[Hard of hearing, a forgotten public health problem].
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Communication Disorders↗
Biomedical subjects
J J Grote
Publications and source records attributed to J J Grote.
Long-term follow-up of chronic therapy resistant purulent rhinitis in children.
Forty children diagnosed as having chronic purulent rhinitis unresponsive to medical and surgical management were studied. After a mean follow-up of six years and nine months the condition resolved spontaneously in 95% of the children, usually after reaching the age of 7 years.
Age Factors↗
Long-term follow-up of chronic maxillary sinusitis in children.
In 26 children, aged between 3 and 7 years, the course of therapy-resistant chronic maxillary sinusitis over a mean period of 6 years and 3 months, was analysed. The results showed that spontaneous cure had occurred in 24 of the 26 children, on average after they reached the age of 7 years. The chronic character of upper respiratory tract infections in young children is difficult to explain.
Child↗
Ultrasonography as a method of examination of the frontal sinus.
This prospective study was performed to evaluate the reliability of ultrasonography for the detection of fluid and mucosal swelling in the frontal sinus. The evaluation was based on a comparison of the preoperative ultrasonographic results with the surgical findings in 27 frontal sinuses. Ultrasonography was found to be a reliable method for the demonstration or exclusion of mucosal swelling and accumulated fluid (sensitivity 92%; specificity 93%).
Evaluation Studies as Topic↗
Hearing loss in facioscapulohumeral muscular dystrophy.
The coincidence of facioscapulohumeral muscular dystrophy (FSHD) with sensorineural hearing loss and retinal abnormalities might imply genetic heterogeneity of FSHD. We performed screening audiometry in 56 patients with autosomal dominant FSHD and in 72 healthy family members, and found that the difference in hearing level between 4,000 Hz and 6,000 Hz was significantly greater in FSHD patients than in controls, independently both for the left and right ear. We conclude that this change of hearing function is part of the disease and may lead to severe hearing loss in some patients. The fact that it was present in all families is another argument against genetic heterogeneity.
Adolescent↗
Hydroxylapatite prosthesis.
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Durapatite↗
New alloplastic tympanic membrane material.
For patients with a totally empty middle ear a total alloplastic middle ear prosthesis (TAM) has been developed consisting of a macroporous hydroxyapatite canal-wall segment as a foundation system from which a dense hydroxyapatite ossicular chain is suspended. To connect the ossicular chain, we developed an alloplastic tympanic membrane made from a polymer. Light microscopy, morphometry, and autoradiography as well as various electron microscopy techniques were used in this study to evaluate the biocompatibility of Polyactive, a polyether polyester copolymer, after implantation in the rat middle ear. After between 2 and 4 weeks, implants were completely covered by tympanic-membrane epidermis and epithelium. Polyactive provoked a mild foreign-body reaction, showed a degradation rate of 54 percent after 1 year, and was nontoxic. Growth of fibrous tissue and bone into Polyactive copolymer indicated appropriate implant fixation by mechanical interlocking. The fixation of Polyactive by ingrowth of bone is promising, not only in terms of the amount of bone but also in terms of the bone/polymer interface. The latter is indicative of bonding osteogenesis in a way similar to that reported for hydroxyapatite implants. The results of this study showed that Polyactive copolymer is suitable as a degradable alloplastic tympanic membrane, both as a temporary scaffolding for the repair of tympanic membrane perforations and as a tympanic membrane in the TAM.
Animals↗
Tissue/biomaterial interface characteristics of four elastomers. A transmission electron microscopical study.
