A Case of Auricular Schwannoma After Trauma / 대한이비인후과학회지

Schwannoma is a slowly-growing, benign tumor that originates from the Schwann cell and is rarely found in the auricle. In this article, we describe a 20-year-old male patient with an approximately 2 cm auricular mass located in the antitragus of the left ear. The mass was slowlygrowing following an auricular trauma. The mass was completely removed by local excision and the histopathologic review confirmed the diagnosis as an auricular schwannoma. Characteristic immunohistochemical findings may be helpful in differential diagnosis of other tumors. Herein, we present with a literature review a rare case of auricular schwannoma following a trauma.

Sensorineural Hearing Loss of Suspected Autoimmune Etiology: Two Cases of Cogan’s Syndrome / 대한이비인후과학회지

Cogan’s syndrome is a rare inflammatory disease characterized by non-syphilitic keratitis and vestibulo-auditory symptoms including hearing loss, tinnitus, and vertigo. Although its precise pathogenesis is not known, Cogan’s syndrome is generally considered an autoimmune disease. This hypothesis is supported by the frequently successful remission of hearing loss after steroid administration and the association with other autoimmune disorders such as rheumatoid arthritis. Medical treatment of Cogan’s syndrome depends on disease severity and on how extensive the disease is. The involvement of inner ear pathology requires systemic corticosteroid therapy. In cases of treatment failure or the need for a corticosteroid-sparing effect, other immunosuppressive drugs can be used. We experienced two patients with typical Cogan’s syndrome, presenting bilateral progressive sensorineural hearing loss and dizziness with ocular involvement, which we have successfully treated with systemic steroid administration and immunosuppressive therapy.

Case Series Outcomes of Cochlear Implantation in Children with Noonan Syndrome / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Hearing loss is a common complication associated with Noonan syndrome (NS), and the level of hearing loss for NS patients with sensorineural loss ranged from normal to severe. Additional insights into the outcome of cochlear implantation (CI)in children with NS with or without comorbidities are needed. SUBJECTS AND METHOD: In this study, five patients with NS, four with a mutation in PTPN11 and one who tested negative in mutation screening, diagnosed with the clinical scoring systemand underwent CI at ages ranging from 16 to 50 months were retrospectively reviewed. Patientswere evaluated for auditory perception (Categories of Auditory Performance), speech production (Korean Version of the Ling's Stage), and language ability (Receptive and Expressive Vocabulary Test). RESULTS: In five of the children with NS, CI was performed without any complications. Threepatients who received CI before 30 months of age showed outstanding outcomes. One patientwho received CI at 50 months showed limited benefit. One patient who was diagnosed with developmental delay and cochlear nerve hypoplasia underwent CI at 28 months with poor outcome. DISCUSSION: Our report suggests that although the benefit may be influenced by comorbidities associated with NS or delay in hearing rehabilitation, profound hearing loss in patientswith NS may be restored to normal levels in terms of auditory/speech perception and vocabulary/language development. The variable hearing outcomes also underscore the need for earlyscreening and detection of profound hearing loss, and regular follow-up for hearing evaluationin patients with NS.

Case Series Outcomes of Cochlear Implantation in Children with Noonan Syndrome / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES@#Hearing loss is a common complication associated with Noonan syndrome (NS), and the level of hearing loss for NS patients with sensorineural loss ranged from normal to severe. Additional insights into the outcome of cochlear implantation (CI)in children with NS with or without comorbidities are needed.SUBJECTS AND METHOD: In this study, five patients with NS, four with a mutation in PTPN11 and one who tested negative in mutation screening, diagnosed with the clinical scoring systemand underwent CI at ages ranging from 16 to 50 months were retrospectively reviewed. Patientswere evaluated for auditory perception (Categories of Auditory Performance), speech production (Korean Version of the Ling's Stage), and language ability (Receptive and Expressive Vocabulary Test).@*RESULTS@#In five of the children with NS, CI was performed without any complications. Threepatients who received CI before 30 months of age showed outstanding outcomes. One patientwho received CI at 50 months showed limited benefit. One patient who was diagnosed with developmental delay and cochlear nerve hypoplasia underwent CI at 28 months with poor outcome.DISCUSSION: Our report suggests that although the benefit may be influenced by comorbidities associated with NS or delay in hearing rehabilitation, profound hearing loss in patientswith NS may be restored to normal levels in terms of auditory/speech perception and vocabulary/language development. The variable hearing outcomes also underscore the need for earlyscreening and detection of profound hearing loss, and regular follow-up for hearing evaluationin patients with NS.

