Introduction
Chronic suppurative otitis media (CSOM) represents one of the most common infections of the ear. It is a worldwide health problem that is still prevalent in the modern antibiotic era.Reference Lee, Auo and Kang1 Chronic suppurative otitis media is characterised by chronic purulent discharge through a perforated tympanic membrane, which is intermittent or persistent, and which can be associated with cholesteatoma.Reference Gopen, Gulya, Minor and Poe2
Tympanoplasty type I, or myringoplasty, is reconstructive surgery limited to tympanic membrane perforation repair. The key objectives of myringoplasty are to restore tympanic membrane integrity and hearing improvement.Reference Maroto, Gutiérrez, Jiménez, Morente, Rodríguez and Benítez3 Fundamental to the successful closure of any perforation is an adequate area of contact between the graft and tympanic membrane remnant. Other factors influencing successful tympanoplasty include perforation location, ear canal geometry and bleeding during surgery, which can affect optimal graft placement. Tympanic membrane graft migration due to natural events taking place in the reconstructed tympanic membrane can explain some in situ failures, and this remains a significant problem.
It can be inferred that any substances which promote rapid and effectual growth could prevent graft migration because of their direct cohesion with the tympanic membrane. There is a constant search for biomaterials that meet certain requirements, including being safe, biocompatible, low in cost and as structurally similar to human tissue as possible.Reference Jung and Park4, Reference Yoo5
Platelet-rich plasma is defined by a portion of the plasma fraction of autologous blood having a platelet concentration above baseline, with the full complement of clotting and growth factors like platelet-derived growth factor, vascular endothelial growth factor and transforming growth factor.Reference Carter, Fylling and Parnell6, Reference Mehta and Watson7 Platelet-rich plasma serves as a growth factor agonist, and has both chemotactic and mitogenic properties.Reference Mehta and Watson7–Reference Gasling, Acil, Springer, Hubert and Wiltfag9 It functions as a tissue sealant and an adhesive, surgical haemostatic agent. Platelet-rich plasma is safe, being biocompatible, and is effective. It accelerates the regeneration of endothelial, epithelial and epidermal layers. It enhances collagen synthesis, angiogenesis and soft tissue healing, and decreases dermal scarring by reversing glucocorticoids that mediate the inhibition of wound healing.Reference Nikolidakis and Jansen10 Platelet-rich plasma can be prepared with ease, with minimal effort, and is available at the point of care.Reference Everts, Brown Mahoney, Hoffmann, Schönberger, Box and van Zundert11
Cases of CSOM with large, total or subtotal perforations of the tympanic membrane are common in our country. Given the encouraging results of platelet-rich plasma in underlay myringoplasty reported in a small number of previous studies, the present study was undertaken to evaluate the efficacy of platelet-rich plasma in underlay tympanoplasty using temporalis fascia.
Materials and methods
Study population and pre-operative evaluation
The present randomised, prospective study was conducted in the Department of Otorhinolaryngology, Pandit Bhagwat Dayal Sharma Post-Graduate Institute of Medical Sciences, Rohtak, India, from January 2014 to February 2015. It included 40 patients of both sexes, aged 16–50 years, who had unilateral or bilateral chronic inactive (mucosal) otitis media with a dry ear over a period of at least 4 weeks. Patients had not used topical or systemic antibiotics, had a good cochlear reserve, and an air–bone gap of more than 25 dB on pure tone audiometry. Patients for whom there was the slightest doubt of cholesteatoma, revision cases and those with sensorineural hearing loss were excluded from study.
All patients underwent a detailed evaluation that involved history-taking, a general physical examination and a complete ENT examination. Tuning fork tests and a pure tone audiogram were conducted to record pre-operative type and degree of hearing loss.
Institutional review board approval was acquired. Informed consent was obtained and available alternative treatment was discussed.
All procedures were conducted under local anaesthesia. Patients were divided randomly into two groups: group 1 patients (n = 20) underwent underlay myringoplasty using a temporalis fascia graft with platelet-rich plasma; group 2 patients (n = 20) underwent underlay myringoplasty using a temporalis fascia graft without platelet-rich plasma.
