Effect Of Tensor Tympani Muscle On The Operation Of Hearing Reconstruction

BackgroundThe chronic suppurative otitis media (CSOM) is a common and frequently-occurringdisease in otology, which can cause mild patients hearing loss, and led severely illpatients to have the extracranial complications. Therefore, we should take activetreatments for the chronic suppurative otitis media. With the rapid development of the earmicrosurgery technique, the tympanoplasty can be reconstructed on the ossicularchain,which based on cleaning pathological tissue thoroughly. The hearing can berepaired and recovery by reconstructing the ossicular chain, repairing the perforation oftympanic membrane,and forming the gas middle ear cavity. How to keep and recover ofhearing in maximize, is a major challenge for clinical. Though there are a large number ofclinical studies on it, many experts and scholars find that there are many factors effect onthe hearing of the tympanoplasty, such as, the state of the middle ear cavity, the functionof the eustachian tube,the surgical options,the choice of implant materials, the artificialossicle types and the operation skills of doctors. In recent years, some scholars and ourprevious study found that the tensor tympani muscle and otitis media may be related topostoperative hearing,but few reports on the relationship between the intact of tensortympani muscle and the postoperative hearing in the clincical study.Therefore, the authorintends to study the effect on hearing of those follow-up CSOM patients who underwentopen-mastoidectomy with tympanoplasty, and analyze on the existence of the tensortympani muscle and the impact of hearing. ObjectiveTo observe the patients’ postoperative hearing and the morphology of tympanicmembrane who underwent the operation of open-mastoidectomy with tympanoplasty,then analysis the postoperative recovery of hearing and the morphology of tympanicmembrane when the tensor tympani muscle intact or not, in the purpose of providingreference for the treatment of tensor tympani muscle in the surgery.Methods1. Clinical data Collect clinical data of patients with chronic suppurative otitis media(including cholesteatoma) who underwent the open-mastoidectomy with tympanoplasty inthe First Affiliated Hospital of Zhengzhou University from September2012to August2013.Inclusion criteria:①Operations are completed by the same Surgeons group②Operationmethod was open-mastoidectomy with typeⅠtympanoplasty and artificial auditory ossiclehearing reconstruction③Preoperative and postoperative hearing tests were completedunder the same condition.④Postoperative ear dry, tympanic membrane healed well,eustachian tube function recovered.⑤Follow-up time was6months or more. In thecollected174cases of clinical data,145patients (ear) match afore-mentioned conditionswere included for study. Among them,74were male,71were female; age from18to62years, average age42.3years; duration in April~48years, average18.6years.62caseswere cholesteatoma otitis media (ear),83cases were chronic suppurative otitis media(ear).2. Grouping There were80cases in the tensor tympani muscle intact group,including45cases of PORP group,35cases of TORP group. The Tensor tympani musclerupture group of65cases, including34cases of PORP group,31cases of TORP group.In addition to observation factors, other groups were basically matching.3. Pre-and Postoperative Examination and Surgical Methods: In the period ofpreoperative period, the routine was the following: pure tone audiometry, Tympanometry,Ear endoscopy and temporal bone CT scan. Surgical method was open-mastoidectomywith tympanoplasty. According to the persistence of stapes superstructure, PORP orTORP titanium prosthesis be chosen for hearing reconstruction.4. Follow-Up The patients were followed up for6-12months, undergone ear endoscope examination after1months,3months;6months out-patient recheck pure4. tone audiometry. Among the35cases followed up for more than12months, puretone audiometry was checked again after12months, part of them also examinated withtemporal bone CT scan.Result1. Observation on tympanic membrane morphology after operationAfter1months the morphology of tympanic membrane: there was no significant differencein morphology among two group. Fascia is moist, slightly swollen.After3months the morphology of tympanic membrane: There were65cases in theTensor tympani muscle intact group, the location and shape of tympanic membrane closeto normal, and the anatomic landmarks were clear, but15cases the tympanic membraneinvagination and the sign were not clear.34cases were in tensor tympani muscle rupturegroup.The tympanic membrane grows well and position was close to normal, but31cases were the tympanic membrane retraction, anatomy unclear and had loss of normalmorphology. According to the morphology of tympanic membrane,divided the patients intotwo groups and then compared the result.As a result the value is13.869, P<0.05, sothere was significant difference between the two groups.2. The pure Tone Audiometry of6Months after Operation The group PORP in whichtensor tympani muscle was intact, the postoperative AC value was27.48±10.02dB, ABGvalue was13.57±6.36dB; The group TORP in which Tensor tympani muscle was intact,the postoperative AC value was28.76±7.14dB, ABG value was21.02±5.48dB; The groupPORP in which tensor tympani muscle was rupture, postoperative AC value was32.36±9.34dB, ABG value was25.73±7.44dB,The group TORP in which Tensor tympanimuscle was rupture, postoperative AC value was39.93±5.12dB, ABG value was31.41±6.25dB. According to the tensor tympani muscle which was intact or not and thetype of auditory ossicles, divided the patients into groups and then compared the results.Comparison between two groups by paired t test. It was found that in both PORP groupand TORP group, The patients’ preoperative AC value and ABG value between the twogroups were not statistically different,but the postoperative AC value and ABG value weremarked differences. The P value less than0.05, So there were statistical significance inthe Result. 3. After12months,the follow-up the patient review hearing, acoustic immittance and CT35cases of pure tone audiometry:31cases of hearing were basically stable, in the31cases18patients were the group which tensor tympani muscle intact,13patients werethe group in which tensor tympani muscle rupture. Hearing loss in4cases,1cases wasthe group in which tensor tympani muscle was intact,3cases were the groupwhich tensor tympani muscle rupture.6Cases of CT Review:4cases the chamber of middle ear were filled with gas, in the4cases three were the group which tensor tympani muscle intact, the another one was thegroup which tensor tympani muscle rupture;2cases with middle ear cavity gas poor, wereboth the group which tensor tympani muscle rupture, there was no one in the group inwhich tensor tympani muscle was intac.Conclusion1. The tensor tympani muscle can maintain the morphology and location of thepostoperative tympanic membrane;2. The retain of tensor tympani muscle can improvethe postoperative hearing results of hearing reconstruction. So the handle of tensortympani muscle should be cautious, try to keep the integrity of the tensor tympani muscle.