Endolymphatic sac enhancement surgery in elderly patients with Ménière's disease

Ménière's disease is a pathologic condition of the inner ear that is characterized by vertigo, tinnitus and a progressive loss of hearing. When Ménière's disease is unresponsive to medical treatment and when destructive surgery is not advisable, patients, particularly the elderly, often benefit from endolymphatic sac enhancement, a conservative, nondestructive surgical procedure. We evaluated the outcomes of 62 such patients, aged 65 years and older, who underwent a total of 78 endolymphatic sac enhancements. We assessed their response to surgery by means of a questionnaire, which classified pre- and post-surgical data according to criteria established by the American Academy of Otolaryngology-Head and Neck Surgery. Of the 27 patients who returned questionnaires, 23 reported significant alleviation of vertigo symptoms and 19 said their hearing ability had either improved or was maintained at presurgical levels. Endolymphatic sac enhancement resulted in no mortality, and morbidity was documented in only one patient. We conclude that endolymphatic sac enhancement is a safe and viable treatment for elderly patients with Ménière's disease that is refractory to medical therapy.

Expression of glycoconjugates in human eustachian tubes with otitis media

OBJECTIVES

To characterize glycoconjugate expression in normal human eustachian tubes and study the alterations in glycoconjugate expression found in eustachian tubes with otitis media.

STUDY DESIGN

Using lectin histochemistry, alterations in glycoconjugates were studied in three normal temporal bones, in four temporal bones with mucoid otitis media (MOM), and in five with serous otitis media (SOM).

METHODS

Sections of previously processed temporal bones were decelloidinized, and then incubated with seven biotinylated lectins--WGA, SNA, MAA, BPA, PNA, UEA-1, and LcH--that reflect seven carbohydrate residues of glycoconjugates, respectively: GlcNAc/NeuNAc, NeuNAc alpha(2-6)GalNAc, NeuNAc alpha(2-3)GalNAc, Gal beta(1-3) GalNAc, L-fucose, and alpha-mannose residues. Control sections were incubated with inhibitory carbohydrates or without biotinylated lectins.

RESULTS

In the normal temporal bones, five carbohydrate residues in goblet cells and cilia of the eustachian tube demonstrated moderate to strong activity--NeuNAc alpha(2-6)GalNAc, NeuNAc alpha(2-3)GalNAc, GalNAc, Gal beta(1-3)GalNAc, and L-fucose. Two residues demonstrated weak activity--GlcNAc/NeuNAc and alpha-mannose. Temporal bones with MOM revealed increases in sialic acid and alpha-mannose, and a decrease in L-fucose. Residues of carbohydrates in the cilia of bones with SOM were notably decreased, especially for GalNAc, Gal beta(1-3)GalNAc, and NeuNAc alpha(2-6)GalNAc.

CONCLUSIONS

Glycoconjugates in the normal human eustachian tube are rich in GalNAc, Gal beta(1-3)GalNAc, L-fucose, and NeuNAc alpha(2-3/2-6) GalNAc, but low in alpha-mannose and sialic acid. Eustachian tubes from cases with SOM or MOM demonstrated alterations in glycoconjugate expression in cilia and goblet cells, which may reflect disorder of the carbohydrate metabolism during otitis media, especially in SOM.

Silent intratympanic membrane cholesteatoma

OBJECTIVE

To detect the presence of intratympanic membrane cholesteatoma in cases of chronic otitis media.

DESIGN

Two hundred forty-three temporal bones from patients with chronic otitis media were studied for the presence of intratympanic membrane cholesteatoma.

METHODS

Specimens had been previously removed at autopsy, fixed in 10% buffered formalin, decalcified in trichloroacetic acid, dehydrated in a graded series of ethanol, and embedded in celloidin. Sections were cut at a thickness of 20 microm, stained with hematoxylin eosin, and examined using light microscopy.

RESULTS

Intratympanic membrane cholesteatomas were found in five of the 243 temporal bones with chronic otitis media. All temporal bones with intratympanic membrane cholesteatomas were from adult patients. Two patients had bilateral intratympanic cholesteatomas in symmetric quadrants of the tympanic membrane, and the remaining patients with unilateral intratympanic membrane cholesteatoma had been operated on previously for a cholesteatoma of the opposite ear. Other common findings included chronic granulation tissue in the middle ears and mastoids, ossicular pathologic conditions, and in four of the five ears, fluid in the middle ears and/or mastoids.

