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ObjectiveThe aim of this study was to observe the 3-dimensional (3D; horizontal, vertical, and torsional) characteristics of nystagmus in patients with posterior semicircular canal canalithiasis (PSC-can)–related benign paroxysmal positional vertigo (BPPV) and investigate its correlation with Ewald’s.MethodsIn all, 84 patients with PSC-can were enrolled. The latency, duration, direction, and slow-phase velocity induced by the Dix-Hallpike test in the head-hanging and sitting positions were recorded using 3D video nystagmography (3D-VNG). The characteristics of the horizontal, vertical, and torsional components of nystagmus were quantitatively analyzed.Results3D-VNG showed that the fast phase of the vertical components and torsional components of left and right ear PSC-can as induced by the head-hanging position of the Dix-Hallpike test were upward, clockwise and counterclockwise, and horizontal components were mainly contralateral. The median slow-phase velocity of each of the three components for consecutive 5 s was 26.3°/s (12.3–45.8), 25.0°/s (15.7–38.9), and 9.2°/s (4.9–13.7). When patients were returned to the sitting position, the fast phase of the vertical and torsional components of nystagmus was reversed. Only 54 patients had horizontal components of nystagmus, and 32 of them remained in the same direction. The median slow-phase velocity of the three components for consecutive 5 s was 9.4°/s (6.0–11.7), 6.8°/s (4.5–11.8), and 4.9°/s (2.8–8.0). The ratios of the slow-phase velocity of the horizontal, vertical, and torsional components of the head-hanging position to the sitting position were close to 1.85 (1.0–6.6), 3.7 (1.9–6.6), and 5.1 (2.6–11.3). The ratios of the slow-phase velocity of the vertical to horizontal component, the torsional to horizontal component, and the vertical to torsional component of the head-hanging position were close to 3.3 (1.7–7.6), 3.9 (1.8–7.6), and 1.0 (0.5–1.8). The ratios of the slow-phase velocity of the vertical to horizontal component, the torsional to horizontal component, and the vertical to torsional component of the sitting position were close to 2.1 (1.1–6.8), 1.5 (1.0–3.8), and 1.2 (0.8–2.8).ConclusionThere were three components of nystagmus induced by the Dix-Hallpike test in patients with PSC-can. The vertical component was the strongest and the horizontal component was the weakest. The 3D characteristics of nystagmus were consistent with those of physiological nystagmus associated with the same PSC with a single-factor stimulus, in accordance with Ewald’s law.

Color quality evaluation is key to judging map quality, which can improve data visualization and communication. However, most existing methods for evaluating map colors are tedious and subjective m...

OBJECTIVE: To observe and analyze the changes in subjective visual vertical(SVV) after otolith reduction in patients with BPPV. METHODS: 46 patients with confirmed BPPV recieving successful otolith reduction were selected as the test group. 31 cases of posterior canal stones and 15 cases of horizontal semicircular canal stones, 29 cases of right ear and 17 cases of left ear. Fifty cases of healthy young volunteers were in the control group. Using the virtual reality SVV examination system, 0° SVV in the positive head were tested in the test group patients before and after the reduction of SVV, and were tested in the control group.The deviation angle of the SVV before and after the otolith reduction in the test group were analyzed. RESULTS: Before otoliths reduction, the SVV was (0.08±3.83)° of right BPPV and was (-1.69±2.23)° of left BPPV. After otoliths reduction, the SVV was (-1.52±3.74)° of right BPPV and was (-1.04±2.50)° of left BPPV. In the control group, the SVV was(-1.57±2.28)°. The changes of SVV deflection angle between the control group and the right BPPV before the otolith reduction, and before and after the otolith reduction in the right BPPV were analyzed, and the differences were all statistically significant. There was no significant difference in SVV deflection angle between the left BPPV(before and after reduction) and the control group. In the test group, after the otolith reduction, 18 cases had larger bias angles, 28 cases had smaller bias angle among which 13 cases the deviation angle even turned to the contralateral side. CONCLUSION: Utriculare dysfunction in patients with BPPV leads to the judgment error of SVV. Reduction of otolithoid can cause new stimulation to the eutricule and affect its functional status. SVV detection can provide help for the evaluation of utricular function in patients with BPPV.

