Design of a resilient ring for middle ear’s chamber stapes prosthesis

Abstract

This paper presents the process of designing a new elastic element replacing a membrane in the chamber stapes prosthesis (ChSP). The results of the study are volume displacement characteristics obtained for the prosthesis and physiological stapes. Simulation tests on a 3D CAD model have confirmed that a properly designed ring can stimulate perilymph with the same or greater efficacy as the physiological stapes footplate placed on the elastic annular ligament. The ChSP with a new elastic element creates a good chance of improving hearing in patients suffering from otosclerosis.     

Study of age-related changes in Middle ear transfer function

Abstract

Osteoporosis (OP) is common with advancing age. Several studies have shown a strong correlation between OP and otosclerosis. However, no studies have investigated OP of the malleus, incus or stapes in the human middle ear, its effect on middle ear transfer function. Here, we investigate whether these three ossicles develop OP, and how this affects middle ear transfer function. The effect of OP on middle ear transfer function was investigated in simulations based on a finite element (FE) method. First, the FE model used in our previous study was refined, and optimized by introducing viscoelastic properties to selected soft tissues of the middle ear. Then, the FE model was used to simulate OP of the three ossicles and assess its influence on middle ear transfer function. Other possible age-related changes, such as stiffness of the joints or ligaments in the middle ear, were also investigated. The results indicated that OP of the ossicles could increase the high frequency displacement of both the umbo and stapes footplate (FP). However, the stiffness of the middle ear soft tissue can lead to the decrease of middle ear gain at lower frequencies. Furthermore, loosening of these joints or ligaments could increase displacement of the umbo and stapes FP. In conclusion, although age-related hearing loss is most commonly conceived of as sensorineural hearing loss (SNHL), we found that age-related changes may also include OP and changes in joint stiffness, but these will have little effect on middle ear transfer function in elderly people.     

Recent Advances in the Treatment of Deafness

By the utilization of reconstructive procedures (tympanoplasty), middle ear and mastoid infections can be eliminated with the acquisition of a clean, dry ear in about nine out of 10 cases, and hearing can be improved in about half of the patients so treated. Incapacitating attacks of Ménière''s disease can be successfully treated in selected cases by labyrinthectomy, ultrasound destruction of the vestibular system, or streptomycin treatment. With the advent of the transistor, improved power packs and miniaturization, hearing aids have become more acceptable to patients with sensorineural hearing losses. The most successful procedure for the management of otosclerosis is the stapedectomy operation.     

A three-dimensional finite element model of round window membrane vibration before and after stapedotomy surgery

Piston stapes prostheses are implanted in patients with refractory conductive or mixed hearing loss due to stapes otosclerosis to stimulate the perilymph with varying degrees of success. The overclosure effect described by the majority of researchers affects mainly low and medium frequencies, and a large number of patients report a lack of satisfactory results for frequencies above 2 kHz. The mechanics of perilymph stimulation with the piston have not been studied in a systematic manner. The objective of this study was to assess the influence of stapedotomy surgery on round window membrane vibration and to estimate the postoperative outcomes using the finite element (FE) method. The study hypothesis is that the three-dimensional FE model developed of the human inner ear, which simulates the round window (RW) membrane vibration, can be used to assess the influence of stapedotomy on auditory outcomes achieved after the surgical procedure. An additional objective of the study was to enable the simulation of RW membrane vibration after stapedotomy using a new type of stapes prosthesis currently under investigation at Warsaw University of Technology. A three-dimensional finite element (FE) model of the human inner ear was developed and validated using experimental data. The model was then used to simulate the round window membrane vibration before and after stapedotomy surgery. Functional alterations of the RW membrane vibration were derived from the model and compared with the results of experimental measurements from temporal bones of a human cadaver. Piston stapes prosthesis implantation causes an approximately fivefold (14 dB) lower amplitude of the RW membrane vibrations compared with normal anatomical conditions. A satisfactory agreement between the FE model and the experimental data was found. The new prosthesis caused an increase of 20–30 dB in the RW displacement amplitude compared with the 0.4-mm piston prosthesis. In all frequencies, the FE model predicted a RW displacement curve that was above the experimental curves for the normal ear. The stapedotomy can be well simulated by the FE model to predict the auditory outcomes achieved following this otosurgery procedure. The 3D FE model developed in this study may be used to optimize the geometry of a new type of stapes prosthesis in order to achieve a similar sound transmission through the inner ear as for a normal middle ear. This should provide better auditory outcomes for patients with stapedial otosclerosis.     

