Increased Resting-State Positron Emission Tomography Activity After Cochlear Implantation in Adult Deafened Cats

Objectives@#. Cochlear implants are widely used for hearing rehabilitation in patients with profound sensorineural hearing loss. However, Cochlear implants have variable results, and central neural plasticity is considered to be a reason for this variability. We hypothesized that resting-state cortical networks play a role in conditions of profound hearing loss and are affected by cochlear implants. To investigate the resting-state neuronal networks after cochlear implantation, we acquired 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) images in experimental animals. @*Methods@#. Eight adult domestic cats were enrolled in this study. The hearing threshold of the animals was within the normal range, as measured by auditory evoked potential. They were divided into control (n=4) and hearing loss (n=4) groups. Hearing loss was induced by co-administration of ethacrynic acid and kanamycin. FDG-PET was performed in a normal hearing state and 4 and 11 months after the deafening procedure. Cochlear implantation was performed in the right ear, and electrical cochlear stimulation was performed for 7 months (from 4 to 11 months after the deafening procedure). PET images were compared between the two groups at the three time points. @*Results@#. Four months after hearing loss, the auditory cortical area’s activity decreased, and activity in the associated visual area increased. After 7 months of cochlear stimulation, the superior marginal gyrus and cingulate gyrus, which are components of the default mode network, showed hypermetabolism. The inferior colliculi showed hypometabolism. @*Conclusion@#. Resting-state cortical activity in the default mode network components was elevated after cochlear stimulation. This suggests that the animals’ awareness level was elevated after hearing restoration by the cochlear implantation.

The Clinical Implications of Simultaneous Bilateral Chronic Ear Surgery for Patients with Asymmetric Hearing / 대한이비인후과학회지

Background and Objectives@#Surgery for bilateral chronic otitis media (COM) is usually performed sequentially, not simultaneously. The main reason is to prevent iatrogenic bilateral conductive hearing loss during recovery period. However, with asymmetric hearing loss, the difference in patient inconvenience between sequential and simultaneous surgery may be the same. This study evaluates the efficacy of simultaneous COM surgery in patients with asymmetric hearing.Subjects Materials and Method From 2012 to 2018, 9 patients underwent simultaneous bilateral COM surgery. The period of patients’ hospital stay, the success rate of tympanoplasty, tolerability for operation, and hearing thresholds were analyzed statistically. @*Results@#For the 8 same-day surgery patients, the mean hospital period was 4.4±0.7 days, which was much shorter than that of sequential surgery (8 days). Tympanoplasty was successful in all patients without complications. In the better side, the preoperative/postoperative mean air conduction thresholds (AC) were 62.97±12.89 dB/47.81±19.07 dB (p=0.017), the bone conduction thresholds (BC) were 46.72±10.31 dB/37.66±16.99 dB (p=0.161) and the air-bone gaps (ABG) were 16.25±8.81 dB/10.16±7.78 dB (p=0.176). In the worse side, the preoperative/ postoperative mean AC were 86.56±18.22 dB/72.18±29.43 dB (p=0.035), BC were 53.28± 11.10 dB/48.13±18.41 dB (p=0.173), and ABG were 33.28±11.22 dB/24.06±14.80 dB (p=0.500). In both ear, the postoperative AC and BC were better than or equivocal to those of the preoperative value, and the result was similar with each of the unilateral ear audiological results. @*Conclusion@#Despite the fact that there is no complete consensus to date, simultaneous bilateral COM surgery can be an option when patients have asymmetric hearing loss. Simultaneous bilateral COM surgery could save time, cost, and lead to similar results with sequential surgery, so it could be a considerable surgical option for patients with bilateral COM.

