Showing papers in "European Archives of Oto-rhino-laryngology in 1986"
TL;DR: The unique presence of the cortex system in outerhair cells, and its absence in inner hair cells, indicates a functional significance that relates to a motor function of outer hair cells in hearing.
Abstract: Isolated outer hair cells were found to slowly shorten when subjected to a solution that would induce contraction in a muscle fibre. Two possible mechanisms underlying this behaviour emerge from ultrastructural and immunocytochemical investigations. Antibody labelling at the electron microscopic level demonstrates that actin is present not only in the stereocilia and in the cuticular plate but also along the wall of outer hair cells, between the plasma membrane and the subsurface fenestrated cisternae. The latter are interconnected by regularly spaced pillars, resembling those seen between the T-tubules and sarcoplasmic reticulum in muscle fibres. Contraction also results from the application of positively charged macromolecules to the bathing solution. This implies sensitivity of the membrane-associated complex (the cortex system) to an electrical current. A second contractile system may reside in the cytoplasm, where calmodulin is present in contracted hair cells. This protein is a calcium-binding control protein for contraction-like events in smooth muscle and non-muscle cells. The unique presence of the cortex system in outer hair cells, and its absence in inner hair cells, indicates a functional significance that relates to a motor function of outer hair cells in hearing.
285 citations
TL;DR: The temporal bone pathologies in 12 ears with idiopathic sudden sensorineural hearing loss are examined and it is found that the lesions present in these specimens and in 10 others reported in the literature are similar to lesions occurring in known cases of viral cochleitis.
Abstract: We examined the temporal bone pathologies in 12 ears with idiopathic sudden sensorineural hearing loss, and found that the lesions present in these specimens and in 10 others reported in the literature are similar to lesions occurring in known cases of viral cochleitis. These lesions are unlike those resulting from known vascular causes.
205 citations
TL;DR: It is believed that a poor blood supply is the major etiologic factor for the epithelial migratory disturbances of the tympanic membrane.
Abstract: An ink dot staining method was used to examine epithelial migration in normal ears, in pathologic tympanic membranes, and in external auditory canal cholesteatoma. The direction of the epithelial migration was found to coincide with that of the vessels in normal ears. This suggested that epithelial migration was controlled by the vessels which supply the epidermal layer of the tympanic membrane. In pathologic tympanic membranes and external auditory canal cholesteatomas, epithelial migration was disturbed to various degrees and depended on the local conditions. In these pathologic conditions, the tympanic membrane showed less vascularization. Based on our findings, we believe that a poor blood supply is the major etiologic factor for the epithelial migratory disturbances of the tympanic membrane.
87 citations
TL;DR: It is shown that exposure of the lateral and basal membrane parts of living isolated outer hair cells to increasing concentrations of potassium ions resulted in a sustained reversible cellular depolarization, which can explain the sudden tinnitus and parts of the hearing loss incurred as well as presumably the vertigo experienced.
Abstract: In addition to an endolymphatic hydrops in various models of Meniere's disease, ruptures of the membranes lining the endolymphatic spaces or massive changes in their biochemical permeability are believed to allow large amounts of potassium-rich endolymph to deluge the normally low [K+] perilymphatic fluid. Our clinic has shown that exposure of the lateral and basal membrane parts of living isolated outer hair cells to increasing concentrations of potassium ions resulted in a sustained reversible cellular depolarization. Furthermore, potassium intoxication was accompanied by a strictly longitudinal contraction of the hair cells present. This was followed by hair cell relaxation in the presence of artificial perilymph. These findings suggest a supplementary hypothesis for the clinical manifestations of Meniere's disease: (1) the reversible hair cell depolarization can explain the sudden tinnitus and parts of the hearing loss incurred as well as presumably the vertigo experienced; (2) the reversible longitudinal hair cell contraction induces an abnormal change of cochlear micromechanics, resulting in concomitant attacks of deafness and also possibly contributing to the tinnitus perceived.
