RESUMO
The chemical and dimensional stability associated with suitable fracture toughness and propitious tribological characteristics make silicon nitride-based ceramics potential candidates for biomedical applications, mainly as orthopedic implants. Considering this combination of properties, silicon nitride components were investigated in relation to their biocompatibility. For this study, two cylindrical implants were installed in each tibia of five rabbits and were kept in the animals for 8 weeks. During the healing time, tissue tracers were administrated in the animals so as to evaluate the bone growth around the implants. Eight weeks after the surgery, the animals were euthanized and histological analyses were performed. No adverse reactions were observed close to the implant. The osteogenesis process occurred during the entire period defined by the tracers. However, this process occurred more intensely 4 weeks after the surgery. In addition, the histological analyses showed that bone growth occurred preferentially in the cortical areas. Different kinds of tissue were identified on the implant surface, characterized by lamellar bone tissue containing osteocytes and osteons, by a noncalcified matrix containing osteoblasts, or by the presence of collagen III, which may change to collagen I or remain as a fibrous tissue. The results demonstrated that silicon nitride obtained according to the procedure proposed in this research is a biocompatible material.
Assuntos
Materiais Biocompatíveis/farmacologia , Teste de Materiais , Compostos de Silício/farmacologia , Animais , Condução Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/anatomia & histologia , Corantes , Feminino , Microscopia de Fluorescência , Microscopia de Polarização , Próteses e Implantes , Coelhos , Cloreto de TolônioRESUMO
The application of bioactive coatings onto orthopaedic appliances is commonly performed to compensate for the otherwise bioinert nature of medical devices and to improve their osseointegration. Calcium phosphates, hydroxyapatite (HAp), and bioglasses are commercially available for this purpose. Until recently, few other inorganic compounds have been identified with similar biofunctionality. However, silicon nitride (Si3 N4 ) has emerged as a new orthopaedic material whose unique surface chemistry also enhances osteoconductivity. Recent research has confirmed that its minority intergranular phase, consisting of silicon yttrium aluminum oxynitride (SiYAlON), is principally responsible for this improvement. As a result, it was hypothesized that SiYAlON itself might serve as an effective osteoconductive coating or glaze for medical devices. To test this hypothesis, a process inspired by traditional ceramic whiteware glazing was developed. A slurry containing ingredients similar to the intergranular SiYAlON composition was applied to a Si3 N4 surface, which was then subjected to a heat treatment to form a glaze. Various analytical tools were employed to assess its chemistry and morphology. It was found that the glaze was comprised predominately of Y5 Si3 O12 N, a compound commonly referred to as N-apatite, which is isostructural to native HAp. Subsequent exposure of the glazed surface to acellular simulated body fluid led to increased deposition of biomimetic HAp-like crystals, while exposure to Saos-2 osteosarcoma cells in vitro resulted in greater HAp deposition relative to control samples. The observation that SiYAlON exhibits enhanced osteoconductivity portends its potential as a therapeutic aid in bone and tissue repair. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1084-1096, 2018.
Assuntos
Condução Óssea/efeitos dos fármacos , Próteses e Implantes , Líquidos Corporais/química , Regeneração Óssea , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Equipamentos e Provisões , Humanos , Osseointegração , Compostos de Silício/química , Propriedades de Superfície , Difração de Raios XRESUMO
In an attempt to view the effects of the efferent vestibular system (EVS) on peripheral dynamic vestibular function, we have monitored the Vestibular short-latency Evoked Potential (VsEP) evoked by pulses of bone conducted vibration during electrical stimulation of the EVS neurons near the floor of the fourth ventricle in the brainstem of anesthetized guinea pigs. Given the reported effects of EVS on primary afferent activity, we hypothesized that EVS stimulation would cause a slight reduction in the VsEP amplitude. Our results show a substantial (>50%) suppression of the VsEP, occurring immediately after a single EVS current pulse. The effect could not be blocked by cholinergic drugs which have been shown to block efferent-mediated vestibular effects. Shocks produced a short-latency P1-N1 response immediately after the electrical artifact which correlated closely to the VsEP suppression. Ultimately, we have identified that this suppression results from antidromic blockade of the afferent response (the VsEP). It would appear that this effect is unavoidable for EVS stimulation, as we found no other effects.
