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Tomography (Ann Arbor, Mich.) Sep 2022The aim of this research was to assess possible relationships between petrotympanic fissure (PTF) characteristics, malleus position, and temporomandibular joint...
The aim of this research was to assess possible relationships between petrotympanic fissure (PTF) characteristics, malleus position, and temporomandibular joint disorders (TMD). A retrospective study was performed, including patients with TMD. Magnetic resonance imaging (MRI) and cone-beam computed tomography (CBCT) examination were used to evaluate temporomandibular joint (TMJ) disc position and condylar bone changes. Fifty-eight TMJs from twenty-nine patients (23:6 females: males) were assessed. Erosive changes (DDR-disc displacement with a reduction of 6 (24%), DDwR-disc displacement without a reduction of 8 (61.5%) vs. normal disc position 3 (15%), = 0.012) and condyle osteophytes production (DDR 6 (24%), DDwR 9 (69.2%) vs. normal condyle 7 (35%), = 0.012) were more frequent in subjects with disc displacement compared to normal disc position; malleus was closer to PTF in cases with erosive changes (median 2.15 interquartile range: (1.85-2.75) vs. 2.75 (2.25-3.15), = 0.029) as well as those with condylar osteophytosis (2.25 (1.91-2.75) vs. 2.75 (2.33-3.32), = 0.015); the PTF length was higher in cases with condylar osteophytosis compared to those without (4.45 (3.50-4.77) vs. 3.67 (3.34-4.28), = 0.039). The disc position and disc shape were not related to PTF or malleus position. Malleus position and PTF dimensions were not associated with the PTF type. In cases with erosive changes and condylar osteophytosis, malleus was closer to PTF.
Topics: Male; Female; Humans; Malleus; Temporomandibular Joint; Retrospective Studies; Temporomandibular Joint Disorders; Temporomandibular Joint Disc; Tongue Diseases
PubMed: 36287803
DOI: 10.3390/tomography8050204 -
European Annals of Otorhinolaryngology,... Nov 2020To assess the CT scan aspect of cement bridges used to repair incudostapedial joint discontinuity (ISD) and correlate these observations to audiometric data over time.
AIM
To assess the CT scan aspect of cement bridges used to repair incudostapedial joint discontinuity (ISD) and correlate these observations to audiometric data over time.
MATERIAL AND METHODS
A retrospective study in 12 patients with cement rebridging for ISD compared pre- and post-operative pure-tone average thresholds, Hounsfield units (HU), and bridge size and position on postoperative CT scans.
RESULTS
Mean pre- and post-operative air-bone gap (ABG) was 24.5 and 16dB, respectively. HU did not vary over time post-surgery, with no significant correlation between HU and time to postoperative CTnscan up to 24months (p=0.219). However, a "suggestive" correlation was found between postoperative ABG and HU (p=0.004, r=-0.7). High cement density correlated with good functional outcome: HU <500 indicating functional failure and >1000 indicating ABG closure.
CONCLUSION
Immediate cement polymerization quality (high HU) was stable over time and a marker of ossiculoplasty success, correlating with good functional outcome. Particular care should be taken in preparing the cement, and solidification needs to be on dry mucosa-free ossicles.
Topics: Glass Ionomer Cements; Hearing Loss, Conductive; Humans; Incus; Ossicular Prosthesis; Ossicular Replacement; Retrospective Studies; Treatment Outcome; Tympanoplasty
PubMed: 32057698
DOI: 10.1016/j.anorl.2020.01.013 -
Lin Chuang Er Bi Yan Hou Tou Jing Wai... Oct 2023For tympanosclerosis patients with ossicular chain fixation, we use ossicular chain bypass technique and evaluate its long-term effects. From June 2017 to June 2019, 147...
