Treatment Efficacy of Various Maneuvers for Lateral Canal Benign Paroxysmal Positional Vertigo With Apogeotropic Nystagmus: A Randomized Controlled Trial

Objectives@#The aim of this study was to determine the most effective treatment approach by comparing the impacts of various otolith reduction techniques in patients with apogeotropic lateral semicircular canal benign paroxysmal positional vertigo (LC-BPPV). @*Methods@#We performed a multicenter randomized prospective study from January to December 2015, involving 72 consecutive patients with apogeotropic LC-BPPV. The patients were divided into three treatment groups: therapeutic head-shaking (group A), the Gufoni-Appiani maneuver (group B), and the cupulolith repositioning maneuver (CuRM; group C). Each group underwent evaluation and treatment up to the fourth week. Treatment success was defined as the disappearance of positional vertigo and nystagmus. @*Results@#This study included 72 patients (49 male and 23 female), with a mean (±standard deviation) age of 55.4±13.5 years. The mean duration of vertigo experienced prior to treatment was 3.9±4.4 days. The mean latency and duration of nystagmus were 2.7±3.0 seconds and 47.9±15.8 seconds, respectively. The overall treatment frequency was 2.0±0.9. The number of treatments differed significantly among the three groups (P0.05). However, CuRM was the only method with a 100% treatment success rate. @*Conclusion@#While no clear difference was observed among the three treatments for LC-BPPV, CuRM was found to be superior to the other approaches in the long term.

Effects of Intratympanic Injection of Isosorbide on the Vestibular Function of Animal Models of Endolymphatic Hydrops

Objectives@#. The aims of this study were to investigate the effects of intratympanic injections of isosorbide on vestibular function in animal models of endolymphatic hydrops and to find a new treatment option for the acute onset of vertigo in Ménière disease (MD). @*Methods@#. Seventy male guinea pigs received intratympanic injection of isosorbide (IT-ISB). The animals were divided into three study groups: control, a chronic hydrops model, and an acute hydrops model. Intracochlear drug concentrations were measured using high-performance liquid chromatography. Vestibular function was analyzed using an animal rotator test with bidirectional sinusoidal harmonic acceleration before and after IT-ISB administration. Histological changes were also investigated. @*Results@#. ISB successfully permeated the perilymph through the round window membrane (RWM) at all three concentrations (25%, 50%, and 100%). In the chronic hydrops model, while IT-ISB histologically induced a reduction of endolymphatic hydrops, vestibular function was unchanged. In the acute hydrops model, no endolymphatic hydrops was histologically observed, and vestibular symmetry was also preserved after IT-ISB. @*Conclusion@#. ISB passed through the RWM into the perilymphatic space even at lower concentrations. IT-ISB histologically reduced hydrops in the chronic model and preserved symmetrical vestibular function in the acute model. IT-ISB could be a treatment candidate for acute attacks of vertigo in MD.

Characteristics of Nystagmus during Attack of Vestibular Migraine / 대한평형의학회지

OBJECTIVES: The purpose of this study is to investigate characteristics of nystagmus during attacks of vestibular migraine (VM), and to find a distinct clinical feature compared to other migraine and peripheral vestibular disorders. METHODS: This study is a retrospective chart review of 82 patients satisfied with VM criteria, which is formulated by the new Bárány Society. Spontaneous and positional nystagmus provoked by various head positions were examined with video-nystagmography in all patients. Bithermal caloric test and cervical vestibular evoked myogenic potential test (cVEMP) were also performed. The direction and peak slow-phase velocity (SPV) of nystagmus, unilateral caloric weakness and interaural difference of cVEMP were analyzed. Control groups were lesion side in acute VN for nystagmus results and healthy side in the patients with benign paroxysmal positional vertigo of posterior semicircular canal for caloric and cVEMP results. Chi-square test and Mann-Whitney U-test were used for statistical analysis. RESULTS: During the acute attack, nystagmus was seen in 71.9% (59 of 82) of patients. Horizontal nystagmus was the predominant type. Peak SPV in VM patients was much slower than in the control group (2.37±1.73 °/sec vs. 17.05±12.69 °/sec, p<0.0001). There was no significant difference on the result of both caloric and cVEMP test, compared to those of control groups. CONCLUSION: Nystagmus with horizontal directions and low SPV was dominant form in the attack of VM. Close observation of nystagmus can be helpful to make a correct diagnosis and to understand the pathomechanism of vertigo in VM.

