Open Mastoid Cavity Research Articles

Experimental Studies on a New Highly Porous Hydroxyapatite Matrix for Obliterating Open Mastoid Cavities

In an initial preliminary study, the applicability of a new high-porosity hydroxyapatite (HA) ceramic for obliterating large open mastoid cavities was proven and tested in an animal model (bulla of guinea pig). Experimental study. NanoBone, a highly porous matrix consisting of 76% hydroxyl apatite and 24% silicone dioxide fabricated in a sol-gel technique, was administered unilaterally into the opened bullae of 30 guinea pigs. In each animal, the opposite bulla was filled with Bio-Oss, a bone substitute consisting of a portion of mineral bovine bone. Histologic evaluations were performed 1, 2, 3, 4, 5, and 12 weeks after the implantation. After an initial phase in which the ceramic granules were surrounded by inflammatory cells (1-2 wk), there were increasing signs of vascularization. Osteoneogenesis and-at the same time-resorption of the HA ceramic were observed after the third week. No major difference in comparison to the bovine bone material could be found. Our results confirm the favorable qualities of the new ceramic reported in association with current maxillofacial literature. Conventional HA granules used for mastoid obliteration to date often showed problems with prolonged inflammatory reactions and, finally, extrusions. In contrast to those ceramics, the new material seems to induce more osteoneogenesis and undergoes early resorption probably due to its high porosity. Overall, it is similar to the bovine bone substance tested on the opposite ear in each animal. Further clinical studies may reveal whether NanoBone can be an adequate material for obliterating open mastoid cavities in patients.

Rekonstruktion der Gehörgangswand mit Knochenchips aus der Temporalschuppe - Erste Ergebnisse

The canal wall down-technique in cholesteatoma surgery with the creation of an open mastoid cavity offers many disadvantages as prolonged healing time, necessity for periodic cleaning and subsequent infections. Therefore reconstruction of the posterosuperior canal wall is the more and more preferred technique to restore the physiologic anatomy of the external auditory canal without lacking a good surgical exposure to the tympanal and retrotympanal spaces. Cartilage is the mainly used material for this technique, as cartilage is easy to prepare and to fit into the defect with good viability. However, cartilage resorption and retraction is observed increasing the risk for recurrent cholesteatoma. In contrast, by the use of bone chips from the temporal squama a stable and close restoration of the auditory canal wall can be achieved. In 23 patients (17 attic and 6 sinus cholesteatomas including two recurrences in each group) we have performed an anterior atticoantrostomy with retrograde cholesteatoma removal and reconstructed the posterosuperior wall of the auditory canal with bone chips harvested from the temporal squama by chisels. The bone chips and remaining gaps in the reconstructed wall were covered by bone paté and temporal fascia. In 4 cases the ossicular chain could be conserved (type-1 tympanoplasty [TP]), type-3 TP with PORP was performed in 13 and TORP-TP in 6 cases. The mean follow-up was 12.1 months (range 4 - 34 months). 8 patients had undergone a second-look procedure. On follow-up all patients showed a good healing of the external ear canal with no graft insufficiency. In one case we observed a slight ear canal narrowing due to bone excess, three patients developed retraction pockets of the attic. Recurrent cholesteatoma was not seen yet. Second-look tympanotomy revealed complete ingrowth of the transplanted bone chips into the surrounding bony structures in all cases. One residual cholesteatoma had to be removed and the canal wall had to be reconstructed again with bone chips. The average postoperative air-bone gap was 7.0 +/- 8.2 dB HL for type-1 TP, 8.6 +/- 3.0 dB HL for PORP-TP (83 % [100 %] of the patients < or = 10 dB HL [< or = 20 dB HL]) and 19.3 +/- 9.2 dB HL for TORP-TP (66 % of the patients < or = 20 dB). Osteoplastic atticoantrostomy allows adequate anatomic and physiologic restoration of the auditory canal even after extensive cholesteatoma removal. Bone stability may reduce recurrent cholesteatoma. However, due to the underlying impaired tubal function long-time results must be further evaluated.

