scholarly journals Vestibular neuronitis

2021 ◽  
pp. 31-36
Author(s):  
V. A. Parfenov
Keyword(s):  
Clinical Picture ◽  
Correct Diagnosis ◽  
Vestibular Function ◽  
Semicircular Canals ◽  
Vestibular Nerve ◽  
Vestibular Compensation ◽  
Vertebrobasilar Insufficiency ◽  
Educational Work ◽  
Vestibular Neuronitis ◽  
Simplex Virus

Vestibular neuronitis occurs as a result of damage to the vestibular nerve and is manifested by a sudden and prolonged attack of vestibular vertigo, accompanied by nausea, vomiting and imbalance. Questions of etiology, pathogenesis, clinical picture, diagnosis and treatment of VN are discussed. The disease is associated with selective inflammation (viral or infectious-allergic genesis) of the vestibular nerve. The role of herpes simplex virus type 1 is confirmed by cases of herpetic encephalitis in VN. In 2020, cases of VN development in patients with COVID-19 are described. VN usually affects the upper branch of the vestibular nerve, which innervates the horizontal and anterior semicircular canals. The duration of vertigo with VN ranges from several hours to several days. The timing of the restoration of vestibular function depends on the degree of damage to the vestibular nerve, the speed of central vestibular compensation and the patient’s performance of vestibular gymnastics. Some patients, months and even years after VN, experience significant instability. The diagnosis of VL is based on the clinical picture of the disease, the results of an otoneurological examination, and the exclusion of other diseases. VN treatment is aimed at reducing dizziness, nausea and vomiting and accelerating vestibular compensation. In our country VN is rarely diagnosed, which is associated with poor awareness of doctors about this disease. The article presents the observation of a 46-year-old patient with VN, who was mistakenly diagnosed with vertebrobasilar insufficiency, which contributed to the patient’s long-term disability. Establishing the correct diagnosis, educational work with the patient, conducting vestibular gymnastics led to an improvement in the condition, regression of instability. The issues of the effectiveness of vestibular gymnastics, the use of betahistine to accelerate the recovery of patients with VN are discussed.

Evaluation of Vertical Semicircular Canal Function in Patients With Vestibular Schwannoma

2018 ◽  
Vol 128 (2) ◽  
pp. 113-120 ◽  
Author(s):  
Keishi Fujiwara ◽  
Hiroko Yanagi ◽  
Shinya Morita ◽  
Kimiko Hoshino ◽  
Atsushi Fukuda ◽  
...  
Keyword(s):  
Vestibular Schwannoma ◽  
Semicircular Canal ◽  
Vestibular Function ◽  
Semicircular Canals ◽  
Vestibular Nerve ◽  
Head Impulse Test ◽  
Posterior Semicircular Canal ◽  
Vestibulo Ocular Reflex ◽  
Anterior Semicircular Canal ◽  
Vertical Semicircular Canal

Objectives: The aim of this study was to investigate vertical semicircular canal function in patients with vestibular schwannoma (VS) by video head impulse test (vHIT). Methods: Fifteen patients with VS who had not received any treatment, including surgery or stereotactic radiotherapy, before vHIT examination were enrolled. Vestibulo-ocular reflex gain and catch-up saccade in vHIT were evaluated. Results: Dysfunction of anterior and posterior semicircular canals was detected by vHIT in 26.7% and 60.0%, respectively. Six patients (40.0%) demonstrated abnormalities referable to both vestibular nerve divisions. Abnormalities referable to the superior vestibular nerve were identified in 3 patients (20.0%), while 3 patients (20.0%) demonstrated a pattern indicative of inferior vestibular nerve involvement. Anterior semicircular canal vHIT produced fewer abnormalities than did either horizontal or posterior semicircular canal vHIT. Conclusions: Dysfunction of the semicircular canals, including the vertical canals, in patients with VS was detected by vHIT. The anterior semicircular canal was less frequently involved than the horizontal or posterior semicircular canal. The examination of the vertical canals by vHIT is useful in the evaluation of vestibular function in patients with VS.

