The role of β-catenin deletion in Sox2-positive cells in inner-ear development and polarity regulation in mice / 复旦学报（医学版）

Objective To investigate the role of β-catenin,the core protein of canonical Wnt/β-catenin signaling,in the inner-ear development and polarity regulation.Methods β-catenin was conditionally deleted from precursor cells of inner-ear sensory epithelium (Sox2-positive cells) in embryonic mice.Morphological changes of the inner ear were observed.Immunofluorescence staining was performed to basilar membranes,utricles and saccules to observe the hair-cell changes in arrangement and polarity.Results Compared with the control group,knock-out of β-catenin in Sox2-positive cells resulted in smaller otic vesicles,cochleas and vestibules,and fewer hair cells (HCs) in vestibular sensory epithelium (P＜0.01).Stereocilium showed misorientation and kinocillia had a change in location and quantity in the cochlea.Scattered misorented HCs were also observed in the vestibule.Conclusions β-catenin is crucial for the development of inner ear and polarity manipulation of HCs in mice.The canonical Wnt/β-catenin signaling may be involved in the regulation of cochlea extension and planar cell polarity (PCP) of inner ear,which is known to be controlled by non-canonical Wnt/PCP signaling.

Clinical characteristics of patients with labyrinthine fistulae caused by middle ear cholesteatoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Labyrinthine fistula (LF) is a very common clinical complication mainly caused by middle ear cholesteatoma. Whether the presence of different degree LF caused by middle ear cholesteatoma aggravates neurosensory hearing loss (NSHL) and what is the degree of the hearing loss caused by LF were still under controversial. This study aimed to investigate whether the LF degree is correlative with the age distribution, disease duration and hearing loss degree for cholesteatomatous patients.</p><p><b>METHODS</b>The files of 143 patients with middle ear cholesteatoma were selected and reviewed in a retrospective study. Seventy-eight patients with LF were divided into three types according to the degree of destruction of labyrinth. Sixty-five patients without LF were randomly chosen for control. Then, we compared the clinical characteristics of patients with or without labyrinthine fistulae caused by middle ear cholesteatoma.</p><p><b>RESULTS</b>According to the study, cholesteatomatous patients with LF were older and suffered longer disease duration than those without LF. Hearing loss is severe with high frequencies both in patients with and without LF. Moreover, inner ear impairment is correlative with the degree of destruction in labyrinth, and more severe destruction in labyrinth follow the more severe symptoms correlative with inner ear impairment.</p><p><b>CONCLUSION</b>Surgical intervention should be performed as early as possible for these cholesteatomatous patients.</p>

Different sensitivities to rocuronium of the neuromuscular junctions innervated by normal/damaged facial nerves and somatic nerve in rats: the role of the presynaptic acetylcholine quantal release / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Muscles present different responses to muscle relaxants, a mechanism of importance in surgeries requiring facial nerve evoked electromyography under general anaesthesia. The non-depolarizing muscle relaxants have multiple reaction formats in the neuromuscular junction, in which pre-synaptic quantal release of acetylcholine was one of the important mechanisms. This study was to compare the pre-synaptic quantal release of acetylcholine from the neuromuscular junctions innervated by normal/damaged facial nerves and somatic nerve under the effect of rocuronium in rats in vitro.</p><p><b>METHODS</b>Acute right-sided facial nerve injury was induced by nerve crush axotomies. Both sided facial nerve connected orbicularis oris strips and tibial nerve connected gastrocnemius strips were isolated to measure endplate potentials (EPP) and miniature endplate potentials (MEPP) using an intracellular microelectrode gauge under different rocuronium concentrations. Then, the pre-synaptic quantal releases of acetylcholine were calculated by the ratios of the EPPs and the MEPPs, and compared among the damaged or normal facial nerve innervated orbicularis oris and tibial nerve innervated gastrocnemius.</p><p><b>RESULTS</b>The EPP/MEPP ratios of the three neuromuscular junctions decreased in a dose dependent manner with the increase of the rocuronium concentration. With the concentrations of rocuronium being 5 µg/ml, 7.5 µg/ml and 10 µg/ml, the decrease of the EPP/MEPP ratio in the damaged facial nerve group was greater than that in the normal facial nerve group. The decrease in the somatic nerve group was the biggest, with significant differences.</p><p><b>CONCLUSIONS</b>Rocuronium presented different levels of inhibition on the pre-synaptic quantal release of acetylcholine in the three groups of neuromuscular junctions. The levels of the inhibition showed the following sequence: somatic nerve > damaged facial nerve > normal facial nerve. The difference may be one of the reasons causing the different sensitivities to rocuronium among the muscles innervated by the normal/injured facial nerves and the somatic nerve. The results may provide some information for the proper usage of muscle relaxants in surgeries requiring electromyographic monitoring for the pre-surgically impaired facial nerves.</p>

