Motion Sickness: Causes, Symptoms, and Solutions - Otolaryngology

Dr. Ye Dawei reply Otolaryngology

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A Discussion on Dizziness: A Voice from a Dizziness Specialist
I often treat patients with dizziness in my clinic.
From my initial fear of the dizziness specialty clinic around 1982 to now being able to listen to their pain, the journey of practicing medicine has been quite enlightening.
Dr.
Yang Yi-hsiang has a chapter in his book "Dizziness Reception" that describes these amusing yet frustrating patients.
One of the biggest nightmares for any ENT resident is receiving a new patient whose chief complaint is dizziness, and I was no exception.
I remember when Director Fan assigned me to the dizziness specialty clinic, the usually gentle me surprisingly raised my voice to refuse on the spot (I respect the director, but I fear dizziness even more :-)).
Those who have followed the dizziness clinic must have a deep impression of how these patients often provide irrelevant answers.
When asked how they feel dizzy, they might respond with complaints about their ungrateful daughter-in-law or their harsh mother-in-law.
Thus, every Tuesday afternoon's dizziness specialty clinic became a headache for me.
Once, in the clinic, an elderly woman complained about her dizziness and how one side of her head felt like it was splitting, then suddenly shifted to discussing how she was mistreated by her mother-in-law in her youth and how fortunate her daughter-in-law is now.
I always took these opportunities to practice translating their complaints in my head, either from Chinese to Japanese or Chinese to English; otherwise, I wouldn't know how to get through those long afternoons.
I've forgotten the face of that elderly woman (they all look alike, even their walking and speaking styles), but I remember that she shed tears in front of me while saying, "I was so beautiful before I married into my husband’s family.
When I was a conductor, many young men would deliberately take my bus, but they tortured me, causing me migraines and 'dark dizziness'..." After her tears, I had to stop my mental gymnastics but didn't know how to comfort her.
However, after that experience, the time I spent on mental gymnastics in the clinic gradually decreased, and my sincere listening to their complaints unknowingly increased.
Behind every patient lies a significant history.
What I once least wanted to hear—these non-academic complaints—seemed to transform into the most pleasant melodies, and the domestic grievances of these dizziness patients became our most intimate secrets.
Even after starting my practice, some dizziness patients still come to see me, needing long-term medication, so I often refer them to provincial hospitals.
Once, a woman recounted her struggles to take her dizzy mother to a metropolitan medical center for registration, detailing how she faced difficulties getting leave from school.
After overcoming obstacles to find time to visit the medical center, she ended up having to reschedule for the next appointment (hearing tests, eye movement tests, or CT scans) but canceled due to the exhausting journey.
Without listening further to her complaints about unreasonable treatment at the hospital, I looked at the elderly woman sitting in front of me, unable to maintain an upright posture due to dizziness, and felt an indescribable emotional tug—was it excitement, compassion, or sympathy?
Treating dizziness, no matter how advanced the technology, cannot compare to detailed history-taking, thorough physical examinations, and a compassionate attitude.
In general outpatient consultations, asking questions can easily disrupt the flow of the consultation, so I decided to allocate the first 20 minutes of each clinic session to schedule dizziness patients.
Although this meant adding nearly an hour to my daily clinic time, I initially found it physically taxing (the comprehensive history-taking, local ENT examinations, eye movement tests, head position eye movement tests, head position change eye movement tests, head shaking eye movement tests, posture reflex tests, and stepping tests are quite exhausting), it became a sweet burden.
If possible, and if there are enough patients, I hope to maintain this practice.
For colleagues who have referred dizziness patients to me, I always strive to treat them with respect.
Although I lack eye movement charts, EEGs, CT scans, and MRIs, I hope to provide dizziness patients with better care than they would receive at a medical center.
Physiology and Pathology of the Human Balance System
The human balance system relies on visual, proprioceptive, and vestibular functions to maintain equilibrium, with the inner ear referred to as the "labyrinth." Renowned writer Yu Qiuyu mentioned in the November 5th edition of the United Daily News Supplement, in his piece "Millennium Pilgrimage," the dizzying Palace of Knossos, writing: "The story goes that a half-man, half-bull monster was locked in this Minoan palace, and every year, Athens had to send seven pairs of young men and women as sacrifices.
A young man named Theseus resolved to abolish this evil practice and conspired with his father to mingle among the youths and venture to Crete to find an opportunity to subdue the monster.
This endeavor was fraught with danger; his father promised to watch from a cliff, and if a ship with a white sail appeared on the sea, it would signify success; if a ship with a black sail arrived, it would mean his son had died.
Theseus subdued the monster in the Minoan palace but could not find his way out of the labyrinth.
The daughter of King Minos fell in love with him and helped him escape.
However, while drifting at sea, the princess suddenly died, and in his grief, Theseus forgot to change the ship's black sail to white.
His father, anxiously watching from the cliff, saw the black sail and, fearing the worst, jumped into the sea, and his name was Aegeus..."
The labyrinth in this tragic story has a characteristic: once entered, one will proceed along its spiral paths and never find the exit, which is why "labyrinth" in Latin means "pathway." Physicians studying the labyrinth (inner ear) often find its complex functions difficult to comprehend, much like the young man Theseus lost in the maze.

