Quantitative analysis of the skull in the Japanese wolf (Canis lupus hodophilax) using CT.

In this study using computed tomography (CT), the volumes of the internal cranial cavities, such as the braincase, frontal sinus and tympanic cavity, and the ratio of the volume of each cavity to the skull volume in Japanese wolves were quantified, and CT images of the frontal sinus were observed. The results were then compared with those of other wolf subspecies, including Akita, a dog breed, to clarify the characteristics of the internal cranial cavities in Japanese wolves. The present study revealed that the Japanese wolf had a relatively larger braincase volume and a relatively smaller frontal sinus volume than the wolf ssp. (a group of wild wolf subspecies except the Japanese wolf) and Akita. Moreover, the relative and absolute tympanic cavity volumes of the Japanese wolf and Akita were significantly smaller than those of the wolf ssp. In the CT image or macroscopic observations, the frontal sinuses of the wolf ssp. and Akita were relatively well developed to the caudal and dorsal directions, respectively, compared with that of the Japanese wolf, and the tympanic cavity of the wolf ssp. was more largely swelled ventrally and medially than that of other groups.

[Role of intratympanic glucocorticoid treatment in sudden hearing loss]. / Stellenwert der intratympanalen Glukokortikoidtherapie in der Behandlung des Hörsturzes.

Idiopathic sudden sensorineural hearing loss (ISSNHL) is one of the most common diseases in otolaryngology. Its etiology remains unknown. Furthermore, there is only a low level of evidence for the efficacy of established treatment modalities. In addition to systemic glucocorticoids, intratympanic corticosteroid treatment (ICT) has become increasingly important for treatment of ISSNHL. Different application strategies and treatment regimens have been described; however, uniform standards do not yet exist. ICT may be used for primary treatment as well as salvage therapy. Current data from meta-analyses show no benefit of intratympanic versus systemic primary therapy for sudden hearing loss (moderate evidence) but suggest a benefit of intratympanic secondary treatment over no treatment or placebo (high effect size, low evidence). Regarding combination of systemic and local glucocorticoid therapy in primary treatment of hearing loss, there may be a small benefit over systemic treatment alone (low effect size, low evidence).

Review of the caroticotympanic nerves: Anatomy, function and pathology.

The caroticotympanic nerves provide postganglionic sympathetic fibres to the tympanic plexus. However, there are scant reports in the literature detailing with these nerves in great depth. As the caroticotympanic plexus lies near the often-operated tympanic nerve, it is important for the surgeon to understand the anatomy, pathology and surgical implications of it. Here, we present a review of the available literature regarding the caroticotympanic nerves.

Cavitation processes in a space filled with loose mesenchymal tissues: a comparison between the retrosternal space and the middle ear tympanic cavity in human fetuses.

BACKGROUND: During the expansion of the pleural cavity in early fetuses, a thick sheet of loose mesenchymal tissue (SLMT) appears between the lung bud and body wall. Subsequently, the growing lung bud invades into the SLMT and the latter becomes fragmented to disappear. To compare this with the tympanic cavity filled with loose mesenchymal tissues, the present study aimed to demonstrate the development, establishment, and breaking of the SLMT in the retrosternal space. MATERIALS AND METHODS: Although the retrosternal tissue was almost absent or very thin at 7 weeks, the SLMT appeared behind the manubrium sterni at 8 weeks. Accordingly, at 9-10 weeks, cavitation occurred in the SLMT to expand the pleural cavity. Therefore, the volume of SLMT was not determined by the adjacent structures such as the pericardium and sternum. Likewise, mesenchymal tissues filling the middle ear disappeared after 26 weeks. RESULTS: There were considerable individual variations in the timing of beginning and location of the tympanic cavitation. However, in contrast to the retrosternal SLMT, the volume of the future tympanic cavity is determined by the adjacent hard tissue and tympanic membrane much earlier than the cavitation. The mesenchymal tissue carried abundant vessels in the middle ear but none or few veins in the retrosternal SLMT. CONCLUSIONS: The concept that the lung bud invades into the splanchnic mesoderm to expand the pleural cavity seems oversimplified. Mechanical stresses from the pleural cavity might induce retrosternal cavitation, while a loss in blood supply might cause tympanic cavitation.