Effect of REZ-I cochlear implantation on residual hearing in adult patients / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the effect of cochlear implantation with REZ-I straight electrodes on residual hearing of postlingually deafened adults, and to explore the audiologically safety and injury characteristics of cochlear implantation.</p><p><b>METHODS</b>Sixteen unilateral REZ-I (22 channels) cochlear implantation recipients from September 2009 to December 2009 were picked out. Their pre-and post-implantation audiometry data including pure-tone audiometry (PTA), auditory steady-state responses (ASSR), auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE) were retrospectively analyzed, in order to compare the change between pre- and post-implantation residual hearing.</p><p><b>RESULTS</b>Among the 12 recipients who had some measurable residual hearing before implantation, 5 (41.6%) patients had conserved some measurable hearing but the other 7 (58.4%) recipients had lost all measurable hearing after implantation on the implanted side. The implanted ears had an average PTA threshold drop of 9.5 dB HL and a statistically significant difference between pre- and post-implantation (P < 0.05) PTA thresholds in the frequencies of 250 Hz, 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz. Compared to non-implanted ears, the drop in 500 Hz and 1kHz had a statistically significant difference between pre- and post-implantation PTA thresholds (P < 0.05). The ASSR residual hearing threshold elevation were statistically significant (P < 0.05) between pre- and post-implantation ASSR at 250 Hz and 500 Hz on the implanted side, while the The ASSR residual hearing threshold elevation were statistically significant (P < 0.05) at 500 Hz when compared to non-implanted side. The difference of residual hearing between pre- and post-implantation was not statistically significant for both DPOAE and ABR.</p><p><b>CONCLUSION</b>There will be a certain degree of damage to residual hearing of the implanted side following REZ-I cochlear implantation.</p>

Normative data and clinical practice of sinusoidal harmonic acceleration test / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To establish the normative data of sinusoidal harmonic acceleration test (SHAT) and evaluate the value of clinical application.</p><p><b>METHODS</b>One hundred and twenty normal persons, 21 Meniere's disease patients, 2 bilateral vestibular peripheral lesion patients, 15 unilateral vestibular peripheral lesion patients and 10 central lesion patients were tested with SHAT.</p><p><b>RESULTS</b>The calibration time was longer in the older persons. The phase decreased with the frequency, and the gain increased with the frequency, but the reliability of the re-test of the phase was better in the lower frequency. The results of the 7 Meniere's disease patients without symptoms were normal, 14 patients post-attack revealed abnormal, 11 had phase abnormal, 3 had gain decrease, 10 revealed asymmetry and spontaneous nystagmus simultaneously, 8 patients had two parameters abnormal. The unilateral vestibular peripheral lesion patients showed 73% (11/15) phase abnormal, 67% (10/15) gain decrease and 40% (6/15) asymmetry, while 5/6 asymmetry patients had spontaneous nystagmus. The gain of the bilateral vestibular peripheral lesion patients showed severe decrease. The abnormal rate in central lesion patients were 70% (7/10) in phase, 20% (2/10) in gain and 40% (4/10) in asymmetry, but the patients with asymmetry had no spontaneous nystagmus.</p><p><b>CONCLUSIONS</b>The normal range of the phase, gain and asymmetry of SHAT is in narrow bandwidth. The phase is the most important abnormal sign.</p>

