Development and Pilot Testing of the Tremor Retrainer Smartphone Application for the Treatment of Functional Tremor

Background

Functional tremor is a common and disabling condition with limited treatment options. A prior proof-of-concept pilot study sought to translate entrainment, a key diagnostic feature of functional tremor, into a treatment strategy.

Methods

The Tremor Retrainer smartphone application was developed though a collaboration between neurologists and a software engineer. It analyzes data from smartphone accelerometers to measure baseline tremor frequency, then provides auditory cues at a lower frequency for the patient to match with flexion-extension movements at the wrist. The application provides continuous biofeedback on performance via a visual gauge. Patients with functional tremor underwent a one-week treatment protocol with the Tremor Retrainer application and provided feedback on usability and acceptability to guide software programming.

Results

Three pediatric patients completed the one-week protocol and their feedback was used to modify the software. All patients felt that the application was easy to use and could be effective in treating functional tremor.

Discussion

The Tremor Retrainer smartphone application uses auditory cues and a visual gauge to provide a personalized and widely accessible entrainment-based intervention. Pilot testing in pediatric patients provided key feedback for application design.

Highlights

The Tremor Retrainer smartphone application modulates functional tremor frequency by providing pulsed auditory cues for a patient to match with wrist flexion-extension movements while receiving continuous biofeedback via a visual gauge. This adaption of the diagnostic sign of entrainment has potential as an accessible treatment for patients with functional tremor.

Deep Brain Stimulation for Pediatric Dystonia: A Review of the Literature and Suggested Programming Algorithm

Deep brain stimulation (DBS) is an established intervention for use in pediatric movement disorders, especially dystonia. Although multiple publications have provided guidelines for deep brain stimulation patient selection and programming in adults, there are no evidence-based or consensus statements published for pediatrics. The result is lack of standardized care and underutilization of this effective treatment. To this end, we assembled a focus group of 13 pediatric movement disorder specialists and 1 neurosurgeon experienced in pediatric deep brain stimulation to review recent literature and current practices and propose a standardized approach to candidate selection, implantation target site selection, and programming algorithms. For pediatric dystonia, we provide algorithms for (1) programming for initial session and follow-up sessions, and (2) troubleshooting side effects encountered during programming. We discuss common side effects, how they present, and recommendations for management. This topical review serves as a resource for movement disorders specialists interested in using deep brain stimulation for pediatric dystonia.

Implementation of the Mini-Child Tourette Syndrome Impairment Scale: Relationships to Symptom Severity and Treatment Decisions

Functional impairment is an important factor in Tic Disorder treatment decisions. We evaluated the mini Child Tourette Syndrome Impairment Scale (mini-CTIM) for correlation with symptom severity and association with interventions. A total of 61 randomly selected tic encounters were retrospectively analyzed for mini-CTIM correlation with symptom severity scores and compared between patients who received treatment and those who did not. Regression models identified factors associated with treatment decisions. Mini-CTIM-tic scores correlated with tic severity and mini-CTIM-non-tic scores correlated with attention-deficit hyperactivity disorder (ADHD) severity. Tic treatment was associated with higher child, but not parent, mini-CTIM-tic scores. Regression models identified that comorbidity treatment was predicted by ADHD severity, obsessive compulsive disorder severity, and parent but not child mini-CTIM-non-tic scores. These findings suggest children have valuable insight into their tic-related impairment, but parent assessment is important for evaluating comorbidity-related impairment. The mini-CTIM may be a useful clinical tool for assessing tic-related impairment.

Parent and Patient Perceptions of Functional Impairment Due to Tourette Syndrome: Development of a Shortened Version of the Child Tourette Syndrome Impairment Scale

The Child Tourette Syndrome Impairment Scale (CTIM) rates 37 problems in school, social, and home domains separately for tics and for comorbid diagnoses. However, a shorter version would be easier to implement in busy clinics. Using published data from 85 children with Tourette syndrome, 92 controls, and parents, factor analysis was used to generate a "mini-CTIM" composed of 12 items applied to tic and comorbid diagnoses. Child- and parent-rated mini-CTIM scores were compared and correlated across raters and accounting for clinician-rated tic severity and presence of attention-deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). The mini-CTIM achieved domain Cronbach alphas ranging from 0.71 to 0.94 and intra-item correlation coefficients ranging from 0.84 to 0.96. The resulting scale correlated with clinician-rated tic severity and reflected the presence of ADHD and OCD. The mini-CTIM appears promising as a practical assessment tool for tic- and non-tic-related impairment in children with Tourette syndrome.