On the same day, another article titled "Understanding Vincent's Voice" discussed the story of the Impressionist painter Vincent Van Gogh.
Modern medical research suggests that Van Gogh suffered from Meniere's disease, as his letters reveal he frequently struggled with tinnitus and dizziness in daily life.
The famous painting "Starry Night" has even been interpreted by ENT specialists as depicting the counter-clockwise rotation caused by left ear pathology during a Meniere's attack, as seen in the swirling waves in the painting.
His struggles with tinnitus, a sensation of ear fullness, and auditory hypersensitivity led him to cut off his left ear and frequently argue with fellow painter Gauguin, further triggering his dizziness episodes.

In the first year of college, while listening to Don McLean's song "Vincent," I found the melody beautiful but was unaware of the tragic life of the song's protagonist.
The vestibular receptors in the inner ear consist of two types of five structures, including three ampullae (crista ampullaris) from each of the three semicircular canals and the maculae (saccule and utricle) of the otolith organs.
The semicircular canals are responsible for detecting angular acceleration and deceleration, such as rotation, pitch, and roll, which are non-linear movements; the saccule detects vertical linear acceleration, while the utricle detects horizontal linear acceleration or deceleration.
Constant velocity does not stimulate the vestibular system.
The vestibular system transmits gravitational and acceleration stimuli to the central nervous system, first reaching the vestibular nuclei in the brainstem, which then integrates information from the eyes and proprioceptors and sends it to five areas: 1.
The cerebral cortex, which interprets head position and spatial orientation.
2.
The cerebellum, responsible for muscle coordination to maintain balance.
3.
The eye muscles, to maintain visual fields.
4.
The spinal cord, to maintain muscle tone for posture.
5.
The vagus nerve nucleus, to maintain normal gastrointestinal motility.
If there is a pathological change affecting the normal balance system, the vestibular nuclei will receive unbalanced signals, leading to the following conditions: 1.
The cerebral cortex interprets this as dizziness or vertigo.
2.
The cerebellum may cause ataxia.
3.
Excitation of the ocular motor nuclei leads to nystagmus.
4.
Excitation of the spinal cord causes righting reflexes.
5.
Excitation of the vagus nerve nucleus leads to retroperistalsis, causing nausea and vomiting.
Additionally, the cerebellum will send signals to suppress the function of the normal side's vestibular system, reducing imbalance and promoting central nervous system compensation.
Dizziness Disorders Overview
Clinically, we often simply categorize dizziness into peripheral dizziness, which refers to pathology limited to the inner ear, and central dizziness, which indicates pathology in the brain, along with motion sickness.
The central nervous system can compensate for inner ear imbalances, which can occur within one or two days, and at most, complete compensation occurs within three weeks.
Therefore, symptoms of peripheral vestibular disorders should not persist for four weeks.
Peripheral vestibular imbalance is always accompanied by nystagmus and dizziness; nystagmus, derived from the Greek word meaning "to doze," occurs because when dozing off, the head slowly tilts downward and, at a certain angle, suddenly corrects itself reflexively, resembling the nystagmus seen in dizziness patients.
Nystagmus consists of a slow phase followed by a rapid phase; the slow phase is controlled by the inner ear, while the rapid phase is a reflex controlled by the brainstem.
The so-called visual fixation suppression means that keeping the eyes open can make nystagmus disappear or weaken; if this ability is lost, it indicates central nervous system pathology.
The following are common dizziness disorders:
1.
Meniere's Disease: When the general public thinks of dizziness, they often think of "Meniere's," and even general practitioners frequently diagnose it as such.
However, there are not as many cases of Meniere's disease as one might think; many patients complain of dizziness and are overdiagnosed by physicians.
If the number of Meniere's cases is disproportionately high in a neurotology clinic, the physician's competence may be questioned.
In simple terms, if a patient presents with dizziness, tinnitus, and hearing loss, the physician will consider this disease.
The famous Japanese physician Ichiro Chikubai described it as "7 points disease" due to the following characteristics: 1) Severe dizziness: it feels as if the world is spinning and can last for several hours, with the first episode being the most intense.
2) Spontaneous dizziness: it occurs without any triggers and can strike suddenly.
3) Recurrent dizziness: patients with Meniere's disease often experience repeated episodes, rarely just one occurrence.
4) Reversible dizziness: there are periods of complete normalcy between episodes, and dizziness does not persist for days.
5) Dizziness accompanied by cochlear nerve symptoms: patients often experience fluctuating hearing loss, with severe tinnitus during acute episodes, and sometimes perceive sounds of different frequencies.
6) Hearing loss is often more pronounced at low frequencies.
7) Patients may experience a "reverberation phenomenon," often complaining of discomfort in noisy environments, such as markets or train stations.
To date, no laboratory tests can definitively diagnose Meniere's disease, making detailed medical history and basic physical examination crucial.
Patients often experience unforgettable episodes of severe dizziness accompanied by tinnitus, a sensation of ear fullness, and hearing loss.