Staged Surgery for Intra-Extracranial Communicating Jugular Foramen Paraganglioma: A Case Report and Systematic Review.

Staged surgery strategy was preferred for patients with intra-extracranial communicating jugular foramen paraganglioma (IECJFP). A female patient who presented mild tinnitus, headache, and dizziness, together with preoperative related imaging, was diagnosed with a left intra-extracranial communicating jugular foramen lesion in November 2015 and accepted an initial operation for the intracranial tumor by retrosigmoid approach. The pathologic report was paraganglioma. In November 2021, a subtotal resection of the extracranial tumor was conducted for prominent lower cranial nerves (LCNs) deficit and middle ear involvement by infratemporal approach. In patients with IECJFP accompanied by LCNs deficit and middle ear involvement, an initial surgery for extracranial lesion and a second procedure for intracranial tumor were appropriate. However, the first operation for the intracranial lesion was preferred in IECJFP cases without LCNs deficit and middle ear involvement, as it could remove compression to the neurovascular structure and brain stem, clarify a pathological diagnosis, avoid a CSF leak, and prevent a severe neurological disorder from extracranial lesion excision. Subtotal resection of the extracranial tumor would be performed when lesion became larger combined with obvious LCNs disorder and tympanic cavity involvement. Consideration of specific staged surgical strategy for IECJFP in accordance with preoperative LCNs deficit and tympanic cavity involvement could prevent critical postoperative neurological deficit and improve quality of life in the long term.

Unmitigated negative nasopharyngeal pressure is associated with attic retraction pocket formation: LaPlace's law in action.

BACKGROUND: Decades of clinical observation have led our subspecialty team to suspect that negative nasopharyngeal pressure is associated with attic retraction pocket formation. Furthermore, LaPlace's law, which states that the pressure within a sphere varies with the inverse of the radius, provides the dynamic explanation for why the attic area of the tympanic membrane tends to retract more frequently than the pars tensa. METHODS: The attic retraction pockets of 154 patients were classified into grades of severity (grades I-V). Impedance audiometry of middle-ear pressure was measured in the resting state, and after sniffing, swallowing and the Valsalva manoeuvre. RESULTS: Negative nasopharyngeal pressure (sniffing) caused a diminution of middle-ear pressure of -5 daPa on average in normal ears, and of -24 daPa to -45 daPa for tympanic membranes with attic retraction pockets of grade I to grade V. CONCLUSION: Attic retraction pockets are associated with greater collapse of middle-ear volume when negative pressure is created in the nasopharynx. LaPlace's law, and the composition of the pars flaccida, suggests an explanation for why the attic region retracts more than the pars tensa.

Cartilage tympanoplasty for recurrent cholesteatoma using a single sliced cartilage graft: Our experience in 14 ears.

Our procedure may provide a useful alternative in cases where previous surgeries have failed to eradicate the cholesteatoma.

[Eustachian tube drug delivery to the tympanum in patients with otitis media with effusion]. / Otsenka transtubarnoi dostavki lekarstvennykh preparatov v barabannuyu polost' pri ekssudativnom srednem otite.

There are no reliable data on the volume of the drug reaching the affected tympanic cavity during the catheterization of Eustachian tube (ET). Objective: to conduct an experiment and to study the effectiveness of administering a drug into the tympanic cavity of the middle ear using an original ear catheter, which allows catheterization of ET in the direction of its lumen. The study included patients with unilateral OME (n=21, the duration of the disease from 2 to 3 months), who were recommended for the ventilation tube insertion. The main inclusion criterion was 3 degree of patency of the ET. The experiment was performed under endotracheal anesthesia. ET was catheterized before insertion of the ventilation tube, with a 0.9% saline in a volume of 7 ml, which was previously tinted with Brilliant Green. A syringe with a contrast solution was connected to an ear catheter and the drug was injected into the middle ear by the air-liquid substitution method. Otoscopically evaluated the following parameters: the volume of the injected drug (in ml) for the initial (V1), partial (V2) and complete filling of the tympanic cavity (V3). As a result, it was found that 18 patients (85.7%) achieved full or partial filling of the tympanic cavity with a stained preparation: V1=2.25 ml, V2=7.0 ml in 11 (52.4%) patients, V3=4.29 ml - in 7 (33.3%) patients. In this case, the minimum loss of the liquid form of the drug during CT catheterization is 1:2. In 3 (14.3%) patients there were no endoscopic signs of contrasting of the tympanic cavity.

