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Fluorescein angiography is a recently developed method of studying the tympanic membrane's dynamic vasculature. Our preliminary studies using an ophthalmic fundus camera and aural speculum did not always permit visualization of the entire tympanic membrane, and the electronic flash unit used in our initial studies did not cycle fast enough to visualize effectively the rapid arterial phase of blood flow. In this report, we describe an endoscopic method of tympanic membrane fluorescein angiography that uses a continuous xenon light source. A representative angiogram from a normal subject is described. The mallear artery apparently is the major blood supply to the posterior half of the tympanic membrane, which is consistently better perfused than the anterior half. Branches from the annular ring of blood vessels supply the anterior half of the tympanic membrane. Preliminary studies of two temporalis fascia tympanoplasty patients indicate that the graft becomes revascularized 2 to 4 weeks after surgery and that posterior grafts may revascularize earlier than anterior grafts.

In an animal model, production of serous and purulent effusion material was induced by blocking the Eustachian tube and cleaving the soft palate, respectively. Two and 6 weeks after the different surgical procedures, animals were sacrificed and the membrana Shrapnelli was analysed by light- and electronmicroscopy. The two types of middle ear effusion were associated with various structural changes of the membrana Shrapnelli. In serous otitis media the pars flaccida appeared fibrotic, with large dilated vessels. Sometimes its inner layer, facing the attic space, was contiguous with the investing layer of the ossicles. In purulent otitis media the pars flaccida was thickened and the inner epithelial lining was replaced by a pseudostratified squamous epithelium containing ciliated and secretory cells. Ciliated cells lining the pars flaccida appeared pathognomonic for a longstanding middle ear infection. It is inferred that the structure of membrana Shrapnelli changes under the influence of inflammatory conditions in the middle ear cavity, changes which specifically reflect the different types of otitis media.

Reaction de corps etranger temporaire mais importante. Ne favorise pas la regeneration du tympan. Ces meches ne sont pas satisfaisantes

An ink dot staining method was used to examine epithelial migration in normal ears, in pathologic tympanic membranes, and in external auditory canal cholesteatoma. The direction of the epithelial migration was found to coincide with that of the vessels in normal ears. This suggested that epithelial migration was controlled by the vessels which supply the epidermal layer of the tympanic membrane. In pathologic tympanic membranes and external auditory canal cholesteatomas, epithelial migration was disturbed to various degrees and depended on the local conditions. In these pathologic conditions, the tympanic membrane showed less vascularization. Based on our findings, we believe that a poor blood supply is the major etiologic factor for the epithelial migratory disturbances of the tympanic membrane.

With the rat tympanic membrane used as a model, various topical anesthetics in current clinical use (phenol, Bonain's liquid, and Xylocaine spray) were tested. Structural changes were observed for up to five months from the time of anesthetic application. The most protracted changes affect the lamina propria, which exhibits a pronounced thickening. The extent of the changes, however, differs according to the agent used; for example, phenol applied to discrete areas exhibited the least widespread changes. In the tympanic portion of the lamina propria, the connective tissue was loosely packed with less regularly arranged collagen fibers, while a tightly packed fiber bundle existed on the meatal side. It is inferred that the submucosal connective tissue layer is the portion of the connective tissue layer where the remodeling and reconstruction of the fibrous layer occur.

Topical application of a local anesthetic agent can induce adequate insensibility to pain, and therefore can avoid the use of general anesthesia or invasive infiltration techniques for myringotomy or the insertion of a tympanostomy tube. A comparative study was conducted on a guinea pig animal model to determine the effects of three agents on the structure of the tympanic membrane: 5% tetracaine base dissolved in dimethylsulfoxide (DMSO), pure DMSO, and Bonain's solution. Survival times ranged from 1 day to 3 months. Following removal from the animals, membranes were embedded in Spurr and cut in semithin sections. Signs of mild or severe external otitis were frequent; to avoid non-specific results, infected specimens were not evaluated. Bonain's solution caused loss of the epidermis and mucosal epithelium within 1 day of treatment. The connective tissue layers of the drum were severely hyperplastic after a survival time of 1 month. Tetracaine base in DMSO caused a loss of epithelium and mucosal cells in 3 days. Regeneration started within 7 days and a restitution to integrity was seen after 3 months in drums treated with tetracaine base or DMSO alone.