Unlike "benign paroxysmal positional vertigo" (BPPV), which lasts only a few seconds, or "vestibular neuritis," which can last for several days, most patients experience dizziness for about 3 to 4 hours before gradually alleviating, only to have it recur weeks later.
Many elderly patients report having recurrent dizziness since their youth, with gradually worsening hearing and persistent tinnitus.
This disease commonly occurs between the ages of 20 and 40 and has a maternal inheritance pattern.
The cause is believed to be endolymphatic hydrops in the inner ear, leading to a sensation of ear fullness.
Treatment primarily involves medical management, including neurotropic agents, vasodilators, and mild sedatives.
If episodes occur monthly, treatment should last at least four months; if they occur every two months, treatment should last at least five months, which is the interval between symptom occurrences plus three months.
If medical treatment is ineffective or the patient cannot tolerate long-term medication, endolymphatic decompression surgery may be considered.
2.
Vestibular Neuritis: The eighth cranial nerve, which innervates the inner ear, consists of the cochlear nerve responsible for hearing and the vestibular nerve responsible for balance.
The vestibular nerve is more susceptible to viral infections, which can lead to severe dizziness.
Its characteristics include: 1) Severe dizziness, often so intense that the patient cannot get out of bed, but without symptoms of auditory nerve involvement, such as tinnitus or hearing loss.
2) Occurs primarily in individuals aged 20 to 50.
3) Dizziness often occurs only once but can last for several days, while the sensation of imbalance may persist for weeks or even months.
4) The affected ear may show a reduced response to water irrigation, without dizziness or central nervous system symptoms.
5) Patients typically recover within six months.
6) A recent history of upper respiratory infections within the last 1 to 3 weeks.
3.
Benign Paroxysmal Positional Vertigo (BPPV): As the name suggests, this is a benign, sudden-onset condition related to changes in head position.
Its characteristics include: 1) Dizziness occurs when the head is turned to a certain angle but disappears with a change in position.
For example, lying on one side may trigger dizziness, indicating that side is affected.
2) Dizziness typically lasts seconds and does not exceed 30 seconds.
3) There is usually a latency period of about 5 to 10 seconds before dizziness and nystagmus occur after turning the head to a certain angle, and if the position is maintained for about 5 to 45 seconds, the symptoms gradually diminish.
Repeated head movements can lead to desensitization and cessation of dizziness.
4) During dizziness episodes, patients often experience autonomic symptoms such as nausea, vomiting, and cold sweats, but there are no auditory nerve symptoms like tinnitus or hearing loss.
5) When the patient is in a head-hanging position, clockwise nystagmus occurs, while rapidly sitting up results in counter-clockwise nystagmus, a unique counter-rolling phenomenon of BPPV.
Regarding the pathophysiology of BPPV, Dix and Hallpike noted in 1952 that the pathology is not in the brain but in the utricle of the inner ear; Harvard's Schuknecht further theorized that the condition arises from dislodged otoliths floating into the endolymph of the semicircular canals, stimulating the canal's sensory receptors and inducing dizziness.
What causes otoliths to dislodge? 1) Head trauma is the most common cause.
2) Noise exposure, such as shooting.
3) Drug toxicity, such as with streptomycin or kanamycin.
4) Chronic otitis media affecting the otolith organs.
5) Surgical damage to the utricle.
6) Obstruction of the vestibular artery supplying the utricle.
7) Aging.
The utricle and saccule are both otolith organs in the inner ear, with the semicircular canals responsible for rotational sensations, while the otolith organs manage linear motion sensations.
The saccule detects vertical movements, while the utricle detects horizontal movements.
Even without treatment, the otoliths floating in the endolymph will dissolve on their own, leading to spontaneous recovery within 3 to 6 months.
Medications can alleviate symptoms, and patients are encouraged to slowly turn their heads toward the affected side to reduce dizziness.
4.
Sudden Hearing Loss: "Sudden" means that patients can clearly indicate a specific day or even moment when they suddenly lost hearing or experienced severe tinnitus.
This is an ENT emergency, and patients are generally advised to seek immediate hospitalization.
Some patients may also experience dizziness and vomiting, necessitating differentiation from Meniere's disease.
Typically, dizziness occurs only once, lasting a day or several days before resolving, but hearing loss and tinnitus persist.
Meniere's disease, on the other hand, often involves recurrent dizziness, but hearing usually recovers more quickly after episodes.
Some cases of acoustic neuroma may also present with sudden hearing loss, requiring CT scans for differential diagnosis.
The causes are widely accepted to include inner ear circulatory disturbances, viral infections, and autoimmune diseases.
Current treatment approaches have moved away from a "shotgun" approach, focusing instead on treating the specific underlying cause.
1) Inner ear circulatory disturbances: Blockage or spasms of the blood vessels supplying the inner ear can lead to hypoxia and hearing loss.
This is more common in patients with systemic vascular diseases such as diabetes, hypertension, or hyperlipidemia.
Therefore, treatment primarily involves plasma expanders (e.g., Dextran) to improve blood flow by reducing blood viscosity and preventing thrombosis.
