1
|
Mohammadi H, Ebrahimian A, Maftoon N. Experimental Study of Needle Insertion into Gerbil Tympanic Membrane. J Assoc Res Otolaryngol 2024:10.1007/s10162-024-00953-2. [PMID: 38992318 DOI: 10.1007/s10162-024-00953-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 06/12/2024] [Indexed: 07/13/2024] Open
Abstract
The perforation characteristics and fracture-related mechanical properties of the tympanic membrane (TM) greatly affect surgical procedures like myringotomy and tympanostomy performed on the middle ear. We analyzed the most important features of the gerbil TM perforation using an experimental approach that was based on force measurement during a 2-cycle needle insertion/extraction process. Fracture energy, friction energy, strain energy, and hysteresis loss were taken into consideration for the analysis of the different stages of needle insertion and extraction. The results demonstrated that (1) although the TM shows viscoelastic behavior, the contribution of hysteresis loss was negligible compared to other irreversible dissipated energy components (i.e., fracture energy and friction energy). (2) The TM puncture force did not substantially change during the first hours after animal death, but interestingly, it increased after 1 week due to the drying effects of soft tissue. (3) The needle geometry affected the crack length and the most important features of the force-displacement plot for the needle insertion process (puncture force, puncture displacement, and jump-in force) increased with increasing needle diameter, whereas the insertion velocity only changed the puncture and jump-in forces (both increased with increasing insertion velocity) and did not have a noticeable effect on the puncture displacement. (4) The fracture toughness of the gerbil TM was almost independent of the needle geometry and was found to be around 0.33 ± 0.10 kJ/m2.
Collapse
Affiliation(s)
- Hossein Mohammadi
- Department of Systems Design Engineering, University of Waterloo, Waterloo, ON, Canada
- Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, ON, Canada
| | - Arash Ebrahimian
- Department of Systems Design Engineering, University of Waterloo, Waterloo, ON, Canada
- Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, ON, Canada
| | - Nima Maftoon
- Department of Systems Design Engineering, University of Waterloo, Waterloo, ON, Canada.
- Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, ON, Canada.
| |
Collapse
|
2
|
Chen GD, Li L, McCall A, Ding D, Xing Z, Yu YE, Salvi R. Hearing impairment in murine model of Down syndrome. Front Genet 2022; 13:936128. [PMID: 35991545 PMCID: PMC9385999 DOI: 10.3389/fgene.2022.936128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/01/2022] [Indexed: 11/13/2022] Open
Abstract
Hearing impairment is a cardinal feature of Down syndrome (DS), but its clinical manifestations have been attributed to multiple factors. Murine models could provide mechanistic insights on various causes of hearing loss in DS. To investigate mechanisms of hearing loss in DS in the absence of the cadherin 23 mutation, we backcrossed our DS mice, Dp(16)1Yey, onto normal-hearing CBA/J mice and evaluated their auditory function. Body weights of wild type (WT) and DS mice were similar at 3-months of age, but at 9-months, WT weighed 30% more than DS mice. Distortion product otoacoustic emissions (DPOAE), a test of sensory outer hair cell (OHC) function negatively impacted by conductive hearing loss, were reduced in amplitude and sensitivity across all frequencies in DS mice. The middle ear space in DS mice appeared normal with no evidence of infection. MicroCT structural imaging of DS temporal bones revealed a smaller tympanic membrane diameter, oval window, and middle ear space and localized thickening of the bony otic capsule, but no gross abnormalities of the middle ear ossicles. Histological analysis of the cochlear and vestibular sensory epithelium revealed a normal density of cochlear and vestibular hair cells; however, the cochlear basal membrane was approximately 0.6 mm shorter in DS than WT mice so that the total number of hair cells was greater in WT than DS mice. In DS mice, the early and late peaks in the auditory brainstem response (ABR), reflecting neural responses from the cochlear auditory nerve followed by subsequent neural centers in the brainstem, were reduced in amplitude and ABR thresholds were elevated to a similar degree across all frequencies, consistent with a conductive hearing impairment. The latency of the peaks in the ABR waveform were longer in DS than WT mice when compared at the same intensity; however, the latency delays disappeared when the data were compared at the same intensity above thresholds to compensate for the conductive hearing loss. Future studies using wideband tympanometry and absorbance together with detailed histological analysis of the middle ear could illuminate the nature of the conductive hearing impairment in DS mice.