For tympanosclerosis patients with ossicular chain fixation, we use ossicular chain bypass technique and evaluate its long-term effects. From June 2017 to June 2019, 147 patients with tympanosclerosis who underwent middle ear surgery with otoscopy in Yinchuan First People's Hospital were reviewed. The subjects were divided into three groups according to the implemented operation plan, 51 cases in the ossicular chain mobilization group(OCM), 56 cases in the ossicular chain bypass reconstruction group(OCB), and 40 cases in the malleus-incus complex resection reconstruction group(MICR). Through a three-year follow-up, the medium and long-term effects of different operation plans were compared and analyzed. There was no significant difference among the three groups in the incidence of tympanic membrane perforation, delayed facial nerve palsy, and the dispatch and displacement of PORP. The incidence of tympanic membrane retraction pocket or cholesteatoma after operation in OCB group(0) was significantly lower than that in OCM group(11.76%) and MICR group(7.5%)(<0.05). At 12 months after operation, ΔABG of OCB group and MICR group were better than that in the OCM group(<0.05). At 36 months after operation, ΔABG of OCB group was better than that in the OCM group(<0.05), and there was no significant difference between OCB group and MICR group. The audiological performance of patients with epitympanic sclerosis(ETS) at 12, 24 and 36 months after operation was better than that of patients with posterior tympanosclerosis(PTS) and total tympanosclerosis(TTS)(<0.05). Compared with patients undergoing ossicular chain mobilization and malleus-incus complex resection for ossicular chain reconstruction, patients with tympanosclerosis undergoing bypass technique have better and stable hearing prognosis in medium and long term. This technique can effectively prevent the formation of retracted pocket and cholesteatoma in patients with tympanosclerosis after operation.
Topics: Humans; Tympanosclerosis; Ear Ossicles; Ear, Middle; Malleus; Cholesteatoma; Retrospective Studies; Ossicular Prosthesis; Treatment Outcome
PubMed: 37828886
DOI: 10.13201/j.issn.2096-7993.2023.10.010 -
Otolaryngology--head and Neck Surgery :... Jul 2022This study investigates the accuracy of an automated method to rapidly segment relevant temporal bone anatomy from cone beam computed tomography (CT) images....
OBJECTIVE
This study investigates the accuracy of an automated method to rapidly segment relevant temporal bone anatomy from cone beam computed tomography (CT) images. Implementation of this segmentation pipeline has potential to improve surgical safety and decrease operative time by augmenting preoperative planning and interfacing with image-guided robotic surgical systems.
STUDY DESIGN
Descriptive study of predicted segmentations.
SETTING
Academic institution.
METHODS
We have developed a computational pipeline based on the symmetric normalization registration method that predicts segmentations of anatomic structures in temporal bone CT scans using a labeled atlas. To evaluate accuracy, we created a data set by manually labeling relevant anatomic structures (eg, ossicles, labyrinth, facial nerve, external auditory canal, dura) for 16 deidentified high-resolution cone beam temporal bone CT images. Automated segmentations from this pipeline were compared against ground-truth manual segmentations by using modified Hausdorff distances and Dice scores. Runtimes were documented to determine the computational requirements of this method.
RESULTS
Modified Hausdorff distances and Dice scores between predicted and ground-truth labels were as follows: malleus (0.100 ± 0.054 mm; Dice, 0.827 ± 0.068), incus (0.100 ± 0.033 mm; Dice, 0.837 ± 0.068), stapes (0.157 ± 0.048 mm; Dice, 0.358 ± 0.100), labyrinth (0.169 ± 0.100 mm; Dice, 0.838 ± 0.060), and facial nerve (0.522 ± 0.278 mm; Dice, 0.567 ± 0.130). A quad-core 16GB RAM workstation completed this segmentation pipeline in 10 minutes.
CONCLUSIONS
We demonstrated submillimeter accuracy for automated segmentation of temporal bone anatomy when compared against hand-segmented ground truth using our template registration pipeline. This method is not dependent on the training data volume that plagues many complex deep learning models. Favorable runtime and low computational requirements underscore this method's translational potential.
Topics: Ear, Inner; Facial Nerve; Humans; Image Processing, Computer-Assisted; Malleus; Temporal Bone; Tomography, X-Ray Computed
PubMed: 34491849
DOI: 10.1177/01945998211044982 -
Genome Research Mar 2020DNA recovery from ancient human remains has revolutionized our ability to reconstruct the genetic landscape of the past. Ancient DNA research has benefited from the...