2) Viral infections: Many viruses can infect the inner ear, such as the rubella virus and cytomegalovirus, which can cause congenital deafness; mumps virus, measles virus, herpes zoster virus, and the currently prevalent influenza virus can lead to acquired deafness.
Treatment typically involves corticosteroids, starting with a dose of 60 mg per day for six days, then tapering over two weeks.
3) Autoimmune diseases: Patients often have systemic autoimmune diseases, such as lupus or rheumatoid arthritis, and may experience bilateral hearing loss.
Before treatment, history, physical examination, and electronystagmography (ENG) can help preliminarily determine whether the cause is central or peripheral.
Patients are generally advised to be hospitalized for at least a week; if hearing does not improve, they may be discharged, but if there is improvement, they may stay for another week.
During hospitalization, daily hearing tests and monitoring of eye movement changes are conducted, with follow-up every two weeks after discharge for three months.
Several indicators influence prognosis: 1) The earlier treatment begins, the better the prognosis; 2) Patients with high-frequency hearing loss tend to have a poorer prognosis; 3) Those with dizziness have a worse prognosis, while those with tinnitus still have cochlear nerve function, indicating a better prognosis; 4) Older patients tend to have a poorer prognosis.
5.
Cervical Dizziness: Each side of the neck has a vertebral artery connected to the basilar artery of the brainstem.
If cervical spine deformities, bone spurs, or foraminal stenosis compress the vertebral artery, it can lead to poor blood flow to the inner ear, resulting in dizziness.
This condition must be differentiated from BPPV; generally, cervical dizziness is shorter in duration, milder in symptoms, occurs at an older age, and lacks the counter-rolling nystagmus characteristic of BPPV, often accompanied by neck or shoulder stiffness and pain.
6.
Tumarkin's Catastrophe: Patients may suddenly collapse without warning, remaining fully conscious throughout the episode, which can occur several times a day.
The cause remains unclear but may involve sudden loss of muscle tone in the affected side due to dysfunction of the otolith organs.
7.
Acoustic Neuroma: The acoustic nerve runs from the inner ear to the brainstem, with tumors most commonly appearing at the opening of the internal auditory canal, known as the cerebellopontine angle (CPA).
Initially, patients may only experience gradual unilateral hearing loss or tinnitus.
This tumor grows very slowly, so although it compresses the vestibular nerve, central compensation usually prevents dizziness.
As the tumor enlarges and compresses blood vessels, it can lead to sudden hearing loss or dizziness, with symptoms becoming increasingly diverse as the disease progresses.
If the tumor is confined to the internal auditory canal and is less than 1 cm, it may be difficult to detect on CT scans.
Some have proposed performing a lumbar puncture to introduce air into the brain's ventricles, allowing the patient to lie on their side so that air enters the internal auditory canal.
If an acoustic neuroma is present, the air will not fill the internal auditory canal, known as "air CT." However, this method can cause headaches for about a week due to the air in the skull.
With the advent of MRI, tumors smaller than 1 cm can now be easily diagnosed.
If the tumor grows larger and extends toward the cerebellum or brainstem, it can become life-threatening.
Clinically, patients may present with normal hearing but no response in auditory brainstem responses, necessitating consideration of this condition.
8.
Labyrinthine Dysfunction: I frequently use this diagnosis in my clinic because many patients do not fully meet the definitions of the individual diseases mentioned above, and the clinic lacks specialized instruments for differential diagnosis.
However, it can still be confirmed that the pathology is limited to the inner ear and does not involve the central nervous system, providing reassurance to patients and their families.
Although this condition can resolve spontaneously (remember that the central nervous system can compensate), medication can shorten the duration of the illness and alleviate suffering.
Central Dizziness: As the name suggests, central dizziness is caused by brain diseases, with the most common being "vertebrobasilar insufficiency." This artery begins with the two vertebral arteries in the neck, merging into the basilar artery at the cerebellum and brainstem, which then branches into the posterior inferior cerebellar artery, anterior inferior cerebellar artery, and superior cerebellar artery; among these, the anterior inferior cerebellar artery further branches into the internal ear artery supplying the inner ear, making it sometimes difficult to distinguish from peripheral lesions.
Clinically, peripheral lesions typically present as sudden and intermittent episodes lasting seconds, minutes, hours, or at most several days, with dizziness characterized by intense spinning sensations, exacerbated by changes in head position, and less dizziness when the affected ear is facing up.
In contrast, central lesions are usually gradual and persistent, with episodes lasting months, less intense spinning sensations, and changes in head position not worsening dizziness, with less dizziness when the affected ear is facing down.
These are basic principles, and further history, physical examination, blood tests, and instrumental examinations are necessary for accurate diagnosis.
1.
Vertebrobasilar Insufficiency: This condition often presents early with dizziness, sometimes accompanied by nausea, vomiting, or bilateral tinnitus.
Another characteristic is the appearance of symptoms specific to brain lesions, such as dysarthria, difficulty speaking, swallowing difficulties, diplopia, sensory disturbances, and limb weakness or numbness.
Elderly patients with hypertension, diabetes, hyperlipidemia, or cervical spondylosis are more likely to develop this condition; if younger individuals are affected, it is often related to family history and genetics.
2.
