Hyun Woo Lim

Ulsan University Hospital, Urusan, Ulsan, South Korea

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Publications (20)25.28 Total impact

  • Hyun Woo Lim, Ji Won Lee, Jong Woo Chung
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    ABSTRACT: We undertook an animal study to investigate the functional and histological changes that occur in the normal hearing ear of following acoustic trauma. As an animal model of unilateral hearing loss, the right ears of CBA mice were deafened by cochlear destruction at 6 weeks of age (SSD group). The control groups included mice that underwent a sham surgery, and mice that were exposed to noise binaurally and monaurally (by plugging the right ear completely). At 10 weeks of age, all mice were exposed to acoustic trauma (110 dB sound pressure level for 1 hour) that induced a transient threshold shift (TTS). Changes in the hearing thresholds of the left ear were assessed over the next 4 weeks by measuring the auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). Following the noise exposure, the SSD group showed a permanent threshold shift (PTS) of about 10 dB, whereas the other groups showed full recovery from the TTS. The threshold of the DPOAEs of the left ears were increased after noise exposure but returned to normal in all groups, with no significant differences among the groups. Histological evaluation showed no apparent cellular loss or apoptosis in the left ears of all groups, including the SSD group. These results suggest that normal hearing ears are more vulnerable to acoustic trauma following contralateral unilateral cochlear ablation. This increased vulnerability may be due to damaged neural structures.
    The Annals of otology, rhinology, and laryngology 04/2014; 123(4):286-92. · 1.21 Impact Factor
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    ABSTRACT: The purpose of this study was to estimate the rates of functional recovery of the facial nerve and of total tumor resection in patients who undergo short anterior rerouting and long anterior rerouting of the facial nerve in removal of skull base tumors. We retrospectively collected data on 37 patients with skull base tumors who underwent facial nerve rerouting during the procedure for tumor removal. Information on the rerouting technique, the completeness of tumor resection, and changes in facial nerve function were obtained from the medical records. Rerouting techniques were classified as short anterior rerouting or long anterior rerouting. Ten of 16 patients (62.5%) in the group with short anterior rerouting showed postoperative facial palsy, and all completely recovered within 1 year. In the group with long anterior rerouting, 18 of 21 patients (85.7%) showed postoperative facial palsy, and recovery to a preoperative level of facial function was found in 10 patients at 1 year of follow-up. Total tumor resection was possible in 94% and 81% of patients with short rerouting and long rerouting, respectively. The mean operation time was not significantly related to the postoperative recovery of facial function. Short rerouting techniques, when appropriately chosen on the basis of tumor and patient characteristics, offer excellent preservation of facial function and tumor resection, comparable to those of long rerouting techniques.
    The Annals of otology, rhinology, and laryngology 02/2014; 123(2):141-7. · 1.21 Impact Factor
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    ABSTRACT: Objectives: Hearing loss can be associated with a decrease in cerebrospinal fluid (CSF) pressure because changes in CSF pressure induce changes in perilymph pressure. Hearing loss after neurosurgical procedures have been reported but clinical information on hearing loss after the placement of ventriculoperitoneal (VP) shunts, the most commonly used CSF shunt for hydrocephalus patients, is limited. This study is aimed to show the relationship between VP shunt and hearing loss. Study Design: Prospective study. Methods: Pure tone threshold and electrocochleography were preoperatively performed in 9 patients (18 ears) undergoing elective VP shunt placement. Five-day and 1-month post-shunt placement hearing thresholds were compared with baseline data. A correlation analysis was conducted between the threshold and summating potential/action potential (SP/AP) ratio changes at 5 days and 1 month after shunt placement. Cochlear aqueduct dimensions measured by high-resolution computed tomography were compared between ears with and without hearing loss. Results: About 40% of subject ears showed hearing loss with a threshold elevation of at least 15 dB in one or more frequencies. After VP shunt placement, the mean threshold of all ears showed a significant increase in most frequencies and the pure tone average. The change in the SP/AP ratios was significantly correlated with the change in the pure tone average at both 5 days and 1 month after shunt placement. Cochlear aqueduct dimensions were not correlated with hearing loss occurrence. Conclusions: Hearing thresholds may increase following VP shunt placement, possibly due to secondary endolymphatic hydrops.