63 citations
TL;DR: The major pathogenetic factors present were due to the transudation and injury of the middle ear epithelium disturbing mucociliary transport activity, with increased secretions participating somewhat in inducing the effusion.
Abstract: Lipopolysaccharide endotoxin (LPS) was extracted from Haemophilus influenzae type b by using Westphal's phenol water method. The ears of 40 adult male guinea pigs were subsequently inoculated with 10 μg/ml solutions of LPS by transmeatal injections. Groups of animals were then sacrificed from day 2 to day 24 after the injections to observe the pathological changes produced. Massive serous effusions filled the tympanic bullae on days 2 and 4, after which the amount of fluid present gradually decreased so that it could hardly be seen on day 11. Pathological changes found in the mucosa included marked interstitial edema, dilated capillaries, as well as elevated and thickened epithelium with intracellular edema. These findings gradually subsided by day 24. We believe that the major pathogenetic factors present were due to the transudation and injury of the middle ear epithelium disturbing mucociliary transport activity, with increased secretions participating somewhat in inducing the effusion. We further suggest that H. influenzae endotoxin may play an active role in the clinical development of otitis media with effusion.
58 citations
TL;DR: This paper found that the capability for speech discrimination correlated directly with the innervation density of the 15- to 22mm region (segment III) of the cochlea and showed an inverse relationship to pure-tone thresholds in the middle frequency range of 1 kHz to 2 kHz.
Abstract: Correlations were made between speech discrimination scores, pure-tone thresholds, and neuronal populations in 28 cochleae which were removed postmortem from elderly patients who had known premortem audiometric records. The predominant pathology present was loss of cochlear neurons. The capability for speech discrimination correlated directly with the innervation density of the 15- to 22-mm region (segment III) of the cochlea. Speech discrimination scores showed an inverse relationship to pure-tone thresholds in the middle frequency range of 1 kHz to 2 kHz.
56 citations
TL;DR: Posturographic data have allowed us to assess functional situations in a more precise way and any rehabilitation exercises used should be adapted according to these data.
Abstract: In patients with peripheral vestibular deficiencies, the testing of posture or “posturography” can give specific information about any compensation obtained in the vestibulospinal reflex (VSR). We have used the statokinesimetric parameter of length in this study. Nearly 50% of the patients with unilateral vestibular hypofunction as well as those patients with paroxysmal positional vertigo (PPV) show abnormal results. These findings indicate deficient compensation at the vestibulospinal level, which is independent of any compensation already achieved at the vestibulo-ocular level. The tests used for the latter, such as positioning and rotational tests, are unable to provide information about the degree of compensation reached in the VSR. The examinations used in the different modalities of sensory interaction can show the presence of influences of ocular fixation and changes of head position. We have observed three types of deviant interaction. Our posturographic data have allowed us to assess functional situations in a more precise way. Any rehabilitation exercises used should be adapted according to these data.
54 citations
TL;DR: The data has shown that the auditory dysfunction present in the inner ear was less marked than were the morphological changes seen, and suggest that other factors besides hyperlipoproteinemia are involved in the development of severe auditory damage.
Abstract: We sought to clarify whether or not hyperlipoproteinemia induces auditory dysfunction. In so doing, we studied the general states and cochlear pathologies of guinea pigs after the administration of a hyperlipid diet for 3 months. Serum biochemistries indicated marked elevations of cholesterol, high density lipoprotein (HDL)-cholesterol and low density lipoprotein (LDL) levels. An increased auditory threshold varying from 10 to 20 dB was observed in 40% of the guinea pigs using auditory brainstem responses. Histochemical study of the inner ear revealed variations in lipid metabolism and partial disorders of the outer hair cells. Electron microscopic observations showed vacuolar and parenchymal protrusions on the surfaces of the stria vascularis and Corti's organ, and vacuolar degeneration was seen around the capillary vessels of the vascular stria. Our data has shown that the auditory dysfunction present in the inner ear was less marked than were the morphological changes seen. Our findings suggest that other factors besides hyperlipoproteinemia are involved in the development of severe auditory damage.