Platelet-rich plasma acquisition
First, 10 cc of a patient's venous blood was taken into a tube that contained an anti-coagulant to avoid platelet activation and degranulation. Then, centrifugation, involving a ‘soft spin’, separated the blood into three layers. The bottom-most layer comprised red blood cells (55 per cent of total volume), the top-most layer consisted of acellular platelet-poor plasma (40 per cent of total volume) and the intermediate layer contained platelet-rich plasma (5 per cent of total volume) called the ‘buffy coat’.
Using a syringe, platelet-poor plasma, platelet-rich plasma and some red blood cells were transferred into another tube without an anti-coagulant. A second ‘hard spin’ centrifugation was conducted, which was longer and faster. Platelet-rich plasma was allowed to settle at the bottom. The acellular plasma (80 per cent of the volume) found at the top, was removed with a syringe. The platelet-rich plasma was mixed with bovine thrombin and calcium chloride at the time of application, which results in the gelling of this platelet concentrate.
Myringoplasty
During underlay myringoplasty, the graft was advanced under the tympanomeatal flap and the malleus handle to the anterior-most extent of the perforation. The edges of the graft were tucked under the de-epithelised margin of the drum remnant. The platelet-rich plasma was applied, with a tuberculin syringe fitted with a needle, onto the graft, visible through the perforation. Some of the platelet-rich plasma seeped in-between the graft and tympanic membrane remnant. Small pledgets of Gelfoam soaked in platelet-rich plasma were used to overlap the junction of the rim and graft circumferentially. Gelfoam pledgets soaked in antibiotic solution were placed lateral to the tympanic membrane. An umbilical tape coated with framycetin ointment was placed in the external auditory canal.
Statistical analysis
The collected data were statistically analysed using the student's t-test. For qualitative data, the chi-square test was used. Normally distributed data are presented as means and standard deviations. All tests were performed at a 5 per cent level of significance; thus an association was significant if the p-value was less than 0.05.
Results
In group 1, 11 of 20 patients were male (55 per cent) and 9 were female (45 per cent), with age ranging from 16 to 48 years. In group 2, 13 of the 20 patients were male (65 per cent) and 7 were female (35 per cent), with age ranging from 15 to 45 years (Table 1). In both groups, most of the cases showed unilateral ear involvement (Table 2).
Age and sex distribution of CSOM patients
Data represent numbers of patients. CSOM = chronic suppurative otitis media
Ear involvement
Data represent numbers (and percentages) of cases
All the patients had a history of ear discharge. In group 1, 12 patients (60 per cent) complained of ear discharge for 0–3 years, 6 (30 per cent) for 4–6 years and 2 (10 per cent) for 7–8 years. In group 2, 6 patients (30 per cent) complained of ear discharge for 0–3 years, 7 (35 per cent) for 4–6 years and 7 (35 per cent) for 7–8 years (Table 3).
Duration of ear discharge
Data represent numbers (and percentages) of cases
Patients also complained of varying degrees of deafness. In group 1, 20 patients (100 per cent) were affected; in group 2, 11 patients (55 per cent) complained of deafness. The chi-square test value was 4.85 with 2 degrees of freedom. The p-value was 0.08, which was statistically insignificant. In both groups, most of the cases showed unilateral ear involvement. In group 1, 45 per cent of patients had hearing loss in the range of 25–40 dB, with 55 per cent in the range of 41–55 dB. In group 2, 85 per cent of patients had hearing loss in the range of 25–40 dB, with 15 per cent in the range of 41–55 dB (Table 4).
Audiological assessment
Regarding tympanic membrane perforation, in group 1, five patients (25 per cent) had a medium perforation (up to half the size of the tympanic membrane; grade III), whereas nine patients (45 per cent) had a large central perforation (grade IV) and six patients (30 per cent) had a grade V perforation. In group 2, 3 patients (15 per cent) had a subtotal perforation, whereas 5 patients (25 per cent) had a large central perforation and 12 patients (60 per cent) had a grade III perforation (Table 5). The chi-square test value was 5.02, with 2 degrees of freedom. The p-value was 0.081, which was statistically insignificant.
