Myringoplasty: Impact of Size and Site of Perforation on the Success Rate

Underlay Myringoplasty Versus Overlay Myringoplasty: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Myringoplasty is still the most performed otological surgery. Nevertheless, the underlay vs. overlay approaches have yet to be determined. The purpose of this study is to compare the surgical and audiological outcomes of underlay and overlay myringoplasty in perforated tympanic membrane patients. A systematic review and meta-analysis synthesizing randomized controlled trials (RCTs), which were retrieved by systematically searching of Web of Science, SCOPUS, PubMed, and Google Scholar until January 25th, 2023. RevMan version 5.4 software was used to pooled dichotomous outcomes using the risk ratio (RR) with the corresponding 95% confidence interval (CI). We registered our protocol in PROSPERO with ID: [CRD42023387432]. We included eight RCTs with 656 tympanic perforation membrane patients. Four RCTs had a low risk of overall bias, two had some concerns, and two had a high risk of bias. The underlay technique was significantly associated with a higher surgical success rate (n = 7 RCTs, RR: 1.21 with 95% CI [1.02, 1.43],  P = 0.03) and audiological success rate (n = 4 RCTs, RR: 1.31 with 95% CI [1.18, 1.44], P < 0.00001). This meta-analysis underscores the potential superiority of the underlay technique in managing tympanic membrane perforations, with significant implications for surgical and audiological outcomes. However, more investigations are still necessary to confirm this result.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-04425-6.

Trichloroacetic acid Alloderm™ Myringoplasty as a novel option for tympanic membrane reconstruction in children

PURPOSE

A novel "Modified TCA Alloderm™ Myringoplasty" (TCA myringoplasty) technique for reconstruction of uncomplicated chronic tympanic membrane (TM) perforations is described.

MATERIALS AND METHODS

Descriptive surgical technique for TCA myringoplasty on 12 total patients from 1/1/2020 to 12/31/2020. 3 patients were excluded for incomplete records. Statistical analysis employed Wilcoxon signed-rank tests. Both structural (pre/post visual inspection and tympanogram) and functional (pre/post pure tone average, PTA) outcome measures are reported.

RESULTS

12 total ears were analyzed from 9 patients. Average age at surgery was 6 (range 3-22). Perforation size ranged from 10 to 60 %. Rate of structural success was 100 %. Functionally, postoperative PTA were significantly decreased from preoperative (mdn(range) = 18.44(13.13-24.38) vs mdn(range) = 11.25(6.25-22.50), p = .008). Only one TM required >1 procedure to achieve closure.

CONCLUSIONS

Chronic TM perforations are typically reconstructed via Type I tympanoplasties with temporalis fascia, reserving myringoplasty for favorable perforations (<25 % in size and posterior). Our novel TCA myringoplasty technique has excellent outcomes independent of size and location. We apply a chemical peel concept to a modified myringoplasty technique, obviating incisions and graft harvest. Advantages of Alloderm™ include: 1) a more rigid graft, facilitating manipulation and precise placement; 2) various size and thickness options, especially useful for dimeric tympanic membranes, tympanolysis of adhesions, and bilateral perforations; 3) no donor morbidity and harvest time; 4) autologous tissue preservation. The sole disadvantage of cost is mitigated by reduced operative time and complication management. This study revealed encouraging proof-of-concept preliminary data warranting prospective and sufficiently powered analysis, supporting the technique as a viable alternative to the gold standard.

Influence of the Size and Location of the Perforation on the Anatomical Results of Myringoplasty

INTRODUCTION

Type 1 tympanoplasty (myringoplasty) is the surgical closure of a perforated eardrum. Its purpose is to restore the integrity of the tympanic membrane and to improve hearing in the affected ear. Nowadays, we note the increasing use of cartilage as material for the reconstruction of the tympanic membrane. The main objective of our study is to evaluate the influence of size and perforation site on the results of type 1 tympanoplasties performed in our department.

MATERIALS AND METHODS

 We carried out a retrospective study of a series of myringoplasties spread over a period of four years and five months from January 1, 2017, to May 31, 2021. For every patient, we collected data regarding age, sex, perforation size, location, and closure of the tympanic membrane after myringoplasty. The audiological results for air conduction (AC) and bone conduction (BC), as well as air-bone gap reduction following surgery, were noted. Follow-up audiograms were performed at the following intervals: two months, four months, and eight months postoperatively. The frequencies tested included 250, 500, 1000, 2000, and 4000 Hz. Similarly, the air-bone gap was estimated on the mean of all frequencies. A chi-squared test and Mann-Whitney test were used to compare qualitative and quantitative variables, respectively.

