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1.
Bone-conducted evoked myogenic potentials from the sternocleidomastoid muscle   总被引:10,自引:0,他引:10  
The aim of this study was to show that bone-conducted clicks and short tone bursts (STBs) can evoke myogenic potentials from the sternocleidomastoid muscle (SCM) and that these responses are of vestibular origin. Evoked potential responses to bone-conducted auditory stimuli were recorded from the SCMs of 20 normal volunteers and from 12 patients with well-defined lesions of the middle or inner ear or the VIIIth cranial nerve. The subjects, who had various labyrinthine and retro-labyrinthine pathologies, included five patients with bilateral profound conductive hearing loss, two with bilateral acoustic neuroma post-total neurectomy and five with bilateral sensorineural hearing loss. Air- and bone-conducted evoked myogenic potentials in response to clicks and STBs were recorded with surface electrodes over each SCM of each subject. In normal subjects, bone- and air-conducted clicks and STBs evoked biphasic responses from the SCM ipsilateral to the stimulated ear. The bone-conducted clicks evoked short-latency vestibular-evoked myogenic potential (VEMP) responses only in young subjects or in subjects with conductive hearing loss. STBs evoked VEMPs with higher amplitude and better waveform morphology than clicks with the same acoustic intensity. Patients with total VIIIth cranial nerve neurectomy showed no responses to air- or bone-conducted click or STB stimuli. Clear VEMP responses were evoked from patients with conductive or sensorineural hearing loss. It is concluded that loud auditory stimuli delivered by bone- as well as air conduction can evoke myogenic potentials from the SCM. These responses seem to be of vestibular origin.  相似文献   

2.
OBJECTIVES: To show that short tone bursts (STBs) evoke myogenic potentials from the sternocleidomastoid muscle (SCM) that are of vestibular origin. DESIGN: Evoked potential activity was recorded from the SCMs of normal volunteers and from patients with vestibulocochlear disorders. SETTING: This outpatient study was conducted at the Department of Otolaryngology, University of Tokyo, Tokyo, Japan. SUBJECTS: Nine normal volunteers and 30 patients (34 affected ears) with vestibulocochlear disorders were examined. INTERVENTION: Diagnostic. OUTCOME MEASURES: Sound-evoked myogenic potentials in response to STBs were recorded with surface electrodes over each SCM. Responses evoked by STBs in patients were compared with responses evoked by clicks. RESULTS: In all normal subjects, STBs (0.5, 1, and 2 kHz) evoked biphasic responses on the SCM ipsilateral to the stimulated ear; the same was true for clicks. Short tone bursts of 0.5 kHz evoked the largest responses, while STBs of 2 kHz evoked the smallest. In patients with vestibulocochlear disorders, responses to STBs of 0.5 kHz were similar to responses evoked by clicks. Thirty (88%) of the 34 affected ears demonstrated the same results with 0.5-kHz STBs and with clicks. Responses were present in patients with total or near-total hearing loss and intact vestibular function. Conversely, patients with preserved hearing but with absent or severely decreased vestibular function had absent or significantly decreased myogenic potentials evoked by STBs. CONCLUSIONS: Short tone bursts as well as clicks can evoke myogenic potentials from the SCM. Myogenic potentials evoked by STBs are also probably of vestibular origin.  相似文献   

3.
OBJECTIVE: The purpose of this study was to determine whether vestibular evoked myogenic potentials from the sternocleidomastoid muscle in response to bone-conducted clicks and short tone-bursts can be used to assess vestibular apparatus function in patients with conductive hearing problems, particularly bilateral external auditory canal atresia. DESIGN: Evoked-potential responses to bone-conducted auditory stimuli were recorded from the sternocleidomastoid muscle of 15 patients (11 male and four female, aged 4--20 years) with congenital bilateral atresia of the external auditory canal, with or without the middle ear anomalies. SETTING: This study was conducted in the outpatient clinic of the Tokyo University Hospital, Department of Otolaryngology, University of Tokyo. INTERVENTION: Diagnostic. OUTCOME MEASURES: Bone-conducted vestibular evoked myogenic potentials in response to clicks and short tone-bursts were recorded with surface electrodes over both sternocleidomastoids in each patient. RESULTS: In all patients, bone-conducted clicks and short tone-bursts evoked larger biphasic responses from the sternocleidomastoid ipsilateral to the stimulated ear. Short tone-bursts evoked vestibular evoked myogenic potentials with higher amplitude and better waveform morphology than clicks at the same subjective intensity. CONCLUSION: Loud auditory stimuli delivered by bone conduction can evoke myogenic potentials from the sternocleidomastoid. This method is a noninvasive, rapid, and convenient test for investigating the vestibular system function in patients with bilateral external auditory canal atresia, with or without the middle ear anomalies.  相似文献   