Langerhans cell histiocytosis of the temporal bone: 22 cases analysis / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To analyze the clinical manifestations, diagnosis, therapy and prognosis of Langerhans cell histiocytosis (LCH) of the temporal bone.</p><p><b>METHODS</b>Twenty-two patients with LCH of the temporal bone in our hospital were retrospectively summed up from January 1994 to January 2008. Following up 1 - 15 years, their clinical manifestations, diagnosis, therapy and prognosis were studied. Survival analysis and disease free survival Log-rank test were used.</p><p><b>RESULTS</b>Among 22 patients, 1 case belonged to the multisystem high risk group, 3 cases to the multisystem low risk group, and 18 cases to the single system group. The clinical characters were primarily the ear presentations, CT of the temporal bones showed extensive osteolytic destructions. The misdiagnosis rate was 72.7%. Twenty-two cases were received different combined modality therapies. Following up 1 - 15 years, 21 cases were survival and 1 case dead (4.5%), while 5 cases showed residual of insipidus, dwarfism, epilepsy or unilateral serious hearing loss (22.7%). For disease free survival curve, there was a significant difference between the multisystem group and the single system group (chi(2) = 5.87, P < 0.05).</p><p><b>CONCLUSIONS</b>As LCH of the temporal bone, the single system cases are predominant. The ear area clinical manifestations are primary. This disease is easily misdiagnosed. The therapy selection should rely on the involved systems of the disease. The prognosis of the single system group is much better than the multisystem group.</p>

Different prognostic characteristics between profound sudden sensorineural hearing loss and total sudden hearing loss / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To clarify the different prognostic characteristics between profound sudden sensorineural hearing loss (SSNHL) and total SSNHL.</p><p><b>METHODS</b>The patients with SSNHL who visited Eye Ear Nose and Throat Hospital from June 2007 to September 2008 were reviewed retrospectively. All the 204 patients, with pure tone average (PTA) threshold more than 90 dB, were enrolled and divided into two groups, including total SSNHL and profound SSNHL groups. The relationship between recovery rate and prognostic factors including the age, complications, time period between onset and therapy was analyzed.</p><p><b>RESULTS</b>There were 57 cases of total SSNHL and 147 cases of profound SSNHL in this series. Tinnitus was complained in more than 90% of the patients in both groups, which was higher than that of dizziness and ear fullness. Dizziness was present in 64.9% (37/57) patient with total SSNHL group and 45.6% (67/147) patients with profound SSNHL, which had significant difference between the two groups (χ(2) = 5.72, P = 0.017). The PTA threshold improvement in total SSNHL group and profound SSNHL group was (36.4 ± 19.3) dB and (40.2 ± 21.3) dB respectively, which was no significant difference between the two groups (t = 1.165, P = 0.245). The cured patients were all those received therapy within 1 week following the onset of SSNHL, which was of 2.6% (1/38) patients in the total SSNHL group and 14.3% (14/98) patients in the profound SSNHL group (P = 0.045). Furthermore, 3.5% (2/57) patients in total SSNHL group as well as 29.9% (44/147) patients in profound SSNHL group obtained a good result with PTA threshold ≤ 50 dB after therapy (χ(2) = 15.92, P = 0.001). In addition, the favorable prognosis was related with the onset-therapy time point(P = 0.001), but not related to the patients' age.</p><p><b>CONCLUSION</b>Profound SSNHL and total SSNHL though both with PTA threshold > 90 dB had significant differences recovery rate and need to be studied separately.</p>