RESULTS

A total of 123 myringoplasties were included in this study. Closure of the tympanic membrane was achieved successfully in 85.7% for one-quadrant-size perforations (24 cases), and in 76.2% for two-quadrant-size perforations (16 cases). When 50-75% of the tympanic membrane was absent at the time of diagnosis, full repairment was achieved in 89.6% of the patients (n = 24), and in 85.0% (n = 34) when the perforation was subtotal. Recurrences have not happened more significantly for one location of the tympanic defect compared to another. Indeed, failures for anterior quadrant perforations were 14 whereas other sites represented 19 cases of non-integrated grafts. The audition was significantly improved from pre-operatively (AC mean of 48.7 dBs with ranges from 24 to 90 dBs) to post-operatively (30.7 dBs AC with ranges from 10-80 dBs) (p = 0,002). The average postoperative audiometric Rinne was 18 dBs with a gain of 15.37 dBs.

DISCUSSION

Patients with bilateral perforations (tubal dysfunction, allergic rhinitis) are more likely to develop recurrences. Thus, the series considering many patients operated on twice has high failure rates. Good compliance with anti-allergic treatment and with hygiene rules (in particular ear sealing) is essential for the closure of anterior perforations.

CONCLUSION

 It seems through our study that there is no correlation between the size and location of the perforation and its postoperative closure. Risk factors such as smoking, anemia, intraoperative bleeding, and gastroesophageal reflux are important and determining in the healing process.

Cartilaginous Myringoplasty: Anatomical and Functional Results

INTRODUCTION

 Myringoplasty remains a topical subject. Our study aims at analyzing the anatomical and functional results of cartilaginous myringoplasty, and also determining the main factors that could influence its results.

MATERIALS AND METHODS

 A retrospective study of 51 cases of tympanic perforations operated at the ENT department of the Hassan II University Hospital of Fez between January 2018 and November 2021. Only the patients with exclusive cartilage myringoplasty were included. The anatomical and functional results of cartilage myringoplasty were evaluated and analyzed according to several variables. The statistical analysis was performed using SPSS Statistics software.

RESULTS

 The average age of our patients was 35, with a sex ratio of 2.45. The perforation was anterior in 58%, posterior in 12%, and central in 30% of the cases. The average pre-operative audiometric air bone gap (ABG) was 29.3 dB. The most commonly used graft was the conchal cartilage in 89% of cases. A complete cicatrization has been noticed in 92%, and at six months after surgery, a complete closure of the ABG has been observed in 43% of cases, a significant hearing improvement with an ABG between 11 and 20 dB in 24%, a hearing recovery with an ABG between 21 and 30 dB in 21%, and an ABG > 30 dB in 12% of the cases. A statically significant relationship (p<0.05) has been found between the functional or anatomical failure of the myringoplasty; the different predictive factors were: the young age (less than 16 years), the inflammatory state of the tympanic cavity, the anterior location, and large size of the perforation.

CONCLUSION

Cartilaginous myringoplasty provides good anatomical and auditory results. The pre-operative predictive factors, such as age, complete and sufficient drying of the ear, the size and location of the perforation, and the size of the used cartilage, should all be considered for a better anatomical and functional outcome.

Dry versus wet temporalis fascia graft in type-I tympanoplasty: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

To conduct a systematic review and meta-analysis of all randomized controlled trials (RCTs) that examined the efficacy of dry versus wet temporalis fascia graft among patients undergoing type-I tympanoplasty.

METHODS

Web of Science, Scopus, PubMed, and CENTRAL databases were screened from inception until July 2022. The Cochrane risk of bias tool was used to assess the quality of included RCTs. The outcomes were summarized as risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI) in a random-effects model.