CONCLUSION

When a white area is observed on the tympanic membrane of patients (especially those with "silent" chronic otitis media), differential diagnosis should include not only tympanosclerosis, but also intratympanic membrane cholesteatoma.

[Silence nature of otitis media]

To explore the silence nature of otitis media, the temporal bone slides from 306 ear with various types of otitis media were studied histopathologically under the light microscopy and their case histories were reviewed at the Otopathology Laboratory, the University of Minnesota Otitis Media Research Center U.S.A. The results showed that 80.97% of otitis media cases lacked clinical symptoms in pathologic process. The subnormal function status of the eustachian tube and the low-degree infection in pathologic process of otitis media probably are basic causes of silence nature of otitis media. The anatomic specialty of ventilation/drainage system of middle ear cleft and the inflammatory pathologic change causing obstruction of internal ventilation/drainage system and leading to the retention of effusion in posterior areas of middle ear cleft may be are important factors for the development of obstinate pathologic change and silence nature of pathologic process of chronic otitis media.

Histopathology of human temporal bone after cis-platinum, radiation, or both

Preserving organs by use of multiple modalities has become protocol in treating squamous cell carcinomas of the head and neck, but cis-platinum and radiation can impair hearing. To determine the effect of cis-platinum, radiation, or a combination of these treatments on the temporal bone, we studied histopathologic slides of 15 human temporal bones: four after cis-platinum, five after radiation, two after combined treatment, and four from normal controls. Hair cells and cells in spiral ganglia were counted in reconstructed organs of Corti. Lumen-to-diameter indexes in arterioles near facial nerves were quantified for four normal controls and seven irradiated patients. Available audiograms were compared. Decreased spiral ganglion cells, loss of inner and outer hair cells, and atrophy of stria vascularis were demonstrated in groups receiving cis-platinum, radiation, and combinations, compared with age-matched controls. Arterioles around facial nerves demonstrated fibrinous clots within the intima, endothelial proliferation, and hypertrophy and fibrosis of vascular walls in smooth muscle. Fibrosis in connective tissue was clearly progressive after radiation. Cis-platinum and radiation can contribute to otologic sequelae, including sensorineural hearing losses, vascular changes, serous effusion, or fibrosis. Prophylactic treatments and techniques to deliver them should be considered for protection of temporal bones and preservation of hearing after oncologic modalities.

Clinical-histopathological correlations of pitfalls in middle ear surgery

Significant anatomical variations within the middle ear are described as well as atypical histopathological findings in 13 selected human temporal bones. Bones studied included such vascular and bony abnormalities as carotid artery canal dehiscence, a high jugular bulb, persistent stapedial artery and facial nerve canal dehiscences. Bones also included obliterative otosclerosis, malleus head fixation and a variety of chronic inflammatory changes and/or sequelae. Those features considered to render cases prone to complications are detailed.

Loss of spiral ganglion cells as primary manifestation of aminoglycoside ototoxicity

Although pulmonary infections caused by Pseudomonas aeruginosa can hardly be eradicated in patients with cystic fibrosis (CF, the most common genetic disease among Caucasians), these patients are mainly treated with intravenous and nebulized tobramycin. Long-term treatment with tobramycin, however, may induce ototoxic effects. We assessed the clinical histories and postmortem temporal bones of six patients with CF for signs of this ototoxicity. Four bones showed typical manifestations of ototoxicity induced by aminoglycosides (AGs): loss of hair cells in the lower turns, and degeneration of ganglion cells. Six bones revealed no loss or scattered loss of hair cells, however, degeneration of the spiral ganglion cells was observed. This suggests that degeneration of the spiral ganglion may occur as a primary manifestation in some cases of ototoxicity due to aminoglycosides. Recent reports have shown that trophic factors (neurotrophins and acidic fibroblast growth factor) interacting with hair cells and the spiral ganglion protect the inner ear from damage. It may be that disturbances in supply of such trophic factors caused degeneration of ganglion cells without loss of hair cells in the cases we studied.

