Objective To compare the etiology of vertigo patients between flying personnel group and ordinary group and to provide evidence for the accurate diagnosis of vertigo or dizziness and the aeromedical assessment. Methods One thousand and sixteen ordinary vertigo patients,who were diagnosed by the Vertigo Center of Former Air Force General Hospital of PLA in the period from January 2017 to April 2018,were assigned to ordinary group.One hundred and fifty-three vertigo inpatients and outpatients of flying personnel,who were diagnosed by the hospital in the period from September 1984 to Augut 2018,were selected as flying personnel group.The etiological stratification analysis was conducted upon the gender and age in ordinary group.The disease spectrum was analyzed in flying personnel group.The etiological characteristics were compared between two groups. Results①In ordinary group,1 265 etiological factors were found in 1 016 vertigo patients (some of them had 2 or more etiologies).The top 7 etiological factors of the vertigo patients in ordinary group were benign paroxysmal positional vertigo (BPPV)that took 32.73 % (414/1 2 6 5 ),vestibular migraine (VM),31.46% (398/1 265 ),hypertension 12.96% (164/1 265 ),diabetes 4.03% (51/1 265 ), Meniere,s disease(MD)3.87%(49/1 265),vestibular neuritis(VN)3.87%(49/1 265),and cerebral infarction 3.24%(41/1 265).1.43%(1 7/1 265)cases were unable to categorize clearly.②The patients of ordinary group,aged from 8 to 89 yrs,were categorized to <21 yrs,21-40 yrs,41-60 yrs and >60 yrs subgroups.The top 4 etiological factors for <21 yrs group were VM (43.37%),BPPV (15.79%),VN(10.53%),and sudden deafness with vertigo(10.53%);for 21-40 yrs group were VM (46.86%),BPPV(29.7 1 %),VN (5 .86%),and hypertension (4.60%);for 41-60 yrs group were BPPV(35 .1 7%),VM(3 1 .54%),hypertension(12.30%),and MD(4.73%);and for >60 yrs group were BPPV (3 1 .28%),VM (20.5 9%),hypertension (20.05%),and cerebral infraction (6.68%). Detection rate of the top 7 etiological factors had significant difference in different age groups except VN and MD (χ2=1 3 .45-5 3 .1 6 ,P<0.0 1 ).③The etiological stratification by gender showed that the ratio of male to female was 1.00︰1.57.Detection rate of VM in female was higher than that in male. Detection rate of hypertension,MD and VN in male was higher than that in female,the difference was satistically significant (χ2=3.87-8.93,P<0.05).④In flying personnel group,184 etiological factors were found in 153 vertigo patients (some of them had 2 or more etiologies).Top 3 etiological factors were motion sickness(MS)that took 1 1 .41%(21/184),VN that took 10.32%(1 9/184)and MD that took 9.78% (18/184 ).The dizziness or vertigo with no accurate etiology took 57.61 % (106/184 ).⑤The BPPV and VM detection rate in flying personnel group were less than those in ordinary group (χ2=78.34,78.7 7 ,P<0.0 1 ).The dizziness or vertigo cases with no accurate etiology and MS,MD, VN and alternobaric vertigo cetection rate in flying personnel group were higher than those in ordinary group (χ2=6 .02-645 .5 9 ,P<0.05 ). Conclusions The causes of vertigo/dizziness are complex and diverse and patients may have more than one etiology.The etiological stratification analysis for patients is conducive to accurate diagnosis and treatment.Studying the difference of etiology between flying personnel and ordinary people will contribute to exploring the pathogenesis and prevention measures in flight environment and providing proof for aeromedical assessment.