Otosclerotic stapedial footplate fixation in an 18th century burial

Fixation of the footplate of the stapes by otosclerosis has been found in the left ear of a probable Spaniard who died about 200 years ago and was buried in the Tucson Presidio. Previous studies on North and South Dakota American Indian crania of about the same time period did not demonstrate any stapedial fixation in 2,600 burials (4,064 temporal bones), 1,416 of which were over 16 years of age at death. The Tucson burial would indicate that this abnormality can be demostrated in old interred skeletal material. Our other studies suggest that this disease process was not common in the prehistoric and historic Indian populations of the Dakotas.     

A second gene for otosclerosis, OTSC2, maps to chromosome 7q34-36

Otosclerosis due to abnormal bone homeostasis of the otic capsule is a frequent cause of hearing loss in adults. Usually, the hearing loss is conductive, resulting from fixation of the stapedial footplate, which prevents normal ossicular vibration in response to sound. An additional type of sensorineural hearing loss may be caused by otosclerotic damage to the cochlea. The etiology of the disease is unknown, and both environmental and genetic factors have been implicated. Autosomal dominant inheritance with reduced penetrance has been proposed, but large families are extremely rare. To elucidate the pathogenesis of the disease, identification of the responsible genes is essential. In this study, we completed linkage analysis in a Belgian family in which otosclerosis segregates as an autosomal dominant disease. After excluding linkage to a known locus on chromosome 15 (OTSC1), we found linkage on chromosome 7q, with a multipoint LOD score of 3.54. Analysis of key recombinant individuals maps this otosclerosis locus (OTSC2) to a 16-cM interval on chromosome 7q34-36 between markers D7S495 and D7S2426.     

Autosomal dominant stapes ankylosis with broad thumbs and toes,hyperopia, and skeletal anomalies is caused by heterozygous nonsense and frameshift mutations in NOG,the gene encoding noggin

Although fixation of the stapes is usually progressive and secondary to otosclerosis, it may present congenitally, with other skeletal manifestations, as an autosomal dominant syndrome-such as proximal symphalangism (SYM1) or multiple-synostoses syndrome (SYNS1), both of which are caused by mutations in NOG, the gene encoding noggin. We describe a family that was ascertained to have nonsyndromic otosclerosis but was subsequently found to have a congenital stapes ankylosis syndrome that included hyperopia, a hemicylindrical nose, broad thumbs and great toes, and other minor skeletal anomalies but lacked symphalangism. A heterozygous nonsense NOG mutation-c.328C-->T (Q110X), predicted to truncate the latter half of the protein-was identified, and a heterozygous insertion in NOG-c.252-253insC, in which the frameshift is predicted to result in 96 novel amino acids before premature truncation-was identified in a previously described second family with a similar phenotype. In contrast to most NOG mutations that have been reported in kindreds with SYM1 and SYNS1, the mutations observed in these families with stapes ankylosis without symphalangism are predicted to disrupt the cysteine-rich C-terminal domain. These clinical and molecular findings suggest that (1) a broader range of conductive hearing-loss phenotypes are associated with NOG mutations than had previously been recognized, (2) patients with sporadic or familial nonsyndromic otosclerosis should be evaluated for mild features of this syndrome, and (3) NOG alterations should be considered in conductive hearing loss with subtle clinical and skeletal features, even in the absence of symphalangism.     