RESULTS

Eight RCTs with 989 patients (dry group = 514 and wet group = 475) were included. The overall quality was 'low', 'some concerns', and 'high' risk of bias in five, two, and one RCT(s), respectively. There were no significant differences between both groups regarding the surgical success rate (n = 8 RCTs, RR 0.99, 95% CI [0.95, 1.03], p = 0.6), audiological success rate (n = 5 RCTs, RR = 0.93, 95% CI [0.73, 1.13], p = 0.48), mean difference in pure tone average (n = 2 RCTs, MD = 2.73 Hz, 95% CI [- 2.31, 7.77], p = 0.29), and mean difference in graft placement time (n = 3 RCTs, MD = - 2.18 min, 95% CI [- 5.11, 0.76], p = 0.15). However, the mean difference in operative time was significantly lower in favor of the wet compared with the dry temporalis fascia group (n = 2 RCTs, MD = 2.95 min, 95% CI [- 1.80, 4.11], p < 0.001). The surgical success rate was not significantly different between both groups according to the tympanic membrane perforation size and site.

CONCLUSIONS

The type of temporalis fascia graft (dry or wet) did not influence the clinical outcomes of type-I tympanoplasty.

Comparing Myringoplasty to Type I Tympanoplasty in Tympanic Membrane Repair: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare the anatomic success rates of type I tympanoplasty (tympanoplasty) versus myringoplasty. By our definition, tympanoplasty involves entering the middle ear via elevation of a tympanomeatal flap, while myringoplasty involves surgery to the drumhead without middle ear exposure.

DATA SOURCES

PubMed, Scopus, CINAHL, Cochrane.

REVIEW METHODS

To be included, studies must have documented surgical technique, tympanic membrane (TM) perforation size (as % of TM), and success rate using tissue or alloplastic grafts. Exclusion criteria included series with more than 10% of patients with cholesteatoma or middle ear pathology. A meta-analysis of weighted summary proportions under the random effects model was performed, and proportion differences (PD) were calculated. A secondary analysis of hearing outcomes was performed.

RESULTS

Eighty-five studies met inclusion, with a tympanoplasty cohort of n = 7966 and n = 1759 for myringoplasty. For perforations, less than 50% of the TM, the success rate for tympanoplasty and myringoplasty was 90.2% and 91.4%, respectively (PD: 1.2%, p = .19). In perforations greater than 50%, tympanoplasty and myringoplasty success rates were 82.8% and 85.3%, respectively (PD: 2.5%, p = .29). For both procedures, perforations less than 50% of the TM had higher success rates than perforations greater than 50% of the TM (p < .01). Both techniques endorsed significant improvements to air-bone gap (ABG) metrics.

CONCLUSION

Our analysis suggests that the anatomic success rate is similar for tympanoplasty and myringoplasty, regardless of perforation size, and that smaller perforations experience higher success rates in both techniques. ABG outcomes were also similar between procedure techniques.

Is Cartilage a Better Option than Temporalis Fascia for Grafting in Type 1 Tympanoplasty?: An Institutional Study

Chronic suppurative otitis media (CSOM) is one of the important health problems in our country. The present study was conducted to compare Cartilage and Temporalis Fascia as graft material for Type 1 Tympanoplasty for CSOM. The study was conducted to assess hearing outcome as average AB Gap closure respect to age of the patient and size of perforation, to evaluate Graft uptake with both grafting material and with respect to size of perforation and to find the complication rate. Prospective Comparative study was conducted on 60 patients of CSOM divided in two groups and randomly selected for cartilage Typanoplasty and Temporalis Fascia Tympanoplasty. Hearing result are compared pre and post operative. Group 1(cartilage): Average AB Gap closure was 55% for Small CP, 50% for Moderate CP, 40% for Large CP, 38% for Subtotal CP. In Group 2(Temoralis Fascia): Average AB Gap closure was 81% for Small CP, 72% for Moderate CP, 64% for Large CP, 52% for Subtotal CP. In Group 1, 46% and in Group 2, 69% Average closure of AB gap observed at 12 weeks post operatively. The p value for our study was found to be < 0.05, which statistically indicates better hearing outcome with TF graft. Cartilage is an excellent grafting material because of its accessibility, resistance to negative pressure and high graft uptake rate. Temporalis Fascia is easily available with similar thickness to TM. It showed inferior morphological uptake rate compared to cartilage though functional gain was better.

Endoscopic Transcanal Myringoplasty–Smart Myringoplasty for Nex Gen ENT Surgeons: Our Experience

Otolaryngology is one of the branch where endoscopes is being widely used nowadays to perform different surgeries. Ear surgeries are of special interest among the ENT surgeons. It has several advantages compared to the microscopes. 60 patients underwent endoscopic transcanal myringoplasty by the postgraduate residents under direct supervision of same consultants, using temporalis facia graft. The overall success rate in terms of graft uptake was 86.67% and the AB gap closure of < 10 dB in 63.3% of cases and 10-20 dB in 33.3%. Endoscopic myringoplasty was found to be equally effective, less morbid and very cost effective than the microscopic myringoplasty. This was applicable irrespective of the size of the perforation and condition of the middle ear (dry/wet) in our centre.