Comparison of Clinical Usefulness of Program-Assisted and Real Ear Measurement-Assisted Hearing Aids Fitting / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The main objectives of this study were to determine the clinical usefulness of the program-assisted and real ear measurement (REM)-assisted fitting of hearing aids. SUBJECTS AND METHOD: Fifteen participants with moderate to moderately severe hearing loss were enrolled in this study. Objective and subjective fitting results were assessed to compare the benefits between the program-assisted fitting (using a software fitting program) and the REM-assisted fitting. Real ear insertion gain (REIG), sound-field audiometry using warble tone, and Korean Hearing in Noise Test (K-HINT) were performed as objective tests. Sound quality rating was performed as a subjective test. RESULTS: In the program fitting, 48.89% of fitting points failed to come within ±10 dB of the REIG target. In the REM fitting, however, the percentage of failure significantly decreased to 23.33% (p=0.013). In K-HINT test, the reception threshold for speech in quiet situation significantly decreased from 50.1 dB HL with the program fitting to 44.7 dB HL after the REM fitting (p < 0.001). In front noise condition, signal-to-noise ratio improved from 4.53 dB to 3.50 dB with the REM fitting without statistical significance (p=0.099). In the sound quality rating, the REM fitting (4.27±0.56) showed a significantly better sound quality ratings than the program fitting (3.69±0.74) (p=0.017). CONCLUSION: The REM fitting showed better results in both subjective and objective measurements than the program fitting.

Definition and Clinical Implication of Temporal Fine Structure / 대한이비인후과학회지

Perception of sound is associated with the use of multiple acoustic cues in the human auditory system. These acoustic cues can be classified by their temporal and spectral properties. Temporal information can be considered as a slowly varying envelope (ENV) superimposed on a more rapid temporal fine structure (TFS). Various sound-processing techniques have been developed to assess the role of acoustic information carried by temporal ENV and TFS information. Previous studies demonstrated that ENV cues are associated with speech recognition in quiet, while TFS cues have a role to melody/pitch perception and listening to speech in a competing background noise. Besides, a number of studies have shown that the relative insensitivity of hearing-impaired subjects to TFS information. Although current technologies used in cochlear implants are not efficient in delivering the TFS cues, new speech processing strategies have been proposed to deliver TFS information. We herein review the cutting edge of TFS related studies and discuss the clinical implication of TFS.

Definition and Clinical Implication of Temporal Fine Structure / 대한이비인후과학회지

Perception of sound is associated with the use of multiple acoustic cues in the human auditory system. These acoustic cues can be classified by their temporal and spectral properties. Temporal information can be considered as a slowly varying envelope (ENV) superimposed on a more rapid temporal fine structure (TFS). Various sound-processing techniques have been developed to assess the role of acoustic information carried by temporal ENV and TFS information. Previous studies demonstrated that ENV cues are associated with speech recognition in quiet, while TFS cues have a role to melody/pitch perception and listening to speech in a competing background noise. Besides, a number of studies have shown that the relative insensitivity of hearing-impaired subjects to TFS information. Although current technologies used in cochlear implants are not efficient in delivering the TFS cues, new speech processing strategies have been proposed to deliver TFS information. We herein review the cutting edge of TFS related studies and discuss the clinical implication of TFS.