Lack of association between SNP rs3914132 of the RELN gene and otosclerosis in India

Otosclerosis (MIM 166800) is primarily a metabolic bone disorder of the otic capsule, which leads to bony fixation of the stapedial footplate in the oval window; it is among the most common causes of acquired hearing loss. The etiology of this disease is largely unknown, although epidemiological studies suggest the involvement of both genetic and environmental factors. Recently, a reelin gene, SNP rs3914132, located in intron 2, was shown to be associated with otosclerosis in a European population. When we sequenced blood DNA samples of 85 individuals with otosclerosis and 85 controls, four SNPs of this gene: rs3914131 (P = 0.6463), rs3914132 (P = 0.1822), rs9641319 (P = 0.7371), and rs10227303 (P = 0.5669) were not significantly associated with this disease. In one familial case, a novel variant (C/T) at contig position 2923488 was found to be inherited by the proband and affected family members.     

Diverticulitis of the colon; surgical treatment

Appropriate surgical treatment of diverticulitis of the colon can result in a highly satisfactory proportion of permanent cures, with an operative mortality of 2 to 5 per cent. Colostomy is a valuable emergency procedure for the control of severe infection or the relief of obstruction but is not a satisfactory definitive treatment for the cure of diverticulitis. Definitive surgical treatment requires resection of the involved segment of colon. Three indications for surgical intervention in "uncomplicated" diverticulitis are: (1) continued or repeated attacks, (2) persistent deformity as seen by x-ray examination, and (3) persistent blood in the stools. Although a three-stage operation is usually considered a safer procedure, one-stage resections may be safely and satisfactorily employed in many instances.     

DIVERTICULITIS OF THE COLON—Surgical Treatment

Appropriate surgical treatment of diverticulitis of the colon can result in a highly satisfactory proportion of permanent cures, with an operative mortality of 2 to 5 per cent.Colostomy is a valuable emergency procedure for the control of severe infection or the relief of obstruction but is not a satisfactory definitive treatment for the cure of diverticulitis. Definitive surgical treatment requires resection of the involved segment of colon.Three indications for surgical intervention in “uncomplicated” diverticulitis are: (1) continued or repeated attacks, (2) persistent deformity as seen by x-ray examination, and (3) persistent blood in the stools.Although a three-stage operation is usually considered a safer procedure, one-stage resections may be safely and satisfactorily employed in many instances.     

TYMPANOTOMY—Exploratory “Laparotomy” of the Middle Ear

In some cases of conduction deafness or mixed deafness, direct inspection of the area believed to be involved is the only means by which diagnosis can be made with certainty. This can be done by a method of tympanotomy that is used for stapes mobilization. The necessary exposure is done with local anesthesia, is not painful, is well tolerated by the patient and requires only two days in hospital.Reparative procedures may be carried out as indicated.     

NEEDLE BIOPSY OF THE LIVER—General Considerations

Needle biopsy of the liver provides concrete diagnostic information that cannot be as readily obtained in any other way. This report reviews 401 liver biopsies in 312 patients.The major indications for use of this procedure are: To determine the cause of an obscure liver enlargement; to establish the cause of jaundice; to distinguish between malignant disease and cirrhosis of the liver; to determine when hepatitis has subsided; and to evaluate the results of treatment. At times, systemic disease that has not been recognized by other means may be diagnosed by this technique. There is risk in performing this test, and the 0.25 per cent mortality in this series compares favorably with that reported from other clinics. Where the diagnosis by biopsy could be compared with observations at operation or autopsy, the correct diagnosis was made by biopsy in 85 per cent of cases. Greater accuracy was obtained by two or more biopsic examinations in one case then by single biopsy.In several cases in which surgical operation was considered, biopsic information made it unnecessary, and vice versa.     