Autoimmune sensorineural hearing loss: a human temporal bone study

PURPOSE

To describe histopathologic findings in temporal bones of a patient whose clinical history suggests a sensorineural hearing loss (SNHL) of autoimmune origin.

MATERIALS AND METHODS

Temporal bones from a patient with a history of ulcerative colitis, leukemia, and SNHL were examined by light microscopy.

RESULTS

Histopathologic findings included: (1) organs of Corti missing or absent in all cochlear turns; (2) cells decreased in spiral ganglia, and lymphocytic infiltration; (3) absence of portions of the spiral prominence; (4) endolymphatic hydrops in basal, middle, and apical cochlear turns and in the saccule and utricle; (5) fibrosis and osteoneogenesis of a scala tympani of the basal turn of the cochlea, the posterior semicircular canal, and the canal of Cotugno; (6) fibrosis of the vestibular aqueduct and endolymphatic sac; and (7) lymphocytes in the endolymphatic sac, perisaccular area, inferior cochlear vein, and Rosenthal's canal.

CONCLUSION

Histopathologic findings in the temporal bones of this patient with ulcerative colitis, sensorineural hearing loss, and vestibular symptoms closely parallel those in a previously reported animal study of autoimmunity and suggest the possibility of a SNHL of autoimmune origin.

Significance of epidermoid formations in the middle ear in fetuses and children

OBJECTIVE

To determine the incidence, size, and location of epidermoid formations (EFs), which have been suggested to be precursors of congenital cholesteatomas, in temporal bones from fetuses and children.

DESIGN

We examined temporal bones from 226 fetuses and children up to the age of 10 years for the incidence, size, and location of EFs.

RESULTS

Twenty-five EFs were identified in middle ears of 3 fetuses, 7 neonates, 9 infants, and 2 children aged 2 and 3 years. There was a male-female preponderance of 5:4. Generally, we saw EFs between the anterosuperior edge of the eardrum and the anterior limb of the tympanic ring, but 4 were below the level of the handle of the malleus. Their widths ranged from 25 to 300 microns. Keratinization was not observed in any EF. Contrary to previous reports, we found EFs not only in ears of fetuses, but also in ears of infants and children.

CONCLUSION

Although EFs may persist in some ears, possibly developing into congenital cholesteatomas, our findings do not provide direct support for this concept.

A new adhesive bonding material for the cementation of implantable devices in otologic surgery

BACKGROUND

Presently, there are no U.S. Food and Drug Administration (FDA)-approved adhesive bone cements for the surgical fixation of prosthetic materials in the middle ear. A promising new cement, 4-META/MMA-TBB opaque resin, has shown remarkable adhesive properties as a bone cement in vivo. The cement is composed of 4-methacryloyloxyethyl trimellitate anhydride (4-META) and methyl methacrylate (MMA) as monomers and tri-n-butyl borane (TBB) as an initiator.

METHODS

An electromagnetic semiimplantable hearing device presently under development was implanted into the middle ear of six cats using 4-META/MMA-TBB resin to cement a titanium-encased magnet to the incus. The animals were subsequently killed (at a mean of 9.6 months) to assess the (temporal bones and specifically the magnet-incus complex in each animal.

RESULTS

The titanium-encapsulated magnet was firmly adherent to all incuses without any failure of the cement-bone interface. Histopathologic examination of the implanted temporal bones demonstrated lack of middle ear inflammation. Transmission electron microscopy of the incuses demonstrated a unique "hybrid layer" in the bone-side subsurface of the bone-cement interface that elucidates the mechanism of interfacial adhesion.

CONCLUSIONS

Our investigation highlights the special biomechanical properties as well as the biocompatibility of 4-META/ MMA-TBB resin that make it an attractive bone-bonding agent for use in otologic surgery, including its potential usefulness during ossicular reconstruction.

Outgrowing schwannomas arising from tympanic segments of the facial nerve

PURPOSE

Although there have been numerous reports of clinical cases of facial nerve schwannoma, histopathologic studies of its early stages of development are rare. The purpose of this study was to describe the incidence, origin, and pathology of small, asymptomatic schwannomas of the facial nerve.