Assuntos
Condução Óssea , Potenciais Evocados , Tempo de Reação , Núcleos Vestibulares/fisiologia , Estimulação Acústica , Animais , Condução Óssea/efeitos dos fármacos , Estimulação Elétrica , Potenciais Evocados/efeitos dos fármacos , Feminino , Cobaias , Masculino , Inibição Neural , Neurônios Aferentes/fisiologia , Neurônios Eferentes/fisiologia , Agonistas Nicotínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Tempo de Reação/efeitos dos fármacos , Fatores de Tempo , Núcleos Vestibulares/efeitos dos fármacosRESUMO
OBJECTIVE: To examine the efficacy and safety of mastoid cavity obliteration using highly purified beta-tricalcium phosphate (beta-TCP) after mastoidectomy in middle ear surgery. PATIENTS: Thirteen patients with cholesteatoma invading the mastoid cavity or showing severe pathologic changes in the mastoid cavity. INTERVENTION: Twelve patients underwent mastoid obliteration with highly purified beta-TCP during the first- and/or second-stage operation of a 2-stage canal-up operation: 5 patients during the first and second stages, and 7 patients during the second stage only. One patient with cholesteatoma underwent mastoid obliteration with highly purified beta-TCP during a 1-stage canal-up operation. In total, beta-TCP was applied in 18 ear operations. MAIN OUTCOME MEASURES: All patients underwent multislice computed tomography (CT) before and after surgery to assess the condition of the middle ear. The amount of residual beta-TCP granules in the mastoid cavity was assessed using the following granular shadow grading scale: Grade 0, no granular shadow in the mastoid cavity; Grade 1, residual granular shadows in part of the mastoid cavity; and Grade 2, granular shadows in most of the mastoid cavity. To assess any harmful effect of beta-TCP implanted in the mastoid cavity, continuous postoperative discharge and delayed wound healing were recorded. In addition, the bone conduction threshold was assessed using pure-tone audiometry, and the patients were asked whether they experienced vertigo or dizziness during the postoperative follow-up. RESULTS: All the patients who underwent multislice CT less than 11.4 months after mastoid cavity obliteration with beta-TCP were Grade 2 on the granular shadow grading scale, whereas all those who underwent multislice CT more than 53.8 months after mastoid obliteration were Grade 0. No patient had continuous postoperative discharge, delayed wound healing, or extrusion of beta-TCP granules. No patient showed deterioration of the bone conduction threshold more than 10 dB after mastoid cavity obliteration with highly purified beta-TCP or complained of postoperative vertigo or dizziness. CONCLUSION: Highly purified beta-TCP may be safe and reliable for mastoid obliteration. Highly purified beta-TCP may also be useful in other surgical procedures, including posterior wall reconstruction of the external auditory canal and scutum plasty.
