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Small cavity mastoidectomy--5 year review.

It has been recognized that the traditional method of open mastoid surgery often produces a larger mastoid cavity than necessary. Small cavity mastoidectomy is advocated to reduce the size of the mastoid cavity by exteriorizing the cholesteatoma from the epitympanum backwards. When this operation is performed in a sclerotic mastoid bone, the resulting cavity is very small. The 5 year review of 39 ears with small cavity mastoidectomy is presented. Not only were the mastoid cavities small, they remained stable and trouble-free. It also enabled the patients to enjoy swimming and minimizing wax accumulation within the cavities. The hearing results after 5 years were comparable to that of the closed technique. Formation of cholesterol granuloma behind the concho-meatal flap was an uncommon complication.

Cholesteatoma↗

Reconstruction of the posterior canal wall with Proplast.

Many ears with prior radical or modified radical mastoidectomy operations can be rehabilitated by reconstruction of the posterior canal wall with the porous biocompatible implant material Proplast. Many techniques have been advanced for reconstruction of the posterior canal wall and/or obliteration of the mastoid bowl. We prefer reconstruction of the posterior canal wall to obliteration of the mastoid bowl on the theoretical grounds that with obliteration you lose the pneumatic buffer of the mastoid air cell system and you might be burying infection and/or cholesteatoma in the depths of the mastoid. In this article we shall present our results with elimination of the open mastoid bowl by reconstruction of the posterior canal wall with Proplast. A retrospective study of 83 consecutive patients who underwent reconstruction of the posterior canal wall with Proplast during the 5-year period 1974 to 1978 was undertaken. The surgical technique consisted of rebuilding the tympanic membrane, when necessary, repairing the ossicular chain, when necessary, and reconstructing the posterior canal wall. The overall success rate for the posterior canal wall reconstructions was 46% (38 of 83). However, after modifications were made in the technique, especially in the use of thicker fascia and/or perichondria and periosteum over the Proplast, the success rate increased dramatically to 68% (19 of 28).

Ear Canal↗

Computed tomography evaluation of air cells in the petrous bone--relationship with postoperative cerebrospinal fluid rhinorrhea.

The anatomy of air cells in the petrous bone was investigated using thin-slice bone-window computed tomography (CT) of 168 petrous bones in 84 patients. Air cells in the petrous bone were classified into mastoid and petrous cells. Petrous cells were subdivided into perilabyrinthine and apical cells. Perilabyrinthine cells comprised supralabyrinthine and infralabyrinthine cells. Supralabyrinthine cells were subdivided into posterosuperior, posteromedial, and subarcuate cells. The mastoid was classified as eburnated (11%) or pneumatized (89%) by the extent of the mastoid cells. The mastoid cells were classified into presinusoidal (14%), sinusoidal (44%), and postsinusoidal (42%) according to the relationship with the sigmoid sulcus. The extent of the mastoid cells was significantly correlated with the pneumatization of the petrous apex, i.e. the apical cells (p < 0.01). CT precisely depicted the complex anatomy of the air cells in the petrous bone. Cerebrospinal fluid (CSF) rhinorrhea is the most common complication after skull base surgery for cerebellopontine angle tumors. Air cells in the petrous bone provide the route for CSF rhinorrhea. Therefore, CT assessment of the air cells is useful for preventing this complication.

Adult↗

Reconstruction of the posterior auditory canal with hydroxyapatite-coated titanium.

There are a variety of techniques for treating chronically discharging radical mastoid cavities. The purpose of this article is to report the preliminary results of an original technique for reconstruction of the posterior auditory canal using a titanium net combined with porous hydroxyapatite coating. Titanium is fixed with two screws to the mastoid tip and zygomatic root to prevent the risk of implant dislocation. Eight patients with chronically discharging radical mastoid cavities that failed medical management underwent reconstruction of the mastoid cavity using this technique. After surgery, all cases had rapid healing and good aeration of the middle ear and mastoid. One tympanic membrane reperforated, and no extrusion of the prostheses were detected clinically or on computed tomography scanning. The minimum postoperative follow-up period has been 12 months (range 12-48 months). To date, there has been no evidence of cholesteatoma recurrence. The preliminary results remain encouraging. Larger series and longer follow-up, however, are advisable to prove real validity.