Cochlear Implantation for Profound Hearing Loss After Multimodal Treatment for Neuroblastoma in Children

OBJECTIVES: Neuroblastoma (NBL) predominantly affects children under 5 years of age. Through multimodal therapy, including chemotherapy, radiotherapy, surgery, and peripheral blood stem cell transplantation, the survival rate in patients with NBL have improved while treatment-related complications have also increased. Treatment-related ototoxicity, mainly from cisplatin, can result in profound hearing loss requiring cochlear implantation (CI). We analyzed the effectiveness and hearing preservation of CI recipients who had treated with multimodal therapy due to NBL. METHODS: Patients who received multimodal therapy for NBL and subsequent CIs were enrolled. A detailed review of the perioperative hearing test, speech evaluation, and posttreatment complications was conducted. Speech performance was analyzed using the category of auditory performance (CAP) score and the postoperative hearing preservation of low frequencies was also compared. Patients who were candidates for electro-acoustic stimulation (EAS) used an EAS electrode for low frequency hearing preservation. RESULTS: Three patients were identified and all patients showed improvement of speech performance after CI. The average of CAP score improved from 4.3 preoperatively to 5.8 at 1 year postoperatively. Two patients who were fitted with the Flex electrode showed complete hearing preservation and the preserved hearing was maintained over 1 year. The one remaining patient was given the standard CI-512 electrode and showed partial hearing preservation. CONCLUSION: Patients with profound hearing loss resulting from NBL multimodal therapy can be good candidates for CI, especially for EAS. A soft surgical technique as well as a specifically designed electrode should be applied to this specific population during the CI operation in order to preserve residual hearing and achieve better outcomes.

Evaluation of Satisfaction with Hearing Aids Using a Questionnaire Based on MarkeTrak Survey / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: MarkeTrak survey is a subjective evaluation method for hearing aid users. This investigation evaluated the level of subjective satisfaction in hearing aid users by adopting the MarkeTrak survey method. SUBJECTS AND METHOD: Ninety-seven subjects participated in this study and replied to the Korean version of 8th MarkeTrak survey. The satisfaction score regarding hearing aids used a 7-point scale to analyze the patient-related as well as hearing aids-related factors. RESULTS: Overall satisfaction rate was 60.8%. Among the patient-related factors, women showed significantly higher satisfaction rate (p<0.05) than men but the level of education affected the satisfaction rate (p<0.05). Hearing aids users showed significantly higher satisfaction rate in small group communication than in other circumstances (p<0.05). The factors related to the hearing aids did not have significant influence on the satisfaction rating. CONCLUSION: MarkeTrak survey is a useful questionnaire for evaluating satisfaction about not only hearing factors but also sociodemographic factors and hearing-aids related factors.

Early Neck Exercises to Reduce Post-Thyroidectomy Syndrome after Uncomplicated Thyroid Surgery: A Prospective Randomized Study / 대한갑상선학회지

BACKGROUND AND OBJECTIVES: To evaluate the efficacy and safety of early neck exercises to reduce post-thyroidectomy symptoms and syndromes for patients undergoing thyroid surgery. MATERIALS AND METHODS: One hundred patients who had undergone thyroid surgery were randomly assigned 1:1 to control (delayed exercise, initiating at postoperative 2 weeks) or early exercise group (initiating at postoperative 1 day). Questionnaire survey (voice, globus sense, neck discomfort, swallowing difficulty) and objective measurement (surgical wound adhesion, range of neck motion and scar scale) were performed at 2 weeks and 3 months postoperatively. RESULTS: Compared to control, early exercise significantly decreased the degree of neck discomfort at 2 weeks after thyroid surgery (p=0.037) while other subjective symptoms including voice change, globus sense, and swallowing difficulty were not significantly different between the two groups. The degree of surgical wound adhesion was significantly decreased (p<0.001) and the range of motion was improved in early exercise group (p=0.010). In addition, the objective scores of Vancouver Scar Scale (VSS) were decreased in early exercise group compared to those of control group (p=0.020). CONCLUSION: Early neck exercises are safe and effective to reduce postoperative neck discomfort, wound adhesion, or hypertrophy of scar and to improve the range of motion in patients undergoing thyroid surgery.