Incidence Rate and Characteristics of Falls in Patients Using Comprehensive Nursing Care Service / 보건행정학회지

BACKGROUND: Falls are the most frequent adverse events reported in hospitals. The aim of this study was to investigate the incidence rate and characteristics of falls in patients who used comprehensive nursing care service in National Health Insurance Service Ilsan Hospital. METHODS: Incidence rate of falls was investigated in patients using comprehensive nursing care service, from July 2013 to Jun 2017 and compared with those not using this service. The characteristics and risk factors for falls, and fall-related injuries were obtained. RESULTS: Among the 62,445 patients who used the comprehensive nursing care service for 4 years, total of 672 falls were reported. The incidence rate of falls per 1,000 patients-day was 1.15. The percentage of fall-related injuries was 26.9% and that of major injury was 2.2%. Although the incidence rate of all falls was slightly higher in patients using comprehensive nursing care service than those not using this service, falls-related injuries were not correlated with the implementation of this service. CONCLUSION: The falls could be more frequently detected and reported in comprehensive nursing care service, but there was no difference in fall-related injuries.

The Development and Application of Core Fundamental Nursing Skills Improvement Education Program for New Nurses in Comprehensive Nursing Care Ward / 한국간호교육학회지

PURPOSE: The purpose of this study was to investigate the effect of the development and application of the new nurses' core skill program on the clinical skill, confidence, knowledge and performance of new nurses. METHODS: This study was a nonequivalent control group post-test design on 46 new nurses with 3 to 6 months work experience in a general hospital. Data were collected from August 2015 to August 2016. A training program of core fundamental nursing skills was applied on 23 new nurses from 2016 in the experiment group, and an existing training method was applied on 23 new nurses from 2015 in the comparison group. The collected data were analyzed using SPSS/WIN 23.0. RESULTS: The experimental group (89±4.29) showed higher score in practical skill assessment compared to the control group (85.09±3.99) and showed a statistically significant difference (p<001). CONCLUSION: A training program of core fundamental nursing skills for new nurses proved effective in improving practical skills. Further research on the development of a systemic training program that can improve clinical nursing knowledge and work ability for new nurses according to the extended enforcement of a Nursing Care Integrated Service ward is needed.

Clinical Features and Outcomes of a Rare Nasal Cavity Tumor Glomangiopericytoma / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Glomangiopericytoma falls within the category of borderline low-malignant-potential soft tissue tumors of the nose and paranasal sinuses. It is a rare tumor arising from the pericytes surrounding capillaries, and accounts for less than 0.5% of all sinonasal tumors. The aim of this study was to analyze the clinical manifestation and surgical outcomes of the glomangiopericytoma in the nasal cavity. SUBJECTS AND METHOD: Medical records of eight patients who were surgically managed for glomangiopericytoma of the nose and paranasal sinuses from 2000 to 2015 were retrospectively reviewed. Clinical features, size, Immunohistochemical staining, extent of surgery, adjuvant treatment, and recurrence were evaluated. RESULTS: Eight patients, 3 males and 5 females, were enrolled, with the mean age of 54.7 years old. The most common symptom of glomangiopericytoma was ipsilateral nasal obstruction. All patients got surgical treatment, and one patient received radiation to the surgical site, whose margin of resection was positive. The mean follow-up period was 39.5 months (3-176 months). During the follow-up period, one patient was found to have a positive resection margin. CONCLUSION: The surgical outcome shows that complete initial excision is important to prevent recurrence. Furthermore, adjuvant radiation therapy may also be a reasonable option for some patients with margin involvement.

A Spontaneous Pneumatocele Presenting with External Auditory Canal Obstruction / 대한이비인후과학회지

A pneumatocele is an air-filled cavity in the body. In the head and neck areas, the extensive hyperpneumatization of the temporal and occipital bones is typically associated with pneumatocele formation, which results in the spontaneous collection of gas, usually air, beneath the pericranium or within the skull. We herein report a case of stenosis of the external auditory canal caused by a left mastoid pneumatocele in a 12-year-old boy who was successfully treated with left simple mastoidectomy and canaloplasty.

Correction of Prominent Ears / 대한이비인후과학회지

External ear anomaly was not uncommon disease. The spectrum of anomaly is wide, from mild anomalies including prominent ears, cryptotia to absence of external ear. In western countries, prominent ears were common and surgical correction was usually performed in their childhood period. However in Asian countries, including Korea, prominent ears were not considered correcting condition. Many techniques and skills were introduced to perform otoplasty since 19th century. For improving surgical result of otoplasty, operator should choose suitable surgical techniques considering patient's condition in these techniques and can read demands of patients.