Adult↗

[A case of Bezold's abscess associated with cholesteatoma].

Since the advent of antibiotics, otogenic complications have decreased considerably. However, incomplete antibiotic therapy has altered the clinical course of middle ear disease so as to be more insidious. This paper reports a case of Bezold's abscess associated with cholesteatoma. A 48-year-old man visited our hospital presenting with a 4-day history of right otorrhea and a tender swelling in the right neck. Physical examination showed a febrile patient (38.8 degrees C) with right facial paresis and trismus. A hyperemic, hard and tender swelling was observed in his right neck from the lateral cervical to the mental region. The tympanic membrane was invisible because of granulation and swelling of the posterior wall of the external auditory canal. Intravenous clindamycin and ceftazidime therapy was started immediately. A CT-scan revealed a diffuse shadow with bony destruction in the right mastoid cortex. Extensive abscess formation was also found in the right sternocleidomastoid muscle, in the anterior neck and in the posterior neck. He was diagnosed as having Bezold's abscess associated with cholesteatoma. Radical mastoidectomy and drainage of the neck abscess was performed on the third day under general anesthesia. The mastoid cavity was found to be filled with pus and cholesteatoma debris. A small area of defective bone was found at the mastoid tip, through which there were communications between the mastoid cavity and the abscesses in the neck. Bony destruction was also found in the horizontal and vertical portion of the facial canal. Bacteroides and three kinds of gram-negative rods were cultured from the mastoid cavity.(ABSTRACT TRUNCATED AT 250 WORDS)

Abscess↗

Sinusitis: hidden source of sepsis in postoperative pediatric intensive care patients.

Paranasal sinusitis is reported as a complication of prolonged nasal intubation and the source of sepsis in adult intensive care patients. In surgical neonates with congenital malformations, prolonged intubation with a nasotracheal (NT) or NG tube is often necessary, but sinusitis with complicating sepsis is seldom reported. Sinus x-rays may confirm the diagnosis; in infancy, prolonged nasal intubation delays the pneumatization of the sinuses and the mastoids, resulting in additional diagnostic problems. In a 1-yr period, we saw three patients with multiple septic episodes in which the source of sepsis was undetectable. Despite the absence of clinical symptoms and radiologic evidence of sinusitis or mastoiditis, surgical drainage revealed pus and led to the disappearance of septic episodes and ear, nose, and throat problems. There is an association between prolonged NT and NG intubation, and sinusitis or mastoiditis as an unrecognized source of sepsis in young infants. Absence of radiologic evidence of sinusitis or mastoiditis causes pitfalls in diagnosis and is related to delayed pneumatization of the sinuses and the mastoid in prolonged nasal intubation in young infants.

Bacterial Infections↗

Observations on temporal aspects of bone-conduction clicks: real head measurements.

To further elucidate nuances of bone-conduction (BC) stimulation, particularly as they may pertain to BC-elicited auditory brainstem responses (ABRs), real head measurements were made of vibratory responses to BC clicks. A miniature accelerometer was held firmly against the skull near a bone vibrator applied to the mastoid, to the opposite mastoid, and to the forehead. Measurements also were made with the vibrator applied to the forehead and the accelerometer placed on a mastoid. The measured vibrations were compared among conditions within and across subjects. The results demonstrate that vibration picked up in the immediate vicinity of the vibrator, roughly mimics the temporal and spectral characteristics of the click observed on an artificial mastoid. However, probing at sites remote to the bone vibrator suggested the introduction of a propagation-like delay as well as low-pass filtering. These findings support observations of previous researchers who demonstrated phase differences between vibrations recorded at different points on the skull, further demonstrating the complexities of skull vibration. Latency differences of ABR responses obtained with forehead versus mastoid placements, for example, cannot be attributed merely to the difference in efficiency between sites of stimulation demonstrated audiometrically. While the real head observations do not permit determination of the actual vibratory lag at the cochlea, they do permit the deduction that a comparable onset delay occurs in BC as in air-conduction stimulation via supra-aural earphones.

