leak 132 was observed in 5 cases from each group, intra-operatively, without statistical 133 significance. Intra-/post-operative portable x-rays confirmed the correct placement of 134 the electrode in all patients. (Table 1 summarizes the intra-operative findings in the 135 cases included in this study). Post-operative complications were also analyzed for 136 both groups. Immediate or early post-operative complications were recorded in 4 137 patients in both groups. Early wound bleeding was observed in 1 (0.6%) patient in the 138 OME group and 2 (1%) in the non-OME group (P value = 0.53). Only 1 patient was 139 taken to the operating room again on the same day for re-exploration from the non- 140 OME group due to a misplaced electrode. All other complications were delayed in 141 nature. One patient (0.5%) in the non-OME group developed a temporary facial nerve 142 palsy on the fifth post-operative day, compared to none of the patients in the OME 143 group (P value = 0.52). Conservative management was successful in this child, with 144 full recovery. With regards to swelling at the wound site, 12 (6.9%) patients in the 145 OME group developed swelling compared to 22 (6%) in the non-OME group. 146 Diagnosis ranged from simple induration at the wound site to seroma or hematoma. 147 These patients were managed accordingly using local antibiotic cream, needle 148 aspiration and pressure bandage or incision and drainage under general anesthesia. 149 Device trauma was considered if there was a history of direct hit to the device with 150 external force either due to a fall, hit by an object or sport trauma; 8 patients (4.6%) in 151 the OME group had a trauma to the device, compared to only 6 (3.6%) in the non- 152 OME group. Wound infection was reported in 3 (1.7%) patients in the OME group 153 and 7 (3.6%) in the non-OME group. Wound dehiscence was only noted in one 154 patient in the OME group. Ear discharge occurred in 5 patients from each group. Six 155 patients were re-implanted in the OME group compared to 2 in the non-OME group. 156 In the OME group, the patients were re-implanted due to device failure. The reason of 157 this failure was not known in 4 of the cases. In one case, the reason was a kinked 158 electrode. The sixth patient had cracked the device after direct trauma. One patient in 159 the non-OME group was re-implanted due to device failure, while the other patient 160 had a misplaced electrode in the internal auditory meatus (IAM). This child was re- 161 explored during the same admission and re-implanted. The difference in post- 162 operative complications between the two groups was not statistically significant. 163 (Table 2 which illustrates the post-operative complications of the study groups). 164 165 Discussion 166 Our study showed that delaying the surgery in children with profound sensorineural 167 hearing loss to treat OME will not add any benefit during surgery. As literature 168 showed, management of OME in preparation for CI surgery is still an area of a 169 debate.4,11,17 Does delaying the implant lead to easier middle ear access and electrode 170 insertion? Additionally, the consequences of postponing the intervention on the 171 development of speech and language can be a major concern.8,14,17 The fear of post- 172 operative complications due to OME is justified.3 However, attributing complications 173 solely to OME has no solid ground. Luntz et al. stated that CI surgery will not 174 increase the incidence or severity of otitis media, in fact, it does quite the 175 opposite.12,13 Antihistamines and intra-nasal corticosteroids were noted to be the 176 treatment of OME.9 Furthermore, VT insertion was recommended in patients with 177 OME who failed medical treatment.4,6,8,11 One study recommended VT insertion 178 around 6 weeks before CI.7 Notably, VT-related problems, such as otorrhea and 179 residual tympanic membrane perforations do exist.18,19,20 We analyzed the 369 cases 180 included in this study, looking into the children who had OME before CI and 181 compared the findings intraoperatively with post-operative surgical outcome. Acute 182 otitis media (AOM) in these children was not included as a parameter in this analysis. 183 As AOM is managed in primary care facilities, it is unusual to see patients with AOM 184 in our institute, therefore we did not include these patients in this study, and it was not 185 noted if patients had AOM previously. 