48 citations
TL;DR: Findings indicate that there is some correlation between Ca++ activity and DC potential in the cochlear endolymph in guinea pigs, and this should not be considered a cause for concern.
Abstract: We found changes in Ca++ activity and DC potential during the development of experimentally induced endolymphatic hydrops in guinea pigs. These findings indicate that there is some correlation between Ca++ activity and DC potential in the cochlear endolymph.
44 citations
TL;DR: Naval endoscopy proves to be very helpful in detecting even “hidden” pathologies due to sinus disease in key areas in the middle meatus, and furthermore allows a direct visualization of the tubal orifice.
Abstract: Diseases of the paranasal sinuses--especially of the anterior ethmoid sinus--may affect tubal function. Acute and chronic sinus inflammations cause alterations in the normal pathways for secretions out of the sinus system. The normal secretion pathways usually bypass the orifice of the eustachian tube in the nasopharynx. Excessive or infected mucus can then be transported directly over the tubal orifice to cause its obstruction and promote ascending infections into the middle ear. We have found that nasal endoscopy proves to be very helpful in detecting even "hidden" pathologies due to sinus disease in key areas in the middle meatus, and furthermore allows a direct visualization of the tubal orifice. Functional endoscopic surgery has also enabled us to clear diseased and stenotic areas involving the sinus ostia with minimal procedures. Normal drainage and ventilation are reestablished via the physiologic sinus ostia and thus help to normalize tubal function.
43 citations
TL;DR: A tissue culture technique in which the ciliary activity of the cultured tubotympanum can be studied is introduced and it is found that ciliated cells of the eustachian tube and middle ear lining continued a beating activity during 168 h of observation.
Abstract: We have introduced a tissue culture technique in which the ciliary activity of the cultured tubotympanum can be studied. We have found that ciliated cells of the eustachian tube and middle ear lining continued a beating activity during 168 h of observation. The mean loss of activity of the ciliated cells from the eustachian tube or mucosal sites proximal to the tube was 20% or less, while that of mucosal sites distal to the tube was about 40% even after 168 h of cultivation in our culture medium of RPMI 1640. Our technique of tissue culture is available for studying the long-term effects of various therapeutic agents or adverse factors on the ciliary activity in the tubotympanum.
TL;DR: A method for measuring the orientation of cilia in the respiratory epithelium by measuring the angle between the plane defined by the central tubules and a reference line and considers this to be a normal variation in ciliary orientation.
Abstract: We have created a method for measuring the orientation of cilia in the respiratory epithelium. Ciliary orientation is the direction perpendicular to the plane defined by the central tubules of the cilia and is an estimate of ciliary beat direction. Ciliary orientation can be estimated by measuring the angle between the plane defined by the central tubules and a reference line. The standard deviation of these measurements describes the variation present in the beat directions of the cilia. The reference line must be so chosen that the majority of measurements falls at about the middle of the 0°–180° range. We tested measurements by using both a glass angle measure and a semiautomatic image analyzer (IBAS I). The latter approach was faster and more reproducible. We made our measurements of normal tissues on samples obtained from two healthy adult non-smokers. Measurements were made in four areas of each sample, with 59–110 cilia in each. The differences between the maximum and minimum angles of the ciliary orientation in the same area varied from 167.9° to 85.4° from the reference line. The standard deviation varied from 18.0° to 35.4° and we consider this to be a normal variation in ciliary orientation. Of the cilia, 57% were within a standard deviation of 20°.
TL;DR: The findings indicate that the epithelial degeneration occurring in traumatic olfactory dysfunction varies according to the degree of damage incurred and the time lapse present from injury.