4.
OBJECTIVE: A large negative deflection with a 3-4 ms latency within the auditory brainstem response has been reported in some profound hearing loss ears under intense stimuli in adult subjects. The wave has been termed the N3 potential or acoustically evoked short latency negative response and it is assumed to be a vestibular-evoked potential. The purpose of the current study was to investigate the relationship between the vestibular-evoked myogenic potentials and the acoustically evoked short latency negative response in infants with a functionless cochlea and normal or impaired semicircular canal. METHODS: Seventeen 3 months old infants with profound bilateral sensorineural hearing loss had acoustically evoked short latency negative responses and vestibular-evoked myogenic potentials recorded and caloric tests performed. RESULTS: No spontaneous symptoms of vestibular dysfunction were found in the examined infants. ASNR with medium latency 3.3 ms and threshold value 80-90 dB normal hearing level was elicited from 10 ears. VEMPs were present in 12 ears. ASNRs and VEMPs were absent in two ears with normal response to caloric stimulation. No response to caloric stimulation was elicited from other two ears with normal saccular function. For the ears with absence of ASNR, four had normal VEMP and the rest were considered to have saccular afunction. Significant correlation was found between the presence of ASNRs and VEMPs. CONCLUSION: Acoustically evoked short latency negative responses could be a valuable tool for assessing vestibular function in infants with profound sensorineural hearing loss.  相似文献   

5.
In recent years it has been demonstrated that loud clicks generate short latency vestibular evoked myogenic potentials (VEMP). It has also been demonstrated that midline forehead skull tap stimulation evokes similar VEMP. In the present study, the influence of skull tap direction on VEMP was studied in 13 normal subjects and in five patients with unilateral vestibular loss. Gentle skull taps were delivered manually above each ear on the side of the skull. The muscular responses were recorded over both sternocleidomastoid muscles using skin electrodes. Among the normals, laterally directed skull taps evoked "coordinated contraction-relaxation responses", i.e. skull taps on one side evoked a negative-positive "inverted" VEMP on that side and a positive-negative "normal" VEMP on the other side. Among patients with unilateral vestibular function loss, skull taps above the lesioned ear evoked similar coordinated contraction-relaxation responses. However, skull taps above the healthy ear did not evoke that type of response. These findings suggest that laterally directed skull taps activate mainly the contralateral labyrinth.  相似文献   

6.
前庭诱发肌源性电位   总被引:3,自引:1,他引:2  
目的探讨用高强度短声刺激一侧球囊在双侧颈部屈肌(胸锁乳突肌)记录肌源性电位来反映人的前庭丘脑通路完整性的方法。方法实验中对27例正常人及25例末梢性前庭病变和15例重度感音神经性聋患者的前庭诱发肌源性电位进行了研究。记录电极分别放置在双侧胸锁乳突肌中部,通过标定耳机分别给双耳脉宽0.1ms的短声。结果在正常人颈部记录到的短潜伏期肌电位具有五个正负波,在同侧和对侧颈肌分别记录时各波的峰潜伏期无明显差别,而波幅有明显差异,即同侧记录时波幅明显高于对侧。pⅠ-nⅡ电位与冷热试验有很高的相关性。结论pⅠ-nⅡ电位可能源于球囊,暗示着一个快速的双突触的传导通路,其潜伏期代表着从感受器兴奋传到脑干再从桥脑到胸锁乳突肌运动神经元的中枢传导以及从运动神经元到肌肉的末梢传导的总和。  相似文献   