Objective To compare the various parameters of vestibular autorotation test (VAT) between the Chinese military pilots and ordinary personnel. Methods Thirty-four pilots who had passed the physical examination,including the caloric test and video-head impulse test of vestibular functions,were selected as subj ects.They received vestibular autorotation test by VAT98-3 detector that manufactured by the WSR Company of United States.The frequencies,horizontal and vertical gains and phase shift of the vestibular ocular reflex (VOR)in VAT were analyzed and compared with the corresponding parameters of 100 ordinary personnel stored in the detector. Results By comparing the measured values of 34 military pilots with 100 ordinary personnel the significant differences were found on the horizontal gain at 2.0,2.3,4.7,5.1,5.5,5.9 Hz,the horizontal phase shift at 2.0,3.9,4.7,5.1 Hz,the vertical gain at 5.5,5.9 Hz and the vertical phase shift at 2.0,3.9, 5.1 Hz (t=2.106-18.647,P<0.05).The vertical phase shifts on the frequencies of 2.3,2.7,3.1, 3.5,4.3 Hz and the asymmetry showed insignificant difference as compared with the reference values of ordinary personnel. Conclusions The military pilots show higher gains on the 2.0 and 2 .3 Hz VAT than the ordinary personnel and the gain is close to 1 ,but on 4.7 ,5 .1 ,5 .5 ,and 5 .9 Hz.The differences should be considered in the evaluation of vestibular functions for military pilots.The aeromedical assessment should take the norm of military pilot as the reference.

Objective To obtain the detection method and reference constants of cervical vestibular evoked myogenic potential (cVEMP ) and ocular vestibular evoked myogenic potential (oVEMP)in military pilots and to provide reference basis for evaluating pilot,s otolith function in aeromedical assessment. Methods Thirty-three (6 6 ears )healthy male active duty fighter pilots were selected as study subj ects.They were between the age of 25 to 42 years old (30.3 ± 4.8 years). cVEMP and oVEMP were induced unilaterally by means of 500 Hz air-conducted tone burst stimulation.The VEMPs threshold of each ear was examined and the reference range of amplitude, latency and wave interval were calculated. Results The composite wave of cVEMP and oVEMP was observed in 33 pilots.The evoked rate was 100%.The latency of p13 and n23,p13-n23 interval,peak-to-peak p1 3-n2 3 amplitude and asymmetry ratio of cVEMP in these pilots were (1 3 .94 ± 1 .5 9 )ms, (20.95±1.59)ms,(7.01 ± 1.34)ms,(224.70 ±66.15)μV,(0.1 1±0.10).The amplitude had slight difference between the ears while the cVEMP p1 3 latency,n23 latency and wave interval showed very small difference between the ears.The latency of N1 and P1 ,N1-P1 interval,peak-to-peak N1-P1 amplitude and asymmetry ratio of oVEMP in the pilots was (1 1 .1 ± 0.9 9 )ms,(1 5 .41 ± 0.85 )ms, (4.31±0.84)ms,(2.23±0.59)μV,(0.10 ±0.08)respectively.The amplitude of oVEMP,latency of N1 ,latency and wave interval of P1 showed unobvious difference between left and right ears. Conclusions This study has established the conventional detection methods and constants of cVEMP and oVEMP of military pilots and these provide the obj ective reference to evaluate the functions of utricle and sacculus in aeromedical assessment.

