Prenatal screening is not typically done for FHM, however it may be performed if requested. As penetrance is high, individuals found to carry mutations should be expected to develop signs of FHM at some point in life.

Clinical diagnosis is conducted on individuals with age onset between late teens and late forties who show the initial characteristics for the recessive autosomal cerebellar ataxia.

The following tests are performed:

- MRI brain screening for cerebellum atrophy.

- Molecular genetic testing for SYNE-1 sequence analysis.

- Electrophysiologic studies for polyneurotherapy

- Neurological examination

Prenatal diagnosis and preimplantation genetic diagnosis (PGD) can be performed to identify the mothers carrying the recessive genes for cerebellar ataxia.

Different types of ataxia:

- congenital ataxias (developmental disorders)

- ataxias with metabolic disorders

- ataxias with a DNA repair defect

- degenerative ataxias

- ataxia associated with other features.

Diagnosis of FHM is made according to the following criteria:

- Two attacks of each of the following:

- At least one close (first or second degree) relative with FHM

- No other likely cause

Sporadic forms follow the same diagnostic criteria, with the exception of family history.

In all cases, family and patient history is used for diagnosis. Brain imaging techniques, such as MRI, CAT scans and SPECT, are used to look for signs of other familial conditions such as CADASIL or mitochondrial disease, and for evidence of cerebellar degeneration. With the discovery of causative genes, genetic sequencing can also be used to verify diagnosis (though not all genetic loci are known).

Benign paroxysmal torticollis disappears in the early years of life with no medical intervention.

However, some cases of benign paroxysmal torticollis cases can evolve into benign paroxysmal vertigo of childhood, migrainous vertigo or typical migraines.

No known treatment for BPT currently exists. However, the condition it is self-limiting and resolves after about eighteen months.

The most important factor in diagnosing a patient with vertiginous epilepsy is the subject’s detailed description of the episode. However, due to the associated symptoms of the syndrome a subject may have difficulty remembering the specifics of the experience. This makes it difficult for a physician to confirm the diagnosis with absolute certainty. A questionnaire may be used to help patients, especially children, describe their symptoms. Clinicians may also consult family members for assistance in diagnosis, relying on their observations to help understand the episodes. In addition to the description of the event, neurological, physical and hematologic examinations are completed to assist in diagnosis. For proper diagnosis, an otological exam (examination of the ear) should also be completed to rule out disorders of the inner ear, which could also be responsible for manifestations of vertigo. This may include an audiological assessment and vestibular function test. During diagnosis, history-taking is essential in determining possible causes of vertiginous epilepsy as well as tracking the progress of the disorder over time.

Other means used in diagnosis of vertiginous epilepsy include:

- Electroencephalography (EEG)

- Magnetic resonance imaging (MRI)

- Positron emission tomography (PET)

- Neuropsychological testing

The EEG measures electrical activity in the brain, allowing a physician to identify any unusual patterns. While EEGs are good for identifying abnormal brain activity is it not helpful in localizing where the seizure originates because they spread so quickly across the brain. MRIs are used to look for masses or lesions in the temporal lobe of the brain, indicating possible tumors or cancer as the cause of the seizures. When using a PET scan, a physician is looking to detect abnormal blood flow and glucose metabolism in the brain, which is visible between seizures, to indicate the region of origin.

Tests of vestibular system (balance) function include electronystagmography (ENG), Videonystagmograph (VNG), rotation tests, Computerized Dynamic Posturography (CDP), and Caloric reflex test.

Tests of auditory system (hearing) function include pure-tone audiometry, speech audiometry, acoustic-reflex, electrocochleography (ECoG), otoacoustic emissions (OAE), and auditory brainstem response test (ABR; also known as BER, BSER, or BAER).

Other diagnostic tests include magnetic resonance imaging (MRI) and computerized axial tomography (CAT, or CT).

There is no known prevention of spinocerebellar ataxia. Those who are believed to be at risk can have genetic sequencing of known SCA loci performed to confirm inheritance of the disorder.

The diagnosis of TRAPS may show an increased IgD level in a possibly affected individual, other methods to ascertain a definite finding is via the following:

- Blood test

- Genetic test

- Clinical evaluation

Since lateral medullary syndrome is often caused by a stroke, diagnosis is time dependent. Diagnosis is usually done by assessing vestibular-related symptoms in order to determine where in the medulla that the infarction has occurred. Head Impulsive Nystagmus Test of Skew (HINTS) examination of oculomotor function is often performed, along with computed tomography (CT) or magnetic resonance imaging (MRI) to assist in stroke detection. Standard stroke assessment must be done to rule out a concussion or other head trauma.

Supportive treatment is the only intervention for acute cerebellar ataxia of childhood. Symptoms may last as long as 2 or 3 months.

Acute Cerebellar ataxia is a diagnosis of exclusion. Urgent CT scan is necessary to rule out cerebellar tumor or hemorrhage as cause of the ataxia; however in acute cerebellar ataxia, the CT will be normal. CSF studies are normal earlier in the course of disease. Later on CSF shows moderate elevation of proteins.

