Fatal complications in a patient with severe multi-space infections in the oral and maxillofacial head and neck regions: A case report

BACKGROUND Odontogenic infection is one of the common infectious diseases in oral and maxillofacial head and neck regions.Clinically,if early odontogenic infections such as acute periapical periodontitis,alveolar abscess,and pericoronitis of wisdom teeth are not treated timely,effectively and correctly,the infected tissue may spread up to the skull and brain,down to the thoracic cavity,abdominal cavity and other areas through the natural potential fascial space in the oral and maxillofacial head and neck.Severe multi-space infections are formed and can eventually lead to life-threatening complications(LTCs),such as intracranial infection,pleural effusion,empyema,sepsis and even death.CASE SUMMARY We report a rare case of death in a 41-year-old man with severe odontogenic multi-space infections in the oral and maxillofacial head and neck regions.One week before admission,due to pain in the right lower posterior teeth,the patient placed a cigarette butt dipped in the pesticide"Miehailin"into the"dental cavity"to relieve the pain.Within a week,the infection gradually spread bilaterally to the floor of the mouth,submandibular space,neck,chest,waist,back,temporal and other areas.The patient had difficulty breathing,swallowing and eating,and was transferred to our hospital as an emergency admission.Following admission,oral and maxillofacial surgeons immediately organized consultations with doctors in otolaryngology,thoracic surgery,general surgery,hematology,anesthesia and the intensive care unit to assist with treatment.The patient was treated with the highest level of antibiotics(vancomycin)and extensive abscess incision and drainage in the oral,maxillofacial,head and neck,chest and back regions.Unfortunately,the patient died of septic shock and multiple organ failure on the third day after admission.CONCLUSION Odontogenic infection can cause serious multi-space infections in the oral and maxillofacial head and neck regions,which can result in multiple LTCs.The management and treatment of LTCs such as multi-space infections should be multidisciplinary led by oral and maxillofacial surgeons.

The application of the strip-shaped cymba conchae orthosis in the nonsurgical correction of complex auricular deformity

Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from 2020 to 2021 for 6 patients who underwent correction using a stripshaped cymba conchae orthosis. The indications, corrective effects, and complications associated with use of the orthosis were analyzed. Results: There were four indications for treatment: cryptotia with helix adhesion;cryptotia with grade I microtia;cryptotia with excessive helix thickness;and auricular deformity beyond the treatment time window(≥6 months). Excellent corrective effects were observed in all 6 patients. Complications occurred in one patient, who recovered after symptomatic treatment. Conclusion: The use of a strip-shaped cymba conchae orthosis alone or combined with a U-shaped helix orthosis presents a feasible approach for correcting complex auricular deformities or deformities beyond the treatment time window in pediatric patients.

Clinical applications of free medial tibial flap with posterior tibial artery for head and neck reconstruction after tumor resection

Tumor resection causes damage in the head and neck which creates problems in swallowing, chewing, articulation, and vision, all of which seriously affect patients' quality of life. In this work, we evaluated the application of a free medial tibial flap in reconstruction of head and neck defects after tumor resection. We discussed the anatomy, surgical technique, and the advantages and disadvantages of the flap. We found several benefits for the flap, such as, it is especially effective for the defects that require thin-layer epithelium to cover or the separated soft tissue defect; a two-team approach can be used because the donor site is far away from the head and neck; and the flap is easy to integrate because of the subcutaneous fat layer of the free medial tibial flap is thin and the flap is soft. Thus, the medial tibial flap could replace the forearm flap for certain applications.

