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In the present structural study the authors investigated the border of permanent tympanic membrane (TM) perforations in patients selected for myringoplasty. Furthermore, a panel of monoclonal antibody markers that recognize different epitopes within glycosaminoglycans as well as antibodies to epidermal growth factor and fibronectin were applied to the sections. In half of the specimens the epithelial junction ended at the inside of the perforation border, whereas in the other half it was located at the perforation border itself. In the junctional area the keratinocytes were covered by a thick keratin layer which protruded as a spur centripetally in order to bridge the perforation. Epidermal cells formed papillae and contained remnants of keratinocyte nuclei that showed similarities to those of the skin in inflammatory conditions. The connective tissue layer was fibrous and showed areas containing sclerotic plaques. The inner epithelium of the TM had abundant ciliae, thus supporting the concept that cells of the mucosal lining of the TM are able to differentiate in inflammatory conditions into ciliated cells and secretory cells. The immunoreactivity of hyaluronan and other glycosaminoglycans, the immunoreactivity of epidermal growth factor, and immunoreactivity of fibronectin, all of which are known to occur in healing wounds, were only scantily demonstrated; this could be one reason for the arrested healing and a reason why the natural drive to complete a mature closure is abandoned. [ABSTRACT FROM AUTHOR]

Stapedectomy and stapedotomy are the techniques currently used in the surgical treatment of otosclerosis. During the period 1977-81, a total of 60 consecutive patients were subjected to surgery for otosclerosis according to the method of Schuknecht (Gelfoam and wire prosthesis). Another 55 consecutive otosclerotic patients were operated on during 1987-91with stapedotomy, according to the method advocated by Fisch (Fisch-type piston). Independent of the surgical technique used, the maximal hearing gain was obtained 1 year after surgery. In the frequency range 0.5-3 kHz, the mean value of the averaged pure tone thresholds improved from 52 to 28 dB in the stapedectomy group and from 57 to 26 dB in the stapedotomy group. In the frequency range 4-6 kHz, the subjects' hearing was not significantly improved in the stapedectomy group, whereas the subjects' hearing in the stapedotomy group improved from 61 to 44 dB. Per- and postoperative complications were low in both groups, except for one patient in the stapedectomy group who experienced the serious complication of a deaf ear after surgery.

Antimicrobial agents have greatly reduced the incidence of intracranial complications of infections of the middle ear and mastoid. Too many prescriptions and overconsumption of antibiotics when otitis media is suspected has caused resistance to many antibiotics, leading to a pronounced and justifiable desire to reduce the widespread excessive use of antibiotics. The possible untoward consequences of a too restricted antibiotic policy, however, is illustrated by the following case of a 14-year-old boy who, after non-treatment of an ear infection, fell ill with one-sided headache and vomiting caused by a lateral sinus thrombosis. After intravenous treatment with antibiotics, anticoagulants and ventilation of the middle ear, the infection was cured without complications. This case calls attention to the symptoms of otitic complications arising outside the temporal bone. The physician must always bear in mind the possibility of an unusual event. The general treatment of endocranial complications is outlined, giving details of the treatment given in this special case. We stress that one should not be too cautious in prescribing antibiotics in otitis media.

Thirty consecutive patients with permanent perforations of their tympanic membranes (TM) present from 2.5 to 50 years (mean 18.7 years) were admitted to a prospective study using two alternative methods of dressings for closure of the perforations. An adhesive-coated hydrocolloid material was compared with a conventional dressing of vaseline impregnated rice paper patch after de-epithelialization of the perforation border. Nine of the permanent TM perforations (30 per cent), five with the hydrocolloidal dressing and four with the rice paper patch had healed when followed-up after one year. The size of eight of the central perforations that had healed was equal to or less than 25 per cent of the TM. Also one perforation with a size of 65 per cent had healed. Seven perforations were located in the posterior part of the TM: four in the posterior-superior quadrant, one in the inferior quadrant, one had engulfed the posterior half of the TM and one included the anterior-inferior quadrant. Only two perforations out of 14, with a size of 25 per cent or less, located in the anterior-inferior quadrant, healed. No significant difference was demonstrated between the two types of dressings. Both groups noted an immediate improvement in hearing of 10.8 and 9.3 dB, respectively, after application of the dressing. The study demonstrates that application of an occlusive dressing or paper patch in 30 per cent of patients can promote the healing of long-standing perforations. The chances for healing are better if the perforation is located in the posterior part of the TM. This simple technique immediately improved hearing and should be tried before a patient is referred for myringoplasty surgery.