SPS is diagnosed by evaluating clinical findings and excluding other conditions. There is no specific laboratory test that confirms its presence. Underdiagnosis and misdiagnosis are common.

The presence of antibodies against GAD is the best indication of the condition that can be detected by blood and cerebrospinal fluid (CSF) testing. Anti-GAD65 is found in about 80 percent of SPS patients. Anti-thyroid, anti-intrinsic factor, anti-nuclear, anti-RNP, and anti-gliadin are also often present in blood tests. Electromyography (EMG) demonstrates involuntary motor unit firing in SPS patients. EMG can confirm the diagnosis by noting spasms in distant muscles as a result of subnoxious stimulation of cutaneous or mixed nerves. Responsiveness to diazepam helps confirm that the patient is suffering from SPS, as this decreases stiffness and motor unit potential firing.

The same general criteria are used to diagnose paraneoplastic SPS as the normal form of the condition. Once SPS is diagnosed, poor response to conventional therapies and the presence of cancer indicate that it may be paraneoplastic. CT scans are indicated for SPS patients who respond poorly to therapy to determine if this is the case.

A variety of conditions have similar symptoms to SPS, including myelopathies, dystonias, spinocerebellar degenerations, primary lateral sclerosis, neuromyotonia, and some psychogenic disorders. Tetanus, neuroleptic malignant syndrome, malignant hyperpyrexia, chronic spinal interneuronitis, serotonin syndrome, Multiple sclerosis, Parkinson's disease, and Isaacs syndrome should also be excluded.

Patients' fears and phobias often incorrectly lead doctors to think their symptoms are psychogenic, and they are sometimes suspected of malingering. It takes an average of six years after the onset of symptoms before the disease is diagnosed.

The difficulty of making the right vestibular diagnosis is reflected in the fact that in some populations, more than one third of the patients with a vestibular disease consult more than one physician – in some cases up to more than fifteen.

Diagnosis of a balance disorder is complicated because there are many kinds of balance disorders and because other medical conditions—including ear infections, blood pressure changes, and some vision problems—and some medications may contribute to a balance disorder. A person experiencing dizziness should see a physiotherapist or physician for an evaluation. A physician can assess for a medical disorder, such as a stroke or infection, if indicated. A physiotherapist can assess balance or a dizziness disorder and provide specific treatment.

The primary physician may request the opinion of an otolaryngologist to help evaluate a balance problem. An otolaryngologist is a physician/surgeon who specializes in diseases and disorders of the ear, nose, throat, head, and neck, sometimes with expertise in balance disorders. He or she will usually obtain a detailed medical history and perform a physical examination to start to sort out possible causes of the balance disorder. The physician may require tests and make additional referrals to assess the cause and extent of the disruption of balance. The kinds of tests needed will vary based on the patient's symptoms and health status. Because there are so many variables, not all patients will require every test.

Depending on subtype, many patients find that acetazolamide therapy is useful in preventing attacks. In some cases, persistent attacks result in tendon shortening, for which surgery is required.

Prenatal screening is not typically done for FHM, however it may be performed if requested. As penetrance is high, individuals found to carry mutations should be expected to develop signs of FHM at some point in life.

There is currently no cure for SCA 6; however, there are supportive treatments that may be useful in managing symptoms.

The condition is diagnosed by the patient's history, and by performing the Dix–Hallpike test or the roll test, or both.

The Dix–Hallpike test is a common test performed by examiners to determine whether the posterior semicircular canal is involved. It involves a reorientation of the head to align the posterior semicircular canal (at its entrance to the ampulla) with the direction of gravity. This test will reproduce vertigo and nystagmus characteristic of posterior canal BPPV.

When performing the Dix–Hallpike test, patients are lowered quickly to a supine position, with the neck extended by the clinician performing the maneuver. For some patients, this maneuver may not be indicated, and a modification may be needed that also targets the posterior semicircular canal. Such patients include those who are too anxious about eliciting the uncomfortable symptoms of vertigo, and those who may not have the range of motion necessary to comfortably be in a supine position. The modification involves the patient moving from a seated position to side-lying "without" their head extending off the examination table, such as with Dix–Hallpike. The head is rotated 45 degrees away from the side being tested, and the eyes are examined for nystagmus. A positive test is indicated by patient report of a reproduction of vertigo and clinician observation of nystagmus. Both the Dix–Hallpike and the side-lying testing position have yielded similar results, and as such the side-lying position can be used if the Dix–Hallpike cannot be performed easily.

The roll test can determine whether the horizontal semicircular canal is involved. The roll test requires the patient to be in a supine position with their head in 30° of cervical flexion. Then the examiner quickly rotates the head 90° to the left side, and checks for vertigo and nystagmus. This is followed by gently bringing the head back to the starting position. The examiner then quickly rotates the head 90° to the right side, and checks again for vertigo and nystagmus. In this roll test, the patient may experience vertigo and nystagmus on both sides, but rotating towards the affected side will trigger a more intense vertigo. Similarly, when the head is rotated towards the affected side, the nystagmus will beat towards the ground and be more intense.