耳内镜下鼓室成形术治疗慢性化脓性中耳炎鼓膜穿孔的疗效及听力恢复的相关因素分析

摘要 目的：探讨耳内镜下鼓室成形术（TUO）治疗慢性化脓性中耳炎鼓膜穿孔的疗效,并分析影响听力恢复的相关因素。方法：回顾性分析2020年3月~2022年3月期间在邯郸市第一医院接受治疗的218例慢性化脓性中耳炎鼓膜穿孔患者的临床资料。根据手术方式的不同将患者分为A组（n=108,接受传统手术治疗）和B组（n=110,接受TUO治疗）。对比两组疗效、听力恢复情况和并发症发生率。收集B组患者的临床资料,采用多因素Logistic回归模型分析影响听力恢复的相关因素。结果：B组的临床总有效率高于A组（P<0.05）。两组术后6个月气骨导差、骨导听阈、气导听阈下降,且B组低于A组（P<0.05）。两组并发症总发生率组间对比未见差异（P>0.05）。根据听力恢复情况分为良好组（n=75）和不良组（n=35）。单因素分析结果显示,听力恢复与咽鼓管、镫骨情况、鼓室黏膜、人工听骨材料、鼓膜张肌腱、听骨链有关（P<0.05）。多因素Logistic回归模型结果显示：听骨链病变、镫骨仅剩底板、咽鼓管不通畅、人工听骨材料为生物陶瓷、无鼓膜张肌腱是听力恢复的独立危险因素（P<0.05）。结论：TUO治疗慢性化脓性中耳炎鼓膜穿孔,可提高临床治疗效果,改善听力。听骨链病变、镫骨仅剩底板、咽鼓管不通、人工听骨材料为生物陶瓷、无鼓膜张肌腱为听力恢复的危险因素。     

The management abscess of the lung

A review of the literature raises considerable doubt as to the advisability of surgical drainage of lung abscess as a definitive procedure. The mortality rate with use of this procedure and other hazards associated with it, must now be viewed in the light of improved methods of conservative therapy - involving the use of penicillin, bronchoscopic treatment and postural drainage-by which cure can be obtained in more than 80 per cent of cases of acute abscess and in a smaller proportion of cases of chronic abscess. Another factor to be considered is the better chance for diagnosis and effective resection of associated carcinoma when conservative treatment is employed.     

Stapedo-ovalar ankylosis: histomorphologic patterns

This study reports the results of the histo-pathological investigation on the stapes (fragments or complets) of 46 patients (34 females and 12 males) with clinical diagnosis of stapedial otosclerosis and submitted to stapedectomy. Otospongiotic and otosclerotic areas have been found only in some cases; more frequently, erosion cavities filled with fibrous tissue and round-cells infiltration with lymphocytes and/or macrophages have been seen. Osteoclasts were observed only in few cases. Blue mantles have been observed in about half of the cases. Our findings show that non specific chronic inflammation should be more frequent than otospongiosis or otosclerotic foci, and indicate that a phlogosis could be the pathogenetic agent of this disease. This conclusion is in agreement with our previous research, and has been recently confirmed by the observations in stapes of otosclerotic patients of viral antigens and antibodies.     

CHD7 Deficiency in “Looper”, a New Mouse Model of CHARGE Syndrome,Results in Ossicle Malformation,Otosclerosis and Hearing Impairment

CHARGE syndrome is a rare human disorder caused by mutations in the gene encoding chromodomain helicase DNA binding protein 7 (CHD7). Characteristics of CHARGE are varied and include developmental ear and hearing anomalies. Here we report a novel mouse model of CHD7 dysfunction, termed Looper. The Looper strain harbours a nonsense mutation (c.5690C>A, p.S1897X) within the Chd7 gene. Looper mice exhibit many of the clinical features of the human syndrome, consistent with previously reported CHARGE models, including growth retardation, facial asymmetry, vestibular defects, eye anomalies, hyperactivity, ossicle malformation, hearing loss and vestibular dysfunction. Looper mice display an otosclerosis-like fusion of the stapes footplate to the cochlear oval window and blepharoconjunctivitis but not coloboma. Looper mice are hyperactive and have vestibular dysfunction but do not display motor impairment.     