Multicenter phase III trial of regenerative treatment for chronic tympanic membrane perforation

OBJECTIVE

To evaluate the efficacy and safety of regenerative treatment for tympanic membrane perforation (TMP) using gelatin sponge, basic fibroblast growth factor (bFGF), and fibrin glue.

METHODS

This was a multicenter, non-randomized, single-arm study conducted at tertiary referral centers. Twenty patients with chronic TMP (age 23-78 years, 6 males, 14 females) were registered from three institutions. All treated patients were included in the safety analysis population. The edges of the TMP were disrupted mechanically by myringotomy and several pieces of gelatin sponge immersed in bFGF were placed and fixed with fibrin glue to cover the perforation. The TMP was examined 4 ± 1 weeks later. The protocol was repeated up to four times until closure was complete. The main outcome measures were closure or a decrease in size of the TMP, hearing improvement, and air-bone gap evaluated 16 weeks after the final regenerative procedure (FRP). Adverse events (AEs) were monitored throughout the study.

RESULTS

Total closure of the TMP at 16 weeks was achieved in 15 out of 20 patients (75.0%, 95% confidence interval [CI]: 50.9%-91.3%) and the mean decrease in size was 92.2% (95%CI: 82.9%-100.0%). The ratio of hearing improvement and the air-bone gap at 16 weeks after FRP were 100% (20/20; 95%CI: 83.2%-100%) and 5.3 ± 4.2 dB (p <0.0001), respectively. Thirteen out of 20 patients (65.0%) experienced at least one AE, but no serious AEs occurred.

CONCLUSION

The results indicate that the current regenerative treatment for TMP using gelatin sponge, bFGF, and fibrin glue is safe and effective.

An insight to tympanic membrane perforation pressure through morphometry: A cadaver study

INTRODUCTION

A cadaveric experimental investigation aimed to show the rupture pressure of the tympanic membrane (TM) for otologists to evaluate its tensile strength.

METHODS

Twenty adult ears in 10 fresh frozen whole cadaveric heads (four males, six females) mean age 72.8 (SD 13.8) years (range 40-86) were studied. The tensile strength of the TM was evaluated with bursting pressure of the membrane. The dimensions of the membranes and perforations were measured with digital imaging software.

RESULTS

The mean bursting pressure of the TM was 97.71 (SD 36.20) kPa. The mean area, vertical and horizontal diameters of the TM were 57.46 (16.23) mm², 9.54 (1.27) mm, 7.99 (1.08) mm respectively. The mean area, length and width of the perforations were 0.55 (0.25) mm², 1.37 (0.50) mm, and 0.52 (0.22) mm, respectively. Comparisons of TM dimension, bursting pressure, and perforation size by laterality and gender showed no significant differences. The bursting pressure did not correlate (positively or negatively) with the TM or perforation sizes.

CONCLUSIONS

The TM can rupture during activities such as freediving or scuba diving, potentially leading to serious problems including brain injuries. Studying such events via cadaveric studies and data from case studies is of fundamental importance. The minimum experimental bursting pressures might better be taken into consideration rather than average values as the danger threshold for prevention of TM damage (and complications thereof) by barotrauma.

A Comparative Study of the Efficacy of Fat Plug Myringoplasty and Conventional Myringoplasty in Chronic Suppurative Otitis Media with Small Central Perforation

Chronic Otitis Media (COM) is a major cause of acquired hearing impairment especially in developing countries. Persistent perforations occur either due to improper treatment of recurrent otitis media or infected traumatic perforation. Myringoplasty, repair of the Tympanic membrane using autologous temporalis fascia, is the standard procedure for COM. Other graft materials commonly used include tragal perichondrium, tragal cartilage and adipose tissue. This prospective study aims to compare the surgical and audiological outcome of fat plug myringoplasty [FPM] and conventional myringoplasty using temporalis fascia [CM-TF] in COM with small dry central perforation. A total of 60 patients of COM with small dry central perforation, aged 16-60 years, during the study period of October 2013 to August 2015 were divided into two groups of 30 cases each. The first group underwent FPM while the second group underwent CM-TF. The graft uptake and hearing outcome [pre operative and 3 months post operative PTA] were assessed. The surgical outcome of FPM with graft uptake of 86.7% was comparable to CM-TF with a graft uptake of 90%. The mean post operative hearing gain in FPM was 3.43 ± 2.81 dB which correlated well with that of CM-TF with 3.85 ± 3.05 dB. The duration of hospital stay and operative time was significantly lower in FPM group. FPM can be safely performed in cases with dry, small central perforations of the tympanic membrane with outcomes comparable to CM-TF.