Collapse
Affiliation(s)
- Guang-Di Chen
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, United States
| | - Li Li
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, United States
| | - Andrew McCall
- Optical Imaging and Analysis Facility, School of Dental Medicine, University at Buffalo, Buffalo, NY, United States
| | - Dalian Ding
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, United States
| | - Zhuo Xing
- The Children’s Guild Foundation Down Syndrome Research Program, Genetics and Genomics Program and Department of Cancer Genetics and Genomics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States
- Genetics, Genomics and Bioinformatics Program, University of New York at Buffalo, Buffalo, NY, United States
| | - Y. Eugene Yu
- The Children’s Guild Foundation Down Syndrome Research Program, Genetics and Genomics Program and Department of Cancer Genetics and Genomics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States
- Genetics, Genomics and Bioinformatics Program, University of New York at Buffalo, Buffalo, NY, United States
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, United States
- *Correspondence: Richard Salvi,
| |
Collapse
|
3
|
Improving the Differential Diagnosis of Otitis Media With Effusion Using Wideband Acoustic Immittance. Ear Hear 2021; 42:1183-1194. [PMID: 33928915 DOI: 10.1097/aud.0000000000001037] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The objective of this work is to determine whether there is a systematic effect of middle ear effusion volume on wideband acoustic immittance in children with surgically confirmed otitis media with effusion. DESIGN Wideband acoustic immittance was measured in 49 ears from children (9 months to 11 years) who had a diagnosis of otitis media with effusion and compared to 14 ears from children (10 months to 10 years) without a recent history of otitis media. For children with otitis media with effusion, wideband acoustic immittance testing took place in the child's preoperative waiting room before surgical placement of tympanostomy tubes. Testing was completed in a pressurized condition (wideband tympanometry) for all ears as well as in an ambient condition in a subset of ears. Intraoperative findings regarding effusion volume were reported by the surgeons immediately before tube placement and confirmed following myringotomy. This classified the volume of effusion as compared to middle ear volume categorically as either full, partial, or clear of effusion. The type of wideband acoustic immittance explored in this work was absorbance. Absorbance responses were grouped based on effusion volume into one of four groups: full effusions, partial effusions, ears clear of effusion at the time of surgery, and normal control ears. Standard tympanometry was also completed on all ears. RESULTS Absorbance is systematically reduced as the volume of the middle ear effusion increases. This reduction is present at most frequencies but is greatest in the frequency range from 1 to 5 kHz. A multivariate logistic regression approach was utilized to classify ears based on effusion volume. The regression approach classified ears as effusion present (full and partial ears) or absent (clear ears and normal control ears) with 100% accuracy, ears with effusion present as either partial or full with 100% accuracy, and ears without effusion as either normal control ears or ears clear of effusion with 75% accuracy. Regression performance was also explored when the dataset was split into a training set (70% of the data) and a validation test set (30% of the data) to simulate how this approach would perform on unseen data in a clinical setting. Accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve are reported. Overall, this approach demonstrates high sensitivity and specificity for classifying ears as effusion being present or absent and as present effusions being full or partial with areas under the curve ranging from 1 to 0.944. Despite the lack of effusion present in both clear ears and normal control ears, this approach was able to distinguish between these ears, but with a more moderate sensitivity and specificity. No systematic effect of effusion volume was found on standard tympanometry. CONCLUSIONS Wideband acoustic immittance, and more specifically, absorbance, is a strong and sensitive indicator of the volume of a middle ear effusion in children with otitis media with effusion.
