CleveMed Blogs

Parkinson’s disease is a neurodegenerative disease of the central nervous system and is primarily characterized by cardinal motor symptoms such as tremor, bradykinesia (slowness of movement), and rigidity. Lower extremity symptoms such as gait and balance disturbances (initiating movement, freezing of movement, improper movement form), especially in advanced patients, can be very debilitating, leading to decreased mobility and independence, decreased quality of life, and an increased falling/hip fracture risk ^[1]. A positive PD diagnosis occurs when a minimum of two cardinal symptoms present themselves. However, less attention is given to gait and balance abnormality as it typically develops in the advanced stages of PD.

Standard clinical assessment of gait and balance based on a 0 (no severity) – 4 (high severity) scale is performed using a subset of the Unified Parkinson’s Disease Rating Scale (UPDRS) motor section. Tasks typically consist of foot stomping while seated, gait assessment while walking, arising from chair with arms crossed over the chest, and balance assessment while being pulled backwards. As gait is particularly sensitive to ON-OFF therapy state changes in PD and incorporates upper extremity function such as arm swing as well as rigidity and bradykinesia in lower extremities, gait analysis may be a reliable method of assessing overall motor function over time in PD ^[2].

When diagnosed with PD, the first line of treatment typically consists of L-Dopa medication to alleviate motor symptoms. However over time, drug effectiveness decreases, requiring the patient to increase dosage. Frequent and stronger side effects such as dyskinesias (uncontrolled arm movement) and unpredictable “on”/”off” episodes are cause for more invasive therapeutic intervention. Deep brain stimulation (DBS) has been widely recognized as an appropriate treatment option when medication no longer adequately alleviates motor symptom severity. Several therapy targets have been established for PD. Subthalamic nucleus (STN) and Globus Pallidus Interna (GPi) stimulation are recognized treatments for sustained improvement in tremor, rigidity, and bradykinesia ^{[3, 4]}. However the effects on gait disturbance are less understood. During DBS lead placement and post-evaluation, neurologists adjust several settings: electrode contact configuration and stimulation parameters (frequency, pulse width, and amplitude). Studies show that while high-frequency/high voltage stimulation improves cardinal symptoms, patients exhibit increased frequency of freezing episodes. However, stimulation at lower frequencies has demonstrated improved gait ^[5].

New PD gait therapies are being researched and developed and existing interventions further established. Another DBS target, the pedunculopontine nucleus (PPN), located near the brain stem plays an important role in locomotion function in animal models, specifically initiation and modulation of gait ^[6-8]. Patients with advanced stages of PD only exhibit mild improvement of freezing with standard medication such as L-Dopa ^{[9, 10]}. Preliminary studies of PPN surgeries off-medication marked a significant improvement of the UPDRS motor exam section III, specifically gait and postural qualities. In addition, the combination of STN and PPN DBS resulted in a further significant improvement. Despite promising results, PPN surgical intervention is currently in its infancy as little is known about the nucleus’ function in humans and how well animal model testing translates to human clinical trials ^[7].

CleveMed has announced the promotion of Joseph P. Giuffrida, PhD to Vice President, General Manager of the Division of Movement Disorders. CleveMed is continually expanding as a medical device company and Dr. Giuffrida will continue to fill a crucial role to assist with the company’s success.

Dr. Giuffrida, 33, completed his BS, MS and PhD in Biomedical Engineering at Case Western Reserve University with a concentration in rehabilitation engineering. He began his career at CleveMed in 2000 as an Applications Engineer and upon receipt of his PhD in 2004, became a Principal Investigator and eventually Director of the Division of Movement Disorders. Within these roles, Dr. Giuffrida has secured over $10 million in funding from both the National Institutes of Health and the State of Ohio to fuel the research, development, and commercialization of innovative medical devices focused on aiding in the diagnosis and therapy of movement disorders. He has secured FDA clearance to market for a number of CleveMed systems, managed reimbursement strategies for new and emerging technology, established multiple world renowned key opinion leaders and clinical consultants, and lead the marketing and sales teams for CleveMed’s clinical movement disorder products as well as the research and education product lines.

Most notably, CleveMed’s Division of Movement Disorders commercialized and launched Kinesia under Dr. Giuffrida’s direction. This technology is intended to provide a standardized platform for objectively quantifying motor symptoms associated with Parkinson’s disease. Additional research and development in this Division is focused on extending the market applications for Kinesia from clinical office visits to home monitoring and deep brain stimulation programming, assistive technologies to aid in communication for persons with limited mobility and speech impairment and the development of rehabilitation systems to aid in motor recovery after brain injuries such as stroke or cerebral palsy.

In addition to the Division of Movement Disorders, Dr. Giuffrida also manages CleveMed’s line of products focused on the research and education market. Dr. Giuffrida was able to commercialize CleveMed’s wireless physiological monitoring technology into specific academic and university based target applications to increase CleveMed’s sales both domestically and internationally.

Parkinson’s disease (PD) is a neurodegenerative disorder that is caused by the death of dopamine producing neurons in the brain. Primary motor symptoms of PD include tremor, rigidity, bradykinesia (slowed movements or hesitations) and gait and balance issues. Since there is currently no cure for PD, the symptoms are treated typically with pharmaceutical interventions.

One of the more common medications prescribed for PD is L-Dopa, which is used to increase levels of dopamine in the brain. While effective, a common issue with the use of L-Dopa is that there is a fine line between the correct amount of medication and too much. Too much medication results in dyskinesias, or wild, uncontrollable movements. Also, the effectiveness of L-Dopa decreases over time.

When L-Dopa is no longer effective as a treatment for PD symptoms, patients can consider a surgical procedure called deep brain stimulation, or DBS. When patients opt to have DBS surgery, tiny electrodes are implanted in the brain through a hole in the skull which emit pulses of stimulation that aide in symptom alleviation. The location of the electrode can vary depending on the patient but the two most common are subthalamic nucleus (STN) and the globus pallidus interna (GPi). A patient can also have electrodes implanted on one side of the brain or both, depending on whether their symptoms are unilateral or bilateral. The electrode or electrodes connect to a pulse generator which is typically implanted below the skin near the collarbone. The implanted pulse generator, or IPG, controls the electrode stimulation output. Parameters such as amplitude (the power of the stimulation), frequency (how often the stimulations pulses occur) and duration (how long each pulse lasts) must be set.

During DBS surgery the patient is awake and fully aware. This is because a nurse must perform motor assessments with the patient to determine if the electrode has been placed in an optimum location and depth. This assessment includes motor tasks that the patient is asked to complete to determine the severity levels of their symptoms. This can sometimes be time consuming as the patient must complete the assessment each time the electrode is moved.

Once surgery is completed, patients will return to the clinic to have the IPG settings adjusted. Again, a nurse will administer a motor assessment and alter the amplitude, frequency and duration of the pulses until an optimum combination is found with best alleviates the patient’s symptoms. This adjustment is repeated a number of times as symptoms worsen due to the progression of the disease.

While the exact reason DBS works is still not known, the number of PD patient lives the surgery has improved is dramatic. Patients with debilitating motor symptoms that leave them nearly incapable of performing activities of daily living can have the ability to move and function as they did before their diagnosis of PD. This is not to say that DBS does not have risks. It is a major surgical operation and results are not the same for each patient. The first step to determining whether or not DBS would be appropriate for any PD patient would be to discuss their options with a certified movement disorder clinician or neurologist.