Horizontal Vestibuloocular Reflex Evoked by High-Acceleration Rotations in the Squirrel Monkey. II. Responses After Canal Plugging

1999 ◽  
Vol 82 (3) ◽  
pp. 1271-1285 ◽  
Author(s):  
David M. Lasker ◽  
Douglas D. Backous ◽  
Anna Lysakowski ◽  
Griffin L. Davis ◽  
Lloyd B. Minor
Keyword(s):  
High Frequency ◽  
Peak Velocity ◽  
Vestibular Function ◽  
Semicircular Canals ◽  
Vestibuloocular Reflex ◽  
Half Cycle ◽  
High Acceleration ◽  
Linear And Nonlinear ◽  
Residual Response ◽  
Sinusoidal Rotations

The horizontal angular vestibuloocular reflex (VOR) evoked by high-frequency, high-acceleration rotations was studied in four squirrel monkeys after unilateral plugging of the three semicircular canals. During the period (1–4 days) that animals were kept in darkness after plugging, the gain during steps of acceleration (3,000°/s2, peak velocity = 150°/s) was 0.61 ± 0.14 (mean ± SD) for contralesional rotations and 0.33 ± 0.03 for ipsilesional rotations. Within 18–24 h after animals were returned to light, the VOR gain for contralesional rotations increased to 0.88 ± 0.05, whereas there was only a slight increase in the gain for ipsilesional rotations to 0.37 ± 0.07. A symmetrical increase in the gain measured at the plateau of head velocity was noted after animals were returned to light. The latency of the VOR was 8.2 ± 0.4 ms for ipsilesional and 7.1 ± 0.3 ms for contralesional rotations. The VOR evoked by sinusoidal rotations of 0.5–15 Hz, ±20°/s had no significant half-cycle asymmetries. The recovery of gain for these responses after plugging was greater at lower than at higher frequencies. Responses to rotations at higher velocities for frequencies ≥4 Hz showed an increase in contralesional half-cycle gain, whereas ipsilesional half-cycle gain was unchanged. A residual response that appeared to be canal and not otolith mediated was noted after plugging of all six semicircular canals. This response increased with frequency to reach a gain of 0.23 ± 0.03 at 15 Hz, resembling that predicted based on a reduction of the dominant time constant of the canal to 32 ms after plugging. A model incorporating linear and nonlinear pathways was used to simulate the data. The coefficients of this model were determined from data in animals with intact vestibular function. Selective increases in the gain for the linear and nonlinear pathways predicted the changes in recovery observed after canal plugging. An increase in gain of the linear pathway accounted for the recovery in VOR gain for both responses at the velocity plateau of the steps of acceleration and for the sinusoidal rotations at lower peak velocities. The increase in gain for contralesional responses to steps of acceleration and sinusoidal rotations at higher frequencies and velocities was due to an increase in the gain of the nonlinear pathway. This pathway was driven into inhibitory cutoff at low velocities and therefore made no contribution for rotations toward the ipsilesional side.

scholarly journals Directional preference of otolith-related neurons in vestibular nucleus

2020 ◽  
Author(s):  
Nguyen Nguyen ◽  
Kyu-Sung Kim ◽  
Gyutae Kim
Keyword(s):  
Vestibular Nucleus ◽  
Vestibular Function ◽  
Semicircular Canals ◽  
Head Rotation ◽  
Head Movements ◽  
Neuronal Responses ◽  
Neural Communication ◽  
Neural Information ◽  
Commissural Pathway ◽  
Directional Preference

Abstract Background: Due to the paired structure of two labyrinths, their neural communication is conducted through the interconnected commissural pathway. Using the tight link, the neural responding characteristics are formed in vestibular nucleus, and these responses are initially generated by the mechanical movement of the hair cells in the semicircular canals and otoliths. Although the mechanism to describe the neuronal responses to the head movements was evident, few direct experimental data were provided, especially the directional preference of otolith-related neurons as one of critical responses to elucidate the function of the neurons in vestibular nucleus (VN). Experimental Approach: The directional preference of otolith-related neurons was investigated in VN. Also, a chemically induced unilateral labyrinthectomy (UL) was performed to identify the origin of the directional preference. For the model evaluation, static and dynamic behavioral tests were performed. Following the evaluation, an extracellular neural activity was recorded for the neuronal responses to the horizontal head rotation and the linear head translation. Results: Seventy seven neuronal activities were recorded from thirty SD rats (270-450 g, male), and total population was divided into three groups; left UL (20), sham (35), right UL (22). Based on the directional preference, two sub-groups were again classified as contra- and ipsi-preferred neurons. There was no significance in the number of those sub-groups (contra-: 15/35, 43%; ipsi-: 20/35, 57%) in the sham (p=0.155). However, more ipsi-preferred neurons (19/22, 86%) were observed after right UL (p=6.056×10-5) while left UL caused more contra-preferred neurons (13/20, 65%) (p=0.058). In particular, the convergent neurons mainly led this biased difference in the population (ipsi-: 100% after right UL & contra-: 89% after left UL) (p<0.002). Conclusion: The directional preference was evenly maintained under a normal vestibular function, and its unilateral loss biased the directional preference of the neurons, depending on the side of lesion. Moreover, the dominance of the directional preference was mainly led by the convergent neurons which had the neural information related with head rotation and linear translation.