Efficient Utilization of Korean Medical Fungal Pathogen Resource Bank for Clinical Research / 대한의진균학회지

A “pathogen resource” contains information about pathogens (e.g., bacteria, fungi, viruses, and protozoa) and microbial derivatives (e.g., DNA, RNA, plasmid, clone, and cDNA). Pathogen resources are important for their potential use in healthcare research because they contain clinical and epidemiological information that is different from microbial resources. In October 2014, the “Nagoya Protocol” on access and benefit-sharing with the Convention on Biological Diversity was enacted to restrict the movement of transboundary pathogens and protect the natural pathogen resources of each country. On July 2017, the Korean Medical Fungal Pathogen Resource Bank (KMFRB) was established to secure, discover, and develop biological resources focused on medical fungi. KMFRB has since been operating under the National Culture Collection for Pathogens of the National Institute of Health based on the Act No. 13992. This report aims to provide general information regarding KMFRB and suggest efficient ways to utilize human fungal pathogen resources for clinical research.

Limitation of High Pitch Sound Perception in Nontumor Patients with Auditory Brainstem Implantation / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Auditory brainstem implantation (ABI) is another option for hearing rehabilitation in non-neurofibromatosis type 2 patients who cannot undergo cochlear implantation (CI). However, the average performance of ABI is worse than that of CI. We analyzed the psycho-electrical parameters of each electrode and psycho-acoustic response to different frequency sounds in nontumor patients with ABI. SUBJECTS AND METHOD: Sixteen patients with ABI from July 2008 to May 2013 were included in the study. They were followed up for 4 to 56 months. Among them, 12 were prelingual deaf with a narrow internal auditory canal or cochlear ossification. The remaining four were post-lingual deaf adults with severely ossified cochleae. We analyzed the electrical parameters [impedance, threshold level (T level), and dynamic range] of each of the 12 electrodes. We also evaluated the sound field pure-tone threshold, Ling 6 sound detection-identification test (Ling 6 test), and pitch ranking data of these patients. RESULTS: The impedance, T level, and dynamic range did not significantly differ among electrodes. However, the pure-tone threshold to sound field stimulation was elevated in the high tone area, where more variables were found than in the low frequency area. Patients could not identify /S/ and /Sh/ sounds in the Ling 6 test. The mean T level and the dynamic range of the three highest pitch-perceiving electrodes in each patient was higher and narrower, respectively, than those of the three lowest pitch-perceiving electrodes. CONCLUSION: The nontumor patients with ABI have difficulty perceiving high pitch sound. More sophisticated penetrating type electrodes and, if possible, bimodal stimulation with CI, could be considered.

Posttraumatic Peripheral Vertigo / 대한평형의학회지

Posttraumatic vertigo can be defined as the vertiginous disorder occurred after head and neck trauma without other pre-existing vestibular disorder. Central, peripheral, and combined deficits might cause this condition. Especially, various peripheral vestibulopathies are possible causes of posttraumatic vertigo; benign paroxysmal positional vertigo, temporal bone fracture, perilymphatic fistula, labyrinthine concussion, posttraumatic hydrops, and cervical vertigo. Since the differential diagnosis of the posttraumatic vertigo is often difficult, it is essential to acquire knowledge of their pathophysiology and clinical features. In this review, peripheral vestibulopathy as the possible causes of posttraumatic vertigo were described according to the current literature.