Objective: To evaluate horizontal semicircular canal (HSC) effects according to Ewald's law and nystagmus characteristics of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) in the supine roll test.Methods: Patients with HSC-BPPV (n = 72) and healthy subjects (n = 38) were enrolled. Latency, duration, and intensity of nystagmus elicited by supine roll test were recorded using video nystagmography.Results: In patients with HSC-BPPV, horizontal nystagmus could be elicited by right/left head position (positional nystagmus) and during head-turning (head-turning nystagmus), and nystagmus direction was the same as that of head turning. Mean intensity values of head-turning nystagmus in HSC-BPPV patients were (44.70 ± 18.24)°/s and (44.65 ± 19.27)°/s on the affected and unaffected sides, respectively, which was not a significant difference (p = 0.980), while those for positional nystagmus were (40.81 ± 25.56)°/s and (17.69 ± 9.31)°/s (ratio, 2.59 ± 1.98:1), respectively, representing a significant difference (p < 0.0001). There was no positional nystagmus in 49 HSC-BPPV patients after repositioning treatment, nor in the 38 healthy subjects. No significant difference in head-turning nystagmus was detected in HSC-BPPV patients with or without repositioning.Conclusions: The direction and intensity of nystagmus elicited by supine roll test in patients with HSC-BPPV, was broadly consistent with the physiological nystagmus associated with a same HSC with single factor stimulus. Our findings suggest that HSC-BPPV can be a show of Ewald's law in human body.

OBJECTIVE: To study whether the warm/cold air injection sequence affects the test results in the caloric test, and provide a basis for the specification and quality control of the caloric test. METHODS: Video nystagmography and warm and cold air stimulation apparatus were applied for caloric test. Thirty healthy volunteers (60 ears) were divided into two groups of 15 (30 ears) each. The first group was given cold air stimulation followed by warm air stimulation, and the second group was given heat followed by cold. The differences in nystagmus maximal slow phase velocity (SPV), semicircular canal paresis (CP) and dominant preponderance (DP) were compared between the two groups of subjects under different perfusion sequences of caloric test. RESULTS: The intensity of nystagmus evoked by subjects in group 1 (cold first and then warm) and group 2 (warm first and then cold) were similar. Paired t-test showed that intra-group analysis of the SPV values of the two groups, comparison of the intensity of nystagmus evoked by different temperatures of the same ear or different sides of ear with the same temperature, the difference was not statistically significant (all P>0.05). Independent samples t-test showed that between-group analysis of SPV values of two groups, the intensity of nystagmus induced by the same and different temperature stimuli in the ipsilateral ear, the difference was not statistically significant (all P>0.05). Independent samples t-test showed that the CP values of the two groups were analyzed between groups, and the difference was not statistically significant (all P>0.05). Independent samples t-test showed that DP values of both groups were in the normal range and the difference was not statistically significant (all P>0.05). CONCLUSION: Different perfusion sequences of warm and cold air do not affect the results of caloric tests, and the order of warm and cold air stimulation is not the normative and quality control research direction of caloric test.

Creating appropriate colour schemes is challenging for both novice and experienced cartographers. This paper introduces an artificial bee colony (ABC) algorithm to automatically create various colo...

OBJECTIVE: Analysis of normal reference value of smooth pursuit test for normal young people. METHOD: Thirty normal young volunteers were tested by Synapsys videonystagmography. The maximum horizontal tracking angle was 30 °, the vertical maximum tracking angle was 20°, and the frequency was 0.30 Hz, 0.45 Hz and 0.60 Hz, respectively, and the gain under different conditions is used as the observation index. RESULT: When the frequency is 0.3 Hz, 0.45 Hz, 0.60 Hz, the left and right horizontal gain is 0.92±0.07/0.93±0.07, 0.87±0.08/0.88±0.11, 0.79±0.11/0.78±0.13, respectively, and the asymmetry of left/right gain is 0.021±0.017, 0.031±0.026, 0.037±0.040; the up and down vertical gain is 0.82±0.16/0.80±0.16, 0.78±0.17/0.72±0.15, 0.68±0.20/0.61±0.15, and the asymmetry of the upper/lower gain is 0.046±0.045, 0.069±0.058, 0.109±0.076. Comparing and analyzing the paired left and right gain values of the three frequencies by paired t test, the differences were not statistically significant (P>0.05). Paired t -test of gain value for different frequency of up and down stationary tracking, the difference was not statistically significant at 0.30 Hz(P>0.05), but the gain at 0.45 Hz and 0.60 Hz has significant difference(P < 0.05). Comparing the gains of different frequencies in the same direction, the differences in analysis of variance were statistically significant(P < 0.05). CONCLUSION: The gain value of smooth pursuit test for normal young people can be affected by tracking frequency and direction. At the same frequency, the left/right tracking of 3 frequencies and the up/down tracking gain values of 0.30 Hz are symmetrical, but at 0.45 Hz and 0.6 Hz, the up tracking gain is greater than the down tracking gain, and the gain value in the same direction gradually decreases with the increase of frequency, is the clinical smooth pursuit test is mainly based on 0.30 Hz.

