A cure for benign positional vertigo

Benign positional vertigo is a common clinical entity encountered in any dizzy clinic. It is easily diagnosed on the basis of historical information and a positive Dix-Hallpike position test. The available evidence suggests that this condition is due to involvement of the posterior semicircular canal. The pathophysiology of this condition can be explained theoretically on the basis of free-floating particles within the endolymph of the posterior semicircular canal that move under the influence of gravity with certain provocative positional changes. Based on this theoretical model, a variety of particle-repositioning manoeuvres have been developed that attempt to relocate the loose particles from the posterior semicircular canal to the utricular sac. If the particles are kept in the utricular sac for a period of 48 h by maintaining the patient in an upright position, the clinical symptoms are relieved in a high proportion of patients. If the manoeuvre is unsuccessful on a first attempt, or if the benign positional vertigo recurs at a later date, the condition can usually be relieved by a second manoeuvre. Bilateral benign positional vertigo can be treated by performing a manoeuvre on one side followed by a manoeuvre on the other side at a later date. On occasion, posterior canal benign positional vertigo is converted to horizontal canal benign positional vertigo, but this subsides readily within the 48-h post-manoeuvre period.     

Vertigo and migraine

Vertigo consists of a variety of syndromes and can be due to many etiologies. One of these causes is migraine, which in our experience is often overlooked, although migrainous vertigo is well known in the literature. Vertigo in migraine can occur as aura or during the headache phase, or independent of the attacks as aura without headache. The aim of this retrospective study was to analyze cases with vertigo and migraine: 23 (8%) of 298 patients with migraine examined in a neurological outpatient department also had rotational vertigo. 48% of these patients had vertigo independent from typical migraine headache. Two types of vertigo were found: permanent vertigo, and vertigo with the characteristics of paroxysmal positional vertigo. 57% of the vertiginous attacks lasted hours, 26% even days, and 17% minutes. Most of the patients had several attacks of vertigo, some involving up to 30 episodes. To recognize migraine as a cause of vertigo has therapeutic implications. Most of our patients with vertigo and migraine showed a good response to antimigraine therapy.     

Vertigo

Vertigo is a subtype of dizziness, which results from an imbalance within the vestibular system. This seminar focuses on three common presentations of vertigo: prolonged spontaneous vertigo, recurrent attacks of vertigo, and positional vertigo. The patient's history is usually the key to differentiation of peripheral and central causes of vertigo. The most common cause of vertigo, benign paroxysmal positional vertigo, can be cured with a simple positional manoeuvre. Other common causes of vertigo include vestibular neuritis, Ménière's syndrome, migraine, and vertebrobasilar insufficiency. Treatment should be directed at the underlying cause whenever possible, but antivertiginous and antiemetic drugs can suppress symptoms when a specific cause cannot be found. These drugs are generally not indicated for long-term daily use, however, since they may interfere with the normal compensation process.     

Endolymphatic sac enhancement surgery in elderly patients with Ménière's disease

Ménière's disease is a pathologic condition of the inner ear that is characterized by vertigo, tinnitus and a progressive loss of hearing. When Ménière's disease is unresponsive to medical treatment and when destructive surgery is not advisable, patients, particularly the elderly, often benefit from endolymphatic sac enhancement, a conservative, nondestructive surgical procedure. We evaluated the outcomes of 62 such patients, aged 65 years and older, who underwent a total of 78 endolymphatic sac enhancements. We assessed their response to surgery by means of a questionnaire, which classified pre- and post-surgical data according to criteria established by the American Academy of Otolaryngology-Head and Neck Surgery. Of the 27 patients who returned questionnaires, 23 reported significant alleviation of vertigo symptoms and 19 said their hearing ability had either improved or was maintained at presurgical levels. Endolymphatic sac enhancement resulted in no mortality, and morbidity was documented in only one patient. We conclude that endolymphatic sac enhancement is a safe and viable treatment for elderly patients with Ménière's disease that is refractory to medical therapy.     

A prearranged mentorship program: can it work long distance?

