BACKGROUND AND OBJECTIVES: At the beginning of the Dix-Hallpike maneuver, one of the two functional pair planes of the vertical canals is presumed to lie in the sagittal plane. However, this presumption is not correct. This paper aims to describe this problem more clearly and speculate on clinical implications. Mathematical and theoretical reasoning will be discussed. MATERIALS AND METHODS: Two sets, each composed of three perpendicular planes, were modeled for simplified semicircular canals in the anatomical position with a 3D modeler. After a yaw rotation of 45 degrees, the surface normal of the vertical canal plane is compared with that of the true sagittal plane. RESULTS: The angle between the two normals was approximately 21.1 degrees. The theoretical vertical canal plane did not lie in the sagittal plane at the beginning position of Dix-Hallpike maneuver. CONCLUSIONS: More exact Dix-Hallpike maneuvers may require a roll tilting about 20 degrees toward the affected side.
Semicircular Canals ; Vertigo

Examination is indispensable to medical education. It qualifies medical education, drives medical students to study hard, and provides guides for the students acquiring a large amount of medical knowledge. This study provides an approach to organize the question pool for medical examination. In this approach, many questions in the form of HTML based texts were stored and managed in text-and memo-type field of Microsoft Access database system. They could be retrieved from the database in computer-generated HTML file, which could be read in word processors and web browsers. Several advantages of HTML bases text were emphasized. Though they are essentially text format data which can be stored and processed easily in text-type field of databases, they don't lose character attributes such as bold, italic, underlined, superscript, subscript and so on. Also they can provide table facility and links to external graphic files. This approach can be applied in other medical information retrieval system.
Education, Medical ; Humans ; Information Systems ; Students, Medical ; Web Browser

No abstract available.
Forearm*

BACKGROUND AND OBJECTIVES: In caloric test, the CP (canal paresis) value was derived from Jongkees formula. The input parameters of the formula were initially nystagmus duration (seconds), which were replaced later with more stable parameters : slow component velocity (SCV, deg/sec). The nystagmus duration cannot be negative value, but SCV can be, especially in acute vestibular loss with excessive spontaneous nystagmus (SN) which is not overcome by caloric nystagmus. This study aims to investigate the occurrence of negative SCV, to check proper processing of negative SCV values in nystagmography software, and to consider the mathematical significance of CP and negative SCV values. MATERIALS AND METHOD: Tests with negative SCV values were examined in 690 alternate binaural bithermal caloric tests (open loop system). RESULTS: Nine percents (62 of 690 tests) showed negative SCV values. The reported CP was erroneously calculated from debased zero SCV values instead of negative SCV values. The underestimated CP (mean 52.1%, SD 21.8%) can be corrected (mean 80.9%, SD 21.8%) by recalculations with negative SCV values. CONCLUSION: To produce correct CP values in caloric tests, negative values should be properly processed about the SCV value of caloric nystagmus with opposite direction of physiologic response. The mathematical significance of CP was horizontal coordinate of intersection point of the warm line (LW-RW) and cold line (LC-RC) in butterfly pattern calorigram. Detailed description is presented in figures.
Butterflies ; Caloric Tests ; Nystagmus, Physiologic

BACKGROUND AND OBJECTIVES: There can be 3, 192 syllables in Korean language but the frequencies of each syllables are variable. This study was aimed to investigate the frequencies of each Korean syllable in the everyday dialogue and to compare the result with the existing Korean phonetically balanced (PB) word list, which can provide the basic data for the standardization of Korean PB word list. MATERIALS AND METHOD: Using 33 materials (total 537, 245 syllables) collected from TV drama (MBC Best Theater), the author calculated the frequencies of each Korean syllables composed of initial consonant and vowel and compared with existing PB word list by computer program. RESULTS: Each syllable appeared in the different frequency pattern. The 138 of 399 syllables represented the 95% of everyday dialogue. CONCLUSION: This study showed that established PB word list was made relatively well but needs somewhat modification to reflect the actual frequencies of syllable in colloquialism.
Audiometry, Speech ; Drama ; Speech Discrimination Tests

BACKGROUND AND OBJECTIVE: lt has been suggested that the sequence of stimuli (right, left, warm and cold) might affect the slow phase velocity (SPV) of the caloric nystagmus in binaural bithermal caloric tests. This study was aimed to elucidate the effect of order of stimuli in caloric tests. MATERIALS AND METHODS: One hundred and two patients with dizziness have completed the test during the investigation period. The order of stimuli was selected in randomized and prospective manner. Statistically, the SPV from the first stimulus (SPV1) was compared with that from the second (SPV2). RESULTS: In the overall responses, the SPV from a warm stimulus was stronger than that from a cold stimulus. The SPV1 was more intense than SPV2 in a warm/warm/cold/cold sequence and warm/cold (nystagmus direction opposing)any/any sequence. A reverse result was observed in cold/warm (nystagmus direction enhancing) any/any sequence. CONCLUSION: The sequence of cold/cold/warm(nystagmus direction opposing) warm would have a minimal order effect on a caloric test.
Caloric Tests ; Dizziness ; Humans ; Nystagmus, Physiologic ; Prospective Studies*

No abstract available.
Computer Graphics ; Otolaryngology

BACKGROUND AND OBJECTIVE: Recent advances in the computer technology and the explosive increase in the internet contents have made it possible for us to calculate the exact frequencies of phonemes in the everyday dialogue of the Korean language, which can provide the basic data for the standardization of Korean phonetically balanced (PB) word lists. This study was aimed to investigate the frequencies of Korean phonemes and to compare the results with the existing Korean PB words lists. MATERIALS AND METHODS: The author has developed a computer program that can convert words into written sentences as they are pronounced, and calculate the frequencies of the Korean phonemes. This study used 10 materials (total 171,824 syllables) collected from several TV dramas and news shows. RESULTS: All materials showed a similar trend in the frequency pattern. According to the results, the existing PB words lists had too many /m/,/b/,/o/,/u/'s and too few /n/,/d/,/r/,/e/,/eu/,/i/'s. The most prominent discrepancy existed in the final consonants. CONCLUSION: The present study showed that the existing PB words lists need to be modified to reflect actual frequencies of phonemes.
Audiometry, Speech ; Drama ; Internet

No abstract available
Critical Pathways* ; Otolaryngology*

BACKGROUND AND OBJECTIVES: The alternative binaural bithermal (ABB) caloric test by Fitzgerald and Hallpike has become a standard procedure in caloric tests. But it brings patient discomfort and is a time consuming procedure. This study was aimed to investigate the efficacy of the monothermal caloric test as a replacement of ABB caloric test. MATERIALS AND METHOD: The results of 690 complete ABB caloric tests collected from 1997 through 1999 were analyzed retrospectively. We have examined the correlations between canal paresis value (CP) derived from an ABB caloric test and compared with the canal paresis value (CPmono) derived from the monothermal caloric component of a bithermal caloric test. RESULTS: There was a stronger correlation between CP and CPmono of warm monothermal component (Pearson correlation coefficient=0.86) than that of cold monothermal caloric test (Pearson correlation coefficient=0.55). Excluding cases with spontaneous nystagmus (n=553), similar results was observed. A warm monothermal caloric test has higher sensitivity and specificity than a cold monothermal caloric test. When the sensitivity of warm monothermal caloric test was more than 90%, the false positive rate was more than about 20%. The false positive rate was unacceptably high. CONCLUSION: The monothermal caloric test cannot be used as a replacement of ABB caloric test.
Caloric Tests* ; Diagnosis* ; Humans ; Paresis ; Retrospective Studies ; Sensitivity and Specificity