Recurrent tympanic membrane perforations are usually caused by underlying conditions such as an adhesive process with a poorly aerated middle ear space, a thermal perforation, infection, or technical error at the time of graft placement. Despite surgical treatment these reperforations pose a significant otologic problem that may lead to the development of chronic otitis media and cholesteatoma. The purpose of this study is to detail the use of a new cartilage palisade tympanoplasty technique that has yielded a 100% tympanic membrane closure rate without recurrent perforations in 52 operated ears over a 2-year period. The acoustic properties of the rebuilt tympanic membrane were analyzed for types I, II, and III tympanoplasty and revealed a significant improvement in the postoperative air bone gap.

The inner ear of the leopard frog, Rana pipiens, receives sound via two separate pathways: the tympanic-columellar pathway and an extra-tympanic route. The relative efficiency of the two pathways was investigated. Laser interferometry measurements of tympanic vibration induced by free-field acoustic stimulation reveal a broadly tuned response with maximal vibration at 800 and 1500 Hz. Vibrational amplitude falls off rapidly above and below these frequencies so that above 2 kHz and below 300 Hz tympanic vibration is severely reduced. Electrophysiological measurements of the thresholds of single eighth cranial nerve fibers from both the amphibian and basilar papillae in response to pure tones were made in such a way that the relative efficiency of tympanic and extratympanic transmission could be assessed for each fiber. Thresholds for the two routes are very similar up to 1.0 kHz, above which tympanic transmission eventually becomes more efficient by 15-20 dB. By varying the relative phase of the two modes of stimulation, a reduction of the eighth nerve response can be achieved. When considered together, the measurements of tympanic vibration and the measurements of tympanic and extratympanic transmission thresholds suggest that under normal conditions in this species (1) below 300 Hz extratympanic sound transmission is the main source of inner ear stimulation; (2) for most of the basilar papilla frequency range (i.e., above 1.2 kHz) tympanic transmission is more important; and (3) both routes contribute to the stimulation of amphibian papilla fibers tuned between those points. Thus acoustic excitation of the an uran's inner ear depends on a complex interaction between tympanic and extratympanic sound transmission.

A simple surgical procedure for the repair of cerebrospinal otorrhoea using human fibrin glue has proved safe and successful in two patients with post-surgical fistula. The procedure, which requires only mild sedation, is recommended for open or closed cerebrospinal otorrhoea accompanied by severe neurosensory hearing loss, as long as the fistula has not been caused by chronic inflammatory processes or given rise to intracranial infectious complications.

• The influence of a paper prosthesis on healing in acute traumatic tympanic membrane perforations was studied in 60 patients randomly selected for a treatment group or a control group. The majority (42 [70%]) were seen within two days. All patients were treated with oral antibiotics for ten days. The overall healing rate two months after the trauma was 94% (37 of 39 patients). No significant difference between the study group and the control patients was observed. Intermittent secretion was seen in six patients but did not influence the outcome. The perforations occurred in patients with normally sized mastoid air cell systems as seen on roentgenograms. We conclude that acute traumatic tympanic membrane perforations do not need to be treated routinely with paper patching. ( Arch Otolaryngol Head Neck Surg 1987;113:1285-1287)

Percutaneous healing is plagued by materials compatibility problems, epidermal reactions, and mechanical factors. To our knowledge, no studies have evaluated the effects of one of these factors while controlling the others. The tympanic membrane is an implant site where mechanical factors are minimized. Titanium has been shown to be a very histocompatible material, although no reports of the histology of percutaneous titanium implants exist. This study reports on aspects of the epidermal and connective tissue healing around titanium tympanic membrane implants that were explanted from human subjects. The lack of inflammation and the direct adherence of the tissues substantiate the materials compatibility and the absence of mechanical factors. Tissue healing patterns appear to reach an equilibrium which is suitable for the long-term existence of the percutaneous device. This implant location provides a suitable model for studying the tissue reactions to various percutaneous materials.