Evaluating short and long term outcomes following pediatric Myringoplasty with Gelfoam graft for tympanic membrane perforation following ventilation tube insertion

Background

Myringotomy with ventilation tube (VT) insertion to treat recurrent acute otitis media and chronic secretory otitis media has become one of the most common surgical procedures performed in children. Although contemporary literature has detailed the various patient and perioperative factors that affect successful pediatric myringoplasty, there is still limited evidence surrounding the increasing number of graft material options. In particular, gelfoam patching has arisen as a simple and efficient modality for perforation closure, but has a paucity of evidence particularly in pediatric cohorts. Our study aims to evaluate the clinical and audiometric outcomes following gelfoam myringoplasty for TMP following prolonged VT insertion in an urban pediatric population.

Methods

A retrospective review of pediatric patients who underwent myringoplasty between 2013 and 2018 following ventilation tube insertion. Patient demographics, comorbidities, and graft material were correlated with audiometric and clinical outcomes on follow up examination.

Results

One hundred twenty patients underwent myringoplasty, with 61 (50.8%) males with a mean age of 8.9 years old. 101 (84.2%) of patients eventually underwent successful tympanic membrane (TM) closure, with 93 (77.5%) demonstrating closure at initial follow up. In the gelfoam cohort, 77 (90.6%) of patients demonstrated successful TM closure at initial follow up. Overall mean time to closure was 5.6 (standard error (SE) 0.9) months. A multivariate Cox proportional hazards model demonstrated none of the covariates including graft material significantly affected TM closure. Mean change in air conduction threshold were comparable between graft materials.

Conclusions

Pediatric myringoplasty with gelfoam graft material is a safe and viable alternative with favorable short and long term clinical and audiometric outcomes.

Prognostic factors of myringoplasty: study of a 140 cases series and review of the literature

Myringoplasty is one of the most frequent interventions in otology. It aims to restore the eardrum in order to protect against extrinsic contamination by water and to improve hearing. Our study aimed to analyze the factors that may affect anatomical and functional results of myringoplasty or type I tympanoplasty. A retrospective study was performed of a series of 140 cases of myringoplasty over a 6-years period from 2010 to 2015. The approach was post-auricular in 69% of cases and all the patients underwent an underlay technique. Temporal fascia was used in 90.71% of the cases. After an average follow-up of 13 months, the anatomical and functional results were acceptable, with a tympanic closure rate of 88% and an average audiometric gain of 14.22 dB. Several factors affected our results, including the location of the perforation, the active or inactive status of the chronic otitis media, the condition of the opposite ear and the graft material. In light of our results and those of the literature, we believe that the middle ear should be dry at least two months prior to surgery, use of cartilaginous graft material and underlay technique should be preferred and special precautions should be taken in case of anterior or contralateral perforation.

Indian Perspectives on Graft Materials Used for Repair of Tympanic Membrane

INTRODUCTION

Repair of Tympanic Membrane (TM) is one of the most common surgeries performed by the otologists. Literature reveals that Indian surgeons have contributed substantially in the research on techniques and graft materials used for the repair of tympanic membrane, though no review has been written so far highlighting their contributions.

AIM

To summarize and analyse the contributions of Indian authors who have used different graft materials for repair of TM and their studies listed in Medline search.

MATERIALS AND METHODS

A literature review was conducted using a Medline search using keywords of 'myringoplasty' and 'tympanoplasty' with 'India' on 30th June 2016. A total of 243 articles were found listed onwards from year 1998. Out of these 50 articles in which type 1 tympanoplasty or myringoplasty was performed using different graft materials were selected. The content of each abstract was studied in order to identify studies related to topic.