Abstract: We devised our own instrument for obtaining biopsy specimens of human olfactory epithelium. We obtained specimens from two patients with anosmia caused by head trauma. The morphological changes in the olfactory epithelia were studied by light microscopy and transmission electron microscopy. With little damage or early stage of changes, the characteristic finding involved degeneration of the olfactory vesicles, especially with the disappearance of cilia. In the case of great damage and the final stage of injury, no olfactory vesicles were found at the epithelial surface and the olfactory epithelia presented a disorganized cellular arrangement of cells with an atrophic appearance. Our findings indicate that the epithelial degeneration occurring in traumatic olfactory dysfunction varies according to the degree of damage incurred and the time lapse present from injury.
TL;DR: The tracheal bioprosthesis is considered to be superior to cialit-preserved grafts and also to most other biological reconstruction procedures.
Abstract: We removed the tracheas from sacrificed laboratory animals and subjected this tissue to multi-step chemical processing. This method allowed us to preserve the cartilage and reduce its antigenicity, thus creating a bioprosthesis very similar to the host tissue. By using allogeneic and xenogeneic prostheses so prepared, no signs of immune rejections were seen following heterotopic or orthotopic implantations. The transplanted cartilage remained stable for periods ranging up to 21 weeks in recipient rats, while partial morphologic integrity of the cartilage was seen up to 1 year in pigs. Reepithelialization of the transplant with ciliated epithelium was completed in all specimens 12-24 weeks following surgery. Segmental replacement of up to one third of the whole trachea was possible in rats, whereas similar segmental replacements failed in pigs. We also found that successful reconstruction of window-shaped defects was possible. We consider our tracheal bioprosthesis to be superior to cialit-preserved grafts and also to most other biological reconstruction procedures.
TL;DR: In this paper, transmission electron microscopy was used to examine the cochlea of non-obese diabetic mice as animal models for human type I or non-insulin-dependent diabetes mellitus.
Abstract: We used transmission electron microscopy to examine the cochlea of non-obese diabetic mice as animal models for human type I or non-insulin-dependent diabetes mellitus. Pathological changes were observed in the organ of Corti of the basal turn and in the stria vascularis of each turn. Major findings in the stria vascularis were protrusion or condensation of marginal cells, swelling of intermediate cells, and widening of the intercellular spaces. Principal findings in the organ of Corti involved degenerative changes of the outer and inner hair cells and replacement of hair cells by supporting cells. No prominent pathological changes were observed in the capillaries. The possible mechanism of diabetic involvement in cochlear pathology is discussed.
TL;DR: An examination of photographs of the larynx indicates that the latter must be described in three dimensions: (1) medio-lateral, (2) antero-posterior, and (3) vestibule cross-sectional area.
Abstract: Most of the literature on voice quality focuses on the vocal folds while six other gestures involving the laryngeal entry and epilaryngeal structures are largely ignored. Whole organ tracer series histograms of the larynx are examined and suggestions are made as to which muscles and/or forces might cause these gestures. An examination of photographs of the larynx indicates that the latter must be described in three dimensions: (1) medio-lateral, (2) antero-posterior, and (3) vestibule cross-sectional area. The article is aimed at laryngologists in general, not surgeons in particular, and has implications for laryngology (being a putative model of diagnostic procedures), physiology (what forces create epilaryngeal configurations?), neuroscience (does the motor cortex control single muscles or whole gestures?), speech pathology (what is the ragbag called “hypertenseness”?), linguistics (how is one to describe lower pharynx phenomena?) and paralinguistics (what is the extrasystemic laryngeal component of voice quality?).
TL;DR: It is suggested that Ca++ may also have a significant role in abnormal states in the region of the endolymphatic sac.
Abstract: We measured Ca++ activity in the different parts of the endolymphatic space by using a doublebarrelled electrode with calcium liquid ionic exchanger. In the region of the endolymphatic sac, Ca++ activity (4.7×10−4
M) was much higher than in the cochlear duct (2.7×10−5
M) and semicircular canal (2.6×10−4
M). These findings suggest that Ca++ may also have a significant role in abnormal states.
TL;DR: It is shown that recovery to useful hearing levels tends to be spontaneous and independent of the type of medical treatment given, and currently available calcium antagonists of the nifedipine type are unable to enhance hearing recovery.