Audiologic Patterns of Otic Capsule Preserving Temporal Bone Fracture: Effects of the Affected Subsites

OBJECTIVES: This study was aimed to assess the relationship between the type of temporal bone area involved and conductive hearing loss. METHODS: We enrolled 97 patients who visited the otolaryngology clinics of Seoul National University Hospital or Boramae Medical Center, Seoul Metropolitan Government-Seoul National University with temporal bone fracture between January 2004 and January 2014. Audiometric parameters, including initial and improved air-bone (AB) conduction gap values, were reviewed in accordance with the temporal bone computed tomography (external auditory canal [EAC], middle ear [ME], mastoid [M], and ossicle [O]). RESULTS: Patients with ossicular chain involvement exhibited a larger AB gap compared to those with no ossicular chain involvement at 250, 1,000, 2,000, and 4,000 Hz. Among the groups without ossicular chain involvement, the initial AB gap was largest in patients with EAC+ME+M involvement, followed by the ME+M and M-only involvement groups. The greatest improvement in the AB gap was observed in the EAC+ME+M group followed by the ME+M and M-only groups, irrespective of ossicular chain involvement. Improvements in AB gap values were smallest at 2,000 Hz. CONCLUSION: Conductive hearing loss pattern differed according to the temporal bone area involved. Therefore, areas such as the hematoma and hemotympanum, as well as the fracture line of the temporal bone area, must be evaluated to predict audiologic patterns with otic capsule preserving temporal bone fracture.

Long-term Outcome of Cochlear Implant in Patients with Chronic Otitis Media: One-stage Surgery Is Equivalent to Two-stage Surgery

This study compared long-term speech performance after cochlear implantation (CI) between surgical strategies in patients with chronic otitis media (COM). Thirty patients with available open-set sentence scores measured more than 2 yr postoperatively were included: 17 who received one-stage surgeries (One-stage group), and the other 13 underwent two-stage surgeries (Two-stage group). Preoperative inflammatory status, intraoperative procedures, postoperative outcomes were compared. Among 17 patients in One-stage group, 12 underwent CI accompanied with the eradication of inflammation; CI without eradicating inflammation was performed on 3 patients; 2 underwent CIs via the transcanal approach. Thirteen patients in Two-stage group received the complete eradication of inflammation as first-stage surgery, and CI was performed as second-stage surgery after a mean interval of 8.2 months. Additional control of inflammation was performed in 2 patients at second-stage surgery for cavity problem and cholesteatoma, respectively. There were 2 cases of electrode exposure as postoperative complication in the two-stage group; new electrode arrays were inserted and covered by local flaps. The open-set sentence scores of Two-stage group were not significantly higher than those of One-stage group at 1, 2, 3, and 5 yr postoperatively. Postoperative long-term speech performance is equivalent when either of two surgical strategies is used to treat appropriately selected candidates.

Neurocognitive Outcome in Survivors of Childhood Acute Lymphoblastic Leukemia: Experience at a Tertiary Care Hospital in Korea

This study was conducted to investigate long-term neurocognitive outcomes and to determine associated risk factors in a cohort of Korean survivors of childhood acute lymphoblastic leukemia (ALL). Forty-two survivors of ALL were compared with 42 healthy controls on measures of a neurocognitive test battery. We analysed potential risk factors (cranial irradiation, sex, age at diagnosis, elapsed time from diagnosis, and ALL risk group) on neurocognitive outcomes. ALL patients had lower, but non-significant full-scale intelligence quotient (FSIQ, 107.2 +/- 12.2 vs. 111.7 +/- 10.2), verbal intelligence quotient (VIQ, 107.7 +/- 13.6 vs. 112.2 +/- 11.4), and performance intelligence quotient (PIQ, 106.3 +/- 14.2 vs. 110.1 +/- 10.7) scores than healthy controls. However, patients treated with cranial irradiation performed significantly lower on FSIQ (102.2 +/- 8.1), VIQ (103.3 +/- 11.7), and PIQ (101.4 +/- 13.2) compared to non-irradiated patients and healthy controls. ALL patients also had poor attention, concentration, and executive functions. Among ALL survivors, cranial irradiation was a risk factor for poor FSIQ, being male was a risk factor for poor PIQ, and younger age was a risk factor for poor attention. Therefore, the delayed cognitive effects of ALL treatment and its impact on quality of life require continuing monitoring and management.

