Histopathologic changes of the tympanic membrane in acute and secretory otitis media

The histopathologic changes observed in 40 normal and inflamed temporal bones of infants and children are reported. The tympanic membranes of patients with acute and secretory otitis media underwent considerable swelling compared to those of normal controls. Tympanic membranes with acute otitis media were thicker than those with secretory otitis media, but the difference was not statistically significant. The epithelial layer showed an increase in the number of cell layers. The lamina propria demonstrated the most significant changes of all layers with a marked swelling due to edema, engorged blood vessels, and inflammatory cell infiltration. Increased numbers of distended capillaries were present, predominantly in the subepithelial connective tissue layer, while infiltration of inflammatory cells was mainly in the submucosal connective tissue layer. By contrast, the involvement of the mucosal layer was modest and was composed of cuboidal cells, except for small islands of metaplastic mucosa with mucus production occasionally encountered in specimens with secretory otitis media.

Afterdrop after hypothermic cardiopulmonary bypass: the value of tympanic membrane temperature monitoring

OBJECTIVES

After weaning from cardiopulmonary bypass (CPB), a decrease in nasopharyngeal temperature (NPT) occurs (afterdrop). The pathophysiology of the afterdrop remains unclear: It might be caused by either inadequate total body rewarming on CPB or to heterogenous distribution of heat during CPB, with subsequent redistribution of heat from the warmer core to the cooler shell tissues. The study objectives were (1) to determine whether post-CPB afterdrop is the result of a negative CPB thermal balance, and (2) to investigate which sites (if any) could best predict the afterdrop.

DESIGN

Prospective evaluation using within-patient comparisons during CPB cooling, CPB rewarming, and 45 minutes post-CPB.

SETTING

Adult patients gave informed consent before a cardiac surgical procedure in a university hospital.

PARTICIPANTS

Eight patients undergoing CABG or valvular replacement with hypothermic CPB (NPT near 29 degrees C) and standardized general anesthesia.

INTERVENTIONS

Each patient was studied with temperature monitors (Mon-a-therm 7000; Mallinckrodt-Medexel, Gemenos, France) attached to disposable thermocouple probes placed as follows: urinary bladder, rectum, deltoid, esophagus, nasopharynx, tympanic membrane, and four skin sites. In addition, the temperatures from the thermistors of the pulmonary artery catheter, and the arterial and venous lines of the CPB circuit were considered. Thirteen sites for monitoring temperature were studied.

MEASUREMENTS AND MAIN RESULTS

Temperatures were recorded every 5 minutes, from the beginning of CPB to the 45th minute after CPB, and thermal exchanges were calculated: change in body heat (QBH), thermal exchanges between the patient and the pump (QCPB), metabolic heat production (Qm) (equal to calculated VO2 at the pump level), and heat loss to the environment (QS) (equal to QBH-QCPB-Qm). Thermal exchanges were obtained in six patients during the plateaus of cooling and rewarming, during the whole CPB phase, and after CPB. It was found that despite a change in QBH during rewarming (1,017 +/- 88 kJ) that was slightly greater than during cooling (-1,008 +/- 104 kJ) (mean +/- SEM), a significant decrease in post-CPB "core" temperature occurred (afterdrop: -1.4 degrees C). Magnitude of the afterdrop was directly related to the magnitude of tympanic membrane cooling and was negatively correlated to the temperature difference between the warmest site (tympanic membrane) and the coolest site (cutaneous thigh temperature) observed at the end of rewarming (r = -0.667; p < 0.05).

CONCLUSIONS

It is suggested that besides post-CPB heat loss, redistribution of heat may be involved in the mechanism of the afterdrop and that measurements of tympanic membrane and cutaneous thigh temperatures are the best monitors of adequacy of rewarming during CPB.

External and middle ear pathology in TGF-alpha-deficient animals

Transforming growth factor-alpha (TGF-alpha) is a growth-regulatory peptide found in a wide range of embryonic and adult tissues. TGF-alpha is produced by keratinocytes and has been reported to be overexpressed in several epidermal diseases, including middle ear cholesteatoma. This report describes ear pathology in the waved-1 mutant mouse, which is severely deficient in TGF-alpha. Morphologic changes of the external and middle ear were studied histologically in waved-1 mutants 2 weeks to 6.5 months of age. Abnormalities found in the mutants included epidermal hyperplasia of the external ear canal (EAC) and tympanic membrane (TM) and enlargement of specialized sebaceous glands adjacent to the cartilaginous EAC. Sebum and desquamated keratin progressively accumulated within the EAC, displacing the TM into the middle ear. These changes appear similar to those occurring in Mongolian gerbils, which are known to develop cholesteatoma. The alterations found in waved-1 mutants are discussed in relation to the possible involvement of TGF-alpha in cholesteatoma pathogenesis.