The results of a series of scanning electron microscopical studies were used to construct a model for the vascular pathways in the inner ear. Corrosion cast preparations of the vessels of the inner ear of the adult rat were used in this study. The inner ear is, like a hand, an end organ containing four sense organs (cochlea, saccule, utricle and the cristae ampullaris). All these specific inner ear structures have their own vascular supply. We have developed a blood flow diagram of the inner ear. This model was used for a classification of different types of ischemia in the inner ear and forms a concept for some forms of sensorineural hearing loss and vertigo. Four types of inner ear ischemia are proposed. In type I (a or b) of inner ear ischemia only the vessels of the cochlea are involved resulting in two types of hearing loss without vertigo. Type II is characterized by ischemia of a part of the cochlea and a part of the vestibular system. In type III (a or b) only the vestibular system is involved, while in type IV no blood circulation will be present in the inner ear resulting in total deafness and severe vertigo. Inner ear partition at ultramicroscopical level of these structures may be possible in the future and new imaging techniques will probably support the vascular schematic model presented in this study.     

Antigen removal after inoculation into the endolymphatic sac of immunized guinea pigs

Antigen removal in the endolymphatic sac (ES) was immunohistochemically examined. Forty-five adult female Hartley guinea pigs were used in this study. After keyhole limpet hemocyanin (KLH) systemic immunization, KLH was directly injected into the lumen of the right ES. The presence of KLH was detected in histological sections using immunohistochemistry. After KLH challenge into endolymphatic sac lumen, high concentrations of KLH were diffusely found within phagocytes in the endolymphatic lumen and peri-saccular tissue on day 2. After day 14, KLH disappeared from the immunized inner ear. The above results suggest that KLH is removed from the inner ear by diffusion through the endolymphatic epithelial cells which have altered permeability or by phagocytosis of the phagocytic cells. No KLH was observed in the left endolymphatic sac and bilateral cochlea as well as vestibular organ during 5 months of follow up. This study showed that the endolymphatic sac is capable of appropriately trapping macromolecule, KLH antigen (molecular weight: about 400 KDa), and removing antigens quickly from the inner ear.     

Cocaine impairs follicular phase pulsatile gonadotropin secretion in rhesus monkeys

BACKGROUND: Ménière's disease is a medical condition that involves hearing loss, tinnitus and attacks of vertigo. The attacks can be severely disabling with nausea, dizziness, and aural sensations. METHOD: Three scales assessing the correlates of vertigo attacks in Ménière's disease were developed and completed by 514 subjects diagnosed with the disease. The three scales measured were somatic sensations (SOM), psychological state (PSYCHOL), and situational characteristics (SIT) associated with an attack. RESULTS: Psychometric properties of the three scales were investigated showing Cronbach's alphas of 0.76, 0.80, and 0.62 for the three scales respectively. The results on the scales were related to disease progression. Principal components factor analyses showed that the SOM scale could be divided into two subscales: dizziness/vertigo/anxiety and sensations in the ear. The PSYCHOL scale showed an energy/awareness factor and a negative emotional state factor. The SIT scale, finally, showed two factors: environmental disturbances and stressful conditions. CONCLUSIONS: Knowledge of somatic, psychological and situational premonitory characteristics of attacks in Ménière's disease could lead to improved therapy and counselling.     

Intravenous gentamicin therapy in bilateral Menière disease

BACKGROUND: The treatment of severe forms of bilateral Menière's disease remains an especially challenging task. Similar problems also occur in debilitating Menière's disease in the only hearing ear. The intramuscular titration therapy with streptomycin has been the means of choice since 1984 to minimize the risk of total hearing loss in cases of severe bilateral disease. METHOD: Since 1989 we have treated six out of 21 cases of bilateral Menière's disease by intravenous application of 2 x 120 mg gentamicin in Ringer's solution for several days. Additionally we reported on two cases in 1988. Only minor amounts of gentamicin were applied to sedate the function of both vestibular organs while avoiding damage to the cochlea. RESULTS: In two cases hearing approved approximately about 10 dB, in two cases hearing remained stable, and in two cases hearing worsened about 10 dB. Five of six patients showed minor excitability in caloric tests on both sides, they did not complain of vertigo attacks one to five years after therapy. CONCLUSION: Given that only very small amounts of gentamicin are applied to sedate the function of the vestibular organ while causing almost no damage to the cochlea, this method seems to be an excellent means for treatment of bilateral Menière's disease. Patients do not experience severe problems with equilibrium afterwards, and the treatment can be repeated as often as necessary.     

Benign paroxysmal vertigo of childhood

Thirty-three cases of benign paroxysmal vertigo in childhood have been seen at our institution since the disorder was recognized ten years ago. Progression from paroxysmal torticollis of infancy to paroxysmal vertigo of childhood is documented. Ear infections and allergy appeared causative in a few, but not most, of the cases. The most important consideration for the pediatrician is to rule out epilepsy and brain tumor. Parents should be reassured that the condition is benign, and that the attacks will cease in a few months or years.     

