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Concept: Middle ear

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The development of minimally invasive procedures such as the balloon dilation Eustachian tuboplasty (BET) is an alternative to the grommet tympanum membrane. BET is applied in the cases where, after elimination of all factors influencing the ET and middle ear functioning, no sufficient improvement is observed. The aim of this study was to present the therapeutic benefits of the BET method in the treatment of ETD caused by disorders in the middle ear ventilation. The BET procedure was offered to four patients (3 men and 1 woman) after subjective, physical, otorhinolaryngological and audiometric examinations including pure tone audiometry, tympanometry and pressure-swallow test. As the method was novel, preinterventional CT angiography of the carotid arteries was performed in all patients. Any complications were noticed during and after the procedure (bleeding or damage of regional mucosa) in any patients. Our clinical studies assessed the feasibility and safety of the BET during a short-term period-only a 6-week observation. Although patients revealed a significant improvement of ET score, longer long-term studies are necessary to determine whether this method will demonstrate lasting benefits and safety in the treatment of chronic Eustachian tube dysfunction. In other investigations, improvement was found to be time dependent.

Concepts: Scientific method, Auditory system, Common carotid artery, Middle ear, Eustachian tube, Otitis media, Ear, Patulous Eustachian tube

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Having three ossicles in the middle ear is one of the defining features of mammals. All reptiles and birds have only one middle ear ossicle, the stapes or columella. How these two additional ossicles came to reside and function in the middle ear of mammals has been studied for the last 200 years and represents one of the classic example of how structures can change during evolution to function in new and novel ways. From fossil data, comparative anatomy and developmental biology it is now clear that the two new bones in the mammalian middle ear, the malleus and incus, are homologous to the quadrate and articular, which form the articulation for the upper and lower jaws in non-mammalian jawed vertebrates. The incorporation of the primary jaw joint into the mammalian middle ear was only possible due to the evolution of a new way to articulate the upper and lower jaws, with the formation of the dentary-squamosal joint, or TMJ in humans. The evolution of the three-ossicle ear in mammals is thus intricately connected with the evolution of a novel jaw joint, the two structures evolving together to create the distinctive mammalian skull.

Concepts: Evolution, Auditory system, Middle ear, Paleontology, Malleus, Ossicles, Incus, Evolution of mammalian auditory ossicles

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A 20-year-old man was transferred to this hospital because of recurrent ear pain for 8 months despite antibiotics, with new fever and headache. Imaging showed opacification of the middle ears and mastoid air cells and erosion of the right temporal bone.

Concepts: Cartilage, Skull, Middle ear, Temporal bone, French Revolution, Bones of the head and neck, Mastoiditis, Jimmy Eat World

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Although robust algorithms for registration and segmentation are available, the majority of surgical approaches to the temporal bone are nowadays made without navigation assistance. Beside instrument navigation (IN), functions such as distance control (DC) and navigated control (NC) can be used. This study analyzes the application of these navigation functionalities in lateral skull base and middle ear surgery.

Concepts: Medicine, Physician, Skull, Al-Andalus, Middle ear, Temporal bone, Occipital bone, Squamosal

28

Acute otitis media (AOM) is a polymicrobial disease, which usually occurs as a complication of viral upper respiratory tract infection (URI). While respiratory viruses alone may cause viral AOM, they increase the risk of bacterial middle ear infection and worsen clinical outcomes of bacterial AOM. URI viruses alter Eustachian tube (ET) function via decreased mucociliary action, altered mucus secretion and increased expression of inflammatory mediators among other mechanisms. Transient reduction in protective functions of the ET allows colonizing bacteria of the nasopharynx to ascend into the middle ear and cause AOM. Advances in research help us to better understand the host responses to viral URI, the mechanisms of viral-bacterial interactions in the nasopharynx and the development of AOM. In this review, we present current knowledge regarding viral-bacterial interactions in the pathogenesis and clinical course of AOM. We focus on the common respiratory viruses and their established role in AOM.

Concepts: Infection, Inflammations, Middle ear, Eustachian tube, Respiratory system, Otitis media, Upper respiratory tract infection, Otitis externa

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Intranasal medication for eustachian tube dysfunction (ETD) is an established practice in otolaryngology through the effects of steroids, decongestants, antihistamines or a combination of the above in reducing tubal oedema. The author has previously argued that a double-blind, randomised control trial would be helpful in determining effectiveness of treatment, if a standardised head position, chiefly Mygind or Ragan, was adopted to maximise intranasal drop delivery into the eustachian tube orifice. One recent paper suggests that intranasal treatment is not very effective, but ultimately does not state whether a standardised head position was adopted. Although a large body of evidence supports the hypothesis that the nasal passages are the route to middle ear disease, there is as yet no paper that has been published that has specifically addressed this issue, therefore the author must conclude that evidence to support intranasal treatment for ETD is still lacking and further research is desirable.

Concepts: Randomized controlled trial, Effectiveness, Auditory system, Middle ear, Eustachian tube, Otitis media, Ear, Pseudoephedrine

27

Eustachian Tube Dysfunction is common, and implicated in persistent middle ear disease. Recent studies suggest the promise of balloon dilatation of the Eustachian tube to modify local anatomy and physiology, restoring normal function.