The pars flaccida middle ear pressure and mastoid pneumatization index

The degree of pars flaccida retraction and the levels of mastoid pneumatization were assessed and correlated in 388 adults with intact pars tensa. Poorly pneumatized mastoids were found to be associated with retraction of pars flaccida; the poorer the pneumatization, the deeper the retraction. Well pneumatized mastoids were usually associated with normal position of the pars flaccida. The pars flaccida was previously also shown to retract in face of ME negative pressure--and its degree can be seen to be an index of ME negative pressure. Thus, the correlation of deeper degrees of pars flaccida retractions with mastoid hypopneumatization (and vice versa) lends strength to the studies which show the mastoid pneumatic system to have a function of a passive ME pressure buffer. This observation lends further evidence as to why ears with poorly pneumatized mastoids are a priori at risk to develop complications such as SOM in adults, tympanic membrane retractions and perforations, incus necrosis or retraction pocket cholesteatoma. Ears with a large pneumatic system are hardly at such risk.

Tubal and tympanic openings of the peritubal cells: implications for cerebrospinal fluid otorhinorrhea

Cerebrospinal fluid otorhinorrhea after surgery for cerebellopontine angle tumors may persist despite obliteration of the mastoid, middle ear, and tympanic orifice of the eustachian tube. In this study, histologic sections of 120 adult temporal bones were examined by light microscopy to determine the incidence of peritubal pneumatization and to demonstrate the frequency of tubal and tympanic openings of the peritubal cells. The results of this study suggest that the pathway for these persistent cerebrospinal fluid leaks may be via the peritubal cells that open directly into the eustachian tube anterior to its tympanic orifice. Peritubal pneumatization was present in 78 (65%) of the temporal bones. Of the 57 specimens in which the openings of the peritubal cells could be identified, in 52 (91%), the cells opened into the eustachian tube anterior to its tympanic orifice, and in only five (9%), they opened into the middle ear. The overall incidence of tubal openings in this study was 59%. In 13 temporal bones (21%), the tubal opening were at a distance of > 5 mm anterior to the tympanic orifice of the eustachian tube. Therefore, cerebrospinal leak may persist through these tubal openings despite obliteration of the mastoid, middle ear, and tympanic orifice of the eustachian tube. A case of persistent cerebrospinal fluid leak in which extensive peritubal pneumatization was demonstrated by computed tomography scan is presented. Successful control of the leak was obtained only after the tubal openings of these cells several millimeters anterior to the tympanic orifice were obliterated.

Vein graft in stapes surgery

Sealing the opening of the oval window during stapes surgery is essential; it prevents postoperative complications, such as perilymph fistula and sensorineural hearing loss. In this small series of 269 cases with otosclerosis, tympanosclerosis, and congenital ossicular abnormality, vein grafting was used to seal the opening of the footplate. Hearing improvement after surgery was acceptable, and none had total hearing loss or perilymphatic fistula. World literature from the last half of this century on grafting the oval window is reviewed. Absorbable gelatin sponge (Gelfoam) seems to be causing more complications, so its use is highly discouraged. Temporalis fascia, fat, and perivenous loose areolar tissue have been used by different authors at different times in footplate surgery. The opening created in the oval window during stapes surgery must not be left uncovered.

The contralateral ear in patients with chronic otitis media

The status and hearing function of the contralateral ears in 493 patients undergoing surgery for chronic otitis media were studied at the final follow-up examination of the patients (on average, 6.5 years after the surgical treatment). In only 37% of the patients was the contralateral ear found to be normal, with atrophy of the pars tensa and tympanosclerosis being the most common abnormal findings, followed by pars tensa and attic retractions. In 18% of the patients, the contralateral ear had also undergone surgery. In only 64% of the patients, the contralateral ears had normal (< or = 20 dB) hearing levels, and in 21%, the hearing levels were > 30 dB, the hearing function of patients with cholesteatoma being worse than that of other patients with chronic otitis media. In 14 (3%) of the patients, even the better hearing ear had a hearing level of > 60 dB, including one patient with both ears totally deaf. To improve the functional outcome of patients with chronic otitis media, earlier and more effective treatment of middle ear infections is needed.

Is perilymphatic pressure altered in tinnitus?

Tinnitus is characterized by the continuous or intermittent auditory perception of various sounds (buzzing, whistling, etc.) in the absence of any external stimulus. Perilymphatic hyperpressure is one of the numerous mechanisms which could hypothetically be involved in tinnitus generation. In the present experiment, perilymphatic pressure was measured indirectly using the tympanic membrane displacement technique. Twenty-five tinnitus patients were investigated at 10, 15 and 20 dB above the acoustic reflex threshold with ipsilateral stimulation. The variables Vi (inward tympanic displacement), Vm (mean tympanic displacement) and their variations according to stimulus level were compared between tinnitus sufferers and age-matched or hearing-matched controls. Tympanic displacement was measured in sitting and supine positions so as to evaluate cochlear aqueduct patency. No systemic changes in response occurred in tinnitus patients, except at a high stimulation level, perhaps due to hearing impairment.

