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Animals : An Open Access Journal From... Apr 2023The use of carnivores as experimental models in auditory biology has led to a significant improvement regarding our understanding of the structure and function of the...
The use of carnivores as experimental models in auditory biology has led to a significant improvement regarding our understanding of the structure and function of the ear. Considering that data regarding the anatomy of the middle ear in the red fox are rare, this study aimed to describe the morphological and morphometrical features of the auditory ossicles in the red fox, as well as to provide their shape characteristics by geometric analysis. Nine adult red foxes were used in the study. The malleus, incus and stapes were extracted from the middle ear, prepared, photographed and measured using the software. For the geometric analysis, 19 landmarks were used. Following Principal Component Analysis (PCA), PC1 was found to explain approximately half of all variance (incus: 49.97%; malleus: 49.93%; stapes: 58.49%). The study demonstrated the similar anatomical organization of the auditory ossicles in line with important morphometric and basic geometric data, which can contribute to this field and add a useful perspective to the literature.
PubMed: 37048486
DOI: 10.3390/ani13071230 -
European Archives of... Oct 2023Minimally invasive cochlear implant surgery using a micro-stereotactic surgical targeting system with on-site moulding of the template aims for a reliable, less...
PURPOSE
Minimally invasive cochlear implant surgery using a micro-stereotactic surgical targeting system with on-site moulding of the template aims for a reliable, less experience-dependent access to the inner ear under maximal reduction of trauma to anatomic structures. We present an accuracy evaluation of our system in ex-vivo testing.
METHODS
Eleven drilling experiments were performed on four cadaveric temporal bone specimens. The process involved preoperative imaging after affixing the reference frame to the skull, planning of a safe trajectory preserving relevant anatomical structures, customization of the surgical template, execution of the guided drilling and postoperative imaging for determination of the drilling accuracy. Deviation between the drilled and desired trajectories was measured at different depths.
RESULTS
All drilling experiments were successfully performed. Other than purposely sacrificing the chorda tympani in one experiment, no other relevant anatomy, such as facial nerve, chorda tympani, ossicles or external auditory canal were harmed. Deviation between the desired and achieved path was found to be 0.25 ± 0.16 mm at skulls' surface and 0.51 ± 0.35 mm at the target level. The closest distance of the drilled trajectories' outer circumference to the facial nerve was 0.44 mm.
CONCLUSIONS
We demonstrated the usability for drilling to the middle ear on human cadaveric specimen in a pre-clinical setting. Accuracy proved to be suitable for many applications such as procedures within the field of image-guided neurosurgery. Promising approaches to reach sufficient submillimetre accuracy for CI surgery have been outlined.
Topics: Humans; Surgery, Computer-Assisted; Cochlear Implantation; Temporal Bone; Cochlear Implants; Cadaver
PubMed: 37010602
DOI: 10.1007/s00405-023-07925-x -
European Archives of... Oct 2023Due to smaller bone thickness, young children with conductive or mixed hearing loss or single-sided deafness were previously most commonly treated with a percutaneous...
PURPOSE
Due to smaller bone thickness, young children with conductive or mixed hearing loss or single-sided deafness were previously most commonly treated with a percutaneous osseointegrated bone-anchored hearing aid (BAHA) or an active middle-ear implant. While the BAHA increases the risk of implant infections, skin infection, overgrowth of the screw or involvement of the implant in head trauma, middle-ear implant surgery involves manipulation of the ossicles with possible risk of surgical trauma. These complications can be omitted with transcutaneous bone conduction implant systems like the MED-EL Bonebridge system. The purpose of this study was to analyze whether the second generation of the Bonebridge (BCI 602) that features a decreased implant thickness with a reduced surgical drilling depth can be implanted safely in young children with good postoperative hearing performance.
METHODS
In this study, 14 patients under 12 years were implanted with the second generation of the Bonebridge. Preoperative workup comprised a CT scan, an MRI scan, pure tone audiometry, or alternatively a BERA (bone conduction, air conduction). Since children under 12 years often have a lower bone thickness, the CT was performed to determine the suitability of the temporal bone for optimal implant placement using the Otoplan software.
RESULTS
All patients (including three under the age of five) were successfully implanted and showed a good postoperative hearing performance.
CONCLUSION
With adequate preoperative workup, this device can be safely implanted in children and even children under 5 years of age and allows for an extension of indication criteria toward younger children.
