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PubMed2006

Further application of the bilobed flap: the split bilobed flap for reconstruction of composite posterior auricular and mastoid defects.

In this article a modified bilobed flap from mastoid and lateral neck skin for reconstruction of complex defects of the posteromedial surface of the auricle and mastoid skin, with the preservation of the retroauricular sulcus, is described. Reconstruction of the postero-medial auricular surface has almost never been a concern for reconstructive surgeons. It is in fact a shaded area with little aesthetic relevance and direct closure, skin grafting and even secondary healing are used for skin cancer defects repair. Also mastoid skin defects can be repaired with simple techniques such as skin grafts or transposition flaps from the remaining mastoid skin or from the neck. On the other hand, cancers involving the postero-medial auricular surface, the retroauricular sulcus and the mastoid skin require wide and deep resections that involve the posterior auricular muscles and reach the perichondral and periosteal surfaces. Direct closure with undermining, if feasible, will obliterate the retroauricular sulcus causing asymmetry with the contralateral ear and, if defects are cephalad will impair the possibility of wearing spectacles, thus leaving functional and aesthetic impairment. Transposition flaps from the remaining mastoid skin, due to the lack of skin laxity, are not feasible because the donor site cannot be closed. Two patients, both affected by basal cell carcinoma involving the posteromedial auricular surface and the mastoid skin have been treated with this flap. In both cases the use of the modified bilobed flap described in this article allowed preservation of the retroauricular sulcus and closure of the donor site. Scars were hidden along minimal tension lines and the possibility of wearing spectacles along with sensitivity all over the reconstructed area were maintained.

Aged↗
PubMed2000

Acute mastoiditis in children: review of the current status.

BACKGROUND: acute mastoiditis is the most common intratemporal complication of otitis media. Its management is still a challenge due to potentially serious consequences. This study was designed to evaluate the recent experience with pediatric acute mastoiditis at our institution and to determine if the incidence of this entity is changing over time. MATERIAL AND METHODS: retrospective review of records of children with acute mastoiditis treated at the hospital of the Medical School at the University of Porto, Portugal, between July 1993 and June 1998. Criteria for the diagnosis of acute mastoiditis were postauricular swelling and erythema, protrusion of the auricle, and evidence of co-existent or recent otitis media. RESULTS: 43 patients fulfilled the entry criteria. Most were boys (69%). Ages ranged from 8 months to 14 years and 4 months; infants represented 40% of the total. Acute mastoiditis was the first recognized sign of otitis media in 48% of patients. More recent years of the study saw an increase in the number of children referred with acute mastoiditis. Upon admission, 56% were under antibiotic treatment, with an average intake of 5.8 days. All patients were hospitalized; 26 cases recovered after intravenous antibiotics plus myringotomy, and the rest required an additional surgical procedure. The most common organisms recovered from cultures were Streptococcus pneumoniae and Streptococcus pyogenes. In our series, associated complications occurred in 13.9%; facial paralysis in one, and involvement of the central nervous system in five. CONCLUSIONS: pediatric acute mastoiditis continues to be a potentially dangerous infection in the antibiotic era. The incidence of this complication may be increasing recently in the community studied. Great care is required of clinicians to reach an early diagnosis in order to promote adequate management and prevent inherently severe complications.

Acute Disease↗
PubMed2001

Acute mastoiditis--the antibiotic era: a multicenter study.