    The Laryngoscope 12/2013; · 1.98 Impact Factor
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    ABSTRACT: Matrix metalloproteinases (MMPs) 2 and 9 are a group of Zn2+-dependent endopeptidases to remodel the extracellular matrix. The association of these 2 endopeptidases with the development of morphologic changes in nasal polyps was previously described. To determine whether MMP-2, MMP-9, and tissue inhibitor of MMP-1 (TIMP-1) play a role in the recurrence of nasal polyps. To compare MMP-2, MMP-9, and TIMP-1 expression in recurrent vs nonrecurrent polyps, nasal polyps (NPs) and recurrent nasal polyps (RNPs) were obtained from 15 NP patients with chronic rhinosinusitis (CRS) undergoing endoscopic sinus surgery (ESS) and 15 RNP patients with CRS undergoing revision ESS. Fifteen specimens of inferior turbinate mucosa from patients undergoing nasal septal surgery were used as control. Through real-time polymerase chain reaction and immunohistochemistry, MMP-2, MMP-9, and TIMP-1 expressions were measured among controls, NP patients, and RNP patients. Expression of MMP-9 messenger RNA in the NP patients was significantly higher than in the controls. In addition, expression of MMP-9 messenger RNA in the RNP patents was significantly increased compared with NP patients. With immunohistochemistry, a more increased expression of MMP-9 was observed in NP patients than controls. Expression of MMP-9 in RNP patients was also significantly high compared with NP patients, particularly in stroma. Expression of MMP-9 is increased in NP patients, and it is so more in the mucosa of RNP patients. Increased expression of MMP-9 is particularly found in the stoma of RNP patients, and it may contribute to the recurrence of NP.
    Annals of allergy, asthma & immunology: official publication of the American College of Allergy, Asthma, & Immunology 09/2013; 111(3):205-10. · 3.45 Impact Factor
  • Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 05/2013; · 1.44 Impact Factor
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    ABSTRACT: OBJECTIVE: The aim of this study was to characterize the various bony anomalies of the inner ear in patients with unilateral sensorineural hearing loss using high-resolution temporal bone computed tomography and establish the relationship between hearing and the diameter of the bony cochlear nerve canal. METHODS: We performed a retrospective review of 51 patients (mean age 11 years, range 0-20 years, 27 boys, 24 girls) who were diagnosed with unilateral sensorineural hearing loss with an audiogram. Coronal and axial diameter of the inner ear structures, including the internal auditory canal, bony cochlear nerve canal, and each turn of the cochlea and semicircular canals, were measured with high-resolution temporal bone computed tomography. The mean values (±2 standard deviations) were calculated and compared between sensorineural hearing loss and normal ears, and between narrow bony cochlear nerve canal and normal bony cochlear nerve canal ears. Bony cochlear nerve canal atresia/stenosis was defined as a value less than 1.4mm in axial images. RESULTS: The diameter of the bony cochlear nerve canal was significantly smaller in sensorineural hearing loss ears than in normal ears (p<.05). Associated inner ear anomalies, such as IAC stenosis (24%), cochlear hypoplasia (7-17%), and narrow semicircular canal bony island (8%) were only observed in the narrow bony cochlear nerve canal group. This group also showed statistically significant, severe to profound hearing loss compared to the normal bony cochlear nerve canal group (p<.05, R(2)=12.8%). CONCLUSIONS: Most (57%) of the unilateral sensorineural hearing loss ears had bony cochlear nerve canal stenosis/atresia and this group showed associated inner ear anomalies. When the diameter of the bony cochlear nerve canal was less than 1.4mm, pure tone audio averages were more than 70dB HL in most ears.