7.
Our aim is to compare short tone burst (STB)—and clicks—stimuli to evoke vestibular-evoked myogenic potentials (VEMPs) in healthy controls. A cross-sectional study in which VEMPs were measured in two sets of 185 and 55 normal volunteers by an air-conducted 500?Hz STBs and clicks, respectively. The test–retest reliability between different sessions was assessed in two subsets of 35 individuals. Moreover, 53 individuals were examined with both stimuli within the same session. Intraclass correlation coefficients (ICC) were used to assess reliability for P1 and N1 latencies, corrected amplitude and asymmetry ratio (AR). The results included that STBs produced a reliable response between different sessions (N?=?35; [ICC]?=?0.61–0.94, all p?<?0.0001). Although clicks produced a reliable response for P1 and N1 latencies and corrected amplitudes (ICC?=?0.62–0.74, all p?<?0.0001), the amplitude ratio showed a lower reliability [ICC?=?0.32 (?0.10 to 0.59)]. The amplitude of VEMP was consistently larger with 500?Hz STBs than clicks for a given sound pressure level. Within the same session, STBs evoked a response in 52/53 subjects (98%) whereas clicks evoked VEMPs only in 44/53 individuals (83%). Conclusions revealed that a 500?Hz STBs elicited consistently larger amplitudes, better reliability across recording sessions and fewer missing responses compared with click-induced VEMPs.  相似文献   

8.
Vestibular evoked myogenic potentials (VEMP) in response to sound stimulation (500 Hz tone burst, 129 dB SPL) were studied in 1000 consecutive patients. VEMP from the ear with the larger amplitude were evaluated based on the assumption that the majority of the tested patients probably had normal vestibular function in that ear. Patients with known bilateral conductive hearing loss, with known bilateral vestibular disease and those with Tullio phenomenon were not included in the evaluation. It was found that there was an age-related decrease in VEMP amplitude and an increase in VEMP latency that appeared to be rather constant throughout the whole age span. The VEMP data were also compared to an additional group of 10 patients with Tullio phenomenon. Although these 10 patients did have rather large VEMP, equally large VEMP amplitudes were observed in a proportion of unaffected subjects of a similar age group. Thus, the finding of a large VEMP amplitude in response to a high-intensity sound stimulation is not, per se, distinctive for a significant vestibular hypersensitivity to sounds.  相似文献   

9.
Vestibular evoked myogenic potentials (VEMP) are short latency electromyograms (EMG) evoked by high-level acoustic stimuli and recorded from surface electrodes over the tonically contracted sternocleidomastoid (SCM) muscle and are presumed to originate in the saccule. The present experiments examined the effects of click and tone-burst level and stimulus frequency on the latency, amplitude, and threshold of the VEMP in subjects with normal hearing sensitivity and no history of vestibular disease. VEMPs were recorded in all subjects using 100 dB nHL click stimuli. Most subjects had VEMPs present at 500, 750, and 1000 Hz, and few subjects had VEMPs present at 2000 Hz. The response amplitude of the VEMP increased with click and tone-burst level, whereas VEMP latency was not influenced by the stimulus level. The largest tone-burst-evoked VEMPs and lowest thresholds were obtained at 500 and 750 Hz. VEMP latency was independent of stimulus frequency when tone-burst duration was held constant.  相似文献   

10.
To clarify the laterality of acoustically evoked vestibulocollic reflexes with a short latency (vestibular evoked myogenic potentials, VEMPs). responses on the bilateral sternocleidomastoid muscles (SCMs) to unilateral acoustic stimulation were studied. Twenty-one healthy volunteers were enrolled. Surface electrodes were placed on the upper half of each SCM (active) and on the lateral end of the upper sternum (reference). Clicks and 500-Hz tone-bursts (95dB nHL) were used. All subjects showed positive-negative biphasic responses on the ipsilateral SCM by clicks and tone-bursts. Click-stimulation of 41 of the 42 ears did not evoke any response on the contralateral SCM. However, in one ear, positive-negative biphasic responses were evoked on the contralateral SCM. Recordings on the contralateral SCM by tone-bursts showed no response in 32 ears, small positive-negative biphasic responses in four ears, and small negative-positive biphasic responses in six ears. These findings show that VEMPs are ipsilateral-dominant, basically consistent with the hypothesis that they are of saccular origin.  相似文献   