Objective To compare the etiology of vertigo patients between flying personnel group and ordinary group and to provide evidence for the accurate diagnosis of vertigo or dizziness and the aeromedical assessment. Methods One thousand and sixteen ordinary vertigo patients,who were diagnosed by the Vertigo Center of Former Air Force General Hospital of PLA in the period from January 2017 to April 2018,were assigned to ordinary group.One hundred and fifty-three vertigo inpatients and outpatients of flying personnel,who were diagnosed by the hospital in the period from September 1984 to Augut 2018,were selected as flying personnel group.The etiological stratification analysis was conducted upon the gender and age in ordinary group.The disease spectrum was analyzed in flying personnel group.The etiological characteristics were compared between two groups. Results①In ordinary group,1 265 etiological factors were found in 1 016 vertigo patients (some of them had 2 or more etiologies).The top 7 etiological factors of the vertigo patients in ordinary group were benign paroxysmal positional vertigo (BPPV)that took 32.73 % (414/1 2 6 5 ),vestibular migraine (VM),31.46% (398/1 265 ),hypertension 12.96% (164/1 265 ),diabetes 4.03% (51/1 265 ), Meniere,s disease(MD)3.87%(49/1 265),vestibular neuritis(VN)3.87%(49/1 265),and cerebral infarction 3.24%(41/1 265).1.43%(1 7/1 265)cases were unable to categorize clearly.②The patients of ordinary group,aged from 8 to 89 yrs,were categorized to <21 yrs,21-40 yrs,41-60 yrs and >60 yrs subgroups.The top 4 etiological factors for <21 yrs group were VM (43.37%),BPPV (15.79%),VN(10.53%),and sudden deafness with vertigo(10.53%);for 21-40 yrs group were VM (46.86%),BPPV(29.7 1 %),VN (5 .86%),and hypertension (4.60%);for 41-60 yrs group were BPPV(35 .1 7%),VM(3 1 .54%),hypertension(12.30%),and MD(4.73%);and for >60 yrs group were BPPV (3 1 .28%),VM (20.5 9%),hypertension (20.05%),and cerebral infraction (6.68%). Detection rate of the top 7 etiological factors had significant difference in different age groups except VN and MD (χ2=1 3 .45-5 3 .1 6 ,P<0.0 1 ).③The etiological stratification by gender showed that the ratio of male to female was 1.00︰1.57.Detection rate of VM in female was higher than that in male. Detection rate of hypertension,MD and VN in male was higher than that in female,the difference was satistically significant (χ2=3.87-8.93,P<0.05).④In flying personnel group,184 etiological factors were found in 153 vertigo patients (some of them had 2 or more etiologies).Top 3 etiological factors were motion sickness(MS)that took 1 1 .41%(21/184),VN that took 10.32%(1 9/184)and MD that took 9.78% (18/184 ).The dizziness or vertigo with no accurate etiology took 57.61 % (106/184 ).⑤The BPPV and VM detection rate in flying personnel group were less than those in ordinary group (χ2=78.34,78.7 7 ,P<0.0 1 ).The dizziness or vertigo cases with no accurate etiology and MS,MD, VN and alternobaric vertigo cetection rate in flying personnel group were higher than those in ordinary group (χ2=6 .02-645 .5 9 ,P<0.05 ). Conclusions The causes of vertigo/dizziness are complex and diverse and patients may have more than one etiology.The etiological stratification analysis for patients is conducive to accurate diagnosis and treatment.Studying the difference of etiology between flying personnel and ordinary people will contribute to exploring the pathogenesis and prevention measures in flight environment and providing proof for aeromedical assessment.

Objective To compare the various parameters of vestibular autorotation test (VAT) between the Chinese military pilots and ordinary personnel. Methods Thirty-four pilots who had passed the physical examination,including the caloric test and video-head impulse test of vestibular functions,were selected as subj ects.They received vestibular autorotation test by VAT98-3 detector that manufactured by the WSR Company of United States.The frequencies,horizontal and vertical gains and phase shift of the vestibular ocular reflex (VOR)in VAT were analyzed and compared with the corresponding parameters of 100 ordinary personnel stored in the detector. Results By comparing the measured values of 34 military pilots with 100 ordinary personnel the significant differences were found on the horizontal gain at 2.0,2.3,4.7,5.1,5.5,5.9 Hz,the horizontal phase shift at 2.0,3.9,4.7,5.1 Hz,the vertical gain at 5.5,5.9 Hz and the vertical phase shift at 2.0,3.9, 5.1 Hz (t=2.106-18.647,P<0.05).The vertical phase shifts on the frequencies of 2.3,2.7,3.1, 3.5,4.3 Hz and the asymmetry showed insignificant difference as compared with the reference values of ordinary personnel. Conclusions The military pilots show higher gains on the 2.0 and 2 .3 Hz VAT than the ordinary personnel and the gain is close to 1 ,but on 4.7 ,5 .1 ,5 .5 ,and 5 .9 Hz.The differences should be considered in the evaluation of vestibular functions for military pilots.The aeromedical assessment should take the norm of military pilot as the reference.

