Prevention of sinus tympani retraction following tympanoplasty. How I do it

Tympanoplasty for sinus tympani retraction may result in delayed recurrence of the original problem. This is especially true in children with marginal eustachian tube function. Autogenous tragal cartilage, scored on one surface with perichondrium attached on the other, produces a "natural bend" in the cartilage. When placed in the middle ear, with the scored convex surface facing the promontory, retraction into the sinus tympani can be prevented. This simple, yet effective, surgical technique is outlined.     

Surgery for acquired cholesteatoma in children: long-term results and recurrence of cholesteatoma

The aim of the study was to evaluate the long-term results after surgery for acquired cholesteatoma in children and to contribute to the search for predictors of recurrence. During a 15-year period, 114 children underwent surgery. The patients were re-evaluated with a median observation time of 5.8 years. At the last re-evaluation 85 per cent of the ears were dry with an intact drum. Recurrence of cholesteatoma developed in 27 ears. The cumulated total recurrence rate was 24 per cent using the incidence rate calculation, applying Kaplan-Meier survival analysis the corresponding recurrence was 33 per cent. Recurrent disease occurred significantly more frequently in children younger than eight years, with a negative pre-operative Valsalva, with ossicular resorption and with large cholesteatomas. In conclusion, young children with poor Eustachian tube function and a large cholesteatoma with erosion of the ossicular chain, are at special risk of recurrence and should be observed for several years after surgery.     

Congenital cholesteatoma of temporal bone

Cytomegalovirus infection causing symptomatic enteritis is most usually associated with immunosuppressed transplant patients or patients positive for human immunodeficiency virus. Most reports studying this illness are small and do not clearly define the risk factors or mortality rates. METHODS: The present study retrospectively reviewed the charts of 67 patients with biopsy-proven cytomegalovirus enteritis (esophageal, gastric, small bowel, and colonic) to define and to investigate factors that influence survival. Patients were classified into four groups based on underlying medical condition: 1) patients positive for human immunodeficiency virus; 2) transplant patients receiving immunosuppressive medications; 3) immunosuppressed nontransplant patients; and 4) otherwise healthy individuals. Mortality rates based on underlying medical condition, location of intestinal cytomegalovirus infection, cytomegalovirus therapy, age, and average days to institution of treatment were defined and statistically assessed. RESULTS: Mortality was significantly greater in the normal patient group (80 percent) than in the transplant (21 percent), other immunosuppressed (44 percent), or human immunodeficiency virus-positive (75 percent) groups (P = 0.0006, Cochran-Mantel-Haenszel statistics). There was no difference in mortality based on intestinal location of disease or treatment modality (surgery, medical therapy, or both). Cohorts of patients older than 65 years had a statistically higher mortality rate vs. those younger than 65 years old (68 vs. 38 percent; P = 0.05, Cochran-Mantel-Haenszel statistics). Statistically increased mortality was also associated with increased time from hospital admission to institution of cytomegalovirus treatment, whether therapy was medication alone or medication and surgery (P < 0.05, exact Wilcoxon's test). CONCLUSIONS: 1) Lethal cytomegalovirus enteritis can arise in patient populations not typically identified as being at risk for this disorder, including normal individuals. 2) Mortality in cytomegalovirus enteritis is adversely associated with age older than 65 years and increased time to institution of therapy but is not affected by anatomic site of infection or particular form of treatment. Paradoxically, in this study, normal patients had the highest mortality, which we attribute to a low index of suspicion and relatively late institution of therapy.     

Mastoid pneumatization in children with congenital cholesteatoma: an aspect of the formation of open-type and closed-type cholesteatoma

We investigated the effect of spirulina on mast cell-mediated immediate-type allergic reactions. Spirulina dose-dependently inhibited the systemic allergic reaction induced by compound 48/80 in rats. Spirulina inhibited compound 48/80-induced allergic reaction 100% with doses of 100-1000 microg/g body weight, i.p. Spirulina (10-1000 microg/g body weight, i.p.) also significantly inhibited local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. When rats were pretreated with spirulina at a concentration ranging from 0.01 to 1000 microg/g body weight, i.p., the serum histamine levels were reduced in a dose-dependent manner. Spirulina (0.001 to 10 microg/mL) dose-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP in RPMC, when spirulina (10 microg/mL) was added, transiently and significantly increased about 70-fold at 10 sec compared with that of control cells. Moreover, spirulina (10 microg/mL) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha production. These results indicate that spirulina inhibits mast cell-mediated immediate-type allergic reactions in vivo and in vitro.     