Surgery for intractable vertigo: Chiang Mai experience

If medical therapy fails (6-12 months or more), careful consideration of surgical therapy should be followed with; the patient's hearing, severity of symptoms, age, and occupation. Cochleosacculotomy is reserved for elderly Meniere's patients with poor health, poor hearing and good vestibular function. Endolymphatic sac shunt should be considered as the first procedure for disabled Meniere's patients with aidable hearing and may also be used in those patients with bilateral Meniere's disease. Retrolabyrinthine vestibular nerve section (RLVNS) is indicated for patients with disabling vertigo and normal or aidable hearing. It could be done for all peripheral vertigo and for failed endolymphatic sac procedure. A destructive procedure, such as labyrinthectomy, should be a procedure of choice in a patient who presents with peripheral incapacitating vertigo and nonserviceable hearing loss in the solely affected ear. Again, patients with failed cochleosacculotomy, endolymphatic shunt then go on to receive either labyrinthectomy or RLVNS, based on residual hearing. To obtain a satisfactory surgical result, the surgeon must be precise in selecting the patient with the right disease at the right time.     

Attenuation of contractile responses to sympathetic co-transmitters in veins from subjects with essential hypertension

The aim of this questionnaire study was to investigate the impact of the symptoms in Meniere's disease on the daily life of patients and to analyse the relationships between the cardinal symptoms and environmental, emotional and activity factors. The study comprised 514 patients, recruited from two different sources. The results showed that vertigo, hearing impairment and tinnitus had a strong negative influence on the daily life of patients. Seventy-five percent of the subjects avoided certain everyday activities or situations because of the disease. However, the correlation between discomfort and reported satisfaction with life was moderate. Most of the subjects experienced premonitory symptoms of the attacks and 80% reported relations between external factors and vertigo attacks.     

Nutritional supplementation of disadvantaged elementary-school children

This paper describes a method of endolymphatic sac decompression and drainage. The method emphasizes widely exposing dura, avoiding skeletonization of the posterior semicircular canal and draining the sac via a T tube. The results of this procedure in 75 patients, including statistics in 46 ears are discussed. In patients with unilateral disease good results were obtained in control of vertigo in 94 percent of patients and significant improvement in cochlear function in over 30 percent.     

Histopathological findings in clinical gentamicin ototoxicity

The temporal bone histopathological findings in a case of gentamicin sulfate-induced hearing loss and vertigo in an anephric patient undergoing hemodialysis are presented. A study of the sensory neuroepithelium of the cristae and maculae disclosed the presence of vacuoles with clubbing of the sensory cells. In the cochlea, loss of the innermost row of outer hair cells in the basal turn was the most prominent feature. These findings are discussed in light of reports of similar morphological changes in laboratory studies of gentamicin ototoxicity.     

Favourite objects of autistic children

This paper presents a lumped-parameter model that stimulates the in vivo electrical properties of a guinea pig cochlea implanted with a multielectrode stimulating array. A basic model of the low-frequency electroanatomy in a normally functioning guinea pig cochlea is developed by adding critical membrane capacitances to Strelioff's resistive network model [1]. The basic model of normal cochlear tissues is modified to account for anatomical and physiological differences between a normal and implanted cochlea, which results in an impedance model of an implanted cochlea. Simulating the results of in vivo cochlear stimulation verifies the accuracy with which the modified cochlear model represents electrical properties within an electrically stimulated cochlea. Generalized simulations using this model suggest a straightforward phasing scheme capable of achieving sharply focused, channel-independent multielectrode cochlear stimulation.     

Treatment of intractable Menière's disease with intratympanic gentamicin: review of the University of Ottawa experience

OBJECTIVE: Intractable Meniere's disease has traditionally been treated surgically, with either labyrinthectomy, vestibular nerve section, or endolymphatic sac procedures. Another option is the use of intratympanic gentamicin to effect a 'gentamicin labyrinthectomy.' Nedzelski and coworkers have previously reported an 83% complete elimination and 17% substantial reduction in vertigo using this method. METHOD: We retrospectively reviewed 21 patients treated at our centre with intratympanic gentamicin between 1991 and 1995, all of whom fulfilled the criteria for reporting results in Meniere's therapy described in the American Association of Otolaryngology Committee on Hearing and Equilibrium 1995 guidelines. Our patients are presented using these guidelines, specifically examining four criteria: frequency of vertigo, word recognition, functional level, and hearing threshold. RESULTS: At 2-year follow-up, 17 of 21 patients (80.9%) had complete elimination of vertigo, with 3 of 21 (14.3%) reporting a 60 to 99% reduction in frequency. Nineteen of 21 patients (90.5%) described themselves as having no impairment secondary to dizziness. Average hearing thresholds and word-recognition scores appear to have both worsened after gentamicin therapy. CONCLUSION: Intratympanic gentamicin therapy for vertigo in Meniere's disease was shown to be an effective treatment choice, as shown by our results. However, with the reduction of average hearing thresholds and word-recognition scores, patients should be advised of these possible complications as part of informed consent.     

