Search results for "Ossicle"
showing 9 items of 9 documents
Disconnecting bones within the jaw-otic network modules underlies mammalian middle ear evolution
2019
The origin of the mammalian middle ear ossicles from the craniomandibular articulation of their synapsid ancestors is a key event in the evolution of vertebrates. The richness of the fossil record and the multitude of developmental studies have provided a stepwise reconstruction of this evolutionary innovation, highlighting the homology between the quadrate, articular, pre-articular and angular bones of early synapsids with the incus, malleus, gonial and ectotympanic bones of derived mammals, respectively. There are several aspects involved in this functional exaptation: (i) an increase of the masticatory musculature; (ii) the separation of the quadrate bone from the cranium; and (iii) the …
Bioactive Glass-Ceramics in Middle Ear Surgery An 8-Year Review
1988
An 8-year follow-up of Ceravital middle ear prostheses showed there was extremely good tolerance in the middle ear space. Incompatibility phenomena were not observed, and inflammatory reactions were neither caused nor supported by the implants. The tympanoplasties were always performed without interposition of cartilage between the tympanic membrane or the tympanic membrane graft and the disk-shaped portion of the implant, and extrusions were never observed. Long-lasting inflammatory processes appeared to destroy implants the same way they destroy ossicles. Transient inflammatory periods (such as episodes of purulent otitis media, which occurred soon after the prostheses were implanted) did…
BIOACTIVE GLASS CERAMIC
1983
The practicability of the bioactive glass ceramic Cernvitnl® in ear surgery was tested in animals. The histological findings are presented. Over the last 3 years implants of bioactive glass ceramic were used in humans. Prostheses for the total or partial reconstruction of the ossicular chain and the reconstruction of the bony wall of the outer ear canal were fashioned. We have conducted about 300 tympanoplasties and 60 total or partial reconstructions of the bony wall of the outer ear canal. The otoscopic and functional results were satisfactory.
Tissue reactions to glass ceramics in the middle ear
1981
The bioactive glass ceramic "Ceravital" was used to fashion prostheses for the replacement of various ossicles in the middle ear. They were tested in 70 rabbit ears, where they were accepted in osseous areas without formation of surrounding fibrous tissue. Histological examinations regularly showed an osseous bond with the surrounding bony tissue. Mucous membrane covered these ossicular chain prostheses and showed no evidence of inflammatory reactions. Glass ceramic implants were also used to reconstruct the ossicular chain and the posterior wall of the outer ear canal in 100 patients. The functional results were satisfactory in all cases.
Giovanni Filippo Ingrassia: A five-hundred year-long lesson.
2010
Giovanni Filippo Ingrassia was born five centuries ago in Regalbuto, a small town in the center of Sicily. After his medical course in Padua, under the guidance of Vesalius and Fallopius, he gained international fame as a physician and was recruited as a Professor of human anatomy in Naples and later in Palermo. He is remembered as "the new Galen" or "the Sicilian Hippocrates." He contributed to the knowledge of human anatomy through the description of single bones rather than the whole skeleton. In particular, he was the first to describe the "stapes," the "lesser wings of the sphenoid" and various other structures in the head (probably the pharyngotympanic tube) as well as in the reproduc…
High-frequency conductive hearing loss as a diagnostic test for incomplete ossicular discontinuity in non-cholesteatomatous chronic suppurative otiti…
2017
Chronic suppurative otitis media, with or without cholesteatoma, may lead to erosion of the ossicles and discontinuity of the ossicular chain. In incomplete ossicular discontinuity (IOD), partial erosion of the ossicles occurs, but some sound transmission is noted throughout the ossicular chain. High-frequency conductive hearing loss (HfCHL) has been considered a hallmark of incomplete ossicular discontinuity. This study aims to evaluate the use of HfCHL as a preoperative predictor of IOD in patients with non-cholesteatomatous chronic suppurative otitis media. The HfCHL test was defined as the preoperative air-bone gap (ABG) at 4 kHz minus the average of the ABG at 0.25 and 0.5 kHz. The tes…
Juvenile psammomatoid ossifying fibroma of Orbit-A rare case report and review of literature
2021
Fibro osseous lesions of the craniofacial skeleton are a benign condition in which the normal architecture of the bone is replaced by fibrous connective tissue with varying degrees of mineralization. JOF forms a special entity among the fibro osseous lesions because of its age of occurrence and its aggressive nature thereby mimicking a malignancy. The Juvenile Ossifying Fibromas were further subdivided into Psammomatoid and Trabecular variant based on their histopathological characteristics. They tend to differ in their mineralized portion with the trabecular variant showing woven bone while the psammamotoid shows lamellated and spherical ossicles in various shapes in a myxoid stroma interm…
What a New Model of Skeletal Homologies Tells Us About Asteroid Evolution1
2000
The Extraxial-Axial Theory (EAT) is applied to the body wall homologies of asteroids. Attempts to characterize major plate systems of asteroids as axial or extraxial, particularly those that are highly organized into series, can be problematic. However, the Optical Plate Rule (OPR) is instrumental in establishing that ambulacrals and terminals are axial. It is equally clear that the region aboral to the marginal frame is a part of the perforate extraxial body wall (with the possible exception of the centrodorsal, which is likely imperforate extraxial). Previously established EAT criteria, particularly those strongly rooted in the embryologically expressed boundary between axial and extraxia…
An Upper Mississippian echinoderm microfauna from the Genicera Formation of northern León (Carboniferous, Cantabrian Mountains, N Spain)
2020
For the first time an echinoderm microfauna is recorded from the cephalopod limestone facies (‘griotte facies’) of the lower Carboniferous (Mississippian) Genicera Fm. (Alba Fm.). The formation is widespread in the Cantabrian Mountains in NW Spain, but the ossicles are from some sections in the surroundings of the Bernesga valley in northern León. They have been derived from insoluble acetic acid residues from samples of the upper and especially of the uppermost part of the formation (Canalón Mb. and Millaró Beds). The microfauna include taxonomically treated wheel-shaped ossicles, sieve-plates and rods of holothurians, goniodonts of ophiocistioids, and ophiuroid and stenuroid skeletal elem…