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Clinical Epidemiological and Neurotological Approaches to Migraine-related Vertigo and Dizziness
No full text目的 本研究之主要目的為分析與偏頭痛相關之眩暈及頭暈患者之臨床表現，並尋找與治療效果相關之因子。此外，一併探討不同診斷疾病群間之關係。法 病患來源為自2007年7月至2008年1月於耳鼻喉科眩暈特別門診就診之病患，所有病患均接受一系列之檢查並排除其他可能之診斷。研究之收案條件為5次以上之偏頭痛與2次以上之前庭症狀，計110名病患納入本研究。每位患者都接受制式化的當面訪談，並收集相關之臨床症狀與檢查結果，再依據基底型偏頭痛 ( BtM)、確定偏頭痛型眩暈 (dMV)、與疑似偏頭痛型眩暈(pMV) 之診斷基準進行分類比較。除了7名患者未完成治療與追蹤外，其他病人均接受藥物治療為期三個月，結束後依病歷記載分析其治療結果。果 病患之平均年齡為40歲，多數為女性（85％）且有偏頭痛之家族史（72％），症狀發作之年齡大多介於20至 29歲之間，且61％之患者以頭痛為初始表現。106位（96％）患者均表示有一種以上之偏頭痛誘發因子。與治療結果相關之因子為年齡 (年齡每小10歲之危險性為2.38倍，95%信賴區間： 1.39 ~ 4.07)，前庭症狀之發作頻率 (危險性=7.73, 95%信賴區間：2.05 ~ 19.1)，以及異常的視運動眼振測驗 (危險性=5.40, 95%信賴區間： 1.60 ~ 18.2)。此外，BtM 與 dMV兩組之臨床表現相似，包括偏頭痛之相關症狀、動暈症、以及頭痛與頭暈間之時序性，但BtM 組有較多神經學症狀與較頻繁之發作頻率，且眼振電圖檢查出現較多中樞性徵象。反之，pMV組則屬病症最輕微。論 本研究收集了與偏頭痛相關之眩暈及頭暈在台灣地區之代表性族群，且臨床表現與文獻之記載相符。與治療結果相關之重要因子包括年齡、前庭症狀之發作頻率與異常之視運動眼振測驗。三組不同診斷疾病群之間的關係可能意味此一症候群在臨床嚴重度的不同，其中基底型偏頭痛之症狀最為嚴重且治療成果最不理想。Objective This study was designed to analyze the clinical manifestation of patients with migraine-related vertigo and dizziness, and explore the association between clinical characteristics and treatment effectiveness. The relationships between different diagnostic groups were investigated as well. ethod The source population was comprised of patients visiting a vertigo special clinic from July 2007 to January 2008. Subjects with other potential diagnoses were excluded. Inclusion criteria consisted of > 5times of migrainous headache and > 2 times of vertigo/dizziness episodes. One-hundred and ten subjects were enrolled and eligible for this study. All the patients received structured interview of clinical presentations, and the results of audiovestibular function tests were recorded. Further classification of study subjects were based on the diagnostic criteria of basilar type migraine (BtM), definite migrainous vertigo (dMV) and probable migrainous vertigo (pMV). Excluding 7 subjects lost from clinic, treatment effectiveness was evaluated in 103 subjects after a consecutive 3-month medication.esult The demographic characteristics constitute a mean age of 40 years old, female predominance (85%), strong family preponderance (72%), plateau of onset of symptoms around 20-29 years old, and headache as the first presenting symptom in 61% of subjects. Migraine precipitants were identified in 106 subjects (96%). Significant factors associated with poor response are: younger age at presentation (adjusted odds ratio (aOR) =2.38 for each 10-year decline, 95% confidence interval (CI): 1.39 ~ 4.07), frequent vestibular episodes (aOR=7.73, 95% CI: 2.05 ~ 19.1), and abnormal optokinetic nystagmus (OKN) tests (aOR=5.40, 95% CI: 1.60 ~ 18.2). Food precipitation showed borderline correlation with treatment response (aOR=0.31, 95% CI: 0.09 ~ 1.04). Furthermore, BtM and dMV group are similar in clinical presentation, e.g. migrainous symptoms, motion sickness and sequential relationship between migraine and vertigo, but differs in that BtM had more extensive neurological symptoms, more frequent vestibular symptoms, more central signs on electronystagmography tests, and also, the worst treatment effectiveness. In contrast, pMV group represents the least severe clinical manifestation.onclusion This study enrolled a representative sample of migraine-related vertigo and dizziness in Taiwan. The significant factors in relation to treatment effectiveness are identified, i.e. frequency of vestibular episodes, age at presentation, and OKN abnormalities. The relationship between these three diagnostic groups is most likely a distribution of severity across the disease spectrum, with BtM presenting the most extensive involvement of the brainstem and the worst treatment response.Table of Contents試委員會審定書……………………………………………ibstract…………………………………………………….. ii 文摘要………………………………………………………..iv. Introduction……………………………………….. ….1. Literature review…………………………………………3.1 Clinical presentation ………………………………..3.2 Objective assessment ………………………………...6.3 Pathophysiology………………………………………...8.4 Nomenclature and diagnostic criteria…………….10.5 Therapeutic options and studies of treatment effectiveness......................................12. Objectives…………………………………………………15. Subjects and Methods………………………………………………………….17.1 Study design and enrollment of subjects………..17.2 Data collection and definition of variables……20.3 Audiovestibular function test………………………22.4 Diagnostic and classification criteria………..24.5 Result analysis and statistical methods…………26. Results……………………………………………………28.1 Descriptive analysis of clinical manifestation…28.1.1 Demographics…………………………............