Should Ossicular Reconstruction Be Staged Following Tympanomastoidectomy

To determine whether ossicular reconstruction (OCR) performed concurrent with tympanomastoidectomy for cholesteatoma results in significantly different hearing results when compared to OCR performed in a separate, staged procedure. Retrospective. Study subjects were patients undergoing OCR within a 2-year period. Intervention was OCR concurrent with tympanomastoidectomy for cholesteatoma (group 1) or staged following tympanomastoidectomy for cholesteatoma (group 2). Main outcome measures were mean postoperative air-bone gap (ABG), proportion achieving ABG closure to <20 dB and <30 dB for group 1 and group 2 overall and when controlling for type of mastoid cavity created (open or closed) and the status of the stapes suprastructure (TORP vs. PORP OCR). Eighty-three patients were identified. Forty underwent OCR concurrent with tympanomastoidectomy and 43 underwent a staged OCR after tympanomastoidectomy. Overall, similar hearing results were seen in the two groups. When considering the status of the stapes and mastoid cavity, concurrent OCR resulted in improved mean postoperative ABG in a closed mastoid cavity with an intact stapes suprastructure (P = .024). Furthermore, a greater proportion of patients who had concurrent OCR within this group achieved ABG <20 dB and ABG <30 dB, although this difference did not reach statistical significance (P = .092 and P = .078, respectively). By contrast, staged OCR resulted in improved mean postoperative ABG and ABG <30 dB in open mastoid cavities with an absent stapes suprastructure (P = .040, and P = .019, respectively). Similarly, a greater proportion achieved ABG <20 dB, approaching statistical significance (P = .055). Staged OCR is advantageous in those with most severe disease, whereas those with least severe disease may benefit from a concurrent OCR.

か牛骨迷路欠損を伴う慢性中耳炎例

We reported a rare case of bony destruction of the tympanic promontory in suppurative otitis media without cholesteatoma. A 62-year-old male consulted the hospital in October 2002, with complaints of impaired hearing, otorrhea, dizziness and facial palsy on the right side. Hearing in the right ear was totally gone. CT showed a defect in the cochlear bony wall with abundant soft density tissue in the middle ear cavity, antrum and mastoid cavity. Surgery was performed. The bony structure in the cochlear lower basal turn had been destroyed and membranous labyrinth was confirmed when granulation was removed. The defect was then covered with fascia and an open mastoid cavity was created. The facial nerve was also exposed. The patient showed a good postoperative course: facial nerve palsy improved to normal, dizziness and nystagmus disappeared, but deafness was irreversible.Generally, in a case of cholesteatoma, bony destruction is more frequent than in a case of suppurative otitis media and labyrinthine or facial canal dehiscence is a rather common finding. This case report showed that even in the absence of cholesteatoma, these degenerative changes could develop in suppurative otitis media and could extend to the tympanic promontory and facial canal.

Dimensional stability of the free fascia grafts: a human study.

In animals it has been shown that autologous free fascia grafts (fascia lata and temporal fascia) change dimensions during the vital first 5 days of healing. Poor dimensional stability of these grafts can be an important reason for failure of complete closure of tympanic membrane perforations in tympanoplasty operations, particularly in large perforations. Dimensional stability of these fascias has been studied in humans. Prospectively, 11 patients were studied. Patients who were subjected to open mastoid cavity surgery were included in the study. The mastoid cavity was exteriorized, and the fascia graft was used to seal the perforation and cover a part of the bare mastoid bone in the routine way. At this stage, equally cut pieces of temporal fascia and fascia lata were laid on the remaining part of the bare mastoid bone. The mastoid cavity was then packed with Gelfoam and wound sutured. The pieces of graft material under study were removed after 5 days, leaving the graft used to seal the tympanic membrane perforation undisturbed. The harvested grafts were measured for their dimensional variations, if any. It was observed that free autologous temporal fascia grafts exhibited poor dimensional stability as compared with free autologous fascia lata grafts. Poor dimensional stability of free temporal fascia grafts as seen in animals was confirmed in the present human study. This poor dimensional stability of temporal fascia grafts might be contributing to failure of closure of tympanic membrane perforations in tympanoplasty.

Vertigo in suction of open mastoid cavities ("radical surgery cavities")

Vertigo during suction-cleaning of open mastoid cavities is caused by cold stimulation of the vestibular organ. In clinical and model-experimental measurements we tried to estimate the physical background and the dimension of this temperature drop. Using different techniques like thermo-probes, thermovision, or additional model experiments temperature changes during suction were measured in 5 volunteers with open mastoid cavities. These registrations were carried out with special regard to the moisture of the cavity-walls. Distinct temperature changes during suction were observed. In moist cavities superficial temperature decrease was much higher than in dry ones. Using additional model experiments, temperature conduction towards e.g. the horizontal semicircular canal could be simulated. Among other mechanisms like replacement of sucked-off air by colder air, or taking away warm air close to the cavity walls, effects of evaporative cold seem to be very significant. This could be demonstrated by moistening cavity walls in patients as well as in model experiments. The conclusion to keep the cavity walls as dry as possible is already a clinical demand. In this paper, the physical background and the dimensions of thermal effects during suction-cleaning could be elucidated.