The origin of congenital cholesteatoma

Transgenic potatoes were engineered to synthesize a cholera toxin B subunit (CTB) pentamer with affinity for GMI-ganglioside. Both serum and intestinal CTB-specific antibodies were induced in orally immunized mice. Mucosal antibody titers declined gradually after the last immunization but were restored following an oral booster of transgenic potato. The cytopathic effect of cholera holotoxin (CT) on Vero cells was neutralized by serum from mice immunized with transgenic potato tissues. Following intraileal injection with CT, the plant-immunized mice showed up to a 60% reduction in diarrheal fluid accumulation in the small intestine. Protection against CT was based on inhibition of enterotoxin binding to the cell-surface receptor GMI-ganglioside. These results demonstrate the ability of transgenic food plants to generate protective immunity in mice against a bacterial enterotoxin.     

Serotoninergic innervation of stapedial and tensor tympani motoneurons

cGMP-immunostaining in the islands of Calleja (ICj) in slices incubated in vitro partially co-localized with nitric oxide synthase (NOS) inside the ICj. No cGMP-immunostaining was found outside the ICj in unstimulated slices, whereas the NO-donor sodium nitroprusside (SNP) stimulated cGMP in cells and fibers bordering on the ICj. These findings show an ongoing NO synthesis in in vitro slices and suggest a relatively restricted diffusion range for endogenously synthesized NO.     

Effects of chorda tympani nerve anesthesia on taste responses in the NST

Human clinical and psychophysical observations suggest that the taste system is able to compensate for losses in peripheral nerve input, since patients do not commonly report decrements in whole mouth taste following chorda tympani nerve damage or anesthesia. Indeed, neurophysiological data from the rat nucleus of the solitary tract (NST) suggests that a release of inhibition (disinhibition) may occur centrally following chorda tympani nerve anesthesia. Our purpose was to study this possibility further. We recorded from 59 multi- and single-unit taste-responsive sites in the rat NST before, during and after recovery from chorda tympani nerve anesthesia. During anesthesia, average anterior tongue responses were eliminated but no compensatory increases in palatal or posterior tongue responses were observed. However, six individual sites displayed increased taste responsiveness during anesthesia. The average increase was 32.9%. Therefore, disinhibition of taste responses was observed, but infrequently and to a small degree in the NST At a subset of sites, chorda tympani-mediated responses decreased while greater superficial petrosal-mediated responses remained the same during anesthesia. Since this effect was accompanied by a decrease in spontaneous activity, we propose that taste compensation may result in part by a change in signal-to-noise ratio at a subset of sites.     

Intact canal wall tympanoplasty in the management of cholesteatoma

There are presently two schools of thought on the proper surgical management of cholesteatoma associated with chronic ear disease: one feels that the ear should be exteriorized and left "open"; the other takes the position that the disease can be removed, and the ear left in its normal anatomical and functional state. The latter group are known to favor a "closed" or more conservative procedure. The purpose of this paper is to review a series of patients who have had cholesteatoma managed by an intact canal wall procedure that prevents a postoperative cavity. Out of a series of 590 chronic ear surgeries performed between January 1, 1970, and December 31, 1974, there were 179 done for cholesteatoma (30 percent). There were 153 patients, 26 of whom had bilateral disease. Twenty-three patients were lost to follow-up, giving an overall total of 154 surgeries with from one to five-year information. The overall follow-up rate was 85 percent. Recurrent cholesteatoma was the most bothersome complication and occurred in 14 percent of the series. Residual cholesteatoma was managed by doing all procedures in two stages. The authors feel that the intact canal wall tympanoplasty is a procedure that will gain acceptance and will be more widely used in the future.     

Intensity coding in the transient portion of the rat chorda tympani response.

