Inner-Ear Disorders Presenting with Air-Bone Gaps: A Review

Air-bone gaps (ABGs) are commonly found in patients with conductive or mixed hearing loss generally due to outer- and/or middle-ear diseases such as otitis externa, tympanic membrane perforation, interruption or fixation of the ossicular chain, and chronic suppurative otitis media. ABGs can also be found in correlation with inner-ear disorders, such as endolymphatic hydrops, enlarged vestibular aqueduct syndrome, semicircular canal dehiscence, gusher syndrome, cochlear dehiscence, and Paget disease's as well cerebral vascular anomalies including dural arteriovenous fistula. The typical clinical presentation of inner-ear conditions or cerebral vascular anomalies causing ABGs includes audiological and vestibular symptoms like vertigo, oscillopsia, dizziness, imbalance, spinning sensation, pulsatile or continuous tinnitus, hyperacusis, autophony, auricular fullness, Tullio's phenomenon, and Hennebert's sign. Establishing a definitive diagnosis of the underlying condition in patients presenting with an ABG is often challenging to do and, in many patients, the condition may remain undefined. Results from an accurate clinical, audiological, and vestibular evaluation can be suggestive for the underlying condition; however, radiological assessment by computed tomography and/or magnetic resonance imaging is mandatory to confirm any diagnostic suspicion. In this review, we describe and discuss the most recent updates available regarding the clinical presentation and diagnostic workup of inner-ear conditions that may present together with ABGs.

Influence of middle ear disorder in round-window stimulation using a finite element human ear model

PURPOSE

The aim of this work was to study the effect of middle ear disorder on round window (RW) stimulation, so as to provide references for the optimal design of RW stimulation type middle ear implants (MEIs).

METHODS

A human ear finite-element model was built by reverse engineering technique based on micro-computed tomography scanning images of human temporal bone, and was validated by three sets of comparisons with experimental data. Then, based on this model, typical disorders in otosclerosis and otitis media were simulated. Finally, their influences on the RW stimulation were analyzed by comparison of the displacements of the basilar membrane.

RESULTS

For the otosclerosis, the stapedial abnormal bone growth severely deteriorated the equivalent sound pressure of the RW stimulation at higher frequencies, while the hardening of ligaments and tendons prominently decreased the RW stimulation at lower frequencies. Besides, among the hardening of the studied tissues, the influence of the stapedial annular ligament's hardening was much more significant. For the otitis media, the round window membrane (RWM)'s thickening mainly decreased the RW stimulation's performance at lower frequencies. When the elastic modulus' reduction of the RWM was considered at the same time especially for the acute otitis media, it would raise the lower-frequency performance of the RW stimulation.

CONCLUSIONS

The influence of the middle ear disorder on the RW stimulation is considerable and variable, it should be considered during the design of the RW stimulation type MEIs.

High-frequency conductive hearing loss as a diagnostic test for incomplete ossicular discontinuity in non-cholesteatomatous chronic suppurative otitis media

Chronic suppurative otitis media, with or without cholesteatoma, may lead to erosion of the ossicles and discontinuity of the ossicular chain. In incomplete ossicular discontinuity (IOD), partial erosion of the ossicles occurs, but some sound transmission is noted throughout the ossicular chain. High-frequency conductive hearing loss (HfCHL) has been considered a hallmark of incomplete ossicular discontinuity. This study aims to evaluate the use of HfCHL as a preoperative predictor of IOD in patients with non-cholesteatomatous chronic suppurative otitis media. The HfCHL test was defined as the preoperative air-bone gap (ABG) at 4 kHz minus the average of the ABG at 0.25 and 0.5 kHz. The test was applied in 328 patients before surgery and compared to intraoperative findings as the gold standard. At surgery, 201 (61.3%) patients had an intact ossicular chain, 44 (13.4%) had a complete ossicular discontinuity, and 83 (25.3%) exhibited an IOD. The best cutoff level was calculated as 10 dB. The HfCHL test to diagnose IOD had a sensitivity of 83% and a specificity of 92% with a post-test probability of 78% and a likelihood ratio of 10.2. We concluded that the HfCHL test is highly effective in predicting IOD in patients with non-cholesteatomatous chronic suppurative otitis media and that it should be used routinely as a screening test prior to surgery.

[The prevalence of tympanosclerosis and the effectiveness of its surgical treatment]

The objective of the present study was to characterize the epidemiological variants of tympanosclerosis and the effectiveness of the surgical treatment of the patients presenting with this condition. We have undertaken the analysis of the results of 1965 surgical interventions on the patients suffering from different forms of chronic otitis media (COM) performed during the period from 2009 till 2014 with a view to determining the frequency of tympanosclerosis (TSC). In 542 cases, it proved possible to evaluate the intraoperative findings, stages and methods of reconstructive surgery, the anatomical and functional outcomes and effectiveness of the intervention. At present, the signs of tympanosclerosis are identified in 27.6% of the patients presenting with chronic otitis media including 88.7% and 11.3% suffering from the perforating and non-perforating forms of this pathology, respectively. In 74% of the cases its manifestations are diagnosed in the patients having the tubotympanic form of COM. In 53.3% of the patients TSC foci are responsible for the fixation of the ossicular chain whereas in 46.7% of the cases the auditory ossicles retain mobility. As many as 88.6% of the patients underwent the one-step surgical intervention, 10.7% were managed using two-step surgery, and 0.7% of the patients were given the three-stage treatment. Type I tympanoplasty was performed in 62% of the patients, type III tympanoplasty in 30.4%, and various types of stapedoplasty in 4.6% of the cases. The favourable anatomical and functional outcomes at the first stage of the surgical intervention with the use of the autogenous tissues for tympano- and ossiculoplastic surgery were achieved in 87.9% of the patients on the average (by means of the closure of the tympanic defect in 92.2% and by re-fixation of the selected elements of the ossicular chain in 17.3%of the cases). The anatomical and functional effectiveness of the second-stage surgical intervention was estimated at 93.1%.

Ossicular Bone Damage and Hearing Loss in Rheumatoid Arthritis: A Correlated Functional and High Resolution Morphometric Study in Collagen-Induced Arthritic Mice

Globally, a body of comparative case-control studies suggests that rheumatoid arthritis (RA) patients are more prone to developing hearing loss (HL). However, experimental evidence that supports this hypothesis is still lacking because the human auditory organ is not readily accessible. The aim of this study was to determine the association between bone damage to the ossicles of the middle ear and HL, using a widely accepted murine model of collagen-induced arthritis (RA mice). Diarthrodial joints in the middle ear were examined with microcomputer tomography (microCT), and hearing function was assessed by auditory brainstem response (ABR). RA mice exhibited significantly decreased hearing sensitivity compared to age-matched controls. Additionally, a significant narrowing of the incudostapedial joint space and an increase in the porosity of the stapes were observed. The absolute latencies of all ABR waves were prolonged, but mean interpeak latencies were not statistically different. The observed bone defects in the middle ear that were accompanied by changes in ABR responses were consistent with conductive HL. This combination suggests that conductive impairment is at least part of the etiology of RA-induced HL in a murine model. Whether the inner ear sustains bone erosion or other pathology, and whether the cochlear nerve sustains pathology await subsequent studies. Considering the fact that certain anti-inflammatories are ototoxic in high doses, monitoring RA patients’ auditory function is advisable as part of the effort to ensure their well-being.

Bony ankylosis of hydroxyapatite prostheses in the middle ear

BACKGROUND

Ossiculoplasty is a commonly performed middle ear procedure. Ossicular chain reconstruction (OCR) prostheses should be made of a biocompatible material; one such common material is hydroxyapatite (HA).