Clinical Characteristics of Patients with Major Depressive Disorder That Affect One-Year Rehospitalization Rate: A Retrospective Study in a University Hospital / 대한정신약물학회지

OBJECTIVE: This study was designed to investigate the clinical characteristics of patients with major depressive disorder who were rehospitalized within a year in a naturalistic setting at a university hospital. METHODS: Inpatients with major depressive disorder patients were retrospectively investigated. Data on patients' demographic factors, clinical variables-age, sex, education year, socioeconomic state, marital state, illness duration, length of stay, severity of illness, presence of psychotic features, number of past depressive episodes and hospitalization, family history, comorbidity-were collected. Use of antidepressants, antipsychotics, mood stabilizers and hypnotics were investigated. RESULTS: A total of 238 patients participated in the study. No significant differences were observed between one-year rehospitalized group and the non-rehospitalized group in demographic factors and clinical variables except for the number of previous psychiatric hospitalizations. The mean number of previous psychiatric hospitalization was significantly higher in the one-year rehospitalized group than the non-rehospitalized group (0.41+/-0.83 times vs. 0.23+/-0.83 times) (p=0.048). No significant differences in rehospitalized rates were observed among the disparate treatment types. One-year rehospitalization rate was significantly higher in patients who discontinued antidepressants than the patients who continued the antidepressants (15.9% vs. 0%) (p=0.002). CONCLUSION: The present data suggest that the number of previous psychiatric hospitalizations is higher in patients who were rehospitalized within a year and the discontinuation of antidepressant might be an influencing factor. Further controlled studies are recommended to confirm our findings.

Temporal Processing in the Auditory System / 대한이비인후과학회지

The auditory system recognized sound waves. The sound waves are longitudinal waves in the air, where the pressure varies in time. It is distinguished as the rapid pressure changes, referred to as 'fine structure', and slower overall changes of amplitude fluctuations, as 'envelope'. The auditory system has a limited ability to follow the time-varying envelope, and this ability is known as 'temporal resolution'. Our auditory system analyzes sound waves in frequency, intensity, and time domain. The understanding about frequency and intensity domain is relatively easy compare to time domain. Hearing threshold is measured by sound intensity in frequency domain. However the speech discrimination and understanding of the sentence in quiet and noise are associated with temporal resolution. So for the comprehensive understanding about the auditory system and hearing ability, we must extend our knowledge to the temporal ability of the auditory system.

Correlation between Dose of Ethacrynic Acid and Weight of Cat in the Cat Deafening Procedure / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Co-administration of kanamycin (KM) with the loop diuretic ethacrynic acid (EA) has been known to produce a rapid and profound hearing loss in adult animals. The objective of this study was to see if monitoring the hearing status during intravenous infusion of EA could minimalize individual variability and to evaluate the correlation between the dose of EA and the body weight (wt). MATERIALS AND METHOD: Twenty cats with the mean age of 24 weeks+/-3.7 (range, 20.6-28.3 weeks) and the mean weight of 3.27 kg+/-0.75 (range 2.4-4.75 kg) received a subcutaneous injection of KM (300 mg/kg) followed by an intravenous infusion of EA (1 mg/min). Click evoked auditory brainstem responses (ABRs) were recorded to monitor the hearing during the infusion. When the ABR thresholds rose to levels in excess of 90 dB SPL, the infusion of EA was stopped. The histopathologies for sections of apex, middle, base of cochlea were examined after 6 months. RESULTS: There was a significant positive correlation (p<.001, r2=.583) between the EA dose and body weight. Cochlear histopathology showed an absence of organ of Corti and decrease of spiral ganglion cells in the majority of cochleas, especially in the basal turn. The extent of loss of spiral ganglion cells was dependent on their distance from the round window. CONCLUSION: Monitoring the animal's hearing status during the procedure ensured that the dose of EA was optimized for individual animals. Thus, the positive correlation between the EA dose and body weight should be considered should in designing the animal models of controlled high frequency hearing loss.