[A case of eosinophil otitis media with smear-negative middle ear effusion and literature review].

We report a case of eosinophil otitis media with smear-negative middle ear effusion. This case is a special type of otitis media characterized by highly viscous middle ear effusion associated with bronchial asthma and nasal polyposis. However, unlike the classical cases that tested positive for eosinophils, smear examination of middle ear effusion in this case showed unusual presence of neutrophils. The diagnosis was validated by pathological biopsy of granulation tissue in the tympanic cavity, showing predominantly eosinophils in the mucosa of the middle ear. Surgery, focal applications of corticosteroid and antibiotics to control inflammation and bacterial infection were effective to ameliorate the middle ear condition in this case.

Microsurgical anatomy of the stapedius muscle in adult cadavers.

This study aimed to establish an extended morphometric dataset regarding the stapedius muscle for anatomists and otologists. The tympanic cavity of ten cadavers (five females, five males) aged with 75.70 ± 13.75 years was bilaterally dissected. Morphometric properties of the stapedius muscle (i.e., its muscular belly and tendon) and its relationship with the neighborhood structures including the facial nerve was evaluated. The length of the entire stapedius muscle was found as 4.80 ± 1.13 mm. The depth between the entrance of the external auditory canal and stapedius muscle was measured as 18.23 ± 2.30 mm. The incudostapedial joint and stapedial tendon were found to be 1.66 ± 0.25 mm and 1.18 ± 0.19 mm away from the facial nerve, respectively. The stapedial tendon length was standardized as five types: Type 1, extremely short tendon (under 0.5 mm), 5% of cases; Type 2, short tendon (between 0.5 and 1 mm), 30% of cases; Type 3, normal tendon (between 1 and 2 mm), 55% of cases; Type 4, long tendon (between 2 and 2.5 mm), 10% of cases; and Type 5, extremely long tendon (above 2.5 mm), no cases. Our findings showed that the stapedius tendon size in adults was quite similar to fetuses. Therefore, probably entire muscle dimension does not alter after birth. Considering the concordance between direct anatomic (our findings) and radiologic measurements (literature findings) of the stapedius muscle, preoperative radiological evaluation may be important for otologists in terms of the choice of surgical tools such as diamond burr sizes. Due to the lack of standardization regarding the evaluation of the stapedius tendon size (i.e., extremely short or extremely long), we defined the tendons below 0.5 mm as extremely short (Type 1) and above 2.5 mm as extremely long (Type 5).

The outcomes of endoscopic myringoplasty: packing with gelatin sponge versus packing with nothing.

Background: Packing with gelatin sponge has long been widely used in myringoplasty. However, there is no research on packing with nothing.Aims/objectives: To analyse the differences between packing with gelatin sponge and packing with nothing.Material and methods: Patients with tympanic membrane perforation were randomly divided into a packing with gelatin sponge group and a packing with nothing group. Differences between the groups were compared.Results: The operation time of group A (34.00 ± 1.05 min) was significantly shorter than that of group B (42.20 ± 1.40 min; p < .00); 1 patient (2.86%) in group A and 35 patients (100%) in group B had a dry ear time of longer than 1 week (p < .001). Ten patients (28.57%) in group A and 24 patients (68.57%) in group B had aural fullness after the operation (p < .001). The air-bone gap (ABG) in group A was smaller than that in group B at 1 week, 1 month, 2 months and 3 months after the operation (p < .05).Conclusion and significance: Group A achieved the same good results, but it had a short operation time, an early dry ear time, a low incidence of aural fullness and early recovery of hearing.