scholarly journals A case series shows independent vestibular labyrinthine function after major surgical trauma to the human cochlea

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Stefan K. Plontke ◽  
Torsten Rahne ◽  
Ian S. Curthoys ◽  
Bo Håkansson ◽  
Laura Fröhlich
Keyword(s):  
Case Series ◽  
Vestibular Function ◽  
Semicircular Canals ◽  
Vestibular Evoked Myogenic Potentials ◽  
Head Impulse Test ◽  
Surgical Trauma ◽  
Cochlear Function ◽  
Receptor System ◽  
Tertiary Referral Center ◽  
Significant Difference

Abstract Background The receptors for hearing and balance are housed together in the labyrinth of the inner ear and share the same fluids. Surgical damage to either receptor system was widely believed to cause certain permanent loss of the receptor function of the other. That principle, however, has been called into question because there have been anecdotal reports in individual patients of at least partial preservation of cochlear function after major surgical damage to the vestibular division and vice versa. Methods We performed specific objective vestibular function tests before and after surgical trauma (partial or subtotal cochlear removal) for treatment of intracochlear tumors in 27 consecutive patients in a tertiary referral center. Vestibular function was assessed by calorics (low-frequency response of the lateral semicircular canal), vestibulo-ocular reflex by video head impulse test (vHIT) of the three semicircular canals, cervical and ocular vestibular evoked myogenic potentials (cVEMP, saccule and oVEMP, utricle). Preoperative and postoperative distributions were compared with paired t-tests. Results Here we show that there was no significant difference between pre- and post-operative measures for all tests of the five vestibular organs, and that after major surgical cochlear trauma, the vestibular receptors continue to function independently. Conclusions These surprising observations have important implications for our understanding of the function and the surgery of the peripheral auditory and vestibular system in general and open up new possibilities for the development, construction and evaluation of neural interfaces for electrical or optical stimulation of the peripheral auditory and vestibular nervous system.

Asymmetric Optokinetic Afterresponse in Patients with Vestibular Neuritis

1991 ◽  
Vol 1 (3) ◽  
pp. 279-289
Author(s):  
Krister Brantberg ◽  
Måns Magnusson
Keyword(s):  
Vestibular Function ◽  
Vestibular Compensation ◽  
Vestibular Neuritis ◽  
Spontaneous Nystagmus ◽  
Positional Nystagmus ◽  
Optokinetic Afternystagmus ◽  
Vestibular Lesion ◽  
Caloric Response

The symmetry of primary and secondary optokinetic afternystagmus (OKAN I and OKAN II, respectively) was studied in 14 patients with vestibular neuritis, as well as in 50 normals. The patients were examined at onset of symptoms and at follow-up 3 and 12 months later. At onset, OKAN was found mainly to reflect the spontaneous nystagmus. Although the spontaneous nystagmus disappeared in all patients within 3 months, both OKAN I and OKAN II was asymmetric at the 3- and 12-month check-ups. OKAN beating toward the lesioned ear was weaker than the OKAN beating toward the healthy ear. Thus, the asymmetric vestibular function was reflected not only in the OKAN I, but also by an asymmetry in OKAN II. Between the 3- and 12-month check-ups, asymmetry in OKAN declined, even among those patients who showed no improvement in caloric response during that time. The decreasing asymmetry in OKAN with time after lesion was, however, related to the disappearance of a positional nystagmus. Hence, the results may be interpreted as suggesting OKAN not only to be affected by vestibular side-difference, but also to be modified by the process responsible for vestibular compensation following a peripheral vestibular lesion.

