Board Review – Neurology 1

Pragya Verma

PGY – 3

Morehouse School Of Medicine

Ataxia • It is the inability to make smooth, accurate and coordinated movements.

• The location is typically cerebellum and / or sensory pathways in the posterior columns of the spinal cord.

• Primarily affects the gait, but can be generalized as well.

• Below are the common causes of Acute Ataxia

Trauma Infectious Metabolic Malignancy Toxic

• Hematoma• Post Concussion• Cerebellar Hemorrhage• Kawasaki Disease

• Acute Post infectious Cerebellar Ataxia• Cerebellar Abscess• Acute Labyrinthitis•Encephalitis of Brain Stem• Multiple Sclerosis• Miller Fischer Sundrome

• Hartnup Disease• Maple Syrup Urine Disease• Pyruvate de - hydrogenase deficiency

• Neuro blastoma• Tumors of the cerebellum and frontal lobe as well.

• Phenytoin • Alcohol• Thallium (Pesticide)

Content Spec – Know the common causes of Acute Ataxia

AtaxiaChronic and Progressive Ataxia

Joubert Syndrome:• Autosomal Recessive• Agenesis of the Cerebellar Vermis• Presents in infancy as hypotonia, delayed milestones, truncal ataxia and neonatal breathing problems.• Associated with the Molar Tooth Sign on MRI.

Arnold Chiari malformation and Dandi walker syndrome.

AtaxiaChronic and Progressive AtaxiaDegenerative Diseases Ataxia – Telangiectasia

• Autosomal Recessive Condition• Ataxia begins at the age of 2 years and progresses to loss of ambulation by

adolescence. • Associated with telangiectasia over the bridge of the nose and ears, reduced Ig A and

Ig G levels and increase frequency of Leukemia, Lymphomas.

AtaxiaChronic and Progressive AtaxiaFriedreich Ataxia

• Autosomal Recessive• Onset is later than AT but usually before 10 years of age. • Explosive Dysarthric Speech and Nystagmus, Skeletal abnormalities and

Hypertrophic Cardiomyopathy.• Associated with more than 90 GAA repeat expansion in the Frataxin gene. Mutations

cause oxidative injury associated with increase iron deposits in the mitochondria.

Spinocerebellar Ataxia 1, 2, 3 and 7 area all autosomal dominant.

AtaxiaEvaluation of Ataxia should be systematic and the following points may be helpful

• Anatomical Localization : Is the problem at the level of the brain, brain stem, spinal cord, ant horn cell, ant root, nerve, Neuromuscular Junction or the muscle?

• In Ataxia the symptoms will help us to evaluate if it is the cerebellum alone or it

involves other levels of the nervous system.

• Time course – Acute Vs Chronic and Static Vs Progressive over time.

• Identification of the inheritance pattern. Autosomal Recessive Vs Autosomal Dominant. X inked or maternal Mitochondrial inheritance. Eg: Absence of the autosomal dominant pattern reduces the likelihood of spino cerebellar ataxias.

• Identification of involvement of other body systems ie: Eye , Skin , Skeletal or Cardiac findings

• Genetic testing can also be performed but Neurology consult can be less expensive and lead to less lab/imaging evaluations.

Content Spec – Know the evaluation of Ataxia

Acute Cerebellar Ataxia• An infectious cause for acute onset of Ataxia.• Occurs in children between 1-3 years of age.• Occurs 2 – 3 weeks after an exposure to a viral illness – varicella, coxsackie virus or

echovirus and is thought to be an auto immune type of process.• Truncal Ataxia and it can be so severe that the child is unable to stand or sit.

Horizontal nystagmus and dysarthria are present as well.• Importantly, fever, nuchal rigidity are absent. Vomiting may be present. • It is a diagnosis of exclusion and brain imaging and CSF analysis are normal. CSF

may show increasing protein on a repeat tap.• Most Importantly, the prognosis is excellent and ataxia begins to improve in a few

weeks. Recovery typically happens by 2 months. • No treatment is typically required. OT, PT may be helpful.• DDx – Acute Labyrinthitis – Associated with middle ear infections, intense vertigo,

vomiting and abnormalities in labyrinthine functions.

http://www.youtube.com/watch?v=5Dj827uCP3g

Content Spec – Know the prognosis of childhood Acute Cerebellar Ataxia

Vertigo

Content Spec – Know the common causes of Vertigo

Vertigo is defined as any illusion or sensation of motion.

Younger children may express the dysequilibrium only by falling, stumbling or clumsiness. Older children may describe a feeling of room spinning or turning.

Question - 1

Question - 2

Transverse Myelitis• Abrupt onset of progressive weakness and sensory disturbances in the lower

extremities.• A history of fever and malaise is typically documented. The viruses implicated are

EBV, Herpes, Influenza, Rubella, Mumps, Varicella, HIV, Mycoplasma.• TM can also occur with autoimmune diseases such as SLE, antiphospholipid

antibody syndrome, sarcoidosis, Sjogren syndrome, and mixed connective tissue disease. Of patients presenting with TM, 5% to 10%develop multiple sclerosis.