11.
To clarify the laterality of acoustically evoked vestibulocollic reflexes with a short latency (vestibular evoked myogenic potentials, VEMPs), responses on the bilateral sternocleidomastoid muscles (SCMs) to unilateral acoustic stimulation were studied. Twenty-one healthy volunteers were enrolled. Surface electrodes were placed on the upper half of each SCM (active) and on the lateral end of the upper sternum (reference). Clicks and 500-Hz tone-bursts (95 dB nHL) were used. All subjects showed positive-negative biphasic responses on the ipsilateral SCM by clicks and tone-bursts. Click-stimulation of 41 of the 42 ears did not evoke any response on the contralateral SCM. However, in one ear, positive-negative biphasic responses were evoked on the contralateral SCM. Recordings on the contralateral SCM by tonebursts showed no response in 32 ears, small positive-nega-tive biphasic responses in four ears, and small negative-positive biphasic responses in six ears. These findings show that VEMPs are ipsilateral-dominant, basically consistent with the hypothesis that they are of saccular origin.  相似文献   

12.
We report vestibular evoked myogenic potentials (VEMPs) in 3 patients with bilateral profound hearing loss in order to confirm that they are not of cochlear origin. All of the 3 patients (31-year-old man, 67-year-old man and 47-year-old woman) had bilateral profound hearing loss. They were diagnosed as having congenital hearing loss, bilateral Ménière's disease and inner ear syphilis. Their pure-tone hearing ranged from 81 dB HL to nearly total hearing loss. Stimulation by click (95 dB nHL) evoked biphasic myogenic responses (p13-n23) on the sternocleidomastoid muscle ipsilateral to the stimulated ear. The ear in which the stimulation did not evoke biphasic myogenic responses did not have a caloric response either. These results suggested that VEMPs are not likely of cochlear origin but of vestibular origin.  相似文献   

13.
? A new cause of sound and pressure induced vertigo, superior canal dehisence, is described. ? Auditory manifestations include hyperacusis to bone‐conducted sounds and conductive hearing loss with normal acoustic reflexes. ? The diagnosis is reached by a directed history, documentation of upward and torsional nystagmus evoked by sound and pressure, and radiology. ? Acoustic reflexes and VEMP (vestibular evoked myogenic potentials) aid in the identification of patients with an apparent conductive loss with normal acoustic reflexes or have an asymptomatic dehiscense on radiology. ? Treatment involves avoidance of the precipitating stimuli. Surgical treatment, by resurfacing the dehiscence, is considered in patients with more severe symptoms.  相似文献   

14.
Vestibular evoked myogenic potentials in basilar artery migraine   总被引:8,自引:0,他引:8  
Liao LJ  Young YH 《The Laryngoscope》2004,114(7):1305-1309
OBJECTIVES/HYPOTHESIS: Because the sacculocollic reflex is a descending pathway passing through the territory of basilar artery, the aim of the study was to investigate whether hypoperfusion affects this pathway by applying vestibular evoked myogenic potential (VEMP) testing in patients with basilar artery migraine. STUDY DESIGN: A prospective study from May 2000 to April 2002. METHODS: Twenty patients were diagnosed as having basilar artery migraine according to the criteria of the International Headache Society and literature. Eight were male and 12 were female patients, and their ages ranged from 9 to 48 years (mean age, 40 y). Each patient underwent a battery of audio-vestibular tests. RESULTS: Electronystagmography disclosed abnormal eye tracking test in six patients (30%), and there were abnormal optokinetic nystagmus test results in nine patients (45%). Caloric test revealed canal paresis in seven patients, directional preponderance in four patients, and normal responses in nine patients (45%). Vestibular evoked myogenic potential testing disclosed absent vestibular evoked myogenic potentials in seven patients and delayed vestibular evoked myogenic potentials in two patients, with one patient showing absent vestibular evoked myogenic potentials on one side and delayed vestibular evoked myogenic potentials on the other side. The remaining 10 patients (50%) had bilateral normal vestibular evoked myogenic potentials. Five patients had preserved both caloric and VEMP test responses, six patients displayed absent caloric and VEMP test responses, and the remaining nine patients had either abnormal caloric test responses or abnormal vestibular evoked myogenic potentials, exhibiting a nonsignificant relationship between caloric test responses and vestibular evoked myogenic potentials. Relief of headache and vertigo was achieved after 3 months of medication. Ten asymptomatic patients with either absent or delayed vestibular evoked myogenic potentials before treatment underwent follow-up VEMP test, and nine patients (90%) displayed normal vestibular evoked myogenic potentials bilaterally. CONCLUSION: Vestibular evoked myogenic potential testing evaluates the sacculocollic reflex, which descends through the lower brainstem. Some patients with basilar artery migraine have absent or delayed vestibular evoked myogenic potentials, presumably because the descending pathway from the saccule through the brainstem to cranial nerve XI is interrupted, which is attributed to hypoperfusion in the territory of the basilar artery. After 3 months of medication, recovery of normal vestibular evoked myogenic potentials in an asymptomatic patient indicates reversible ischemia in the territory of the basilar artery.  相似文献   

