Lewy Body Dementia

Question 1

The primary distinguishing factor between LBD and PDD

Answer 1

The duration of the cognitive symptoms and their time of onset in relation to parkinsonism

Question 2

Patients with LBD usually have onset of cognitive symtpoms and parkinsonian symptoms . . .

Answer 2

. . . simultaneously and within one year of disease onset

Question 3

Features of PSP

Answer 3

• Parkinsonism
• Vertical gaze palsy
• Axial rigidity
• Postural instability
• Subcortical dementia

Question 4

Features of CBD

Answer 4

• Parkinsonism
• Dementia with cortical and subcortical features
• Alien limb phenomenon

Question 5

Normal pressure hydrocephalus as a mimic of LBD

Answer 5

Early in disease, both may have mild parkinsonism, subcortical dementia, gait disturbance, and urinary symptoms

They can be distinguished by neuroimaging and assessment of response to large volume lumbar puncture (removal of ~30-40 mL of CSF)

Question 6

RBD is a pathologic hallmark of all ___ diseases

Answer 6

RBD is a pathologic hallmark of all Lewy body diseases

ie, PD, MSA, and LBD

Question 7

Central and Core features of LBD

Answer 7

• Central (required for diagnosis):
  
  • Presence of dementia
• Core (two required for diagnosis, one required for ‘possible’ LBD):
  
  • Fluctuations in cognition with pronounced variation in attention and alertness
  • Recurrent visual hallucinations that are typically well formed and detailed
  • Spontaneous features of parkinsonism

Question 8

Patients with LBD exhibit profound sensitivity to ___

Answer 8

Patients with LBD exhibit profound sensitivity to neuroleptics

Question 9

Pattern of cognitive impairment in LBD vs Alzeheimer’s

Answer 9

More executive dysfunction and visual-spatial impairment in LBD rather than anterograde memory loss in AD

Also, hallucinations highly suggest LBD

Question 10

PD and LBD can be thought of as. . .

Answer 10

. . . two ends of the same pathological spectrum

They are not necessarily two different diagnoses, per se

Question 11

In PD, Lewy bodies are found predominately in the ___. In LBD, they are also found in the ___.

Answer 11

In PD, Lewy bodies are found predominately in the brainstem. In LBD, they are also found in the limbic and cortical regions.

Question 12

Serology studies to order when considering reversible etiologies of dementia

Answer 12

HIV

Lyme

Syphilis

Question 13

Symptomatic treatment of RBD for patients with Lewy body diseases

Answer 13

Melatonin

Clonazepam

Question 14

Hallmark imaging finding of progressive supranuclear palsy

Answer 14

Atrophy of the midbrain, Hummingbird, and Mickey-mouse signs

Question 15

Hummingbird sign

Answer 15

Radiographic sign of midbrain atrophy in PSP

Shows midbrain atrophy with an intact pons

Question 16

Mickey-mouse sign

Answer 16

Radiographic sign of midbrain atrophy in PSP

Note the widening of the cleft between the crus cerebri

Question 17

Levodopa in LBD

Answer 17

May be effective in managing parkinsonism, but can exacerbate hallucinations in LBD

Should be uptitrated slowly and carefully

Question 18

Three main features of progressive supranuclear palsy + parkinsonism

Answer 18

• Downward gaze palsy
• Behavioral change (apathy, disinhibition, impaired reasoning)
• Postural instability
• + Parkinsonism