Creating a satisfying qualitative color scheme from scratch may be difficult for novice mapmakers and experts. A probability-based method is proposed to identify knowledge regarding qualitative color selection from readily available color schemes and formalize the discovered knowledge to assist in color creation. An unsupervised method to extract the general trends of color selection is presented, and the issue of qualitative color selection is translated into a multi-constraint optimization problem. A feasible solution for achieving the global optimum is then provided. A probability-based method is also proposed to match abstract color values with specific mapping features. This proposed approach is evaluated in a case study. The results of the case study suggest that the proposed method allows users to create qualitative color schemes more efficiently and confidently.

To investigate the characteristics and clinical utility of vestibular autorotation test (VAT) in patients with vestibular migraine.This study included two groups, an experimental group (441 patients) and a control group (65 healthy subjects). Both groups undertook VAT; the parameters evaluated were horizontal gain/phase, vertical gain/phase and asymmetry. The differences in VAT results between the two groups were investigated.There were no statistical differences between the VAT data of the control group when compared to the reference value from the manufacturer (p .05). There were statistically significant differences in VAT results between the experimental and control group, namely elevated horizontal gain at frequency 2, 3, 4 and 5 Hz, horizontal phase delay at frequency 2, 4, 5 and 6 Hz, elevated vertical gain at frequency 2 6Hz and vertical phase delay at frequency 4 6Hz.The results of this study using VAT in VM patients demonstrate elevated horizontal gain, vertical gain and delay in horizontal phase, vertical phase. We suggest the application of VAT as a diagnostic tool which may provide objective evidence that can contribute to the diagnosis of VM and also in differential diagnosis.

Topological models in Euclidean space are difficult for spatial analysis because of the lack of direct representation of geometric three-dimensional (3D) object information. A 3D cadastral data model in the form of boundary representation based on conformal geometric algebra (CGA) is proposed to realize the integrated representation of geometric and topological information based on previous research. On the basis of the 3D cadastral data model based on CGA and basic geometric operators, self-defined geometric algebraic operators are designed using the advantages of geometric algebra in spatial topological calculation. A computation framework for cadastral parcel topological error detection is put forward based on those self-defined geometric operators. A case study is designed to verify the feasibility of topological error detection methods proposed in this paper. This study is an expansion of research for a 3D cadastral data model based on CGA.

Secretory otitis media (SOM) is a common and frequently occurring disease featured by middle ear cavity exudant, ear nausea, and hearing loss. Morbidity of children is higher than that of adults. The pathogenesis and etiology of SOM are clear so far. Previous reports concluded that the mechanical obstruction and dysfunction of the eustachian tube are among the important causes of infection. The mechanism of infection and immune response in the pathogenesis of SOM is currently becoming a research hot spot, providing a reference for further study.

To discuss the characteristics of subjective visual gravity (subjective visual vertical/horizontal, SVV/SVH) and assess its clinical application for peripheral unilateral vestibular compensation.69 cases of acute peripheral unilateral vestibular dysfunction patients (case group) accepted SVV/SVH, spontaneous nystagmus (SN), caloric test (CT) and other vestibular function tests. 49 healthy people (control group) accepted SVV/SVH only. SVV/SVH, SN and unilateral weakness (UW) were selected as for the observation indicators. The correlations between SVV/SVH, SN, UW and courses were investigated respectively, as well as the characteristic of SVV/SVH, SN in period of vestibular compensation.Among case group SVV, SVH positive in 42 patients(60.9%) and 44 patients(63.8%), the absolute values of the skew angle were in the range between 2.1°-20.0°, 2.1°-22.2°. Skew angles of SVV/SVH in control were in the range between -1.5°-2.0° and -2.0°-1.6°, and had no statistical significance with case group(t=5.336 and 5.864, P0.05). SN-positive 28 cases (40.6%), the range of intensities at 2.4°-17.1°; UW-positive 50 cases (72.5%). In case group, positive correlation between SVV and SVH(r=0.948, P=0.00), negatively correlated between SVV/SVH and SN respectively(r values were -0.720, -0.733, P values were 0.00), no correlation between the skew angle of SVV/SVH, strength of SN and UW value(r values were 0.191, 0.189, and 0.179, P0.05), there was no correlation between the absolute value of SVV, SVH, SN, UW with the duration (rs values were -0.075, -0.065, -0.212, and 0.126, P0.05).Subjective visual gravity can be used not only to assess the range of unilateral peripheral vestibular dysfunction, but also help assess the static compensatory of otolithic, guidance and assessment of vestibular rehabilitation.