Basilar Artery Migraine: This is a type of migraine where dilation of the artery causes headaches, while constriction leads to dizziness.
It primarily affects young women and is often related to menstruation, with a maternal family history.
Symptoms include dizziness, tinnitus, blurred vision, unsteady gait, occipital pain, and even loss of consciousness.
Careful inquiry into dietary habits often reveals a preference for cheese, chocolate, tomatoes, and orange juice, as these foods contain amino acids that can cause abnormal vascular constriction.
Patients are typically prescribed calcium channel blockers for three months and advised to avoid these foods.
3.
Benign Recurrent Vertigo (BRV): This condition affects children, who experience unexplained recurrent episodes of dizziness lasting about 20 minutes, occurring several times a month.
Symptoms often arise in the morning due to changes in posture, such as nausea, vomiting, pallor, or cold sweats, sometimes accompanied by headaches but without tinnitus.
Because these symptoms can occur suddenly and intensely, they often cause significant concern for parents.
It is now believed to be caused by spasms of the basilar artery, leading to insufficient blood supply to the inner ear, and family histories of migraines or dizziness are often revealed during consultations.
Treatment primarily involves calcium channel blockers, which have shown excellent results, with over 90% of children improving within two weeks of treatment, although they should continue for three months.
If children do not continue treatment for three months, they are more likely to develop basilar artery migraines in adulthood.
4.
Orthostatic Dysregulation (OD): This is a common dizziness condition in children caused by autonomic nervous system dysregulation, leading to dizziness, pallor, cold sweats, or even inability to stand when suddenly standing up.
Many schoolchildren complain of discomfort upon waking in the morning, which gradually improves by the afternoon.
Patients experience a drop in blood pressure and an increase in heart rate when standing, and the opposite occurs when lying down.
5.
Cerebellar Hemorrhage or Infarction: Early cerebellar lesions are very difficult to diagnose, often presenting solely with dizziness.
In addition to detailed history-taking and physical examination, electronystagmography can reveal characteristic abnormal eye movements in the early stages.
The cerebellum can be anatomically divided into three parts: the "primitive cerebellum," referring to the lower vermis and nodulus, primarily responsible for maintaining posture, also known as the vestibular cerebellum; the "old cerebellum," including the anterior and posterior vermis, which connects to the spinal cord and is responsible for higher-level continuous movements; and the "new cerebellum," which comprises the two cerebellar hemispheres, responsible for coordinating movements of the body's trunk muscles.
If there are lesions in the cerebellum or its incoming or outgoing nerve fibers, symptoms of motor system disorders may arise, such as unsteady gait, headaches, dizziness, and vomiting.
6.
Cerebellar Tumors: Commonly seen are "cerebellar meningiomas," which predominantly occur in women aged 40 to 50 during menopause.
Initially, there are no specific symptoms, and at this age, patients often have vague complaints such as headaches, depression, or anxiety, which Japanese doctors refer to as "indeterminate complaints." If middle-aged women present with such vague complaints, clinicians must rule out the possibility of cerebellar meningiomas.
7.
Cerebellar or Brainstem Infarction or Hemorrhage: The greatest fear in the dizziness clinic is misdiagnosing this condition as a common peripheral disorder and delaying treatment, which could be fatal.
Its characteristics include persistent and severe dizziness, intense headaches, altered consciousness, and specific changes in eye movements.
If this condition is suspected clinically, CT or MRI scans should be performed.
Motion Sickness: Dizziness arises from an imbalance in the balance system, while motion sickness is distinct from peripheral and central disorders.
It can be described as a reflexive dizziness caused by the motion of various transportation modes (land, sea, air), leading to abnormal impulses from the semicircular canals and otolith organs, resulting in dizziness and nausea.
The causes are numerous and can be divided into internal factors (such as fatigue, colds, alcohol consumption, lack of sleep, or gastrointestinal discomfort) and external factors (excessive motion of transportation, visual stimuli causing "perceptual conflict," such as looking at the wavy sea while on a boat, or sensory stimuli like smelling oil, seeing someone vomit, or hearing engine noise).
These factors collectively create a preparatory state for motion sickness, triggering autonomic nervous system dysregulation, leading to symptoms such as nausea, vomiting, gastrointestinal discomfort, cold sweats, unsteady gait, increased heart rate, elevated blood pressure, and headaches.
To prevent motion sickness, it is essential to avoid the aforementioned internal and external factors.
If necessary, Bonamine can be taken 30 minutes before travel; taking it after symptoms have started is ineffective.
If nausea persists during travel, focusing on an object one meter ahead can help suppress symptoms through central visual fixation suppression.
Common medications include antihistamines and anticholinergics to calm the autonomic nervous system, with each treatment course lasting three months.
Motion sickness can improve through training, as fishermen, astronauts, and pilots have adapted well to it.
What Dizziness Doctors Want to Know
As mentioned earlier, dizziness patients often provide irrelevant answers during consultations, making it particularly important for physicians to guide the questioning.
I often use a "Dizziness, Tinnitus, and Headache Specialty Clinic Questionnaire" to ensure I do not miss important information.