For assessment of the relative importance of the transient and steady state components of the chorda tympani response to intensity coding of gustatory stimuli, the rat's ability to discriminate aversive solutions following adaptation was compared with changes in the neural response also resulting from adaptation. Two experiments were conducted with a total of 12 male hooded Long-Evans rats. A taste aversion was conditioned to .9% NaCl, and subsequent acceptance of several NaCl concentrations (range: .1%–2.5%) was tested following infusion of 1 ml of adapting solution (H?O of .1%, .9%, or 1.5% NaCl) through an intra-oral cannula. Adaptation significantly decreased gustatory intensity discrimination and decreased the magnitude of the transient portion of the chorda tympani response. The degree of reduction in transient magnitude correlated significantly with the reduced discrimination in all adapting conditions; magnitude of the steady state response, however, negatively correlated with discrimination. These data suggest that gustatory intensity discrimination depends on information contained in the transient portion of the neural response and that the transient is necessary suffient for taste intensity discrimination. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tensor tympani, a 'tuner' of tensor palati muscle

The author has proved experimentally (in two dogs) that there is reflex hypertonia of the tensor palati muscle, synchronous with the 'shortening' reaction of the tensor tympani muscle in response to its "static" relaxation during the gradual passive inward displacement of the drum resulting from the negative intratympanic 'dip' due to absorption of air imprisoned within the middle ear. The author coined the term 'tuning' for the reflex hypertonia of tensor palati which is directly proportional to the degree of the slackness of its 'tuner', the muscle-tensor tympani. The degree of opening of the eustachian tube on swallowing depends upon the degree of 'tuning' of the tensor palati. The 'untuned' tensor palati fails to open the eustachian tube during swallowing. Presumably the excitation of tympanic chemoreceptors (glomus body) by the excess of CO2 during hypoxia of the tympanic cleft strengthens the 'shortening' reaction as well as the excitability of the tensor tympani muscle.     

Cross-sectional area of scala tympani in human and cat

The cross-sectional area of scala tympani is measured in midmodiolar sections of both human and cat temporal bones (20 pairs each). The areal sizes of scala tympani in different turns of human cochlea are more than twice those in the cat. A noticeable area reduction between the lower basal turn and the upper basal turn is found in the cat. The cross-sectional view of scala tympani is ovoid to round and flat on top in the basal turns, but it is more like a flat triangle in the lower middle turn and above. The area measurement of the scala tympani assists the development of the implantable electrode. The information also contributes to the construction of models for physiological experiments.     

Anatomo-topographical bases of post-tympanoplasty recurrence of cholesteatoma

25 specimens of the temporal bone were studied to ascertain specific anatomical features of the pockets and sinuses of the tympanic cavity provoking cholesteatoma recurrence after tympanoplasty. An original method is provided of systemic revision of the tympanic cavity along the perimeter to detect and remove cholesteatoma parts hidden in the tympanic cavity pockets and sinuses. After application of the above method the occurrence of the recurrences went down to 9.7%. Intraoperative findings show that cholesteatoma may invade each pocket and sinus of the tympanic cavity both in primary epi-, epimesotympanitis and in cholesteatoma recurrence following open and closed tympanoplasty. In both groups sinus of the facial nerve, posterior tympanic sinus and tympanic cavity suffer most frequently.     

Improvement of the surgical technique of anterior tympanoplasty in cholesteatoma

Technical improvements in anterior tympanotomy with a transmastoid approach in cholesteatoma surgery are reported. Mastoidectomy must be extended to the root of the zygoma and the space anterior to the malleus head must be opened. For this purpose, the visual axis must coincide with the external meatal axis. In this head position, complete removal of the anterior attic bony plate becomes possible only through the transmastoid approach, without touching the ossicular chain. In the case of the pyramidal type bony plate with a normal ossicular chain, the incudo-malleal joint is temporary subluxated, as this is more convenient for access and removal of pathology than incudostapedial joint subluxation. Our clinical results on postoperative hearing showed no damage to the inner ear by the improved technique.     

Predictive factors of residual cholesteatoma in children

The decision on the appropriate surgical technique for treating cholesteatoma in children raises a number of controversial questions, most because of personal convictions rather than because of established data. We attempted to determine which patients are at risk of residual cholesteatoma in order to propose the most rational therapeutic strategy. A retrospective study of 250 children with cholesteatoma or severe retraction underwent surgery between 1986 and 1992. During this period 69 cases of residual cholesteatoma were recorded during a second intervention. After a mean follow-up of 33 months after the final operation, the Kaplan-Meier plot shows a rate of 31% and 34% at 3 and 5 years respectively. The univariate and multivariate (Cox regression) analysis was performed to search for a correlation between residual cholesteatoma development and past history including type of process involved, peroperative findings and surgical technique. Three factors were closely and independently related (p < 0.003) to residual cholesteatoma: invasion of the posterior middle ear, presence of ossicular erosion after excision and presumption of incomplete ablation. Inversely, age, surgical history, extension and nature of the process involved as well as surgical technique had no effect on development of residual cholesteatoma. Only one comparable study has been published where only ossicular erosion was found to be significant on multivariate analysis. The presence of one or more of the three of the factors mentioned above should lead to a second intervention, perhaps after a short delay, whatever the initial technique (open or closed).     