METHODS

2 patients were identified who had HA OCR prostheses which had fused to the middle ear bony structures. One HA OCR had fused to the fallopian canal in the tympanic segment and represented a management dilemma. The other fused to the scutum.

CONCLUSION

Bony ankylosis of a HA containing OCR prosthesis should be considered in the differential diagnosis of a failed ossiculoplasty. Depending on the location of the fusion, special measures may be needed to free the prosthesis from the underlying middle ear structures.

Autograft ossiculoplasty in cholesteatoma surgery: a histological study

CONCLUSION

The results of the present study reject the hypothesis that epithelial inclusions into the ossicles could cause cholesteatoma recurrences, but strongly suggest the performance of a safe cleaning procedure for ossicular remnants to make them usable in ossiculoplasty in patients with partially or non-encapsulated cholesteatoma.

OBJECTIVE

The aim of the study was to define, before any sort of cleaning procedure, if there is any epithelial inclusion inside the ossicles of patients with cholesteatoma and if the findings could be correlated with surgical aspect of cholesteatoma.

METHODS

The specimens used for this study comprised 19 mallei and 15 incudes, which were obtained intraoperatively from 24 patients. Each ossicle was grouped on the basis of the intraoperative aspect of the cholesteatoma as follows. Grade 1: 10 ossicles obtained from encapsulated cholestatoma, non-invasive, easily cleavable. Grade 2: 14 ossicles obtained from partially encapsulated cholesteatoma, non-invasive, not easily cleavable. Grade 3: 10 ossicles obtained from non-encapsulated cholesteatoma, invasive, not cleavable. Two stapes and one malleus were taken from patients who underwent middle ear surgery for conductive hearing loss and were used as controls. The ossicles were examined histopathologically after removal.

RESULTS

Our results do not show any epithelial inclusion inside the ossicles independently from the macroscopic aspect or growing aggressiveness of cholesteatoma. In addition there was no infiltration of inflammatory cells in grade 1, but it was present in one incus (7.1%) of grade 2 and in five ossicles (50%) of grade 3. In ossicles of grade 3 up to four layers of epithelial cells were found on the surface of the ossicles.

Analysis of differences in facial nerve dehiscence and ossicular injury in chronic otitis media and cholesteatoma

CONCLUSION

Facial nerve dehiscence (FND) and ossicular injury occurred more frequently in patients with cholesteatomatous than non-cholesteatomatous otitis media.

OBJECTIVE

FND and ossicular injury commonly occur intraoperatively in patients with otitis media, both with and without cholesteatoma. This study was designed to analyze differences in FND and ossicular injury between patients with cholesteatomatous and non-cholesteatomatous otitis media.

METHODS

Patients who underwent tympanomastoidectomy due to otitis media from January 2010 to July 2012 were analyzed retrospectively. Clinical features (age, sex, bacteria, and severity of preoperative hearing loss) and intraoperative findings (FND and state of ossicular injury) were compared in patients with cholesteatomatous and non-cholesteatomatous otitis media.

RESULTS

Of 212 patients with otitis media, 148 (69.8%) had non-cholesteatomatous and 64 (30.2%) had cholesteatomatous otitis media. Of these groups, 88.6% and 88%, respectively, had positive bacterial cultures. Facial nerve dehiscence was detected in 41 patients (27.7%) with non-cholesteatomatous and 41 (64.0%) with cholesteatomatous otitis media. Dehiscence of the tympanic segment was most frequently observed in both groups. Ossicular injury was detected in 52 (35.1%) and 51 patients (78.1%), respectively. Erosion was most frequent in the incus, followed by the stapes and malleus.

Endoscopic findings of the external ear canal in a group of clinically normal horses and horses with head shaking or vestibular disease

Since there is a lack of information about the normal appearance or pathological findings of the equine external ear canal (EEEC) and tympanic membrane (TM), we aimed to find a practical way to perform the otoscopic examination in standing, sedated horses. Therefore, we worked with common veterinary video endoscopes, which are normally used for gastroscopy or bronchoscopy. Both ears each of 38 randomly selected, chemically restrained horses were otoscopically examined. 33 of those horses had no history or signs of potentially ear-associated diseases. However, two horses with vestibular disease and three horses with head shaking were included in the otoscopic examinations. We created references of the normal appearance of the EEEC and TM on the basis of the characteristic anatomical landmarks, degree of debris, amount of keratin scales, shape of the intersection between the cartilaginous (CEEC) and osseous (OEEC) portion of the external ear canal, shape of the OEEC, formation of the keratin layer and its integrity, epithelium colour of the OEEC, and complexion of the TM. With this information, we were able to visualise tympanosclerosis in two equine eardrums, as well as low-grade to severe external otitis in three horses. Severe bilateral external otitis combined with temporohyoid osteoarthropathy (THO) was found in one of those horses. A foreign body was found in one OEEC. This study shows that otoscopic examination is a basic, easy to perform and beneficial diagnostic procedure for a complete work-up of ear-related diseases, such as THO, facial nerve paralysis, vestibular disease, head-shaking or head trauma. Plus, regarding animal welfare, well being of horses is highly influenced by noise exposure. Therefore research on equine audiological aspects needs to be promoted. The standardized otoscopic examination provides an important basis for further research on aural diseases.

Activation of the IL-6/JAK/STAT3 signaling pathway in human middle ear cholesteatoma epithelium

Interleukin-6 (IL-6) is one of the most important cytokines which has been shown to play a critical role in the pathogenesis of cholesteatoma. In this study, we aimed to investigate the expression of interleukin-6 (IL-6) and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in middle ear cholesteatoma epithelium in an effort to determine the role of IL-6/JAK/STAT3 signaling pathway in the pathogenesis of cholesteatoma. Immunohistochemistry was used to examine the expression of IL-6 and p-STAT3 in 25 human middle ear cholesteatoma samples and 15 normal external auditory canal (EAC) epithelium specimens. We also analyzed the relation of IL-6 and p-STAT3 expression levels to the degree of bone destruction in cholesteatoma. We found that the expression of IL-6 and p-STAT3 were significantly higher in cholesteatoma epithelium than in normal EAC epithelium (p<0.05). In cholesteatoma epithelium, a significant positive association was observed between IL-6 and p-STAT3 expression (p<0.05). However, no significant relationships were observed between the degree of bone destruction and the levels of IL-6 and p-STAT3 expression (p>0.05). To conclude, our results support the concept that IL-6/JAK/STAT3 signaling pathway is active and may play an important role in the mechanisms of epithelial hyper-proliferation responsible for cholesteatoma.

[Acquired pediatric cholesteatoma: predictive factors of recurrence. A retrospective study of 11 years]

AIM OF THE STUDY

To define the predictive factors of recurrence of the pediatric acquired cholesteatoma in order to improve the long-term results, to restore a good hearing function and to prevent the complications.

PATIENTS AND METHODS

A retrospective study concerning all cases of pediatric acquired cholesteatoma, treated during the period 1997-2008 in our center, and followed up for at least one year. A description of the parameters concerning the patients, disease and treatment as well as a univariate analysis were undertaken in order to determine the recurrence predictors. The recurrence-free survival was calculated using the Kaplan-Meier method.