Acoustic Stimulation↗

The use of the temporoparietal fascial flap in temporal bone reconstruction.

After routine canal wall down mastoidectomy, local muscle flaps with and without bone paté, cartilage and fascia are the standard techniques available to otologists wishing to obliterate the mastoid and reconstruct the external auditory canal. Reconstructive options for temporal bone defects after extirpative surgery for cancer, osteoradionecrosis, and revision surgery for chronic granulomatous otitis media, however, are few. Although the neighboring temporoparietal fascia flap (TPFF), based on the superficial temporal vessels, has been frequently employed for auricular reconstruction, its versatility in temporal bone reconstruction has not been widely explored. The TPFF has recently been employed at our institution in 11 patients who presented with a variety of reconstructive problems, including defects after temporal bone resection, surgery for malignant otitis externa, and revision mastoid surgery. Follow-up in these patients ranged from 1 to 43 months (average 18.4 months) and surgical objectives of achieving a dry mastoid bowl, fully epithelialized canal, and/or reduction of mastoid cavity volume was attained in 100% of cases. The TPFF offers many advantages to the otologic surgeon when faced with reconstruction dilemmas that center around a poorly vascularized mastoid cavity and temporal bone. The TPFF is a reliable source of local well-vascularized tissue that is extremely pliable and facilitates both hearing and nonhearing preservation temporal bone reconstruction.

Adult↗

Value of computed tomography of the temporal bone in acute otomastoiditis.

In this study we report our experience with 24 patients with acute mastoiditis treated at the University Hospital in Ghent, Belgium. The most common presenting signs and symptoms of acute mastoiditis were an abnormal tympanic membrane (21/24), otorrhea (17/24) and earache (13/24). Postauricular edema and erythema with protrusion of the ear, often used as a diagnostic criterion, was present in only 3 patients. Demineralisation of the trabeculae was the most frequent radiological finding (13/24). Based on CT findings a distinction was made between two groups: acute incipient mastoiditis (13/24) and acute coalescent mastoiditis (5/24). Thirteen patients recovered with conservative therapy consisting of IV antibiotics and early myringotomy with or without placement of a ventilation tube. Mastoidectomy was required in 11 patients. Nine patients presented with a complication of infection extending beyond the mastoid compartment. The results are discussed and the value of CT scanning as a diagnostic tool and decisive element in the choice of therapy is analysed.

Acute Disease↗

[An osseointegrated micromanipulator as anchor for implantable hearing aid transducers. 1: Fitting to the surgical anatomy of the temporal bone and surgical technical properties].

The first electronic implantable hearing aids for patients with hearing loss are coupled to the ossicular chain or perilymph during implantation and are now available. Our new Tübingen implant designed for sensorineural hearing loss (SNHL) is the combination of an implantable microphone and piezotransducer. To avoid hearing losses during implantation, the Tübingen piezotransducer will be (1) fixed to the mastoid cavity and (2) positioned to one of the ossicular target points. This can be done with a micromanipulator which will be implanted together with transducer and microphone in the mastoid cavity. The manipulator weights 0.7 g. With four degrees of freedom, it allows highly secure and safe positioning of the transducer's probe tip to the ossicular chain under close to stereotactic conditions. The main advantages of the present micromanipulator are (1) easy handling during surgery, (2) the transducer's precise positioning to the ossicular target point with sufficient degrees of freedom, and (3) the transducer's stable fixation in the mastoid cavity in the final position. Following integrated safety as the leading principle, ossicular or inner ear injuries caused, e.g., by the patient's head movement or unintentional manual contact by the surgeon, are minimized. The micromanipulator is, as it were, the surgeon's vibration-free "artificial hand". The manipulator's development and its optimization to the mastoid cavity by test implantation in 50 human temporal bones are shown in detail. While coupling the transducer to the body of the incus, transducer, microphone, and micromanipulator can be implanted into 76% of all mastoid cavities without protrusion. In the case of transducers coupling to the long process of the incus, the protrusion-free implantation rate of the above-mentioned three implant modules is 78%.