Assuntos
Fosfatos de Cálcio/uso terapêutico , Colesteatoma da Orelha Média/cirurgia , Orelha Média/cirurgia , Processo Mastoide/cirurgia , Procedimentos Cirúrgicos Otológicos/efeitos adversos , Complicações Pós-Operatórias/tratamento farmacológico , Condução Óssea/efeitos dos fármacos , Colesteatoma da Orelha Média/complicações , Orelha Média/patologia , Humanos , Processo Mastoide/patologia , Complicações Pós-Operatórias/patologia , Tomografia Computadorizada por Raios X , TimpanoplastiaAssuntos
Anticonvulsivantes/toxicidade , Carbamazepina/toxicidade , Emergências , Epilepsias Parciais/tratamento farmacológico , Perda Auditiva Súbita/induzido quimicamente , Perda Auditiva Súbita/diagnóstico , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/farmacocinética , Audiometria de Tons Puros , Condução Óssea/efeitos dos fármacos , Carbamazepina/administração & dosagem , Carbamazepina/farmacocinética , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Humanos , Masculino , Nistagmo Patológico/induzido quimicamente , Nistagmo Patológico/diagnóstico , Otoscopia , Testes de Função VestibularRESUMO
OBJECTIVES: This study analyzed the long-term hearing loss after treatment of primary nasopharyngeal carcinoma to elucidate its causal factors. METHODS: Ninety-two nasopharyngeal carcinoma patients were treated with radiotherapy or chemoradiotherapy. Pure tone audiometry was performed before the therapy and annually up to 9 years after completing treatment. The hearing thresholds were corrected for age-related deterioration and compared to the results without adjusting for age. RESULTS: The mean air and bone conduction threshold with and without correction for age-related deterioration differed significantly 2-9 years after completing radiotherapy (p < 0.05). The audiometry results with age correction showed a flattened configuration compared to the results without age correction. The total radiation dose and radiation modality showed a causal relationship with a greater incidence of hearing loss after therapy (p < 0.05). There was more deterioration in the air and bone hearing thresholds with conformal radiotherapy than intensity-modulated radiotherapy (p < 0.001). A radiation dose >72 cGy resulted in more severe hearing loss than <72 cGy (p < 0.05). CONCLUSION: Hearing loss after completing therapy should be corrected for age-related hearing deterioration to reveal the true extent to which the loss is a therapeutic complication. Both the radiation modality used and the dose were significantly associated with hearing loss.
Assuntos
Perda Auditiva/etiologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/etiologia , Radioterapia Conformacional/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Adulto , Idoso , Audiometria de Tons Puros/métodos , Condução Óssea/efeitos dos fármacos , Carcinoma , Terapia Combinada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Dosagem Radioterapêutica , Adulto JovemRESUMO
UNLABELLED: In a family with IH, a rare high turnover bone disease, two older siblings were wheelchair-bound with severe skeletal deformity by age 15. Their youngest affected sibling was treated intensively with intravenous bisphosphonates for 3 years. The treatment was well tolerated and prevented the development of deformity and disability. INTRODUCTION: Idiopathic hyperphosphatasia (IH, also known as juvenile Paget's disease) is a rare genetic bone disease characterized by very high bone turnover and progressive bony deformity. Inhibitors of bone resorption have been used to suppress bone turnover in the short term, but there is no published data on long-term efficacy. MATERIALS AND METHODS: An 11-year-old girl with IH, who had two severely affected older siblings, presented with progressive deformity and deafness and long bone fractures. Conventional pediatric doses of pamidronate had failed to prevent clinical deterioration or suppress bone turnover completely. Intensive bisphosphonate therapy (frequent 5-mg ibandronate infusions) was given to try and arrest progression of the skeletal disease. Growth and development, pure tone audiometry, biochemistry, radiology, densitometry (DXA), and bone histology were monitored. RESULTS: A total of 45 mg ibandronate was given over 3 years until skeletal maturity was reached (20, 15, and 10 mg for years 1-3, respectively). Ibandronate treatment was well tolerated, and biochemical markers of bone turnover suppressed to within the age-appropriate normal range There was some progression of her thoracic kyphosis, but she had no further fractures and remained mobile and active at an age when her siblings had become wheelchair-bound. A significant recovery of hearing (p < 0.01) was documented, particularly at low frequencies. Radiographs showed improvement in spinal osteoporosis and cortical bone dimensions and arrest of progressive acetabular protrusion. Areal bone density increased substantially (lumbar spine z-score from -2.2 to + 1.8). Tetracycline-labeled bone biopsy specimens were taken before and after 18 months of intensive treatment. The second biopsy showed suppression of bone turnover and a doubling of trabecular thickness, with no mineralization defect, and no osteopetrosis. CONCLUSIONS: Intensive bisphosphonate treatment prevented the development of deformity and disability and improved hearing in this child with IH. The dose of bisphosphonate, which is substantially greater than is usually used in pediatric bone disease, had no adverse effects, in particular on bone mineralization.