The tissue/biomaterial interface reactions of four elastomers--selected as candidates for scaffolding for tympanic membrane tissue in a total alloplastic middle ear prosthesis--were studied at the electron microscopical level after implantation in the rat middle ear. Time-dependent changes in the phagocyte/polymer interface suggested degradation of porous implants made of Estane polyether urethane, polypropylene oxide, and a poly(ethylene oxide hydantoin) and poly(tetramethylene terephthalate) segmented polyether polyester copolymer (HPOE/PBT copolymer), but not of dense Silastic silicone rubber implants. Silastic was always encapsulated in fibrous tissue. Contact between fibrous tissue and HPOE/PBT copolymer or Estane was established in the third month, but fibrous tissue was never seen close to polypropylene oxide. Bone made contact only with Estane and HPOE/PBT copolymer implants. The bone/copolymer interface showed an electron-dense layer morphologically similar to that seen between bone and hydroxyapatite ceramic, suggesting that with respect to bone HPOE/PBT copolymer behaves like a bioactive implant material. The electron-dense layer was absnet at the bone/Estane interface. Estane and especially HPOE/PBT copolymer seem to be suitable as alloplastic tympanic membrane because of their interface behavior with respect to fibrous tissue and bone.
Animals↗
The biocompatibility of hydroxyapatite ceramic: a study of retrieved human middle ear implants.
The biocompatibility of 11 hydroxyapatite auditory canal-wall prostheses and 4 hydroxyapatite incus prostheses implanted for 4 to 40 months was evaluated by light microscopy, scanning electron microscopy, transmission electron microscopy, and Röntgen microanalysis. These 15 prostheses representing 4% of 375 prostheses, has been removed because of unresolved chronic middle ear infection, residual cholesteatoma, or poor fit. The findings confirmed earlier reports on the biocompatibility of hydroxyapatite in vitro, in animals, and in man. An electron-dense layer was found at the interface with bone and fibrous tissue, and a firm bond between the ceramic and bone at the hydroxyapatite ceramic/bone interface developed. Macropores became filled with bone and fibrous tissue, and the tissue in the individual pores was interconnected. Furthermore the incus prostheses were covered with an epithelium similar to that found in the human middle ear. Findings diverging from those made in other studies were the relatively large amount of exudate in the pores, an apparent increase of degradation during infection, and the accumulation of trace elements in one of the canal-wall prostheses. In all likelihood these three phenomena may be attributed to the unfavorable conditions to which these prostheses were exposed during implantation.
Biocompatible Materials↗
Biocompatibility of a polyether urethane, polypropylene oxide, and a polyether polyester copolymer. A qualitative and quantitative study of three alloplastic tympanic membrane materials in the rat middle ear.
The biocompatibility of porous implants made of Estane 5714 F1 polyether urethane, polypropylene oxide, and a poly(ethylene oxide hydantoin) and poly(tetramethylene terephthalate) segmented polyether polyester copolymer (HPOE/PBT copolymer), which were selected as candidates for an alloplastic tympanic membrane, was assessed after implantation in rat middle ears for periods of up to 1 year. Implantation of the materials led to tissue reactions initially associated with the wound-healing process, whereas after 1 month not only the presence of macrophages and foreign-body giant cells surrounding the implant materials but also implant degradation were characteristic for a foreign-body reaction. Macrophages and foreign-body giant cells dominated the picture of the tissue surrounding polypropylene oxide. The altered morphology of these cells, the persistent infiltration of the implantation sites by exudate cells, and the premature death of five rats in the 1-year group suggest that polypropylene oxide degradation was accompanied by the release of toxic substances. Estane and copolymer degradation did not induce tissue responses reflecting implant toxicity, and tympanic membranes given these alloplasts showed a normal healing pattern. Inclusions in the cytoplasm of macrophages associated with degradation and phagocytosis of all of the polymers under study were found to contain iron, silicon, titanium, and aluminum. Growth of fibrous tissue and bone, the latter into Estane and HPOE/PBT copolymer implants, indicated appropriate implant fixation by tissue, although macrophages and foreign-body giant cells were present as well. Especially the fixation of copolymer by ingrowth of bone seems promising in terms of the amount of bone in the pores and the electron-dense bone/copolymer interface. The latter is indicative for bonding osteogenesis. The HPOE/PBT copolymer is a better candidate for alloplastic tympanic membrane than Estane, and the use of polypropylene oxide cannot be recommended.
Animals↗
The behavior of alloplastic tympanic membranes in Staphylococcus aureus-induced middle ear infection. I. Quantitative biocompatibility evaluation.