Aging effects in multifrequency tympanometry

OBJECTIVE

The objective of this investigation was to determine the effect of the aging process on various measures derived from multifrequency tympanograms.

DESIGN

Tympanograms were recorded at 226 Hz and at one-sixth octave intervals from 250 through 2000 Hz from 136 adult male subjects; 20 in each decade of life from age 20 through age 79 and 16 older than 79 yr of age. Analyses were performed on two measures of resonant frequency of the middle ear, two measures of static admittance at 226 Hz, and tympanometric width at 226 Hz.

RESULTS

No systematic effect of age on any of these measures was evident in this population except for a small, but significant, correlation between tympanometric width and age. Analyses of variance indicated no significant difference among mean values on any measure when subjects were grouped by decade of life. Values of these tympanometric variables are reported to add to the growing base of data from normal low-frequency and multifrequency tympanograms.

CONCLUSIONS

The main finding of this investigation indicates that normative values of middle ear resonance, admittance, and tympanometric width obtained from groups of adults of various ages can be applied to elderly men.

[Multifrequency tympanometry in Meniere's disease: preliminary results]

Tympanometry with 220 Hz probe tone mainly measures compliance related components of the middle ear. Only higher frequency probe tones provide information on mass related components. In order to study the behavior of the mass related components in endolymphatic hydrops, the Authors tested 15 Ménière's disease patients and 10 healthy subjects using multifrequency tympanometry. In both groups tympanometry with 220 and 678 Hz probe tone was employed to evaluate resonance frequency. The presence of a "camel hump" ([symbol: see text]) pattern obtained with the 678 Hz probe tone test indicated an elastic tympano-ossicular system (low point of middle ear resonance); the presence of an inverted "V" ([symbol: see text]) pattern showed a more rigid system (high point of middle ear resonance). In Ménière's disease carriers multifrequency tympanometry revealed 21 ears (70%) with a resonance frequency higher and 6 (20%) lower than 678 Hz. Three patterns (10%) were not classifiable. In the healthy group resonance frequency resulted lower than 678 Hz in 23 ears (57.5%); in 13 ears higher (32.5%). Four patterns (10%) were not classifiable. In Ménière's disease carriers the tympanometric patterns found with 678 Hz probe tone indicated the presence of a more rigid tympano-ossicular system.

Sinus tympani: retrofacial approach for the removal of cholesteatomas

The epithelium basement membrane of cholesteatomas in cases of chronic otitis media often extends into the sinus tympani. In the majority of cases it can be safely and completely removed by dissection through the ear canal and tympanum. In 2% of cases, not all squamous epithelium basement membrane can be removed because the sinus tympani extends more than 3 or 4 mm posterior to the anterior edge of the facial nerve and because the membrane is adherent to the irregular bony surface. Surgical exposure of the sinus tympani through the mastoid posterior and medial to the facial nerve allows complete removal of all basement membrane with a direct view. The technique using a retrofacial approach to expose this obscure sinus is described and a series of 48 cases treated successfully by this method are reported.

Preservation of cochlear function after extensive labyrinthine destruction

We report a case of hearing preservation after removal of the semicircular canals and discuss the possible explanations for the mechanisms of preservation of hearing after removal of the labyrinth. We hope to promote the perspectives and possibilities of functional surgery of the inner ear and for tumors of the cerebellopontine angle.

The effect of tympanic membrane perforation size on umbo velocity in the rat

The tympanic membrane (TM) in adult rats was surgically exposed and laser interferometry was used to measure TM velocity at the umbo for frequencies between 1.0 and 40.0 kHz. Velocity measures were obtained for five conditions: TM intact, and four progressively larger holes cut into the posterior region of the membrane. Photomicrographs of each condition were used to calculate the percentage of pars tensa lost to the perforation. The relation between TM velocity and stimulus sound pressure level (SPL) was also examined for each of the conditions. The results revealed a systematic loss in low-frequency velocity as perforation size increased. These observations were consistent with clinical reports of low-frequency hearing loss in the perforated human TM. The rat appears to be a successful model for studying this form of conductive pathology.