RESULTS

26 ears were studied and followed over a mean period of 62 months after the first intervention. The mean age was 12 years (11.7 years) with a 2.7 sex-ratio. The main clinical presentations were otorrhea (65%) and hypoacusia in 42% of cases. Fifteen cases (57.7%) presented an extension to the mastoid, 50% of the ears had an ossicular erosion and 11 cholesteatomas revealed a local or regional invasion. Almost 3/4 (73%) of the cholesteatomas were treated using a canal wall up surgery. The cumulative rate of recurrence was 53.8% and the rate of recurrence-free survival was 84%, 56%, and 44.7% at 12, 24 and 36 months respectively. Only the extension of the cholesteatoma to the mastoid, and the local and regional invasion (sinus tympani, lateral semi-circular canal, facial nerve recess, etc.) of the cholesteatoma at diagnosis, showed a significant higher risk of recurrence (p < 0.05).

CONCLUSION

In our study, the extent of the disease at diagnosis is considered as the major predictive factor of recurrence in pediatric acquired cholesteatoma population raising the problem of delayed diagnosis.

Transtympanic endoscopy for diagnosis of middle ear pathology

Office-based transtympanic endoscopy through the perforation made by laser-assisted myringotomy (LAM) has been introduced for diagnosis of ossicular interruption, stapes fixation, tympanosclerosis, congenital cholesteatoma, and perilymphatic fistula. Endoscopy of the middle ear reveals minor anomalies around the incudostapedial joint and the superstructure of the stapes. This procedure can be also applied to diagnose stapes fixation and perilymphatic fistula not diagnosed presurgically, and requires exploratory tympanotomy to make a definite diagnosis. Transtympanic endoscopy using LAM is a direct and reliable preoperative diagnostic method for abnormalities of the middle ear, offers better surgical indications and patient consultation, and is a potential alternative to exploratory tympanotomy.

[Destrution of ossicular chain and it's impact on hearing of patients with tympanosclerosis]

OBJECTIVE

To study the destruction ossicular chain's impact on hearing of patients with tympanosclerosis.

METHOD

A retrospective review was conducted in 115 patients with tympanosclerosis, all patients were divided into 3 groups, including normal ossicular chain structure (A group), fixed ossicular chain(B group), and interrupted ossicular chain (C group). The audiological feature of the patients were compared between the 3 group.

RESULT

Difference were significant for PTA, 0.5, 1.0, 2.0, 4.0 kHz air conduction threshold between 3 group (P < 0.01). Difference were significant for air bone gap (ABG) between A, B groups and C group (P < 0.01), there was no difference for ABG between A and B group (P > 0.01). Difference were significant for air conduction threshold between 0.5, 1.0 kHz and 2, 4 kHz in A, B groups (P < 0.01), but there was no significant for same data in C group (P > 0.01). Difference were significant for average bone conduction, 1, 2, 4 kHz bone-conduction threshold between A group and B, C group (P < 0.01). The rate of Carhart notch was low and had no difference between 3 group (P > 0.01).

CONCLUSION

The ossicular chain was fixed in patients who's PTA > or = (54.31 +/-13.19) dB HL and was interrupted who's PTA > or = (63.90 +/- 20.29) dB HL or ABG > or = (33.23 +/- 8.49) dB HL. The rising shaped curve in air-conduction audiograph may indicate the ossicular chain was fixed,and the smooth shape curve may indicate the ossicular chain was interrupted.

On the biology of the bony otic capsule and the pathogenesis of otosclerosis

In human otosclerosis, focal pathological bone remodeling occurs in significant amounts inside the normally anti-resorptive perilabyrinthine domain of the bony otic capsule. Otosclerosis causes hearing loss in 0.2-0.5% of the population by ankylosis of the footplate. The disease cannot be predicted, avoided or medically reversed as the pathogenesis remains unknown. Previously genetic research has failed to identify a specific otosclerosis-gene and earlier theories of virus infections, autoimmunity or association to generalized bone diseases have been unable to explain why otosclerosis only occurs in the bony otic capsule while the rest of the skeleton remains completely normal. Studies from the otopathological laboratory (RH) have revealed how the bone turnover rates increase centrifugally from a sub-normal 0.1% adjacent to the inner ear space towards a normal 10% per year at the capsular periphery. This graded restriction of bone remodeling is most likely caused by the anti-resorptive action of the cytokine osteoprotegerin (OPG), which is expressed in high levels (1000 x normal bone levels) by inner ear structures to inhibit perilabyrinthine osteoclast formation and function. OPG knockout mice develop excessive, irregular bone remodeling, stapes fixation and progressive hearing loss. The lacuno-canalicular porosity is the candidate anatomical routes for the transmission of OPG-derived signals to the surrounding bone. This extracellular signaling pathway depends crucially on the viability of individual osteocytes. When bone remodeling is low, the average age of the bone matrix and osteocytes increases. We detected a high fetal density of labyrinthine osteocytes, which may secure a life-long anatomical route for inner ear OPG despite accumulation of non-viable osteocytes. Moreover, 3-D reconstructions and vector-based stereology revealed a co-existence between non-viable osteocytes and otosclerosis. We suggest that bone remodeling may commence when the effect of anti-resorptive OPG fails locally within regions of non-viable osteocytes. A sustained OPG signal from surrounding osteocyte survivors might distort the process and account for the otosclerotic morphology.

Effects of high hydrostatic pressure on bacterial growth on human ossicles explanted from cholesteatoma patients

BACKGROUND

High hydrostatic pressure (HHP) treatment can eliminate cholesteatoma cells from explanted human ossicles prior to re-insertion. We analyzed the effects of HHP treatment on the microbial flora on ossicles and on the planktonic and biofilm states of selected isolates.

METHODOLOGY

Twenty-six ossicles were explanted from cholesteatoma patients. Five ossicles were directly analyzed for microbial growth without further treatment. Fifteen ossicles were cut into two pieces. One piece was exposed to HHP of 350 MPa for 10 minutes. Both the treated and untreated (control) pieces were then assessed semi-quantitatively. Three ossicles were cut into two pieces and exposed to identical pressure conditions with or without the addition of one of two different combinations of antibiotics to the medium. Differential effects of 10-minute in vitro exposure of planktonic and biofilm bacteria to pressures of 100 MPa, 250 MPa, 400 MPa and 540 MPa in isotonic and hypotonic media were analyzed using two patient isolates of Staphylococcus epidermidis and Neisseria subflava. Bacterial cell inactivation and biofilm destruction were assessed by colony counting and electron microscopy.

PRINCIPAL FINDINGS

A variety of microorganisms were isolated from the ossicles. Irrespective of the medium, HHP treatment at 350 MPa for 10 minutes led to satisfying but incomplete inactivation especially of gram-negative bacteria. The addition of antibiotics increased the efficacy of elimination. A comparison of HHP treatment of planktonic and biofilm cells showed that the effects of HPP were reduced by about one decadic logarithmic unit when HPP was applied to biofilms. High hydrostatic pressure conditions that are suitable to inactivate cholesteatoma cells fail to completely sterilize ossicles even if antibiotics are added. As a result of the reduced microbial load and the viability loss of surviving bacteria, however, there is a lower risk of re-infection after re-insertion.

[Clinical analysis of 118 patients with tympanosclerosis]

OBJECTIVE

To study the incidence of tympanosclerosis (TS) and the major risk factors of hearing loss.

METHODS

A total of 118 TS patients (137 ears) were compared with 265 patients with chronic otitis media (COM) (311 ears) for gender, age and course of disease. The disease regions and hearing loss of the TS patients were analyzed.