Collapse
|
4
|
Thornton RB, Hakansson A, Hood DW, Nokso-Koivisto J, Preciado D, Riesbeck K, Richmond PC, Su YC, Swords WE, Brockman KL. Panel 7 - Pathogenesis of otitis media - a review of the literature between 2015 and 2019. Int J Pediatr Otorhinolaryngol 2020; 130 Suppl 1:109838. [PMID: 31879085 PMCID: PMC7062565 DOI: 10.1016/j.ijporl.2019.109838] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To perform a comprehensive review of the literature from July 2015 to June 2019 on the pathogenesis of otitis media. Bacteria, viruses and the role of the microbiome as well as the host response are discussed. Directions for future research are also suggested. DATA SOURCES PubMed database of the National Library of Medicine. REVIEW METHODS PubMed was searched for any papers pertaining to OM pathogenesis between July 2015 and June 2019. If in English, abstracts were assessed individually for their relevance and included in the report. Members of the panel drafted the report based on these searches and on new data presented at the 20th International Symposium on Recent Advances in Otitis Media. CONCLUSIONS The main themes that arose in OM pathogenesis were around the need for symptomatic viral infections to develop disease. Different populations potentially having different mechanisms of pathogenesis. Novel bacterial otopathogens are emerging and need to be monitored. Animal models need to continue to be developed and used to understand disease pathogenesis. IMPLICATIONS FOR PRACTICE The findings in the pathogenesis panel have several implications for both research and clinical practice. The most urgent areas appear to be to continue monitoring the emergence of novel otopathogens, and the need to develop prevention and preventative therapies that do not rely on antibiotics and protect against the development of the initial OM episode.
Collapse
Affiliation(s)
- R B Thornton
- Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, Perth, Western Australia, Australia; School of Biomedical Sciences, Faculty Health and Medical Science, University of Western Australia, Perth, Western Australia, Australia
| | - A Hakansson
- Experimental Infection Medicine, Dept. of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - D W Hood
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, OX11 0RD, UK
| | - J Nokso-Koivisto
- Department of Otorhinolaryngology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - D Preciado
- Sheikh Zayed Center for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, USA; Division of Pediatric Otolaryngology, Children's National Health System, Washington, DC, USA
| | - K Riesbeck
- Clinical Microbiology, Dept. of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - P C Richmond
- School of Medicine, Division of Paediatrics, Faculty Health and Medical Science, University of Western Australia, Perth, Western Australia, Australia; Perth Children's Hospital, Perth, Western Australia, Australia
| | - Y C Su
- Clinical Microbiology, Dept. of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - W E Swords
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - K L Brockman
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, USA.
| |
Collapse
|
5
|
Smith KD, Chen T, Gan RZ. Hearing Damage Induced by Blast Overpressure at Mild TBI Level in a Chinchilla Model. Mil Med 2020; 185:248-255. [DOI: 10.1093/milmed/usz309] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Abstract
Introduction
The peripheral auditory system and various structures within the central auditory system are vulnerable to blast injuries, and even blast overpressure is at relatively mild traumatic brain injury (TBI) level. However, the extent of hearing loss in relation to blast number and time course of post-blast is not well understood. This study reports the progressive hearing damage measured in chinchillas after multiple blast exposures at mild TBI levels (103–138 kPa or 15–20 psi).
Materials and Methods
Sixteen animals (two controls) were exposed to two blasts and three blasts, respectively, in two groups with both ears plugged with foam earplugs to prevent the eardrum from rupturing. Auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) were measured in pre- and post-blasts. Immunohistochemical study of chinchilla brains were performed at the end of experiment.
Results
Results show that the ABR threshold and DPOAE level shifts in 2-blast animals were recovered after 7 days. In 3-blast animals, the ABR and DPOAE shifts remained at 26 and 23 dB, respectively after 14 days. Variation of auditory cortex damage between 2-blast and 3-blast was also observed in immunofluorescence images.