Assuntos
Difosfonatos/uso terapêutico , Osteíte Deformante/tratamento farmacológico , Fosfatase Alcalina/sangue , Audiometria de Tons Puros , Biomarcadores/sangue , Biomarcadores/urina , Biópsia , Condução Óssea/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea , Criança , Colágeno/urina , Colágeno Tipo I , Feminino , Humanos , Ácido Ibandrônico , Infusões Intravenosas , Osteíte Deformante/diagnóstico por imagem , Osteíte Deformante/metabolismo , Osteíte Deformante/patologia , Pamidronato , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/efeitos dos fármacos , Ossos Pélvicos/patologia , Peptídeos/urina , Radiografia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/patologia , Resultado do TratamentoRESUMO
Bone defects were surgically produced in the tibiae of rabbits and medicated with freeze-dried methylpyrrolidinone chitosan. Histological observations 60 d after surgery showed a considerable presence of neoformed bone tissue, as opposed to controls, originating from the pre-existing bone as well as from the periosteum. The cationic nature and the chelating ability of the methylpyrrolidinone chitosan apparently favoured mineralization. Endosteal-periosteal and bone marrow osteoblast-like precursors, stimulated by growth factors entrapped in the coagulum-polysaccharide mixture, gave rise to intramembranous bone formation. The ultrastructural examination evidenced that bone osteoid was followed by mineralization of the tissue.
Assuntos
Condução Óssea/efeitos dos fármacos , Quitina/análogos & derivados , Quitosana , Modelos Animais de Doenças , Osteoblastos/efeitos dos fármacos , Pirrolidinonas/farmacologia , Animais , Desenvolvimento Ósseo/efeitos dos fármacos , Doenças Ósseas/tratamento farmacológico , Regeneração Óssea/efeitos dos fármacos , Quitina/farmacologia , Feminino , Luz , Microscopia , Microscopia Eletrônica , Coelhos , Tíbia/cirurgiaRESUMO
The effect of thyroid hormone injection on the development of auditory function in neonatal rats was evaluated using auditory nerve-brainstem evoked responses (ABR). The hormone induced earlier onset of auditory function. In order to differentiate between conductive and sensorineural factors, both air-conducted (AC) and bone-conducted (BC) ABR responses were recorded. Neonatal rats were injected with thyroxine (T4), or with saline (control animals), from day of birth (post-natal day-PND-0), daily, until PND 9. AC- and BC-ABRs were recorded from PND 6 up to PND 20. It was found that both AC- and BC-ABR thresholds were lower in the T4-injected rats up to PND 15, after which no difference was found between the two groups. This indicated earlier maturity of both conductive (external and middle ears) and sensorineural (inner ear) factors and is probably due to the earlier appearance in the blood of higher T4 levels, following injection, than that occurring naturally during the neonatal period in these animals.
Assuntos
Limiar Auditivo/efeitos dos fármacos , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Tiroxina/farmacologia , Animais , Animais Recém-Nascidos , Condução Óssea/efeitos dos fármacos , Meato Acústico Externo/efeitos dos fármacos , Meato Acústico Externo/fisiologia , Ratos , Nervo Vestibulococlear/efeitos dos fármacosRESUMO
Little is known about cisplatin ototoxicity in pediatric patients. Measurement of otoacoustic emissions is a rapid, reproducible, objective method of evaluating hearing. We examined whether transient-evoked otoacoustic emissions in pediatric patients exposed to cisplatin in the past correlated with audiographic findings. Twelve patients were entered into the study (mean age at treatment 7.8 years, mean cumulative dose 442.5 mg/mm2, mean 7.1 doses). Hearing at 3000 Hz was preserved in 82.6% of patients. In the higher frequencies significant sensorineural hearing loss was noted: 43.5% at 4 kHz; 81.0% at 6 kHz; and 90.5% at 8 kHz. Transient-evoked otoacoustic emissions were measurable in 11 of 12 patients. Middle ear disease accounted for abnormal otoacoustic emission seen in three patients (1 with effusion, 2 with significant negative middle ear pressure). When the middle ear was normal, a statistically significant correlation was seen between the transient-evoked otoacoustic emissions reproducibility and pure-tone threshold (correlation coefficient = -0.69, p = 0.008). Increased hearing loss was also associated with young age at first dose of cisplatin (p = 0.044), high number of chemotherapy cycles (p = 0.042), and high cumulative dose (p = 0.042).
Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Cóclea/efeitos dos fármacos , Potenciais Evocados Auditivos/efeitos dos fármacos , Adolescente , Adulto , Fatores Etários , Antineoplásicos/administração & dosagem , Audiometria de Tons Puros , Audiometria da Fala , Limiar Auditivo/efeitos dos fármacos , Limiar Auditivo/fisiologia , Condução Óssea/efeitos dos fármacos , Condução Óssea/fisiologia , Criança , Pré-Escolar , Cisplatino/administração & dosagem , Cóclea/fisiologia , Otopatias/fisiopatologia , Orelha Média/fisiopatologia , Potenciais Evocados Auditivos/fisiologia , Feminino , Audição/efeitos dos fármacos , Audição/fisiologia , Perda Auditiva de Alta Frequência/induzido quimicamente , Perda Auditiva de Alta Frequência/fisiopatologia , Perda Auditiva Neurossensorial/induzido quimicamente , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Otite Média com Derrame/fisiopatologia , Projetos Piloto , Pressão , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
OBJECTIVES: The purpose of this study was to evaluate the safety and efficacy of a modified intratympanic gentamicin technique in patients with intractable unilateral or bilateral Meniere's disease. METHODS: A retrospective review of 25 consecutive patients who underwent gentamicin treatment for Meniere's disease was conducted between 1992 and 1996. Two separate delivery systems were used during this study, with the last 13 subjects undergoing placement of the new system (flanged polyethylene tubing). RESULTS: Follow-up averaged 23 months. Absence of vertigo spells was reported in 88%, and substantial control was achieved in 12%. Four of five patients with bilateral disease achieved complete control. Results for the two delivery systems were not significantly different. Absence of ice-water caloric response was seen in 75% (15 of 20) patients. Clinically significant sensorineural hearing loss occurred in 5 (20%) of 25 ears. Nonserviceable hearing developed in only two (8%) patients. CONCLUSIONS: Our results support the previously reported efficacy and relative safety of gentamicin infusion therapy for intractable Meniere's disease. Polyethylene tubing may be more advantageous than T-tube delivery because of anatomic concerns in certain patients.
Assuntos
Antibacterianos/uso terapêutico , Gentamicinas/uso terapêutico , Doença de Meniere/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Audiometria de Tons Puros , Audiometria da Fala , Condução Óssea/efeitos dos fármacos , Testes Calóricos/métodos , Sistemas de Liberação de Medicamentos , Orelha Média , Eletronistagmografia , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Gentamicinas/administração & dosagem , Transtornos da Audição/induzido quimicamente , Perda Auditiva Neurossensorial/induzido quimicamente , Humanos , Gelo , Intubação/instrumentação , Masculino , Pessoa de Meia-Idade , Polietilenos , Estudos Retrospectivos , Segurança , Percepção da Fala/efeitos dos fármacos , Resultado do Tratamento , Membrana Timpânica/cirurgia , Vertigem/prevenção & controleRESUMO
The progress of sensorineural hearing loss (SNHL) in patients with cochlear otosclerosis was compared for 19 patients treated with fluoride for 1-5 years and 22 untreated controls. CT scans of eight patients before and after fluoride treatment were evaluated visually. Fluoride therapy arrested the progression of SNHL in the low (250, 500 and 1,000 Hz) (p < 0.001) and high (2 and 4 kHz) (p = 0.008) frequencies. It seemed to be more effective for the higher frequencies in cases with an initial SNHL of < 50 dB. Fluoride administration for 4 years did not seem to be superior to a shorter treatment period (1-2 years). For six patients followed up after discontinuing fluoride therapy there was minimal deterioration in SNHL. There was no clear relationship between the size and site of otospongiotic lesions on CT and the severity of SNHL. Follow-up with CT evaluation did not provide reliable information as to the efficacy of fluoride therapy.