OBJECTIVES: To evaluate the clinical course and identify the causative organisms of acute mastoiditis in a community where most of the patients who develop acute otitis media are treated with antibiotics. METHODS: A multicenter retrospective review of a series of 223 consecutive cases of acute mastoiditis. SETTING: Nine secondary or tertiary academic or non-academic referral centers. RESULTS: Prior to the diagnosis of acute mastoiditis, 121 of the patients (54.3%) had been receiving oral antibiotic treatment for acute otitis media for periods ranging from 1 to 21 days (mean 5.3 days). Samples for bacterial culture were obtained from 152 patients. Cultures were negative in 60 patients. The organisms isolated in the 92 positive cultures were: Streptococcus pneumoniae (15 patients), Streptococcus pyogenes (14 patients), Staphylococcus aureus (13 patients), Staphylococcus coagulase negative (three patients), Pseudomonas aeruginosa (eight patients), Haemophilus influenzae (four patients), Proteus mirabilis (two patients), Escherichia coli (two patients), Klebsiella pneumoniae (one patient), Enterobacter (one patient), Acinetobacter (one patient), anaerobic gram-negative bacilli (one patient), and fungi (two patients). Ten patients had mixed flora. Sixteen patients presented with complications (cerebellar abscess, perisinus empyema, subdural abscess or empyema, extradural abscess, cavernous sinus thrombosis, lateral sinus thrombosis, bacterial meningitis, labyrinthitis, petrositis, or facial nerve palsy). CONCLUSIONS: Antibiotic treatment cannot be considered an absolute safeguard against the development of acute mastoiditis. Early myringotomy for acute otitis media seems to decrease the incidence of complications. The distribution of causative organisms in acute mastoiditis differs from that in acute otitis media. Intracranial complications in acute mastoiditis are not rare. Because of the diversity of causative organisms in acute mastoiditis and the growing resistance of bacteria to the various antibiotics, all means to obtain a sample for culture prior to antibiotic treatment, including general anesthesia.

Acute Disease↗
PubMed1999

Impact of resistant pneumococcus on rates of acute mastoiditis.

OBJECTIVE: To determine whether the rate of acute mastoiditis is rising, specifically as a result of antibiotic-resistant strains of Streptococcus pneumoniae. METHODS: A retrospective chart review of all patients with a discharge diagnosis of acute mastoiditis between July 1, 1987, and June 30, 1997, was performed at our academic, tertiary-care medical center. There were no interventions, and the main outcome measures included the number of cases of acute or coalescent mastoiditis, stratified by pathogen, per year. RESULTS: The rate of acute mastoiditis as a proportion of yearly otorhinolaryngology admissions increased linearly over time (P = 0. 024). Pneumococcal-related rates of acute mastoiditis, expressed as a proportion of yearly hospital and otorhinolaryngology admissions, increased linearly over time (P = 0.002, P = 0.002). All but 1 case of pneumococcal mastoiditis during the past 3 years were caused by penicillin-resistant strains. CONCLUSIONS: The emergence of antibiotic-resistant S pneumoniae may be responsible for an increasing rate of acute mastoiditis.

Acute Disease↗
PubMed1999

Acute mastoiditis in children: is surgical treatment necessary?

Acute mastoiditis in children remains an otological problem. Although the widespread use of antibiotics has reduced the need for surgical intervention, surgery is frequently used in the treatment of acute mastoiditis and its complications. The charts of 44 patients hospitalized with signs of acute mastoiditis were reviewed. In 43.2 per cent of all patients, acute mastoiditis was the presenting sign of acute middle-ear infection. Post-auricular erythema and protrusion of the auricle were the most frequent signs at presentation. All four signs (post-auricular erythema, oedema, tenderness, and protrusion of the auricle) were present in 40.9 per cent of patients. No bacterial pathogen was isolated in 45.5 per cent of ear cultures. Complicated acute mastoiditis was diagnosed in 13.7 per cent of the patients. Eighty-seven per cent of patients responded well to intravenous antibiotics and myringotomy, and in 11.4 per cent mastoidectomy or abscess drainage were performed. We conclude that nearly all patients with uncomplicated mastoiditis recover following intravenous antibiotics and myringotomy. Mastoidectomy should be performed in selected cases, such as cases of complicated acute mastoiditis.

Acute Disease↗
PubMedDate not supplied

Mastoid obliteration by BMP-2/collagen composites: an experimental study using tissue engineering.

PURPOSE: Several materials have been used in the application of mastoid cavity obliteration during surgery for cholesteatoma; however, nothing has won universal acceptance. Through the advancement of tissue engineering, bone morphogenetic protein-2 (BMP-2)/collagen composites have been elucidated as inducers of heterogenic bone formation. This study was performed to investigate whether these composites are potentially obliteration materials for use in the mastoid cavity by using an animal experimental study. MATERIALS AND METHODS: The composites were implanted in the rat mastoid to investigate whether new bone would be tissue engineered in the mastoid and, if so, whether the newly formed bone was stable. The composites were examined histologically over a 24-week period. RESULTS: The composites implanted in the rat mastoid were able to tissue engineer new bone, and the newly formed bone was stable as assessed histologically, with almost normal bone structure, that was not resorbed during the 24-week period. Adverse immunological reactions were not found during our observation. CONCLUSIONS: Bone that was tissue engineered by the BMP-2/collagen composites was stable as assessed by histological examination and persisted in the rat mastoid. The present study shows that the composites have the potential to become real materials for use in mastoid obliteration.

