Tremor : an update · 2020. 11. 19. · tremor for 1 yr. Strong Fam. Hx Action tremor in the head,...
Transcript of Tremor : an update · 2020. 11. 19. · tremor for 1 yr. Strong Fam. Hx Action tremor in the head,...
I
Tremor : an update
Prof. Kailash Bhatia
Institute of Neurology,
Queen Square,
London
MDJ- 2018
MDS Consensus Criteria for ET (Deuschl et al.1998) • Inclusion:
Bilateral, largely symmetrical postural or
kinetic tremor involving hands and forearms
that is visible and persistent
Additional (or isolated ! ) tremor of the head
may occur but without abnormal posturing
MDS Consensus Criteria for ET
• Exclusion criteria include:
Other signs, especially dystonia
Isolated position-specific
or task-specific tremor
ET has been considered as a pure or
monosymptomatic disorder but….
ET literature (and dystonia)
• Database of 350 pts with “ET”
• 47% of patients had associated dystonia
(Spasmodic Torticollis in 27%, Writers Cramp
in 14%, blepharospasm 7%, Spasmodic
Dysphonia 4%)
20% developed parkinsonism (after ET)
• ‘‘This analysis finds no support for differentiation of ET subtypes and
it suggests that ET, although heterogenous in its clinical presentation,
is a single disease entity.”
Lou & Jankovic,
Other features reported for ET
• Cerebellar dysfunction
• Cognitive changes- Duane et al , 2002, Higginson et al,
2008);- not controlled for depression, anxiety, co-
morbidities, medications, etc
• Olfaction: affected -Louis et al 2002 –however not found
in other studies (Shah et al); may be related to co-
morbidities or specific subgroup
• Hearing loss: Ondo et al, -but age dependent rather then
tremor severity dependent, age related?
Misdiagnosis of ET
What conditions are commonly mistaken
for ET and vice versa?
• Enhanced physiological tremor
• Tremulous dystonia or dystonic tremor
• PD, especially “BTP”
• Misdiagnosis rate of ET in 2 studies 37% (Jain et
al, 2007) and 50% (Schrag et al, 2000)
Dystonia in ET was reported in between 7- 47% in various studies
The definition of tremor has not changed
• An involuntary, rhythmic, oscillatory movement of a body part
• Problem: the only perfectly rhythmic tremor is primary orthostatic tremor
How rhythmic must an
oscillation be?
The concept of “isolated” and
“combined” tremor
Examples of Axis 1 classification
Essential tremor
Combined tremor syndromes
Isolated tremor syndromes
Dystonic tremor
Task-specific tremor
Primary orthostatic tremor
Rest tremor Bradykinesia
Rigidity
Tremor with ataxia
ET is a syndrome with multiple
etiologies.
• There is genetic heterogeneity.
• Many cases appear to be sporadic.
• It is an early phenotype of hereditary dystonia (eg, ANO3), hereditary ataxia (eg, SCA12), and Parkinson disease.
Louis. Arch Neurol 2009; 66: 1202-8
Deuschl et al. Mov Disord 2015; 30: 1327-34
Choudhury et al. Mov Disord Clin Pract 2018; 5: 39-46
Stamelou et al. Mov Disord 2014; 29: 928-934
ET plus “soft signs”
1. Rest tremor or questionable rest tremor
2. Impaired tandem gait
3. Questionable dystonic posturing of the hands, head, etc.
4. Memory impairment
5. Mild sensory neuropathy
6. Markedly asymmetric upper limb tremor
7. Jerky tremor
Strongly
discouraged.
Tremor Investigation Group (TRIG) 1990
Validity of subtle (soft)
signs of dystonia?
Courtesy
Roger Elble
ET plus is more common than
ET? Cohort of patients with lower limb tremor
Rajalingam et al. Parkinsonism Relat Disord 2018; 56: 109-110
A 69 year old man with a 10 year history of worsening tremor – possible
family history in mother late in her life – mild benefit with alcohol
Clinical example
Isolated
bilateral upper
extremity
tremor for 1
yr.
Strong Fam.
Hx
Action tremor
in the head,
voice and
upper limbs
Increased
tremor
Strained voice
Slight head tilt
Increased
tremor
Strained voice
Cervical
dystonia
ANO3
mutation
2 yr 3 yr 1 yr
Indeterminate
tremor ET ET plus
Antecedent
ET Antecedent
ET
ANO3
dystonia
Dystonic
tremor
syndrome
Stamelou et al. Mov Disord 2014; 29: 928-934.
Idiopathic
Familial
Idiopathic
Familial
Idiopathic
Familial
2 yr 3 yr 1 yr
Axis
1
Axis
2
Axis 1 classifications may change.
Clinical syndrome – Possible Essential tremor – but genetic diagnosis
DYT2 (HPCA gene mutations)
Axis 1 subtypes – more etiologic
specificity?
Data from one subtype may not be generalizable to other subtypes.
Management of Essential tremor
syndromes
Drugs :
• Propranolol
• Primidone
• Topirimate
Botulinum toxin injections:
Functional neurosurgery:
- VIM DBS
- Thalamic lesioning
- Focussed ultrasound
NEJM
2016
Orthostatic tremor- may be difficult to
visualise as very fast – but you could listen to
it!
Rubral tremor
70 year old with a 25 year history of postural tremor and more recent gait
disorder, cognitive problems, MRI shows some cerebellar atrophy
MDJ 2020 in press
Concluding remarks • New classification will help with :
• Effect of drugs such as propranolol, primidone
and others in different tremor syndromes
• And whether different targets should be
considered for DBS in ET syndrome versus DT
syndrome for example
• What about anticholinergics in ET plus with
dystonia?
• Outcomes and prognosis may differ