Prenatal development of the sound transmitting apparatus in different embryonic stages of Malpolon monsspesulanus (squamata-serpentes) / Desenvolvimento pré-natal do aparelho transmissor de som em diferentes estágios embrionários de Malpolon monsspesulanus (Squamata-serpentes)

Abstract The developmental investigation of sound transmitting apparatus is important in understanding the ontogenetic processes behind morphological diversity. The development of sound conducting apparatus was studied in Montpellier snake; Malpolon monspessulanus at 6.5, 7.2, 8.3 and 9.3 cm total body lengths using light microscopy study. The columella auris firstly appeared as undifferentiated rod shape mesenchymal cells. As the growth proceeded, it chondrified and differentiates into two main parts. In addition, the viscerocranium components which participate in formation of sound transmitting apparatus undergo critical organization. In more advanced stages, procartilagenous stylohyal chondrified and fuse with the well organized quadrate. These data considered as a base for functional and molecular mechanisms of sound transmitting apparatus studies and identification of diseases that may infect them.

Resumo A investigação do desenvolvimento de equipamentos de transmissão de som é importante na compreensão dos processos ontogenéticos atrás diversidade morfológica. O desenvolvimento de aparelhos de som realização foi estudada em Montpellier cobra; Monspessulanus Malpolon em 6.5, 7.2, 8.3 e 9.3 cm corporal total utilizando comprimentos de estudo de microscopia de luz. O auris columelar em primeiro lugar apareceu como células mesenquimais forma haste indiferenciada. Como o crescimento passou, ele chondrified e diferencia em duas partes principais. Além disso, os componentes viscerocrânio que participam na formação do aparelho de transmissão de som submeter a organização crítico. Em estágios mais avançados, stylohyal procartilagenous chondrified e se fundem com o quadrado bem organizado. Estes dados considerados como uma base para os mecanismos funcionais e estudos moleculares do aparelho de transmissão de som e identificação de doenças que podem infectar-los.

[The topographical and anatomical characteristic of the anterior part of the external auditory passage and the tympanic cavity]. / Topografoanatomicheskaia kharakteristika perednego otdela naruzhnogo slukhovogo prokhoda i barabannoi polosti.

The objective of the present work was to overview the currently available literature data on microtopographic anatomy of the anterior portion of the middle ear and the external auditory passage. Manipulations on these structures during miringoplasty surgery appear to be the most difficult and laborious operations because this space is anatomically very narrow and curved; moreover, it contains the important intimate structures of the middle ear and is located very close to the temporomandibular joint. The knowledge of microsurgical anatomy of the anterior part of the middle ear and the external auditory passage is paramount in the context of the improvement of the professional skills of the surgeons. The current literature data provide a basis for the conclusion that many aspects of microsurgical anatomy of the anterior part of the tympanic cavity and the external auditory passage thus far remain poorly explored. This assertion is especially true as regards the relief of the mucous membrane overlying these structure and their supply with arterial blood. Further clarification of these aspects is needed.

Morphogenesis of the Middle Ear during Fetal Development as Observed Via Magnetic Resonance Imaging.

Recently, our research group has utilized serial histological sections to investigate the morphogenesis of the middle ear, which corresponds to the period of middle ear ossicle (MEO) cartilage formation. However, research regarding middle ear development during the post-embryonic period has been limited. In the present study, we investigated morphogenesis of the middle ear in human fetuses with a crown-rump length (CRL) between 37 and 197 mm using high-resolution magnetic resonance imaging (MRI). Our findings indicated that the morphology of the MEOs is similar during fetal development and adulthood; further, growth of the MEOs nearly ceases once a CRL of 150 mm is attained. In each MEO, ossification spreads from a single center. The malleus and Meckel's cartilage could be discriminated in samples exhibiting a CRL of 145 mm based on differences in MRI signal intensity. In samples with a CRL of 86 mm, the tympanic cavity (TC) appeared as a thin yet distinct structure attached to the external auditory meatus at the convex surface. Only the handle of the malleus was covered by the TC, while the incus and stapes contacted the cavity at the region of articulation between the two ossicles only, even after a CRL of 145 mm had been attained. Thus, although the TC increased in both diameter and thickness, coverage did not extend across all three MEOs during the observation period. These data are expected to provide a useful standard for morphogenesis and may aid researchers in distinguishing between normal and abnormal development. Anat Rec, 301:757-764, 2018. © 2017 Wiley Periodicals Inc.

The human otitis media with effusion: a numerical-based study.