Apres un shampooing, 13,5% des oreilles normales presentent de l'eau au niveau du tympan. Apres 4 minutes d'immersion dans l'eau, 52%. Consequences pour les sujets avec perforation tympanique ou tube de ventilation

Otosporin and Gentisone HC ear drops were inserted twice daily for 3 weeks into the external auditory meatuses of guinea pigs. An intraperitoneal injection of vincristine (1 mg/kg.) was given to each animal three hours before it was killed. Temporal bones and attached external auditory meatuses were dissected, tissues were fixed in 10 per cent buffered formalin, decalcified in EDTA, and embedded in JB4 plastic for sectioning at 4 μm. The proliferative activity in the epidermis of the bony meatus and in the lateral surface of the tympanic membrane was obtained by deriving the mitotic indices. After both types of ear drops there was a statistically significant reduction in mitotic indices, the values being about half the control values. The proliferative activity in the tympanic membrane was too low to permit statistical analysis, but no differences were apparent between the groups. The thicknesses of the epidermis and dermis of the bony canal, and of the tympanic membrane, were measured using a Kontron MOP-AM03 analyser. Although the dermis was thinner as a result of the administration of ear drops, both the epidermis of the bony meatus and that of the tympanic membrane were thicker, all these changes being statistically significant.

• It has been believed that in an ear with a perforation, the tympanogram becomes a straight line due to the lack of compliance change in response to the pressure change in the external auditory meatus. Recently, however, we found two types of tympanogram with distinctive characteristics in ears with small perforations. In the first tympanogram type, when the external auditory meatus pressure was changed in the decreasing direction, the compliance peak was formed in the positive-pressure area, whereas it was formed in the negative-pressure area when it was changed in the increasing direction. The difference of the pressure at which compliance peak was obtained was great. The second tympanogram type was unique, with multiple notches similar to those of electronystagmographic recordings of the jerky nystagmus. Knowledge of these tympanograms helps in recognizing small tympanic-membrane perforations. ( Arch Otolaryngol Head Neck Surg 1986;112:642-645)

Otoscopic observation of the tympanic membrane is the most effective noninvasive means of diagnosing and following the course of experimental otitis media in animal models of the disease in both short-term and in longitudinal studies. Because of the difficulty of viewing the entire tympanic membrane of the gerbil model of otitis media without manipulation, we present methods of visualizing and color illustrations of the normal tympanic membrane of the Mongolian gerbil, Meriones unguiculatus. These are compared with illustrations of animals with acute experimental otitis media. An artist's rendition of the entire normal gerbil tympanic membrane is presented. These methods and illustrations will enable investigators to more rapidly and easily adopt the Mongolian gerbil as an animal model for studies of otitis media.

• The long-term results of myringoplasty in children, including closure of perforation and hearing improvement, were reviewed in relation to age, condition of the operated-on ear, and condition of the untreated ear. The overall success rate in 155 operations evaluated one year postoperatively was 79%. Children in the 5- to 8-year-old age group had a success rate comparable to that of older (9- to 12-year-old) children (77.7% vs 80.4%). Where graft failure occurred, it was usually within one year of surgery. The outcome of surgery could not be related to the presence or absence of chronic otitis media in the untreated ear, the status of the operated-on ear (whether dry or discharging), or the performance of adenoidectomy before myringoplasty. Results of postoperative hearing, analyzed by calculating the postoperative air-bone gap and by speech audiometry, were similar in the two age groups. It is concluded that myringoplasty has a good chance of success in children, regardless of age. ( Arch Otolaryngol Head Neck Surg 1987;113:1288-1290)

The present investigation was performed to evaluate the use of laser-Doppler flowmetry as a means for measuring the blood flow of the microcirculation of the human tympanic membrane. The blood cell flux in the microvascular bed of the normal tympanic membrane was measured in healthy subjects. The laser-Doppler output signals continuously recorded showed a steady value ranging from 70 to about 120 V, as well as spontaneous oscillations (or rhythmical active vasomotion). Our findings show that the laser-Doppler instrument tested seems to be useful for evaluating blood flow changes in the microcirculation of the human tympanic membrane.