Animals↗
PubMed1998

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

OBJECTIVES: To clarify mastoid pneumatization in children with congenital cholesteatoma and compare their clinical characteristics. STUDY DESIGN: The mastoid pneumatization of 34 children with congenital middle ear cholesteatoma, of 34 age-matched children with unilateral acquired cholesteatoma, and of 17 age-matched control children without middle ear diseases was studied. METHODS: The sizes of the mastoid cells were measured from 1.5-mm sliced semiaxial sections of a temporal bone computed tomography scan. The sum of the two areas from the two images, one showing the lateral semicircular canal and the other, 3 mm below this, was defined as the area of the pneumatized mastoid cells. RESULTS: The mastoid cells in ears of children with congenital cholesteatoma were poorly pneumatized compared with those of control children without middle ear diseases, but were better pneumatized compared with those of children with acquired cholesteatoma. In children with congenital cholesteatoma, the degree of pneumatization in the cholesteatoma side was significantly poorer than that in the opposite side. A well-pneumatized mastoid was seen in ears with no episode of otitis media, in ears with the open-type cholesteatoma, and in ears with ossicular anomalies. CONCLUSIONS: The presence of cholesteatoma matrix accelerates the inflammatory response when middle ear infections occur, and this probably leads to the suppression of mastoid pneumatization. The authors also propose the hypothesis that cholesteatoma in most congenital cases is the open type, and that middle ear inflammation may contribute to the formation of cystic and closed-type cholesteatoma.

Adolescent↗
PubMed2000

Structural changes and protein expression in the mastoid bone adjacent to cholesteatoma.

OBJECTIVE: Cholesteatoma of the mastoid and middle ear causes erosion of nearby bone. In this study we examined the mastoid bone adjacent to cholesteatoma and compared it with normal mastoid bone. In particular, noncollagenous proteins, which have a special structural and functional role in bone, were addressed. STUDY DESIGN: Nine mastoid specimens with cholesteatoma and four normal specimens obtained at surgery were examined. METHODS: Histological and immunohistochemical methods were employed to evaluate the nature of structure and noncollagenous protein content changes in the mastoid bone affected by cholesteatoma. RESULTS: The bone associated with cholesteatoma had structural changes as a noncontinuous periosteum, empty lacunae, irregular cement lines, and, specifically, the appearance of eosinophilic vesicles at the interface between the bone and cholesteatoma Immunohistochemistry demonstrated that noncollagenous proteins were apparently absent in the affected mastoid bone. Bone remote from the cholesteatoma seemed normal. CONCLUSIONS: These findings demonstrate for the first time the changes in the noncollagenous protein content in the mastoid bone affected directly by cholesteatoma These changes could be a result of a direct influence of cholesteatoma-derived products on the osteoblast.

Adolescent↗
PubMed2001

Acute mastoiditis in children: a seventeen-year experience in Dallas, Texas.

BACKGROUND: In the preantibiotic era acute mastoiditis was the most common complication of acute otitis media, often resulting in substantial morbidity and mortality. Since 1989 several investigators have documented an increased frequency of acute mastoiditis in children. METHODS: The medical records of all children with a discharge diagnosis of acute mastoiditis, managed at Children's Medical Center, Dallas, TX, from 1983 through 1999 were reviewed. RESULTS: There were 57 cases of acute mastoiditis during the 17-year period of 1983 through 1999 compared with 57 cases in a 25-year period of 1955 through 1979 reported previously at the same institution. The number of cases of acute mastoiditis per 10,000 hospital admissions increased significantly (regression analysis P = 0.003) during the more recent 17 years. From 1993 through 1999 there were 4.5 cases or more per 10,000 admissions each year, whereas from 1983 through 1992, the incidence never exceeded 4.3 cases per 10,000 admissions (P = 0.018). The median age of the patients was 48 months. Twenty-two patients (38.5%) were younger than 24 months; 17 of these were 12 months of age or younger. Twenty-two (38.5%) patients had no history of previous episodes of acute otitis media. Streptococcus pneumoniae was the pathogen most often isolated from the cultures. Complications of mastoiditis occurred in 20 children (35%). CONCLUSIONS: We conclude that acute mastoiditis continues to be a problem in the post antibiotic era. It occurs mainly in young children and can be the first evidence of ear disease.