RESULTS

TS showed higher prevalence in women of older ages. Sclerosis was seen most frequently in the tympanic membrane, followed by the malleus, incus, incudomalleolar joint, other regions, ariticulus incudostapedius and stapes. The patients with sclerosis or deterioration in the ossicular chain had worse hearing loss than the other patients. Carhart notch occurred in 45 ears (32.85%), an incidence similar to that of inverted "V"-shaped curve of air-conduction audiometry near 2 kHz (47 ears, 34.31%). The factors contributing to the hearing loss, listed in the order of their importance, included pathologies in the incus, malleus, incudomalleolar joint, ariticulus incudostapedius, stapes, other regions, tympanic membrane, and gender.

CONCLUSIONS

Female patients may had increased risk of TS. The presence of Carhart notch and inverted "V"-shaped curve in air-conduction audiograph may indicate myringosclerosis or ossicular chain sclerosis. Abnormal ossicular chain is the leading factor contributing to hearing loss.

The functional and anatomical results of the canal wall down tympanoplasty in extensive cholesteatoma

CONCLUSION

Although we have shown that malleus handle and mucosal factors were important prognostic factors for hearing, we were unable to show the positive effect of the stapes superstructure on hearing results. The positive effect of the presence of the stapes superstructure on hearing results is closely related to the quality of the mucosa.

OBJECTIVE

The aim of this study was to investigate the impact of ossicular and mucosal factors on hearing in primary canal wall down (CWD) surgery with ossicular chain reconstruction (OCR) performed for extensive acquired cholesteatoma.

PATIENTS AND METHODS

A total of 134 adults who had CWD surgery with OCR for extensive acquired cholesteatoma between January 1996 and May 2007 were retrospectively analyzed.

RESULTS

The graft insufficiency was 13%, chronic infection without cholesteatoma was 6% and cholesteatoma recurrence was 8% after the first operations. The rate of anatomic failure was 10% after a follow-up period of 46.3 months. In this study, we present the anatomic results for 136 ears and functional results for 135 ears. The hearing gain was significantly higher in the cholesteatoma-only group when compared with the mucosal-cholesteatoma disease group. Forty-three ears (54%) in the cholesteatoma-only group and 23 ears (42%) in the mucosal-cholesteatoma disease group had postoperative ABG within 20 dB. The best hearing results were obtained in Austin group B, while the worst hearing results were evident in Austin group C (p=0.017). Postoperative ABG was within 20 dB in 44% (n=31) of the patients with an intact stapes superstructure, while this ratio was 54% (n=35) when the stapes superstructure was absent.

The imbalance of enzymatic antioxidants in cholesteatoma

CONCLUSION

Depletion of enzymatic antioxidants was observed in cholesteatoma. However, a relationship between activity of enzymatic antioxidants and the extent of bone erosion was not found.

OBJECTIVES

To measure the level of major enzymatic antioxidants in cholesteatoma, and to investigate the relationship between the level of enzymatic antioxidants and the extent of bone erosion.

PATIENTS AND METHODS

The cholesteatoma and skin samples were obtained during otologic surgeries. All cases were grouped according to the number of bone erosion sites. Samples were examined biochemically and the levels of enzymatic antioxidants were measured. The results were analyzed statistically.

RESULTS

Thirteen patients were included in the study. The mean level of superoxide dismutase in cholesteatoma and skin was 45.87 U/mg and 71.04 U/mg, respectively. When the catalase level was evaluated, the mean level was 5.04 U/g in cholesteatoma and 11.62 U/g in skin. The mean level of glutathione peroxidase in cholesteatoma and skin was 12.13 IU/g and 236.74 IU/g, respectively. All the results of cholesteatoma and skin samples were compared through non-parametric tests and statistically significant differences were found. However, a statistically significant difference between the levels of enzymatic antioxidants and the extent of bone erosion was not observed.

Changes in auditory ossicles in rheumatoid arthritis: scanning electron microscopic study

The aim of this study was to define the existence of surface changes on auditory ossicles caused by rheumatoid arthritis. The study comprised of nine pairs of auditory ossicles (mallei and incudes) from autopsy of patients with rheumatoid arthritis, and five pairs of ossicles from persons without RA, taken during autopsies. The specimens were studied with JEOL JSM 5300 type scanning electron microscope. Surface changes of auditory ossicles were defined, affected areas were calculated, and expressed in percentage of total surface. Changes in auditory ossicles in patients with rheumatoid arthritis are significantly higher than in control ossicles, both on ossicular surface and articulations. Increased lysis of incudes, especially in the region of long propagation, corresponds to vascular damage. Articular degeneration is also present, indicating specific rheumatoid alteration. Both changes are statistically more intense in cases with longer duration of disease. In conclusion, rheumatoid arthritis reduces vascularity of auditory ossicles and causes degeneration of articular surfaces.

[Os odontoideum: clinical and radiological aspects]

Few reports of os odontoideum have been made. We report two cases where this affection was revealed by cervical pain and hemiparesis in one case and acute tetraparesis in the other. Patients with os odontoideum usually present with neurological signs, but some have only cervical pain and some others remain asymptomatic. Radiological exams, including radiograms, cervical scanner and MRI lead to the diagnosis. Different surgical treatment can be proposed to symptomatic patients. Prophylactic surgical treatment is not indicated.

Bilateral duplication of the internal auditory canal

Duplication of the internal auditory canal is an extremely rare temporal bone anomaly that is believed to result from aplasia or hypoplasia of the vestibulocochlear nerve. We report bilateral duplication of the internal auditory canal in a 28-month-old boy with developmental delay and sensorineural hearing loss.

Outer- and middle-ear contributions to presbycusis in the Brown Norway rat

This paper examines the contribution of the outer and middle ears to the hearing loss associated with presbycusis in Brown Norway rats. Animals were formed into two groups; young adults (2-3 months old) and aged animals (approximately 34 months old). Auditory brainstem response (ABR) thresholds were obtained with the outer ear intact or surgically removed. Tympanic membrane (TM) velocity transfer functions were measured from the umbo with the outer ear removed. The length of the auditory meatus, TM surface area, and TM thickness were quantified. The ABR thresholds were 17-26 dB less sensitive in the aged animals between 8.0 and 40.0 kHz when the outer ear was intact. A significant and reliable reduction in the aged rat velocity transfer function of 5-8 dB occurred between 10.0 and 32.0 kHz, while the low frequency velocity response was only a few decibels greater in the younger animals. The ABR threshold differences between young adult and aged ears were compensated by removing the outer/middle ear effects of aging to reveal a purely sensorineural component of presbycusis. The outer and middle ear effects were calculated directly when the ABR and TM velocity data were obtained with the outer ear removed. The outer ear intact condition was modeled in order to compare the ABR data obtained with the outer ear intact with the TM velocity data obtained with the outer removed. With either procedure, removal of the age-related contributions of the outer and middle ear to the ABR threshold resulted in similar age-related ABR threshold shifts between the two age groups. The pure sensorineural threshold shift component of the ABR response was restricted to frequencies between 5.0 and 20.0 kHz and reached a maximum of approximately 15 dB. These results support the conclusion that there is an outer- and middle-ear contribution to the threshold loss defining presbycusis.

[Auditory brainstem response (ABR) during stapes mobilization under general anaesthesia in children]

The Authors executed checking a result of stapes mobilization under anesthesia in children, sick otosclerosis. The Study ABR was conducted before operations, after opening the drum cavity, making the hole in plate of stapes, installing the prosthetic device and at the end of operation. The reduction level of latency V wave and interval III-V and I-V waves are a reliable acknowledgement of the improvement of the hearing at the end of operation.