Objective To obtain the detection method and reference constants of cervical vestibular evoked myogenic potential (cVEMP ) and ocular vestibular evoked myogenic potential (oVEMP)in military pilots and to provide reference basis for evaluating pilot,s otolith function in aeromedical assessment. Methods Thirty-three (6 6 ears )healthy male active duty fighter pilots were selected as study subj ects.They were between the age of 25 to 42 years old (30.3 ± 4.8 years). cVEMP and oVEMP were induced unilaterally by means of 500 Hz air-conducted tone burst stimulation.The VEMPs threshold of each ear was examined and the reference range of amplitude, latency and wave interval were calculated. Results The composite wave of cVEMP and oVEMP was observed in 33 pilots.The evoked rate was 100%.The latency of p13 and n23,p13-n23 interval,peak-to-peak p1 3-n2 3 amplitude and asymmetry ratio of cVEMP in these pilots were (1 3 .94 ± 1 .5 9 )ms, (20.95±1.59)ms,(7.01 ± 1.34)ms,(224.70 ±66.15)μV,(0.1 1±0.10).The amplitude had slight difference between the ears while the cVEMP p1 3 latency,n23 latency and wave interval showed very small difference between the ears.The latency of N1 and P1 ,N1-P1 interval,peak-to-peak N1-P1 amplitude and asymmetry ratio of oVEMP in the pilots was (1 1 .1 ± 0.9 9 )ms,(1 5 .41 ± 0.85 )ms, (4.31±0.84)ms,(2.23±0.59)μV,(0.10 ±0.08)respectively.The amplitude of oVEMP,latency of N1 ,latency and wave interval of P1 showed unobvious difference between left and right ears. Conclusions This study has established the conventional detection methods and constants of cVEMP and oVEMP of military pilots and these provide the obj ective reference to evaluate the functions of utricle and sacculus in aeromedical assessment.

Objective To investigate the incidence rate of aerodontalgia in fighter pilots and analyze the related factors . Methods The cross-section study was used . The invasion of aerodontalgia was obtained upon a questionnaire survey from 192 fighter pilots , including the occurrence time ,degree ,and location and the incidence rate was calculated .The flying hours and the dental disease were compared between the pilots with and without aerodontalgia . Results The incidence rate of aerodontalgia in fighter pilots was 4 .17% (8/192) .In 8 aerodontalgia cases 7 pilots had dental disease .But in 184 pilots who felt free of aerodontalgia ,53 pilots (28 .80% ) were diagnosed as dental disease .There were significant difference between the incidence rates (χ2＝ 109 .634 , P＜0 .01) .In 8 pilots with aerodontalgia ,5 cases had toothache during taking-off and 3 landing .The flying altitude was 500-1 000 m .Two of 8 aerodontalgia cases appeared the toothache on maxillary teeth and jaw ,5 on lower jaw and 1 on maxillary teeth .There was no significant difference among them (P＞0 .05) .The average flying hours of 8 pilots with aerodontalgia were (2 425 .00 ± 1 445 .93) h while the average flying hours of 184 pilots without aerodontalgia was (1 703 .56 ± 1 331 .08) h .There was no significant difference between them (P＞0 .05) . Conclusions The incidence rate of aerodontalgia was higher in the fighter pilots with dental disease .But the incidence rate has no correlation to the location of toothache and flying hours .It is suggested that pilots should conduct oral examinations every 6-12 months in order to detect and treat dental diseases in time .

Objective To investigate the incidence rate of aerodontalgia in fighter pilots and analyze the related factors . Methods The cross-section study was used . The invasion of aerodontalgia was obtained upon a questionnaire survey from 192 fighter pilots , including the occurrence time ,degree ,and location and the incidence rate was calculated .The flying hours and the dental disease were compared between the pilots with and without aerodontalgia . Results The incidence rate of aerodontalgia in fighter pilots was 4 .17% (8/192) .In 8 aerodontalgia cases 7 pilots had dental disease .But in 184 pilots who felt free of aerodontalgia ,53 pilots (28 .80% ) were diagnosed as dental disease .There were significant difference between the incidence rates (χ2＝ 109 .634 , P＜0 .01) .In 8 pilots with aerodontalgia ,5 cases had toothache during taking-off and 3 landing .The flying altitude was 500-1 000 m .Two of 8 aerodontalgia cases appeared the toothache on maxillary teeth and jaw ,5 on lower jaw and 1 on maxillary teeth .There was no significant difference among them (P＞0 .05) .The average flying hours of 8 pilots with aerodontalgia were (2 425 .00 ± 1 445 .93) h while the average flying hours of 184 pilots without aerodontalgia was (1 703 .56 ± 1 331 .08) h .There was no significant difference between them (P＞0 .05) . Conclusions The incidence rate of aerodontalgia was higher in the fighter pilots with dental disease .But the incidence rate has no correlation to the location of toothache and flying hours .It is suggested that pilots should conduct oral examinations every 6-12 months in order to detect and treat dental diseases in time .