As mentioned above, both the Dix–Hallpike and roll test provoke the signs and symptoms in subjects suffering from archetypal BPPV. The signs and symptoms patients with BPPV experience are typically a short-lived vertigo, and observed nystagmus. In some patients, though rarely, the vertigo can persist for years. Assessment of BPPV is best done by a medical health professional skilled in management of dizziness disorders, commonly a physiotherapist, audiologist or other physician.

The nystagmus associated with BPPV has several important characteristics which differentiate it from other types of nystagmus.

- Latency of onset: there is a 5–10 second delay prior to onset of nystagmus.

- Nystagmus lasts for 5–120 seconds.

- Positional: the nystagmus occurs only in certain positions.

- Repeated stimulation, including via Dix–Hallpike maneuvers, cause the nystagmus to fatigue or disappear temporarily.

- Rotatory/Torsional component is present, or (in the case of lateral canal involvement) the nystagmus beats in either a geotropic (towards the ground) or ageotropic (away from the ground) fashion.

- Visual fixation suppresses nystagmus due to BPPV.

Although rare, CNS disorders can sometimes present as BPPV. A practitioner should be aware that if a patient whose symptoms are consistent with BPPV, but does not show improvement or resolution after undergoing different particle repositioning maneuvers — detailed in the Treatment section below — need to have a detailed neurological assessment and imaging performed to help identify the pathological condition.

"See the equivalent section in the main migraine article."

People with FHM are encouraged to avoid activities that may trigger their attacks. Minor head trauma is a common attack precipitant, so FHM sufferers should avoid contact sports. Acetazolamide or standard drugs are often used to treat attacks, though those leading to vasoconstriction should be avoided due to the risk of stroke.

Unfortunately, there is no real way to prevent against vertiginous episodes out of the means of managing the disease. As head trauma is a major cause for vertiginous epilepsy, protecting the head from injury is an easy way to avoid possible onset of these seizures. With recent advances in science it is also possible for an individual to receive genetic screening, but this only tells if the subject is predisposed to developing the condition and will not aid in preventing the disease.

There is a range of ways to manage vertiginous epilepsy depending on the severity of the seizures. For simple partial seizures medical treatment is not always necessary. To the comfort of the patient, someone ailed with this disease may be able to lead a relatively normal life with vertiginous seizures. If, however, the seizures become too much to handle, antiepileptic medication can be administered as the first line of treatment. There are several different types of medication on the market to deter epileptic episodes but there is no support to show that one medication is more effective than another. In fact, research has shown that simple partial seizures do not usually respond well to medication, leaving the patient to self-manage their symptoms. A third option for treatment, used only in extreme cases when seizure symptoms disrupt daily life, is surgery wherein the surgeon will remove the epileptic region.

Episodic ataxia (EA) is an autosomal dominant disorder characterized by sporadic bouts of ataxia (severe discoordination) with or without myokymia (continuous muscle movement). There are seven types recognised but the majority are due to two recognized entities. Ataxia can be provoked by stress, startle, or heavy exertion such as exercise. Symptoms can first appear in infancy. There are at least 6 loci for EA, of which 4 are known genes. Some patients with EA also have migraine or progressive cerebellar degenerative disorders, symptomatic of either familial hemiplegic migraine or spinocerebellar ataxia. Some patients respond to acetazolamide though others do not.

Diagnosis consists of a variety of tests, including but not limited to:

- Measurement of orthostatic blood pressure

- Coordination

- rapid, alternating movements

- stroking of heel from along the opposite shin from knee to ankle

- finger-to-nose testing.

- Primary sensory modalities are examined with the following methods, searching for focal sensory loss, graded distal sensory loss, or levels of decreased sensation, hyperesthesia or dysesthesia.

- light touch

- pin-prick

- temperature

- position

- vibration

- Focused gait examination, which examines stationary position and walking abnormalities. Walking generally exposes any faults within the complex neurological communication between systems as weight is shifted from one foot to the other.

Treatment consists of physical rehabilitation programs designed to improve overall function, increase strength and improve balance. The ultimate goal is to increase the patient's degree of independence, thus improving the patient's quality of life. Exercise typically begins with simple movements, gradually transitioning into more complex actions. Various aspects of treatment are assessed based on the individual patient's condition, utilizing many assessment tools:

- Functional Reach Test

- External Perturbation Test – Push, Release

- External Perturbation Test – Pull

- Clinical Sensory Integration Test

- Single Leg Stance Test

- Five Times Sit to Stand Test

Various scales are also utilized

- Brief Ataxia Rating Scale

- Friedreich's Ataxia Impact Scale

- Scale For Assessment and Rating of Ataxia

The outlook for someone with lateral medullary syndrome depends upon the size and location of the area of the brain stem damaged by the stroke. Some individuals may see a decrease in their symptoms within weeks or months. Others may be left with significant neurological disabilities for years after the initial symptoms appeared. However, more than 85% of patients have seen minimal symptoms present at six months from the time of the originatl stroke, and have been able to independently accomplish average daily within a year.