Role of ^(18)F-FDG PET/CT in pre and post treatment evaluation in head and neck carcinoma

Head and neck cancer(HNC) ranks as the 6th most common cancer worldwide, with the vast majority being head and neck squamous cell carcinoma(HNSCC). The majority of patients present with complicated locally advanced disease(typically stage Ⅲ and Ⅳ) requiring multidisciplinary treatment plans with combinations of surgery, radiation therapy and chemotherapy. Tumor staging is critical to decide therapeutic planning. Multiple challenges include accurate tumor localization with precise delineation of tumor volume, cervical lymph node staging, detection of distant metastasis as well as ruling out synchronous second primary tumors. Somepatients present with cervical lymph node metastasis without obvious primary tumors on clinical examination or conventional cross sectional imaging. Treatment planning includes surgery, radiation, chemotherapy or combinations that could significantly alter the anatomy and physiology of this complex head and neck region, making assessment of treatment response and detection of residual/ recurrent tumor very difficult by clinical evaluation and computed tomography(CT) or magnetic resonance imaging(MRI). 18F-2-fluoro-2-deoxyD-glucose positron emission tomography/CT(18F-FDG PET/CT) has been widely used to assess HNC for more than a decade with high diagnostic accuracy especially in detection of initial distant metastasis and evaluation of treatment response. There are some limitations that are unique to PET/CT including artifacts, lower soft tissue contrast and resolution as compared to MRI, false positivity in post-treatment phase due to inflammation and granulation tissues, etc. The aim of this article is to review the roles of PET/CT in both pre and post treatment management of HNSCC including its limitations that radiologists must know. Accurate PET/CT interpretation is the crucial initial step that leads to appropriate tumor staging and treatment planning.

Recent advances in the application of MXenes for neural tissue engineering and regeneration

Transition metal carbides and nitrides(MXenes)are crystal nanomaterials with a number of surface functional groups such as fluorine,hydroxyl,and oxygen,which can be used as carriers for proteins and drugs.MXenes have excellent biocompatibility,electrical conductivity,surface hydrophilicity,mechanical properties and easy surface modification.However,at present,the stability of most MXenes needs to be improved,and more synthesis methods need to be explored.MXenes are good substrates for nerve cell regeneration and nerve reconstruction,which have broad application prospects in the repair of nervous system injury.Regarding the application of MXenes in neuroscience,mainly at the cellular level,the long-term in vivo biosafety and effects also need to be further explored.This review focuses on the progress of using MXenes in nerve regeneration over the last few years;discussing preparation of MXenes and their biocompatibility with different cells as well as the regulation by MXenes of nerve cell regeneration in two-dimensional and three-dimensional environments in vitro.MXenes have great potential in regulating the proliferation,differentiation,and maturation of nerve cells and in promoting regeneration and recovery after nerve injury.In addition,this review also presents the main challenges during optimization processes,such as the preparation of stable MXenes and long-term in vivo biosafety,and further discusses future directions in neural tissue engineering.

Impaired swallowing mechanics of post radiation therapy head and neck cancer patients: A retrospective videofluoroscopic study

AIM: To determine swallowing outcomes and hyolaryngeal mechanics associated with post radiation therapy head and neck cancer(rt HNC) patients using videofluoroscopic swallow studies. METHODS: In this retrospective cohort study, video-fluoroscopic images of rt HNC patients(n = 21) were compared with age and gender matched controls(n = 21). Penetration-aspiration of the bolus and bolus residue were measured as swallowing outcome variables. Timing and displacement measurements of the anterior and posterior muscular slings elevating the hyolaryngeal complex were acquired. Coordinate data of anatomical landmarks mapping the action of the anterior muscles(suprahyoid muscles) and posterior muscles(long pharyngeal muscles) were used to calculate the distance measurements, and slice numbers were used to calculate time intervals. Canonical variate analysis with post-hoc discriminant function analysis was performed on coordinate data to determine multivariate mechanics of swallowing associated with treatment. Pharyngeal constriction ratio(PCR) was also measured to determine if weak pharyngeal constriction is associated with post radiation therapy.RESULTS: The rt HNC group was characterized by poor swallowing outcomes compared to the control group in regards to: Penetration-aspiration scale(P < 0.0001), normalized residue ratio scale(NRRS) for the valleculae(P = 0.002) and NRRS for the piriform sinuses(P = 0.003). Timing and distance measurements of the anterior muscular sling were not significantly different in the two groups, whereas for the PMS time of displacement was abbreviated(P = 0.002) and distance of excursion was reduced(P = 0.02) in the rt HNC group. A canonical variate analysis shows a significant reduction in pharyngeal mechanics in the rt HNC group(P < 0.0001). The PCR was significantly higher in the test group than the control group(P = 0.0001) indicating reduced efficiency in pharyngeal clearance. CONCLUSION: Using videofluoroscopy, this study shows rt HNC patients have worse swallowing outcomes associated with reduced hyolaryngeal mechanics and pharyngeal constriction compared with controls.