    International journal of pediatric otorhinolaryngology 01/2013; · 0.85 Impact Factor
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    ABSTRACT: Objective We aimed to determine whether abnormalities in outer hair cell (OHC) function were related to tinnitus through interaural comparison of distortion product otoacoustic emissions (DPOAEs).Study DesignCross-sectional study.SettingTertiary care university teaching hospital.ParticipantsTwenty-seven patients with unilateral tinnitus and pure-tone average of both ears ≤25 dB hearing loss (HL) at 500, 1000, 2000, and 4000 Hz were included.Subjects and Methods Pure-tone thresholds observed at 500 to 16,000 Hz and DPOAE amplitudes at f2 frequencies of 1001 to 6348 Hz were compared between the tinnitus ears and nontinnitus ears in patients with unilateral tinnitus.ResultsThe pure-tone averages (13 ± 6 dB HL) in the nontinnitus ears were similar to those (15 ± 6 dB HL) in the tinnitus ears. There were no differences in pure-tone averages at all frequencies tested. While the DPOAE amplitudes measured at f2 frequencies of 1001 to 3174 Hz in tinnitus ears were not different from those in the nontinnitus ears, the tinnitus ears showed significantly reduced DPOAE amplitudes when compared with the nontinnitus ears at frequencies of 4004 to 6348 Hz.ConclusionOHC dysfunction was correlated with tinnitus at high frequencies, and DPOAE amplitudes can provide additional information about cochlear dysfunction, which is complementary to pure-tone audiometry.
    Otolaryngology Head and Neck Surgery 11/2012; · 1.73 Impact Factor
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    ABSTRACT: OBJECTIVE: To verify that tinnitus itself could disturb speech perception and to evaluate the effects of masking noise on speech perception ability in the patients with normal hearing but unilateral chronic tinnitus using the hearing in noise test. STUDY DESIGN: Prospective, nonrandomized study. MATERIALS AND METHODS: Between June 2009 and May 2011, we enrolled 20 patients with normal hearing and subjective unilateral tinnitus that had persisted for more than 12 months, along with 20 healthy controls of the same age. All subjects were evaluated using audiologic examinations, the tinnitus handicap inventory, and the Korean version of the Hearing in Noise Test (K-HINT) to assess characteristics of tinnitus and speech perception ability in various noisy situations. RESULTS: Reception threshold for speech (RTS) in a quiet environment and signal-to-noise ratio (SNR) in various conditions of noise were significantly higher in the tinnitus than in the control group, regardless of whether noise came from the front, right, or left (p < 0.05). When the tinnitus group was subdivided according to the site of noise exposure, the mean SNR of the contralateral noise group was -7.9 ± 1.4 dB, which was significantly higher than the ipsilateral noise (-9.1 ± 1.8 dB) or control group (right, -10.0 ± 0.6 dB; left, -10.1 ± 0.5 dB) (p < 0.05). In addition, there was no significant difference between ipsilateral noise and control groups. CONCLUSION: From this study, we showed that tinnitus itself could adversely affect speech perception ability by increasing both RTS and SNR in the tinnitus patients in comparison with healthy controls. In addition, we suggest that proper level of noise on the site of tinnitus might be helpful to increase speech perception in the patients who experience chronic subjective tinnitus.
    Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 09/2012; · 1.44 Impact Factor
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    ABSTRACT: To investigate the validity of newborn hearing screening protocol using automated auditory brainstem response (AABR) with a confirmation method using click auditory brainstem response (ABR) and to evaluate changes in hearing status of infants with confirmed congenital hearing loss. Neonates in the well-baby nursery were screened by staged AABR. Subjects whose final AABR result was "refer" were tested by diagnostic click ABR and 226 Hz tympanometry within 3 months of age. Changes in hearing status of subjects with confirmed hearing loss were analyzed by follow-up ABR at 3-6 month intervals. Of the 12,193 healthy babies born during this period, 10,879 (89.22%) were screened by AABR. Of 10,879 neonates screened by AABR, 148 (1.36%) were "referred"; of these, 45 subjects showed ABR thresholds over 30 dB nHL in at least one ear. Thirty-four subjects underwent serial follow-up ABR tests, with 11 (32.4%) found to have normal ABR thresholds. Most subjects with mild to moderate hearing loss were found to be normal before 1 year of age, whereas all infants with severe or profound hearing loss were identified as having congenital hearing loss. The referral rate and the positive predictive value of our protocol were acceptable. We have also found here that substantial temporary hearing loss can be included in the first confirmative diagnosis. Temporary hearing loss of our study on follow-up give emphasis to need of further differentiation using the testing for bone conduction and middle ear status.
