24 research outputs found
UWOMJ Volume 34
Schulich School of Medicine & Dentistryhttps://ir.lib.uwo.ca/uwomj/1008/thumbnail.jp
Swayed by sound: sonic guidance as a neurorehabilitation strategy in the cerebellar ataxias
Cerebellar disease leads to problems in controlling movement. The most common
difficulties are dysmetria and instability when standing.
Recent understanding of cerebellar function has expanded to include non -motor
aspects such as emotional, cognitive and sensory processing. Deficits in the
acquisition and processing of sensory information are one explanation for the
movement problems observed in cerebellar ataxia. Sensory deficits result in an
inability to make predictions about future events; a primary function of the
cerebellum. A question therefore, is whether augmenting or replacing sensory
information can improve motor performance in cerebellar disease. This question is
tested in this thesis by augmenting sensory information through the provision of an
auditory movement guide.A variable described in motor control theory (tau) was used to develop auditory
guides that were continuous and dynamic. A reaching experiment using healthy
individuals showed that the timing of peak velocity, audiomotor coordination
accuracy, and velocity of approach, could be altered in line with the movement
parameters embedded in the auditory guides. The thesis then investigated the use of
these sonic guides in a clinical population with cerebellar disease. Performance on
neurorehabilitation exercises for balance control was tested in twenty people with
cerebellar atrophy, with and without auditory guides. Results suggested that
continuous, predictive, dynamic auditory guidance is an effective way of improving
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movement smoothness in ataxia (as measured by jerk). In addition, generating and
swaying with imaginary auditory guides was also found to increase movement
smoothness in cerebellar disease.Following the tests of instantaneous effects, the thesis then investigated the longterm consequences on motor behaviour of following a two -month exercise with
auditory guide programme. Seven people with cerebellar atrophy were assessed pre - and post -intervention using two measures, weight -shifting and walking. The results
of the weight -shifting test indicated that the sonic -guide exercise programme does
not initiate long -term changes in motor behaviour. Whilst there were minor,
improvements in walking, because of the weight -shifting results, these could not be
attributed to the sonic guides. This finding confirms the difficulties of motor
rehabilitation in people with cerebellar disease.This thesis contributes original findings to the field of neurorehabilitation by first
showing that on -going and predictive stimuli are an appropriate tool for improving
motor behaviour. In addition, the thesis is the first of its kind to apply externally
presented guides that convey continuous meaningful information within a clinical
population. Finally, findings show that sensory augmentation using the auditory
domain is an effective way of improving motor coordination in some forms of
cerebellar disease
PRELIMINARY FINDINGS OF A POTENZIATED PIEZOSURGERGICAL DEVICE AT THE RABBIT SKULL
The number of available ultrasonic osteotomes has remarkably increased. In vitro and in vivo studies
have revealed differences between conventional osteotomes, such as rotating or sawing devices, and
ultrasound-supported osteotomes (Piezosurgery®) regarding the micromorphology and roughness
values of osteotomized bone surfaces.
Objective: the present study compares the micro-morphologies and roughness values of
osteotomized bone surfaces after the application of rotating and sawing devices, Piezosurgery
Medical® and Piezosurgery Medical New Generation Powerful Handpiece.
Methods: Fresh, standard-sized bony samples were taken from a rabbit skull using the following
osteotomes: rotating and sawing devices, Piezosurgery Medical® and a Piezosurgery Medical New
Generation Powerful Handpiece. The required duration of time for each osteotomy was recorded.
Micromorphologies and roughness values to characterize the bone surfaces following the different
osteotomy methods were described. The prepared surfaces were examined via light microscopy,
environmental surface electron microscopy (ESEM), transmission electron microscopy (TEM), confocal
laser scanning microscopy (CLSM) and atomic force microscopy. The selective cutting of mineralized
tissues while preserving adjacent soft tissue (dura mater and nervous tissue) was studied. Bone
necrosis of the osteotomy sites and the vitality of the osteocytes near the sectional plane were
investigated, as well as the proportion of apoptosis or cell degeneration.
Results and Conclusions: The potential positive effects on bone healing and reossification
associated with different devices were evaluated and the comparative analysis among the different
devices used was performed, in order to determine the best osteotomes to be employed during
cranio-facial surgery