Otitis media is a group of inflammatory diseases of the middle ear. Acute otitis media and otitis media with effusion (OME) are its two main types of manifestation. Otitis media is common in children and can result in structural alterations in the middle ear which will lead to hearing losses. This work studies the effects of an OME on the sound transmission from the external auditory meatus to the inner ear. The finite element method was applied on the present biomechanical study. The numerical model used in this work was built based on the geometrical information obtained from The visible ear project. The present work explains the mechanisms by which the presence of fluid in the middle ear affects hearing by calculating the magnitude, phase and reduction of the normalized umbo velocity and also the magnitude and phase of the normalized stapes velocity. A sound pressure level of 90 dB SPL was applied at the tympanic membrane. The harmonic analysis was performed with the auditory frequency varying from 100 Hz to 10 kHz. A decrease in the response of the normalized umbo and stapes velocity as the tympanic cavity was filled with fluid was obtained. The decrease was more accentuated at the umbo.

Microbiomes of the normal middle ear and ears with chronic otitis media.

OBJECTIVE: The aim of this study was to profile and compare the middle ear microbiomes of human subjects with and without chronic otitis media. STUDY DESIGN: Prospective multicenter cohort study. METHODS: All consecutive patients undergoing tympanoplasty surgery for chronic otitis media or ear surgery for conditions other than otitis media were recruited. Sterile swab samples were collected from the middle ear mucosa during surgery. The variable region 4 of the 16S rRNA gene in each sample were amplified using region-specific primers adapted for the Illumina MiSeq sequencer (Illumina, CA, USA)). The sequences were subjected to local blast and classified using Metagenome@KIN (World Fusion, Tokyo, Japan). RESULTS: In total, 155 participants were recruited from seven medical centers. Of these, 88 and 67 had chronic otitis media and normal middle ears, respectively. The most abundant bacterial phyla on the mucosal surfaces of the normal middle ears were Proteobacteria, followed by Actinobacteria, Firmicutes, and Bacteroidetes. The children and adults with normal middle ears differed significantly in terms of middle ear microbiomes. Subjects with chronic otitis media without active inflammation (dry ear) had similar middle ear microbiomes as the normal middle ears group. Subjects with chronic otitis media with active inflammation (wet ear) had a lower prevalence of Proteobacteria and a higher prevalence of Firmicutes than the normal middle ears. CONCLUSION: The human middle ear is inhabited by more diverse microbial communities than was previously thought. Alteration of the middle ear microbiome may contribute to the pathogenesis of chronic otitis media with active inflammation. LEVEL OF EVIDENCE: 2b. Laryngoscope, 127:E371-E377, 2017.

Morphological Variations of Middle Ear Ossicles and its Clinical Implications.

INTRODUCTION: The middle ear ossicles form a semi rigid chain in the middle of the ear for conduction and amplification of sound waves from the tympanic membrane to the inner ear. Although, our knowledge of the ear ossicles dates back to the 15th century, and various studies have been carried out on their morphometry, morphology, anomalies, embryology, function and structure throughout the world, information about the morphology of middle ear ossicles is meagre in Indian subjects. AIM: To find out the morphological variations of middle ear ossicles of right and left sides. MATERIALS AND METHODS: In the present study, the middle ear ossicles were bilaterally dissected out from the temporal bones obtained from 26 cadaveric heads from the Department of Anatomy under a surgical oto-microscope with micro instruments. Morphological variations were studied under the magnification of the operating microscope. Attempt was also made to evaluate the clinical implications related to such variants and compare the results with those observations made in other parts of India and abroad. Age variation was not considered as the ossicles reach their full size at birth. RESULTS: It was observed that the stapes was the most variable and the incus as the most stable ossicle so far as morphological variations are concerned. Malleus presented variations in the free ends of manubrium, lateral process and anterior process. Variation in morphology of stapes did not follow any fixed pattern. CONCLUSION: It is expected that this work may also inspire many others to continue temporal bone dissection with a view to gather more ossicles which might be preserved in ossicular banks by following proper sterilization methods for future use as homografts in ossiculoplasty. These harvested ossicles may be used to replace eroded middle ear ossicles as an alternative to manufactured prosthesis.

Autologous human nasal epithelial cell sheet using temperature-responsive culture insert for transplantation after middle ear surgery.