Factors Affecting the Extrusion Rate of Ventilation Tubes

OBJECTIVES: The objective of this study was to determine the various factors that affect the extrusion rate of ventilation tubes (VTs), including the nature of the middle ear effusion. METHODS: A retrospective chart review of 82 pediatric patients (177 ears) who received VT insertion surgery under general anesthesia was carried out to evaluate the relationship between various factors and the VT extrusion rate. The factors we analyzed included age, gender, the adenoid size, the amount and content of the middle ear effusion after myringotomy, bleeding events, associated adenoidectomy and the findings of the tympanic membrane status, the tympanometry and the audiometry of the air bone gap. RESULTS: The mean extrusion time was 254 days (range, 11 to 809 days). The patients with no history of previous VT insertion had a longer extrusion time (mean, 279 days) than did the patients who had undergone previous VT insertion (mean, 203 days). The patients with serous effusion had the shortest extrusion time (mean, 190 days) as compared to those patients with glue (273 days) and pus (295 days) effusions. Other factors had no statistical significant relationship with the extrusion time. CONCLUSION: The mean VT extrusion time was 254 days. The VT extrusion time was significantly related to the characteristics of the middle ear effusion and a history of previous VT insertion. Thus, the nature of middle ear effusion can provide a clinical clue to predict the VT extrusion time.

Two Cases of Intracochlear Schwannoma / 대한이비인후과학회지

Intracochlear schwannoma is a rare tumor arising from Schwann cells limited to the cochlea. Most of the cases have been found incidentally at autopsies or during surgeries. Today, gadoliniumenhanced magnetic resonance imaging (MRI) has made the diagnosis possible before surgical intervention. Intracochlear schwannoma presents unilateral progressive hearing loss, tinnitus or vague unsteadiness, all of which are common otologic symptoms seen in the outpatient department. Therefore, a high index of suspicion to detect this tumor is needed. We report two cases of intracochlear schwannoma: one case was diagnosed at gadolinium-enhanced MRI and removed by modified transotic approach preserving external auditory canal; the other case was followed up closely without the intervention of surgery.

Outcome Analysis of Cochlear Implantation in Elderly Patients / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Surgical indications and effect of auditory rehabilitation have not been established in elderly deaf patients who received cochlear implant (CI). The aim of this study is to analyze the outcomes of CI with respect to auditory performance and surgical complication in elderly deaf patients. SUBJECTS AND METHOD: Nineteen postlingually deafened patients who were 60 years and older at the time of implantation were included in the study from April 1992 to October 2006. They were compared to a group of 53 younger patients (<60 years) at the time of implantation. Surgical complications were identified and speech performance was evaluated preoperatively and postoperatively at 1 month, 3 months, 6 months, 1 year and 2 years. RESULTS: In the etiology, progressive hearing loss was most common in both groups. Perioperative complications such as temporary dizziness, wound problem, tinnitus, and temporary facial weakness showed no significant differences between elderly and control groups despite higher incidence of underlying disease in elderly patients. Preoperative speech performance (audiologic K-CID) was significantly better in control group than in elderly group, but there were no significant differences in postoperative period. CONCLUSION: The outcomes of CI in the elderly patients have been comparable with those of younger adults. Advanced age alone could not preclude anyone from being candidates of CI.

Hearing Changes after Stapes Surgery in Otosclerosis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Hearing loss is the main symptom of otosclerosis. Stapes surgery could restore the hearing ability, but the amount of restoration was changed as time passed. The aims of this study were to analyze the outcome of primary stapes surgery in otosclerosis and to compare hearing changes in stapedectomy and stapedotomy group. SUBJECTS AND METHOD: This study involved 221 ears, which were operated on for otosclerosis in Seoul National University Hospital from 1983 to 2005. We analyzed the hearing results of stapes surgery regarding air conduction, bone conduction, air-bone gap using the operation methods in preoperative, postoperative 1, 3, 6, 12, 24 months and after 36-months period. RESULTS: Stapedectomy was performed in 75 ears and stapedotomy in 146 ears. There were no differences of mean age, preoperative hearing between stapedectomy and stapedotomy group. In the postoperative period, hearing thresholds were significantly decreased compared with preoperative period in each group. The stapedectomy group showed more improvement of air conduction and reduction of AB gap than the stapedotomy group. Results of bone conduction showed no difference after the postoperative 12 months period between the two groups. Hearing improvement went on upto postoperative 12 months. Development of sensorineural hearing loss was found in two patients (2.7%) in the stapedectomy group and in one patient (0.68%) in the stapedotomy group. CONCLUSION: Stapedectomy showed better hearing results, but had more risks of sensorineural hearing loss in this study.