Bone Plates↗

[Three years experience with ionomer cement in reconstructive middle ear surgery].

For nearly three years we have been using implants of polymaleinate ionomer in the reconstruction of the ossicle chain (Figure 1). Implants of this material can be easily formed by a diamond drill. An implant in site 18 months later is to be seen in Figure 2. From August 1990 through April 1993 this material has been implanted into 156 middle ears. Only one implant had to be explanted again for a second-look operation in cholesteatoma. Extrusion or any tissue reaction on the foreign substance could not be seen. The implant was examined histologically. It was covered by mucosa and not destructed anyway (Figure 3). According to the extension of a cholesteatoma we take away the dorsal wall of the ear canal for reasons of sanitation and leave a radical mastoid cavity in children. In adult patients we tend to reconstruct the ear-canal to avoid the disadvantages of a radical mastoid cavity: Frequent treatments and hearing-loss by resonance-shifting (2). For reconstructing the dorsal wall of the ear-canal cartilage of the concha and tragus is well qualified. In support of experimental and clinical experience of the Würzburg group (1) we take ionomer micro-implants for reducing large radical mastoid cavities (Figure 4). The radical mastoid cavity is finished by the diamond-drill before being filled up with micro-implant in the dorsal parts. The micro-implant is covered by a flap of periost and connecting tissue. Figure 5 shows a situation operated by this technique 20 months ago, Figure 6 shows the result after operation of a former secerning radical mastoid cavity.(ABSTRACT TRUNCATED AT 250 WORDS)

Biocompatible Materials↗

Tympanometry versus direct middle ear pressure measurement in an artificial model: is tympanometry an accurate method to measure middle ear pressure?

HYPOTHESIS: Indirect tympanometric pressure measurements of the middle ear (ME) do not correspond to direct pressure measurements. BACKGROUND: Tympanometry is an accepted method for estimating ME pressures. These pressure values are different, however, when measurements are made directly. MATERIALS AND METHODS: Negative pressures were induced by volume changes in an artificial ME model with various "mastoid" volumes. Both tympanometric and direct pressure measurements were obtained simultaneously. RESULTS: A substantial difference was demonstrated between tympanometric and direct pressure measurements. There was a linear correlation between tympanometry and direct pressures between -46.8 and -93.6 mmH2O, with a tympanometric overestimation of 40% to 20%, respectively. The smaller the "mastoid" volume, the greater the overestimation. The correlation was not linear for direct pressures between zero and -46.8 mmH2O. Tympanometric overestimation was greatest (i.e., 4-14-times the actual pressure) in the pressure range between zero and -12 mmH2O. CONCLUSIONS: Tympanometry does not yield precise ME pressure values. In a model with a larger "mastoid" and an actual pressure range of -46.8 to -93.6 mmH2O tympanometric readings are somewhat less unreliable (error of 40%-20%). However, tympanometry is in error of more than 400% in a model with a small mastoid in which the actual ME pressure is only slightly negative (i.e., range between -3.9 and -46.8 mmH2O). Therefore, this study implies that tympanometry has little use for measuring ME pressure especially in chronic ears or their sequelae that are usually characterized by having small negative pressures and small mastoids.

Acoustic Impedance Tests↗

Barotrauma vis-a-vis the "chronic otitis media syndrome": two conditions with middle ear gas deficiency Is secretory otitis media a contraindication to air travel?