Abstract: In the treatment of patients with sudden deafness, we found no significant difference between an oral calcium antagonist (nifedipine) and intravenous naftidrofuryl given concomitantly with vitamin A, vitamin E, and zinc. This prospective randomized study in 50 patients again shows that recovery to useful hearing levels tends to be spontaneous and independent of the type of medical treatment given. Irrespective of their capability to prevent contractions of cerebral vascular smooth muscle induced by neurotransmitter and vasoconstrictor substances and of their rheological properties, currently available calcium antagonists of the nifedipine type are unable to enhance hearing recovery at the present time.
TL;DR: In this article, a prospective open and controlled study of perioperative antibiotics was conducted in patients with chronic otitis media (COM), where drug efficacy was found in a subgroup of 26 patients, who were characterized by preoperative aural drainage culturing Pseudomonas aeruginosa.
Abstract: A prospective open and controlled study of perioperative antibiotics was conducted in patients with chronic otitis media (COM). Drug efficacy was found in a subgroup of 26 patients, who were characterized by preoperative aural drainage culturing Pseudomonas aeruginosa. Fourteen of these patients were randomized to receive ceftazidime (cephalosporin) for 5 days at the operation, while 12 had no antibiotic treatment. The occurrence of subsequent aural drainage was compared with the actual clinical and microbiological conditions of the ears 2 months after the operation; statistically significant differences were found in favor of the group treated with ceftazidime. Further studies must define the role of ceftazidime and other antibiotics in the management of patients with COM.
TL;DR: It is indicated that the affinity of silver for membrane and neuronal structures and the deposition of silver as an insoluble compound (Ag2S) induce the progression of clinical disease.
Abstract: Generalized argyrosis can produce a number of abnormalities, including skin discoloration, liver and kidney dysfunction. We describe a patient with generalized argyrosis following long-term self-treatment with oral silver intake, in whom skin discoloration, progressive taste and smell disorders, vertigo and hypesthesia were observed. These findings were confirmed by chemosensory tests and electrophysiological investigations. The development of hypogeusia was assessed by subjective tests, while the progression of hyposmia was followed by recording olfactory evoked cortical potentials. Light and electron microscopy of tissue samplings demonstrated electron-dense mineral deposits in basal membranes, in macrophages, in the perineurium of peripheral nerves, along elastic and collagenous fibers, and in necrotic cells of the oral submucosa. Silver and sulfur deposits in affected tissues could be defined by X-ray microanalysis. The quantitative ratio between silver and sulfur in involved tissues was similar to that of an inorganic silver-sulfide (Ag2S) standard. The minute increase in the sulfur content when compared to the inorganic standard suggested a sulfur containing organic matrix of the tissue precipitates. Our findings indicate that the affinity of silver for membrane and neuronal structures and the deposition of silver as an insoluble compound (Ag2S) induce the progression of clinical disease.
TL;DR: A retrospective cross-sectional study on 183 patients with sudden hearing loss found that age at the onset of the hearing loss incurred is closely associated with the presence of concomitant diseases and partial or total recovery of hearing is strongly predicated by the variables of age at onset and the interval between onset of hearing loss and the beginning of treatment given.
Abstract: We have studied certain epidemiological problems not often encountered in the literature, involving patients with sudden hearing loss. We performed a retrospective cross-sectional study on 183 patients at the University of Padova and found that: (a) age at the onset of the hearing loss incurred is closely associated with the presence of concomitant diseases; (b) partial or total recovery of hearing is strongly predicated by the variables of age at onset and the interval between onset of hearing loss and the beginning of treatment given. We have also used polar-coordinate diagrams to show that cases of sudden hearing loss tend to be cyclic and are more prevalent in the central months of each season.
TL;DR: The cochleae of the spontaneously diabetic KK mice were examined by using transmission electron microscopy: protrusions of marginal cells, swellings of intermediate cells and widening of intercellular spaces were the main findings seen.