Translocation of a fish spike from the pharynx to the thyroid gland:A case report

BACKGROUND A fish spike stuck in the throat is a common ear,nose,and throat(ENT)emergency.However,it is very rare for a fish spike to reach the thyroid tissue through the throat,which is very dangerous and can lead to pharyngeal fistula,cervical abscess,mediastinal abscess,and thyroid abscess.Proper and timely management can help reduce complications,especially in elderly patients.CASE SUMMARY In the case presented here,the causative factor was dentures,but improper management aggravated the condition.In the case presented here,an elderly woman with a history of accidentally swallowing fish bones for 20 d had a sensation of foreign bodies in her throat.Eventually,computed tomography(CT)of the neck showed that the left side of the thyroid gland had a dense shadow in the form of a stripe.CONCLUSION If a fishbone foreign body is not visible during endoscopic examination but the patient has significant symptoms,the surgeon should be aware that the fishbone may be lodged in the thyroid.To avoid a misdiagnosis,ultrasound,CT,and other tests can be used to clarify the diagnosis.T The first step in treating a fish bone in the thyroid gland is to determine the position of the foreign body and the extent of the infection,and to develop a personalized surgical plan for its removal.At the same time,scientific information should be made available to the general public so that people know that if a fish bone is accidentally lodged,they should not force it to be swallowed or be spit out by inducing vomiting,which are incorrect methods and may aggravate the condition or even cause it to migrate outside the cavity,leading to serious complications,as in this reported case.

Therapeutic efficacy of methylprednisolone sodium succinate via diverse administration routes for mid-to high-frequency sudden sensorineural hearing loss

BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use of methylprednisolone sodium succinate(MPSS)via different administration routes,in combination with conventional medications,remains a topic of interest.AIM To compare the therapeutic efficacy of MPSS administered via different routes in combination with conventional drugs for the treatment of mid-to high-frequency SSNHL.METHODS The medical records of 109 patients with mid-to high-frequency SSNHL were analyzed.The patients were divided into three groups based on the route of administration:Group A[intratympanic(IT)injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection],Group B(intravenous injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection),and Group C(single IT injection of MPSS).The intervention effects were compared and analyzed.RESULTS The posttreatment auditory thresholds in Group A(21.23±3.34)were significantly lower than those in Groups B(28.52±3.36)and C(30.23±4.21;P<0.05).Group A also exhibited a significantly greater speech recognition rate(92.23±5.34)than Groups B and C.The disappearance time of tinnitus,time to hearing recovery,and disappearance time of vertigo in Group A were significantly shorter than those in Groups B and C(P<0.05).The total effective rate in Group A(97.56%)was significantly greater than that in Groups B and C(77.14%and 78.79%,χ^(2)=7.898,P=0.019).Moreover,the incidence of adverse reactions in Groups A and C was significantly lower than that in Group B(4.88%,3.03%vs 2.57%,χ^(2)=11.443,P=0.003),and the recurrence rate in Group A was significantly lower than that in Groups B and C(2.44%vs 20.00%vs 21.21%,χ^(2)=7.120,P=0.028).CONCLUSION IT injection of MPSS combined with conventional treatment demonstrates superior efficacy and safety compared to systemic administration via intravenous infusion and a single IT injection of MPSS.This approach effectively improves patients'hearing and reduces the risk of disease recurrence.