    Clinical and Experimental Otorhinolaryngology 06/2012; 5(2):57-61. · 0.88 Impact Factor
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    ABSTRACT: Peroxisome proliferator activated receptor-γ (PPAR-γ), a member of the nuclear hormone receptor superfamily, plays an important role in the regulation of mucosal inflammation. The aim of this study was to investigate the anti-inflammatory effect of a PPAR-γ agonist, ciglitazone, on cigarette smoke solution (CSS)-induced inflammation in human middle ear epithelial cell lines (HMEECs). HMEECs with or without ciglitazone pre-treatment were exposed to CSS in order to induce the inflammatory response. The suppressive effect of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and cyclooxygenase-2(COX-2), were evaluated using real-time polymerase chain reaction and Western blotting. Stimulation with CSS at 40 μg/ml for 6 h resulted in a 4.1-fold increase in the expression of TNF-α mRNA in the HMEECs. CSS-induced up-regulation of TNF-α mRNA was decreased by more than 2.8-fold in cells pre-treated with ciglitazone. The up-regulation of COX-2 mRNA and increased COX-2 protein expression induced by CSS were also inhibited by more than 3.7-fold with ciglitazone pre-treatment. These findings suggest that the inflammatory response induced by CSS could be inhibited by ciglitazone, a PPAR-γ agonist, in HMEECs. As such, PPAR-γ agonists may have therapeutic potential for the treatment of otitis media.
    International journal of pediatric otorhinolaryngology 05/2012; 76(8):1136-9. · 0.85 Impact Factor
  • Joong Ho Ahn, Hyun Woo Lim, Hye-Ran Hong
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    ABSTRACT: To evaluate the anti-adhesive and anti-inflammatory effects of sodium hyaluronate-carboxymethylcellulose (HA-CMC) on postoperative hearing improvement and complications during tympanomastoid surgery. Prospective controlled clinical trial. We evaluated 287 patients who underwent type I tympanoplasty, with or without canal wall up mastoidectomy, between January 2007 and June 2010. Postoperative hearing and complications were compared in the 143 patients who received Gelfoam soaked with HA-CMC during myringoplasty and the 144 patients who received Gelfoam only. There were no significant between-group differences in sex, age, and preoperative hearing status. However, average postoperative air-bone gap (13.7 ± 8.5 dB vs. 17.2 ± 9.9 dB) and the number of air-bone gaps smaller than 10 dB (40.6% vs. 24.3%) were significantly improved in the HA-CMC compared with the control group. In addition, the rates of re-otorrhea, reperforation of the tympanic membrane (TM), postoperative TM adhesion, and reoperation were lower in the HA-CMC than in the control group without significances. These findings suggest that combined application of Gelfoam with HA-CMC may be beneficial in patients undergoing tympanomastoid surgery.
    The Laryngoscope 02/2012; 122(4):912-5. · 1.98 Impact Factor
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    ABSTRACT: Acute otitis media (OM) is a common pediatric disease. Recent research into the pathogenesis of OM has focused on oxidative damage, induced by oxygen free radicals, to the middle ear mucosa along with inflammation. Caffeic acid phenethyl ester (CAPE) is a biologically active ingredient of propolis honey bees, with antioxidative and anti-inflammatory activities. The effect of CAPE on hydrogen peroxide (H(2)O(2))-induced inflammatory and oxidative reactions in the middle ear is still not known. The aim of this study was to evaluate the anti-inflammatory and antioxidative effects of CAPE on cultured human middle ear epithelial cells (HMEECs). The inflammatory injury of H(2)O(2) and the anti-inflammatory effect of CAPE were determined by measuring levels of pro-inflammatory cytokines (tumor necrosis factor (TNF)-α and COX-2) with real-time reverse transcription polymerase chain reaction and Western blot analysis. Oxidative stress induced by H(2)O(2) and antioxidative effects of CAPE were evaluated directly by reactive oxygen species (ROS) production using flow cytometric analysis of 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate, acetyl ester (CM-H(2)DCFDA), and indirectly by the expression of superoxide dismutase (SOD) using Western blot analysis. The effect of CAPE was compared with N-acetyl cysteine (NAC) which has well-known antioxidative and anti-inflammatory effects. CAPE significantly inhibited H(2)O(2)-induced upregulation of TNF-α and COX-2 expression in a dose and time dependent manner. ROS accumulation induced by H(2)O(2) stimulation was decreased by CAPE pretreatment. Induced SOD expression after H(2)O(2) stimulation was diminished by CAPE pretreatment. The anti-inflammatory and antioxidative effects of CAPE were similar to those of NAC. These findings suggest that inflammation induced by H(2)O(2) can be inhibited by CAPE via inhibition of the expression of pro-inflammatory cytokines such as TNF-α and COX-2. Furthermore, CAPE has antioxidative effects, which decreases the need for endogenous SOD expression.