Assuntos
Audiometria de Tons Puros , Fluoretos/administração & dosagem , Perda Auditiva Neurossensorial/tratamento farmacológico , Otosclerose/tratamento farmacológico , Fosfatos/administração & dosagem , Fluoreto de Sódio/administração & dosagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Limiar Auditivo/efeitos dos fármacos , Condução Óssea/efeitos dos fármacos , Feminino , Seguimentos , Perda Auditiva Neurossensorial/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Otosclerose/diagnóstico por imagem , Reprodutibilidade dos Testes , Resultado do TratamentoRESUMO
S-carboxymethylcysteine syrup (SCMC); brompheniramine, phenylephrine with phenylpropanolamine elixir (BPP); and a placebo were compared in a double-blind trial in 58 children with otitis media with effusion (OME). All patients underwent myringotomies after an initial period of medical treatment. SCMC, but not BPP, was significantly better than the placebo in speeding up resolution of the effusion after surgery, as judged by pure tone audiometry, showing this drug to be a useful adjunct to the surgical management of OME. It should also be considered as an alternative to surgery.
Assuntos
Carbocisteína/uso terapêutico , Cisteína/análogos & derivados , Otite Média com Derrame/tratamento farmacológico , Otite Média/tratamento farmacológico , Adolescente , Condução Óssea/efeitos dos fármacos , Bromofeniramina/uso terapêutico , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Audição/efeitos dos fármacos , Humanos , Masculino , Fenilefrina/uso terapêutico , Fenilpropanolamina/uso terapêuticoRESUMO
OBJECTIVE: To study the efficacy of combined use of rhBMP2/BCBand free periosteal graft in repairing segmental bony defects. METHODS: A new grafting material (rhBMP2/BCB) was made by combining recombinant human BMP2 (rhBMP2) and an antigen-free bovine cancellous bone (BCB) as a carrier. rhBMP2/BCB was used alone in conjunction with free periosteal graft to repair a 1.5 cm defect in the radius of the rabbit. The defect-repairing capability for each of the treatment modalities was assessed radiographically, biomechanically, and by densitometry and histological studies. RESULTS: rhBMP2/BCB used alone was capable of healing the defect in large by 16 weeks, with a similar repair process and mechanism seen with RBX. Combined use of rhBMP2/BCB and free periosteal graft was superior in terms of increased amount and quality of the new bone formed at the early stage of the repair process (within 12 weeks) to rhBMP2/BCB used in isolation, with the defect basically healed by 12 weeks. CONCLUSIONS: Both methods are effective in repairing segmental bony defects, with rhBMP2/BCB used in conjunction with free periosteal graft being most preferred, considering the satisfactory osteogenesis, osteoconduction and osteoinduction.
Assuntos
Proteínas Morfogenéticas Ósseas/farmacologia , Transplante Ósseo/métodos , Periósteo/transplante , Rádio (Anatomia)/cirurgia , Fator de Crescimento Transformador beta , Animais , Condução Óssea/efeitos dos fármacos , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/genética , Bovinos , Úmero/transplante , Osteogênese/efeitos dos fármacos , Coelhos , Rádio (Anatomia)/lesões , Proteínas Recombinantes/farmacologiaRESUMO
OBJECTIVES: (1) To determine the safety of using a commercially available suspension of polymyxin B, neomycin, and hydrocortisone (PNH) in tympanoplasty surgery. (2) To apply evidence-based medicine to tympanoplasty surgery when considering potential ototoxicity. STUDY DESIGN: Case series with chart review. SETTING: Tertiary otology practice, single surgeon. METHODS: Approval for this study was obtained from the St. Dominic-Jackson Memorial Hospital Institutional Review Board. Data were gathered on 272 consecutive type 1, underlay tympanoplasties for which both pre- and postoperative audiometric data were available over a 10-year period. In each surgery, gelatin sponge saturated in a commercially available PNH suspension was placed in the middle ear to support the graft. Patients ranged in age from 3 years to 79 years. Preoperative and postoperative bone conduction thresholds were measured at 500, 1000, 2000, 3000, and 4000 Hz. RESULTS: The average change in sensorineural hearing as measured by bone conduction thresholds was negligible, with a slight improvement in all frequencies tested except 4000 Hz. The changes by frequencies were as follows: 500 Hz (-1.624 dB), 1000 Hz (-1.399 dB), 2000 Hz (-0.975 dB), 3000 Hz (-0.596 dB), and 4000 Hz (+0.560 dB). The 5-frequency average change was -0.545 dB. CONCLUSIONS: The commonly used otic solution containing polymyxin B, neomycin, and hydrocortisone demonstrates no ototoxicity in tympanoplasty surgery and is safe to use in this setting.