MATERIALS AND METHODS

Fifteen hundred twenty-six ears from the human temporal bone collection of the Otitis Media Research Center Otopathology Laboratory at the University of Minnesota were studied under light microscopy.

RESULTS

Twelve bones with morphologic indications of type A Antoni tissue that mimics facial schwannoma in the tympanic cavity were selected. The 12 ears were from nine individuals with asymptomatic histories. The twelve schwannomas developed from perineurium at dehiscences in the facial canal near the oval window, forming defects in the epineurium by growth of Schwann cells downward and outward toward the stapes. No obvious compressions or lesions within fibers in the facial nerve were observed.

CONCLUSION

Because these tumors grow slowly without hearing loss or facial nerve symptoms, they may be mistaken for granulation tissue during surgery for chronic otitis media.

Residual mesenchyme in temporal bones of children

The role of mesenchyme in the temporal bone is still poorly understood. A microscopic study of residual mesenchyme was undertaken in temporal bones of children from birth to 5 years of age. Residual mesenchyme was found to be located in the mastoid antrum and epitympanum more often than in the mesotympanum. The amount of mesenchymal tissue remaining in the temporal bones decreased with increasing age. Persistence of mesenchyme in the temporal bone was related to congenital morphologic ear anomalies and syndromes. There was also an association evident with pulmonary disease, but not with congenital heart defects. Persistent mesenchyme was also found to be significantly associated with chronic middle ear inflammation, and in cases of unilateral otitis media the ear with otitis media had more residual mesenchyme than the non-otitis media ear.

Temporal bone study of Down's syndrome

OBJECTIVE

To study temporal bone histopathologic characteristics of the inner ear and middle ear cleft of patients with Down's syndrome.

DESIGN

Sixteen temporal bones from eight patients with Down's syndrome were studied. Ten temporal bones from subjects without pathologic ear lesions but with congenital heart disease served as controls. The two-dimensional graphic reconstruction method proposed by Guild and modified by Schuknecht was used to study the cochleas; measurement of the vestibules was based on Igarashi's method.

SETTING

The temporal bone collection of the Otitis Media Research Center, Department of Otolaryngology, University of Minnesota School of Medicine, Minneapolis.

RESULTS

Six bones showed short cochlea, and four of six had Mondini's cochlea. The overall cochlear lengths in this study group were notably shorter than those of the controls. The spiral ganglion cell population and two of three vestibular dimensions also were notably less than the controls. Middle ear findings included residual mesenchyme, stapes abnormality, otitis media, and large facial canal dehiscence.

CONCLUSIONS

The difficulties encountered in rehabilitation of patients with Down's syndrome caused by mental retardation can be compounded by the hearing loss caused by middle and inner ear abnormalities. A complete evaluation of hearing loss and therapy before starting the rehabilitation gives the most favorable outcome.

Developmental anatomy of the supratubal recess in temporal bones from fetuses and children

The supratubal recess (STR), located superior to the bony eustachian tube and anterior to the attic and often the site of disease, is clearly separated from the attic by the presence of a bony partition. Its anatomic development in childhood, however, remains nuclear. We reviewed serial horizontal sections of fetal and children's temporal bones from the collection of the Otopathology Laboratory, University of Minnesota. Apparently, upward expansion of the bony eustachian tube begins at a late fetal stage and continues throughout childhood, thus forming the STR. Our finding that the STR had already developed in temporal bones without pneumatization of petrous bone suggests that its formation is independent of the air-cell system. Absorption of mesenchymal tissue in the STR tends to be slower than elsewhere in the temporal bone. Surrounded solely by petrous bone, the STR seems, both developmentally and anatomically, a distinctive compartment of the middle ear.

Audiological profiles and Menière's disease

Pure-tone audiograms of 501 patients with preoperative Menière's disease were analyzed. Age of onset and incidence of bilaterality were studied. The most common audiogram was the peak-type (50.26%), next the falling-type (26.26%), and then the dip-type (9.24%). Although few papers mention this peak audiogram, we suggest it is a diagnostic feature of Menière's disease. Average age of onset was 42.59 years; this did not differ from males to females. Prevalence in females exceeded that in males by about 4:3. The disease was bilateral in 31.13%. Generally, those with better hearing thresholds at the first examination had less tendency to develop bilaterality. Age of onset was not significantly correlated with bilaterality.