Topics: Humans; Child; Child, Preschool; Hearing Aids; Hearing Loss, Mixed Conductive-Sensorineural; Bone Conduction; Audiometry, Pure-Tone; Ossicular Prosthesis
PubMed: 37000276
DOI: 10.1007/s00405-023-07927-9 -
Medicina (Kaunas, Lithuania) Feb 2023: The persistent stapedial artery (PSA) is a rare congenital vascular malformation involving the middle ear. It is usually associated with pulsatile tinnitus and/or...
: The persistent stapedial artery (PSA) is a rare congenital vascular malformation involving the middle ear. It is usually associated with pulsatile tinnitus and/or conductive hearing loss and can account for multiple risks during middle ear surgery. : we present a case of a 9-year-old male child with conductive hearing loss and persistent stapedial artery in his right ear, who was admitted to our ENT Department for hearing loss. During surgery, we discovered PSA along with congenital stapes agenesis and oval window atresia, as well as an abnormal trajectory of the mastoid segment of the facial nerve. After ossicular reconstruction (transcanal total ossicular replacement prosthesis) with cochleostomy, no surgical complications were recorded and hearing improvement was monitored by pre- and postoperative audiometry. : Stapedial artery is a rare anatomical middle ear abnormality that can prevent proper surgical hearing restoration and can be associated with other simultaneous temporal bone malformations.
Topics: Male; Child; Humans; Stapes; Ossicular Prosthesis; Hearing Loss, Conductive; Ear, Middle; Arteries
PubMed: 36984462
DOI: 10.3390/medicina59030461 -
Medeniyet Medical Journal Mar 2023Pure tone audiometry (PTA) guides surgical decision-making in chronic otitis media (COM), and PTA values depend upon the type and extent of COM.
OBJECTIVE
Pure tone audiometry (PTA) guides surgical decision-making in chronic otitis media (COM), and PTA values depend upon the type and extent of COM.
METHODS
Our cross-sectional study included patients with COM with/without cholesteatoma who were scheduled for surgery. Findings on examination of the middle ear under the microscope and at surgery which could explain the hearing loss were corroborated with preoperative PTA through appropriate statistical methods.
RESULTS
The study included 114 patients (mean age: 31.07 years; range: 7-57). Following preoperative PTA, 50% of patients had moderate hearing loss and ~73% had air-bone gap (ABG) <35 dB. Conductive hearing loss affected 109 patients (97.61%); five had mixed hearing loss. At surgery, 27 patients (23.68%) had ossicular discontinuity, with the incus being the most affected. Twenty-one patients in this group had ABG ≥35 dB. Perforations involving the anterior and posterior halves of the pars tensa, and subtotal perforations, demonstrated the maximum mean hearing loss [45.39±8.29 dB HL (p=0.075), 51.08±12.51 dB HL (p=0.26), respectively]. The mean pure tone average in the intact ossicles group was 43.62±8.07 dB HL and that in the absent/eroded ossicles group was 58.15±11.05 dB HL (p<0.0001); the mean ABG was 27.89±4.77 dB and 38.88±6.47 dB, respectively (p<0.0001).
CONCLUSIONS
Hearing loss was significantly associated with the size but not the site of the central perforation. With ossicular discontinuity, hearing loss and ABG deteriorated significantly. The findings re-establish the relationship between preoperative PTA and the middle ear status which should help surgeons plan surgery and counsel patients regarding hearing outcomes.
PubMed: 36974419
DOI: 10.4274/MMJ.galenos.2023.30509 -
Otology & Neurotology : Official... Jun 2023To test a method to measure the efficacy of active middle ear implants when coupled to the round window.
OBJECTIVE
To test a method to measure the efficacy of active middle ear implants when coupled to the round window.
METHODS
Data previously published in Koka et al. ( Hear Res 2010;263:128-137) were used in this study. Simultaneous measurements of cochlear microphonics (CM) and stapes velocity in response to both acoustic stimulation (forward direction) and round window (RW) stimulation (reverse direction) with an active middle ear implant (AMEI) were made in seven ears in five chinchillas. For each stimulus frequency, the amplitude of the CM was measured separately as a function of intensity (dB SPL or dB mV). Equivalent vibrational input to the cochlea was determined by equating the acoustic and AMEI-generated CM amplitudes for a given intensity. In the condition of equivalent CM amplitude between acoustic and RW stimulation-generated output, we assume that the same vibrational input to the cochlea was present regardless of the route of stimulation.
RESULTS
The measured stapes velocities for equivalent CM output from the two types of input were not significantly different for low and medium frequencies (0.25-4 kHz); however, the velocities for AMEI-RW drive were significantly lower for higher frequencies (4-14 kHz). Thus, for RM stimulation with an AMEI, stapes velocities can underestimate the mechanical input to the cochlea by ~20 dB for frequencies greater than ~4 kHz.