Probe-Tube Microphone Measures in Patients with Open-Mastoid Surgery: Real-Ear-to-Coupler Differences and Real-Ear Unaided Responses

Real-ear-to-coupler differences (RECDs) and real-ear unaided responses (REURs) were measured using a probe-tube microphone system in 15 patients who underwent open mastoid surgery. The results show that RECDs are significantly smaller at higher frequencies (1.5, 2.0, 3.0, 4.0 and 6.0 kHz) in mastoid ears. The intrasubject variability of RECDs measures in these patients is on average 2.6 dB larger than for controls. For REURs, mastoid surgery significantly reduced the mean peak resonant frequency without affecting the amplitude and bandwidth. In operated ears, mean resonant frequency is by a factor of 1.4 lower than that for normal ears. Reduced responses (negative gains) at frequencies above the resonance peak occurred in 7 out of the 15 patients. These reduced responses corresponded to the smaller RECD at the middle and high frequencies. The results support the need for individual RECD measures to be made in operated ears instead of using average values from normal subjects. Otherwise, real-ear measures of the aided response should be made for each patient with open-mastoid cavity and the fitting should be done in terms of the target response at the eardrum rather than by defining a target insertion gain.

Cholesteatoma in children—the experience at The Red Cross War Memorial Children’s Hospital in South Africa 1988–1996

This review of experience with cholesteatoma in children, describes the presentation and features of the disease from a tertiary institution in a ‘developing country’. A total of 24 out of 96 cholesteatomas in 81 children (M:F=44:37) aged 2–12 years initially presented with mastoiditis, with intracranial complications in seven children. Three of the cholesteatomas were congenital, 56 arose from retraction pockets—11 pars flaccida, 45 pars tensa—21 were associated with either a central perforation or total atelectasis and one originated at a ventilation tube site. Open cavity surgery was undertaken in all cases—atticotomy in 14, open mastoid cavity in 82 ears. It was not always possible to preserve reasonably normal pre-operative hearing nor was it possible to improve hearing loss. Twenty-six out of 81 children did not return for follow-up. Even with open cavity surgery, recurrence of cholesteatoma occurred. Late diagnosis, extensive disease, a high rate of complications and poor follow-up are the features of this disease in ‘developing’ countries.

Cochlear implant after reconstruction of the external bony canal wall and tympanic cavity in radically mastoidectomized patients with cholesteatoma

One of the postoperative complications of cochlear implants in patients, who previously received radical mastoidectomy, is an exposure of electrode by breakdown of thin epithelium in the open mastoid cavity. To avoid such complications, in the first stage, radical mastoidectomy with the reconstruction of the posterior bony canal wall and mastoid obliteration with bone chips and plates and the creation of the new tympanic cavity, were performed. One or 3 years later, implantation of a 22-channel cochlear implant, as the second stage procedure, was successfully performed in three patients with profound sensorineural hearing loss, due to cholesteatoma in the side of the ear in which cochlear implantation was indicated. The advantages of this technique are as follows: (1) Electrode is protected from the cavity problems, such as chronic infection or erosion of the epithelium in the open mastoid cavity; and (2) reconstruction of the new tympanic cavity and tympanic membrane is beneficial for avoidance of electrode exposure in the mastoid and tympanic cavity.

The use of hydroxyapatite granules in mastoid obliteration.

The problems of open radical mastoid cavities are well known. One of the ways to manage such problems is obliteration of the mastoid cavity. Most biological materials, such as muscle flap or bone chips/paste, tend to be resorbed with time, resulting in reformation of the cavity. The author reports a series of 34 mastoid obliteration operations using hydroxyapatite granules and an inferiorly based periosteal flap. The follow-up period was between 1 and 5 years. The obliterated cavities remained small, stable and trouble-free. Water was tolerated in the cavities allowing most patients to enjoy water sports. Only one patient had permanent discharge due to incomplete epithelialization of the obliterated cavity.