[Post-traumatic cholesteatoma of temporal bone]

Posttraumatic cholesteatoma of the middle ear is a rare condition that may present years after temporal bone fracture. We present the 36 years old woman with acquired cholesteatoma of the middle ear and perilymphatic fistula six years after a temporal bone fracture. CT scan was extremely helpful in determining the sites of fracture and fasioning the surgical approach. The middle ear was cleaned with cholesteatoma, perilymphatic fistula was sealed with 3 layers of tissues and the ossicular chain was reconstructed in one stage. The presence of fracture lines in temporal bone years after trauma may prove hindered healing, which promotes migration of epithelium from external ear canal into the middle ear. We recomend long term follow-up in any patient with longitudinal temporal bone fracture with CT for any new otologic complaints.

The Erasmus atelectasis classification: proposal of a new classification for atelectasis of the middle ear in children

OBJECTIVES

Atelectasis presents a challenging, often progressive, problem in children. Because of the lack of a clinically practical classification, we introduce a new classification, which in our opinion is more useful in the pediatric age group. This alternative classification enables a more clinically relevant correlation between stage of disease and clinical sequelae and technical difficulty at surgery.

STUDY DESIGN

Observational study of patients seen and operated at the Sophia Children's Hospital in Rotterdam, The Netherlands between 1989 and 2005.

METHODS

Based on clinical appearance, each ear was placed into one of the five groups of the proposed classification and into one of the four stages of Sadé's classification. Preoperative air and bone conduction thresholds and air-bone gaps (ABG) were calculated using the four-tone pure-tone (500, 1,000, 2,000, and 4,000 Hz) averages for bone and air conduction.

RESULTS

: Of the 248 ears in the study group, 72 were in stage I, with an ABG of 18.2 +/- 12.3 dB. Twenty-two were in stage II, with an ABG of 12.9 +/- 9.5 dB. In stage III, there were 32 ears, with an ABG of 11.6 +/- 10.0 dB. Thirty-one ears were in stage IV, with an ABG of 16.1 +/- 11.5 dB. Eighty-five ears were in stage V, with an ABG of 26.1 +/- 13.3 dB. When grouped according to Sadé's classification, 92 ears could not be classified.

CONCLUSIONS

We found the currently proposed classification more useful in that it follows the natural progression of the disease and is more practical in determining operative procedures at each stage.

Evolution of Middle Ear Changes After Permanent Eustachian Tube Blockage

OBJECTIVE

To develop a valid animal model for otitis media with effusion (OME).

DESIGN

Forty specific pathogen-free Wistar rats underwent a procedure based on the permanent obstruction of pharyngeal eustachian tube by means of electrocoagulation without any manipulation.

SETTING

Ear Research Group, Department of Otorhinolaryngology, Puerta de Hierro Hospital, Universidad Autonoma de Madrid, Madrid, Spain.

MAIN OUTCOME MEASURES

The assessment of OME by otoscopy and tympanometry. The rats were humanely killed at 15 and 90 days, and temporal bones were obtained and processed for histopathologic study.

RESULTS

The histopathologic study of the temporal bones demonstrated the occurrence of chronic effusion and mucosal changes owing to mucoperiosteal enlargement.

CONCLUSIONS

Comparison with other experimental models was made. Our animal model was consistent and reproducible and resembled human OME.

Histopathology of ossicular grafts and implants in chronic otitis media

OBJECTIVES

We describe the histopathology of ossicular grafts and implants so as to provide insight into factors that may influence functional results after surgery for chronic otitis media.

METHODS

Histopathologic observations were made on 56 cases: 50 surgical specimens and 6 temporal bone cases in which the graft was sectioned in situ.

RESULTS AND CONCLUSIONS

Autogenous malleus, incus, and cortical bone grafts behaved in a similar manner and maintained their morphological size, shape, and contour for extended periods of time, at least up to 30 years. These histopathologic observations support the continued use of autograft ossicular and cortical bone grafts for middle ear reconstruction. Cartilage grafts developed chondromalacia with resulting loss of stiffness and showed a tendency to undergo resorption. Synthetic prostheses made of porous plastic (Plastipore, Polycel) elicited foreign body giant cell reactions with various degrees of biodegradation of the implants. Prostheses made of hydroxyapatite and Bioglass were enveloped by a lining of connective tissue and mucosal epithelium. The Bioglass material was broken down into small fragments and partially resorbed by a host response within the middle ear. These results warrant caution in the use of prostheses made of porous plastic or Bioglass.

Measles virus prevalence in otosclerotic foci

The etiology of otosclerosis is still unknown. Persistent measles virus infection of the otic capsule is supposed to be one of the etiologic factors in otosclerosis. The presence of measles virus was shown in otosclerotic patients by RT-PCR amplification of the viral RNA, detecting the viral proteins by immunohistochemistry and antimeasles immunoglobulin G in the perilymph samples. Nucleic acid (mRNA, vRNA, DNA) was extracted from pulverized, frozen stapes footplate samples of otosclerotic patients. Measles virus RNA was amplified by RT-PCR: reverse transcription and the first-round PCR amplification were performed by heat-stable recombinant Thermus thermophilus polymerase, while in the nested round PCR Taq polymerase was employed. Oligonucleotide primers specific to measles virus nucleoprotein and matrix protein RNA were used in these reactions. Edmonston- and Schwartze-type measles viruses served as positive controls and cortical bone fragments, stapes superstructures, cadaver stapes, incus and malleolar samples served as negative controls. Among 102 otosclerotic patients, 62 stapes footplate samples contained measles virus RNA. Measles virus RNA was not detected in other bone specimens of the patients. The etiologic role of measles virus in the pathogenesis of otosclerosis should be considered. The 40 negative samples may be genetically determined otosclerotic cases or stapes fixations due to other causes.

Applicability of autologous incus: the influence of age and localization of cholesteatoma

There is a correlation between macroscopic and histologic changes of incus in chronic otitis with cholesteatoma. The incidence and types of damage of auditory ossicles in chronic otitis media were extensively studied, but except some studies on reoperations there are no morphometric studies of human auditory ossicles in chronic otitis media. In order to define the rate of ossicular applicability for tympanoplasties in different macroscopic forms of damage, we analysed histologic changes of human incudes in correlation to their macroscopic alterations. Histomorphometric study of 82 intraoperatively removed human incudes, from chronic otitis media with cholesteatoma (attic, sinus, tensa cholesteatoma), was performed. They were divided according to the age of patients and localization of cholesteatoma. Erosions, vitality, vascular areas, osteomyelitic zones, and applicability of ossicles were measured. Progressive increase of erosions, decrease of vitality, dilatation of vascular spaces and osteomyelitic areas, and decrease of rate of potential applicability for tympanoplasties were found. Residual osteomyelitis was present in incudes with advanced external osteitis and ossicular defect. Macroscopic changes of incudes in cholesteatoma and their histologic structure correlate. Localisation of cholesteatoma is important for ossicular damage. Defects of long process with external osteitis of incudes and more intense pathological changes demand their removal and use of other reconstructive materials for tympanoplasties in order to avoid tympanoplasty failure.

[Expression and significance of nuclear factor-kappa B ligand and correlation factor in the tissue of otitis media with cholesteatoma]

OBJECTIVE

To investigate the expressions of nuclear factor-kappa B ligand (RANKL), receptor activator of nuclear factor-kappa B(RANK)and osteoprotegerin (OPG) and the relation of RANKL with bone- erosion in human cholesteatoma tissue.

METHOD

Thirty cholesteatoma and twenty normal auditory canal skin specimens were investigated. The expressions of RANKL, RANK and OPG were examined by immunohistochemistry.

