Introduction

Chronic suppurative otitis media (CSOM) is the most commonly occurring disease affecting 6% of the Indian population.¹ CSOM is defined as a chronic inflammatory process involving middle ear cleft which includes epitympanum, mesotympanum, hypotympanum, Eustachian tube, and mastoid air cells.² It is divided into two groups: Safe or tubotympanic type and Unsafe or atticoantral type. It is characterized by chronic ear discharge and non-healing tympanic membrane perforation and conductive deafness. Conservative management is considered as the initial treatment includes aural toilet, dry ear precautions, topical or systemic antibiotics according to culture and sensitivity results. If these measures are ineffective, surgery is necessary to obtain permanent dry ear, tympanic membrane perforation closure with hearing improvement.²

Myringoplasty is a simple closure of tympanic membrane perforation. Cortical mastoidectomy is clearing the mastoid cavity disease and relieves the block in the aditus and antral region thereby mastoid aeration is achieved. Some factors are responsible for the success or failure of ear surgeries. These are categorized into two groups. Non-mastoid factors include the age of the patient, Eustachian tube function, site& size of the perforation, ossicular status, and cochlear reserve and mastoid factors include pneumatization and inflammation of mastoid.³ Graft uptake and hearing improvement depend on mastoid aeration.

Our retrospective study is defined to compare the surgical outcome of CSOM of safe type in patients who underwent myringoplasty alone or with cortical mastoidectomy with myringoplasty by assessing graft uptake and improvement in pure tone audiometry values.

Materials and Methodology

A retrospective study was conducted on 300 patients who attended the Department of Otorhinolaryngology at Chettinad Hospital and Research Institute. Approval from the ethical committee was obtained. All the patients were explained about the study and informed consent was obtained. Patients between the age group of 18-40 years belonging to both sexes, CSOM of tubotympanic type with pure conductive hearing loss were included in the study. Patients with mixed or sensorineural hearing loss, CSOM with cholesteatoma, granulation, and revision surgery were excluded.

Detailed history including symptoms and duration was taken. Clinical examination including general and systemic examination with thorough ENT examination was carried out. The otoscopic examination was done to define the size and site of tympanic membrane perforation, middle ear status, and Tunning fork test was performed. Pure tone audiometry and x-ray mastoid were done.

Patients were divided into 2 equal groups. Group I comprises 150 patients who underwent myringoplasty alone and Group II comprises 150 patients who underwent cortical mastoidectomy with myringoplasty. Myringoplasty was done using temporalis fascia by underlay technique. Both the group was assessed for graft uptake and pure tone audiometry at one month postoperative. Postoperative pure tone audiometry values were compared with preoperative values. The graft uptake rate and improvement in the hearing were calculated and compared with both groups. The following images (obtained with patient consent) Fig 1 and Fig 2 show patients with chronic history of ear discharge and wet ears with large perforation. These were included in group II, Fig 3 shows image of a patient with chronic otitis media having dry perforation and was included in Group I.

Fig 1: Otoendoscopy picture of patient with chronic otitis media with central perforation	Fig 2: Otoendoscopy picture of patient with chronic otitis media with repeated ear discharge
	Fig 3: Otoendoscopy picture of patient with chronic otitis media having dry perforation

Results

The mean age group is 30.627 and standard deviation is 6.8442 (Table 1).

Patients were divided into 2 equal groups. Group I comprises 150 patients (50%) who underwent myringoplasty alone and Group II comprises 150 patients (50%) who underwent cortical mastoidectomy with myringoplasty (Table 2).

Among 300 patients 148 patients (49.3%) were male and 152 patients (50.7%) were female (Table 3) (Figure 1).

Among 300 patients 172 (57.3%) were employed and 128 (42.7%) were unemployed (Table 4).

Out of 300 patients 252 patients (84%) had hard of hearing and remaining 48 patients (16%) had normal hearing (Table 5) (Figure 2).

Out of 300 patients the graft uptake was present in 272 patients (90.7%) and graft uptake was absent in 28 patients (9.3%) (Table 6).

It shows mean for pre PTA and post PTA are 40.829 and 24.565 respectively. And standard deviation for pre PTA and post PTA are 7.9480 and 7.9941 respectively (Table 7).

The above Table represents t(299)=39.249 and the significant value is 0.000 which is less than 0.05 at 95% confidence interval. Therefore, there is significant relationship between Pre PTA and Post PTA (Table 8).