Influences of two different endolymphatic infusion ways to cochlear morphology and function in guinea pigs / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To explore the influence of two different endolymphatic infusion ways on cochlear morphology and function.</p><p><b>METHODS</b>Forty healthy pigment guinea pigs (250 - 350 g) with normal Prey's reflex were divided into A and B group with 20 animals respectively. The right ears served as treated ears and the left ones as control ones. In group A, 5 microl of adenovirus 5-enhanced green fluorescence protein (Ad5-EGFP) suspension was infused into the scala media through an opened cochleostomy on the lateral wall of the scala media (LWS). In group B, the same volume of Ad5-EGFP suspension was infused into the scala media through punctured round window membrane and the basilar membrane (RBM). Cochlear morphology was examined under scan electric microscope and phalloidin staining was used to observe the hair cells in the infused ears after the animals were sacrificed. Auditory brainstem thresholds of the ears of all the animals were measured before and after treatment.</p><p><b>RESULTS</b>All the animals recovered well after operation. The holes on the lateral wall of the scala media and punctures on the round window membrane were healed completely. EGFP labeling appeared in the organ of Corti and lining wall of the stria vascularis indicated that adenovirus suspension was injected into the scala media using LWS (succeed in 14 animals accounted for 70%) and RBM (in 8 animals accounted for 40%) ways. Viruses were inoculated into the scala media with only locally inflammation reaction. In group A the hearing threshold decreased significantly in the treated ears compared with the control ears after the operation [(33.1+/-10.3) dB, (9.4+/-3.9) dB, F=46.34, P=0.0005]. However, in group B there was no significantly different between the treated ears and the control ears after the operation [(2.5+/-3.8) dB, (2.5+/-3.8) dB, F=0.00, P=1.000]. Phalloidin staining indicated that in group A the extension of hair cells loss was bigger than in group B. In some animals of two groups, EGFP labeling appeared in the extra-lymphatic system indicating that some of the injected suspension leaked out of the scala media.</p><p><b>CONCLUSIONS</b>Ad5-EGFP could be infused into the scala media through LWS or RBM and adenovirus could infect the lining cells of scala media and supporting cells in the basal membrane successfully without causing immunoreaction in the whole cochlea. LWS caused more hair cell loss and hearing loss than RBM. However, the cochlear morphology could be recovered completely after surgery. The positive inoculation rate was relatively higher that through LWS than that through RBM.</p>

CT multiplane reconstruction images of superior semicircular canal dehiscence syndrome / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the clinical application of multi-planar reformation (MPR) for the diagnosis of superior semicircular canal dehiscence syndrome.</p><p><b>METHODS</b>A retrospective study was conducted on 9 patients who were diagnosed with SSCD syndrome in the Otology and Skull Base Surgery group of Fudan University. Three radiologists analyzed all the patients' 0.75 mm-collimated axial and coronal images and 0.75 mm-collimated MPR images, and they came up with the same results.</p><p><b>RESULTS</b>There were 18 superior semicircular canal in the 9 patients, of whom 9 were intact and 9 were defective. All the defective superior semicircular displayed a definite dehiscence in all the MPR images, which indicated the sensitivity was 100%; however, 7 of the 9 defective superior semicircular canal were diagnosed as dehiscence in axial images, while 8 of the 9 were diagnosed in coronal images, but the sensitivities were 77.8% and 88.9% respectively. The results of the other 9 with intact superior semicircular canal displayed in the MPR, axial, and coronal images were also different. In the MPR images, they all displayed definite intact roof over the superior semicircular canal. There were 2 dehiscence in all axial and coronal images, and the specificities were 77.8%.</p><p><b>CONCLUSION</b>The MPR image is more useful in diagnosis of superior semicircular canal dehiscence syndrome than that of the routine axial and coronal images.</p>

