title: Computerized spiral analysis using the iPad.
abstract: Digital analysis of writing and drawing has become a valuable research and clinical tool for the study of upper limb motor dysfunction in patients with essential tremor, Parkinson's disease, dystonia, and related disorders. We developed a validated method of computerized spiral analysis of hand-drawn Archimedean spirals that provides insight into movement dynamics beyond subjective visual assessment using a Wacom graphics tablet. While the Wacom tablet method provides robust data, more widely available mobile technology platforms exist.
  
  
  
  We introduce a novel adaptation of the Wacom-based method for the collection of hand-drawn kinematic data using an Apple iPad. This iPad-based system is stand-alone, easy-to-use, can capture drawing data with either a finger or capacitive stylus, is precise, and potentially ubiquitous.
  
  
  
  The iPad-based system acquires position and time data that is fully compatible with our original spiral analysis program. All of the important indices including degree of severity, speed, presence of tremor, tremor amplitude, tremor frequency, variability of pressure, and tightness are calculated from the digital spiral data, which the application is able to transmit.
  
  
  
  While the iPad method is limited by current touch screen technology, it does collect data with acceptable congruence compared to the current Wacom-based method while providing the advantages of accessibility and ease of use.
  
  
  
  The iPad is capable of capturing precise digital spiral data for analysis of motor dysfunction while also providing a convenient, easy-to-use modality in clinics and potentially at home.
authors.affiliation: Columbia University College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Sisti
authors.affiliation: Columbia University College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Brandon
authors.initials: B
authors.lastname: Christophe
authors.affiliation: Department of Computer Science, Columbia College, USA.
authors.forename: Audrey Rakovich
authors.initials: AR
authors.lastname: Seville
authors.affiliation: Columbia University College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Andrew L A
authors.initials: AL
authors.lastname: Garton
authors.affiliation: Columbia University College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Vivek P
authors.initials: VP
authors.lastname: Gupta
authors.affiliation: Columbia University College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Bandin
authors.affiliation: Department of Neurology, Clinical Motor Physiology Laboratory, Columbia University Medical Center, New York, NY, USA.
authors.forename: Qiping
authors.initials: Q
authors.lastname: Yu
authors.affiliation: Department of Neurology, Clinical Motor Physiology Laboratory, Columbia University Medical Center, New York, NY, USA. Electronic address: sp31@cumc.columbia.edu.
authors.forename: Seth L
authors.initials: SL
authors.lastname: Pullman
mesh_terms: D000368:Aged; D001696:Biomechanical Phenomena; D034201:Computers, Handheld; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*; D006225:Hand / Q000502:physiology / Q000503:physiopathology; D006801:Humans; D016014:Linear Models; D008875:Middle Aged; D063731:Mobile Applications; D009048:Motor Skills; D009069:Movement Disorders / Q000175:diagnosis* / Q000503:physiopathology; D011312:Pressure; D012720:Severity of Illness Index; D014202:Tremor / Q000175:diagnosis / Q000503:physiopathology; D014584:User-Computer Interface
keywords: Computerized spiral analysis; Graphonomics; Movement disorders; Telemedicine; iPad