186 187 Inflammation, granulations and hypertrophied mucosa were some of the intra- 188 operative findings noted during CI, not during the clinical assessment. Alzhrani et al. 189 considered children who were found to have granulations or effusion intra-operatively 190 with no findings pre-operatively to be AOM patients.15 In this study, OME was a pre- 191 operative diagnosis. Pre-operative diagnosis was not changed based on intra-operative 192 findings. The diagnosis of OME was based on clinical examination and audiological 193 evaluation by tympanometry. Radiological investigations, such as CT scans, may 194 provide insight into OME as well. If the tympanic membrane cannot be visualized due 195 to wax impaction or a small/narrow canal, the canal will be cleaned and the diagnosis 196 of OME will be based on tympanometry flat curve. A B-curve without OME due to 197 small canals can be noted especially in children who are less than a year old. To 198 overcome this, this study only included those clearly diagnosed with OME clinically 199 and by tympanometry with direct visualization and flat B curve. Dubious cases were 200 excluded. Middle ear inflammation was noted in 2 cases in the OME group, compared 201 to one patient in the non-OME group. Apart from minimal bleeding, no difficulties 202 were noted during CI surgery, either during drilling or in electrode insertion, and 203 finding the round window was not an issue as well. The method of checking electrode 204 placement changed over the period of study. Previously, x-rays were used after 205 surgery to evaluate the position. One case of electrode misplacement led to a change 206 in practice. The current practice is to check the device function intra-operatively via 207 NRT and stapedial reflex test, with x-rays being obtained as well. One study, by 208 Alzoubi et al., reported one case of excessive bleeding and middle ear inflammation 209 during CI in a patient with OME. Despite this, they encouraged medical treatment 210 before CI surgery. This study also concluded that the decision for CI and the timing of 211 surgery should not be delayed to avoid the consequences of delaying the intervention. 212 A follow up did not show any long-term complications.10 The findings from this study 213 support this observation, that CI should not be delayed in fear of serious 214 complications. The patients in this study who had VTs were delayed for at least 7 215 months. Multiple factors played a role in this delay. Firstly, the belief that operating 216 on a patient with OME has increased risk of intra- and post-operative problems. 217 Secondly, surgeons indicated that they wanted to wait until the VT was extruded to 218 avoid the risk of exposing the electrode to the exterior. Furthermore, a limited 219 operating time created a long waiting list for surgery. All of these factors contributed 220 to surgery delay in the patients in this study, but particularly in patients with VTs. 221 None of the VT patients developed any kind of VT-related complications. All of these 222 patients had an intact tympanic membrane before surgery. Notably, we have observed 223 that some patients with OME on the operating table with no previous findings, 224 potentially indicating that spending time on a middle ear effusion issue could be a 225 waste of time. Granulation tissues were encountered during the surgeries with or 226 without inflamed mucosa. Sun et al. reported dealing with pathological granulation 227 tissues due to OME with bleeding in the surgical field, and this was managed using a 228 diamond burr.5 No post-operative complications were reported, even though the 229 patients in that study were below 2 years of age.5 In another study, published by 230 Cevizci et al., 105 of a total of 890 had OME, with only 5 undergoing VT insertion. 231 All of the patients with OME were found to have granulation tissues, edematous 232 middle ear and mastoid mucosa.6 Analysis revealed longer than average operating 233 times, but they did not report any complications attributed to OME after the surgery, 234 concluding that OME diagnosis should not delay the surgery.6 The findings from the 235 current study reflect the findings noted in other studies, such as those by Alzoubi et al. 236 and Cevizci et al. In this study, hypertrophied mucosa and minimal bleeding were 237 observed in 18 and 6 patients in the OME and non-OME groups, respectively. There 238 were no significant differences noted in the post-operative complication rates between 239 the two groups. Five patients from each group developed a perilymph leak during CI, 240 due to inner ear anatomical malformations, similar to those noted by Mondini. In the 241 current study, 3 patients with perilymph gusher had complications post-operatively. 242 Two of these patients were from the non-OME group and one patient was from the 243 OME group. The patient from OME group had dysplastic cochlea with perilymph 244 gusher intra-operatively. This patient presented a few years later with device failure 245 and was re-implanted successfully. One child from the non-OME group presented 246 with a hematoma after a fall with direct trauma to the device. The second patient 247 presented a few months after the surgery with mild wound infection, treated 248 conservatively with local wound care. The presence of OME had no contribution to 249 either gusher or post-operative complications. 