The Role of Radiation Therapy in Myasthenia Gravis

Myasthenia gravis is a serious and debilitating disease associated with conduction defects occurring at the myoneural junction. About 15 per cent of the patients have associated tumors of the thymus and 80 per cent of the remaining patients show abnormalities of the thymus. Although a definite relationship between cause and effect has not been proved, thymectomy or radiotherapy of the thymus does seem to influence the disease.Seven cases of myasthenia gravis in which radiation therapy was used at the University of California Medical Center are reported and compared with those described in the literature. It is concluded that patients whose disease is progressing and not well managed medically, and who have no evidence of thymoma, should be treated by irradiation—whether pre-operatively or as definitive treatment, depending on the result of irradiation. Those patients with evidence of thymoma should be irradiated before surgical procedure. Small tumors, or patients in whom surgical risk is increased, may be managed by radiation therapy alone.     

SUBTOTAL GASTRIC RESECTION—An Appraisal of a Means of Treatment of Benign Peptic Ulceration of the Stomach and Duodenum

In a series of 400 cases of subtotal gastric resection for the treatment of benign ulceration of the stomach and duodenum, the mortality, morbidity and recurrence rate was acceptably low. Fifty-six per cent of the patients had a perfect result, 38 per cent satisfactory, and 6 per cent unsatisfactory. However, the postoperative nutritional status was sufficiently interfered with in a number of patients whose preoperative weight was subnormal that the routine adoption of 75 per cent gastric resection must be questioned. Vagotomy with either pyloroplasty or partial resection may prove to be the most valuable procedure for patients of this type. In properly selected patients, however, gastric resection is a rewarding procedure for both patient and surgeon.     

Subtotal gastric resection; an appraisal of a means of treatment of benign peptic ulceration of the stomach and duodenum

In a series of 400 cases of subtotal gastric resection for the treatment of benign ulceration of the stomach and duodenum, the mortality, morbidity and recurrence rate was acceptably low. Fifty-six per cent of the patients had a perfect result, 38 per cent satisfactory, and 6 per cent unsatisfactory. However, the postoperative nutritional status was sufficiently interfered with in a number of patients whose preoperative weight was subnormal that the routine adoption of 75 per cent gastric resection must be questioned. Vagotomy with either pyloroplasty or partial resection may prove to be the most valuable procedure for patients of this type. In properly selected patients, however, gastric resection is a rewarding procedure for both patient and surgeon.     

Carcinoma of the cervix

Studies by eminent surgeons to reevaluate the place of radical operations in the treatment of carcinoma of the cervix-now that extensive procedures have become less hazardous-apparently have led to confusion in some minds as to choice between surgical and radiation therapy. Pending outcome of the studies, general employment of surgical treatment is unwarranted. Radiation is the treatment of choice in most cases, particularly if the lesion is in an early stage, although radical operation is indicated in certain rare early cases in which delivery of an effective dose of radiation to involved areas is technically difficult. Elsewise it appears at present that operation should be used only in cases of stages III or IV carcinoma-in which results by either means of treatment are poor.One hundred and seven patients were treated with a combination of x-ray and radium irradiation. X-ray was used first to reduce the hazard of implanting the radium. The "five-year arrest" rates were as follows: For 22 patients with stage I lesion, 70 per cent; for 31 with stage II, 55.7 per cent; 33 with stage III, 39.7 per cent; 21 with stage IV, 0. Eighteen patients with diagnosis of carcinoma of the cervix who had had subtotal hysterectomy were treated. The stage of the disease could not be determined. In this group the five-year arrest rate was 52 per cent.