The Role of Toll-Like Receptors and Nuclear Factor κB p65 Protein in the Pathogenesis of Otitis Media

The role of Toll-like receptor 4 (TLR4) and nuclear factor κB p65 (NF-κB p65) proteins in the pathogenesis of otitis media is explored. In recent years, the incidence of otitis media has been rising globally, becoming a significant threat to human health. More and more studies have found that Toll-like receptor 4 (TLR4), as a member of the Toll-like receptor family, can promote the generation of inflammatory factors and is closely related to the body’s immune response and inflammatory response. Nuclear factor-κB p65 (NF-κB p65) is a nuclear transcription factor that can interact with various cytokines, growth factors, and apoptotic factors, participating in processes such as oxidative stress, apoptosis, and inflammation in the body [1]. This article elaborates on the structure, function, and signaling pathways of TLR4 and NF-κB p65 proteins in the pathogenesis of otitis media, aiming to provide more precise targets and better therapeutic efficacy for the diagnosis and treatment of otitis media. The role of inflammation in disease.

An Overview and Comparative Evaluation of Head and Neck Cancer Risk Factors in India and Australia

Aim: An overview and comparative evaluation of head and neck cancer risk factors in India and Australia. Method: In this review we included articles with information on head and neck cancer risk factors and its association based on: smoking tobacco, alcohol, smokeless tobacco, betel nut and areca nut chewing, viral infection like HPV, dental hygiene, diet, family history, socioeconomic status, other heavy metals and systemic conditions. Articles with clinical features, diagnosis, treatment and prognosis were excluded. Results: Head and neck cancer in India has different demographic, risk factors, dietary habits, personal and family history. Oral cancer is more common amongst all head and neck squamous cell cancers in males. This is mainly attributed with consumption of a variety of smokeless tobacco, smoking, alcohol, poverty, illiteracy, cultural, advanced stage at presentation;lack of good treatment infrastructure creates main challenge to India as compared to Australia. Conclusion: The knowledge about risk factors for HNC in public health education for general population supports health promotion and tobacco prevention, which is the main aim of the programs started by the government, as head and neck cancers are potentially preventable.

Extended pectoralis major myocutaneous flap in head and neck reconstruction

Although the pectoralis major myocutaneous flap is often used in head and neck reconstruction, the extension of the skin paddle beyond the inferior limits of the muscle has not been well described. We aim to clarify the design and application of this extended flap in head and neck reconstruction. In this retrospective study, consecutive cases of extended pectoralis major myocutaneous flap reconstruction of post-ablative head and neck defects at a single tertiary referral center were included for analysis. In 7 cases an extended pectoralis major flap was utilized, in which the skin paddle was extended beyond the inferior border of the pectoralis major to include the rectus sheath. Skin and soft tissue as well as composite defects of the oral cavity, parotid/temporal region and neck were reconstructed. All flaps healed satisfactorily with no loss of skin viability. The extended pectoralis major myocutaneous flap is robust and has versatile applications for reconstruction of large, high and three dimensionally complex defects in the head and neck region.

Systematic review of animal models of middle ear surgery

Animal models of middle ear surgery help us to explore disease processes and intervention outcomes in a manner not possible in patients. This review begins with an overview of animal models of middle ear surgery which outlines the advantages and limitations of such models. Procedures of interest include myringoplasty/tympanoplasty, mastoidectomy, ossiculoplasty, stapedectomy, and active middle ear implants. The most important issue is how well the model reflects the human response to surgery. Primates are most similar to humans with respect to anatomy; however, such studies are uncommon now due to expense and ethical issues. Conversely, small animals are easily obtained and housed, but experimental findings may not accurately represent what happens in humans. We then present a systematic review of animal models of middle ear surgery. Particular attention is paid to any distinctive anatomical features of the middle ear, the method of accessing the middle ear and the chosen outcomes. These outcomes are classified as either physiological in live animals,(e.g., behavioural or electrophysiological responses), or anatomical in cadaveric animals,(e.g., light or electron microscopy). Evoked physiological measures are limited by the disruption of the evoking air-conducted sound across the manipulated middle ear. The eleven identified species suitable as animal models are mouse, rat, gerbil, chinchilla, guinea pig, rabbit, cat, dog, sheep, pig and primate. Advantages and disadvantages of each species as a middle ear surgical model are outlined, and a suggested framework to aid in choosing a particular model is presented.