250 251 Firstly, this was a retrospective study, limiting the planning and design. Secondly, the 252 decision regarding the OME management pre-operatively was left up to the surgeon’s 253 preference, leading to variations in the standardization of treatment approach. It 254 should be noted, however, that all surgeons agreed on the same treatment duration. 255 Another limitation is the duration of the surgery. As this was a retrospective study 256 retrieving the duration of surgery from old records was a challenge, however, the 257 average recorded surgical time of all cases was 2.5 to 3 hours. Also, we did not 258 analyse the hearing and speech outcome specifically after the surgery as it was not an 259 objective of this paper. 260 261 Conclusion 262 OME is a common pediatric problem that can be found in patients with profound 263 SNHL undergoing CI surgery. Difficulties during CI surgery, such as bleeding and 264 impaired visualization, should not prevent early intervention. The post-operative 265 compilations are not detrimental in patients with OME regardless of prior treatment as 266 revealed in our study and therefore, the presence of OME at the time of surgery 267 should not lead to its delay. We concluded that postponement or vigorous treatment of 268 OME prior to CI is no longer needed since OME does not affect the surgical outcome 269 afterwards. 270 271 Conflicts of interest 272 The authors declare that they have no conflict of interest 273 274 Funding 275 No funding was received for this study. 276 277 Acknowledgement: 278 Authors acknowledge that a preliminary version of the abstract was presented as a 279 poster at the Oman Medical Specialty Board Research Forum 2019/2020 in Muscat, 280 Oman on 7 December 2019 (Oman Medical Specialty Board Research Forum 281 2019/2020: Abstracts. Oman Med J 2019; 34:1–20. 282 From: https://omjournal.org/PDF/Supplement_Abstracts%20%2802J%29_.pdf 283 Authors would like to acknowledge Mr. Sathiya Panchatcharm from department of 284 research and statistics in Oman medical specialty board for his contribution in 285 statistical analysis of data. We would like also to acknowledge the senior cochlear 286 implantation team at Al Nahdha Hospital, Oman. 287 288 Authors Contribution: 289 Al Habsi S contributed via data collection, literature review and data analysis. Al 290 Zaabi K contributed to the work by supervising the first author, review of the data, 291 final literature review and write up of the manuscript. Al Lawati A is the senior author 292 who created the study question, designed and supervised the whole work scheme. 293 294 References: 295 1- Williamson I, Benge S, Barton S, Petrou S, Letley L, Fasey N, et al. Topical 296 intranasal corticosteroids in 4-11 year old children with persistent bilateral 297 otitis media with effusion in primary care: double blind randomised placebo 298 controlled trial. BMJ 2009;339:b4984. https://doi.org/10.1136/bmj.b4984 299 2- Al Zaabi K, Al Lawati A. Delayed Complications of Cochlear Implant 300 Surgical Site: Al Nahdha Hospital 17 Years’ Experience. 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Otol Neurotol 2016; 367 37:1529-34. https://doi.org/10.1097/mao.0000000000001221 368 369 370 371 372 https://doi.org/10.1016/j.otohns.2004.02.011 https://doi.org/10.1080/00016489.2020.1813905 https://doi.org/10.1007/s00431-006-0367-x https://doi.org/10.1177%2F019459989912000401 373 374 Table 1: Comparison of intra-operative findings among the study groups (N=369) 375 Intra-operative finding OME (n = 175) Non-OME (n = 194) Statistical significance (P value) Present Absent Present Absent Middle ear inflammation 2 (1.1%) 173 (98.9%) 1 (0.5%) 193 (99.5%) 0.601 Glue ear 32 (18.3%) 143 (81.7%) 8 (4.1%) 186 (95.9) <0.001 Granulation tissues 1 (0.6%) 174 (99.4%) 2 (1%) 192 (98%) 0.534 Hypertrophied mucosa 18 (10.3%) 157 (89.7%) 0 194 (100%) <0.001 Bleeding 6 (3.4%) 169 (96.6%) 1 (0.5%) 193 (99.5%) <0.046 Perilymph leak 5 (2.9%) 170 (97.1%) 5 (2.6%) 189 (97.4%) 0.551 *% is within OME/non-OME, OME = otitis media with effusion 376 377 Table 2: Comparison of post-operative complications among the study groups (N = 378 369) 379 Post-operative complications Early vs delayed OME (n = 175) (%) Non-OME (n = 194) (%) Statistical significance (P value) Present Absent Present Absent Facial nerve palsy Delayed 0 175 (100%) 1 (0.5%) 193 (99.5%) 0.52 Swelling at wound Delayed 12 (6.9%) 163 (93.1%) 22 (6%) 172 (94%) 0.31 Device trauma Delayed 8 (4.6%) 167 (95.4%) 6 (3.1%) 188 (96.9%) 0.32 Wound infection Delayed 3 (1.7%) 172 (98.3%) 7 (3.6%) 187 (96.4%) 0.21 Bleeding from wound Early 1 (0.6%) 174 (99.4%) 2 (1%) 192 (99%) 0.53 Wound dehiscence Delayed 1 (0.6%) 174 (99.4%) 0 194 (100%) 0.47 Ear discharge Delayed 5 (2.9%) 170 (97.1%) 5 (2.6%) 189 (97.4%) 0.55 Re-exploration Early 0 175 (100%) 1 (0.5%) 193 (99.5%) 0.52 Re- implantation Delayed 6 (3.4%) 169 (96.6%) 2 (2.2%) 192 (99%) 0.111 *% is within OME/non-OME, OME = otitis media with effusion 380