Basic scientific research of land cover in Suqian is fundamental to ensure the sustainability of land resource management. The major study is to monitor the confusable land cover types according to the remote sensing, and the integrated information. It supplies a new direction for integrating date sets and improves the monitor on land cover. It presents a simple fusion approach for integrating time series of the MODIS Vegetation Index products and Landsat TM data. The fusion supplies the prior probability to distinguish forest with crop for guiding supervised classification which served in monitoring forest quantities-increasing in future. The entire operation just uses primarily the fusion method from the fuzzy mathematics to achieve various kinds of information with some simple parameters. However, the fusion is a spatial feature classification conduced remote sensing training mask data blending the advantages of the phonological information, the feature characteristics and the spatial-temporal data.

To explore the clinical values of Sensory Organization Test (SOT) of dynamic posturography in the diagnosis of peripheral vertigo.A total of 112 patients with peripheral vertigo were retrospectively analyzed. All the patients firstly underwent the inspection of SOT followed by caloric test. The results were conducted a comparative analysis. Assessments of SOT evaluated the patient's effective use of visual, vestibular, and somatosensory information for balance control during a variety of changing task conditions. The unilateral weakness was selected as assessment parameter of caloric test. Fourty-two healthy subjects were selected as control group underwent the dynamic posturography.Among the 42 cases of control group, results of SOT in dynamic posturography were normal. The SOT composite scores owned a significant difference between control and peripheral vertigo subjects. Among the 112 cases with peripheral vertigo, results of SOT in dynamic posturography were abnormal in 37 cases, with a sensitivity of 33.0%; caloric test was abnormal in 72 cases, with a sensitivity of 64.3%. There existed a significant difference between dynamic posturography and caloric test.SOT is a key test in dynamic posturography that reflects the balance reconstruction after peripheral injury, and provides information about the integration and proportion of the visual, proprioceptive, and vestibular components of balance.

The aim of this study was to evaluate the effects of obstructive sleep apnea-hypopnea syndrome (OSAHS) on semicircular canal function.By means of a series prospective study at Department of Otolaryngology Head and Neck Surgery of our hospital, the study was performed on 77 patients suffering from OSAHS in a period from 2012 to 2014, who underwent polysomnography (PSG) and caloric test. The maximal slow-phase velocity (SPV) and unilateral weakness (UW) were used to measure the vestibular function. Severity of OSAHS was evaluated by the lowest oxygen saturation (LSaO₂) and apnea hypopnea index (AHI). The SPV after cool was signed, warm test was performed for each ear, and the sum of left ear SPV were calculated, and then, the SPV of right ear was counted as the same way. Finally, the relationships between LSaO₂, AHI, age, BMI, and SPV of caloric test were analyzed.Caloric vestibular tests in the 77 OSAHS patients demonstrated abnormal findings in 52 patients (67.5%) and normal vestibular functions in the remaining 25 patients (32.5%). Of the 52 patients with an abnormal test result, 16 (20.8%) patients had unilateral vestibular hyporeflexia and 36 (46.7%) patients revealed a bilateral vestibular hyporeflexia. There was no linear relationship between AHI, age, BMI with SPV of caloric test (P0.05). The SPV had significant difference between Lower LSaO₂group (LSaO₂50%) and higher LSaO₂group (LSaO₂≥ 80%) (P0.05). LSaO₂was lower in patients undertaken bilateral vestibular hyporeflexia.OSAHS patients with long-term intermittent hypoxia can disturb the vestibular organs and reduce semicircular canal function. The heavier hypoxemia will lead to the lower reflex of semicircular canal, with the heavier degree of hypoxemia, and the bilateral horizontal semicircular canal involvement may also be higher at the same time. Due to the effect of vestibule centre compensatory, OSAHS patients lack of dizziness and symptoms from balance disturbances such as typically acute vestibular damage.

