**1.8 Main results and observations**

Preoperative hearing threshold levels of patients from the first, the second, and the control subgroup were similar. The difference between patients from the three subgroups was not statistically significant, which means that hearing

#### **Figure 3.**

*Partial deafness treatment groups for cochlear implantation. ENS, electro-natural stimulation; EC, electrical complement; EAS, electrical-acoustic stimulation; ES, electrical stimulation.*

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**Figure 4.**

*Role of Glucocorticoids in Hearing Preservation in Partial Deafness Treatment*

had minimal hearing preservation (**Table 2** and **Figure 5**).

This study is the first study to report the results of two different regimes of steroid administration in human subjects who underwent cochlear implantation in comparison with the control group. As it was said in the previous paragraph, the findings of this study have shown that glucocorticoid therapy not only stabilizes hearing thresholds but also preserves hearing ability in adult patients. The combination of *intravenously* administrated dexamethasone and *orally* administrated prednisone in one scheme of administration seems to be the optimal treatment regimen.

*Mean hearing thresholds of patients with standard steroid therapy (subgroup No 1), patients with prolonged steroid therapy (subgroup No 2), and control patients (subgroup No 3) in the preoperative period, upon activation, and at 1-month, 6-month, 9-month, and 12-month follow-up after CI implantation.*

thresholds in preoperative period of all participants, who were enrolled to the

The deterioration of average hearing thresholds (measured by pure tone audiometry) was observed from the first point of observation—the activation period. A significant difference was observed between two groups: patients from the second subgroup (combined steroid therapy, prednisone + dexamethasone) and the control subgroup. Patients from the second subgroup had better pure tone audiometry (PTA) results considering low frequencies in comparison with the results of patients from the control group. Similar observation was done in 1, 6, 9, and 12 months after activation follow-up periods. The results of the study may be even more a promise and beneficial for patients. The hearing of participants of the study, to whom combined (prolonged) glucocorticoid therapy was administrated, remained stable during all observed follow-up periods (*activation, 1-month, 6-month, 9-month, and 12-month post-activation follow-ups*), and they did not vary significantly (**Figure 4**). The hearing preservation (HP) rate is calculated using hearing preservation formula by comparing hearing threshold in the 12-month postoperative period with the preoperative hearing thresholds. Then the results were divided, according to the hearing preservation (HP) formula, into minimal HP, partial HP, and complete HP according to **Table 2**. The smallest variability of results was observed in the second subgroup (patients to whom prednisone and dexamethasone were administrated) as well as the highest overall HP rate. Patients from the second subgroup (prolonged steroid therapy) and nearly 69% of the patients from the first subgroup had partial or complete hearing preservation. The majority of patients from the control group

*DOI: http://dx.doi.org/10.5772/intechopen.88863*

study, were similar.

**1.9 Final conclusion**

*Role of Glucocorticoids in Hearing Preservation in Partial Deafness Treatment DOI: http://dx.doi.org/10.5772/intechopen.88863*

thresholds in preoperative period of all participants, who were enrolled to the study, were similar.

The deterioration of average hearing thresholds (measured by pure tone audiometry) was observed from the first point of observation—the activation period. A significant difference was observed between two groups: patients from the second subgroup (combined steroid therapy, prednisone + dexamethasone) and the control subgroup. Patients from the second subgroup had better pure tone audiometry (PTA) results considering low frequencies in comparison with the results of patients from the control group. Similar observation was done in 1, 6, 9, and 12 months after activation follow-up periods. The results of the study may be even more a promise and beneficial for patients. The hearing of participants of the study, to whom combined (prolonged) glucocorticoid therapy was administrated, remained stable during all observed follow-up periods (*activation, 1-month, 6-month, 9-month, and 12-month post-activation follow-ups*), and they did not vary significantly (**Figure 4**).

The hearing preservation (HP) rate is calculated using hearing preservation formula by comparing hearing threshold in the 12-month postoperative period with the preoperative hearing thresholds. Then the results were divided, according to the hearing preservation (HP) formula, into minimal HP, partial HP, and complete HP according to **Table 2**. The smallest variability of results was observed in the second subgroup (patients to whom prednisone and dexamethasone were administrated) as well as the highest overall HP rate. Patients from the second subgroup (prolonged steroid therapy) and nearly 69% of the patients from the first subgroup had partial or complete hearing preservation. The majority of patients from the control group had minimal hearing preservation (**Table 2** and **Figure 5**).