Changes in middle ear pressure in daily life

The present study was performed to estimate changes of middle ear pressure (ME-P) during actions of daily life such as nose blowing and sniffing. ME-P was measured in 18 patients with perforation of the eardrum. They were asked to perform actions which included nose blowing and sniffing. Eustachian catheterization and politzerization were also applied. Change of ME-P before and after these actions was recorded using a pressure monitor. Results showed that changes of ME-P after nose blowing with both nostrils closed were large and rapid. The mean value of ME-P after nose blowing was 252 mmH2O. In our previous study, the mean value of cerebrospinal fluid pressure (CSF-P) after nose blowing was 388 mmH2O. Therefore, the pressure gradient across the cochlear windows is about 130 mmH2O during nose blowing. The cochlear windows may have been pressed toward the middle ear side. After sniffing, ME-P was unchanged. These results suggest that nose blowing may be an important cause of perilymphatic fistula (PLF) via the "explosive route", while sniffing is not likely to cause PLF.

Cytokeratin expression patterns by one- and two-dimensional electrophoresis in pars flaccida cholesteatoma and pars tensa cholesteatoma

Expression patterns of cytokeratins (CKs) in normal skin, in pars flaccida type cholesteatoma (PFTC), and in pars tensa type cholesteatoma (PTTC) were examined by means of one- and two-dimensional electrophoretic techniques. Both CKs 14 and 5 pair (CKs 14/5) and CKs 10/1 were found in all materials. Neither CKs 16/6 nor 19 was found in the skin. CKs 16/6 and 19 were both found in 3 out of 5 PFTCs, only CKs 16/6 in 1 out of 5 and neither CKs 16/6 nor 19 in 1 out of 5. CKs 16/6 and 19 were both found in 1 out of 3 PTTCs, only CKs 16/6 in 1 out of 3 and neither CKs 16/6 nor 19 in 1 out of 3. There was no significant difference in the CKs expression patterns between PFTC and PTTC. The expression of CKs 16/6 and 19 suggested that their matrix epithelia were hyperproliferative. However, not all of the cholesteatomas were always hyperproliferative. Patterns of the terminal differentiation of CKs 1, 5, 10 and 14 in the PFTC or the PTTC were basically the same as those in the skin. In the cholesteatoma, eack CK gradually diminished in molecular weight in the cornified layer and debris. Desmosomal proteins were abundant in skin but not in cholesteatomas.

Growth factors in wound healing

Growth factors are signal proteins that regulate the cellular processes in wound healing. By manipulating the actions of growth factors, it may be possible to accelerate or modify wound healing. Currently, intense research is being conducted throughout the world to investigate this possibility. In otolaryngology, the impact of improved wound healing could be tremendous. This article discusses the involvement of growth factors in soft-tissue healing that is relevant to otolaryngology.

Tympanic membrane wound healing. An overview

This article is a comprehensive overview of tympanic membrane injury and its healing. Its wound healing process is unique from soft tissue because epithelialization occurs before fibrous tissue advancement. Contemporary and future modalities to improve tympanic membrane repair are also discussed in this article.

Intracranial pressure at high altitude and acute mountain sickness

1. Raised intracranial pressure has been noted in severe forms of acute mountain sickness and high-altitude cerebral oedema, but the role of intracranial pressure in the pathogenesis of mild to moderate acute mountain sickness is unknown. 2. Serial measurements of intracranial pressure were made indirectly by assessing changes in tympanic membrane displacement in 24 healthy subjects on rapid ascent to 5200 m. 3. Acute hypoxia at 3440 m was associated with a rise in intracranial pressure, but no difference was found in pressure changes at 4120 or 5200 m in subjects with or without symptoms of acute mountain sickness. 4. Raised intracranial pressure, though temporarily associated with acute hypoxia, is not a feature of acute mountain sickness with mild or moderate symptoms.

Reliability and validity of tympanic temperature measurement in persons with high spinal cord injuries

Tympanic temperature measurements in the able bodied have been well studied and validated in previous investigations. This validation has not been studied in individuals with high spinal cord injuries where autonomic control is different above and below the level of the lesion, which makes the accuracy of this measurement for core body temperature questionable. In this correlational study we look at the reliability and validity of tympanic temperature measurement in individuals with high spinal cord injuries in comparison to oral and rectal temperature measures. The rectal measurement proved to be the most reliable with an r value of 0.975 overall. The oral was minimally better than the tympanic with r values of 0.88 and 0.86, respectively. The validity of the oral measure in predicting changes in the rectal temperature (gold standard) was slightly better than the tympanic with r values of 0.88 and 0.77, respectively. Both the oral and tympanic measures accurately reflected changes in the rectal (core) temperature.

[Lightening strike injuries of the ear]

Although lightning injuries are quite common, lightning-induced damage to the middle or inner ear and to the vestibular nerve has been reported in only a very few cases. Two case reports are presented: a 22-year-old woman and a 26-year-old man who experienced lightning injuries to several body parts including the ear. Pathophysiology, diagnostic criteria and treatment are discussed.