…28.1.2 Characteristics of vestibular symptoms…………30.1.3 Characteristics of migrainous headache……….32 .1.4 Audiovestibular function results…………………34.2 Correlation between clinical manifestation and treatment effectiveness…...........................35.2.1 Univariate analysis…………………………..…….36.2.2 Multivariate analysis……………..……….……..42.3 Comparison between different diagnostic groups…45.3.1 Demographics …………………………………………45.3.2 Characteristics of vestibular symptoms………46.3.3 Characteristics of migrainous headache ….……48.3.4 Audiovestibular function results…………………51.3.5 Multivariate analysis of differentiating factors …………………......................................52.3.6 Treatment effectiveness of three diagnostic groups………………..................................53. Discussion…………………………………………………54.1 Study population…………………………………………54.2 Clinical manifestation of enrolled subjects……55.3 Treatment effectiveness and its correlation with clinical manifestations.............................57.4 Relationship between different diagnostic groups61.5 Limitations……………………………….…………....67. Conclusion …………………………………………………69. Perspectives………………………………………………..70. References……………………………………………………710. Appendixppendix I. Summary of diagnostic criteria………………75ppendix II. Protocol of structured interview…………76ppendix III. Informed consent………………………………77Appendix IV. Food precipitation inquiry………7
Earlier and Later Components of Tone Burst Evoked Myogenic Potentials
No full textThe aim of this study was to further investigate the response rates, thresholds, latencies and amplitudes of the earlier and later components of tone burst evoked myogenic potentials (TEMPs) in conditions of binaural and monaural stimulation and recordings in a group of normal subjects in response to a 500-Hz tone burst. Each subject underwent simultaneous binaural acoustic stimulation with bilateral recording (B-TEMP) initially, then monaural acoustic stimulation with ipsilateral recording (M-TEMP) on another day. The results showed 100%, 100%, 54%, and 23% response rates for the earlier components of B-TEMPs, when using 105, 95, 85, and 75 dB acoustic stimulation, respectively. It exhibited a significant decrease in the response rate when the stimulus intensity was attenuated from 95 to 75 dB. In addition, no significant difference in the response rate of the earlier components existed between B-TEMPs and M-TEMPs. For the later components of B-TEMPs obtained from 105, 95, 85, and 75 dB acoustic stimulation, the response rates were 85%, 85%, 62%, and 42%, respectively, higher than those of M -TEMPs significantly. Nevertheless, there were no statistical differences in the mean latencies of each peak ( p13, n23, n34 , and p44) between B-TEMPs and M-TEMPs under similar stimulus intensity. Meanwhile, no significant relationship existed between the stimulus intensity and the latency, regardless of B-TEMPs or M-TEMPs. Comparing the relative amplitudes between B-TEMPs and M-TEMPs, the former displayed significant smaller p13-n23 amplitude, but larger n34-p44 amplitude. However, the mean thresholds for the earlier and later components between B-TEMPs and M-TEMPs did not differ significantly. In conclusion, monaural acoustic stimulation with ipsilateral recording may elicit larger amplitude of the earlier components, whereas binaural acoustic stimulation with bilateral recording evokes higher response rate and larger amplitude of the later components. Although the nerve pathways for both components are different, the thresholds for these potentials do not differ significantly, indicating that both components may, at least in part, share a common origin, but different pathways . (C) 2004 Elsevier B.V. All rights reserved
Potential Usefulness of Tl-201 Spect for Differentiating Radionecrosis in an Irradiated Nasopharyngeal Carcinoma Patient