RESULTS

Authors have experimented with a variety of tissues as graft materials. Temporalis Fascia (TF) has been most widely used in 58.6% studies as graft material. The next popular graft is tragal perichondrium. The graft take up rates varied from 68.5% to 100%, while method of reporting of hearing gain in most studies was inconsistent amongst studies, though most studies have reported achievement of serviceable hearing of < 25 dB in most patients.

CONCLUSION

TF was the most prefered material due to anatomic proximity, light material and strength. It was followed in popularity by tragal perichondrium and tragal cartilage. All graft materials have given satisfactory hearing results.

Regenerative treatment for tympanic membrane perforation using gelatin sponge with basic fibroblast growth factor

OBJECTIVE

The objective of this study was to evaluate safety and efficacy of regenerative treatment using gelatin sponge with basic fibroblast growth factor (bFGF) in patients with tympanic membrane perforation (TMP).

METHODS

The current study was a prospective, multicenter, open-label, single-arm, and exploratory clinical trial to evaluate the safety and efficacy of the TM regeneration procedure (TMRP). Myringotomy was used to mechanically disrupt the edge of the TMP, and a gelatin sponge immersed in bFGF was then placed over the perforation. Fibrin glue was dripped over the sponge as a sealant. TMP closure was examined 4 weeks later and, if insufficient, TMRP was repeated a maximum of three more times. TMP closure and hearing improvement 12 weeks after the final TMRP as well as safety were evaluated.

RESULTS

Of the 11 patients with TMP who participated in this study, one who fulfilled the exclusion criteria and did not undergo TMRP and one with cholesteatoma were excluded from the efficacy analysis. TMP closure and hearing improvement 12 weeks after the final TMRP were achieved in eight out of nine patients (88.9%). Mean bone conduction threshold significantly improved 12 weeks after the TMRP compared with baseline (35.7±20.3 vs 29.4±21.0dB, P=0.015). Six out of ten patients receiving TMRP experienced temporary adverse events: appendicitis (serious, severe), otorrhea (mild), otitis media (mild), and sudden hearing loss (mild). However, none were related to the protocol treatment.

CONCLUSION

TMP closure and hearing improvement were frequently confirmed following the TMRPs which were safely performed. These favorable outcomes were accompanied with significant improvement of the bone conduction threshold. These promising outcomes would encourage a large-scaled, randomized and pivotal clinical trial in the future. This trial is registered at http://www.umin.ac.jp/ctr/index.htm (identifier: UMIN000006585).

Effects of Cell-Based Therapy for Treating Tympanic Membrane Perforations in Mice

OBJECTIVE

To investigate the effectiveness of scaffold-embedded mesenchymal stem cells (MSCs) as a topical treatment for healing tympanic membrane perforations (TMPs) in a mouse model.

STUDY DESIGN

Prospective animal study.

SETTING

Experimental.

SUBJECTS AND METHODS

In vitro: under sterile conditions, porcine-derived (Gelita-Spon [GS]), hyaluronate-derived (EpiDisc [ED]), and polyvinyl alcohol (PVA) scaffolds were cut into small pieces and cocultured with murine bone marrow-derived MSCs (BM-MSCs) expressing green fluorescent protein (GFP) for 72 hours. The cultures were either analyzed by confocal microscopy or used for subsequent in vivo experiments. In vivo: 26 mice were divided into 3 groups (ie, control [n = 9], GS [n = 8], ED [n = 9]). Under general anesthesia, TMPs of equal sizes were performed bilaterally using a sterile 27-gauge needle under a surgical microscope. The BM-MSCs embedded within GS or ED scaffolds were soaked in phosphate-buffered saline and then topically applied on right TMPs, and scaffolds alone were applied on left TMPs 6 to 8 hours after injury. Control mice did not receive treatment. On day 7, animals were euthanized and bullae were harvested for histological analysis.

RESULTS

In vitro: BM-MSCs grew well on both GS (P = .0012) and ED (P = .0001) scaffolds compared with PVA. In vivo: 100% of untreated (control) TMPs remained open after 7 days. Animals treated with MSC-embedded ED scaffolds had a higher percentage of TMP closure (P = .016) and a thicker neotympanum (P = .0033) than control animals. The experimentally applied BM-MSCs engrafted and differentiated into epithelial cells suggested by the colocalized expression of cytokeratin-19 and GFP.

CONCLUSIONS

The topical application of bone marrow-derived MSCs enhances the healing of TMPs in this animal model and is a promising alternative to tympanoplasty.