Central Control of Postural Orientation in Flatfish

1973 ◽  
Vol 59 (2) ◽  
pp. 491-521
Author(s):  
CHRISTOPHER PLATT
Keyword(s):  
Vestibular Function ◽  
Semicircular Canals ◽  
Major Change ◽  
Differential Sensitivity ◽  
Minor Role ◽  
Otolith Organs ◽  
Supporting Evidence ◽  
Postural Change ◽  
Lateral Tilt ◽  
Functional Relations

1. Flatfish metamorphose from a larval form that swims upright like a standard fish to an adult that lies on one side, with both eyes on the upper side, having rotated posture 90° relative to gravity and the former normal posture. Adult Citharichthys stigmaeus and Hypsopsetta guttulata were used in behavioural and physiological experiments to determine whether the postural change is a peripheral or central phenomenon. 2. Cleared and sectioned specimens verify that the otolith organs, unlike the eyes, do not rotate within the skull, and so do not maintain the normal vertebrate orientation with respect to gravity. 3. Ocular compensation to lateral tilt shows that tactile cues, vision, and the semicircular canals are inadequate to produce tilt responses, but elimination of otolith function abolishes tilt responses. The major postural role of the otolith organs is not lost. 4. Selective removal of otoliths demonstrates that the flatfish utriculus has only a minor role in tilt responses, and that the sacculus-lagena is required, unlike the situation in other vertebrates. The details of the ocular compensation responses are similar to those of standard fishes. Each sacculus lies at an angle of up to 45° when in the normal position, but unilateral loss does not change the phase of the response curve, indicating that the null response is set for a non-zero value of gravitational shear, unlike the null at zero shear to the utriculus in other vertebrates. 5. Hysteresis effects suggest a differential sensitivity between tilts near the normal and the upside-down null positions. The narrowness of the effect argues against mechanical restrictions. Possibly the vertical utriculus is useful only near the normal, as an accessory organ, like the vertical lagena in other vertebrates. 6. Neural units recorded from both eighth nerve and medulla show the expected activity properties of regular and irregular rate, tonic and phasic responses to tilt, directional dependence and ‘multi-valuedness’, as in other vertebrates. No novel response types are found, nor any distinctive ‘into-level‘ types described for some vertebrates. Vibration sensitivity is associated with irregular rate, and exclusively vibration-sensitive units are apparent only in the utriculus. The shift in functional relations of the otolith organs relative to gravity is not apparently compensated for by any major change in peripheral afferent gravistatic unit properties. 7. An increasing distinction between the null at normal and the null upside-down shown by limited data on ocular compensation in three year-classes of flatfish. A central change in vestibular function is suggested that might be dependent on experience, as is gradual compensation to a vestibular lesion. 8. Since peripheral changes are not responsible for the postural change, alternative central mechanisms are proposed, including central weighting of input, recognition of a complex input pattern, and plasticity of connexions, all of which have received some supporting evidence from these results.

Acral Junctional Nevus Versus Acral Lentiginous Melanoma In Situ: A Differential Diagnosis That Should Be Based on Clinicopathologic Correlation

2011 ◽  
Vol 135 (7) ◽  
pp. 847-852
Author(s):  
Francisco Bravo Puccio ◽  
Cesar Chian
Keyword(s):  
Clinical Picture ◽  
Correct Diagnosis ◽  
Complete Excision ◽  
Acral Lentiginous Melanoma ◽  
Clear Cut ◽  
Melanoma In Situ ◽  
Histopathologic Findings ◽  
Cell Proliferations ◽  
Early Phases

Abstract Context.—Acral lentiginous melanoma is the most prevalent clinical presentation of melanoma in ethnic groups other than whites and also occurs in significant numbers in North America and Europe. Despite a clear-cut clinical picture, histologic findings seen in partial biopsies may be too subtle and deceive pathologists dealing with such cases. Objectives.—To make pathologists aware of the histologic findings during early phases of acral lentiginous melanoma (including the in situ phase), to compare those findings with what is seen in acral junctional nevus, and to highlight their similarities and differences. This review will also emphasize the important clinical and dermatoscopic findings to be considered when diagnosing acral lentiginous melanoma. Data Sources.—Review of published articles on the epidemiology; the clinical, dermatoscopic, and histopathologic findings; and the molecular biology of acral lentiginous melanoma as well as the personal experience of the authors when dealing with such cases. Conclusions.—Acral lentiginous melanoma is a clinicopathologic entity with a clear-cut clinical picture: a diameter larger than 0.7 mm; ill-defined, darkly pigmented, flat lesion with irregular borders on acral locations; and the presence of mostly single-cell proliferations of melanocytes along the dermo-epidermal junction. Along with a few additional criteria, these findings should be sufficient to allow the pathologist to make the diagnosis and to recommend complete excision. Fluent communication between clinician and pathologist will facilitate a correct diagnosis.