The Economics of Reorganizing Otolaryngology Out-Patient Services for COVID-19 Pandemic in Low- and Middle-Income Countries

The Coronavirus 2019 (COVID-19) pandemic has widespread implications for clinical practice of otolaryngologists in clinics and hospitals. With various reports of otolaryngology practitioners catching infection, a profound structural reorganization of ENT services in the clinic is mandatory for protecting both patients and healthcare workers. The present study focused on quantifying the cost involved in reorganizing the otolaryngology out-patient services in a third world country during the ongoing Covid-19 pandemic. Though the pandemic has increased the cost of running of an otolaryngology practice world over, the impact is huge in India as penetration of health insurance/social security is minimal. As out of pocket expenditure forms a significant proportion of healthcare spending by majority in India, any transfer of additional cost incurred because of Covid-19 pandemic to the patient will burn a bigger hole in their pocket.

Dermatofibrosarcoma Protuberans of the Neck: A Case Report

Background: Dermatofibrosarcoma protuberans (DFSP) is rare soft tissue sarcoma but has a locally aggressive nature. Although most cases are of low grade and have a rare metastasis rate, all DFSP variants have a tendency to show local recurrence. Wide excision with negative margins is the treatment of choice. Aim: To report a case of DFSP who presented with an asymptomatic slow growing tumor similar to etiologies such as hypertrophic scars or other benign soft tissue tumors. Case Presentation: A 68-year-old male presented with a large soft tumor located at the left posterior neck. Local excision was done under the preoperative impression of a benign tumor such as lipoma or sebaceous cyst. However the diagnosis of DFSP was made upon histological examination and the patient underwent another surgery to achieve free resection margins under general anesthesia as well as adjuvant radiotherapy. Conclusion: DFSP is a malignant tumor that is diagnosed histopathologically. Due to the low incidence rate, slow-growing nature, and non-alarming initial presentation features, diagnostic delay or even misdiagnosis is not uncommon.

Surgical treatment of pulsatile tinnitus related to the sigmoid sinus

Objective: Tinnitus-a common clinical symptom-can be categorized into pulsatile tinnitus(PT) and non-PT. Among these, PT is usually associated with sigmoid sinus symptoms, such as sigmoid sinus wall defect or diverticulum, for which various surgical treatments are available. We have discussed the clinical efficacy of surgery for sigmoid sinus-associated PT via the transmastoid approach in this study.Methods: We conducted a retrospective review of 4 patients who underwent surgery for sigmoid sinusassociated PT via the transmastoid approach at Nanjing Drum Tower Hospital from January to December2020. Of these, 2 patients had sigmoid sinus wall defect and 2 had sigmoid sinus diverticulum. Postoperative tinnitus grading and surgical efficacy were determined.Results: After surgery, PT dissolved in 3 patients, while tinnitus significantly decreased in 1 patient.During the follow-up period of 12-18 months, none of the 4 patients showed complications related to increased intracranial pressure or venous sinus thrombosis, and tinnitus symptoms disappeared in 3patients without recurrence, although 1 patient occasionally developed tinnitus. Postoperative thin-slice CTA of the temporal bone indicated that the sigmoid sinus bone wall defect or diverticulum was completely repaired with a thick soft tissue coverage.Conclusion: Surgical repair of sigmoid sinus-associated PT via the transmastoid approach deserves clinical promotion as it exhibited better efficiency while being relatively less invasive.