Acute Disease↗
PubMed2004

The use of demineralized bone matrix for mastoid cavity obliteration.

OBJECTIVE: To evaluate the use of demineralized bone matrix as a graft material for mastoid cavity obliteration in the treatment and prevention of problematic mastoid cavities. STUDY DESIGN: The study is a retrospective review of patients identified using a computerized otology database. SETTING: Tertiary care referral center. PATIENTS: Patients were included in this study if they underwent mastoid obliteration using demineralized bone matrix. INTERVENTION: Mastoid obliteration was performed for revision of a problematic mastoid cavity (n = 8) or primarily after canal wall down mastoidectomy for recurrent cholesteatoma (n = 3). MAIN OUTCOME MEASURES: Data were collected to evaluate the ability to achieve a dry ear canal. Postoperative healing time and hearing results were also assessed. RESULTS: A dry ear canal was achieved in all patients with a follow-up of 6 to 20 months (average, 14.5 mo). Eight patients (73%) had a well-healed, dry ear canal by their first postoperative visit (9 wk). One patient required 12.5 weeks to heal. Two patients (18%) had more prolonged granulation at the ear canal incision, which resolved in 17 and 28 weeks, respectively. The average preoperative pure-tone average air-bone gap was 47 +/- 14.9 dB (mean +/- SD), compared with postoperative values of 27.6 +/- 12.8 dB (p = 0.0033; paired t test). This represents an average pure-tone average air-bone gap closure of 20 dB. CONCLUSION: The use of demineralized bone matrix as a graft extender in mastoid obliteration allowed creation of a dry, smooth-contoured canal in all patients studied. A significant improvement in hearing was also obtained. Demineralized bone matrix is an acceptable graft alternative for mastoid obliteration.

Adolescent↗
PubMed2004

Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy.

OBJECTIVE: To describe an effective technique for mastoid cavity obliteration in canal wall down tympanomastoidectomy for chronic otitis media and review its efficacy in producing a dry, low-maintenance, small mastoid cavity. DESIGN: : Retrospective clinical study of a consecutive series of procedures from 1995 to 2000. SETTING: Tertiary referral center and institutional academic practice in otology and neurotology. PATIENTS: Sixty consecutive procedures for active chronic otitis media with a minimum follow-up of 12 months (mean, 31 mo; range, 12-80 mo). INTERVENTION: All patients had canal wall down mastoidectomy with simultaneous tympanoplasty including split-thickness skin grafting. An inferiorly pedicled, periosteal-pericranial flap was used in conjunction with autologous bone pate to obliterate the mastoid cavity. The additional length provided by the pericranial extension of the flap permitted it to reach superior to the lateral canal and into the sinodural angle, with improved coverage of bone pate and better reduction of cavity size. OUTCOME MEASURES: The primary outcome measure was control of suppuration and creation of a dry, low-maintenance mastoid cavity, which was assessed using a previously developed semiquantitative scale. This scale includes a temporal dimension to assess control of infection. Secondary outcome measures included postoperative complications (i.e., hematoma, infection, flap necrosis, and meatal stenosis) and incidence of recurrent or residual cholesteatoma. RESULTS: Forty-nine ears (82%) maintained a small, dry, healthy mastoid cavity. Five ears (8%) had intermittent otorrhea easily controlled by topical treatment. Six ears (10%) had suboptimal control of otorrhea, of which four had meatal stenosis. There were no residual or recurrent cholesteatomas. Outcomes remained stable over progressively longer follow-up, up to 80 months. CONCLUSION: Obliteration of a canal wall down mastoid cavity by a postauricular periosteal-pericranial flap with autologous bone pate is a reliable and effective technique that results in a dry, trouble-free mastoid cavity in 90% of patients with active chronic otitis media.