- What is your occupation? Is there potential exposure to chemical pollutants? Is your work environment noisy? Painters, gas station attendants, drivers, or aircraft engine technicians may be exposed to organic solvents like toluene or styrene, causing dizziness; noise exposure or acoustic trauma can lead to tinnitus and dizziness.
- Is there a family history? Some diseases, such as Meniere's disease and basilar artery migraines, tend to have maternal inheritance patterns.
- Are you taking any long-term medications? Many medications can cause dizziness, including contraceptives, antihypertensives, and antiepileptics.
In the past, children often received streptomycin injections, or tuberculosis patients received injections of kanamycin, which could also cause dizziness and tinnitus.
- Have you had a cold recently? Have you gone hiking or diving? Have you flown recently? A recent cold may lead to "vestibular neuritis," while hiking or diving can cause sudden pressure changes, potentially leading to serous otitis media or inner ear window rupture, resulting in dizziness.
- What is the nature of your dizziness? Is it spinning, floating, rolling, or swaying? If the dizziness is "clockwise or counter-clockwise," it is often due to inner ear pathology, but cerebellar or brainstem hemorrhage or infarction should also be considered; "back-and-forth" dizziness may indicate central lesions in the cerebellum or brainstem; "floating" dizziness, where walking feels heavy-headed, suggests vascular issues in the cerebellum; "swaying" dizziness, reminiscent of an earthquake, may indicate tumors in the cerebellum, brainstem, or cerebellar vermis.
- Do you lean while walking? Which side do you lean toward? Have you ever collapsed suddenly? Generally, leaning forward or backward suggests central lesions, particularly cerebellar issues; leaning to the left or right may indicate peripheral lesions, such as inner ear disorders, which typically lean toward the affected side.
"Tumarkin's catastrophe" may cause sudden collapse while remaining conscious.
- How long do your dizziness episodes last? How often do they occur? During the day or at night? Dizziness from "benign paroxysmal positional vertigo" lasts only a few seconds, while "Meniere's disease" often lasts several hours, and "vestibular neuritis" can last several days.
Central lesions may last from seconds to minutes, so other symptoms must be considered for differential diagnosis.
"Meniere's disease" often occurs in the morning upon waking, while "vertebrobasilar insufficiency" may occur at night, especially when getting up to use the restroom.
- Is your dizziness related to a specific posture? Does a certain posture worsen or alleviate your dizziness? Patients with Meniere's disease often prefer to lie with the affected ear facing up, while those with cerebellar hemorrhage may prefer the affected ear facing down to relieve pressure on brain tissue.
Patients with BPPV experience dizziness when turning their heads to a specific angle, but repeated movements can desensitize them, while those with malignant BPPV can hardly move their heads at all.
- Are there any accompanying symptoms such as nausea, vomiting, cold sweats, pallor or flushing, shoulder pain, neck stiffness, headaches, heaviness in the head, or occipital pain? Since the vestibular nuclei in the brainstem are connected to the vagus nerve nuclei, dizziness patients may experience these autonomic symptoms.
"Headaches or heaviness" must rule out central tumors, while "occipital pain or heaviness" may suggest toluene poisoning or inhalation of strong adhesives; "neck stiffness, shoulder pain, or head pain" may indicate vertebrobasilar insufficiency.
- Are there any hearing impairments, tinnitus, a sensation of ear fullness, sensitivity to loud sounds, ear pain, or ear discharge? "Benign paroxysmal positional vertigo" and "vestibular neuritis" do not typically present with tinnitus, while "Meniere's disease" involves a sensation of ear fullness and sound sensitivity.
- Are there any numbness in the limbs or around the mouth? Blurred vision or temporary blindness? Difficulty speaking or swallowing? "Numbness in the limbs" may indicate vertebrobasilar insufficiency or a stroke warning; "blurred vision or blindness" may suggest central vascular disease; "difficulty speaking or swallowing" may indicate blockage of the posterior inferior cerebellar artery.
Dizziness Examinations
The advancements in modern medicine are remarkable, with cutting-edge instruments evolving rapidly.
However, when it comes to diagnosing and treating dizziness, one must not overlook the importance of medical history and basic physical examinations.
I personally believe that these are far more important than advanced technologies like electronystagmography, CT scans, or MRIs, as often, instrumental examinations merely confirm whether our hypotheses are correct.
What examinations should we conduct for dizziness?
1.
Detailed Medical History: Many clues can be found in the questionnaire; experienced physicians can often preliminarily distinguish between central and peripheral lesions based solely on the questionnaire and assess any immediate life-threatening risks.
2.
Local ENT Examination: This can rule out certain ENT diseases and conditions such as earwax, otitis media, cholesteatoma, sinusitis, or nasopharyngeal cancer.
3.
Gaze-Evoked Nystagmus Test: Position yourself about 50 cm from the patient, asking them to focus on your fingertip while moving it up, down, left, and right by 30 degrees to observe for nystagmus.
A special concave lens (Frenzel goggles) can magnify eye movements and eliminate external stimuli, making it easier to observe changes in nystagmus.
4.
Head-Shaking Nystagmus Test: This method has the highest induction rate, and any resulting nystagmus is clinically significant, making it a common screening test for follow-up patients.