FDG-PET AS A ROUTINE SURVEILLANCE TOOL IN HEAD AND NECK CARCINOMA SIX MONTHS AFTER TREATMENT

Objective To evaluate prospectively the impact of fluorodeoxyglucose-fluorine-18 positron emission tomography (FDG-PET) in the detection of recurrence, second primary cancers, and distant metastases in head and neck squamous cell carcinoma (HNSCC) 6 months after treatment. Methods A total of 41 patients without any clinical element for recurrence, second primary cancer, or distant metastases received a whole-body FDG-PET as a routine surveillance tool 6 months after initial combined curative therapy for HNSCC. Results There were 35 negative PET results and 6 positive. One patient with abnormal FDG-PET did not have recurrent HNSCC (false positive). Five had true positive results: proven recurrence in 2 patients, second primary cancer in 2, and distant metastasis in 1. The sensitivity and specificity of FDG-PET for the diagnosis of HNSCC recurrence, second tumor, and distant metastases were 100% (5/5) and 97.2% (35/36), respectively. The positive predictive value was 83.3% (5/6). The negative predictive value was 100% (35/35). The overall accuracy was 97.6% (40/41). FDG-PET had a therapeutic impact in 5 of 41 patients (12.2%). There was no impact of FDG-PET on management in other 36 patients. Conclusion FDG-PET is useful as primary method for detecting nodal recurrence and distant metastases in HNSCC as well as second cancer in subclinical patients as it had a high effectiveness. But systematic FDG-PET performed at 6 months in patients without any clinical suspicion of local recurrence was scarcely useful.

Autosomal dominant non-syndromic hearing loss caused by a novel mutation in MYO7A:A case report and review of the literature

BACKGROUND Variants in the MYO7A gene commonly result in Usher syndrome,and in rare cases lead to autosomal dominant non-syndromic deafness(DFNA11).Currently,only nine variants have been reported to be responsible for DFNA11 and their clinical phenotypes are not identical.Here we present a novel variant causing DFNA11 identified in a three-generation Chinese family.CASE SUMMARY The proband was a 53-year-old Han male who presented with post-lingual bilateral symmetrical moderate sensorineural hearing loss.We learned from the patient’s medical history collection that multiple family members also had similar hearing loss,generally occurring around the age of 40.Subsequent investigation by high-throughput sequencing identified a novel MYO7A variant.To provide evidence supporting that this variant is responsible for the hearing loss in the studied family,we performed Sanger sequencing on 11 family members and found that the variant co-segregated with the deafness phenotype.In addition,the clinical manifestation of the 11 affected family members was found to be lateonset bilateral slowly progressive hearing loss,inherited in this family in an autosomal dominant manner.None of the affected family members had visual impairment or vestibular symptoms;therefore,we believe that this novel MYO7A variant is responsible for the rare DFNA11 in this family.CONCLUSION We report a novel variant leading to DFNA11 which further enriches the collection of MYO7A variants,and our review of the nine previous variants that have been identified to cause DFNA11 provides a reference for clinical genetic counseling.

Prevalence of allergic rhinitis and associated risk factors in middle school students from Haikou,China