Assuntos
Antibacterianos/administração & dosagem , Audição/efeitos dos fármacos , Neomicina/administração & dosagem , Polimixina B/administração & dosagem , Timpanoplastia , Adolescente , Adulto , Idoso , Limiar Auditivo , Condução Óssea/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND AND AIM OF THE WORK: Mesna is thiol compound proposed as chemical dissector in otolaryngologic surgery. The aim of this study was to address the issue of possible ototoxicity from topical administration of MESNA into the middle ear during otologic surgery. METHODS: Audiological findings of patients (n=55) who underwent canal wall up tympanomastoidectomy with the ancillary use of Mesna in 1-year period were retrospectively reviewed. We identified another set of 51 patients who had undergone otologic surgery without the use of Mesna to serve as a control group. Preoperative and postoperative mean bone conduction thresholds were calculated and compared between the two groups for the frequencies of 500,1000,2000, and 3000; 4000 and 8000 Hz were further analyzed to search for high-frequency sensorineural hearing loss. RESULTS: Fifty-five patients were operated on with the ancillary use of Mesna and 51 underwent surgery with traditional mechanical dissection alone. When mean preoperative bone conduction values were compared with postoperative values, no significant differences were found for any of the frequencies tested in both groups. Analyzing changes in bone conduction at 4000 and 8000 Hz a slight worsening was observed in both groups. CONCLUSIONS: We found no difference in hearing thresholds between the treatment and control groups. Thus, the results of this study confirmed data obtained in laboratory animal models demonstrating that intraoperative use of Mesna in middle ear surgery is safe and does not lead to ototoxic effects.
Assuntos
Condução Óssea/fisiologia , Colesteatoma da Orelha Média/cirurgia , Cóclea/efeitos dos fármacos , Mesna/uso terapêutico , Procedimentos Cirúrgicos Otológicos/métodos , Adolescente , Adulto , Idoso , Audiologia , Condução Óssea/efeitos dos fármacos , Colesteatoma da Orelha Média/tratamento farmacológico , Cóclea/fisiopatologia , Cóclea/cirurgia , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Substâncias Protetoras/uso terapêutico , Estudos Retrospectivos , Adulto JovemRESUMO
CONCLUSION: The standard treatment for tuberculous otitis media (TOM) without complications consists of anti-tuberculosis (anti-TB) medication, with which we experienced good treatment outcomes. However, surgery is required for recovery of anatomy and hearing function. OBJECTIVE: To determine the clinical characteristics of TOM that might optimize diagnosis and to evaluate the differences in clinical courses between patients treated with and without surgery. METHODS: We analyzed 14 patients (16 ears) who had been diagnosed and treated for TOM. Radiologic findings, laboratory data, and audiometry results were also evaluated. Patients were divided into a chemotherapy group and a surgery group according to treatment modality. RESULTS: Temporal bone CT (TBCT) showed total occupation of the tympanic cavity by soft tissue and little evidence of ossicular erosion. In the chemotherapy group, dry ears were obtained in all but one patient (14 ears) after treatment. Normalized tympanic membrane (TM) was found in 50% in the chemotherapy group and in 75% in the surgery group. The air-bone gap (ABG) changed from 40.3 +/- 2.5 dB to 47.0 +/- 19.2 dB in the chemotherapy group and from 35.2 +/- 7.6 dB to 30.2 +/- 11.4 dB in the surgery group. After treatment, ABG improved by > 10 dB in one ear in the chemotherapy group and in four ears in the surgery group.