Evaluation of a Tongue Operated Assistive Technology for Individuals With Severe Paralysis
Condition: Quadriplegia; Spinal Cord Injury; ALS
MeSH terms: Spinal Cord Injuries; Quadriplegia
Study type: Interventional
Phase: Phase 1

Summary: 
      This study was intended to evaluate a new assistive neuro-technology, known as the Tongue
      Drive System (TDS), by its potential end-users, i.e. individuals with severe disabilities,
      who are the best experts for indicating the benefits and possible shortcomings of any new
      ANT. Our goal is to assess the acceptability and usability of the TDS for various tasks that
      are important in daily lives of these individuals, such as computer access, wheeled mobility,
      and environmental control.
    

Detailed description: 
      A new assistive neuro-technology (ANT), called the Tongue Drive System (TDS), enables
      individuals with severe disability access their environment with nothing but their tongue
      motion. The human tongue is inherently capable of sophisticated control and manipulation
      tasks with many degrees of freedom. It can move rapidly and accurately within the mouth such
      that the tip can touch every single tooth. The direct connection between the brain and the
      tongue generally allows it to escape damage even in severe spinal cord injuries (SCI). Unlike
      the brain, the tongue is accessible, and its location inside the mouth affords a degree of
      privacy.

      TDS consists of a magnetic tracer, the size of a lentil, attached to the tongue by gluing,
      implantation, or piercing. The tracer generates a magnetic field inside and around the mouth
      that is detected by an array of magnetic sensors mounted on a wireless headset.
      Tongue-movement-induced changes in the magnetic field are sent wirelessly to an ultra-mobile
      computer or smartphone, carried by the user, which processes and translates every tongue
      motion to a particular user-defined function.

      Once an individual with disability is "enabled" to access a computing device, he/she can
      nearly do everything that an able-bodied individual can do with that device. This includes
      communicating, education, training, entertainment, and controlling other devices such as
      powered wheelchairs (PWC), assistive robotic manipulators, and other home/office appliances
      on a local area network (LAN). Even the individual's own natural or prosthetic limbs can be
      manipulated to move by functional electrical stimulation (FES).

      This study was intended to evaluate the TDS by the ultimate intended users, individuals with
      severe disabilities, who are the best experts for indicating the benefits and possible
      shortcomings of any new ANT. Our goal is to assess the acceptability and usability of the TDS
      for various tasks that are important in daily life such as computer access, wheeled mobility,
      and environmental control.

      Three groups of subjects were recruited:

      Group-A: Able-bodied subjects who already have tongue piercing

      Group-B: Able-bodied subjects who wanted to receive tongue piercing as part of this trial

      Group-C: Subjects with high-level disability, who wanted to receive tongue piercing as part
      of this trial

      Each group of subjects participated in a battery of tasks that quantitatively measures their
      performance in accessing computers and driving wheelchairs using the TDS.

      We also devised acceptable procedures for receiving a magnetic tongue piercing (required in
      order to use the TDS), and assess its potential safety issues.
    

Intervention name(s): Tongue Piercing; Usability assessment
Intervention type(s): Procedure; Device
Intervention description(s): Subjects brush their teeth, and then swish and spit with chlorhexidine mouthwash for 30-60s. Subjects would be placed in a semirecumbent position in a procedure chair. After marking the piercing site using a sterilized surgical marking pen the protruded tongue would be pierced. Anesthesia may be used during the piercing at the discretion of the operator and the subject. A sterilized titanium or surgical grade stainless steel piercing tongue stud would be placed in an appropriate position on the tongue to minimize complications from the piercing but also facilitate good functionality of the TDS.; Computer access: Subjects wear the TDS and get trained. Then they sit 1.5 m from a 22" LCD monitor. Then they use TDS to conduct several tasks using their tongues, such as clicking on target objects and navigating through on-screen maze, while the computer registers their tongue commands and measures their performance.
Wheelchair control: Subjects wear the TDS and use it to drive an electrically powered wheelchair through an obstacle course using their tongues. The operator measured the time it takes for the subjects to drive through the course as well as the number of collisions.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Supportive Care
Keywords: Disability; Quadriplegia; Paralysis; Assistive technology; Quality of life; Computer access; Wheeled mobility