Persistent Direction-Fixed Nystagmus Following Canalith Repositioning Maneuver for Horizontal Canal BPPV: A Case of Canalith Jam

The authors report a 64-year-old man who developed persistent direction fixed nystagmus after a canalith repositioning maneuver for horizontal canal benign paroxysmal positional vertigo (HC-BPPV). The patient was initially diagnosed with right HC-BPPV given that the Dix-Hallpike test showed geotropic horizontal nystagmus that was more pronounced on the right side, although the roll test did not show any positional nystagmus. The patient was treated with a canalith repositioning maneuver (Lempert maneuver). The next day, the patient experienced a different character of dizziness, and left-beating spontaneous nystagmus regardless of head position was observed. After a forced prolonged left decubitus and frequent head shaking, his symptoms and nystagmus resolved. This condition, referred to as canalith jam, can be a complication after the repositioning maneuver in patients with BPPV. Atypical positional tests suggest that abnormal canal anatomy could be the underlying cause of canalith jam.

Two Cases of Middle Ear Implantation: Incus Vibroplasty / 대한이비인후과학회지

The Vibrant Soundbridge (VSB) middle ear implant is an alternative rehabilitation option for sensorineural, conductive, and mixed hearing loss. The mechanism of VSB implantation is direct-drive stimulation of the inner ear through a floating mass transducer placed on the ossicular chain. We report our experience of VSB incus vibroplasty, which were successfully performed in two cases without complications and resulted in good functional gain and improve-ment of speech discrimination.

Evaluation of Lymph Nodes in Patients with Concurrent Papillary Thyroid Carcinoma and Cervical Tuberculous Lymphadenitis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: To determine the diagnostic clues to differentiate tuberculous lymph node infection from nodal metastasis in patients with both papillary thyroid carcinoma and cervical tuberculous lymphadenitis. SUBJECTS AND METHOD: We retrospectively reviewed 11 patients suffering concurrently from papillary thyroid carcinomas with cervical tuberculous lymphadenitis. Nine of the 11 patients underwent preoperative neck ultrasonography (US) and seven CT scans. Using the surgical pathology as the reference standards, the results of the preoperative diagnostic tools were re-evaluated according to lymph node level-based analysis. US and CT features were also compared between metastatic nodes and tuberculous lymphadenitis. RESULTS: Preoperative CT could localize the involved lymph node levels and differentiate tuberculous infection from metastasis of thyroid carcinoma in only two of seven patients. The site of the involved lymph nodes, the presence of pulmonary tuberculosis, and the tumor volume of the thyroid carcinoma were the clues to diagnose the lymph node status. However, in five of seven cases, CT could not differentiate tuberculosis from metastasis in the lymph nodes. The morphological characteristics of lymph nodes seen on CT and US did not differ between tuberculous infection and metastasis of papillary thyroid carcinomas. CONCLUSION: Pre-operative CT or US does not provide differential information about lymph node status between tuberculous infection and metastasis in patients with concurrent papillary thyroid carcinomas and cervical tuberculous lymphadenitis. Rather, clinical characteristics such as the site of the involved lymph nodes, the primary tumor burden, and the associated clinical features can help the physician differentiate between them.

Quality Control of Residual Solvents in 18FFDG Preparations by Gas Chromatography / 핵의학분자영상

PURPOSE: Analysis of volatile organic solvents in 2-deoxy-2-[18F] fluoro-D-glucose ([18F]FDG) preparations was performed by gas chromatography (GC), in accordance with USP. MATERIALS AND METHODS: Analyses were carried out on a Hewlett-Packard 6890 gas chromatography equipped with an FID. RESULTS: We determined the amounts of ethanol and acetonitrile on every batch of our routine [18F]FDG preparations, ranging between 5000 ppm and 100 ppm. In our routine preparation of [18F]FDG, the amount of acetonitrile and ethanol in the final product were well below the maximum allowable limit described in the USP. CONCLUSION: Our [18F]FDG preparations were in accordance with the suggested USP maximum allowable levels of the quality control analysis of volatile organic compounds.