CONCLUSIONS
This study confirms that stapes velocity (with the assumption of equivalent stapes velocity for forward and reverse stimulation) cannot be used as a proxy for effective input to the cochlea when it is stimulated in the reverse direction. Future research on application of intraoperative electrophysiological measurements during surgery (CM, compound action potential, or auditory brainstem response) for estimating efficacy and optimizing device coupling and performance is warranted.
Topics: Humans; Stapes; Ossicular Prosthesis; Round Window, Ear; Cochlea; Acoustic Stimulation; Ear, Middle
PubMed: 36962010
DOI: 10.1097/MAO.0000000000003859 -
Frontiers in Endocrinology 2023Detailed histological analyses are desirable for zebrafish mutants that are models for human skeletal diseases, but traditional histological techniques are limited to...
Detailed histological analyses are desirable for zebrafish mutants that are models for human skeletal diseases, but traditional histological techniques are limited to two-dimensional thin sections with orientations highly dependent on careful sample preparation. On the other hand, techniques that provide three-dimensional (3D) datasets including µCT scanning are typically limited to visualizing the bony skeleton and lack histological resolution. We combined diffusible iodine-based contrast enhancement (DICE) and propagation phase-contrast synchrotron radiation micro-computed tomography (PPC-SRµCT) to image late larval and juvenile zebrafish, obtaining high-quality 3D virtual histology datasets of the mineralized skeleton and surrounding soft tissues. To demonstrate this technique, we used virtual histological thin sections and 3D segmentation to qualitatively and quantitatively compare wild-type zebrafish and mutants to characterize novel soft-tissue phenotypes in the muscles and tendons of the jaw and ligaments of the Weberian apparatus, as well as the sinus perilymphaticus associated with the inner ear. We could observe disrupted fiber organization and tendons of the adductor mandibulae and protractor hyoideus muscles associated with the jaws, and show that despite this, the overall muscle volumes appeared unaffected. Ligaments associated with the malformed Weberian ossicles were mostly absent in mutants, and the sinus perilymphaticus was severely constricted or absent as a result of the fused exoccipital and basioccipital elements. These soft-tissue phenotypes have implications for the physiology of zebrafish, and demonstrate the promise of DICE-PPC-SRµCT for histopathological investigations of bone-associated soft tissues in small-fish skeletal disease models and developmental studies more broadly.
Topics: Animals; Humans; X-Ray Microtomography; Zebrafish; Synchrotrons; Iodine; Radiopharmaceuticals; Skeleton
PubMed: 36950679
DOI: 10.3389/fendo.2023.1108916 -
Otolaryngology--head and Neck Surgery :... Oct 2023Preoperative planning for otologic or neurotologic procedures often requires manual segmentation of relevant structures, which can be tedious and time-consuming....
OBJECTIVE
Preoperative planning for otologic or neurotologic procedures often requires manual segmentation of relevant structures, which can be tedious and time-consuming. Automated methods for segmenting multiple geometrically complex structures can not only streamline preoperative planning but also augment minimally invasive and/or robot-assisted procedures in this space. This study evaluates a state-of-the-art deep learning pipeline for semantic segmentation of temporal bone anatomy.
STUDY DESIGN
A descriptive study of a segmentation network.
SETTING
Academic institution.
METHODS
A total of 15 high-resolution cone-beam temporal bone computed tomography (CT) data sets were included in this study. All images were co-registered, with relevant anatomical structures (eg, ossicles, inner ear, facial nerve, chorda tympani, bony labyrinth) manually segmented. Predicted segmentations from no new U-Net (nnU-Net), an open-source 3-dimensional semantic segmentation neural network, were compared against ground-truth segmentations using modified Hausdorff distances (mHD) and Dice scores.
RESULTS
Fivefold cross-validation with nnU-Net between predicted and ground-truth labels were as follows: malleus (mHD: 0.044 ± 0.024 mm, dice: 0.914 ± 0.035), incus (mHD: 0.051 ± 0.027 mm, dice: 0.916 ± 0.034), stapes (mHD: 0.147 ± 0.113 mm, dice: 0.560 ± 0.106), bony labyrinth (mHD: 0.038 ± 0.031 mm, dice: 0.952 ± 0.017), and facial nerve (mHD: 0.139 ± 0.072 mm, dice: 0.862 ± 0.039). Comparison against atlas-based segmentation propagation showed significantly higher Dice scores for all structures (p < .05).