### **1.9 Final conclusion**

*The Human Auditory System - Basic Features and Updates on Audiological Diagnosis and Therapy*

In this equation, *PTApre* is the pure tone average measured preoperatively, *PTApost* is the pure tone average measured postoperatively, and *PTAmax* is the maximal sound intensity generated by a standard audiometer, usually 120 dB hearing level (HL), and *HP* is the rate of hearing preservation in percentage [19]. The protocol of this prospective clinical trial was approved by the Bioethics Commission. Patients enrolled to the study suffered from severe-to-profound hearing loss and were classified according to Prof. H. Skarżyński *partial deafness treatment (PDT) classification* into two groups: *partial deafness treatment-electrical* stimulation (PDT-EC) and *partial deafness treatment-electroacoustic* stimulation

Inclusion and exclusion criteria were in accordance with the consensus of the international *HEARRING* group on hearing preservation in cochlear implant. Study eligibility criteria included participants ≥18 years of age with a cochlear duct length

1.Hearing sound levels in the range of 10–120 decibels (dB) and sound

2.Hearing sound levels of 35–120 dB and frequencies of 500–1000 Hz

3.Hearing sound levels of 75–120 dB and frequencies of 2000–8000 Hz [18]

Exclusion criteria included suffering from severe diseases when the steroid treatment could worsen the patient's condition or when there would be a possibility of interaction between medication intake by patients and steroids. Nonparametric tests were used in the study due to discrepancies in the number of participants between all subgroups, small number of participants in the study, and violation of

Preoperative hearing threshold levels of patients from the first, the second, and the control subgroup were similar. The difference between patients from the three subgroups was not statistically significant, which means that hearing

*Partial deafness treatment groups for cochlear implantation. ENS, electro-natural stimulation; EC, electrical* 

*complement; EAS, electrical-acoustic stimulation; ES, electrical stimulation.*

(PDT-EAS) (**Figure 3**) [20, 21].

of ≥27.1 (measured by computer tomography), with:

normal distribution of pure tone audiometry results [18].

frequencies of 125–250 hertz (Hz)

**1.8 Main results and observations**

(1)

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**Figure 3.**

This study is the first study to report the results of two different regimes of steroid administration in human subjects who underwent cochlear implantation in comparison with the control group. As it was said in the previous paragraph, the findings of this study have shown that glucocorticoid therapy not only stabilizes hearing thresholds but also preserves hearing ability in adult patients. The combination of *intravenously* administrated dexamethasone and *orally* administrated prednisone in one scheme of administration seems to be the optimal treatment regimen.

#### **Figure 4.**

*Mean hearing thresholds of patients with standard steroid therapy (subgroup No 1), patients with prolonged steroid therapy (subgroup No 2), and control patients (subgroup No 3) in the preoperative period, upon activation, and at 1-month, 6-month, 9-month, and 12-month follow-up after CI implantation.*


#### **Table 2.**

*Hearing preservation 12 months after CI implantation, according to the type of treatment (data are given as the number of patients (percentage in brackets)*.

#### **Figure 5.**

*Hearing preservation (HP) rate in three subgroups.*

Previously published studies have shown that there have been new directions in the development and use of electrodes and cochlear implant surgery in recent years. Currently, researchers, clinicians, and commercial companies are working on developing modern steroid-eluting electrodes or electrodes with controlled drug delivery. The results of the preliminary study described in this chapter suggested that combined glucocorticoid administration (according to scheme of administration in the second subgroup) is beneficial in preserving and stabilizing hearing thresholds in patients undergoing cochlear implantation surgery. The findings of this study are supported by the results of similar studies [1, 17]. However, the present study adds to the findings of previous studies by having a relatively long follow-up period, of 12 months after activation, with study analysis conducted during six different follow-up periods. According to the results, administration of glucocorticoids (dexamethasone and prednisone or dexamethasone only) to the patients, who suffered from partial deafness and underwent cochlear implantation surgery, may be important in stabilization of hearing thresholds and in protection of hearing. The dispersion of measured values in the second group (the second subgroup) was lesser than in the first and the control group.

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**Author details**

Magdalena B. Skarżyńska1,2,3

Warsaw/Kajetany, Poland

1 Institute of Sensory Organs, Kajetany, Polnad

provided the original work is properly cited.

2 Center of Hearing and Speech Medincus, Kajetany, Poland

\*Address all correspondence to: m.skarzynska@csim.home.pl

3 World Hearing Center, Institute of Physiology and Pathology of Hearing,

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

*Role of Glucocorticoids in Hearing Preservation in Partial Deafness Treatment*

*DOI: http://dx.doi.org/10.5772/intechopen.88863*

*Role of Glucocorticoids in Hearing Preservation in Partial Deafness Treatment DOI: http://dx.doi.org/10.5772/intechopen.88863*