The biocompatibility of dense Silastic implants and porous implants made of Estane 5714 F1 polyether urethane, polypropylene oxide, and an HPOE/PBT segmented polyether polyester copolymer was evaluated during an induced Staphylococcus aureus middle ear infection. The middle ear response to infection seemed not to be affected by the presence of implants made of either of the polymers. Light microscopical morphometry and transmission electron microscopy showed degradation of the porous implants under study, but not of Silastic implants, which were invariably surrounded by a fibrous capsule. This finding, combined with the degree of porous implant degradation, the composition of the tissues surrounding the implants, and the tissue/biomaterial interface reactions are consistent with the results obtained in the noninfected middle ear. Round-cell infiltrates however, were predominantly associated with implants made of polypropylene oxide and HPOE/PBT copolymer; while the presence of (phagocytosed) microbial debris was associated with copolymer. The present findings indicate that with respect to implant behavior in infected surroundings Estane is the best porous material, whereas the behavior of Silastic implants did not deviate from that in non-infected ears.
Animals↗
The behavior of alloplastic tympanic membranes in Staphylococcus aureus-induced middle ear infection. II. Morphological study of epithelial reactions.
Epithelial reactions to Silastic, Estane polyether urethane, polypropylene oxide, and a poly(ethylene oxide hydantoin) and poly(tetramethylene terephthalate) segmented polyether polyester copolymer were investigated after implantation in tympanic membranes and submucosa of noninfected and Staphylococcus aureus-infected rat middle ears. Porous implants made of Estane and polypropylene oxide were completely covered by tympanic-membrane connective tissue, epidermis, and epithelium in 2 weeks and those made of copolymer in between 2 and 4 weeks postoperatively. Silastic implants, which were dense, were not enveloped by tympanic-membrane tissue but rejected. Starting in the 6th postoperative month the proliferative activity and structure of both the tympanic membrane epithelium and epidermis became normal except for the presence of iron-containing secretory epithelium near polypropylene oxide. After initial swelling caused by the surgical trauma, neither the proliferative activity nor the composition of the epithelium covering submucosal implants was affected by the presence of any of the biomaterials. Infection of middle ears bearing implants induced epithelial reactions similar to those associated with infected middle ears without an implant.
Animals↗
Otitis media with effusion and chronic upper respiratory tract infection in children: a randomized, placebo-controlled clinical study.
This study was performed to investigate the course of spontaneous recovery from otitis media with effusion in children with chronic rhinosinusitis treated in various ways. One hundred forty-one children between 3 and 10 years of age were selected for the presence of chronic rhinosinusitis and unilateral or bilateral otitis media with effusion. The children were assigned at random to one of four treatment groups, i.e., placebo, amoxicillin combined with xylometazoline hydrochloride nose drops, maxillary sinus drainage, or a combination of the latter two forms of therapy. The follow-up period was 6 months. Drainage of the maxillary sinus had no effect on either the recovery of the chronic upper respiratory tract infection or otitis media with effusion. Amoxicillin combined with xylometazoline nose drops had no significant effect on recovery from the upper respiratory tract infection, but did have a small but significant effect on recovery from otitis media with effusion. However, the general tendency of the upper respiratory tract and ears to recover was poor. Persistence of the chronic upper respiratory tract infection during the follow-up period proved to be a negative prognostic factor with respect to cure of otitis media with effusion. Children with chronic rhinosinusitis as defined in this study appear to have a high risk of developing chronic otitis media with effusion. The results of the study are discussed.
Amoxicillin↗
Reconstruction of the middle ear with hydroxylapatite implants: long-term results.
The results are reported of reconstructions of the middle ear with hydroxylapatite implants performed between 1980 and 1986 with an average follow-up of 5 years. The findings concern 120 canal wall prostheses made of hydroxylapatite. It was possible to reconstruct a radical cavity with a new ear canal. The results obtained with ossiculoplasty in 170 patients are reported. In patients lacking an incus, an incus prosthesis made of hydroxylapatite gave air-bone gap closure to within 20 dB in 83.3% of the patients. Extrusion was not observed. In cases with the stapes superstructure and incus both missing, an incus/stapes prosthesis made of hydroxylapatite gave an air-bone gap closure to within 20 dB in 75.7% of the cases, when used as an assembly. Extrusion was not observed. When the prosthesis was used as a columella, the results were less favorable (41.1%), and two prostheses were extruded during the postoperative control period. Recurrent cholesteatoma was not seen in cases in which eradication and reconstruction were staged.