Normal and metastatic melanin in the temporal bone

PURPOSE

Malignant melanoma is known to metastasize to the temporal bone. However, melanocytes exist in the normal inner ear and may be difficult to distinguish from metastatic melanotic cells. This study describes distribution of normal melanin in the ear and metastatic melanoma to the temporal bone.

MATERIALS AND METHODS

Normal melanin distribution is described in 48 temporal bones from White (18), Native-American (19), and African-American (11) individuals and metastatic melanoma to the temporal bone is described in four cases (seven temporal bones). Temporal bones were removed at autopsy, fixed in 10% buffered formalin, and processed for routine celloidin embedding. Sections were cut at a thickness of 20 microns and every tenth section was stained with hematoxylin-eosin for light microscopic evaluation.

RESULTS

Normal melanin was found in the inner ear, mainly around terminal neural structures and blood vessels, and occurred in greater quantities in African-American individuals. Metastatic melanotic cells reached the temporal bone by hematological dissemination, and by neural invasion from the central nervous system. No correlation was found between histopathological findings and clinical symptoms of patients.

CONCLUSIONS

Metastatic melanoma to the temporal bone may be seen in the same areas as normal melanin. They may also be observed in bone marrow cells of the petrous bone and along the course of nerves of the internal auditory canal and cochlear vestibular labyrinth, either by following neural sheaths or blood vessels that run along the nerve. Metastatic disease to the temporal bone is often asymptomatic, or it may present with uncharacteristic symptoms that may delay diagnosis.

Otitis media (silent): a potential cause of childhood meningitis

Sixteen temporal bones from 8 infants with otitis media, who died of meningitis, and 6 controls from infants with only otitis media, were studied histologically. All bones contained middle ear effusion and residual mesenchyme, but, unlike the controls, the meningitic cases showed considerable histopathological tissue changes of chronic and acute otitis media and chronic inflammatory cells in the round window membrane and within the perilymph, the modiolus, and the cochlear aqueduct, suggesting the latter as likely portals from the inner ear to the meninges. Since all tympanic membranes were intact and 3 were histologically normal, this silent route of infection warrants medical vigilance.

Micropathologic changes of pars tensa in children with otitis media with effusion

Clinical studies have supported a relationship between otitis media with effusion in children and chronic otitis media in adults. Although clinical studies are numerous, relatively little is known about the histopathologic changes of the tympanic membrane in otitis media with effusion. Tympanic membranes were taken from the intermediate zone of the anteroinferior quadrant of the tympanic membrane during surgery for placement of tympanostomy tubes in 30 children (age range, 4 to 10 years) who did not show any improvement after 3 months of conservative treatment for otitis media with effusion. Control specimens were taken from normal temporal bones at autopsy. All specimens were observed with light and electron microscopy. Histologic degeneration of the tympanic membrane of patients with otitis media with effusion occurred most often in the lamina propria and the submucosal layer. There was an increase in the thickness of the tympanic membrane as a result of edema and fibrosis of the submucosal layer. A decrease in the thickness of the outer and inner fibrous layers occurred in the lamina propria. The histopathologic changes observed in the lamina propria may result in a change in the elastic properties of the tympanic membrane.

The temporal bone in multiple myeloma

Multiple myeloma is a malignant disease of the skeleton. Anatomically, any bone may ultimately come to be involved in a given case. In a literature review, no published series of temporal bone findings have been reported. In this study, oto-histopathologic changes associated with multiple myeloma are analyzed and reported in 15 temporal bones from 8 patients. The bone marrow of 13 temporal bones was involved by the tumor. Osteolysis was evident in 11 temporal bones. Serous otitis media (SOM) or purulent otitis media (POM) was seen in 13 ears with 12 showing mastoid effusions. Eight ears exhibited pathological changes in inner ears, including degeneration of the organ of Corti, atrophy of stria vascularis, decreased ganglion cells, and labyrinthine hydrops. The inner ear changes were most severe in 2 patients who had otologic symptoms. Infiltration of myeloma cells was not apparent in the middle ear mucosa or the inner ears.