To discuss the video head impulse tests (vHIT) application values in assessment of the vestibular nerves, function in sudden deafness patients with vertigo.There were 60 cases (120 ears) of healthy volunteers as control group, and 182 cases (182 ears) of sudden deafness with vertigo patients as study group. The study group received vHIT and caloric test, and the control group received vHIT. Functions of vestibular superior and inferior nerves were analyzed by the gains of vHIT and the nystagmus, s unilateral weakness of caloric test, with SPSS17.0 software.The values of vHIT-G of the six semicircular canals in the control group were normal distribution and no statistical significance among them (F = 0.005, P = 1.000). The vHIT-G averages of both sides of anterior, horizontal and posterior semicircular canals were (15.20 ± 11.00) %, (15.30 ± 13.30) %, and (15.15 ± 14.72) % respectively. In the study group, the vHIT-G of the affected side were (21.73 ± 14.84) %, (21.20 ± 28.24) %, and (19.22 ± 23.50) %, with normal distribution, and in which statistical significance was detected comparing with those in the control group (P0.05). The positive rates were 26.9% (49/182) in vHIT, 70.3% (128/182) in caloric test. Significant difference (P0.05) was observed between vHIT and caloric test examined by chi-square test. According to the results of vHIT, there were 15 cases (8.2%) damaged vestibular superior and inferior nerves areas, 19 cases (10.4%) damaged the superior vestibular nerve area, and 15 cases (8.2%) damaged the inferior vestibular nerve area. In combination with caloric test results, it was shown that there were 29 cases (15.9%) damaged vestibular superior and inferior nerves areas, 101 cases (55.5%) damaged the superior vestibular nerve area, and 1 case (0.5%) damaged the inferior vestibular nerve area.vHIT can assess the function of six semicircular canals and illustrate high frequency of vestibular nerves. Caloric test combined with vHIT have more advantages to comprehensive assess vestibular damage of sudden deafness patients with vertigo.

To investigate the clinical significances and formation mechanism by analyzing the characteristics of the reverse phase nystagmus parameters from benign paroxysmal positional vertigo (BPPV) positioning test.There were 183 cases with BPPV, including 108 cases (59.0%) of posterior semicircular canal canalithiasis, 55 cases (30.1%) of horizontal semicircular canal canalithiasis, and 15 cases (8.2%) of horizontal and posterior semicircular canal cupulolithiasis and 5 cases (2.7%) of anterior semicircular canalithiasis . The video-nystagmography was utilized in positioning tests to induce nystagmus. The direction, intensity, time parameters characteristic of vertical nystagmus in Dix-Hallpike test and horizontal nystagmus in roll test were analyzed and compared.There were no reversal phase nystagmus in 15 cases of semicircular canal cupulolithiasis and 5 cases of anterior semicircular canalithiasis. After the disappearance of vertical nystagmus which induced by hanging position (the first phase nystagmus) in 108 cases of posterior semicircular canalithiasis of Dix-Hallpike test, there was 54 cases(50.0%) of posterior semicircular canal canalithiasis displayed downward vertical nystagmus (reverse phase nystagmus) . The latency, duration time and intensity of the first phase nystagmus and reverse phase nystagmus were [(2.00 ± 1.10) s, (3.54 ± 1.42) s], [ (16.27 ± 4.95) s, (61.65 ± 33.69)s] and [ (51.80 ± 25.25) °/s, (10.65 ± 6.29)°/s] respectively; 43 cases(78.2%) of horizontal semicircular canal canalithiasis displayed the opposite to turning head (reverse phase nystagmus) after the horizontal nystagmus, similar with turning head disappeared in Roll test. The latency, duration time and intensity of the first phase of nystagmus and reverse phase nystagmus were [ (1.67 ± 1.07) s, (3.57 ± 1.89)s], [ (25.19 ± 9.74) s, (70.48 ± 40.26)s] and [ (68.47 ± 30.18) °/s, (11.22 ± 8.78)°/s] respectively. Comparing with the latency, duration time, intensity of first phase nystagmus and reverse phase nystagmus of posterior and horizontal semicircular canal canalithiasis, the differences had statistical significances (P0.05). Comparing with the first phase nystagmus of reverse phase and no reverse phase nystagmus canalithiasis, the difference of nystagmus intensity had statistical significances (P0.05); but the differences of latency and duration of nystagmus had no significant difference (P0.05).It is common in PSC-Can and HSC-Can patients that reverse phase nystagmus is one of the clinical features of canalithiasis. It appears in side head position of Rolling test or the hanging of Dix- Hallpike test. More power of the first phase nystagmus has, reverse phase nystagmus will be induced much easier. In comparison of the reverse phase nystagmus, the first phase nystagmus has the shorter incubation and duration, but it has more power. It is helpful to avoid interruptions of clinical statolith positioning and reset since we recognize the reverse phase nystagmus. The mechanism might be similar to the vestibular mirror image nystagmus. It is another form of the vestibular mirror image nystagmus in BPPV patients.

