Jeffrey Mann's Central/Peripheral Vertigo Table
            ===============================================

CLINICAL FEATURES       PERIPHERAL VERTIGO              CENTRAL VERTIGO

Intensity of vertigo    moderate to intense             mild to moderate

Autonomic symptoms      prominent and often worse       less common
(nausea, vomiting,      when moving the head
sweating)

Nystagmus: (direction of the fast phase)

Type                    horizontal or rotatory          horizontal or rotatory
                        jerk-type                       or vertical or
                                                        asymmetric or bizarre

Clinical features       Decreases or ceases             Unaffected or little
                        when visually fixating.         affected by fixation.
                        Increases in intensity          Increased intensity
                        when the gaze is in the         when covering the
                        direction of the fast phase.    fixating eye.
                                                        Increased intensity when
                                                        covering the fixating
                                                        eye.
                        Directionally fixed in
                        all directions.
                                                        May change direction
                        gaze directions.                in different gaze
                                                        directions
NB:
1. Nystagmus always increases when eyes are turned away from the fast phase
(toward the slow phase): Alexander's Law.
2. Fixation is totally removed by applying Frenzel glasses that prevent
fixation but allow visualization of nystagmus, may also look in one eye with
ophthalmoscope and cover the other eye.
Nystagmus only present  Yes                             No
in the dark

Nystagmus present when  No                              Yes
fixating

Features on Nylen-      Has latentcy, fatigues and      No latentcy or
Barany testing          adapts.                         fatiguing. Does not
(Hallpike manuver)                                      adapt.

Otological symptoms     may be present                  usually absent

Risk factors for stroke may be absent                   usually present
                                                        - hypertension, smoking,
                                                        DM, vascular disease

Neurological symptoms   usually absent                  may be present
                                                        - headache, face pain
                                                          or paresthesias
                                                        - blurred/double vision

Neurological signs      absent                          may be present
                                                        - cranial nerve deficits
                                                        - dysarthria, dysphagia
                                                        - dysmmetria
                                                        - Horner's syndrome
                                                        - face/limb sensorimotor
                                                          deficits
                                                        - diplopia

Gait                    possible, but tends to          near-impossible &
                        lean or fall towards one side   very uncoordinated
                                                        & falls to any side.

                        preserved walking - but         Falls when walking
                        unidirectional postural         and cannot even
                        instability.                    ambulate.

Definite indications for immediate neuro-imaging in acute vertigo
include:-

1) Acute sudden headache.
2) Inability to ambulate.
3) Horizontal spontaneous nystagmus that changes directions with gaze.
4) Vertical spontaneous or positional nystagmus.
5) Any focal neuro signs.

--Jeffrey Mann, adapted from "Acute vestibular sydrome," NEJM - September 3 1998