No full textDifferentiation between cerebral radionecrosis and intracranial relapse in irradiated nasopharyngeal carcinoma( NPC) patients challenges the clinicians, especially when clinical manifestation and MRI findings are inconclusive. A 63-year-old NPC patient had intermittent dizziness and unsteady gait 3 years after irradiation. An ice water caloric test revealed absent response on the right ear, which was compatible with an enhanced lesion at the right temporal lobe on MRI scan. Furthermore, abnormal focally increased uptake over the anteriomedial aspect of the right temporal lobe was disclosed on 18-fluoro-2-deoxyglucose (FDG ) positron emission tomography (PET), which suggested intracranial relapse. Conversely, serological study for Epstein-Barr viral titer was within normal limits, arguing against either recurrent or metastatic NPC. Hence, thallium( Tl)-201 single photon emission computed tomography (SPECT) was subsequently conducted, which failed to demonstrate abnormal thallium accumulation in the corresponding area. Accordingly, radiation necrosis of the temporal lobe rather than intracranial relapse is considered. The patient was rather well without locoregional recurrence or distant metastasis 2 years after presentation
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Relationship between Basilar-Type Migraine and Migrainous Vertigo
No full textObjective.-This study compared clinical manifestations and audiovestibular function tests among subjects of basilar- type migraine ( BtM), definite and probable migrainous vertigo (dMV and pMV), in order to investigate the relationship between them. Background.-Various diagnostic criteria such as BtM, dMV, and pMV have been proposed. However, a comparison between these diagnostic groups has not been conducted before. Methods.-This study enrolled 77 subjects, including BtM in 15, dMV in 30, and pMV in 32 patients. All patients received structured interview of clinical presentations and underwent a battery of audiovestibular function tests. Results.-Demographic features were similar between 3 groups, including age, gender, precipitating factors, and family preponderance. When considering the clinical manifestations, for example motion sickness, migrainous symptoms, and sequential relationship between headache and vertigo, BtM and dMV groups shared similar features, but differed from pMV group. As regards to differentiate between BtM and dMV patients, the former revealed higher occurrence rates than the latter in relation to the frequency of vertigo attacks, neurological symptoms, and saccadic dysmetria. Conclusion.- The relationship between BtM, dMV, and pMV refers to a distribution of severity across the disease spectrum of migraine- related vertigo. Of them, BtM group presents the most severe form in clinical manifestation and brainstem involvement, followed by dMV, and pMV is the mildest form
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Real-time ultrasound elastography: an assessment of enlarged cervical lymph nodes
No full textTo determine the efficacy of real-time elastography (RTE), compared with our previously proposed prediction model, in the detection of malignancy in cervical lymph nodes (LNs).
One hundred and thirty-one patients underwent ultrasound-guided fine needle aspiration biopsy (ultrasound FNAB) after ultrasound and RTE evaluation. The formula of the RTE scoring system was a four-point visual scale, based on a previously determined model. The formula of the prediction model was: . An extended model was constructed with four previous predictors and elasticity scores, using a logistic regression model.
Final histology revealed 77 benign and 54 malignant LNs. In the elasticity score system, sensitivity was 66.7 %, specificity was 57.1 %, the positive predictive value (PPV) was 52.2 % and the negative predictive value (NPV) was 71.0 %. In the prediction model system, sensitivity was 79.6 %, specificity was 92.2 %, the PPV was 87.8 % and the NPV was 86.6 %. When the extended and the original model were compared, the areas under the receiver operating characteristic curve (c-statistic) was 0.94 and 0.95, respectively (P > 0.05).
Qualitative RTE offers no additional value over conventional ultrasound in predicting malignancy in cervical LNs.
An ultrasound system can help in the assessment of cervical lymph nodes.
Grey-scale and power Doppler ultrasound remain fundamental for neck nodal evaluation.
Qualitative real-time elastography provided no additional value compared with current prediction models
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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