Identification of Vestibular Organ Originated Information on Spatial Memory in Mice / 대한평형의학회지

OBJECTIVES: We aimed to study the role of vestibular input on spatial memory performance in mice that had undergone bilateral surgical labyrinthectomy, semicircular canal (SCC) occlusion and 4G hypergravity exposure. METHODS: Twelve to 16 weeks old ICR mice (n=30) were used for the experiment. The experimental group divided into 3 groups. One group had undergone bilateral chemical labyrinthectomy, and the other group had performed SCC occlusion surgery, and the last group was exposed to 4G hypergravity for 2 weeks. The movement of mice was recorded using camera in Y maze which had 3 radial arms (35 cm long, 7 cm high, 10 cm wide). We counted the number of visiting arms and analyzed the information of arm selection using program we developed before and after procedure. RESULTS: The bilateral labyrinthectomy group which semicircular canal and otolithic function was impaired showed low behavioral performance and spacial memory. The semicircular canal occlusion with CO₂ laser group which only semicircular canal function was impaired showed no difference in performance activity and spatial memory. However the hypergravity exposure group in which only otolithic function impaired showed spatial memory function was affected but the behavioral performance was spared. The impairment of spatial memory recovered after a few days after exposure in hypergravity group. CONCLUSIONS: This spatial memory function was affected by bilateral vestibular loss. Space-related information processing seems to be determined by otolithic organ information rather than semicircular canals. Due to otolithic function impairment, spatial learning was impaired after exposure to gravity changes in animals and this impaired performance was compensated after normal gravity exposure.

Hyper-response of Cervical Vestibular Evoked Myogenic Potential in Patients with Meniere Disease: A Preliminary Study / 대한평형의학회지

OBJECTIVES: The purpose of this study is to investigate the hyper-responsiveness of cervical vestibular-evoked myogenic potential (cVEMP) in patients with Meniere disease (MD), and to compare the result of cVEMP between probable and definite MD group. METHODS: A total of 110 patients satisfied with probable MD and definite MD criteria, which is recently formulated by the Classification Committee of the Bárány Society, were included. An interpeak amplitude and interaural amplitude difference (IAD) ratio of both ears was measured. The abnormal response of ipsi-lesional cVEMP was categorized into 2 groups; hyper-response and hypo-response. Chi-square test and Mann-Whitney U-test were used for statistical analysis. RESULTS: In the probable MD and definite MD group, the mean IAD was 25.24%±17.79% and 53.82%±34.98%, respectively (p < 0.01). The abnormal response of cVEMP at the affected ear was more frequent in the definite MD group, compared to the probable MD group (32/40 vs. 13/36, p < 0.01). However, hyper-response was more frequently observed in the patients with probable MD, compared to the patients with definite MD (13/36 vs. 3/40, p < 0.01). CONCLUSION: Hyper-response of cVEMP was more frequently observed in the early probable MD patients. It might be an early sign of MD, related with the saccular hydrops, which can help the early detection and treatment.

Influence of Diazepam on Video Head Impulse Test in Patients with Acute Vestibular Neuritis: Preliminary Study / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Although video head impulse test (V-HIT) has emerged as a popular test for vestibular function, there have been no reports about the influence of benzodiazepine on the test. The aim of this study is to investigate the influence of diazepam on the V-HIT in patients with acute vestibular neuritis. SUBJECTS AND METHOD: We retrospectively analyzed charts and medical records of 10 patients diagnosed with acute vestibular neuritis. The patients repeated V-HIT before and after intravenous (IV) injection of diazepam. Gain and presence of catch-up saccade (CUS) were compared. RESULTS: Gain in the affected ear was decreased compared to that in the unaffected ear. After the injection of IV diazepam, the presence of CUS was not changed significantly. Gain of CUS in V-HIT was also unchanged both in the affected and unaffected ear after the injection of IV diazepam. CONCLUSION: The influence of IV diazepam on the gain and presence of CUS in V-HIT were insignificant, indicating that it could be considered as a useful test to evaluate vestibular function in patients treated with diazepam.

Experiemental Model for Ménière's Disease Using Surgical Ablation of Endolymphatic Sac / 대한평형의학회지

Endolymphatic hydrops is a representing pathologic finding of Ménière's disease. For the induction of endolymphatic hydrops in an animal model, surgical ablation of endolymphatic sac has been used. Although traditional model with the blockage of endolymphatic sac induced severe hydrops, it has several limitations for the study of pathophysiology of Ménière's disease. Recently, modified experimental models have been introduced, in which additional procedure was performed to induce the acute aggravation of hydrops after the surgical ablation. These new models could be helpful to elucidate the mechanism and develop a new treatment of Ménière's disease. In this review, we introduce the characteristics of animal models using surgical ablation of endolymphatic sac from the classical model to novel modified models.