Anion modulation of taste responses in sodium-sensitive neurons of the hamster chorda tympani nerve

Beidler's work in the 1950s showed that anions can strongly influence gustatory responses to sodium salts. We have demonstrated "anion inhibition" in the hamster by showing that the chorda tympani nerve responds more strongly to NaCl than to Na acetate over a wide range of concentrations. Iontophoretic presentation of Cl- and acetate to the anterior tongue elicited no response in the chorda tympani, suggesting that these anions are not directly stimulatory. Drugs (0.01, 1.0, and 100 microM anthracene-9-carboxylate, diphenylamine-2-carboxylate, 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonate, and furosemide) that interfere with movements of Cl- across epithelial cells were ineffective in altering chorda tympani responses to 0.03 M of either NaCl or Na acetate. Anion inhibition related to movements of anions across epithelial membranes therefore seems unlikely. The chorda tympani contains a population of nerve fibers highly selective for Na+ (N fibers) and another population sensitive to Na+ as well as other salts and acids (H fibers). We found that N fibers respond similarly to NaCl and Na acetate, with spiking activity increasing with increasing stimulus concentration (0.01-1.0 M). H fibers, however, respond more strongly to NaCl than to Na acetate. Furthermore, H fibers increase spiking with increases in NaCl concentration, but generally decrease their responses to increasing concentrations of Na acetate. It appears that anion inhibition applies to taste cells innervated by H fibers but not by N fibers. Taste cells innervated by N fibers use an apical Na+ channel, whereas those innervated by H fibers may use a paracellularly mediated, basolateral site of excitation.     

Taste in chimpanzees II: single chorda tympani fibers

Data are presented from 48 taste fibers in chorda tympani nerves of 10 chimpanzees during taste stimulation with 29 stimuli. The results demonstrated a higher taste fiber specificity than in any other mammalian species reported; breadth of tuning equals 0.3. Hierarchical cluster analysis separated an S-cluster (50% of all fibers), an N-cluster (31%), and a Q-cluster (19%). The S-cluster showed the highest specificity. Its fibers responded, with few exceptions, to every sweetener tested, including the sweet proteins brazzein and monellin. The response grew with increasing sweetener concentration. A large response to one sweetener was generally accompanied by a large response to all other sweeteners, and vice versa. Except for one broadly tuned fiber, the fibers of the S-cluster never responded to the bitter compounds. The fibers of the Q-cluster were more broadly tuned than any other fibers. Quinine hydrochloride was their best stimulus, but most fibers were also stimulated by KCl and NaCl with amiloride. Acids stimulated some of these fibers. The N-cluster could be divided into 3 subclusters: an Na-subcluster (3 fibers), Na-K subcluster (10 fibers), and M-subcluster (3 fibers). The Na-fibers responded strongly to, and were quite specific to, NaCl and LiCl stimulation but not to KCl, and fibers of the Na-K subcluster responded equally well to NaCl and KCl. The response to NaCl was suppressed by amiloride in the fibers of the Na-subcluster, but not in the fibers of the Na-K subcluster. Umami compounds elicited the strongest responses in the M-subcluster.     

Advances in the study of the etiology and pathogenesis of middle ear cholesteatoma

Ninety-three consecutive treadmill exercise stress test were performed for the assessment of peripheral vascular function. Thirty-one were for atypical claudication-like symptoms including pain on standing, relief on sitting and back pain. Pedal pulses were palpable in 24 patients. Twenty-five patients (81%) had a negative stress test, suggesting a non-vascular aetiology and this finding was subsequently confirmed in 24 of the 25. The final diagnoses were spinal stenosis 13, [CT = 3, myelogram = 5, neurosurgeon opinion = 4, MRI = 1], myositis 2, restless leg syndrome 2 and osteoarthritis 7. Four patients had symptoms due to a combination of peripheral occlusive arterial disease and spinal stenosis; the latter was considered the predominant disorder in all four. Of the original 31 patients with atypical symptoms, spinal stenosis was present in 13 (42%). Atypia- in the common syndrome of intermittent claudication should alert the surgeon to the possibility of spinal canal disorders. Further investigation may identify significant pathology spinal stenosis in particular.