Adolescent↗
PubMed2005

Aural barotrauma in submarine escape: is mastoid pneumatization of significance?

OBJECTIVE: Submarine escape training is carried out by preselected, healthy young men under strictly controlled conditions regarding exposure to pressure and the rate of pressure change. This provides a unique opportunity to investigate the relations between middle ear characteristics and susceptibility to barotrauma while avoiding possible confounding parameters. We examined a possible association between mastoid pneumatization and middle ear barotrauma (MEB) in submarine escape trainees. STUDY DESIGN: Cross-sectional, parallel-group design. METHODS: Sixty-six subjects aged 19 to 28 participated in the study. The escape simulation included pressurization to 30 or 60 feet followed by a buoyant ascent to the surface. Subjects were evaluated for MEB after each ascent. A Schuller's mastoid radiograph was taken for the evaluation of mastoid pneumatization. RESULTS: Fifteen (23%) of the subjects suffered from MEB, and 6 (40%) of them had bilateral involvement. Repeated impedance audiometry after the completion of a successful ascent revealed a significant increase in middle ear compliance. Schuller's radiographs were obtained from 49 (74%) of the subjects. Of these radiographs, 16 (16%) were of ears that had suffered MEB. Mastoid pneumatization for all ears approached a normal Gaussian distribution, with a mean area of 9.58 cm. The mastoid areas and the proportion of ears with mastoid pneumatization at the extremes of the study population did not differ between barotrauma and no-barotrauma ears. CONCLUSION: In a population with no history of recurrent or chronic otitis media and normal tympanic membrane morphology and compliance, the amount of mastoid pneumatization probably represents merely the normal distribution of variation in organ size and is not related to the ability to equalize pressure in the middle ear.

Acoustic Impedance Tests↗
PubMedDate not supplied

Surgery of the mastoid in ears with middle ear effusion.

It has been demonstrated that in most ears with middle ear effusion the mastoid air cells may be involved as well. The mucosal changes and the secretion extends into all cavities of the ear including the mastoid air cells. In most ears insertin of a ventilating tube through the tympanic membrane is adequate for proper aeration of the middle ear as well as of the mastoid air cell system. The draining usually stops and the mucosa gradually changes into its normal condition. In a small percentage of these, the ear will continue to drain and the mastoid will not clear up. Antibiotics and decongestants fail to cure the ear. Surgical intervention of the mastoid may be indicated in the rare cases where conventional treatment fails to control the condition. The aim of this report is to 1) focus attention to the fact that the mastoid is an integral part of the middle ear cavity; 2) discuss the pathogenesis in stubborn ears with middle ear effusion; and 3) demonstrate the surgical procedure commonly used in our department in order to reestablish aeration of the mastoid air cell system. Early recognition and proper treatment of ears with middle ear effusion will hopefully reduce the incidence of stubborn cases and also decrease the number of those cases which end up with chronic otitis media and cholesteatoma. It is hoped that the screening programs involving school and even preschool children, as well as new preventative programs, will diminish the frequency of cases which need extensive surgery as discussed in this paper.

Ear, Middle↗
PubMedDate not supplied

Subperiosteal mastoid abscesses in chronic suppurative otitis media.

In Europe and America, acute mastoiditis usually appears as a complication of acute otitis media, and some patients develop subperiosteal mastoid abscesses. In Nigeria, however, most subperiosteal mastoid abscesses develop from chronic otitis media with cholesteatoma. Of the 16 patients with subperiosteal mastoid abscesses discussed, 11 (69%) had cholesteatoma and only five (31%) had granulation tissue in the mastoid cavity. The ideal treatment for these cases is modified radical mastoidectomy. Radiographic investigation of the mastoid can be useful in the diagnosis of cholesteatoma in the presence of a subperiosteal mastoid abscess.

Abscess↗
PubMed1994

[Mastoid pneumatization after blocking the aeration route through the eustachian tube].