Development of Dual Reporter System of Mutant Dopamine 2 Receptor (D2R) and Sodium Iodide Symporter (NIS) Transgenes / 대한핵의학회잡지

PURPOSE: Both human NIS and mutant D2R transgenes are proposed as reporting system in transplanted cell tracking. Using hepatoma cell lines, we constructed a dual reporter system containing human sodium-iodide symporter (hNIS) and dopamine 2 receptor (D2R) and compared its characteristics. MATERIALS AND METHODS: The recombinant plasmid (pIRES-hNIS/D2R) was constructed with IRES (internal ribosome entry site) under control of the CMV promoter. pIRES-hNIS/D2R was transfected to human hepatoma SK-Hep1 cell line with lipofectamine. HEP-ND (SK-Hep1-hNIS/D2R) cells stably expressing hNIS and D2R was established by selection with G418 for two weeks. RT-PCR was performed to investigate the expression of both hNIS and D2R genes. The expressions of hNIS and D2R were measured by 125I uptake assays and receptor binding assays. Specific binding of D2R to [3H]spiperone was verified by Scatchard plot with (+) butaclamol as a specific inhibitor. K (d) and B (max) values were estimated. The correlation between hNIS and D2R expression was compared by using each clone. RESULTS: Similar quantities of hNIS and D2R genes were expressed on HEP-ND as RT-PCR assays. HEP-ND cells showed 30 to 40 fold higher radioiodine uptakes than those of parental SK-Hep1 cells. 125I uptake in HEP-ND cells was completely inhibited by KClO4, a NIS inhibitor. Specific binding to HEP-ND cells was saturable and the K (d) and B (max) values for HEP-ND cells were 2.92 nM, 745.25 fmol/mg protein and 2.91nM, 1323 fmole/mg protein in two clones, respectively. The radioiodine uptake by hNIS activity and D2R binding was highly correlated. CONCLUSION: We developed a dual positron and gamma imaging reporter system of hNIS and D2R in a stably transfected cell line. We expect that D2R and hNIS genes can complement mutually as a nuclear reporting system or that D2R can be used as reporter gene when hNIS gene were used as a treatment gene.

Stability of 188Re Labeled Antibody for Radioimmunotherapy and the Effect of Stabilizing Agents / 대한핵의학회잡지

No abstract available.

New Synthesis of Sestamibi and Comparison of Stability of Its Formulation / 대한핵의학회잡지

No abstract available.

Synthesis of d- and l-Form of 99mTc-HMPAO, and Comparison of Brain Uptake / 대한핵의학회잡지

PURPOSE: 99mTc-HMPAO is a radiopharmaceutical for imaging cerebral blood flow. HMPAO (RR, SS)-4,8- diaza-3,6,6,9-tetramethylundecan-2,10- dione bisoxime) has three stereoismers such as, meso-, d-, and l-HMPAO. Techentium complexes of meso-HMPAO and d,l-HMPAO are known to have different in vivo brain uptakes. In this study, enantiomers of HMPAO (d-HMPAO and l-HMPAO) were separated from d,l-HMPAO. These enantiomers were labeled with 99mTc and the biodistribution studies were performed in mice. MATERIALS AND METHODS: An intermediate imine product was produced from 2,3-butanedione monooxime and 2,2-dimethyl- 1,3-propanediamine (54% yield) and was reduced into a mixture of three isomers (35% yield). The meso-isomer was separated from d,l-mixture by repeated fractional crystallization (11% yield). The d- and l-enantiomers were subsequently separated by co-crystallization with optical isomers of tartaric acid (25% and 5% yield, respectively). Each enantiomeric HMPAO was labeled with 99mTc by reacting with SnCl2 2H2O and 99mTc-pertechnetate. Biodistribution study was performed 1 hr after tail vein injection to ICR mice. RESULTS: Radiochemical purities of each compound were over 80%. In biodistribution study, the brain uptakes of d,l- d- and l-form were 1.34, 1.12 and 1.67% ID/g, respectively. In case of l-Isomer the brain uptake was higher (1.5 fold) than d-isomer. CONCLUSION: We successfully purified each enantiomeric HMPAO. In biodistribution study of stereoismers of 99mTc-HMPAO in mice, l-HMPAO may show better brain image than d,l-HMPAO which was supplied in a commercial kit.

