Introduction:
Dementia with Lewy Bodies (DLB) is the second most prevalent form of
dementia in older adults, behind Alzheimer’s dementia.(1) The presence
of parkinsonism, visual hallucinations, cognitive fluctuations, and
Rapid Eye Movement (REM) sleep disturbances hallmarks dementia with Lewy
bodies (DLB). (2) The Associated visual hallucinations and illusions
exhibit a high level of complexity, are well-developed, and last over
time.
The room tilt illusion (RTI) or Tortopsia often occurs in individuals
with vestibular system disorders, resulting in a misalignment of visual
representations in the brain. (3). In the extreme form, there is a
complete 180º rotation of the environment, known as the ”upside-down”
illusion.(3) The ”clock drawing test” may be used to determine the
existence of Tortopsia.(4) Visuospatial dysfunction due to
occipitotemporal hypoperfusion may contribute to a room tilt illusion
and palinopsia in patients with DLB.(5) We also propose that early
aggregation of Alpha Synucleins in the vestibular nucleus of the
brainstem may explain the vestibular-visual mismatch and associated
illusions along with early recurrent falls in the early phase of DLB.(6)
To our knowledge, this is the first report on room tilt illusion in DLB.