RESULT

The overexpressions of the cytokine RANKL and RANK were found in infiltrated lymphocytes in the cholesteatoma tissue comparing with normal external meatal skin( t = 7. 758,6. 482, P <0. 05); While, the expression of OPG was significantly higher in cholesteatoma tissue comparing with normal external meatal skin. the OPG/ RANKL was decreased in cholesteatoma tissue comparing with normal external meatal skin( t = 8. 183, P < 0. 05).

CONCLUSION

This study revealed that the expressions level of RANKL and RANK were markedly increased in the perimatrix of cholesteatoma, which is closely related to the bone- erosion induced by cholesteatoma.

[The morphological study of eroded auditory ossicles by cholesteatoma]

OBJECTIVE

To observe the morphology of eroded auditory ossicles obtained in middle ear surgery for cholesteatoma and to investigate the mechanism of bone erosion in cholesteatoma.

METHOD

The morphology of eroded auditory ossicles in 8 cholesteatoma cases and 2 normal cases were observed with light microscopy. The ultrastructure of eroded auditory ossicles in 5 cholesteatoma cases and the ultrastructure of control bones in external ear canal of 2 cases were observed and compared with transmission electron microscopy.

RESULT

Osteomyelitis and multinucleate osteoclasts with ruffled borders were observed in the eroded auditory ossicles of cholesteatoma. Intramembranous and endochondral ossification were both observed. The obvious bone destruction and remodeling were observed consistently.

CONCLUSION

Osteoclasts and Osteomyelitis are both responsible for bone destruction in cholesteatoma. Intramembranous and endochondral ossification may co-participate in bone remodeling. Osteogenesis is also a basic pathologic phenomena in cholesteatoma. The obvious bone destruction and remodeling can coexist in cholesteatoma cases.

Ossicular necrosis following head injury

PROBLEMS/OBJECTIVES

The aim of this study is to report on ossicular necrosis in the middle ear occurring shortly after head injury.

METHODOLOGY

Our sample included 3 males and 2 females aged 9 to 37 years who complained of unilateral hearing loss after a head trauma that had occurred 3 to 6 months previously. The tympanic membranes were intact, and a CT-scan did not show fracture of the temporal bone. Audiometry showed a unilateral conductive hearing loss in all cases.

RESULTS

On tympanotomy exploration, 4 of the 5 patients had a necrosis of the lenticular process of the incus and one patient had a necrosis of the posterior and anterior crura of the stapes. Additionally, the incus was displaced at the incudomalleolar joint towards the promontory in two patients. The long process of the incus was surgically aligned and adjusted to the head of the stapes through interposition of either temporal fascia or a bone chip. At the 2-year-postoperative follow-up, the pure tone audiometry showed that the preoperative air-bone gap was almost closed with a mean of 11.8 dB.

CONCLUSIONS

It is possible that the head injury resulted in ossicular displacement in the middle ear with disturbance of the local vascular supply. Due to the tenuous blood supply to the lenticular and long processes of the incus, this portion of the ossicular chain, including the stapes suprastructure, may become more vulnerable to an ischemic process and subsequent necrosis shortly after the head trauma.

Tympanosclerosis involving the ossicular chain: mobility of the stapes in association with hearing results

CONCLUSION

The preoperative bone conduction level provides not only prognostic information but also information on the mobility of the stapes in tympanosclerosis. The surgical results depend upon the stapes mobility.

OBJECTIVES

We aimed to evaluate operative findings and hearing results of tympanosclerosis involving the ossicular chain, in order to understand the pathophysiology and to establish better surgical treatment of tympanosclerosis.

PATIENTS AND METHODS

Between January 1998 and March 2004, 29 patients (29 ears) with tympanosclerosis involving the ossicular chain underwent tympanoplasty at our hospital. Patients with myringosclerosis only, or with an associated cholesteatoma, were excluded from this study. The clinical and operational records and pre- and postoperative pure tone audiograms were reviewed retrospectively.

RESULTS

Intact canal wall tympanoplasty was applied to all 29 patients. A non-staged operation was performed on 21 patients, and a staged operation was performed on the remaining 8 patients. In 25 patients (86.2%), the sclerotic lesion of the ossicles was located in the epitympanum. In the remaining four, the sclerotic lamella coated only the ossicular chain. On average, the preoperative air conduction hearing level of 57.9 dB was significantly improved to 46.3 dB after tympanoplasty. The success rate of middle ear surgery was 65.5% (19 of 29 patients), according to the criteria of the Otological Society of Japan. In 16 patients (55.2%), the mobility of the stapes was preserved (group A), while in the remaining 13 patients (44.8%), the stapes was fixed (group B). The mean preoperative bone conduction of 25.5 dB in group A was significantly better than that of 37.2 dB in group B. The hearing result significantly improved in group A but not in group B. The success rates were 75% (12 of 16 patients) in group A and 53.8% (7 of 13 patients) in group B.

Congenital cholesteatoma clinical features and surgical results

We analyzed congenital cholesteatomas in 63 ears of 63 patients who were operated on over a 24-year period. We investigated the presenting symptoms, tympanic membrane findings, cholesteatoma morphology and location, associated anomalies of the ossicles, surgical methods, and outcome of treatment. The age of the patients ranged from 2 to 51 years (mean, 13.3 years), and the closed type of cholesteatoma and the open type were found in 57 ears and 6 ears, respectively. Seventy-three percent of the patients were 15 years or younger. Hearing loss was complained of as a presenting symptom by 60.3% of the patients. In particular, all the patients with the open type of cholesteatoma reported hearing loss as a chief complaint, and most of them had a normal tympanic membrane. Many of the cholesteatomas were located at or around the posterosuperior part of the tympanic cavity. The lesion was confined to the tympanic cavity in 26 (41.3%) ears and to the petrous apex in 1 (1.6%) ear. Advanced cholesteatoma that extended from the tympanic cavity into the mastoid antrum was seen in 35 (55.6%) ears, and multiple cholesteatoma was present in 1 (1.6%) ear. Associated anomalies of the ossicles were suspected in 8 (12.7%) of the 63 ears. Among patients with the open type of cholesteatoma, such anomalies were found in 3 (50.0%) of 6 ears. The super structure of the stapes was destroyed in 63.5% of the patients, so the columella on the foot plate method was most frequently used for ossiculoplasty, followed by the columella on the stapes method and the Wullstein type I method.

Resorption of auditory ossicles and hearing loss in mice lacking osteoprotegerin

Bones conduct sound in the middle ear. The three ossicles-the malleus, incus, and stapes-form a chain that transmits vibrations from the tympanic membrane to the oval window of the inner ear. Little is known about bone remodeling events in these ossicles and about potential effects of osteoporosis on hearing loss. Osteoclastic bone resorption is enhanced in Opg(-/-) mice lacking osteoprotegerin, which is a soluble decoy receptor for the osteoclastogenic cytokine RANKL. We asked whether auditory ossicles are resorbed in Opg(-/-) mice, and whether these mice suffer from impaired auditory function. All three ossicles in Opg(-/-) mice showed thinning, especially at the malleal manubrium and incus body. Most notably, unlike in the case in wild-type mice, the junction between the stapes and the otic capsule was fixed in Opg(-/-) mice, and the stapedial footplate was thinner and broader. Radiological analyses revealed that malleal cortical thickness was positively correlated with tibial bone mineral density in Opg(-/-) and control littermate mice. Furthermore, progressive hearing loss was detected in Opg(-/-) mice starting at 6 to 15 weeks of age. These data suggest that osteoprotegerin plays a crucial role in hearing by protecting the auditory ossicles and otic capsule from osteoclastic bone resorption.