A Temporal Bone Study of Insertion Trauma and Intracochlear Position of Straight Type Electrode for Cochlear Implant / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The goal of this study was to examine insertion depth, intracochlear position and insertion trauma with the stimulation electrode of the Nurobiosys cochlear implant. SUBJECTS AND METHOD: Four electrodes were implanted in fresh temporal bones of the human cadavers using realistic surgical procedures. Plain film X-ray images were taken from the electrode inserted in the specimens to estimate the insertion depth. After the electrode implantation, all human temporal bones were trimmed to extract the cochleae. The extracted cochleae from the temporal bone were immersed in acrylic resin to fix the position of electrode placed in the scala tympani. The resin treated cochleae were cut in radial section and polished. All crosssections were imaged with a microscope to assess the trauma by the electrode implantation. RESULTS: The mean insertion depth was about 300degrees with the cochlea angle. The insertion trauma was observed in one section of a temporal bone. The mean distance from electrode to modiolus was about 0.75 millimeter. CONCLUSION: The incidence, severity of trauma and insertion depth of the studied electrode showed similar results with that of other straight type electrode in literature.

The Korean Otorhinolaryngologist's Interest in Facial Plastic and Reconstructive Surgery / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: To assess the interest of Korean otorhinolaryngologists in facial plastic and reconstructive surgery (FPRS). SUBJECTS AND METHOD: We performed a 15-question survey about the experience and interest in FPRS among Korean otorhinolaryngologists. The response rate was 23% (206/899, university and general hospital : 34%, private practice : 14%). RESULTS: In most respondents, the proportion of FPRS in their practice was less than 25%. Rhinoplasty was the most commonly performed procedure among FPRS followed by otoplasty and blepharoplasty. Ninety-four percent of respondents regarded their training in FPRS as insufficient and 38% had taken supplementary courses for the FPRS. Forty percent responded that FPRS should be taught during and after residency training. Finally, 89% of all respondents responded that FPRS should be part of the field of otorhinolaryngology, and 71% responded that it should become a subspecialty under the Korean otorhinolaryngologic society. CONCLUSION: There is an interest in integrating FPRS training into the Korean otorhinolaryngology residency training program.

Treatment Result of Mastoidectomy in Pediatric Chronic Suppurative Otitis Media / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Chronic suppurative otitis media (CSOM) is a common infectious disease in childhood of poor hygiene group. In addition, in industrialized countries, with rising popularity of tympanostomy tubes for management of otitis media with effusion, CSOM is a potential problem in any child who had inserted ventilating tubes previously. Hearing loss following CSOM can negatively affect learning, speech, and cognitive function, so effective and timely management of CSOM is mandatory. The surgical procedure may be necessary in some children with CSOM, but when it is performed at a too early age, there might be more chances of recurrence than adults. SUBJECTS AND METHOD: Used in the study were 51 ears from patients who received tympanomastoidectomy due to CSOM in tertiary referral center from 1995 through 2004. The mean age was 9 years and 6 months. Cholesteatoma was found in 30 cases (58.8%). Age at operation, hearing outcomes, and the surgical results were retrospectively reviewed. RESULTS: Canal wall down mastoidectomy was performed in 23 cases and canal wall up procedure in 28 cases. Revision surgery was performed in 9 cases (17.6%) and mean duration between first and revision surgery was 27 months. In the cases of cholesteatoma, the rate of revision surgery was different between under 6 years old and over 7 years old group (p=.045). The age at 1st operation and postoperative hearing outcome had no correlation. CONCLUSION: Since the1st operation is performed earlier, the rate of revision may increase, especially in cases of cholesteatoma.