Acute Vestibular Neuritis and Ramsay-Hunt Syndrome / 대한평형의학회지

Acute vestibular neuritis is the disorder characterized by acute, spontaneous vertigo with the unilateral vestibular loss. Reactivation of herpes simplex virus is considered as its cause. Its management consists of symptomatic therapy in the acute phase and following rehabilitation exercise to improve central compensation. The differential diagnosis should include central vestibular disorders mimicking peripheral vertigo. Ramsay-Hunt syndrome, which defined as a herpes zoster oticus with facial paresis, is also a disorder frequently accompanied with vestibular deficit. Combination therapy of acyclovir and corticosteroid is recommended for the treatment. In this review, diagnosis and management of the two disorders are described.

Lateral Medullary Infarction with Ipsilesional Gaze-Evoked and Head-Shaking Nystagmus / 대한평형의학회지

For differential diagnosis between vestibular neuritis and lateral medullary infarction with similar clinical features, bedside examination of nystagmus is important. We report a 45-year-old male who presented with acute vertigo for two days. He showed spontaneous right-beating nystagmus. However, left-beating nystagmus was evoked during bilateral horizontal gaze and by horizontal head oscillation. Brain MRI revealed an acute infarction in the left lateral medulla.

Isosorbide Concentration in Perilymph of the Guinea Pig After Oral Administration Versus That After Round Window Perfusion

OBJECTIVES: The aims of this study were to investigate the feasibility of isosorbide delivery into perilymph through the round window membrane (RWM), and to compare the intracochlear isosorbide concentration in perilymph after oral administration (PO) versus that after round window perfusion (RWP). METHODS: Sixteen male guinea pigs (32 ears) were used. Isosorbide, an osmotic diuretic, was administered via RWP or PO. First, to investigate the optimal perfusion time, perilymph sampling of scala tympani from the RWM was performed after RWP for 15, 30, or 60 minutes. Second, to compare the drug concentration after RWP versus that after PO, perilymph was aspirated at 3 and 6 hours after administration. Intracochlear concentration of isosorbide was analyzed by high-performance liquid chromatography coupled to refractive index detection. RESULTS: Isosorbide passed through the RWM into perilymph after RWP. After RWP for 15, 30, and 60 minutes, mean isosorbide concentrations in perilymph were 116.27+/-44.65, 245.48+/-112.84, and 279.78+/-186.32 mM, respectively. The intracochlear concentration after RWP for 30 minutes was higher than that after RWP for 15 minutes (P=0.043). At 3 and 6 hours after PO, isosorbide concentrations in perilymph were 28.88+/-4.69 and 12.67+/-2.28 mM, respectively. In contrast, the corresponding concentrations after RWP were 117.91+/-17.70 and 75.03+/-14.82 mM at 3 and 6 hours, respectively. Isosorbide concentrations in perilymph following RWP were significantly higher than those following PO at both 3 and 6 hours (P=0.025 and P=0.034, respectively). CONCLUSION: Isosorbide can rapidly pass through the RWM after RWP in guinea pigs, and 30 minutes of perfusion is considered to be appropriate. In addition, over a 6-hour period, RWP can deliver higher concentrations of isosorbide into perilymph than those achieved with PO.