We compared 17 patients (29 ears) with barotrauma with 171 patients suffering from "chronic ears" (secretory otitis media, atelectasis, or previously operated cholesteatoma). The patients with "chronic ears" were followed up prospectively, and none were found to suffer from barotrauma after flying on a commercial airplane. The mastoid pneumatization (seen on lateral mastoid radiographs) was significantly larger in ears with barotrauma, averaging 16.85 cm2, versus 12.9 cm2 in normal controls, whereas in "chronic ears" it was only 3.6 cm2. During flight on a commercial airplane, the middle ear has to equalize about 20% of its gas volume with the ambient pressure. This equalization must happen within 15 to 20 minutes of ascent and descent in order to avoid barotrauma. This 20% is a fivefold greater task for ears with a large mastoid pneumatization than for ears with an undeveloped pneumatization; "chronic ears" usually have an undeveloped mastoid pneumatization. The smaller the middle ear (mastoid) volume, the smaller the volume of gas needed to pass through the eustachian tube in order to equalize pressure changes during flying. This factor may explain why "chronic ears" rarely suffer from barotrauma. It also implies that eustachian tubes of secretory otitis, atelectatic, and cholesteatomatous ears have little problem in equalizing large pressure differences (over 2,000 mm H2O) within 15 to 20 minutes of landing, in contrast to what has been traditionally believed. Individuals with "chronic ears" can be advised that they can fly safely.

Adult↗

Isochronic mapping of the auditory brainstem response: normative results.

Isochronic mapping involves recording multi-channel evoked potentials from scalp electrodes and plotting contours of peak latencies. In this study, auditory brainstem responses were recorded from 20 electrode sites for left, right and binaural stimulation of each ear of 10 male and 10 female, normally hearing, young adults. Analysis of the data showed that the stimulus parameters of intensity, polarity and rate had no significant effect on the maps. On monaural stimulation, wave V was recorded first at the contralateral mastoid and ipsilaterally frontally and last at the ipsilateral mastoid some 350, mu s later. Binaural stimulation gave a symmetrical map, with wave V recorded first frontally and last at the occiput. In contrast, wave III was recorded first ipsilaterally and frontally and last at the contralateral mastoid. Wave II was recorded first at the rear of the contralateral mastoid and last forward of the ipsilateral mastoid. Comparisons between these results and human physiological studies are in agreement for waves V and III but do not support the concept of the VIIth nerve alone as the generator for wave II. These results suggest that this technique is a potentially useful diagnostic tool and it is intended to evaluate it by testing patients with a range of sensory, peripheral-neural and central-neural pathologies.

Audiometry, Pure-Tone↗

Measurement of middle ear volume using the impedance audiometer.

Ears with chronic otitis media are characteristically associated with small mastoid air cell systems. This also indicates a small air volume in these ears, which may influence the pathophysiology and course. Therefore, it may be important to get a measure of the air volume in the middle ear mastoid air cell system. Conventional mastoid X-ray investigations have so far been used for estimating this volume. As impedance audiometry has gained in popularity during recent years, it has been postulated that this tool may be useful for measuring the volume in the middle ear and the mastoid system. In this report we present data comparing the acoustically measured size to direct volumetric and planimetric size of the mastoid air cell system on the X-ray film. Temporal bone specimens with perforation of the tympanic membrane have been investigated. A good correlation between these methods is obtained, and we conclude that impedance audiometry enables a rapid and valuable estimation of the air reservoir in the middle ear.

Acoustic Impedance Tests↗

Intracranial complications following mastoidectomy.