Otologists have long debated the importance of the mastoid in determining the success or failure of tympanic membrane reconstruction. The pneumatic spaces within the mastoid represent an "air reservoir" which can be drawn upon during periods of eustachian tube dysfunction and buffer the middle ear against the development of detrimental negative pressures. Mastoid inflammatory disease, if untreated, may result in recurrent suppuration and graft failure. Small mastoid volume, aside from its well known association with chronic infectious middle ear disease, has been shown to effect adversely graft survival following myringoplasty. In 48 patients undergoing myringoplasty with simple mastoidectomy, neither small mastoid size nor inflammatory mastoid disease significantly decreased the rate of graft healing. This suggests that simple mastoidectomy is an effective means of repneumatizing the mastoid and eradicating mastoid sources of infection. The successful surgical creation of a pneumatized mastoid cavity in communication with the middle ear was confirmed by postoperative computerized tomographic (CT) scans. In failed cases, CT scanning predictably identified residual mastoid disease. Simple mastoidectomy is considered to be a safe and useful adjunct to myringoplasty in selected cases of chronic otitis media with perforation.

The concentration of hyaluronan (hyaluronic acid; sodium hyaluronate; HA), a major component of connective tissue, was analyzed by a specific radioassay in tissue samples from normal rat middle ears and in tissue and effusions from middle ears affected by experimentally induced otitis media. In normal ears the pars flaccida of the tympanic membrane contained a considerably higher concentration of HA (60 to 200 micrograms/g) than the pars tensa and areas of the medial wall (2 to 7 micrograms/g). In purulent otitis media the pars flaccida contained less HA than in normal ears. The HA concentrations were lower in purulent (3 to 40 micrograms/mL) than in serous (20 to 190 micrograms/mL) effusions. The weight average molecular weight of HA in serous fluid was high (greater than 10(6] and comparable to that in lymph. It is inferred from the study that the subepithelial tissue and its matrix components, eg, HA, must be considered when attempting to understand the function of the middle ear normally and in otitis media.

• Children with secretory otitis who, during the period from 1970 through 1975, had been treated with adenoidectomy and insertion of ventilating tubes were reexamined three to eight years after treatment and, again, ten to 16 years after treatment. The changes of the tympanic membrane were analyzed with regard to the occurrence of attic retractions and changes of the pars tensa of the membranae tympani. At the first follow-up examination, varying degrees of attic retractions were found in 37% of ears and, at the second follow-up examination, in 27% of ears. This general improvement was mainly due to normalization of the slight retractions, whereas the frequency of severe retractions increased. Pathology of the pars tensa of the membranae tympani was found in 57% of ears at the first examination and comprised the following: tympanosclerosis (19%), tympanosclerosis and atrophy (10%), atrophy (22%), atrophy and pexi (3%), and adhesive otitis (3%). At the second follow-up examination, pathology of the pars tensa of the membranae tympani occurred in 58.05% of ears and was distributed as follows: tympanosclerosis (26%), atrophy and tympanosclerosis (11%), atrophy (14%), atrophy and pexi (5%), adhesive otitis (2%), and sinus cholesteatoma (0.5%). ( Arch Otolaryngol Head Neck Surg 1987;113:380-385)

We studied human middle ears from Wittmaack's temporal bone collection in the ENT Department of the University of Hamburg. In the 12-week-old fetus, cells from the embryonic middle ear mesenchyme form a tiny semi-circle around the tympanic part of the developing facial nerve. During the following weeks, the production of fibrillar material increases until the facial nerve is surrounded by a dense fibrous semi-canal. Intramembranous ossification starts from ossification centers in the anlage of the membranous facial canal. Bone appears first in the form of spicules surrounded by osteoblasts. At this time, so-called aplastic areas (aplastische Zonen) can be identified between these spicules. Their importance in the latter occurrence of dehiscenses in the mature facial canal is discussed.