Comparison of Time and Cost between Sequential and Simultaneous Bilateral Cochlear Implants / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Purpose of this study is to compare the cost-effectiveness between sequential (SeqBCI) and simultaneous bilateral cochlear implantations (SimBCI). SUBJECTS AND METHOD: This is a retrospective study of 15 patients who underwent bilateral cochlear implantations at a tertiary care facility. Nine patients with SimBCI and six with SeqBCI were included. Operation time, anesthesia time, expenses for preoperative evaluation, hospitalization time, hospital expenses and postoperative expenses were investigated. RESULTS: The 1st, 2nd and cumulative operation time for the SeqBCI group were 181, 120 and 301 minutes, respectively, on the average. The 1st, 2nd and cumulative anesthesia time were 212, 162 and 373 minutes, respectively. The 1st, 2nd and cumulative expenses for preoperative evaluation were 1074754, 280118 and 1354872 won, respectively. The 1st, 2nd and total hospitalization time were 6.2, 4.2 and 10.4 days, respectively. The 1st, 2nd and cumulative hospital expenses were 24082713, 24158366 and 48176734 won, respectively. The 1st, 2nd and cumulative postoperative expenses were 447830, 551778 and 999608 won, respectively. For the SimBCI group, the operation time, anesthesia time, expenses for evaluation, hospitalization time, hospital expenses and postoperative expenses were 246, 280 minutes, 1396793 won, 6.2 days, 46073011 and 816121 won, respectively. On the whole, anesthesia time, hospitalization time and postoperative expenses of the SimBCI group were less than those of the SeqBCI group (p=0.01, 0.02 and 0.02, respectively). The postoperative expenses of SeqBCI were the highest during the first 4 months whereas those of SimBCI were less during the same period (p=0.03). CONCLUSION: Cumulative anesthesia time, hospitalization time and postoperative cost of SimBCI were less than those of SeqBCI. Our results may be useful for counseling the timing of second CI.

Bilateral Vestibulopathy / 대한이비인후과학회지

Bilateral vestibulopathy (BV) is a clinical entity with impaired function of bilateral peripheral vestibular system, which is characterized by movement-induced postural vertigo, oscillopsia and unsteadiness of gait. The possible causes are reported including aminoglycosides, Meniere's disease and meningitis, however, cause of BV remains unclear in up to half. The diagnosis is confirmed by a combination of the vestibulo-ocular reflex tests such as a bilateral head-impulse test, the rotatory chair test and the caloric test. The treatment consists of prophylaxis of progressive vestibular loss, recovery of impaired vestibular function and promotion of central compensation or substitution with rehabilitation therapy.

Clinical Characteristics of Benign Paroxysmal Positional Vertigo of the Anterior Semicircular Canal / 대한평형의학회지

BACKGROUND AND OBJECTIVES: The aim of this study is to investigate the characteristics of anterior semicircular canal benign paroxysmal positional vertigo (BPPV). MATERIALS AND METHODS: This is a retrospective chart review of 1,150 patients who were diagnosed with BPPV at an ENT special hospital. We investigated a number of canalith repositioning procedure (CRP), canal switch and a history of recurrence or head trauma. RESULTS: Anterior semicircular canal BPPV was observed in 41 (3.5%) patients. The average number of CRPs in patients with anterior semicircular canal BPPV was 2.19, which was higher than 1.60 in those with posterior semicircular canal BPPV (p<0.0001). Canal conversion from anterior to posterior semicircular canal was found in 5 (12.1%) patients during treatment. The average number of CRPs in conversion cases was 4, which was higher than 1.94 in non-conversion cases (p=0.001). CONCLUSION: More CRPs were necessary for the treatment of anterior semicircular canal BPPV than posterior semicircular canal BPPV. Canal switch could be considered as a factor to prevent a successful treatment.

An Atypical Case of Benign Paroxysmal Positional Vertigo of the Anterior Semicircular Canal / 대한평형의학회지

Benign paroxysmal positional vertigo (BPPV) of anterior semicircular canal (ASC) is the rarest variant of BPPV, which is thought to be due to the anatomically superior position of ASC during most activities. This type of BPPV is currently diagnosed by detecting positional down-beating nystagmus in the Dix-Hallpike test. A 62-year-old female presented with positional vertigo, especially when sitting up. No nystagmus was induced by both Dix-Hallpike tests, however, positional down-beating nystagmus was observed with the left torsional component when sitting up from both Dix-Hallpike positions and supine position. After the reverse Epley maneuver, up-beating nystagmus was newly observed in the left Dix-Hallpike test, which was compatible with BPPV of the left posterior semicircular canal. This patient was thought to suffer from canalithiasis of the left ASC.