Electromyographic monitoring of facial nerve under different levels of neuromuscular blockade during middle ear microsurgery / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The evoked electromyography (EMG) is frequently used to identify facial nerve in order to prevent its damage during surgeries. Partial neuromuscular blockade (NMB) has been suggested to favor EMG activity and insure patients' safety. The aim of this study was to determine an adequate level of NMB correspondent to sensible facial nerve identification by evaluating the relationship between facial EMG responses and peripheral NMB levels during the middle ear surgeries.</p><p><b>METHODS</b>Facial nerve evoked EMG and NMB monitoring were performed simultaneously in 40 patients who underwent tympanoplasty. Facial electromyographic responses were recorded by insertion of needle electrodes into the orbicularis oris and orbicularis oculi muscles after electrical stimulation on facial nerve. The NMB was observed objectively with the hypothenar muscle's twitching after electrical stimulation of ulnar nerve, and the intensity of blockade was adjusted at levels of 0, 25%, 50%, 75%, 90%, and 100% respectively with increased intravenous infusion of Rocuronium (muscle relaxant).</p><p><b>RESULTS</b>All of the patients had detectable EMG responses at the levels of NMB <or= 50%. Four out of forty patients had no EMG response at the levels of NMB >or= 75%. A significant linear positive correlation was present between stimulation thresholds and NMB levels while a linear negative correlation was present between EMG amplitudes and NMB levels.</p><p><b>CONCLUSIONS</b>The facial nerve monitoring via facial electromyographic responses can be obtained when an intraoperative partial neuromuscular blockade is induced to provide an adequate immobilization of the patient. The 50% NMB should be considered as the choice of anesthetic management for facial nerve monitoring in otologic microsurgery based on the relationship of correlation.</p>

Diagnosis of superior semicircular canal dehiscence syndrome / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To better understand superior semicircular canal dehiscence (SSCD) syndrome.</p><p><b>METHODS</b>A retrospective study was conducted on 6 patients who were diagnosed with SSCD syndrome in the Otology and Skull Base Surgery group of Fudan University. The clinical presentations including symptoms, signs, auditory tests and high resolution temporal bone computed tomography were reviewed.</p><p><b>RESULTS</b>Four patients presented with low frequency hearing loss while acoustic reflex responses were intact. Another patient was concomitance with chronic otitis media demonstrated profound sensorineural hearing loss. The sixth patient demonstrated normal hearing. Two patients also complained of autophony, but they were unable to tolerate their own voice. Five patients presented with vertigo while 2 patients were unable to tolerate the environmental noise. All patients showed slow component vertical torsional eye movement away from the effected eye which was induced by the presence of loud sound or pressure in the middle ear or valsalva maneuver. Four patients also demonstrated vertigo induced by the loud sound, 1 patient was induced head movement by 110 dB tone. All patients were revealed variable bone defect overlying on the SSC using high resolution temporal bone CT scan with SSC reformation.</p><p><b>CONCLUSIONS</b>The diagnosis of SSCD syndrome was established on both the presence of bone defect overlying superior semicircular canal which was demonstrated using high resolution temporal bone CT scan, and the presence of associated vestibular and auditory symptoms and signs.</p>

Uptake and accumulation of gentamicin by mouse hair cells from the cochlear explants in vitro / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the upstaging and accumulation of gentamicin by mouse hair cells in vitro.</p><p><b>METHODS</b>Cochlear explants were prepared from the microdissected neonatal mouse cochlea. Cochlear explants were cultured with gentamicin-Texas-red conjunction (GTTR) for different time. Laser confocal microscopy was used to observe the distribution of GTTR in the cochlear sensory cells after labeling with phalloidin-alexa-488.</p><p><b>RESULTS</b>Soon after culture, there was diffuse red staining all tissue cells in the explants. At later time the hair cells were more staining than other cells in the explants. There was no obviously accumulation of GTTR in the supporting cells. The peak level of fluorescent density was reached at 24 hours culture. The GTTR was seen in the infracuticular zone of the hair cells. There was still accumulation of GTTR in the hair cells of the explants after 7 days culturing.</p><p><b>CONCLUSIONS</b>GTTR and cochlea explants were useful methods to investigate the pharmacokinetics and mechanisms of gentamicin accumulation over time.</p>