Abstract: We examined the cochleae of the spontaneously diabetic KK mice by using transmission electron microscopy At the age of 3 months, the mice started to show evidence for glycosuria and hyperglycemia, and tissue sections showed beginning cochlear pathology The pathological changes present were found to be limited to the stria vascularis: protrusions of marginal cells, swellings of intermediate cells and widening of intercellular spaces were the main findings seen These changes progressed with age, but were not observed in age-matched non-diabetic 57BL/6 mice The possible mechanism of diabetes causing cochlear pathology is discussed
TL;DR: No cases of hearing improvement were encountered in mumps deafness, while about 70% of sudden deafness showed improvement, when determining prognosis.
Abstract: We performed a 10-year comparative study on 95 cases (98 ears) of mumps deafness and 97 cases (97 ears) of profound sudden deafness and found the following results. The age of onset of deafness was less than 9 years in the majority of patients with mumps deafness, while it was frequently 30–50 years in those patients with sudden deafness. Among these latter patients, no cases occurred under 9 years of age. The incidence of tinnitus and vestibular symptoms was more frequent in the patients with sudden deafness, but no significant difference was noted in cases over 10 years of age. When determining prognosis, no cases of hearing improvement were encountered in mumps deafness, while about 70% of sudden deafness showed improvement.
TL;DR: It is suggested that sodium salicylate markedly reduces the ototoxic effect of furosemide, which may be mediated by an alteration of local or systemic prostaglandin metabolism, or may be due to inhibition of organic acid uptake in the cochlea.
Abstract: Furosemide is a loop diuretic which has been found to be ototoxic in humans and experimental animals. The ototoxic effects seem to be directed primarily towards the stria vascularis, since its shrinkage and extracellular edema have been observed in correlation with electrophysiologic changes. The present study was designed to examine the interaction of sodium salicylate and furosemide on the cochlear microstructures. Chinchillas weighing 400–600 g were used in all tests performed. The endocochlear potential (EP) was monitored continuously through a microelectrode inserted through the basilar membrane. A control group of animals was injected with 0.5 ml saline intravenously (IV) 30 min before 25 mg/kg furosemide was given. The experimental group of animals was injected with 50 mg/kg sodium salicylate IV 30 min before 25 mg/kg furosemide. The control animals were found to have a mean decrease in EP of 61.1 ±7.0 mV. In contrast, the experimental group had very little alteration of the EP following furosemide injection (18.7±3.9 mV). These findings suggest that sodium salicylate markedly reduces the ototoxic effect of furosemide. This effect may be mediated by an alteration of local or systemic prostaglandin metabolism, or may be due to inhibition of organic acid uptake in the cochlea.
TL;DR: The study of the complex relationship between nasal polyposis and ASA (acetylsalicylic acid) intolerance in 154 patients with nasal polyps was unable to find a specific mechanism to explain the relationship.
Abstract: We studied the complex relationship between nasal polyposis and ASA (acetylsalicylic acid) intolerance in 154 patients with nasal polyps. The clinical histories of all patients were reviewed, and diagnostic tests for immune or allergic causes and the responsiveness of patients to challenges with ASA-substitutive drugs were analyzed. A third of our patients tested were found to have positive personal histories of atopy and 35% showed ASA intolerance. Although 40% had bronchial asthma, only 16.8% of all patients had positive tests for allergy. We were unable to find a specific mechanism to explain the relationship between nasal polyposis and ASA intolerance and further investigations are still required.
TL;DR: Postoperatively, all of the patients showed improved dysphonia without secondary effects occurring from the collagen, and lessened aspiration was found in the authors' patient so affected.