Topically applied hydrocortisone was used to develop an animal model for persistent tympanic membrane (TM) perforations. Hydrocortisone suspension was applied on the margins of TM perforations of standardized size in rats once daily for 10 days. The healing patterns of the TMs were mapped weekly and, when the perforations were about to close, daily. After 50 days, all hydrocortisone-treated perforations were open, whereas the controls closed within 9 to 12 days. At 3 months, when one third of the perforations still were open, the TMs were studied by otomicroscopy and light microscopy. All TMs were thickened and covered by keratin and wax. The thickened epidermal layer at the border of the TM perforations that remained open also draped the surface of the perforation facing the middle ear cavity. The thickened connective tissue layer contained abundant fibroblasts with their axes of length oriented at random. Both application of 1.4% hyaluronan and wounding of the perforation border enhanced the healing rate of the hydrocortisone-induced chronic TM perforation.

Purpose: The sequela of a temporal bone fracture include hearing loss, vestibular dysfunction, and facial nerve injury. A large series of patients with temporal bone fractures are reviewed to correlate mechanism of injury, fracture location, and outcome., Patients and Methods: A retrospective analysis of patients evaluated between 1978 and 1987 for temporal bone fractures at two Swedish clinics was undertaken. Assessment of auditory, vestibular, and facial nerve function is reported. Follow up varied from 3 months to 12 years., Results: A total of 72 temporal bone fractures were encountered. Eleven patients had chain incongruencies, nine of whom were operated on with resultant good hearing. Transverse fractures were associated with severe sensorineural hearing loss while longitudinal fractures frequently were accompanied by ossicular disruption and persistent conductive hearing loss. Patients with vertigo or dizziness frequently had a good prognosis. Facial nerve injury occurred in 14 patients, eight of whom recovered., Conclusions: Hearing loss following temporal bone fracture reflects the site and mechanism of injury. Transient conductive hearing loss may be due to blood in the middle ear, perforation of the tympanic membrane, or injury to the ossicular chain. Conductive loss persisting 6 to 7 weeks after trauma and exceeding 30 dB is an indication for surgical exploration.

In a rat study, an occlusive double-layer transparent hydrocolloid dressing, Duo-DERM, was compared with a rice paper dressing in the treatment of tympanic membrane perforation. The Duo-DERM dressing manifested better healing properties, and the healed membrane was histologically similar to spontaneously healed membrane, being generally thin with moderate connective tissue thickening. If this dressing is found to have good healing properties in clinical trials, it would mean a great saving in health care resources. The method is simple, inexpensive, and gives immediate improvement in hearing.

Ototopical drugs such as antiseptics, antibiotics and solvents can have an ototoxic potential. These substances are often combined with an anti-inflammatory steroid of which hydrocortisone is one of the most commonly used. Little is known of possible adverse effects on the inner ear of hydrocortisone. From animal experiments it has been shown that this drug applied in the round window niche will impair the ABR thresholds in the high frequency range. The ototoxic potential of glucocorticoids will be discussed and questioned.

It is known that the healing of a perforated tympanic membrane can be influenced by mechanical procedures as well as drugs. Animal experiments have recently shown that local treatment with steroids delays the healing of a tympanic membrane perforation, whereas hyaluronan (hyaluronic acid) improves the healing rate as well as the quality of the scar. Hyaluronan, a non-sulphated glycosaminoglycan, belongs to the extracellular matrix substances. In the present study another glycosaminoglycan--heparin--was applied on experimental tympanic membrane perforations. This report confirmed that also this extracellular matrix substance improves the healing rate of a tympanic membrane perforation and the scar quality.

The present study focused on structural changes of the round window membrane (RWM) from agents that evoke transient or permanent impairment of the auditory brainstem response when applied into the RW niche. Escherichia coli (E. coli) lipopolysaccharide (LPS) in sterile water (SW) and a 2% suspension of hydrocortisone (CORT), micronized in SW, were instilled into the round window (RW) niche of Sprague-Dawley rats. The morphology of the RWM was analyzed 3 to 21 days after instillation of either substance. Both substances caused minor structural alterations at the light microscopic level. The RWM showed a slight thickening and an invasion of inflammatory cells. At the ultrastructural level, the CORT-treated specimens showed an increased epithelial height and numerous microvilli, whereas the epithelium of the LPS-treated specimens was extended and contained few microvilli resembling those in the normal RWM. We postulate that the RWM may undergo dynamic structural changes when exposed to various agents. The structural alterations per se can influence the passage of substances from the middle ear to the inner ear.