Objective:To identify the prevalence and influencing factors of allergic rhinitis among middle school students in Haikou,and to provide reference for the prevention and treatment of allergic rhinitis among middle school students in Haikou.Methods:The stratified cluster sampling method was adopted to randomly select the middle school students(aged 12-18)from 8 ordinary or vocational middle schools in Xiuying District,Longhua District,Meilan District and Qiongshan District of Haikou as the survey subjects.The self-made questionnaire was used to conduct the survey from April to May in 2022.Results:A total of 2169 valid questionnaires were collected,the effective rate was 86.6%(2169/2479),814(37.5%)male students and 1355(62.5%)female students.The prevalence rate of allergic rhinitis reported by middle school students in Haikou was 39.8%(863/2169),including 599 cases of intermittent allergic rhinitis(69.4%)and 264 cases of persistent allergic rhinitis(30.6%).The January,February,November and December were the periods of high incidence of symptoms each year.The results of multivariate logistic regression analysis showed that:using antibiotics 5 times a year[OR=2.07,95%CI(1.24-3.45),P=0.005],using antibiotics 3-4 times a year[OR=1.77,95%CI(1.23-2.55),P=0.002],family history of allergic rhinitis[OR=3.84,95%CI(2.67-5.54),P<0.001],history of sinusitis[OR=7.77,95%CI(3.22-18.76),P<0.001],damp living environment[OR=2.87,95%CI(2.00-4.13),P<0.001],history of asthma[OR=8.69,95%CI(1.93-39.12),P=0.005],urban residents[OR=1.68,95%CI(1.35-2.09),P<0.001],frequent exposure to dust[OR=1.59,95%CI(1.20-2.12),P=0.001],male[OR=1.35,95%CI(1.10-1.66),P=0.005],furry pet[OR=1.39,95%CI(1.10-1.75),P=0.006],daily sleep time<8 hours[OR=1.30,95%CI(1.07-1.58),P=0.009]were risk factors for allergic rhinitis.Conclusion:The prevalence of allergic rhinitis among middle school students in Haikou was higher than reported in most areas of China.Male,urban residents,antibiotic use,sleeping less than 8 hours a day,feeding furry pets,living in humid environment,frequent exposure to dust,family history of allergic rhinitis,history of sinusitis and history of asthma were risk factors for allergic rhinitis.Family history of allergic rhinitis,sinusitis and asthma were the most significant factors.

Comparison of tragal perichondrium and COOK artificial material in endoscopic type 1 tympanoplasty

Objective:Various materials have been used for tympanic membrane reconstruction in middle ear surgery.This study aimed to evaluate the difference between the tragal perichondrium and COOK arti-ficial material in patients who underwent endoscopic type 1 tympanoplasty.Method:This retrospective study included patients who underwent endoscopic type 1 tympanoplasty from June 2021 to June 2022 at Sir Run Run Shaw Hospital,Zhejiang University School of Medicine.Patients were divided into group A(tragal perichondrium)and group B(COOK artificial material)ac-cording to the material used in the operation.All patients were followed up for 6 months.The differences in age,gender,operation site,disease course,preoperative air-bone gap(ABG),operation time,blood loss,hearing gain,and wound healing rate were compared between the two groups.Results:This study enrolled 197 patients,with 120 patients in group A and 77 patients in group B.There were no significant differences in age,gender,operation site,disease course,or preoperative ABG be-tween groups A and B(p>0.05).Both groups had significant postoperative improvement in hearing(group A:30.98±9.58 dB vs.17.07±9.92 dB,p<0.001;group B:29.75±7.52 dB vs.14.25±9.07 dB,p<0.001).The mean hearing gain in group A and group B was comparable(14.02±11.91 dB vs.15.50±7.05 dB,p=0.609).The wound healing rates of groups A and B were no differences(93.33%vs.87.01%,p=0.133).The patients in group B had a shorter operation duration(72.57±11.32 min vs.61.86±9.27 min,p=0.045)and less blood loss(12.38±3.7 mL vs.8.10±2.43 mL,p=0.004).Conclusions:Tragal perichondrium and COOK artificial material are reliable for functional and anatomical outcomes in endoscopic type 1 tympanoplasty,and COOK artificial material can save operation time and blood loss in surgery compared to the tragal perichondrium.

Nonlinear dynamic response and stability analysis of the stapes reconstruction in human middle ear

Stapes fracture causes hearing loss and instability in the middle ear hearing system(MEHS). The material used in the stapes reconstruction restores stapes, but the effects of the nonlinear material parameters on the stability of the MEHS are still unknown. To address this challenge, the nonlinear dynamic response and stability of the stapes reconstruction are investigated using a multi-degree-of-freedom mechanical model. The material parameters of the implant are tentatively determined by analyzing the natural frequencies of the undamped system. The dynamical properties of the MEHS are characterized under different external excitations. The approximate solution of the MEHS near the resonant frequency is derived through the multiple-time-scale method(MTSM). The results show that the nonlinear stiffness of the material has little influence on the MEHS in the healthy state, but it causes resonant phenomena between the ossicle and the implant in the pathological state.