Etiological factor analysis of facial nerve paralysis due to chronic inflammation of middle ear / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To discuss the etiological factors of facial nerve paralysis due to chronic inflammation of middle ear.</p><p><b>METHODS</b>This retrospective research included 41 patients operated for facial nerve paralysis due to chronic inflammation of middle ear. Careful exploration was made in facial canal in order to identify pathological tissue involvement. Pathological examination was performed in all operative specimens.</p><p><b>RESULTS</b>Four intact fallopian canals were observed. There was a defect on the fallopian canal in 37 patients (90%) and it was most commonly located on the tympanic segment of the canal (89%). Pathological report was cholesteatoma, granulation and tuberculosis, which was found in 24 cases (59%) 14 cases (34%) and 3 cases (7%), respectively.</p><p><b>CONCLUSIONS</b>Facial nerve paralysis due to chronic inflammation of middle ear was frequently relevant with cholesteatoma,the tympanic segment of the fallopian canal was most location to be involved in. Its major factor was the infection spreading along the nerve tissue, but not atrophy due to compression. The defect on the fallopian canal was not necessary for infection diffusion.</p>

Preparation of new protein carrier of vaccine against pneumococcal otitis media with genetic engineering technology / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To prepare pneumolysin as a new protein carrier of vaccine against otitis media with genetic engineering technology and establish the base of the study on pneumococcal conjugative vaccines.</p><p><b>METHODS</b>Genomic DNA was isolated from streptococcus pneumoniae. A pair of primers which included two restriction sites was designed based on the published pneumolysin gene sequence. The pneumolysin gene was amplified from pneumococcal DNA with PCR technology. The restriction enzyme digested fragment was linked into the cloning vector PET-28a and the recombinant plasmid DNA containing pneumolysin was then transfected into host cell E. coli JM109 (DE3).</p><p><b>RESULTS</b>DNA fragments were subcloned to construct the complete pneumolysin gene by a conventional coning and PCR. The inserted pneumolysin gene sequence was confirmed by DNA sequencing and the pneumolysin protein was successfully expressed. The relative molecular mass of the expressed product was 52 000. The expressed product amounted to 8% of the total host cell protein.</p><p><b>CONCLUSIONS</b>The pneumolysin gene was successfully cloned into host cell using genetic engineering technology. The recombinant pneumolysin was expressed and purified for preparation. This work laid a foundation of the preparation of pneumococcal conjugative vaccines.</p>

Experimental study on facial nerve regeneration by porous silk fibroin conduit / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility of using polyporus silk fibroin as a kind of novel material for facial nerve regeneration.</p><p><b>METHODS</b>The porous silk fibroin conduit was used in the reconstruction of a 5 mm facial nerve gap of SD rat. Chitosan conduit was taken as control group. General observation, electrophysiological study, histological study and image analysis were performed 2, 4, 6 and 8 weeks postoperatively.</p><p><b>RESULTS</b>The facial nerve of SD rat regenerated successfully as time passed through. Mean CAP percentage of regenerated nerve in SF conduit was 24.94% +/- 5.73% 8 weeks postoperatively, which had no statistical significance with that of chitosan conduit group (P = 1.125). And the average number of myelinated myelinated nerve fibers in SF conduit was 62. 5 +/- 6. 3, which had statistical significance with that in chitosan conduit group (P = 0.016).</p><p><b>CONCLUSIONS</b>The porous silk fibroin conduit could effectively repair facial nerve defect and improve peripheral nerve functional recovery.</p>

Distribution of gentamicin in inner ear after intratympanic gentamicin injection / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate uptake and accumulation of gentamicin by cells in the guinea pig inner ear after intratympanic injection using a fluorescent probe--gentamicin-Texas-red conjunction (GTTR).</p><p><b>METHODS</b>Adult guinea pigs (n = 80) were administered a single dose of GTrR to the middle ear cavity through the intact membrane and survived for 12 h, 24 h, 48 h, 3 d, 4 d, 7 d, 14 d and 28 d. The distribution of GTTR in the cochlear and vestibular cells was observed after staining with phalloidin-alexa-488. Texas Red and DMSO were injected into the tympanum as control.</p><p><b>RESULTS</b>Diffuse staining of gentamicin in the labyrinth was observed initially after local drug administration. At later time point the outer hair cells and sensory cells of vestibular organ were staining more densely than the support cells in the inner ear. The peak level of fluorescent density was reached 3 days after local injection. The GTTR was observed in the infracuticular zone.</p><p><b>CONCLUSIONS</b>GTTR was a potential fluorescent probe to investigate the pharmacokinetics and mechanisms of gentamicin accumulation in local application.</p>