Relationship between perforation size and graft uptake
Data represent numbers (and percentages) of cases
All patients presented themselves for regular follow up. In group 1, discharge was observed in two patients, which resolved following a change of antibiotic, and only one patient had graft rejection. In group 2, discharge was observed in three patients, which resolved with a change of antibiotic. The overall graft take-up rate in group 1 was 95 per cent; in group 2 the graft take-up rate was 85 per cent. The chi-square test value was 4.32, with 1 degree of freedom. The p-value was 0.03, which was statistically significant. In group 1, the graft take-up rate was 100 per cent both for grade III and grade IV perforations, and was 83.33 per cent for grade V perforations. In group 2, the graft take-up rate was 91.6 per cent for grade III perforations, 80 per cent for grade IV perforations and 66.6 per cent for grade V perforations (Table 5).
Hearing levels were assessed at three months. In group 1, the mean pre-operative hearing threshold was 42.13 dB, while the mean post-operative hearing threshold was 23.51 dB, resulting in a mean gain of 18.62 dB. The mean pre-operative air–bone gap was 30.78 dB, while the mean post-operative air–bone gap was 12.16 dB, giving a mean gain of 18.62 dB. Statistical comparison of pre- versus post-operative air–bone gaps revealed a highly significant difference (p < 0.001).
In group 2, the mean pre-operative hearing threshold was 37.64 dB, while the mean post-operative hearing threshold was 24.49 dB, resulting in a mean gain of 13.15 dB. The mean pre-operative air–bone gap was 26.94 dB, while the mean post-operative gap was 13.79 dB, giving a mean gain of 13.15 dB. The chi-square test value was 8.27, with 3 degrees of freedom. The p-value was 0.04 for the gain in hearing threshold (air–bone gap gain) between both groups, which was statistically significant (Table 6).
Overall follow-up results
Data represent numbers (and percentages) of cases
Discussion
At present, autologous temporalis fascia is the material of choice as a graft for tympanoplasty. This is because of its many qualities, such as being rich in collagen fibres and lacking the elastic elements that make the graft easy to handle. In addition, its ease of availability, even in revision surgery, makes it a popular choice for myringoplasty. Since Heerman described its use in 1961, various authors have utilised the temporalis fascia in tympanoplasty.Reference Gulia, Yadav and Khaowas12 Temporalis fascia has been successfully used both in underlay and overlay tympanoplasty methods.Reference Fiorino and Barbieri13
However, temporalis fascia grafts are not immune to problems. The graft has a tendency to ‘pull off’ the malleus handle, and its use can lead to blunting of the anterior sulcus. This is associated with thickening of the tympanic membrane in this area, resulting in partial fixation of the malleus to the anterior canal wall. These problems can, to a certain extent, be solved by placing the graft under the handle of the malleus.Reference Sakagami, Yuasa and Yuasa14
Platelet releasates have been used to treat wounds since 1985. The application of platelet-rich plasma has been documented in many fields, such as dentistry, orthopaedics, and cosmetic and plastic surgery. In otology, the efficacy of platelet-rich plasma has been demonstrated in tympanoplasty procedures.Reference Driver, Hanft, Fylling and Beriou15
Soumekh et al. assessed the efficacy of a platelet releasate in the treatment of chronic, non-healing perforations in 34 chinchillas with bilateral perforations, with 1 treated ear and 1 control ear. After three months, a comparison of both sides suggested that the platelet releasate was not effective.Reference Soumekh, Hom, Levine, Juhn and Antonelli16 Yeo et al. investigated the effect of platelet-derived growth factor-AA on the healing process of tympanic membrane perforation in rats.Reference Yeo, Kim, Suh and Cho17 The results revealed a speeding up of the healing process of the tympanic membrane defect, an improved rate of healing, and fewer atrophic changes in the healed tympanic membrane. This is explained by the fact that platelet-derived growth factor-AA promotes connective tissue growth.Reference Yeo, Kim, Suh and Cho17 Erkilet et al. created a traumatic tympanic membrane perforation in 44 rats, and found that platelet-rich plasma was effective in accelerating tympanic membrane perforation healing.Reference Erkilet, Koyuncu, Atmaca and Yarim18 Farrag et al. studied the effect of platelet-rich plasma and fibrin sealant on facial nerve regeneration in 49 male adult rats, and found platelet-rich plasma be to effective when added to sutures.Reference Farrag, Lehar, Verhaegen, Carson and Byrne19