Effect of Carrier on Labeling and Biodistribution of Re-188-Hydroxyethylidene diphosphonate / 대한핵의학회잡지

PURPOSE: Re-188-Hydroxyethylidene diphosphonate (HEDP) is a new cost-effective agent for systemic radioisotope therapy of metastatic bone pain. We investigated the influence of carrier for labeling and biodistribution of Re-188-HEDP using HEDP kit with or without carrier (KReO4). MATERALS AND METHODS: The kits (HEDP 15 mg, gentisic acid 4 mg and SnCl2.2H2O 4.5 mg) with or without carrier (KReO4 0.1 mg) were labeled with Re-188 solution, made available from an in-house generator by boiling for 15 min. We compared the labeling efficiency and stability of carrier-added and carrier-free preparations of Re-188-HEDP. Biodistribution and imaging studies of each preparation were performed in ICR mice (1.85~3.7 MBq/0.1 ml) and SD rats (74.1~85.2 MBq/0.5 ml). RESULTS: The carrier-added preparation showed high labeling efficiency (95% at pH 5) and high stability in serum (88%, 3 hr). However, the carrier-free preparation showed low labeling efficiency (59% at pH 5) and low stability (43%, 3 hr). The carrier-added preparation showed high uptake in bone and low uptake in stomach and kidneys. However, the carrier-free preparation showed lower uptake in bone and higher uptake in both stomach and kidneys, which is supposed to be due to released perrhenate. The carrier-added preparation also showed better images with higher skeletal accumulation, lower uptake in other organs and lower soft tissue uptake than the carrier-free preparation. CONCLUSION: The results of these studies clearly demonstrate that addition of carrier perrhenate is required for high labeling efficiency, stability, bone uptake and good image quality of Re-188-HEDP.

Synthesis and Biodistribution of Flumazenil Derivative F-18(3-(2-Fluoro) flumazenil for Imaging Benzodiazepine Receptor / 대한핵의학회잡지

PURPOSE: Radiotracers that bind to the central benzodiazepine receptor are useful for the investigation of various neurological and psychiatric diseases. [C-11]Flumazenil, a benzodiazepine antagonist, is the most widely used radioligand for central benzodiazepine receptor imaging by PET. We synthesized 3-(2-[F- 18]fluoro)flumazenil, a new fluorine-18 (t1/2=110 min) labeled analogue of benzodiazepine receptor imaging agent, and evaluated in vivo for biodistribution in mice. MATERIALS AND METHODS: Flumazenil (Ro 15-1788) was synthesized by a modification of the reported method. Precursor of 3-(2-[F-18]fluoro)flumazenil, the tosylated flumazenil derivative was prepared by the tosylation of the ethyl ester by ditosylethane. [F-18] labeling of tosyl substitued flumazenil precursor was performed by adding F-18 ion at 85 degree C in the hot cell for 20 min. The reaction mixture was trapped by C18 cartridge, washed with 10% ethanol, and eluted by 40% ethanol. Bidistribution in mice was determined after intravenous injection. RESULTS: The total chemical yield of tosylated flumazenil derivative was ~40%. The efficiency of labeling 3-(2-[F-18]fluoro)flumazenil was 66% with a total synthesis time of 50 min. Brain uptakes of 3-(2-[F-18]fluoro)flumazenil at 10, 30, 60 min after injection, were 2.5+/-0.37, 2.2+/-0.26, 2.1+/-0.11 and blood activities were 3.7+/-0.43, 3.3+/-0.07, 3.3+/-0.09%ID/g, respectively. CONCLUSION: We synthesized a tosylated flumazenil derivative which was successfully labeled with no-carrier-added F-18 by nucleophilic substitution.