Mastoidectomy is a common surgical procedure in otology. However, postoperative complications of various degrees of severity may occur. We present 4 children who underwent mastoidectomy for middle ear and mastoid disease and developed postoperative intracranial complications. One child was operated on for brain abscess 1 week after the initial mastoidectomy. Another child appeared with seizures 5 days after the initial mastoidectomy and a subdural empyema was drained during revision surgery. Large bone defects with exposed middle cranial fossa dura were found at revision surgery in both cases and Proteus vulgaris and methicillin-resistant Staphylococcus aureus were isolated from the mastoid and abscess cavities in these children. A small epidural collection was diagnosed in the third patient 2 days after initial mastoid surgery and was managed with intravenous antibiotics only. The other child was found to have sigmoid sinus thrombosis the day after mastoidectomy that was performed for nonresponsive acute mastoiditis. This child received both intravenous antibiotics and anticoagulants. Timely revision surgery, combinations of third- or fourth-generation cephalosporins with vancomycin or metronidazole and the addition of anticoagulants in cases of sinus thrombosis can lead to full recovery.

Adolescent↗

Tympanomastoidectomy. A 25-year experience.

Since 1956, 1,540 tympanomastoidectomy procedures for cholesteatoma or chronic suppurative otitis media with mastoiditis have been performed; 180, done from 1972 through 1980, were reviewed in detail for effectiveness of surgery, control of disease, and hearing results. The majority of the procedures were done for cholesteatoma. Almost all of these had preoperative sclerotic or poorly developed mastoids as judged by x-ray examination. A limited open-cavity technique with one-stage tympanic repair has resulted in long-term control of cholesteatoma in the mastoid segment in almost every case and reasonable success in control of middle ear disease and preservation or improvement in hearing. Properly performed modified radical mastoid cavities seldom cause problems in postoperative care, do not preclude swimming, and do not impair concomitant tympanoplastic repair. Failure to control disease in the middle ear or to improve hearing is the major problem. Revision tympanoplasty can correct some of these remaining problems, but is usually an elective procedure.

Adolescent↗

Further data about venous channels in South African Plio-Pleistocene hominids.

Original data about venous channels in South African Plio-Pleistocene hominids are discussed. To assess possible changes in blood volume flow of fossil hominids, we test whether dimensions of three extracranial venous foramina were different between Australopithecus africanus and Australopithecus (Paranthropus) robustus. Moreover, providing further data about the small sample of South African Plio-Pleistocene hominids, we also attempt to re-analyse the incidence of divided hypoglossal canals and four emissary foramina in a very large sample of extant African apes representing all ages, species and subspecies, in A. africanus and in "robust australopithecines". Up to now, only very poor data on extracranial dimensions of venous foramina were available for fossil hominids. However, this topic provides interesting information about the modifications of volume flow during human evolution. Assuming that in fossil hominids, as in humans, dimensions of condylar and mastoid foramina, as well as those of jugular foramina, depended on volume flow through them, we conclude, first, that volume flow through internal jugular veins was comparable in South African australopithecines, extant chimpanzees and humans, and second, that, in comparison with the extant less-encephalized chimpanzees (presumably reflecting the ancestral condition), volume flow was higher through condylar veins in A. (P.) robustus. This increase was responsible for a significantly greater amount of blood drainage from the brain (and consequently an increased arterial blood supply). We support the view that encephalization was the prevailing functional explanation for volume flow increase through condylar veins in A. (P.) robustus, in comparison with its ancestor with its presumably more ape-like degree of encephalization. Considering the incidence of emissary canals and foramina, significant differences between A. africanus, "robust australopithecines" and all the extant African ape species, were tested statistically. Concerning the condylar canal, we did not find differences between "robust australopithecines" and extant African apes. Concerning the incidence of divided hypoglossal canals, mastoid canals, parietal and occipital foramina, no difference was found between extant African apes, A. africanus and "robust australopithecines". High frequencies of either condylar or mastoid canals cannot be regarded as a "pongid condition". Moreover, we did not find convincing data to support the hypothesis that mastoid emissary veins (partly representing a putative "radiator" for cooling the brain) were selected in A. africanus, in comparison with "robust australopithecines".

Adult↗