Long-term results of mastoid cavities grafted with cultured epithelium prepared from autologus epidermal cells to prevent chronic otorrhea.

Chronic otorrhea and recurrent infection from open mastoid cavities are common and troublesome clinical problems for which there is no very satisfactory treatment. The authors have previously described a simple procedure to solve this problem, using autologous cultured keratinocyte layers grafted onto the unepithelialized open mastoid cavities. All procedures are carried out on an outpatient basis without anesthesia, except for local anesthesia for the skin biopsy. Twenty-six patients with 28 "difficult" mastoids, in which otorrhea had been present from 2 to 32 years, have been grafted with a follow-up period varying from 10 to 18 months. Seventeen mastoid cavities became symptom-free as a result of this technique. There were 4 failures, and partial success was shown in 7 cavities as judged by both the patient and by clinical examination.

Ein Beitrag zur Klinik und Histopathologie der Mittelohrtuberkulose*

During the past few decades the clinical features of middle ear tuberculosis have changed. Hence, clinical differentiation between tuberculous and non-specific proliferative otitis media and mastoiditis is now difficult. Between 1986 and 1992 five cases of tuberculous otitis media were treated surgically in the ENT-Dept. of the University of Hamburg, representing 0.2% of all performed middle ear operations. According to our experience the therapy of choice is the open mastoid cavity with subsequent chemotherapy to avoid recurrent infections. The advantages of this procedure are proven by actual histopathological findings as well as by the analysis of historical microsections of the Wittmaack temporal bone collection: according to these findings, two different types of histopathological alterations can be differentiated.

外耳道削除後の乳突腔に発生する諸問題

Mastoid cavity problems were studied in 113 ears that had the posterior canal wall removed during surgery (open tympanoplasty, radical mastoidectomy, modified radical mastoidectomy) for middle ear cholesteatoma. Posterior canal wall reconstruction with mastoid obliteration was performed in 19 ears, mastoid obliteration only in 10 ears, and no treatment for the open mastoid cavity in 84 ears.The total incidence of mastoid cavity problems was 30.1%. Aural discharge was most frequently observed (24.8%). Other problems included postoperative development of mastoid air cells, cholesteatoma or cyst formation, the absorption of the reconstructed canal wall, and mycosis. Cavity problems were more frequently observed in the groups with reconstruction or obliteration because of the absorption of those materials. Patients under 9 years old frequently had cavity problems, and additional surgery was performed in 44.1%.Preservation of the canal wall is most important in preventing the cavity problems, and firm obliteration of the open mastoid cavity with bone tissue or ceramics is necessary in patients that have the canal wall removed.

The acoustics of the open mastoid cavity (so-called "radical cavity") and its modification by surgical measures. II. Clinical studies

The acoustic resonance of a severely altered outer ear channel (radical mastoid cavity) is investigated in a series of 18 patients who underwent revision surgery by means of in-situ measurements of the sound-pressure-level near the tympanic membrane. While the average volume of the open cavity differs from the normal ear channel for the factor 2.5, the size of the external meatus is--in average--only 20% larger. This leads to an average frequency in patients with open cavity of 1939 Hz, more than 1000 Hz less than in a series (n = 20) of normal ears (average resonance frequency: 2942 Hz). The altered acoustic behaviour of the open cavity leads to partial extensive discrepancies of the resonance-caused sound-pressure augmentation in the frequencies of 3 and 4 kHz, which are important for speech perception. The average difference is more than 10 dB (SPL). Proved surgical techniques of cavity obliteration and meatoplasty can lead to a nearly normalized acoustic behaviour of the outer ear in a statistic significant way. Due to these surgical procedures, an average postoperative resonance frequency of 2421 Hz could be reached in our patients. Especially, the resonance-caused sound-pressure augmentation in 3-4 kHz could nearly be equalized to such of a normal outer ear. Differences in the acoustic behaviour of the outer ear as can be found between patients with an open mastoid cavity and normal ears can almost be eliminated surgically.(ABSTRACT TRUNCATED AT 250 WORDS)

Mastoid Cavities Grafted With Cultured Epithelium Prepared From Autologous Epidermal Cells to Prevent Chronic Otorrhea