• Conventional underlay myringoplasty using temporalis fascia with platelet-rich plasma was compared with temporalis fascia graft without platelet-rich plasma
• Platelet-rich plasma is an autologous material and serves as a growth factor agonist
• It has mitogenic, chemotactic, tissue adhesive, haemostatic and tissue ceiling properties
• Platelet-rich plasma thus improves the overall success rate of graft uptake and can substantially decrease graft failure
• Platelet-rich plasma is an immediate surgical haemostatic agent that is biocompatible, safe, effective and improves graft uptake in myringoplasty
Mehmet et al. studied the effect of platelet-rich plasma on the healing of traumatic tympanic membrane perforations.20 After 1 month, 9 out of 14 cases treated with platelet-rich plasma had total closure; in the control group, 4 out of 18 cases had total closure. However, after two months there was no significant difference in the ratio of closure between the study group and control group (p > 0.05).20 Navarrate Alvaro et al. conducted a pilot study on the efficacy of autologous platelet-rich plasma growth factors in tympanoplasty type I procedures; the perforation closed in all three subjects.Reference Navarrete Alvaro, Ortiz, Rodriguez, Boemo, Fuentes and Mateo21 Gopalakrishnan et al. studied the efficacy of autologous platelet-rich plasma during myringoplasty in terms of tympanic membrane perforation closure.Reference Gopalakrishnan, Venkatasamy and Vivekanandamurthy22 Out of 25 cases, 24 had complete tympanic membrane closure and only 1 failure was observed. In contrast, the tympanic membrane perforation failed to close in 5 out of 25 control subjects. The findings suggested that the use of platelet-rich plasma accelerates graft uptake, and thereby the tympanic membrane perforation closure, following myringoplasty.Reference Gopalakrishnan, Venkatasamy and Vivekanandamurthy22 Similar results were observed in the present study.
Platelet-rich plasma accelerates the healing of tympanic membrane perforation following myringoplasty. It prevents graft displacement or shrinkage, especially in wet grafts, with its sealant property. Platelet-rich plasma improves the overall success rate of myringoplasty. Furthermore, it has no noticeable side effects.Reference Carter, Fylling and Parnell6 Given the efficacy of platelet-rich plasma in myringoplasty, as shown here and in larger samples, its use for tympanic membrane perforation repair would result in lower intra-hospital and out-patient costs.Reference Gonshor23
Platelet-rich plasma is a platelet concentrate with enriched growth factors that can be obtained in a cost-effective manner and which is easy to prepare. In a two-step process, whole blood from the patient is first centrifuged to separate the plasma from packed red blood cells, and then centrifuged further to separate platelet-rich plasma from platelet-poor plasma. This concentrate is then activated with the addition of thrombin or calcium chloride, resulting in a gelatinous platelet gel. Potential candidates for treatment with platelet-rich plasma should undergo a pre-treatment haematological evaluation to rule out coagulopathies and platelet function disorders. Anaemic patients and those with thrombocytopenia may be unsuitable candidates for treatment with platelet-rich plasma. Other potential contraindications include haemodynamic instability, severe hypovolaemia, unstable angina, sepsis, and anti-coagulant or fibrinolytic drug therapy.Reference Marx8, Reference Gasling, Acil, Springer, Hubert and Wiltfag9, Reference Gonshor23
Conclusion
Underlay myringoplasty using platelet-rich plasma is a simple, safe, quick and economical procedure conducted under local anaesthesia. It has a good success rate as compared to fascia alone, with minimal or no morbidity, and no complications. Platelet-rich plasma acts as an immediate surgical haemostatic agent that is biocompatible, safe and effective. It improves overall graft uptake rate in myringoplasty by preventing graft shrinkage. Platelet-rich plasma also functions as a tissue sealant, and plays an important role as a host defence mechanism at the wound site, thus improving the survival of the graft, with no adverse effects.
Competing interests
None declared