Observation of auditory brainstem response and distortion product otoacoustic emission on the animal model of autoimmune auditory neuropathy / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To set up an animal model of autoimmune auditory neuropathy and to observe the auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) in guinea pigs.</p><p><b>METHODS</b>The spiral ganglion and the cochlear nerve were obtained and purified by electrophoresis from 250 normal guinea pigs. The purified cochlear nerve antigen was mixed with an equal volume of complete Freunds adjuvant for immunization. Seventy guinea pigs were divided into three groups: experiment group (50 guinea pigs), control group (10 guinea pigs), normal group (10 guinea pigs). ABR, DPOAE, serum IgG levels, and morphological changes of spiral ganglion cells and the cochlear nucleus were observed. The protein expressions of the antigen were examined by immunohistochemistry and the super-structure of the auditory nerve were observed.</p><p><b>RESULTS</b>The threshold of ABR response increased ranged from 10 to 25 dB in 32% (32/100 ears) of the guinea pigs. The peak latencies of waves I , III and the interpeak latency I approximately III were prolonged in the hearing loss group of guinea pigs. Prolonged peak latency of wave III was noted in hearing loss group at 2 and 3 weeks post immunization and slowly decreased to normal peak latency. The amplitude of DPOAE was no difference in the guinea pigs. The levels of serum IgG increased significantly compared with those of the control group. Inflammatory cell infiltration was observed in the cochlear nerve and the number of spiral ganglion cells detected. On the contrary, inflammatory cell infiltration was not observed in the cochlear nucleus. The cell densities and the across-sectional areas of neurons in anteroventral cochlear nucleus and posteroventral cochlear nucleus were no difference in the guinea pigs. The antigen protein distributed strictly in cochlear nerve and the spiral ganglion. Some demyelinated areas in cochlear nerve was observed in this group. The threshold of ABR response in 68% guinea pigs (68/100 ears) did not increase. The data of DPOAE and the serum IgG levels show no difference compared with the control group. There were not pathological observation in spiral ganglion cells, cochlear nucleus and cochlear nerve.</p><p><b>CONCLUSION</b>An animal model of autoimmune auditory neuropathy has been set up successfully and the character of the ABR and DPOAE was observed.</p>

Diagnosis and management of facial nerve neuromas / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To provide the experience for early diagnosis and management of facial nerve neuromas, and to discuss the clinic and imaging feature of facial nerve schwannoma and facial nerve fibroma in 22 cases.</p><p><b>METHODS</b>Twenty cases facial nerve schwannoma and two cases of facial nerve neurofibroma were diagnosed and reviewed retrospectively. Surgical removal were performed through the middle cranial fossa in 2 cases, through intratemporal approach in 8 cases, through intraparotid approach in 2 cases, and combined intra-temporal with out-temporal approaches in 10 cases. Seventeen cases underwent facial nerve graft for repairing a facial nerve defect. Great auricular nerve was used in 3 cases with intratemporal approach and 1 case with intratemporal combined intraparotid approach. Sural nerve graft was used in 5 cases with intratemporal approach and 8 cases with intra-temporal combined intraparotid approach. Two cases were employed two-stage facial muscle flap-plasty.</p><p><b>RESULTS</b>Facial nerve neuromas were totally removed in 21 cases and subtotal neuroma removed in 1 case. In these cases, 20 patients were no recurrence and 1 patient was lost follow-up. One patient with subtotal neuroma removal received Gamma Knife treatment before and after surgery, and this case was no recurrence. The CT imaging of the temporal bone showed that schwannoma was separated "white mass" with smooth margin along the region of facial nerve without intact canal. But neurofibroma locate in enlarge fallopian with intact canal. Magnetic resonance imaging had the advantage of evaluating all segments of the facial nerve and showed continuity of intratemporal and intraparotid mass with the facial nerve. Pathological results indicated that 20 cases were diagnosed as facial nerve schwannoma and 2 cases were neurofibroma.</p><p><b>CONCLUSIONS</b>Although tumors originating from the facial nerve are extremely rare, it is possible to make early diagnosis through finding clinical feature and imaging methods. Generally, systematic surgical approach for tumor removal and facial nerve reconstruction should be considered in the cases with facial neurinoma.</p>