Alterations in the distributions of the basement membrane components after secondary inner ear immune reaction in guinea pigs

Alterations in the distributions of type IV collagen (C-IV), laminin (La), and fibronectin (Fib), which are important components of the basement membrane, in the inner ear following secondary endolymphatic sac immune response were studied immunohistologically using control animals for comparison. Endolymphatic hydrops developed following direct secondary keyhole limpet hemocyanin (KLH) challenge to the endolymphatic sac in systematically pre-sensitized animals. In the endolymphatic sacs of control animals, C-IV and La were localized continuously just under epithelial cells whereas Fib was present intermittently in subepithelial connective tissue. In the endolymphatic sac, following secondary KLH challenge, linear subepithelial localizations of C-IV and La were interrupted, thinner and more loosely aggregated with numerous inflammatory cellular infiltrates on days 2-4. Following these changes, endolymphatic hydrops in the cochlea developed and peaked on days 4-7. On days 1-7, Fib was strongly but sporadically localized in subepithelial cells. These results suggest that C-IV and La may play important roles in the regulation of endolymph whereas Fib may be related to the restoration of injured endolymphatic sac tissue in animals exposed to a secondary challenge.     

The role of allergy in Meniere's disease

There is considerable clinical and immunologic evidence for a probable role of allergy in the production of the symptoms of Meniere's disease. The endolymphatic sac is the seat of immune reactivity in the inner ear. Inhalant and food allergies have been linked with symptoms of Meniere's disease, and many of the clinical characteristics of Meniere's disease suggest an underlying autoimmune etiology. A significant percentage of patients with Meniere's disease and allergy show improvement in their symptoms of tinnitus and vertigo when receiving specific allergy therapy.     

Betahistine hydrochloride in Méniére's disease

A double-blind, placebo-controlled, cross-over clinical trial was performed to assess the effect of betahistine hydrochloride (Serc) in Ménière's disease. The diagnosis was based on paroxysmal attacks of rotational vertigo, with tinnitus, and a fluctuating sensori-neural deafness, together with the results of auditory and vestigular tests. Twenty-eight patients were admitted to the trial over 3 years. Twenty-two patients completed the trial. In total, they received betahistine 32 mg daily, for a period of 16 weeks, and placebo also for the same length of time, preceded in every case by a 4-week pre-treatment period. Daily symptom score cards were kept. There was a statistically significant improvement in favour of the drug with regard to vertigo, tinnitus and deafness. Vertigo was the most responsive symptom. No adverse reactions were observed.     

Playground safety

A female patient is described who had a four year long period of unilateral chronic paroxysmal hemicrania (CPH) which then became bilateral. For some years before the CPH started she suffered from periods of about one month with chronic hemicrania without nerve involvement. She also suffered from chronic fatigue, back pain, arthralgia, vertigo, chronic constipation and spontaneous ecchymoses. Blood tests showed chronic leukocytosis, low serum iron, and signs of inflammation in serum electrophoresis during the five years she was studied. CPH attacks could be provoked by breathing 6% carbon dioxide in air. Lumbar cerebrospinal fluid pressure was pathologically increased (30 cm water). The attacks decreased during indomethacin treatment but 275 mg was needed for satisfactory control of the attacks, i.e., more than the 150 mg which, according to the criteria for CPH, should be absolutely effective. Sumatriptan was found to suppress the CPH attacks as well as indomethacin. Due to these findings CPH is considered to be another manifestation of venous vasculitis. The beneficiary mechanism of indomethacin in CPH is considered to be due partly to its anti-inflammatory effects and partly to its reduction of the intracranial blood flow.     

The natural course of Meniere's disease

The case history and disability of 111 patients suffering from Meniere's disease are reported. Observed for more than 5 years, the patients have had no, or only medical treatment, in most cases of short duration. The number of patients disabled and their degree of disability seems to justifiy surgical treatment in patients with frequent and incapacitating attacks of vertigo.