• It is hypothesized that it is either a direct viral invasion, cell mediated auto immune response or autoimmune vasculitis.

• Symptoms consist of motor , sensory symptoms depending on the level of the cord involved. Typically they include –

Low Back Pain

Sensory – Paresthesias of the legs, Pain, Temp and Light Sensations are affected, A sensory level is present in the mid-thoracic region. Joint position and vibration may be preserved.

Motor – The leg muscles are weak and flaccid.

Sphincter disturbances are common.

Transverse MyelitisWORK UP & TREATMENT OF

TMAcute treatment of TM • High-dose pulse steroids (usually 1

g methylprednisolone IV for 5 d)

• Plasmapheresis may be used if patients do not respond to steroids.

• If TM occurs in association with an underlying disease, other specific therapies may be indicated.

• Acyclovir for HSV infection, ganciclovir for CMV infection, cyclophosphamide for SLE.

• Approximately 33% of patients recover with little or no sequelae, 33% suffer moderate permanent disability, and 33% have virtually no recovery and are left with severe disability.

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TM

Spine MRI

Non Compressive

Lesion

Compressive Lesion

• CSF• Viral PCR, Lyme Ab• VDRL• Mycoplasma Ab • Oligoclonal Bands

• Serological • HIV• Lyme titers• Mycoplasma• Hepatitis • Autoimmune-ANA, Rf, Anti DNA

• EMG• EvokedPotential

Content Spec – Plan the evaluation in a patient in whom post infectious myelitis is suspected

Brain MRI with Gadolinium Demyelinating lesions in the brain - multiple sclerosis

Transverse Myelitis

Acute Spinal Cord LesionClinical Manifestations of Spinal Cord Injuries or Lesions(Infectious or Tumors)• Severe cord Injury presents with spinal shock.• Sensory – Loss of sensations below the level of the injury• Motor – Muscle Weakness, Flaccidity, Loss of Reflexes.• Sphincter weakness, loss of bowel and bladder control.• Autonomic signs such as Hypotension and Bradycardia.• Respiratory failure can occur due to high cervical spine lesions affecting the phrenic

nerve to diaphragm function.• Recovery signs include Reflex Flexor activity followed by Reflex Extensor Activity

associated with Hyperactive Deep Tendon Reflexes, Spasticity and Automatic Bladder.

• Mild Concussion of the cord will result in transient quadriparesis for seconds or minutes with full recovery in 24 hours.

• Conus Medullaris Syndrome – Loss of Urinary and rectal sphincter, flaccid weakness and sensory loss in the legs.

• Central Cord Lesion – Involves Upper extremities more than the Lower extremities.• Anterior spinal artery stroke – Weakness in the lower ext and loss of pain and

temperature with preservation of vibratory and proprioceptive sensation.

Content Spec – Clinical manifestations of an acute spinal cord lesion, bladder An d bowel dysfunction

Evaluation and Treatment• Spinal Cord injury is a Neurological emergency. • The initial diagnostic emphasis should be directed toward localizing the proper level

of the nervous system: brain, brainstem/cerebellum, spinal cord, nerve, junction, or muscle. Urgent phone or in-person consultation with a neurologist or neurosurgeon can be useful before ordering testing.

The back pain, acute bilateral flaccid weakness, and sensory loss below the level of the lesion localize the problem to the spinal cord.

• Based on the history and examination findings, magnetic resonance imaging (MRI) of the spine is the test of choice. This should aid in determining the specific location of the lesion and whether emergency neurosurgery to decompress the spinal cord is needed.

• A subsequent lumbar puncture also may help identify the cause of the patient's symptoms, but it may not be necessary and should not delay obtaining the spine MRI. Lumbar puncture is also helpful for identifying inflammatory causes of spinal cord disease.

• Somato-sensory evoked potentials are neurophysiologic tests that document the integrity of sensory pathways from peripheral nerves through the spinal cord to the brain.

Content Spec – Neurodiagnostic evaluation of patient with acute spinal cord dysfunction

Down Syndrome and Neuro• Susceptible to Atlanto – Axial Instability due to laxity of the transverse ligament.• Measurements of less than 5 mm are normal, 5 to 7 mm indicate instability, and more

than 7 mm are markedly abnormal according to AAP guidelines for DS.• Spinal cord compression may result with Sx of urinary and bowel incontinence,

weakness, spasticity, gait issues, and sensory loss.• Current Recommendations are lateral XR of the neck in neutral, flexion and extension

positions at 3- 5 years of age and at a later age if indicated as it can develop during periods of growth.

• However there is a lack of consensus -  First, individuals who have DS and normal findings on screening may have abnormal radiographic results later in childhood. Conversely, some individuals whose study results initially are abnormal eventually have normalized results.

• Finally, several publications report that individuals who have DS and AAI and symptoms or signs of cervical cord compression rarely present with rapid decompensation.

• Physical examination findings suggestive of spinal cord compression may be more predictive of significant spinal cord injury than plain radiographs, and it is wise for all individuals who have DS to undergo a careful neurologic examination prior to sports participation.

Content Spec – Atlanto axial in Down Sundrome and Neurological Complications

Thank You