Landmark of facial nerve in middle ear surgery / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To re-evaluate landmarks for facial nerve in middle ear surgery through temporal bone dissection and facial nerve surgery.</p><p><b>METHODS</b>Some relative landmarks were found through 44 facial nerves dissection in cadaver and 106 cases of facial nerve decompression surgery.</p><p><b>RESULTS</b>(1) Landmarks for vertical segment of the facial nerve: the vertical line in combined point between posterior and middle 1/3 horizontal semicircular canal clews the posterior edge of facial nerve; the prolong line of superior radian of incus short process clues to the anterior edge of the facial nerve, the facial nerve and horizontal semicircular canal are almost in the same plane. (2) Landmarks for horizontal segment of the facial nerve: the facial nerve tracks forward inferior to short process of incus and anterior to horizontal semicircular canal carina in 30 angel. The facial nerve, locating posterior and superior to cochleariform process and parallel with it, forms the step of middle-superior tympanic cavity and tracks forward to geniculate ganglion. (3) location of geniculate ganglion: The same distance prolong line of stapes head to cochleariform process clues to geniculate ganglion. (4) Location of the chorda tympani nerve: chorda tympani nerve, leaving tympanic sulcus at 3 clock of bone canaline left ear and at 9 clock of bone canaline right ear, tracks forward along tympani sulcus and then cross between long process of incus and manubrium. It lies in the border of pars tensa and pars flaccid and is about 5 - 8 mm from the stylomastoid foramen to where the chorda tympani nerve leaves the facial nerve. There is no difference of facial nerve structure in temporal bone dissection and in surgery.</p><p><b>CONCLUSIONS</b>The fixed landmarks of middle ear are the frame of reference of facial nerve, in which horizontal semicircular canal is most invariable; and the safety of surgery will be improved by the reference of the facial nerve.</p>

Clinical research about the distribution of perineural vascular plexus of the facial nerve / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To objectively evaluate the usefulness and the reliability of the perineural vascular plexus as a landmark for facial nerve as well as whether it will be a landmark for identification of the facial nerve in surgery for otology and neurotology by means of investigating the location of the facial nerve for prevention of iatrogenic facial palsy.</p><p><b>METHODS</b>Prospective case series were designed. Three hundred and eleven consecutive patients were studied which required tympanoplasty for chronic otitis media or microsurgery for facial nerve decompression and congenitally malformation of the ear from July 2002 to July 2005. All the patients were operated by the first author. Perineural vascular plexus as a landmark for identification of the facial nerve in surgery were observed to assess the utility.</p><p><b>RESULTS</b>The well recognized perineural vascular plexus were seen on the horizontal mesotympanic segment of the nerve in 95.8% of patients (298 cases), and only in 4.2% of the patients (13 cases), the vessel plexus was difficult to identify. The 95% confidence interval was from 93.6% to 98.0%.</p><p><b>CONCLUSIONS</b>The vascular plexuses around or over the horizontal portion of the facial nerve provide an early and direct indicator of the location of the facial nerve. The perineural vascular plexus could be a dependable and reliable landmark for the identification the horizontal part of the facial nerve in surgery for otology and neurotology.</p>