Concepts: Biology, Auditory system, Middle ear, Eustachian tube, Anatomy, Otitis media, Ear, Patulous Eustachian tube

27

Tebipenem pivoxil, an oral carbapenem antibiotic for pediatric use, exhibits excellent clinical effects on acute otitis media (AOM). The present study was conducted to assess the pharmacokinetic profile of tebipenem in middle ear effusion and to examine the clinical efficacy of tebipenem pivoxil by calculating the values of the pharmacokinetic-pharmacodynamic parameters (AUC/MIC, C (max)/MIC, and T > MIC) of tebipenem at the site of action. Twenty-three pediatric outpatients diagnosed with AOM were enrolled. Ear discharge or nasopharyngeal swabs collected before the onset of oral administration were used to conduct bacteriological examinations, and subjects were then treated by twice-a-day oral administration of tebipenem pivoxil 6 mg/kg. The clinical isolates of Streptococcus pneumoniae and Haemophilus influenzae were obtained from 10 and 19 pediatric patients (8 overlapped), respectively. On day 2 of administration, blood and middle ear effusion were collected from 20 pediatric patients to measure plasma and middle ear concentrations of tebipenem. Consequently, the C (max) and the AUC(0-∞) in plasma were 5.3 ± 1.6 μg/ml (mean ± SD) and 7.9 ± 0.2 μg h/ml, respectively. The C (max) in middle ear effusion of tebipenem was 1.2 ± 0.1 μg/ml, exceeding its MIC for these pathogens. The ratio of AUC(0-∞) in middle ear effusion to AUC(0-∞) in plasma was 0.36, showing the good transfer of tebipenem into the effusion; this result corroborated the known high rate of clinical efficacy of tebipenem pivoxil for patients with AOM and the low incidence of recurrence in them as manifested by the healing rate of 94.1 % (16/17).

Concepts: Pneumonia, Streptococcus pneumoniae, Ratio, Middle ear, Eustachian tube, Otitis media, Haemophilus influenzae, Otitis externa

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OBJECTIVE: The Eustachian tube is difficult to evaluate because it is located deep in the head. However, the introduction of 320-row area detector CT has made it possible to evaluate this region. In the present study, movement of the Eustachian tube during sniffing was visualized using area detector CT in patients with patulous Eustachian tube. METHODS: Four patients with patulous Eustachian tube were examined using an area detector CT scanner (Aquilion ONE, Toshiba). This scanner supports 320-row scanning of 0.5-mm slices at up to 0.275 s/rot., eliminating temporal mismatch between various parts of the acquired images and permitting 4-dimensional CT (4DCT) images to be obtained by continuous scanning. The scan conditions were 120 kV, 120 to 150 mA, 0.5 mm × 280 to 320 slices, and 0.35 seconds per rotation × 9 rotations. The patient was seated on a reclining chair tilted to 45 degrees and was instructed to sniff during continuous scanning. Images of the Eustachian tube were generated at 0.1-second intervals. CONCLUSION: At the start of sniffing, the cartilaginous portion of the Eustachian tube closed from the isthmus toward the pharynx. The starting point differed from patient to patient. In patients with patulous Eustachian tube, sniffing (an unconscious habit that helps to relieve ear discomfort) is an important factor in the development of middle ear diseases. We have successfully depicted this event for the first time, demonstrating various patterns of Eustachian tube closure during sniffing in patients with patulous Eustachian tube. This method may be useful for evaluating Eustachian tube dysfunction.

Concepts: Head and neck, Patient, Auditory system, Middle ear, Eustachian tube, Otitis media, Ear, Patulous Eustachian tube

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The diminutive middle ear ossicles (malleus, incus, stapes) housed in the tympanic cavity of the temporal bone play an important role in audition. The few known ossicles of Neandertals are distinctly different from those of anatomically modern humans (AMHs), despite the close relationship between both human species. Although not mutually exclusive, these differences may affect hearing capacity or could reflect covariation with the surrounding temporal bone. Until now, detailed comparisons were hampered by the small sample of Neandertal ossicles and the unavailability of methods combining analyses of ossicles with surrounding structures. Here, we present an analysis of the largest sample of Neandertal ossicles to date, including many previously unknown specimens, covering a wide geographic and temporal range. Microcomputed tomography scans and 3D geometric morphometrics were used to quantify shape and functional properties of the ossicles and the tympanic cavity and make comparisons with recent and extinct AMHs as well as African apes. We find striking morphological differences between ossicles of AMHs and Neandertals. Ossicles of both Neandertals and AMHs appear derived compared with the inferred ancestral morphology, albeit in different ways. Brain size increase evolved separately in AMHs and Neandertals, leading to differences in the tympanic cavity and, consequently, the shape and spatial configuration of the ossicles. Despite these different evolutionary trajectories, functional properties of the middle ear of AMHs and Neandertals are largely similar. The relevance of these functionally equivalent solutions is likely to conserve a similar auditory sensitivity level inherited from their last common ancestor.

Concepts: Human, Auditory system, Middle ear, Eardrum, Human evolution, Ossicles, Incus, Evolution of mammalian auditory ossicles