This document discusses thalamic syndromes and their clinical presentations. It summarizes: 1) Thalamic syndromes can cause sensory disorders, disorders of consciousness, and motor disorders depending on the affected thalamic nucleus. 2) The clinical vignette describes a patient with a thalamic pain syndrome called Dejerine-Roussy disease, caused by an infarct in the posterolateral thalamus. 3) Characteristics of thalamic pain syndrome include contralateral sensory loss, paresthesia, intractable pain unresponsive to analgesics, and abnormal posture of the hand called the "thalamic hand."

1. Applied Anatomy of Thalamus
Dr. Mathew Joseph MBBS,BCC(Palliative Medicine)
Junior Resident (MD)
Department of Anatomy
All India Institute of Medical Sciences, Rishikesh

2. Clinical Vignette
A 65 year old alcoholic man was brought to
emergency department following an attack of
intractable pain over both right extremities which
was not relieved by strong analgesics. Clinical
history reveals that he is on antihypertensive drugs
since 20 years and had an ischemic stroke in brain
recently. On examination his right upper limb was in
abnormal posture resembling rheumatoid arthritis,
but which was appeared in a span of few days. His
MRI reveals the following picture. How could you
comment on the above scenario.

4. Thalamic Syndromes
• Postero-Lateral Thalamic Syndromes(Thalamic Syndrome)
: Sensory disorders
: Ventro Posterior Nucleus
• Medial Thalamic Syndromes(Disorders of Consciousness)
: Thalamic neglect
:Thalamic Mutism
:Thalamic Amnesia
• Antero-Lateral Thalamic Syndromes(Motor disorders)
:Paresis
:Ataxia
:Dysphagia
:Motor incordination

5. Thalamic Syndrome
• "Dejerine-Roussy disease”(Joseph Jules Dejerine
& Gustave Roussy)
• Thalamic Pain Syndrome
• (Post Stroke) Central Pain Syndrome(CPS)
• Retrolenticular Stroke Syndrome

6. Thalamic Syndrome
• Infarct in Geniculothalamic
(thalamogeniculate, posterolateral) artery, a
branch of the posterior cerebral artery.
• Involves : Posteroventral and Posterolateral
nuclei.

7. • Hallmark signs :
Pansensory loss contralateral to the lesion
Paresthesia
Thalamic pain
Transient hemiparesis
Homonymous hemianopsia
Hemiataxia
Tremor
Choreiform movements
Spatial neglect
****All contralateral to the lesion in the thalamus

8. Thalamic Pain
• Threshold of Touch, Pain and Temperature is
decreased(C/L)
• Cutaneous stimuli trigger paroxysmal exacerbations of
the pain that outlast the stimulus.
• Perception of “epicritic” pain (from a pinprick) is
reduced on the painful areas.
• aka Anesthesia dolorosa, or Painful anesthesia
• Sponteneous and intractable pain : Fail to respond to
powerful analgesics.

9. Frontal lobotomy
• To relieve intractable pain.
• Dividing dorsal nuclei of thalamus from the
frontal lobe.

10. Thalamic Hand

11. Thalamic Hand
• Contrlateral hand : Abnormal posture
Forearm: Pronation
Wrist : Flexed
Metacarpophalengeal joints : Flexed
Interphalangeal joints: Extended
Fingers may be abducted
Thumb is either abducted or pushed against the palm.
• *** fingers can be moved slowly due to altered muscle tone
in different muscle groups.is flexed and pronated at the wrist
and metacarpo-phalangeal joints and extended at the
interphalangeal joints.

12. Thalamic hand & Corresponding MRI

13. Korsakoff’s syndrome
• Chronic memory disorder
• Thiamine deficiency due to Alcoholism
• Difficulty in remembering new information.
• Involves lesions of Mediodorsal nucleus of
thalamus.
• Assosiated with Korsakoff’s Psychosis

14. Thalamic Cauterization
• Surgical pain relief method
• The intralaminar nuclei of the thalamus are known to
take part in the relay of pain to the cerebral cortex.
• Cauterization of these nuclei has been shown to
relieve severe and intractable pain associated with
terminal cancer.