Summary An ink-dot staining technique was used to determine the pattern and rate of epithelial migration in children with normal tympanic membranes. Epithelial migration was observed to occur in a predominantly postero-superior direction. The mean daily rate of migration was 131 μm per day, being at its greatest in the region of the umbo. These findings are compared with those previously recorded in adults.

A eutectic mixture of two anesthetic solutions is that of lidocaine and prilocaine, which is available commercially as Emla (eutectic mixture of local anesthetics). This solution is commonly used in clinics in superficial skin surgery and when inserting intravenous catheters, and we also wanted to determine its surface effects when applied onto the tympanic membranes (TM) of rats and guinea pigs as animal models. The animals were observed by otomicroscopy for 2 weeks up to 5 months after administrations of the anesthetic solution. Tissue specimens were then obtained for light microscopy and fine structural analysis. The application of Emla caused minor structural changes to the rat TM, but hardly any alterations to that of the guinea pig. The changes displayed were an overall increased thickness, with typical submucosal edema but only slight epithelial reaction. In comparison with previous results with lidocaine, phenol and Bonain's solution, Emla seemed to be harmless to the structure of the TM. However, the efficacy of Emla as a topical TM anesthetic remains to be proved in future clinical trials.

A complete otoscopic examination should be performed in all patients seeking treatment of temporomandibular disorders. The presence of a bulge in the external auditory meatus that disappears with mouth opening may suggest the persistence of the foramen of Huschke. The clinicion should rule out the presence or history of infection, trauma, or neoplasm before ascribing the etiology of a defect to a developmental aberration.

The purpose of this study was to determine whether anatomic differences in the tympanic membranes of various species could explain differences in the propensity to form aural cholesteatomas and retraction pockets. Tympanic membranes from humans, dogs, cats, rabbits, guinea pigs, rats, gerbils, and mice were examined histologically. The pars flaccida and pars tensa varied greatly among the species studied. The guinea pig's pars flaccida was very small and had a thin lamina propria. In contrast, the lamina propria of the rabbit and cat pars flaccida were thick. The amount of collagen, elastin, mast cells, and macrophages varied widely. The human and gerbilline tympanic membranes were anatomically dissimilar; for example, the human pars flaccida and pars tensa contained more and denser collagen than did those of the gerbil. The presence of macrophages or mast cells did not correlate with the propensity to develop cholesteatomas. Therefore, anatomic differences among these species do not explain why some develop aural cholesteatomas and others do not.

The atelectatic retraction pocket (ARP) has been implicated in the development of chronic otitis media and cholesteatoma. The ARP's tendency for persistence or recurrence despite treatment is a significant otologic problem. The purpose of this study is to define and discuss this clinical entity and the use of cartilage-perichondrium tympanoplasty as a safe and predictable method of treatment, reducing destructive complications while maintaining ear function. A retrospective analysis of 85 operated ears is presented.

In our previous histological studies of the tympanic membrane, we reported the presence of encapsulated nerve corpuscles that are capable of detecting middle ear pressure. Based on these findings, the relation between sensory receptors in the tympanic membrane and tubal function was examined in a clinical study. Tubal function was tested during Valsalva maneuvers and its active equilibration. Function was recorded as a change of the static compliance of the tympanic membrane on an otoadmittance meter. To paralyze the sensory receptors in the tympanic membrane, iontophoresis was used to induce anesthesia of the drum. Forty ears of 20 subjects were tested. All ears were able to equalize positive middle ear pressure without or with a single swallowing. After anesthesia, 13 ears needed more than two swallows and 4 ears failed to equalize middle ear pressure in spite of repeated swallowings. As eustachian tube function changed following anesthesia of the tympanic membranes, a neural connection between sensory receptors in the tympanic membrane and tubual muscles is suggested.