15.
An enlarged vestibular aqueduct (LVA) is a common congenital inner ear anomaly responsible for some unusual vestibular and audiological symptoms. Most of the cases show bilateral early onset and progressive hearing loss in children. The gross appearance on CT scan of the inner ear is generally normal. However, precise measurements of the inner ear components reveal abnormal dimensions, which may account for the accompanying auditory and vestibular dysfunction. Despite extensive studies on hearing and the vestibular apparatus, saccular function is not studied. To our knowledge this is the first report of saccular malfunction in three patients with LVA by means of vestibular evoked myogenic potentials. Conventional audiograms revealed bilateral severe sensorineural hearing loss in two patients and mixed type hearing loss in one patient. Two of the patients complained about vertigo and dizziness but vestibular assessments of the patients showed normal results. The diagnosis had been made by high-resolution CT scans and MR images of the skull that showed LVA in the absence of other anomalies. The VEMP threshold measured from the ear with LVA in two patients with unilateral enlargement of the vestibular aqueduct was 75–80 dB nHL whereas the threshold from normal ears was 95 dB nHL. The third patient with mixed type hearing loss and bilateral LVA had VEMP responses despite a big air–bone gap in the low frequency range. The VEMP in this patient was greater in amplitude and lower in threshold in the operated ear (the patient had a tympanoplasty which did not improve her hearing). These findings and results of other patients with Tullio phenomenon and superior semicircular canal dehiscence, who also showed lower VEMP threshold, confirmed the theory of a ‘third window’ that allows volume and pressure displacements, and thus larger deflection of the vestibular sensors, which would cause the vestibular organ to be more responsive to sound and pressure changes.  相似文献   

16.
CONCLUSIONS: Bone-conducted vestibular evoked myogenic potentials (B-VEMPs) showed high specificity for the presence of vertigo in patients with unilateral chronic otitis media (COM). These results suggest that vestibular function can be evaluated with B-VEMPs, even in patients with conductive hearing loss. OBJECTIVE: The purpose of this study was to investigate the VEMPs induced by bone-conducted stimuli (B-VEMPs) in patients with conductive hearing loss due to perforated COM. SUBJECTS AND METHODS: The subjects were 48 patients with unilateral perforated COM and conductive hearing loss. The disequilibrium group consisted of 25 patients, and the non-disequilibrium group consisted of 23 patients. The control group comprised 35 healthy volunteers. B-VEMPs were stimulated with tone burst sound of 60 dB nHL and 250 Hz delivered from a bone vibrator and were recorded for each subject. The results of B-VEMP were compared between disequilibrium and non-disequilibrium groups. RESULTS: The mean interaural ratio was 16.5+/-12.1% in the control group, thus the normal range was <40.7%. Abnormal results were not found in any subject in the non-disequilibrium group but were found in 13 patients (54.0%) in the disequilibrium group (p<0.001). The ear with COM showed lower responses than the intact ear in all subjects with abnormal results.  相似文献   

17.
目的分析携带凝血因子C同源物(coagulation factor C homology,COCH)基因新突变的中国常染色体显性遗传非综合征型聋(autosomal dominant non-syndromic sensorineural hearing loss,DFNA)9家系成员的听力学及前庭功能特点。方法对家系成员进行纯音测听、听性脑干反应、耳蜗电图等听力学及计算机动态姿势描记、前庭诱发性肌源性电位、视眼动、前庭眼动等前庭功能检查。结果听力学检查提示该家系患者20~50岁出现以高频下降为主的进行性感音神经性聋,60~70岁进展为重至极重度全频听力损失。前庭功能检查提示随意抽取的家系中耳聋患者计算机动态姿势描记、视眼动、温度试验正常;前庭诱发性肌源性电位检查提示耳聋患者耳石功能异常;速度阶梯试验时间常数异常、正弦谐波试验增益和相位异常,提示耳聋患者水平半规管功能减弱。结论中国DFNA9家系的所有耳聋患者均无前庭功能损害的主诉,通过详尽的前庭功能检查提示位于COCH非胶原结构糖蛋白A型2结构域上的突变所导致的前庭功能损害明显轻于位于LCCL结构域上的突变。中国DFNA9家系的临床资料分析首次表明DFNA9存在基因型和表现型的相关性。  相似文献   