DNA recovery from ancient human remains has revolutionized our ability to reconstruct the genetic landscape of the past. Ancient DNA research has benefited from the identification of skeletal elements, such as the cochlear part of the osseous inner ear, that provides optimal contexts for DNA preservation; however, the rich genetic information obtained from the cochlea must be counterbalanced against the loss of morphological information caused by its sampling. Motivated by similarities in developmental processes and histological properties between the cochlea and auditory ossicles, we evaluate the ossicles as an alternative source of ancient DNA. We show that ossicles perform comparably to the cochlea in terms of DNA recovery, finding no substantial reduction in data quantity and minimal differences in data quality across preservation conditions. Ossicles can be sampled from intact skulls or disarticulated petrous bones without damage to surrounding bone, and we argue that they should be used when available to reduce damage to human remains. Our results identify another optimal skeletal element for ancient DNA analysis and add to a growing toolkit of sampling methods that help to better preserve skeletal remains for future research while maximizing the likelihood that ancient DNA analysis will produce useable results.
Topics: Cochlea; DNA, Ancient; Ear Ossicles; Humans; Sequence Analysis, DNA
PubMed: 32098773
DOI: 10.1101/gr.260141.119 -
Frontiers in Endocrinology 2022Intact mineralization of the auditory ossicles - the smallest bones in the body - is essential for sound transmission in the middle ear, while ossicular...
Intact mineralization of the auditory ossicles - the smallest bones in the body - is essential for sound transmission in the middle ear, while ossicular hypomineralization is associated with conductive hearing loss. Here, we performed a high-resolution analysis of the ossicles in vitamin D receptor deficient mice ( ), which are characterized by hypocalcemia and skeletal mineralization defects, and investigated whether local hypomineralization can be prevented by feeding a calcium-rich rescue diet ( ). In mice fed a regular diet ( ), quantitative backscattered electron imaging (qBEI) revealed an increased void volume (porosity, p<0.0001) along with lower mean calcium content (CaMean, p=0.0008) and higher heterogeneity of mineralization (CaWidth, p=0.003) compared to WT mice. Furthermore, a higher osteoid volume per bone volume (OV/BV; p=0.0002) and a higher osteocyte lacunar area (Lc.Ar; p=0.01) were found in histomorphometric analysis in mice. In mice, full rescue of OV/BV and Lc.Ar (both p>0.05 vs. WT) and partial rescue of porosity and CaWidth (p=0.02 and p=0.04 vs. WT) were observed. Compared with mice, a model of X-linked hypophosphatemic rickets, mice showed a lower osteoid volume in the ossicles (p=0.0002), but similar values in the lumbar spine. These results are consistent with later postnatal impairment of mineral homeostasis in mice than in mice, underscoring the importance of intact mineral homeostasis for ossicle mineralization during development. In conclusion, we revealed a distinct phenotype of hypomineralization in the auditory ossicles of mice that can be partially prevented by a rescue diet. Since a positive effect of a calcium-rich diet on ossicular mineralization was demonstrated, our results open new treatment strategies for conductive hearing loss. Future studies should investigate the impact of improved ossicular mineralization on hearing function.
Topics: Animals; Calcium; Ear Ossicles; Hearing Loss, Conductive; Mice; Mice, Knockout; Minerals; Receptors, Calcitriol
PubMed: 35733772
DOI: 10.3389/fendo.2022.901265 -
Journal of Bone and Mineral Research :... Apr 2003Because bone is obviously in some way adapted to the loads falling on it and because fracture is usually the failure of mechanical competence of main clinical... (Review)
Review
Because bone is obviously in some way adapted to the loads falling on it and because fracture is usually the failure of mechanical competence of main clinical importance, it is often thought that bones are adapted to resist fracture. In this perspective, I consider that this may not be the case. Bones may be designed to be very stiff, and therefore highly mineralized, and therefore brittle; they may be adapted to normal loads, but not to the characteristic loads occurring in falls, or may be very poorly designed to stop cracks traveling once they have started. Bones may also potentially fail in completely contrasting modes, and therefore their design has to be a compromise that does not resist either mode completely successfully. The greatly differing fracture incidences in different bones seen in pre-senile adults suggest that safety factors have been adapted, over evolutionary time, to produce the best compromise for a host of different design constraints.
Topics: Adaptation, Physiological; Animals; Biological Evolution; Biomechanical Phenomena; Bone and Bones; Ear Ossicles; Female; Femur; Fractures, Bone; Horses; Humans; Male; Metacarpus; Models, Biological; Radius; Skull
PubMed: 12674319
DOI: 10.1359/jbmr.2003.18.4.591 -
Journal of the Association For Research... Feb 2020The ossicular joints of the middle ear can significantly affect middle-ear function, particularly under conditions such as high-intensity sound pressures or high...