In the mastoid air cell system, air has been thought to be supplied only through the eustachian tube and tympanic cavity to the cells, and to be absorbed continuously in one direction through the lining mucosa of the mastoid air cells. In the ear with a blocked air supply route to the mastoid air cell system, gas in the blocked mastoid air cells has been thought to be absorbed and to be replaced by exudate. Recently, several observations have supported the existence of gas exchange not only through the eustachian tube but through the lining mucosa in the mastoid. To clarify gas exchange in mastoid air cells, tympanic cavities of the infant piglet, the tympanic bullae of which is similar to the human mastoid air cell system, were filled with jellied adhesive, an alpha-cyanoacrylate monomer, to block the aeration route to the air cells, and tympanic bullae were examined histopathologically. Group 1: Injection of adhesive into the tympanic cavity 1 month after birth following glycerin injection at 1 week after birth. Group 2: Injection of adhesive 1 month after birth without any prior injection into the tympanic cavity. Group 3: Injection of adhesive 3 months after birth without prior injection. In group 1, remarkable inflammation was subsequently observed in the tympanic bullae, development of the air cell system was markedly inhibited and very few air cells remained intact. In groups 2 and 3, however, inflammatory reactions were relatively mild normal air cells remained on the periphery and development of the air cell system was not interrupted.(ABSTRACT TRUNCATED AT 250 WORDS)

Adhesives↗
PubMed2000

Mastoiditis: a disease often overlooked by pediatricians.

Although mastoiditis can be a life threatening disease, clinicians often overlook it because it is uncommon. We reviewed the presentation and management of all children younger than 15 years of age with the discharge diagnosis of mastoiditis in our hospital from January 1994 through December 1999. Nineteen patients that fulfilled the case definition were included. The most common clinical presentation in this series was fever. More specific findings, such as otorrhea, postauricular pain, swelling, and redness of mastoid could be found in less than half of these patients. Only two patients had characteristic physical findings, and mastoiditis was diagnosed in only three patients upon admission. Plain radiographic evidence of mastoiditis was usually not apparent early in the course. In this series, the majority of patients were diagnosed by computed tomography (CT) scans. The present study demonstrates that mastoiditis most commonly presents without a clearly diagnostic set of physical examination and laboratory findings. Mastoiditis should be considered in patients with otitis media or with fever of unknown origin (FUO). The empirical antibiotic treatment should cover organisms commonly found in acute otitis media (AOM), including Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis.

Adolescent↗
PubMed1993

[Masked mastoiditis].

Masked mastoiditis defines a subclinical infectious inflammatory process of the mucosal lining and the bony structure of the mastoid air cells, with intact tympanic membrane. It follows an apparently well-treated recent acute otitis media. Because of obstruction of the tympanic diaphragm by mucosal swelling, polypoid mucosa or granulation tissue, a complete separation of the tubo-tympanic cavity from the mastoid air cell system results. The latter remains unaereated and the local infectious mucosal disease progresses to osteitis. Probably due to colonizing flora in this unventilated media, the developing bone infection is low-grade, without pus formation. The clinical features of the disease are not overt as those in coalescent mastoiditis. The intact ear drum does not reflect the severity of bone-eroding disease within the mastoid. Since this disease is characterized not by exudative but by proliferative changes, there is no pus formation. The incidence of complications is high. Plain x-ray and CT scan do not specifically define the disease process, but bone scan indicates the bone-invading nature of the mastoid infection. The osteoblastic reaction secondary to osteitis is demonstrated by high uptake of the isotope in the involved mastoid. Antibiotics may cure the disease, but in most cases surgery is unavoidable.

Adolescent↗
PubMedDate not supplied

[Influence of secretory otitis media on mastoid pneumatization. Multiple regression analysis].

The influence of secretory otitis media (SOM) on mastoid pneumatization was studied in 122 ears of 61 children under 15 who were seen at our clinic two times. Age, tympanometry, mastoid size, and time between visits were analyzed. Multiple regression analysis yielded and equation relating age and SOM with mastoid size at first examination. Another regression equation explained the contribution of SOM resolution or persistence and age on mastoid size at the time of the second examination. This equation explained 76.14% of the variability in mastoid size and showed that normal ears had better mastoid growth than children with SOM. Even thought inflammation resolved with medical or surgical treatment, mastoid pneumatization was more developed in normal subjects.

Acoustic Impedance Tests↗