Adolescent↗
Biocompatibility of clinically applied hydroxylapatite ceramic.
The biocompatibility of 11 porous canal wall prostheses and 4 dense incus prostheses, both types made of hydroxylapatite, was studied by light microscopy, scanning electron microscopy, transmission electron microscopy, and x-ray microanalysis. The duration of implantation varied between 4 and 40 months, and the 15 retrieved implants constitute 4% of the 375 clinically applied hydroxylapatite prostheses involved in this study. With respect to integration characteristics, coverage by epithelium and fibrous tissue, and biodegradation, the performance of clinically applied hydroxylapatite generally resembled that seen in animal experiments. However, the reactions during chronic infection in the human ear were more severe than those in experimentally induced acute infections in the rat middle ear. One of the canal wall prostheses showed trace element accumulation in the cytoplasm of phagocytes.
Biocompatible Materials↗
The diagnostic value of transillumination for maxillary sinusitis in children.
In 52 children between 3 and 9 years of age drainage of the maxillary sinus was performed because of chronic purulent rhinitis and opacity of the maxillary sinuses on the radiographs. The results of preoperative transillumination were compared with the drainage findings. In this selected group of children the sensitivity of transillumination for the demonstration of congestion in the maxillary sinuses was found to be limited. The authors consider transillumination to be an obsolete method for this purpose in children.
Child↗
Cytokeratin patterns of tissues related to cholesteatoma pathogenesis.
Specimens of cholesteatoma matrix, meatal epidermis, and middle ear epithelium were removed during surgery, and immunohistochemical techniques were used to investigate cytokeratin expression. The use of five chain-specific anticytokeratin monoclonal antibodies and one broad specific anticytokeratin monoclonal antibody showed the divergent behavior of middle ear epithelium compared with the cytokeratin expression of the other two types of epithelium. Middle ear epithelium was characterized by the presence of cytokeratins 4, 8, 18, and 19, whereas in both cholesteatoma and meatal epidermis cytokeratin 10 predominated. Furthermore, cholesteatoma showed an infrequent focal presence of cytokeratins 4, 18, and 19. The similarity between cholesteatoma and meatal epidermis with respect to morphology, and the presence of cytokeratin 10 support an epidermal origin of cholesteatoma. However, a metaplastic origin cannot be excluded, because of the infrequent occurrence of a small amount of cytokeratins 4, 18, and 19 in cholesteatoma matrix that was not found in meatal epidermis but was a component of the cytokeratin pattern of middle ear epithelium.
Antibodies, Monoclonal↗
Biocompatibility of six elastomers in vitro.
The biocompatibility of two silicone rubbers, Silastic and Dow Corning Elastomer, and of a polyether and a polyester urethane, a polyether polyester copolymer, and polypropylene oxide was assessed in vitro. These elastomers were selected for assessment as a possible alloplastic tympanic membrane. For these studies use was made of rat middle ear mucosa explants and serially cultured epithelium. The quantitative results were based on epithelial growth curves, the morphological picture was based on the findings in epithelium, and the aging of a biomaterial was simulated. Epithelium morphology was investigated by scanning and transmission electron microscopy and x-ray microanalysis. Quantitative results showed that on Dow Corning Elastomer and polypropylene oxide, cell proliferation was significantly lower compared to normal growth curves. The morphological findings were negative for polypropylene oxide, and did not discriminate between the other biomaterials under study. The simulation results indicated better biocompatibility for the polyurethanes and the polyether polyester copolymer compared with that of polypropylene oxide and both silicone rubbers. Under the simulation conditions, cells exposed to Silastic showed silicon-containing inclusions. These in vitro results suggest that the biocompatibility of the polyurethanes and the polyether polyester copolymer is better than that of both silicone rubbers and polypropylene oxide.
Animals↗