Discussion

Chronic suppurative otitis media of tubotympanic type is a common disease of middle ear cleft involving all age groups. The causes of CSOM include infection, Eustachian tube dysfunction, allergy, and trauma.¹ Paparella et al. suggested otitis media involves different stages in a continuum of events in that active and inactive stages are part of otomastoiditis due to its connection between the middle ear cavity and mastoid air cells.² The definite management is myringoplasty with or without cortical mastoidectomy to eliminate the disease and reconstruction of the hearing mechanism.³ Myringoplasty was first described by Lonis Petit and mastoidectomy was popularized by William House in 1959.⁴

Fig 4: Mastoidectomy being performed intraoperatively	Fig 5: Completed mastoidectomy intraoperatively

Myringoplasty is a repair of the perforation of the tympanic membrane. Cortical mastoidectomy involves the eradication of the source of infection in the mastoid and improves pneumatization although it has a risk of squamous epithelium ingrowth, injury to vital structures like facial nerve and inner ear structure. Aeration of the middle ear and pressure regulation is achieved by the mastoid.⁵ Mastoid will act as infection nidus if there is a failure to relieve the atticoantral block leading to surgical failure.⁶ Fig 4 and Fig 5 show the intraoperative images when mastoidectomy is performed.

Holmquist and Bergstrom's study from 1978 claimed that mastoidectomy increased the likelihood that patients with noncholesteatomatous chronic otitis media would have a successful tympanoplasty.⁷ In study conducted by Methwani et al, Graft uptake was 76.67% in tympanoplasty alone group and 83.33% in tympanoplasty with cortical mastoidectomy group. In the present study, pre- and post-operative pure-tone average was compared and the statistical difference between tympanoplasty group and tympanoplasty combined with cortical mastoidectomy group was statistically significant.⁸

Pandey et al, study showed the difference was significant (P< 0.05). The mean audiological assessment before was 38.12, after was 28.46 and benefit was 9.66 in group I and 38.24, 26.4 and 11.84 respectively in group II. The difference was significant (P< 0.05).⁹

The post-operative hearing gain in Krishnan et al's study from 2002 was 75% in both groups.¹⁰ Similar to this, Balyan et al. (1997) reported no significant differences in graft failure rates or hearing outcomes among 48 patients with CSOM who underwent tympanoplasty with or without mastoidectomy. They also agreed that the surgery had become more difficult and dangerous because of the mastoidectomy.¹¹ A research published in 2003 by Nayak et al. showed a success rate of 100% in mastoidectomy with tympanoplasty and 60% in tympanoplasty of a sample size of 40 patients who were monitored for a period of 20.4 months, indicating that mastoidectomy is a successful procedure.¹²

An analysis of 484 dry, post-infectious, unoperated, noncholesteatomatous TM perforations by McGrew et al. (2004) compared the effects of mastoidectomy with canal wall up to tympanoplasty alone and found that both groups experienced identical perforation closure success rates of 91%.¹³

The utility of tympanoplasty in chronic noncholesteatomatous otitis media without mastoidectomy was similarly supported by Mishiro et al. (2009), with an equivalent rate of graft success and hearing results regardless of the condition of the ear at repair (draining vs. nondraining) or the addition of a mastoidectomy.¹⁴

Tympanic membrane perforation closure was successful in 76% patients who underwent myringoplasty and in 78.3% of the 46 patients who underwent myringoplasty with mastoidectomy, according to a research by Toros et al. (2010). (p > 0.05) The difference in hearing gain between the two groups was not statistically significant.^15,16

Most of the previous studies showed that there is no statically significant benefit in doing cortical mastoidectomy in addition to myringoplasty. But our present study showed cortical mastoidectomy with myringoplasty gives better results when compared to myringoplasty alone.

Post Operative

The patients in both groups were assessed postoperatively for status of graft uptake and for improvement in pure tone audiogram. Results were better in Group II where myringoplasty with cortical mastoidectomy was done. These patients were followed every month for 6 months and once in 3 months. The recurrence of perforation and ear complaints were considerably less in Group II. Fig 6 and Fig 7 show the post operative otoendoscopy images of good graft uptake post mastoidectomy.

Fig 6: Postoperative image  intact neotympanum	Fig 7: Postoperative image of cortical mastoidectomy and myringoplasty

Conclusion

Our retrospective study shows that there is a statically significant difference in results in both groups. The surgical outcome is better in cortical mastoidectomy with myringoplasty. This is with regard to graft uptake rate, improvement in postoperative pure tone audiometry values, and also improved pneumatization of mastoid. Thus, through this study we can conclude that results of cortical mastoidectomy with myringoplasty is better than myringoplasty alone.

