Hearing Threshold of Korean Adolescents Associated with the Use of Personal Music Players

PURPOSE: Hearing loss can lead to a number of disabilities and can reduce quality of life. Noise-induced hearing losses have become more common among adolescents due to increased exposure to personal music players. We, therefore, investigated the use of personal music player among Korean adolescents and the relationship between hearing threshold and usage pattern of portable music players. MATERIALS AND METHODS: A total of 490 adolescents were interviewed personally regarding their use of portable music players, including the time and type of player and the type of headphone used. Pure tone audiometry was performed in each subject. RESULTS: Of the 490 subjects, 462 (94.3%) used personal music players and most of them have used the personal music player for 1-3 hours per day during 1-3 years. The most common type of portable music player was the MP3 player, and the most common type of headphone was the earphone (insert type). Significant elevations of hearing threshold were observed in males, in adolescents who had used portable music players for over 5 years, for those over 15 years in cumulative period and in those who had used earphones. CONCLUSION: Portable music players can have a deleterious effect on hearing threshold in adolescents. To preserve hearing, adolescents should avoid using portable music players for long periods of time and should avoid using earphones.

Platelet Aggregability in the Patients with Peripheral Vestibulopathy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Circulatory disturbance to vestibular organ has been regarded as one of the causes that bring about vertigo, and alteration of the platelet function is known to be an important factor inducing circulatory deficit. This study was designed to evaluate platelet aggregability in the patients with peripheral vestibulopathy, and to evaluate difference according to duration of illness. MATERIALS AND METHODS: Platelet aggregation tests to adenosine diphosphate (ADP), ristocetin, epinephrine and collagen were performed in 10 normal subjects and 15 patients with peripheral vestibulopathy. Maximum aggregation rates from aggregation curves were compared between the two groups, and also between the two groups of patients who had different duration of illness. RESULTS: In the patient group, platelet aggregations to ADP, ristocetin and collagen were increased compared to normal subjects and significant differences were found in aggregations to ADP and ristocetin. However, there was no significant difference according to different duration of illness in the patient group. CONCLUSION: These results suggest that platelet aggregability is increased in the patients with peripheral vestibulopathy, and duration of illness does not affect platelet aggregability.

Differences of Nasal Hypersensitivity between Smokers and Nonsmokers / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Smoking is regarded as one of the factors that bring about nonspecific hypersensitivity in allergic nasal mucosa. But it is uncertain how chronic smoking affects hypersensitivity in nasal mucosa. This study was designed to evaluate the relationship between smoking and nasal hypersensitivity. In this study, histamine is used since it is commonly used to evaluate nasal hypersensitivity. MATERIAL AND METHODS: Twelve smokers and 9 nonsmokers were participated in this study. Nasal mucosae of each subjects were stimulated by thiorphan followed by substance P. After stimulation, several dilutions of 10 to 5X104 ng/ml of histamine was instilled to both nasal cavity at intervals of 10 minutes. We measured the volume of nasal cavity by acoustic rhinometry in each step and counted the number of sneezing and nasal blowing at every 10 minute intervals. Changes in volume after each dillutions of histamine instillations were compared with the values measured after the stimulation by thiorphan and substance P., and this value was expressed as the percentage volume change. RESULTS: The nasal volume of smoker group was increased upto 100 ng/ml of histamine and decreased from 1000 ng/ml of histamine. The nasal volume of nonsmoker group decreased more than the smoker group with each dilution of histamine. The number of sneezing and nasal blowing increased in each group with each dilution of histamine. CONCLUSIONS: Chronic smoking may decrease susceptibility of hypersensitivity to histamine in nasal mucosa.

Expression of Phospholipase C-beta1 and Phospholipase C-gamma1 on Cholesteatoma / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: A histological finding that is the most characteristic of cholesteatoma is the proliferation of the squamous cell. Signal transduction through phospholipase C(PLC) participates in the regulation of epidermal cell growth and differentiation. EGF, PDGF, and TGF-alpha bind to their receptors and thereby induce tyrosine phosphorylation of the phospholipase C-gamma1 (PLC-gamma1). PLC-gamma1 is a substrate for several receptor tyrosine kinases and its catalytic activity is increased by tyrosine phosphorylation. Tyrosine kinase phosphorylation of PLC-gamma1 stimulates PLC activation and cell proliferation. The G-protein has been shown to specifically activate PLC-beta1. However, the signal transduction pathway and the significance of PLC in cholesteatoma is unknown. This study attempted to provide some evidence that PLC plays a role in cholesteatoma by investigating the distribution and quantity of PLC-beta1 and PLC-gamma1 in the posterior auricular skin and cholestsatoma. MATERIALS AND METHODS: Western blotting and immunohistochemical study were performed for 20 cholesteatoma specimens obtained from patients who underwent operation. RESULTS: Western blot analyses revealed that PLC-beta1 protein and PLC-gamma1 protein were detectable in cholesteatoma and that these proteins were in higher levels compared with the control. In the imm-unohistochemical study, PLC-gamma1 was detected in the horny cell layer of posterior auricular skin but not in the suprabasal layer and the horny cell layer of cholesteatoma. PLC-beta1 was detected in the primary basal layer and a minor reaction was also noted in the spinous layer of posterior auricular skin. However, there were detactable reactions in both the basal and the suprabasal layers of cholesteatoma. CONCLUSION: The results of this study suggest that there are signal transduction pathways through PLC, over-expression of PLC, the different signaling mechanism by PLC in the basal and the suprabasal layer of cholesteatoma.

Orbital Decompression in Dysthyroid Ophthalmopathy Using Combined Transantral and Transnasal Endoscopic Approach / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Dysthyroid ophthalmopathy is consider to be an autoimmune disorder and the disease is permanent in about 70% of the patients. Endoscopic intranasal approach for the decompression has been described by Kennedy in 1990. However a limitation of the approach is that decompression of the orbital floor lateral to the infraorbital nerve is not possible. So we modified caldwell- Luc's approach combined intranasal decompression by endoscopy. MATERIALS AND METHODS: We performed the orbital decompressions in 5 cases with the exophthalmos. When the inferior bony wall was removed, medial and lateral to the inferior orbital nerve were removed separately and bony ridge was created to protect the nerve. Upper one-third of the lateral wall was penetrated to make an space for herniation of orbital content in case of severe exphthalmos. RESULT: All of the cases were satisfied with the surgery and there has been no evidence of the recurrence so far. CONCLUSION: These combined techniques produce satisfactory results, especially in severe cases.

Alport's Syndrome-A Case Report- / 대한이비인후과학회지

Alport's syndrome is a genetic disorder of basement membranes manifested by a progressive nephropathy and sensorineural hearing loss and ocular lesions. Type 4 collagen, main component of basement membranes, is composed of six genetically distinct chains. Mutation of gene COL4A5 which encodes the 5 chain of type IV collagen may prevent the normal incorporation of 3 and 4 into basement membranes. Main clinical features of this syndrome are hematuria, sensorineural hearing loss, ocular abnormalities including lenticonus and cataract. The characteristics of audiological manifestations are bilateral moderate sensorineural hearing loss with recruitment phenomenon and normal latencies of waves in brain stem evoked response audiometry. We recently experienced a case of Alport's syndrome in 10 year old male patient with sensori-neural hearing loss and esophageal achalasia. We report this case with review of literatures.