Abstract: In 1962, Arnold used injectable Teflon to reintroduce Brunings' technique for rehabilitating the paralysed vocal cord. Although Teflon would not appear to be carcinogenic, the technique is not entirely trouble-free. Injectable collagen as a biological implant seems to be an attractive alternative since it is a component part of the extracellular protein matrix. In actual clinical use, the collagen is easily injectable, is well-tolerated by patients, and is only subject to limited resorption. It also undergoes some transformation into living connective tissue with neovascularization. Our study was carried out on 14 patients: 13 had vocal cord paralyses from various causes and 1 had vocal cord atrophy as a sequel to traumatic injury. The therapeutic indication for correction in all of these patients was dysphonia for which speech therapy had failed to produce an adequate result. One patient was found to suffer from symptomatic aspiration as well. The actual technique of surgery involved the injection of a mean quantity of 1.5 cc collagen into the submucosal tissue of the affected cord during direct laryngoscopy. Postoperatively, all of our patients showed improved dysphonia without secondary effects occurring from the collagen. We also found lessened aspiration in our patient so affected. Our period of follow-up to date ranges from 3-12 months.
TL;DR: It is shown that 24-h exposure to 300 ppm sulfur dioxide does not cause otitis media with effusion in the guinea pig since active ciliary function will prevent any secretions produced from stagnating in the tympanic cavity.
Abstract: We studied the mucosal pathology present in the eustachian tubes of guinea pigs following exposure to sulfur dioxide Secretory sthenia but with slight deterioration of ciliary activity was observed in the mucosal samples examined Our data have shown that 24-h exposure to 300 ppm sulfur dioxide does not cause otitis media with effusion in the guinea pig since active ciliary function will prevent any secretions produced from stagnating in the tympanic cavity
TL;DR: A case of an aggressive cementifying fibroma of the maxilla in a middle-aged male is described and the need for appropriate surgical management is emphasized.
Abstract: The cementifying fibroma is a benign fibro-osseous lesion. Its usual location is in the mandible while rare sites of involvement have been the maxilla and ectopic locations. These tumors are generally believed to originate from the connective tissue of the periodontal ligament. Clinically, lesions are usually asymptomatic, slow-growing, and well-circumscribed. However, in very few cases, particularly in younger patients, these tumors have demonstrated and apparent aggressive course of development. We describe a case of an aggressive cementifying fibroma of the maxilla in a middle-aged male. The pathogenesis of the tumor is discussed, and the need for appropriate surgical management is emphasized.
TL;DR: There was no clear difference in the degree of hearing improvement between the operated group and the conservatively treated group, but in both groups, an abruptly falling audiometric configuration was frequently found in the audiogram obtained at the stage of fixed hearing perception, suggesting the possibility that both groups may have a common lesion at the basal turn of the cochlea.
Abstract: We investigated 24 cases of idiopathic sudden progressive deafness (ISPD) in which worsening of sensorineural hearing loss after initial examination was confirmed by audiometry Exploratory tympanotomy was performed in 10 of 24 patients, and revealed perilymphatic leak in 4 patients However, there was a higher incidence and a more severe degree of vertigo and imbalance in the group that was operated on than in the non-operated group Our study has shown that there was no clear difference in the degree of hearing improvement between the operated group and the conservatively treated group In both of these groups, an abruptly falling audiometric configuration was frequently found in the audiogram obtained at the stage of fixed hearing perception, suggesting the possibility that both groups may have a common lesion at the basal turn of the cochlea
TL;DR: A rat animal model was used to study the ultrastructure of submucosal calcifications induced in the middle ear following inoculation with Streptococcus pyogenes and high doses of parenteral vitamin D3, and the morphological changes present in affected animals resembled the classical picture of tympanosclerosis.
Abstract: A rat animal model was used to study the ultrastructure of submucosal calcifications induced in the middle ear following inoculation with Streptococcus pyogenes and high doses of parenteral vitamin D3. The morphological changes present in affected animals resembled the classical picture of tympanosclerosis. While calcification occurred about bacterial remnants and myelin structures, the most important calcification centers were lysosomal and non-lysosomal matrix vesicles in the extracellular spaces. These formed band-like calcifications close to the basal membrane without affecting the epithelial layer. This animal model offers the possibility of studying the effect of various therapeutic regimens in the treatment of the dynamic tympanosclerotic process.