The effects of topically applied hydrocortisone on experimental tympanic membrane (TM) perforations in rats were evaluated by otomicroscopy and light microscopy. Standardized TM perforations, occupying the whole upper rear quadrant, were performed, and a 2% hydrocortisone suspension (CORT) was applied once daily for 10 consecutive days. Application of CORT caused a delayed healing pattern, and even at 1 month only 2 of 12 perforations had healed. The keratinizing squamous epithelial cells of the TM appeared hypertrophic, whereas hyperplasia, characterizing a nontreated healing TM perforation, was less prominent. The connective tissue layer of the CORT-treated TM was invaded by abundant inflammatory cells, mainly polymorphonuclear leukocytes. Also, when applied to an intact TM, CORT caused hypertrophy of the epidermal cells and an inflammatory reaction within the TM.

Inner ear function was assessed by a frequency-specific (+/-100 Hz) auditory brainstem response (ABR) technique after a single instillation of a suspension of purified E. coli lipopolysaccharide in sterile water into the round window (RW) niche in rats. Instillation of endotoxin caused a transient concentration and tonotopically dependent dysfunction of the inner ear. The largest threshold impairment occurred in the high-frequency region anatomically located close to the RW. At 31.5 kHz the threshold impairment persisted throughout the study. Morphologic damage to the inner ear was not detected at the light microscopic level when using serial sections from decalcified specimens. Our study supports the clinical hypothesis that remnants of non-viable bacteria such as endotoxins, when trapped in the middle ear, can promote middle ear effusion and dysfunction of the inner ear.

The effect of cortisone on the inner ear function was investigated. A suspension of 2% hydrocortisone in sterile water was instilled into the middle ear in the round window niche area of healthy rats. The hearing for eight frequencies was determined by auditory brainstem response (ABR) measurements. After 5 days of daily local application, ABR thresholds impaired in the high-frequency range 12 to 31.5 kHz. The impaired ABR thresholds remained unchanged throughout 3 weeks of observation, indicating irreversible damage to the inner ear. It is also noteworthy that hydrocortisone delayed healing of the perforated tympanic membrane.

The ototoxicity of 50% propylene glycol, 70% isopropyl alcohol, 2% acetic acid, Otic Domeboro solution (Miles Pharmaceuticals, West Haven, CT), 1% Gentian violet (Purepac Pharmaceutical, Elizabeth, NJ), Vosol Otic solution (Wallace Laboratories, Cranbury, NJ), Genoptic Ophthalmic solution (Allergan Pharmaceuticals, Irvine, CA), Cortisporin Otic suspension (Burroughs Wellcome, Greenville, NC), Coly-Mycin S Otic (Parke-Davis, Rochester, MI), and Pyocidin Otic (Berlex Laboratories, Cedar Knolls, NJ) was studied in rats according to their effect on the latencies of the second peak of the auditory brainstem responses (ABR) at different sound pressure levels. The substances were instilled into the round window (RW) niches of rats, and the ABR to 1-kHz and 6-kHz tonebursts were obtained, 30 minutes, two hours, and 1 week after exposure. For all substances except isopropyl alcohol and propylene glycol, which evidently quickly penetrated the RW, approximately two hours of exposure were required before inner ear function was affected. The ototoxic effect of the antibiotic drugs was to some degree reversed with time, whereas the recorded potentials for antiseptics such as 1% Gentian violet, 2% acetic acid, and Otic Domeboro indicate that they caused severe damage to inner ear function. Some increases in latencies were also noted after exposure to propylene glycol and isopropyl alcohol, except when the latter was quickly withdrawn from the RW niche.

The effects on inner ear of Xylocain, EMLA, phenol, endotoxin and hydrocortisone were analysed before treatment and 24 h-6 months after instillation of each drug into the round window (RW) niche, where the substance was left. Inner ear function was determined by repeated auditory brainstem recordings (ABR). All cochleae were analysed morphologically at the light microscopic level. Hydrocortisone, Xylocain and endotoxin caused functional changes without morphological correlates, even at long-term follow-up. In contrast, phenol and EMLA caused both functional impairment and graded morphological damage to the organ of Corti in the basal coil. Outer hair cells (OHC) were more vulnerable than inner hair cells (IHC).