Conclusions
This study demonstrates that the number of blasts causing mild TBI critically affects hearing damage.
Collapse
Affiliation(s)
- Kyle D Smith
- School of Aerospace and Mechanical Engineering, University of Oklahoma, 865 Asp Avenue, Norman, OK 73019
| | - Tao Chen
- School of Aerospace and Mechanical Engineering, University of Oklahoma, 865 Asp Avenue, Norman, OK 73019
| | - Rong Z Gan
- School of Aerospace and Mechanical Engineering, University of Oklahoma, 865 Asp Avenue, Norman, OK 73019
| |
Collapse
|
6
|
Stuppert L, Nospes S, Bohnert A, Läßig AK, Limberger A, Rader T. Clinical benefit of wideband-tympanometry: a pediatric audiology clinical study. Eur Arch Otorhinolaryngol 2019; 276:2433-2439. [PMID: 31175454 DOI: 10.1007/s00405-019-05498-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 06/03/2019] [Indexed: 11/24/2022]
Abstract
PURPOSE Wideband-tympanometry (WBT) could give more informative data about the tympanic condition than the conventional tympanometry. In the actual literature, the clinical profit of wideband-tympanometry in pediatric audiological settings is not well evaluated. The aim of this study was to analyze the additional clinical benefit. METHODS 150 children (281 ears) with normal hearing, at the age from 11 days up to 14;10 years, checked with pure tone audiometry or auditory brainstem responses (ABR) participated in this retrospective study. We divided in four age ranges (≤ 6 month; > 6 month ≤ 3 years; > 3 years ≤ 11 years; > 11 years). All children were evaluated with ENT examination including ear microscopy, conventional 226-Hz or 1000-Hz tympanometry and WBT. Ear canal volumes were determined. RESULTS Compared with literature data, our patients aged ≤ 3 years showed smaller mean ear canal volumes (≤ 4 ml). We found a good statistical correlation between the WBT-results and 1000-Hz tympanometry but a rare correlation between WBT-results and ear microscopic findings. In the patients with pathologic ear microscopic results in all groups of age, a significant reduction of WBT-absorbance in 1000 Hz and 2000 Hz was found. CONCLUSIONS This study confirms that WBT collects additive data to detect the correct middle ear status. In pediatric audiology, WBT is an additional useful method to value middle ear problems and to analyze the character of infantile hearing loss. Standard guidelines for the interpretation of the pediatric population are needed. Hence, it will be necessary to determine these findings in a larger number of infantile ears.
Collapse
Affiliation(s)
- Laura Stuppert
- Audiological Acoustics Division, Department of Otolaryngology, Head and Neck Surgery, University of Mainz, HNO-Universitätsklinik, Langenbeckstraße 1, 55131, Mainz, Germany.,Department of Acoustics and Audiology, Aalen University of Applied Sciences, Aalen, Germany
| | - Sabine Nospes
- Communication Disorders Division, Department of Otolaryngology, Head and Neck Surgery, University of Mainz, Mainz, Germany
| | - Andrea Bohnert
- Audiological Acoustics Division, Department of Otolaryngology, Head and Neck Surgery, University of Mainz, HNO-Universitätsklinik, Langenbeckstraße 1, 55131, Mainz, Germany.,Communication Disorders Division, Department of Otolaryngology, Head and Neck Surgery, University of Mainz, Mainz, Germany
| | - Anne Katrin Läßig
- Communication Disorders Division, Department of Otolaryngology, Head and Neck Surgery, University of Mainz, Mainz, Germany
| | - Annette Limberger
- Department of Acoustics and Audiology, Aalen University of Applied Sciences, Aalen, Germany
| | - Tobias Rader
- Audiological Acoustics Division, Department of Otolaryngology, Head and Neck Surgery, University of Mainz, HNO-Universitätsklinik, Langenbeckstraße 1, 55131, Mainz, Germany.
| |
Collapse
|