Severe hearing loss in Dlxl mutant mice

The Dlx homeobox gene family participates in regulating middle and inner ear development. A significant role for Dlxl, in particular,has been demonstrated in the development of the middle ear ossicles, but the functional consequences of Dlx.l gene mutation on hearing thresholds has not been assessed. The present study characterizes auditory brainstem responses to click and tonal stimuli in a non-lethal variant of a Dlxl gene knockout. We found that peripheral hearing thresholds for click and tonal stimuli were significantly elevated in homozygous Dlxl knockout (Dlxl-/ ) compared to both heterozygous (Dlxl+/ ) and wild type (Dlxl+/+) mice. Thus, abnormal mor-phogenesis of the incus and stapes that has been documented previously with histological measures is now known to result in a severe peripheral hearing deficit.

Should We Use Ossicular Remnants in Ossicular Reconstruction following Cholesteatoma Removal?

The remnants of the acoustic ossicles have been used in ossicular reconstruction during mastoid surgery for many decades. The present study assessed the status of the acoustic ossicles in 114 patients (57 with cholesteatoma and 57 without) during surgery for chronic otitis media using the operating microscope. In 52 cases, the ossicles (malleus and/or incus) were assessed using both the surgical and scanning electron microscope in order to reveal any erosions and compare the findings. From the 57 operated ears with cholesteatoma, 45 (79%) had ossicular erosion whereas 12 (21%) did not. In the group of 57 operated ears with chronic otitis media without cholesteatoma, 33 (58%) had ossicular erosion whereas 24 (42%) did not. This difference was statistically significant (p = 0.02). With regard to the 52 operated cases who were studied with both microscopes, in the cholesteatoma patients the surgical microscope was not able to reveal any ossicular erosions in 39% of the cases, whereas the scanning electron microscope revealed moderate or severe erosions in the same ears. This suggests that the operating microscope is not reliable enough to determine if ossicular remnants can be used in ossicular reconstruction following cholesteatoma surgery. There is a considerable risk that epithelia or other cholesteatoma particles remain in the areas of erosions that cannot be seen with the operating microscope. The use of such ossicular remnants may lead to cholesteatoma recurrence and failures in mastoid surgery. Therefore, autoclaving or alternative prosthesis may be considered in such cases.

[Laser Doppler vibrometry: a new tool for diagnosing hearing loss with an intact eardrum]

The diagnosis of hearing loss with an intact eardrum frequently requires an entire battery of hearing tests, without the guarantee of an exact diagnosis. The techniques frequently provide only orientation for it, without establishing the site of the lesion and the etiology of the hearing loss. Laser Doppler vibrometry is a new technique, which has recently proved capable, of partially resolving this problem. The method is based on the study of the sound-induced vibration of the eardrum in humans in vivo, using a laser Doppler vibrometer. The method proved to be useful in the diagnosis of the pathology of the middle ear sound transmission system, avoiding the need for exploratory tympanotomy. Called "laser-audiometry", the method promises to become a new diagnostic tool for hearing impairment.

[Patients with chronic otitis media at the age below 16-year-old from data collected at Department of Otolaryngology Collegium Medicum Jagiellonian University between 2004-2006]

BACKGROUND

Otitis media is a frequent disease in childhood. Infections of ear in children depend on differences in anatomical structure. Clinical picture of otitis media is similar in all age groups.

THE AIM OF STUDY

We performed prospective analysis of patients at the age below 16-year-old treated surgically because of chronic otitis media between 2004-2006.

MATERIAL AND METHODS

250 operations of ear were performed in that period of time. We operated 28 patients below 16 year-old: 26 with chronic otitis media and 2 with otosclerosis.

RESULTS

The therapy gave positive results. In 3 cases destruction of bone of skull base was noticed. Delaminations were closed during ear operation successfully.

CONCLUSIONS

In children with chronic otitis media we use the same surgical procedures as in adults. We tend to make closed tympanoplasties in children. We should keep in mind possibility of asymptomatic lack of skull base bone as a consequence of chronic otitis media.

[Revision ossiculoplasty: anatomical and functional results]

OBJECTIVES

To analyse the anatomical and functional results after second-look ossiculoplasty using Titanium (TI) and Hydroxyapatite (HA) prosthesis and to study the prognostic factors for good functional results.

PATIENTS AND METHODS

Forty nine patients (19 men and 30 women) with an average age of 36 years were included in this study. The patients presented with anatomical and/or functional failures after a first ossiculoplasty and had a second-look intervention. The status of the first prosthesis and also the anatomical status of the middle ear and the remaining ossicular chain were described intra operatively. The functional and anatomical results were assessed 2 months after the second ossiculoplasty and during the most recent out patient clinic. Postoperative air conduction gain (ACG) and air bone gap (ABG) were calculated in average values using four frequencies: 0.5, 1, 2 and 4 kHz. The variables used in statistical analysis were the following: Tympanic membrane and preoperative middle ear status, the type of prosthesis (partial or total) and its material (TI and HA).

RESULTS

The average time to second-look operation was 18 months. The postoperative ABG did not show any significant statistic improvement and in several patients auditory function deteriorated in the operated ear The predictive factors for good functional results were: The integrity of the tympanic membrane, chronic otitis media without cholesteatoma, total prosthesis and HA prosthesis. If three of these factors were present, the postoperative ABG would always be less than 20 dB.

CONCLUSION

When selecting patients for second look ossibuloplasty it is important to understand the predictive facctors for good results. This will allow a full discussion of options, risks and morbidity with the patient.

Bone cement ossiculoplasty: incus to stapes versus malleus to stapes cement bridge

OBJECTIVE

In this study, our purpose was to evaluate results of our experience with bone cement repair of ossicular discontinuity between the incus and stapes and between the malleus and stapes.

METHODS

Medical records of patients who underwent surgery for chronic otitis media between March 2000 and December 2002 were evaluated retrospectively. Fifty-seven patients who underwent bone cement ossiculoplasty and had appropriate follow-up data were included in the study. Bone cement reconstruction of the ossicular chain was performed 1) from incus to stapes (I-S) in the absence of long arm or lenticular process of the incus and 2) from malleus to stapes (M-S) in the absence of the incus. The clinical data of the patients were evaluated by otoscopic examination and audiometry.

RESULTS

The graft take rate was 84.1%. I-S procedure was performed in 42 and M-S in 8 patients. Pre- and postoperative PTAs of all patients were compared, which showed a significant improvement in air PTA (p < 0.001) while bone PTA did not change (p > 0.05). In I-S and M-S groups, successful hearing restoration could be achieved in 78.6.1% and 87.5% of the patients, respectively. Hearing results of different aural pathologies (chronic otitis media and conductive hearing loss) and surgeries (tympanotomy and tympanoplasty with or without mastoidectomy) were not significantly different (p > 0.05).

CONCLUSION

Bone cement ossiculoplasty offers cost effective and significant improvement in conductive hearing loss.

[Bone ablation using ultrashort laser pulses. A new technique for middle ear surgery]

OBJECTIVES

Laser applications within the tympanic cavity area are widely accepted. Commonly used systems are CO(2), argon, KTP and erbium devices. The disadvantages are heat development and/or acoustic load of the inner ear. A new laser with ultra short pulses was examined concerning its ablation characteristics and tested for possible applications in the tympanic cavity.