    International journal of pediatric otorhinolaryngology 02/2012; 76(5):675-9. · 0.85 Impact Factor
  • Hyun Woo Lim, Tae Hyun Yoon, Woo Seok Kang
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    ABSTRACT: The clinical features and patterns of growth, relative to age, were examined in patients with congenital cholesteatoma to investigate disease progression and site of origin. We retrospectively reviewed 72 children younger than 15 years with intraoperatively confirmed congenital cholesteatoma diagnosed using the inclusion criteria of Levenson et al. Patient demographics, history, and otoscopic and operative findings were evaluated. Correlation between mass volumetric and operation age was analyzed in patients with closed-type masses. Parameters of disease extent of middle ear quadrant, ossicular erosion, attic involvement, invasion of the mastoid cavity, and type of mass were assessed relative to age at operation. Mean patient age was 63.1 months (range, 20-179 months), with 51 patients (70.8%) being asymptomatic and diagnosed incidentally. Nineteen patients (26.4%) had closed-type cystic masses, and 53 (73.6%) had open-type lesions. The volume of closed-type masses was linearly correlated with age at operation. Logistic regression showed that increased age at operation was associated with a lower proportion of anterosuperior quadrant lesions, resulting in uncertainty about the site of origin. The possibility of open-type masses also increased according to age at operation. Congenital cholesteatoma shows growth and extension over time. Early detection and intervention are necessary to avoid advanced disease.
    American journal of otolaryngology 02/2012; 33(5):538-42. · 0.77 Impact Factor
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    ABSTRACT: Despite complaints of dizziness, some patients with unilateral compensated vestibular weakness show normal results on Sensory Organization Test (SOT), which is being widely used for the evaluation of vestibular function compensation. The head shake-sensory organization test (HS-SOT) has been suggested to increase the sensitivity of SOT. In HS-SOT, the patient is required to shake head under Conditions 2 and 5 of traditional SOT. However, the sensitivity of HS-SOT remains unelucidated in patients with vestibular neuritis. The aim of this study was to determine the sensitivity of HS-SOT and SOT and compare them with the Dizziness Handicap Inventory (DHI) in detecting balance problems in patients with vestibular neuritis complaining of dizziness. Tertiary referral center. A prospective analysis was conducted on all vestibular neuritis patients between September 2009 and April 2011. Thirty-two patients with uncompensated vestibular neuritis were enrolled in this study. Patients with acute symptoms of dizziness, orthopedic problems, or any other severe underlying conditions were excluded. Equilibrium and vestibular scores of SOT and equilibrium score ratios of HS-SOT and DHI were obtained from each patient after 1 week and 1, 2, and 6 months of the first attack of vestibular neuritis. HS-SOT is more correlated with the DHI than SOT by periods. One month after vestibular neuritis, the correlation between DHI and SOT, HS-SOT Conditions 2 and 5 were -0.301, -0.385, and -0.625, respectively. Six months after vestibular neuritis, the correlation between DHI and SOT, and HS-SOT Conditions 2 and 5 were -0.053, -0.337, and -0.394, respectively. HS-SOT was more sensitive than SOT during the compensation of vestibular neuritis. Specifically, during the compensation of vestibular neuritis, HS-SOT Condition 5 was more correlated with DHI than HS-SOT Condition 2. The results suggest that HS-SOT provides more useful measures for the evaluation of vestibular compensation in vestibular neuritis.
    Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 12/2011; 33(2):211-4. · 1.44 Impact Factor
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    ABSTRACT: This study investigated the effect of a zinc-deficient diet on the hearing in CBA mice and aimed to verify whether this hearing change is reversible by supplementation of zinc afterwards. We assessed hearing through an auditory brainstem response (ABR) with tone burst stimulation in 4, 8, 16, and 32 kHz and distortion product otoacoustic emissions in 5.6, 8, 11.3, and 16 kHz every week. The ABR threshold started to increase after 4 weeks on a zinc-deficient diet. The difference in the threshold between control and zinc-deficient animals became greater over time and plateaued at about 6 weeks. The ABR threshold differences between control and zinc-deficient mice were greater at higher frequencies. Four weeks of normal diet, following 8 weeks of a zinc-deficient diet, restored the ABR threshold to normal at all measured frequencies. Zinc-deficient mice did not show any distortion product otoacoustic emission threshold change at all frequencies. This finding suggests that a zinc-deficient diet increased the ABR threshold in CBA mice and a zinc-adequate diet restored the ABR threshold to normal.
    Neuroreport 12/2011; 23(4):201-5. · 1.40 Impact Factor
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    ABSTRACT: We report the first case of Susac syndrome in Koreans, in a 23-yr-old female patient who presented with sudden visual loss and associated neurological symptoms. Ophthalmic examination and fluorescein angiography showed multiple areas of branch retinal artery occlusion, which tended to recur in both eyes. Magnetic resonance imaging showed dot-like, diffusion-restricted lesions in the corpus callosum and left fornix, and audiometry showed low-frequency sensory hearing loss, compatible with Susac syndrome. She received immunosuppressive therapy with oral steroid and azathioprine. Three months later all the symptoms disappeared but obstructive vasculitis have been relapsing. This patient demonstrated the entire clinical triad of Susac syndrome, which tends to occur in young females. Although this disorder has rarely been reported in Asian populations, a high index of suspicion is warranted for early diagnosis and timely treatment.
    Journal of Korean medical science 11/2011; 26(11):1518-21. · 0.84 Impact Factor
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    ABSTRACT: Falls are a major problem in the elderly. Age-related degeneration of the human balance system increases the risk of falls. Kyphosis is a common condition of curvature of the upper spine in the elderly and its development occurs through degenerative change. However, relatively little is known about the effect of kyphotic changes on balance in the elderly. The aim of this study is to investigate the influence of kyphosis on the balance strategy through use of the motor control test (MCT) in computerized dynamic posturography. Fifty healthy subjects who were not affected by other medical disorders that could affect gait or balance were enrolled in the study. By simulation of kyphotic condition through change of the angles of the line connecting the shoulder to the hip and the ankle axis by approximately 30°, the latency and amplitude of the MCT were measured in upright and kyphotic condition. In the kyphotic condition, latency was shortened in backward movement. In forward movement, latency was shortened only in large stimulation. The amplitude in forward movement was decreased in kyphotic condition. However, the change of amplitude was not significant in large intensity backward movement in the same condition. Kyphotic condition decreases the latency of MCT, especially in backward movement. These findings imply that kyphotic condition may serve as a protective factor against falls.
    Clinical and Experimental Otorhinolaryngology 09/2011; 4(3):118-21. · 0.88 Impact Factor
  • Joong Ho Ahn, Hyun Woo Lim, Kwang-Sun Lee
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    ABSTRACT: We suggest that cochlear implantation (CI) should be a good therapeutic modality for hearing restoration in patients with common cavity malformed ears. To analyze hearing improvement from CI performed in common cavity malformed cochleae. A total of 11 patients (5 male and 6 female, mean age 4.5 ± 2.8 years) and 12 ears were enrolled in this study. During the insertion of electrodes, we used C-arm fluoroscopy to avoid intrameatal placement. We evaluated hearing improvement every 6 months and the mean follow-up period was 80.5 ± 24.1 months (53-125 months). During the operation, there were only four cases with fully inserted electrodes. Cerebrospinal fluid gushed out in two cases during the cochleostomy and postoperative meningitis occurred in two patients. One patient had to undergo reimplantation 4 years later due to device failure and recurrent meningitis. During the 48 months follow-up hearing evaluation, the ability of hearing increased along with the age. The final average MAIS, CAP, SIR, and open set one- and two-syllable word scores were 90.3 ± 18.1%, 4.9 ± 1.6, 3.1 ± 0.9, 24.1 ± 25.9%, and 48.6 ± 38.7%, respectively.