To analyze the occurrence and probable etiological factors of benign paroxysmal positional vertigo (BPPV).one hundred and twenty four BPPV cases were inquired histories, classified into different groups and analyzed relevant diseases. All patients were taken Caloric tests before Canal repositioning procedure, and compared the differences of unilateral weakness (UW) and semicircular canal involved between BPPV patients with and without relevant diseases.There were 97 (78.2%) patients with relevant diseases while 27 (21.8%) without. Ninety-two (74.2%) patients with abnormal UW. To compare the normal and abnormal UW, posterior canal and lateral canal with abnormal UW values, unilateral or bilateral of abnormal UW values, consistency of abnormal UW side and BPPV side between BPPV patients with and without relevant diseases, there were no significant differences (Chi-square values were 0.000, 0.000, 0.306, 0.027, P0.05).BPPV patients with relevant diseases are common, which mainly occurs in middle-aged or aged people and female. Otolith ecclesiis and dysfunction of semicircular canal may have the same etiological factors. Caloric tests may do help to analyze the BPPV etiological factors.

Symbol is one of the cores of GIS and mapping system. However, difference of design styles, data structures, storage methods and render strategies among the systems leads to no synchronous sharing of map symbols when sharing geographic data. Taking map symbols as a breakth-rough, the paper analyzes and compares the ArcGIS symbol model with the SLD and provides the mapping mechanism between ArcGIS symbols and SLD symbols to study the symbol sharing between them. The analytic result shows that the SLD symbols all can be converted to the ArcGIS symbols, but only small part of ArcGIS symbols can be converted to the SLD symbols. The ArcGIS symbol system is more consummate but not perfect and the closed symbol format goes against to symbol sharing. And the SLD symbol format is open, but it is too unitary to meet the needs of Cartography. Therefore, a common symbol model is required to synthesize ArcGIS symbols and SLD symbols to achieve the map symbol sharing.

Symbol and data are two cores of GIS and mapping systems. However, with the full sharing of geographical data, symbol information is not shared synchronously and there is a large number of low-level duplication in the process of making symbols. Based on symbol sharing problem among different systems, point symbols will be taken as a breakthrough to study symbol sharing between CAD and GIS, and to provide the mapping mechanism from CAD symbols to TrueType fonts. Experiment validates the feasibility of sharing between CAD blocks and TrueType-based GIS point symbols and offer approach for one map symbol library with multi-usage.

The formal representation of topological relations plays a very important role in process of spatial query, spatial analysis and spatial reasoning. Most current models support a single representation of geometry and topology at a fixed resolution. While it often happens that different applications take into consideration spatial data/topological relationship, with the same 3D scene date, under different viewpoints, in different geometric forms and/or with different resolutions. In this case, a topology model for multiple topological representations is needed. In this paper, we propose a new approach based on combinatorial maps, which focus on both multiple topological representations under the situation of LOD and Feature semantic/spatial aggregation and the consistency of topology.

