Sean Rogers

Nilotinib Effects in Parkinson’s disease and Dementia with Lewy bodies

Background: We evaluated the effects of low doses of the tyrosine kinase Abelson (Abl) inhibitor Nilotinib, on safety and pharmacokinetics in Parkinson’s disease dementia or dementia with Lewy bodies. Objectives: The primary outcomes of this study were safety and tolerability; pharmacokinetics and target engagement were secondary, while clinical outcomes were exploratory. Methods: Twelve subjects were randomized into 150 mg (n = 5) or 300 mg (n = 7) groups and received Nilotinib orally every day for 24 weeks. Results: This study shows that 150 mg and 300 mg doses of Nilotinib appear to be safe and tolerated in subjects with advanced Parkinson’s disease. Nilotinib is detectable in the cerebrospinal fluid (CSF) and seems to engage the target Abl. Motor and cognitive outcomes suggest a possible beneficial effect on clinical outcomes. The CSF levels of homovanillic acid are significantly increased between baseline and 24 weeks of treatment. Exploratory CSF biomarkers were measured. Conclusions: This small proof-of-concept study lacks a placebo group and participants were not homogenous, resulting in baseline differences between and within groups. This limits the interpretations of the biomarker and clinical data, and any conclusions should be drawn cautiously. Nonetheless, the collective observations suggest that it is warranted to evaluate the safety and efficacy of Nilotinib in larger randomized, double-blind, placebo-controlled trials.

Using Directional Deep Brain Stimulation to Co-activate the Subthalamic Nucleus and Zona Incerta for Overlapping Essential Tremor/Parkinson's Disease Symptoms

This index case report describes a novel programming approach that utilizes the 8-contact directional Deep Brain Stimulation (DBS) lead to effectively control the akinesia, rigidity and tremor of Parkinsons Disease (PD), as well as a severe kinetic tremor of Essential Tremor (ET), in a patient with overlapping symptoms of both PD and ET. Through utilizing a bipolar directional montage on a single segmented contact, symptom control was attained via likely co-activation of the Subthalamic Nucleus (STN) and the adjacent Zona Incerta (ZI). The patient is a 67-year-old professional guitarist with a long-standing diagnosis of ET manifesting with bilateral kinetic tremor, who then developed right lateralizing symptoms indicative of PD. After optimal medical management did not confer sufficient control, he underwent left-sided unilateral DBS targeting the STN. Both intraoperatively and post-operatively, omnidirectional, and directional electrode review resulted in significant akinesia, rigidity, and as well as resting tremor control but failed to sufficiently improve the kinetic tremor. As electrode 2B was shown to be the most efficacious with the largest therapeutic window, a bipolar directional montage on a single segmented contact was tried with the idea of possibly further extending the axial asymmetry of the directional stimulation toward the adjacent ZI to impact the kinetic tremor. This montage resulted in full kinetic and resting tremor control as well as akinesia and rigidity response [2B cathode (–), 2A anode (+), 2C anode (+) (1.4 mA, rate 160 Hz, pulse width 60 μs)]. At 6 months post initial programming, no montage changes have been made, and the patient has experienced a reduction in Motor UPDRS scores from 23 to 3 (evaluated off medication), full resolution of kinetic tremor and normalization of handwriting, as well as significant reduction in his medication requirements. This patients response to a single segment bipolar directional montage, and lack of response from monopolar directional stimulation in the same area, does suggest the possibility of further axial asymmetric tissue activation and thus co-activation of both the dorsal STN and adjacent ZI. Further modeling and study are warranted.

Presurgical Rehearsals for Patients Considering “Awake” Deep Brain Stimulation

Simulated surgical environments are rapidly gaining adoption in training students, residents, and members of specialized surgical teams. However, minimal attention has been given to the use of simulated surgical environments to educate patients on surgical processes, particularly procedures that require the active participation of the patient. “Awake” neurosurgery provides a unique situation in which patients openly participate in their operation. We describe a case report, in which a 62-year-old male was referred for “awake” deep brain stimulation implantation, in relation to medically refractory Parkinson’s disease. The patient had significant concerns regarding anxiety and claustrophobia, and toleration of the “awake” procedure. Consequently, we designed a simulated OR environment and process, to recreate the physical experience of the procedure, with minimal cost or risk. This experience was crucial in determining the care plan, as after this experience, the patient opted for an “asleep” alternative. Thus, in certain settings, presurgical rehearsals may have a dramatic impact in the overall course of care.