METHODS

Investigations on human ossicles and porcine compacta were performed with a femtosecond laser in order to determine the ablation parameters. This included measurements of the dependency of the threshold energy on the pulse duration and the determination of the ablation ratio using different pulse energy levels. On the basis of histological slices the thermal damages of the bone were examined. Additionally, the processed samples were analyzed with an optical microscope and with a scanning electron microscope in order to evaluate the quality of the perforations.

RESULTS

The measurements showed that the threshold energy has a lower level than the threshold energy of the conventional laser systems. At a pulse duration of 180 fs the smallest fluence, with which an erosion can be achieved, is below 1 J/cm(2). With increasing pulse duration the necessary threshold energy also rises. Due to the low energy level necessary for ablation and the extremely short pulse duration, less thermal damage is induced to the surrounding bone tissue as compared to conventional laser systems. The analysis of the scanning electron microscope demonstrates the extreme precision of this laser system. The achieved accuracy of the incisions and drillings ranges in the microm-area.

CONCLUSIONS

The fs laser represents a new surgical tool for middle ear surgery. It works efficiently and in a touch-free procedure. Due to its high precision and the reduced side effects an advantage in the handling of bony structures is to be expected in relation to other laser systems. Apart from the perforation of the stapes footplate, in particular the handling and modelling of the incus, a further field of applications includes enhanced coupling, e. g. for implantable hearing aids and ossicular chain replacement prosthesis.

Pathology of the ossicular chain: comparison between virtual endoscopy and 2D spiral CT-data

OBJECTIVE

The purpose of this study was to assess the value of virtual endoscopy (VE) in the diagnosis of lesions of the ossicular chain and to compare virtual endoscopy and two-dimensional (2D) spiral computed tomography (CT) data.

STUDY DESIGN

Retrospective study.

SETTING

A university hospital.

PATIENTS

Fifty-eight patients with suspected ossicular chain lesions underwent a high-resolution CT of the temporal bone with both 2D data and VE before surgery.

MAIN OUTCOME MEASURES

Two views were chosen for VE. The CT data obtained (2D, VE, and both 2D and VE) were compared with the lesions noted during surgery.

RESULTS

In the diagnosis of dislocation of the ossicles or prostheses, VE seemed to be a better technique than 2D CT. Views chosen for the VE proved to be ineffective for diagnosing epitympanic fixations. VE was not adapted to the study of otosclerosis. We found it necessary to use the data provided by the addition to 2D CT data in the diagnosis of ossicular lysis and minor aplasia. Radiologic analysis of the lesions of the long process of the incus and the incudostapedial joint was improved by performing both 2D CT and VE. VE reconstruction of the stapes proved to be difficult, especially in cases of inflammation of the middle ear.

CONCLUSION

This study demonstrates the value of VE in the diagnosis of dislocation of the ossicles and ossicular prostheses. VE was less effective in diagnosing other pathologies of the ossicular chain.

Bone Destruction Resulting From Rupture of a Cholesteatoma Sac: Temporal Bone Pathology

OBJECTIVE

The purpose of the current study was to research the pathogenesis of bony destruction of cholesteatoma.

STUDY DESIGN

We conducted a case report.

SETTING

The study was performed at Fukushima Medical University.

PATIENTS

The first case involved a 21 trisomy, whereas the second case was cancer of the hypopharynx. Both cases showed cholesteatoma.

RESULTS

The following histopathologic findings in the temporal bones of cholesteatoma were obtained. Bony destruction in cholesteatoma was detected in the lesion of the rupture of the cholesteatoma sac. Epithelial debris of cholesteatoma was scattered throughout the rupture of the cholesteatoma sac. Rupture of the matrix was the result of a small abscess.

CONCLUSION

Rupture of the cholesteatoma sac was believed to have been a pathway of either endogenous substances from the matrix and/or epithelial debris of cholesteatoma.

Paraganglioma presenting as chronic otitis media with cholesteatoma: pitfalls and strategies

The coexistence of paraganglioma with cholesteatoma is a very rare clinical disorder. The clinical presentations are nonspecific. There may be radiological characteristics of either cholesteatoma or paraganglioma in the middle ear area, but the diagnosis of the coexistence of the 2 is usually made only postoperatively. Here is such a case that is made more interesting not only because it initially presented with conductive hearing loss but also because the clinical picture mimicked chronic otitis media. The patient underwent postauricular tympanomastoidectomy with extended facial recess approach to remove the tumor. No evidence of recurrence and complications were noted.

3D micro-CT images of ossicles destroyed by middle ear cholesteatoma

OBJECTIVES

To reconstruct the 3D structures of normal ossicles and ossicles destroyed by different cholesteatomas, and to compare the volume fractions of the two types of ossicles.

MATERIALS AND METHOD

Thirteen pathological ossicles from four kinds of middle ear cholesteatoma obtained during surgery were used. Normal ossicles harvested from cadaveric temporal bone specimens were used as controls. The structures of the ossicles were analyzed using micro-CT by filming 2D cross-sectional images perpendicular to the long axis, from which 3D images were reconstructed. The volume fraction was measured using a CT-Analyzer and Ant.

RESULTS

The volume fraction, indicating the relative strength of normal ossicles, was lower in the portion close to the articular surface. As the four types of cholesteatoma were found to express their patterns of destruction at various sites in the ossicles, they revealed a different volume fraction in each ossicle.

CONCLUSION

Our preliminary data on ossicular structure obtained using micro-CT will be helpful for elucidating the normal and pathological structure of ossicles and for the further development of artificial prostheses.

[Computed tomography (CT) of the temporal bone in diagnosis of acquired cholesteatoma of the middle ear]

The analysis of 51 CTs of the temporal bone in patients aged from 2 to 74 years with otitis media purulenta chronica, cholesteatoma has established that cholesteatoma of different location and severity has specific CT-symptoms. A reliable diagnostic key to CT-diagnosis of cholesteatoma is attic deformation due to destruction of the lateral wall by a soft tissue lesion, extension of the aditus to the antrum, the presence of the cavity with sclerotic walls in the antromastoid area, carious changes in the auditory ossicles, medial or lateral shift of the ossicles. CT registers carious alterations in the middle ear cavity walls including the roof and labyrinthine wall of the tympanic cavity. This allows diagnosis of a labyrinthine fistula and intracranial complications of cholesteatoma. CT well visualizes spread of cholesteatoma on the top of the pyramid. Age-related features of cholesteatoma are studied.

[Advantage of virtual endoscopy in the evaluation of the ossicular chain]

PURPOSE

Our study consists of a comparison of traditional computed tomography (CT) data sets with 2 views of virtual endoscopy in the preoperative evaluation of various diseases of the middle ear.

MATERIALS AND METHODS

We studied 59 patients, all sent for conductive hearing loss with normal eardrum who underwent a complete CT examination: axial helical acquisition and coronal incremental acquisition: virtual endoscopy with selection of two reproducible views: an external one of the auditory canal and a lower one of the hypotympanum. Reading was performed by 2 independent radiologists. All patients were subsequently operated by the same surgeon. Results were compared with surgical reports.

RESULT

Virtual endoscopy is valuable for the evaluation of ossicular and prosthesis dislocations, morphological anomalies of the malleus, incus, and stapes superstructure. Nevertheless, standard axial and coronal CT images remain necessary as confirmed by the poor results of virtual endoscopy in cases of attic obstruction, cholesteatomas and otospongiosis.

CONCLUSION

Virtual endoscopy is a valuable technique of the evaluation of some ossicular chain pathologies but it cannot be used alone.