To analyze the result of smooth pursuit test (SPT) in unilateral vestibular peripheral vertigo and investigate its influencing factors.Smooth pursuit test (SPT) and spontaneous nystagmus (SN) were examined in one hundred and eighty-five patients with unilateral peripheral vertigo (case group) and 51 normal persons (control group) by Video-Nystagmography (Synapsis, France), and the gain of SPT and SN were selected as the observation parameters in order to analyze the waveform and gain of SPT and the relativity between SN and the gain of SPT.Of the 185 patients, 105 (56.8%), 72 (38.9%) and 8 (4.3%) cases produced I , II and III waveforms respectively. Of these patients, 58 (31.4%) demonstrated SN and none had IV waveform. While of 51 normal persons, 38 (74.5%), 13 (25.5%) persons produced I and II waveforms respectively and there were no III, IV waveforms or SN. There was statistical significance between the strong and weak gain of SPT in these two groups. Weak gain was significantly different between two groups. The strong and weak gain of SPT in case group were 0.86 +/- 0.06, 0.80 +/- 0.06; 0.78 +/- 0.09, 0.65 +/- 0.1; 0.68 +/- 0.13, 0.45 +/- 0.12. The relativity between SN and the gain of SPT was positive when they had same direction (r(s) = -0.63, P0.05) and negative when opposite (r(s) = 0.34, P0.05).I , II, III three waveforms of SPT could appear in unilateral vestibular peripheral vertigo and the corresponding gains are gradually decreasing. SN is the influencing factor of SPT.

To analyze the value of positioning diagnosis of VNG (Videonystagmograph) in patients with benign paroxysmal positional vertigo (BPPV).One hundred and twenty-six patients with BPPV were enrolled in this retrospective study. Their positional nystagmus recorded by VNG in Dix-Hallpike and roll tests were analyzed to summarize the characteristics of nystagmus on nystagmography of various BPPV.Of 126 patients with BPPV diagnosed in our center, the posterior semicircular canals (PSC) were involved in 98 patients (77.8%), whereas the horizontal semicircular canal (HSC) and anterior semicircular canal (ASC) were involved in 17 (13.5%) and 5 (3.9%), respectively. Six patients (4.8%) confirmed combined-BPPV had HSC-BPPV and ipsilateral PSC-BPPV. Twenty-eight patients with PSC-BPPV had reversal phase on nystagmography. The nystagmus of patients with P/ASC-canalithiasis showed upward/downward on the vertical phase of nystagmography and orientated the opposite side on horizontal phase in the head hanging position, and the nystagmus reversed when returned to sit. Nystagmus on horizontal phase could be provoked when the head turned to both sides of the roll tests in patients with HSC-BPPV. If the nystagmus and the head-turning shared the same direction, then HSC-canalithiasis was confirmed, and the direction of the head-turning which provoked the stronger nystagmus indicates the lesion side. If the nystagmus and the head-turning had the opposite direction, then HSC-cupulolithiasis was confirmed, and the direction of the head-turning which provoked the weaker nystagmus indicates the lesion side.Positional nystagmus can be recorded objectively using VNG, According to which positioning the semicircular canal involved would be easier and more accurate. The recording conserved also could be helpful for clinical diagnosis and repositioning of BPPV.

To investigate the screening value and the reliability of the monothermal caloric tests (MCT) in evaluating vestibular function.One thousand and four hundred and six vertigo patients were divided into two groups. Seven hundred and five cases were stimulated by different temperature air from cold to warm. The caloric test sequence of other 701 cases was opposite. The first stimulated cold or warm air test was regarded as monothermal cold caloric test (MCCT) or monothermal warm caloric test (MWCT). The unilateral weakness (UW) and directional preponderance (DP) of the bithermal caloric tests (BCT) and the UW of the MCT were calculated. By defining the BCT results as the standard, the sensitivity, specificity, Youden's index and kappa were calculated.Four hundred and twenty-eight showed abnormal BCT and MCCT. One hundred and forty-five showed normal BCT and MCCT. 85, 47 showed isolated abnormal BCT and abnormal MCCT respectively. The sensitivity of the MCCT was 83.4%, specificity was 75.5%, Youden's index was 0.589 and kappa was 0.555 (P0.01). Four hundred and twenty-nine showed abnormal BCT and MWCT, 130 showed normal BCT and MWCT. 82, 60 showed isolated abnormal BCT and abnormal MWCT respectively. The sensitivity of the MWCT was 84.0%, specificity was 68.4%, Youden's index was 0.524 and kappa was 0.505 ( P0.01). The sensitivity of the MCCT and MWCT were 86.9% and 86.9% respectively when cases accompanied by spontaneous nystagmus (SN) were excluded. The sensitivity of the MCCT and MWCT were 89.3% and 88.1% respectively when cases with abnormal DP were excluded.The high false-positive and false-negative rate of the MCT limit the usefulness as a screening test due to the influence of DP and SN.