5.
Head Position Nystagmus Test: Have the patient lie flat and turn their head left and right to observe for nystagmus; patients with BPPV can often be induced to show nystagmus during this test.
6.
Head Position Change Nystagmus Test: Observe for nystagmus when the patient quickly moves from a sitting position to a head-hanging position; patients with central lesions like vertebrobasilar insufficiency often show downward nystagmus.
7.
Stepping Test: Normal individuals can maintain balance with their eyes closed, with a deviation angle not exceeding 30 degrees and a distance of no more than 1 meter.
Those with poor inner ear function will lean toward the affected side, while cerebellar patients may struggle to maintain balance even with their eyes open.
8.
Postural Reflex Test: This includes the Romberg test, which assesses the patient's ability to maintain an upright position, and tandem walking, where the patient walks in a straight line with their heel touching their toe.
Cerebellar patients often cannot perform this test.
9.
Vertical Writing Test: Have the patient write a line of text with their elbow hanging vertically, comparing the slant of the writing with eyes open and closed.
Patients with inner ear disorders will show a tendency to slant toward the affected side when their eyes are closed, while cerebellar patients may struggle to recognize their writing.
10.
Eustachian Tube Test: Using a Politzer balloon, apply it to the external auditory canal while having the patient tilt their head back 60 degrees and alternately squeeze and release the balloon.
If there is a dysfunction (e.g., inner ear syphilis, cholesteatoma, or rupture of the inner ear window), dizziness and nystagmus will occur.
11.
Temperature Response Test: Have the patient lie flat and flex their head forward 30 degrees, then irrigate with water at 30°C and 44°C.
Normal patients will show nystagmus within about 15 seconds, lasting 2 to 3 minutes; less than 1 minute indicates dysfunction of the inner ear, typically peripheral lesions, while more than 3 minutes suggests loss of cerebellar control over the inner ear, indicating central lesions.
12.
X-ray Examination: X-rays of the middle ear, mastoid, inner ear canal, and cervical spine can reveal conditions such as otitis media, tumors invading the inner ear canal, or bony spurs or deformities in the neck.
13.
Blood Tests: Complete blood counts, blood glucose, cholesterol, triglycerides, syphilis serology, and thyroid function tests are important, as related systemic diseases can also cause dizziness.
14.
Hearing Tests:
- Pure Tone Audiometry (PTA) can screen for conductive or sensorineural hearing loss.
- Tympanometry can check for middle ear effusion, Eustachian tube obstruction, and stapes reflex.
- Auditory Brainstem Responses (ABR) assess the auditory nerve pathway from the inner ear to the brainstem, with five waves; if there is a lesion, the wave may be absent or delayed.
If PTA is normal but ABR is abnormal, acoustic neuroma must be considered.
- Otoacoustic Emissions (OAE) can detect whether cochlear cells can emit sound, commonly used for newborn hearing screening.
15.
Electronystagmography (ENG): This can reveal characteristic abnormal eye movements in the early stages of cerebellar lesions, using electrodes placed on either side of the eyes to record the potential difference between the retina and cornea.
Observing changes in eye movements can lead to early diagnosis of many neurotological diseases before physical symptoms appear.
16.
Postural Stability Testing: ENG assesses the vestibulo-ocular reflex, while postural stability tests quantitatively evaluate the vestibulo-spinal reflex.
Common Medications for Treating Dizziness
Medications commonly used by physicians to treat dizziness can be categorized as follows:
1.
Vasodilators: Many dizziness patients experience symptoms due to poor vascular circulation, so vasodilators are often used.
Since microvessels have a diameter of about 3 micrometers and red blood cells about 7 micrometers, merely dilating blood vessels is insufficient; ideal medications should also enhance red blood cell deformability and reduce blood viscosity.
Common vasodilators include:
- Tebonin: Commonly known as ginkgo biloba, it promotes cerebral circulation, has antiplatelet effects, and clears free radicals.
- Euclidan: A well-established peripheral dizziness vasodilator.
- Cephadol: An antihistamine and anticholinergic medication for dizziness.
- Sibelium: A calcium channel blocker that prevents calcium ions from entering vascular smooth muscle, inhibiting vasoconstriction and promoting vasodilation.
2.
Neurotropic Agents:
- Alinamin F: An active form of vitamin B1 with anti-neuritis effects.
- Methycobal: An active form of vitamin B12 that accelerates nerve cell metabolism and repairs damaged nerve fibers.
- Vitamin E: Promotes peripheral blood circulation.
3.
Sedatives: Such as Valium, Librium, and Serenal.
4.
Antivertigo Agents: The most famous is Bonamine.
5.
7% Sodium Bicarbonate 60cc IV Injection: This is commonly used for acute dizziness episodes, providing rapid symptom relief, and can be administered multiple times a day until dizziness subsides.
It is safe for pregnant women, hypertensive patients, or diabetics, with no side effects.
Patients often ask why they need to take medication continuously for three months.
This is because continuous medication for three months significantly reduces the recurrence rate, and the central nervous system's compensatory response to dizziness typically takes about three months.