Postoperative mucosal regeneration of the middle ear cavity and the mastoid cavity is of great importance after middle ear surgery. However, the epithelialization of the mucosa in the middle ear is retarded because chronic inflammation without epithelialization aggravates gas exchange and clinical function. These environmental conditions in the middle ear lead to postoperative retraction and adhesion of the newly-formed tympanic membrane. Therefore, if the mucosa on the exposed middle ear bone surface can be rapidly regenerated after surgery, the surgical treatments for cholesteatoma and adhesive middle ear disease can potentially be improved. In this study, we successfully generated a cell sheet designed for the postoperative treatment of cholesteatoma. We used nasal cells to create an artificial middle ear mucosal cell sheet with a three-dimensional (3D) configuration similar to that of the middle ear mucosa. The sheets consisted of multi-layered mucosal epithelia and lower connective tissue and were similar to normal middle ear mucosa. This result indicates that tissue-engineered mucosal cell sheets would be useful to minimize complications after surgical operations in the middle ear and future clinical applications are expected. Copyright © 2015 John Wiley & Sons, Ltd.

Prenatal development of the sound transmitting apparatus in different embryonic stages of Malpolon monsspesulanus (squamata-serpentes)

Abstract The developmental investigation of sound transmitting apparatus is important in understanding the ontogenetic processes behind morphological diversity. The development of sound conducting apparatus was studied in Montpellier snake; Malpolon monspessulanus at 6.5, 7.2, 8.3 and 9.3 cm total body lengths using light microscopy study. The columella auris firstly appeared as undifferentiated rod shape mesenchymal cells. As the growth proceeded, it chondrified and differentiates into two main parts. In addition, the viscerocranium components which participate in formation of sound transmitting apparatus undergo critical organization. In more advanced stages, procartilagenous stylohyal chondrified and fuse with the well organized quadrate. These data considered as a base for functional and molecular mechanisms of sound transmitting apparatus studies and identification of diseases that may infect them.

Resumo A investigação do desenvolvimento de equipamentos de transmissão de som é importante na compreensão dos processos ontogenéticos atrás diversidade morfológica. O desenvolvimento de aparelhos de som realização foi estudada em Montpellier cobra; Monspessulanus Malpolon em 6.5, 7.2, 8.3 e 9.3 cm corporal total utilizando comprimentos de estudo de microscopia de luz. O auris columelar em primeiro lugar apareceu como células mesenquimais forma haste indiferenciada. Como o crescimento passou, ele chondrified e diferencia em duas partes principais. Além disso, os componentes viscerocrânio que participam na formação do aparelho de transmissão de som submeter a organização crítico. Em estágios mais avançados, stylohyal procartilagenous chondrified e se fundem com o quadrado bem organizado. Estes dados considerados como uma base para os mecanismos funcionais e estudos moleculares do aparelho de transmissão de som e identificação de doenças que podem infectar-los.

Finite element modelling of sound transmission from outer to inner ear.

The ear is one of the most complex organs in the human body. Sound is a sequence of pressure waves, which propagates through a compressible media such as air. The pinna concentrates the sound waves into the external auditory meatus. In this canal, the sound is conducted to the tympanic membrane. The tympanic membrane transforms the pressure variations into mechanical displacements, which are then transmitted to the ossicles. The vibration of the stapes footplate creates pressure waves in the fluid inside the cochlea; these pressure waves stimulate the hair cells, generating electrical signals which are sent to the brain through the cochlear nerve, where they are decoded. In this work, a three-dimensional finite element model of the human ear is developed. The model incorporates the tympanic membrane, ossicular bones, part of temporal bone (external auditory meatus and tympanic cavity), middle ear ligaments and tendons, cochlear fluid, skin, ear cartilage, jaw and the air in external auditory meatus and tympanic cavity. Using the finite element method, the magnitude and the phase angle of the umbo and stapes footplate displacement are calculated. Two slightly different models are used: one model takes into consideration the presence of air in the external auditory meatus while the other does not. The middle ear sound transfer function is determined for a stimulus of 60 dB SPL, applied to the outer surface of the air in the external auditory meatus. The obtained results are compared with previously published data in the literature. This study highlights the importance of external auditory meatus in the sound transmission. The pressure gain is calculated for the external auditory meatus.