The ossicular joints of the middle ear can significantly affect middle-ear function, particularly under conditions such as high-intensity sound pressures or high quasi-static pressures. Experimental investigations of the mechanical behaviour of the human incudostapedial joint have shown strong non-linearity and asymmetry in tension and compression tests, but some previous finite-element models of the joint have had difficulty replicating such behaviour. In this paper, we present a finite-element model of the joint that can match the asymmetry and non-linearity well without using different model structures or parameters in tension and compression. The model includes some of the detailed structures of the joint seen in histological sections. The material properties are found from the literature when available, but some parameters are calculated by fitting the model to experimental data from tension, compression and relaxation tests. The model can predict the hysteresis loops of loading and unloading curves. A sensitivity analysis for various parameters shows that the geometrical parameters have substantial effects on the joint mechanical behaviour. While the joint capsule affects the tension curve more, the cartilage layers affect the compression curve more.
Topics: Ear Ossicles; Elasticity; Finite Element Analysis; Humans; Models, Biological; Viscosity
PubMed: 31620954
DOI: 10.1007/s10162-019-00736-0 -
Journal of Comparative Physiology. A,... Sep 2020The sheep middle ear has been used in training to prepare physicians to perform surgeries and to test new ways of surgical access. This study aimed to (1) collect... (Comparative Study)
Comparative Study
The sheep middle ear has been used in training to prepare physicians to perform surgeries and to test new ways of surgical access. This study aimed to (1) collect anatomical data and inertial properties of the sheep middle-ear ossicles and (2) explore effects of these features on sound transmission, in comparison to those of the human. Characteristic dimensions and inertial properties of the middle-ear ossicles of White-Alpine sheep (n = 11) were measured from high-resolution micro-CT data, and were assessed in comparison with the corresponding values of the human middle ear. The sheep middle-ear ossicles differed from those of human in several ways: anteroinferior orientation of the malleus handle, relatively small size of the incus with a relatively short distance to the lenticular process, a large area of the articular surfaces at the incudostapedial joint, and a relatively small moment of inertia along the anterior-posterior axis. Analysis in this study suggests that structure and orientation of the middle-ear ossicles in the sheep are conducive to an increase in the hinge-like ossicular-lever-action around the anterior-posterior axis. Considering the substantial anatomical differences, outcomes of middle-ear surgeries would presumably be difficult to assess from experiments using the sheep middle ear.
Topics: Animals; Ear Ossicles; Ear, Middle; Hearing; Humans; Incus; Malleus; Sheep
PubMed: 32564138
DOI: 10.1007/s00359-020-01430-w -
Journal of Visualized Experiments : JoVE Jan 2017In most mammals, auditory ossicles in the middle ear, including the malleus, incus and stapes, are the smallest bones. In mice, a bony structure called the auditory...
In most mammals, auditory ossicles in the middle ear, including the malleus, incus and stapes, are the smallest bones. In mice, a bony structure called the auditory bulla houses the ossicles, whereas the auditory capsule encloses the inner ear, namely the cochlea and semicircular canals. Murine ossicles are essential for hearing and thus of great interest to researchers in the field of otolaryngology, but their metabolism, development, and evolution are highly relevant to other fields. Altered bone metabolism can affect hearing function in adult mice, and various gene-deficient mice show changes in morphogenesis of auditory ossicles in utero. Although murine auditory ossicles are tiny, their manipulation is feasible if one understands their anatomical orientation and 3D structure. Here, we describe how to dissect the auditory bulla and capsule of postnatal mice and then isolate individual ossicles by removing part of the bulla. We also discuss how to embed the bulla and capsule in different orientations to generate paraffin or frozen sections suitable for preparation of longitudinal, horizontal, or frontal sections of the malleus. Finally, we enumerate anatomical differences between mouse and human auditory ossicles. These methods would be useful in analyzing pathological, developmental and evolutionary aspects of auditory ossicles and the middle ear in mice.
Topics: Animals; Ear Ossicles; Incus; Malleus; Mice; Stapes; X-Ray Microtomography
PubMed: 28117786
DOI: 10.3791/55054