18.
Vestibular-evoked myogenic potentials in infancy and early childhood   总被引:3,自引:0,他引:3  
OBJECTIVE: Hearing impairment and the often concurrent loss of vestibular function, which is rarely assessed in infants, can both impair sensory integration critical to the development of normal motor coordination. This study demonstrates, for the first time, that vestibular function in infants can be noninvasively assessed using vestibular-evoked myogenic potentials (VEMPs). Our intentions were to demonstrate that VEMPs can be reliably recorded from neonates and to compare neonatal VEMPs with those obtained from normal adults. STUDY DESIGN: Prospective cohort study. METHODS: Myogenic evoked potentials induced by air- and bone-conducted auditory stimuli were recorded from the sternocleidomastoid muscles of 12 normal neonates and 12 neonates with various clinical findings. These included infants with bilateral atresia of the external auditory canals, Treacher-Collins syndrome, and neonates who failed universal neonatal screening. RESULTS: With the exception of one patient with hearing loss, reproducible biphasic VEMPs were recorded from the sternocleidomastoid muscle of all the infants using loud, short tone-burst sounds. CONCLUSIONS: The VEMP has characteristics that differentiate it from the postauricular response and the Jaw reflex. The VEMPs were dominant on the side ipsilateral to the stimulated ear. The overall morphology of the neonatal VEMP is quite similar to that of adults. The major neonatal differences are a shorter latency of the n23 peak and higher amplitude variability. Our results suggest that recording of the VEMP in neonates with various audio-vestibular problems provides useful information about vestibular function in this population and may provide information that leads to better care and rehabilitation for neonates at risk of developmental and motor system delay.  相似文献   

19.
Dehiscence of the superior semicircular canal is a 'new' vestibular entity. Among these patients, the vestibular evoked myogenic potentials (VEMP) in response to air-conducted sounds are large. In the present study, VEMP in response to bone-conducted sounds were studied in 5 normal subjects, in 3 patients after (unilateral) labyrinthectomy and in 4 patients with (unilateral) superior canal dehiscence syndrome. The bone-conducted sound stimulus was a 250- and a 500- tone burst delivered monaurally on the mastoid using standard bone conductors. Among the normals, bone-conducted sounds delivered monaurally caused VEMP bilaterally. There was, however, a transcranial attenuation for the 500-Hz stimulus, but less so for the 250-Hz stimulus. Among the patients with labyrinthectomy there were VEMP on the healthy side, but not on the lesioned side, irrespective of whether the bone-conducted sounds were presented behind the healthy or the operated ear. Among the patients with superior canal dehiscence syndrome, the VEMP on the affected side were larger than on the healthy side. This suggests that there is also vestibular hypersensitivity for bone-conducted sounds in these patients.  相似文献   

20.
Although superficial siderosis (SS) has been clinically characterized as a combination of sensorineural hearing impairment, cerebellar ataxia and pyramidal signs, precise evaluation of the function of the eighth cranial nerve has rarely been reported. The purpose of this study was to evaluate the audiological and vestibular function. We present a patient with complaints of progressive bilateral hearing loss and gait difficulty. We evaluated the audiological and vestibular functions with auditory brainstem responses and vestibular evoked myogenic potentials (VEMPs) by clicks and galvanic stimuli. The patient showed linear hypointensities surrounding the brainstem, cerebellum and the eighth cranial nerve on T2-weighted MRI images, which is characteristic of SS. Auditory brainstem response showed only wave I in the right ear and no response in the left ear. Click VEMPs and galvanic VEMPs showed no response on either side. The results of a neuro-otological examination suggested that both audiological and vestibular dysfunction in the patient with SS is of retrolabyrinthine origin.  相似文献   

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