CONCLUSION
Using an open-source deep learning pipeline, we demonstrate consistently submillimeter accuracy for semantic CT segmentation of temporal bone anatomy compared to hand-segmented labels. This pipeline has the potential to greatly improve preoperative planning workflows for a variety of otologic and neurotologic procedures and augment existing image guidance and robot-assisted systems for the temporal bone.
Topics: Humans; Deep Learning; Ear, Inner; Temporal Bone; Cone-Beam Computed Tomography; Tomography, X-Ray Computed; Image Processing, Computer-Assisted
PubMed: 36883992
DOI: 10.1002/ohn.317 -
Lin Chuang Er Bi Yan Hou Tou Jing Wai... Mar 2023To investigate the etiology, diagnosis and treatment of noninflammatory conductive hearing loss in children. The clinical data of children patients admitted to the Eye &...
To investigate the etiology, diagnosis and treatment of noninflammatory conductive hearing loss in children. The clinical data of children patients admitted to the Eye & ENT Hospital of Fudan University from January 2019 to November 2022 were retrospectively analyzed. A total of 179 cases(189 ears) were analyzed. The main symptoms from high to low were: ear tightness, hearing loss, earache, and facial paralysis. The degree of hearing loss was mild in 34 ears(19.5%), moderate in 70 ears(40.2%), moderate-severe in 52 ears(29.9%), severe in 18 ears(10.3%). The mean hearing threshold of otosclerosis was the highest(63.5±7.8) dB HL, and the mean air-bone gap of ossicular chain malformation was the largest(35.4±9.8) dB HL. The mean hearing threshold of the affected ear was(50.4±14.5) dB HL, and the mean air bone gap was(30.3±10.4) dB HL. After operation, the results were(36.1± 14.5) dB HL and(20.0±8.6) dB HL, respectively. Distribution of surgical methods for ossicular chain reconstruction: 88 ears(46.6%) of TORP, 49 ears(25.9%) of PORP, 8(4.2%) ears of Piston, 9 ears(4.8%) of autogenous ossicular reconstruction, and 35 ears(18.5%) of ossicular chain relaxation. CT diagnostic rate showed more sensitivity to malleus and incus abnormalities, the diagnosis rate of congenital middle ear cholesteatoma was the highest. The mean duration time of diagnosis was(2.2±2.9) years, while the diagnosis of ossicular chain malformation([5.2±4.2]years), otosclerosis([4.4±4.1]years), tympanosclerosis([5.4±0.9]years) took longer. In the diagnosis and treatment of noninflammatory conductive hearing loss in children, the combination of detailed medical history, specialized examination and imaging examination can maximize the accuracy of diagnosis and achieve the purpose of personalized comprehensive treatment. Surgical intervention with appropriate timing is important to remove lesions and improve hearing.
Topics: Humans; Child; Hearing Loss, Conductive; Otosclerosis; Retrospective Studies; Ear, Middle; Ear Ossicles; Ossicular Replacement; Deafness; Ossicular Prosthesis; Treatment Outcome
PubMed: 36843520
DOI: 10.13201/j.issn.2096-7993.2023.03.010 -
Micromachines Feb 2023Due to ethical issues and the nature of the ear, it is difficult to directly perform experimental measurements on living body elements of the human ear. Therefore, a...
Due to ethical issues and the nature of the ear, it is difficult to directly perform experimental measurements on living body elements of the human ear. Therefore, a numerical model has been developed to effectively assess the effect of the replacement of artificial ossicles on hearing in the inner ear. A healthy volunteer's right ear was scanned to obtain CT data, which were digitalized through the use of a self-compiling program and coalescent Patran-Nastran software to establish a 3D numerical model of the whole ear, and a frequency response of a healthy human ear was analyzed. The vibration characteristics of the basilar membrane (BM) after total ossicular replacement prosthesis (TORP) implantation were then analyzed. The results show that although the sound conduction function of the middle ear was restored after replacement of the TORP, the sensory sound function of the inner ear was affected. In the low frequency and medium frequency range, hearing loss was 5.2~10.7%. Meanwhile, in the middle-high frequency range, the replacement of a middle ear TORP in response to high sound pressure produced a high acoustic stimulation effect in the inner ear, making the inner ear structures susceptible to fatigue and more prone to fatigue damage compared to the structures in healthy individuals. This developed model is able to assess the effects of surgical operation on the entire hearing system.
PubMed: 36838183
DOI: 10.3390/mi14020483