Objective:To compare the therapeutic efficacy and the recurrence rate between the simple repositioning method and the reposition manoeuvre plus medication in the treatment of horizontal semicircular canal otolith benign paroxysmal positional vertigo (HSC-BPPV). Method:Sixty-two patients diagnosed with otolith HSC-BPPV by roll maneuver test were randomly divided into canalith repositioning group (32 patients) and reposition plus drug treatment group (30 patients). Patients in the canalith repositioning group were treated only with Barbecue reposition maneuver; patients in the reposition plus drug treatment group were treated firstly with Barbecue reposition maneuver and then were given Alprostadil, Cinepazide and Betahistine drug treatment. Both groups were evaluated after 7 days and 28 days treatment, and the recurrence rate was analyzed after 3 months. Result:After 7 days of the treatment , the recovery rate of the two groups was 62.5% and 73.3%, respectively. There's no significant difference between the two groups. However, the total effective power of the reposition plus drug treatment group was 96.7%, which was significantly higher than that of the canalith repositioning group (75.0%) (χ²=5.858, P<0.05). There were 8 patients in the canalith repositioning group showed changes of BBPV types after treatment, while only 1 patient in the reposition plus drug treatment group showed lesion changes. The difference was statistically significant (χ²=4.061, P<0.05). After 28 days of the treatment, the recovery rate and the total effective power of the two groups was 100%, respectively. There is no statistical difference in the total effective rate between the two groups. After 3 months follow-up, 2 patients in the canalith repositioning group (6.25%) and in the reposition plus drug treatment group (6.67%) showed BBPV recurrence, and no significant difference in the recurrence rate was found between the two groups (P>0.05). Conclusion:The repositioning maneuver is the preferred method for treating HSC BPPV. Canalith reposition maneuver plus medication has no obvious effect on the recovery rate and the recurrence rate, it only increases the effective rate and reduces the changes of the BBPV types.

Objective To compare the ear baric function of helicopter pilots and fighter pilots and to investigate the aeromedical support on helicopter pilots' ear baric function.Methods One hundred and thirty helicopter pilots and 90 fighter pilots were inquired about their health history and examined by electric otoscopy (EOS),pure tone audiometry (PTA),acoustic immitance measurement (AIM),rhinoscopy (RS) and nasal endoscopy (NES).Those who were without contraindication to hypobaric chamber test (HCT) were subjected to HCT as follows:①both helicopter and fighter pilots were asked to sit in the chamber and climbed up to 4000 m with the velocity of 15-20 m/s,remained for 5 min and then declined to ground level with the velocity of 5 m/s;②fighter pilots were climbed to 4 000 m with the velocity of 20-30 m/s,stayed for 5 min and declined to the ground level with the velocity of 20-25 m/s.After HCT,they were re-examined by EOS,PTA and AIM.The incidence of ear baric dysfunction (EBDF) was compared between helicopter and fighter pilots.Results ①One helicopter pilot did not undergo HCT due to cold-induced grade Ⅱ eardrum congestion diagnosed by EOS,mild conductive hearing loss by PTA and C-shaped curve by AIM.②The incidence of EBDF was 6.20％ in helicopter pilots when they were declining with slow rate (5 m/s),significantly higher than that in fighter pilots (0.00％) (x2 =4.16,P＜0.05).③As with fast decline (20-25 m/s) the incidence of EBDF was 7.78％ in fighter pilots and which was insignificant with that in the helicopter pilots with slow declining rate (x2 =0.21,P＞0.05).Conclusions It should take different climbing and descending rates in the HCT ear baric function evaluation or aeromedical training for different aircraft pilots.