    Acta oto-laryngologica 05/2011; 131(9):908-13. · 0.98 Impact Factor
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    ABSTRACT: The results suggest that elevated c-Met expression in combination with the co-expression of hepatocyte growth factor (HGF) in the epithelial cells of inverted papilloma may proliferate the epithelial cells of inverted papilloma. HGF and its receptor, c-Met, have been identified in a variety of neoplastic and normal tissue types, implicating these factors in tissue regeneration and tumor progression. We investigated the expression and distribution of HGF and c-Met in normal nasal mucosa and inverted papilloma, to evaluate the possible influence of HGF and c-Met on the development of inverted papilloma. Normal inferior turbinate mucosa and inverted papilloma were examined for expression of HGF and c-Met using RT-PCR, immunohistochemistry and Western blot analysis. Using immunohistochemistry, moderate to high levels of HGF and c-Met protein were localized in epithelial cells in inverted papillomas tested in the present study. In normal turbinate mucosa immunopositive HGF was detected in the submucosal glands where faint staining was found. However, c-Met was noted in the epithelial cells and submucosal glands of normal turbinate mucosa. RT-PCR and Western blot analysis showed that the expression levels of HGF and c-Met were increased in inverted papilloma in comparison with the normal turbinate mucosa.
    Acta Oto-Laryngologica 08/2006; 126(7):724-9. · 1.11 Impact Factor
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    ABSTRACT: Placenta growth factor (PIGF) was originally described as a placenta produced homodimeric protein that shares substantial structural similarity with vascular endothelial growth factor (VEGF) . It is becoming increasingly evident that PIGF may di-rectly or indirectly modulate several key vascular events in various tissues. These include angiogenesis or vasculogenesis, vas -cular maturation and stabilization, vascular permeability, and endothelial cell survival. Inflammatory reaction in the nasal mucosa increases mucosal vascular permeability, resulting in edematous nasal mucosa with polypoid change. In this respect, PIGF may play a role in the formation of nasal polyp. In the present study we evaluated the expression of PIGF mRNA and protein in human inferior turbinate mucosa and nasal polyp. The expression and localization of PlGF mRNA and protein were inves-tigated in the inferior turbinate mucosa and nasal polyps using reverse transcription-polymerase chain reaction (RT-PCR) , Western blotting and immunohistochemistry. These results showed that the mRNA transcripts and protein for PlGF are expres -sed in human turbinate mucosa and nasal polyps. Semiquantitative RT-PCR revealed that PIGF mRNA in nasal polyps increased in its expression level than that in nasal turbinate mucosa. Likewise, immunoblot analysis demonstrated a higher expression of PIGF protein in nasal polyp tissues, compared with that of the nasal turbinate mucosa. However, immunohistochemical findings revealed that PlGF is localized in the endothelial lining of blood vessels in the inferior turbinate mucosa, whereas it is expressed in the epithelial cells of nasal polyps. These results indicate that PlGF mRNA and protein are expressed in normal turbinate mucosa and nasal polyp. Further, based on the fact showing that the expression site of PIGF is different in both tissues, the action mechanism of PIGF may be different in human nasal mucosa and nasal polyp. That is, the PIGF may play a role in the physiolo gical function of normal nasal mucosa, possibly the maintenance of blood vessel and in the pathogenesis of nasal polyp formation. KEY WORDS£ºInferior turbinate mucosa¡¤Nasal polyp¡¤PlGF.

Publication Stats

26 Citations
25.28 Total Impact Points

Institutions

  • 2012
    • Ulsan University Hospital
      Urusan, Ulsan, South Korea
    • Yonsei University Hospital
      Sŏul, Seoul, South Korea
  • 2011
    • The Australian Society of Otolaryngology Head & Neck Surgery
      Evans Head, New South Wales, Australia
    • Gangneung Asan Hospital
      Sŏul, Seoul, South Korea