Prevalence of microfissures in the human temporal bone: a report of 1000 temporal bones

A total of 1000 human temporal bones were studied to determine the prevalence of two microfissures: 1. the one between the facial canal and the vestibule, 2. the microfissure between the round window niche (RWN) and the posterior semicircular canal (PSC). Additionally, this study compares the prevalence according to temporal bone age and sex. The microfissure between the facial canal and the vestibule was observed in 470 (47%) temporal bones, with a bilateral presence of 77.2%. The prevalence of this microfissure increases linearly with age. It was not found in any bone within the 0 to 2 age group. It was present in 3 (7.3%) bones from the 2 to 9 age group, as opposed to 374 (54.8%) bones from the 40 and over group. The microfissure between the RWN and the PSC was detected in 915 (91.5%) temporal bones. This second microfissure was found to be an overwhelmingly bilateral entity. The prevalence of this other microfissure also increases with age. This microfissure was also not present in any temporal bone within the 0 to 2 age group. It was found in 28 (68.3%) bones from the 2 to 9 age group, in contrast to 678 (99.4%) temporal bones from the 40+ group.

New developments in treating otitis media

Treatment of otitis media has changed over time as the disease has become better understood and as clinical experience and technology have expanded and grown. Successful treatment depends on accurate definitions and classifications of types of otitis media. An awareness of the pathogenic and pathologic correlates of otitis media enhances accurate diagnosis and improves the results of treatment. An understanding of the otitis media continuum also assists in management. On the basis of studies largely emanating from the University of Minnesota's Otitis Media Pathogenesis Research Program, we here highlight definitions, classifications, and diagnosis of the otitis medias, and medical treatments of these various clinical and pathologic entities and their sequelae.

Surgical advances in treating otitis media

Surgical methods of treating otitis media and its sequelae are discussed, according to the classification of otitis media presented in an earlier report. Surgical management of otitis media with effusion and recurrent purulent otitis media includes myringotomy and use of ventilation tubes. Occasionally, otitis media with effusion will lead to structural and other pathologic changes in the middle ear, and conservative treatments such as use of medication or tubes will not suffice. Indications and methods for exploratory tympanotomy and reconstruction of the middle ear are discussed. In such instances, tympanoplasty can be used to the patient's benefit. Chronic otitis media with mastoiditis, defined by the presence of intractable pathologic tissue, generally requires surgical correction. Classic methods include simple mastoidectomy, modified radical (Bondy) mastoidectomy, and radical mastoidectomy. Current classifications of procedures would also include closed-cavity tympanomastoidectomy, open-cavity tympanomastoidectomy, and intact-bridge tympanomastoidectomy (a combined approach). The diagnostic and surgical approach to silent or subclinical otitis media is discussed. Diagnosis and treatment of sequelae of otitis media, including sequelae in the middle ear and, less commonly, in the inner ear, are discussed.

Prevalence of carotid canal dehiscence in the human middle ear: a report of 1000 temporal bones

A total of 1000 human temporal bones were used to study the prevalence of carotid canal dehiscence, microdehiscence, and thin bony coverage. Additionally, this study compares the prevalence according to sex and temporal bone age. A carotid canal dehiscence was detected in 77 (7.7%) bones. It was present bilaterally in 23.2% of the paired temporal bones. The prevalence of carotid canal dehiscence decreases with increasing temporal bone age. It was found in 10 (15.9%) bones in the younger than 2 age group, as opposed to 43 (6.3%) bones from the 40 and older group. The concept of microdehiscence of the carotid canal is introduced. A carotid canal microdehiscence was found in 74 (7.4%) bones. Microdehiscences were noted to occur bilaterally in 12.3% of the paired bones. The prevalence of carotid canal microdehiscence also decreases with increasing temporal bone age. It was detected in 7 (11.1%) bones in the younger than 2 age group, in contrast to 51 (7.5%) bones in the 40 and older group. A total of 134 (15.5%) temporal bones were found to have a thin bony coverage, without the presence of a dehiscence or microdehiscence. The prevalence of thin coverage was noted to increase linearly with age. A thin carotid canal was found in 2 (8.3%) bones from the younger than 2 age group, whereas 113 (17.3%) temporal bones from the 40 and older group exhibited this entity. To the best of our knowledge, this is the first systematic study of histologic sections of a large number of temporal bones that looks at these entities.