The criteria for determining whether dizziness has resolved are based on the patient's subjective feelings: if there are no dizziness episodes for over three months, all previous discomfort has disappeared, and objective examinations show no abnormal eye movements, the patient can be considered cured.
Generally, peripheral dizziness can be successfully treated with three months of continuous medication, although about 30% of patients may require treatment for six months or longer.
In addition to medication, patients can also perform simple balance exercises at home.
First, have the patient open their eyes, extend their arms, and march in place for fifty steps; then close their eyes and repeat.
This should be done twice daily, observing any tilting of the body during marching to assess progress.
Some People and Events Related to Dizziness
Records of dizziness date back to ancient Greece during the time of Hippocrates, although the connection to eye movements or the inner ear was not understood.
In 1820, Czech physiologist Purkinje (the discoverer of Purkinje cells in the brain) observed that rotation could induce dizziness and rapid eye movements, attributing it to brain stimulation.
In 1824, French anatomist Flourens first discovered that damaging the anterior semicircular canals in pigeons caused them to fall forward, while damage to the posterior canals caused them to fall backward, and damage to the horizontal canals caused them to spin in place and exhibit nystagmus.
Thus, the famous "Flourens' Law" emerged, stating that each semicircular canal induces nystagmus in its respective plane: the horizontal canal induces horizontal nystagmus, the anterior canal induces rotational nystagmus, and the posterior canal induces vertical nystagmus.
He also observed that removing the brain eliminated sensory function, while removing the cerebellum resulted in loss of balance, and removing the medulla led to death.
In 1861, French physician Meniere published the famous "young girl case," where a 17-year-old girl experienced sudden dizziness accompanied by unilateral tinnitus and hearing loss, developed pneumonia on the third day, and died suddenly on the fifth day.
Meniere noted blood-like effusion in the girl's semicircular canals, suggesting that dizziness might be caused by inner ear pathology.
From a modern medical perspective, the girl likely suffered from leukemia, leading to inner ear hemorrhage, resulting in dizziness and hearing loss, rather than what we now refer to as "Meniere's disease." German physician Politzer, who listened to Meniere's lecture in Paris and returned home, also reported a similar case in 1867, attributing it to inner ear hemorrhage and naming it "Meniere's disease," thus ensuring Meniere's place in the history of neurotology.
In 1870, German Goltz published findings that damaging the semicircular canals caused dizziness.
In 1892, German Ewald published that the direction of endolymph flow is closely related to head and eye movements, proposing the famous Ewald's Law.
In 1906, Austrian Barany discovered that cold or hot stimulation of the ear canal could induce nystagmus, leading to the well-known COWS (Cold Opposite Warm Same) principle, which refers to the temperature response test—"irrigating cold water into the ear induces nystagmus toward the opposite side, while irrigating warm water induces nystagmus toward the same side." The Nobel Prize in Medicine in 1915 was awarded to Dr.
Robert Barany for proposing this convection theory of cold water rising and warm water sinking, making him the first ENT physician to receive this honor.
Retzius (1842–1919) was a Swedish tissue professor who used optical microscopy to observe inner ear tissues and illustrated the structure of the inner ear.
In 1938, Professor Yamakawa Kyoshiro from Osaka University published a pathological report on a Meniere's disease patient, who was a gynecology professor at the same university.
Yamakawa discovered endolymphatic hydrops during the autopsy, concluding that excessive endolymph production led to increased pressure in the endolymphatic space, causing dizziness, tinnitus, and hearing loss.
That same year, British Hallpike also published two similar pathological reports of endolymphatic hydrops, commemorating Meniere's initial proposal that dizziness arises from inner ear pathology, thus naming endolymphatic hydrops "Meniere's disease." In 1942, Hallpike and Fitzgerald introduced the alternating cold and warm stimulation method, proposing the concepts of canal paresis and directional preponderance.
In 1944, Cawthorne first published the labyrinth training method, although it was not widely adopted.
In the 1950s, Glorig invented ENG to record eye movement conditions.
In 1970, McCabe reintroduced the labyrinth training method, refining its steps and theoretical explanations, which is now recognized as an effective vestibular rehabilitation method.
In 1974, the visual suppression test incorporated information from the vestibulocerebellum.
In 1978, changes in head position induced the second phase of nystagmus, highlighting the involvement of the otolith organs.
In 1983, experiments from the European Space Agency's first experimental spacecraft disproved Barany's "convection theory," suggesting that thermal expansion and contraction caused volume changes, leading to dizziness and nystagmus.
Notably, historical figures in China, such as Emperor Gaozong of the Tang Dynasty, suffered from dizziness, which even allowed power to fall into the hands of Wu Zetian.
The "Records of the Three Kingdoms" mentions, "The Emperor suffered from wind, and whenever it occurred, he became disoriented and dizzy." The "Romance of the Three Kingdoms" states that Cao Cao felt dizzy two days before his death and "got up, leaned on a table, and lay down." Ming Dynasty Emperor Shenzong refrained from attending court for twenty-five years due to dizziness, and Qing Dynasty figures such as Zeng Guofan and Li Hongzhang also struggled with dizziness.

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Reply Date: 2005/05/16