It is not my intention  to give a lesson on dizziness but to shed some light on this symptom which represents 5% of visits to doctors.
Under this generic term, patients describe all sorts of things and to know how to detect the the nature of the symptom and its cause requires rigourous questionning of the patients and study of the clinical examinations.
On the other hand too many patients equate dizziness and Menire vertigo whereas Meniere disease is a symptom of vertigo.

DEFINITION
Vertigo can be defined by the erroneous sensation of moving objects with respect to the subject or the subject in relation to objects, also ocular signs called NYSTAGMUS.

There can be many forms of vertigo.
Rotary sensation
Tendency to fall on one's side
Unsteadiness or pitching

Installation
Sudden or gradual

Duration of vertigo
Several hours to several days

Evolutionary mode
Permanent and chronic attacks
precipitating factors to look for:

Stress, fatigue, change of position, excess of salt or even food intake.

Associated signs:
Having the feeling that the ear is blocked
Tinnitus or deafness
Nausea, vomiting, sweating, migraines, headaches.

Clinical context
Trauma history
Recent medication (antibiotics, neurological)
General pathology: Background: infectious or oncological context

Neurotonic psychological profile or situation of great stress (bereavement, divorce, moving of home)

Other reasons for feeling 'dizzy':
Dizzy heights (vertigo)
Drop of blood pressure
Syncope
Feeling faint due to anemia

THE MAIN CAUSES OF DIZZINESS

1)     The Meniere disease

This diagnosis is often given when it should not be. Too many patients are diagnosed with this without having had a thorough examination. Vertigo attacks and the Meniere disease are too often assimilated.
It is actually a labyrinthine hydrops. That is to say an IOP phenomen distending the membranous labyrinth of the inner ear.

Clinical signs:
Dizziness can be any type of Tinnitus with the feeling of having a blocked ear.
Fluctuating loss of hearing.
 Sudden attacks that stabilize but changes in hearing are pejorative and end up by getting back to normal. We are unable to predict how the hearing will deteriorate.
There is often a particular psychological profile or a stressful situation (family or professional).

The audiogram is often characteristical with an upward curve.
The treatment of Meniere disease is medical.
Vestibuloplegique, anxiolytic, antioedemateux.
Apsychological treatment may be necessary.

In all the Meniere disease is diagnosed after study of clinical evidence and its progress is unpredictable especially as far as hearing is concerned.

2) Benign positional paroxysmal vertigo (BPPV)

The attack.

Typical, stereotyped, usually at night, the patient feels dizzy and anxious each time he or she changes position in bed.
The actual attack only lasts a few seconds. Most important there are no auditory signs. Patients often speak of 'crystals' in the ear. It is actually a deposit of otoclonies at the posterior semicircular canal.
If untreated the attacks can continue for 15 days although decreasing in intensity and ending up by disappearing completely. However relapses may occur several months later.
Treatment is based on the Hallpike maneuver which is manipulating the patient.
Physiotherapy can speed up the recovery.
Its evolution is favourable.

3)     Post traumatic vertigo


Fractured bones.


The clinical context is evident. Dizziness disappears quickly after CCP clearing.

Labyrinthine concussion:

In this case there is no detectable bone lesion but the patient complains of dizziness or loss of hearing following head injury and although hearing improves rapidly the dizziness does not.  The dizziness can disappear quickly or on the contrary last several months and the problem is to link it to the trauma.

4) Baro-trauma vertigo.

    Vertigo after diving.

5) Vestibular neuritis.
A viral accident:
In this case the vertigo is intense accompanied by nausea and vomiting. The patient is confined to bed and does not move.
Still no signs of hearing.
The attack often lasts the entire day and the patient who is in a precarious state, can only be seen the next day.
Normal activity can be resumed after a week but the feeling of imbalance may persist for some time.
Despite the spectactular nature of the attack evolution is always positive.

6) Neuroma du VIII
        Vertigo is rarely indicative of Neuroma; the most important sign is unilateral deafness.

        Rare causes

Tumor of the rock, vasulaire accident, otosclerosis, toxic damage to the ear because of drug usage ( antibiotics), alcohol intoxication, brain tumor or cerebellar.