Strengths and Limitations

Our study had a good number of participants and we divided them equally into two groups. The results obtained correspond with that of the population. However our study did not include cases of ossicular erosion,or attic perforations or cholesteatoma which would require additional middle ear work like ossiculoplasty, atticotomy, modified radical mastoidectomy etc. So, we can conclude that in cases of chronic suppurative otitis media of tubotympanic type, doing a simple cortical mastoidectomy to improve mastoid aeration along with myringoplasty goes a really long way in benefitting patients and improving the post operative surgical outcome.

Consent

As per international standards or university standards, participants’ written consent has been collected and preserved by the author(s).

Ethical Approval

As per international standards or university standards written ethical approval has been collected and preserved by the author(s).

Competing Interests

Authors have declared that no competing interests exist.

References

1. Baz MR. Effect of cortical mastoidectomy on audiological outcomes in mucosal chronic otitis media. Al-Azhar International Medical Journal. 2020 Mar 1;1(1):258-63.
2. Paparella MM, Abdelhammid MM, Schachern PA, Sahni R, Yoon TH, da Costa SS. Otopathologic correlates of the continuum of otitis media. Annals of Otology, Rhinology & Laryngology. 1990 Jun;99(6_suppl):17-22.
3. Swamy DR, Shankar T, Kumar M. Role of cortical mastoidectomy in myringoplasty: a clinical study. Journal of Evolution of Medical and Dental Sciences. 2016 Jul 11;5(55):3756-60.
4. Martin MS, Raz Y. Mastoid surgery. In: Myers EN (ed) Operative otolaryngology head and neck surgery, Chap 115, 2nd edn. Elsevier, Amsterdam, 2008. pp 1163–1177.
5. Kaur M, Singh B, Verma BS, Kaur G, Kataria G, SinghS Kansal P, Bhatia B. Comparative evaluation between tympanoplasty alone and tympanoplasty combined with cortical mastoidectomy in non cholesteatomatous chronic suppurative otitis media in patients with sclerotic bone. ISOR-JDMS. 2014 Jun;13(6):40-5.
6. Bajaj AR, Sheikh S, Joshi S, Paike B. Benefit of Tympanoplasty with or without Cortical Mastoidectomy in Active Mucosal Otitis Media–A Comparative Study. Bengal Journal of Otolaryngology and Head Neck Surgery. 2019 Apr 30;27(1).
7. Holmquist J, Bergstrom B. The mastoid air cell system in ear surgery. Arch Otolaryngology. 1978;104:127-9.
8. Methwani DA, Deshmukh PT. Comparative study of type I tympanoplasty with or without mastoidectomy in tubotympanic type of chronic suppurative otitis media patients. Journal of Datta Meghe Institute of Medical Sciences University. 2017 Apr 1;12(2):85.
9. Pandey S, Singh D, Singh BP, Sharma P. A comparative study of tympanoplasty with or without mastoidectomy in treatment of chronic suppurative otitis media tubotympanic type. International Journal of Health and Clinical Research. 2020 Nov 30;3(10):132-5.
10. Nagle SK, Jagade MV, Gandhi SR and Pawar PV. Comparative study of outcome of type I tympanoplasty in dry and wet ear. Indian J Otolaryngol Head Neck Surg. April–June 2009; 61:138
11. Krishnan A, Reddy EK, Nalinesha KM, Jagannath PM. Tympanoplasty with or without cortical mastoidectomy-a comparative study. Indian Journal of Otolaryngology and Head and Neck Surgery. 2002; 54(3): 195-198.
12. Nayak DR, Balakrishnan R, Hazarika P, Mathew PT. Role of cortical mastoidectomy in the results of myringoplasty for dry tubotympanic disease. Indian Journal of Otology. 2003; 9:11-5.
13. McGrew BM, Jackson CG, Glasscock ME. Impact of mastoidectomy on simple tympanic membrane perforation. The Laryngoscope. 2004;114(3):506-511.
14. Mishiro Y, Sakagami M, Takahashi Y et al: Long term outcomes after tympanoplasty with or without mastoidectomy for perforation in CSOM. Eur Arch Otorhino Laryngol. 2009 Jun; 266(6):819-22.
15. Gargava A, Verma P, Gupta A, Saxena S. Comparative Study between Tympanoplasty vs. Tympanomastoidectomy for the surgical outcome in tubotympanic Type CSOM. International Journal of Health and Clinical Research. 2021 Jun 16;4(11):179-81.
16. Balyan FR, Celikkanat S, Aslan A, Taibah A, Russo A, Sanna M. Mastoidectomy in non-cholesteatomatous CSOM – is it necessary? Otolaryngol Head and Neck. 1997;117(6):592-5.