At the 1991 annual meeting of the Triological Society held in Waikoloa, Hawaii, D. J. Premachandna, FRCS, on behalf of coworkers from Sussex and Tunbridge Wells, England, presented results of managing chronic otorrhea from mastoid bowls. This technique utilized autologous keratinocyte layers cultured from a 4 X 8-mm postauricular skin graft from the patient. Skin was cultured for 9 to 21 days and placed on one side of mesh gauze used as a carrier. This was draped over the area of granulation tissue, which had previously been prepared with bizmuth and iodoform gauze packing. Results were reported in 26 patients with 28 open mastoid cavities; chronic otorrhea was present for 2 to 32 years. Follow-up ranged from 10 to 18 months. Complete epithelialization occurred in 17 cavities and partial epithelialization in seven cavities. There were four failures including one cholesteatoma recurrence. The authors felt that advantages with this technique included

Mastoid obliteration with the temporoparietal fascia flap

Obliteration of persistently discharging open mastoid cavities is one surgical option to achieve a dry ear. All the currently described techniques involve the use of random pattern local tissue flaps or free grafts. Ten patients have undergone obliteration procedures using the vascularized temporoparietal fascia flap. This resulted in rapid epithelialization by six weeks in seven out of 10 cases. The remaining three patients have persistent non healed areas over the medial attic wall, but are not troubled by otorrhoea. The indications, technique and complications of mastoid obliteration by this axial pattern flap are described.

Pinch Grafting of the Open Mastoid Cavity

Secondary pinch skin grafting was performed on the mastoid cavities to promote healing of the mastoid wound after ear surgery using the open technique. Pinch grafts (multiple small grafts of the epidermal layer) were transplanted in 20 patients, soon after the mastoid cavities were covered with healthy granulation tissue in a mean of 28.5 days after the initial surgery. The grafts adapted well in 18 of the 20 patients. Epidermization was complete in a mean of 11.1 days after grafting, that is, within 40 days after the initial ear surgery. On the other hand, epidermization in 10 cases without grafting was completed in a mean of 83.3 days after the ear surgery. Thus, the pinch grafts reduced healing time by more than 40 days. The secondary application of pinch grafting was beneficial for healing of exposed mastoid cavities caused by use of the open technique tympanoplasty or radical mastoidectomy.

Lufttemperatur im äußeren Gehörgang - experimentelle Untersuchungen in bezug auf die Radikalhöhlen-Chirurgie*

By means of special probes, air temperatures were determined in external auditory meatus and in "radical" mastoid cavities. Under normal conditions, there was no difference between the two groups, the temperature next to the drum head being in the same range as the body temperature. Exposure to simulated wind only lowered the temperature significantly in cases with very wide external meatus; e.g., after surgery. Suction--as is used in the daily practice of cleaning ears in the ENT surgery--caused a very abrupt decrease in temperature. In cases with open mastoid cavities, there was vertigo with nystagmus, due to the caloric vestibular stimulus. -Operative techniques such as the obliteration of such cavities or the reconstruction of the posterior wall of the meatus can considerably reduce this phenomenon.

Treatment of postoperative otorrhoea by grafting of mastoid cavities with cultured autologous epidermal cells

Autologous cultured keratinocyte layers were grafted onto the unepithelialised open mastoid cavities in 8 patients with otorrhoea for 2 to 32 years. All procedures were done on an outpatient basis without anaesthesia, except for local anaesthesia for skin biopsy. The cultured keratinocyte layers adhered well to the bed of granulation tissue lining the mastoid cavity and formed an excellent protective covering of stratified squamous epithelium. All 8 patients have been free from otorrhoea for the 2 to 6 months since grafting.

Medical management of active chronic otitis media: A controlled study

About 2 per cent of adults have active chronic otitis media, the majority being managed by medical means. Previous controlled studies have been unable to show benefit from any medication, including systemic or topical antibiotics, but the effect of the addition of topical steroids to the latter has never been evaluated. One hundred and sixty three adults with active chronic otitis media were randomly allocated to receive either antibiotic/steroid ear drops or placebo therapy over a 4-6 week period. Fifty-two per cent of ears receiving active therapy, as opposed to 30 per cent on placebo therapy (p less than 0.05), became otoscopically inactive if compliance to medication was greater than 70 per cent. However, when there was an open mastoid cavity, active therapy was no more successful than placebo. Though gentamicin was the antibiotic used, there was no evidence of ototoxic inner ear damage. Surprisingly, correlation between clinical activity and patient report of a discharge was poor. Forty per cent of both treatment groups considered that their ear had become dry following therapy and these were not the same patients whose ears had become otoscopically inactive.