Comorbidity Issues and Treatment in Chronic Mental Illness

2017 ◽  
pp. 77-100
Author(s):  
Deepika Srivastav ◽  
Tej Bahadur Singh
Keyword(s):  
Clinical Picture ◽  
Correct Diagnosis ◽  
Multidisciplinary Treatment ◽  
Major Effect ◽  
Obsessive Compulsive ◽  
Treatment Need ◽  
Compulsive Disorder ◽  
Primary Disorder ◽  
Panic Symptoms ◽  
Anxiety Depression

Comorbidity refers to presence of one or more additional disorders along with a primary disorder. It affects the prognosis and course of treatment. It is often difficult for clinician to make correct diagnosis in presence of various disorders. The clinical picture of various disorders interferes with treatment process and the outcome. There are some disorders in psychiatry, known as chronic illness. These are schizophrenia, bipolar disorder and obsessive-compulsive disorder. All these three disorder have a major effect on individual's life. Anxiety, depression, substance abuse and panic symptoms are common in schizophrenia; hence the clinical picture changes frequently. While the literature suggests that presence of two or three disorders make treatment worse, hence multidisciplinary treatment need to be used.

Dizziness, Vertigo, and Syndromes of the Medulla

2014 ◽  
pp. 292-332
Author(s):  
Shirley H. Wray
Keyword(s):  
Vestibular Function ◽  
Semicircular Canals ◽  
Clear Distinction ◽  
Head Impulse Test ◽  
History Taking ◽  
Clinical Detail ◽  
Full Discussion ◽  
Diagnostic Symptoms ◽  
Inferior Olivary ◽  
Intractable Hiccups

reviews the medulla’s vestibular components (the vestibular, perihypoglossal, and inferior olivary nuclei ), and the components of the vestibular labyrinth (the semicircular canals and the otolith receptors) preparatory to a full discussion of dizziness and vertigo as diagnostic symptoms. The model used for history-taking is extensive and allows for clear distinction to be made between the two symptoms and their implications for risk of stroke. Direction- changing nystagmus as a localizing sign is discussed in depth, and provocative tests to elicit nystagmus by suppression of fixation are presented in clinical detail. The head-thrust (head impulse) test is also described as a simple way to identify a complete unilateral or bilateral loss of vestibular function at the bedside. Medullary syndromes illustrated by case studies include oculopalatal tremor, benign paroxysmal positional vertigo, upbeat and apogeotropic nystagmus, Wallenberg’s syndrome due to infarction of the medulla, and a case of intractable hiccups.

scholarly journals Disseminated Neuroblastoma in an Adult Presenting the Picture of Thrombocytopenic Purpura

Blood ◽  
1956 ◽  
Vol 11 (3) ◽  
pp. 273-278 ◽  
Author(s):  
WILLIAM N. CHRISTENSON ◽  
JOHN E. ULTMANN ◽  
STEVEN C. MOHOS
Keyword(s):  
Bone Marrow ◽  
Acute Leukemia ◽  
Idiopathic Thrombocytopenic Purpura ◽  
Clinical Picture ◽  
Correct Diagnosis ◽  
Blood Picture ◽  
Thrombocytopenic Purpura ◽  
Metastatic Lesions ◽  
Initial Symptoms ◽  
Immature Cells

Abstract A case of neuroblastoma in an adult with extensive metastatic lesions is presented. The initial symptoms and findings suggested idiopathic thrombocytopenic purpura. The blood picture and changes in the clinical picture later led to a diagnosis of acute leukemia. Autopsy disclosed the correct diagnosis, which would have been possible antemortem had the implication of pseudorosette arrangement of immature cells in the bone marrow and the possible occurrence of neuroblastoma in an adult been fully appreciated.

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