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Evoked Retinal Response

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ClinicalTrials.gov Identifier: NCT01415453
Recruitment Status : Terminated (Poor enrollment.)
First Posted : August 12, 2011
Results First Posted : April 5, 2013
Last Update Posted : April 5, 2013
Sponsor:
Information provided by (Responsible Party):
Ronald H. Silverman, Columbia University

July 25, 2011
August 12, 2011
June 21, 2012
April 5, 2013
April 5, 2013
July 2011
June 2012   (Final data collection date for primary outcome measure)
Phosphene Perception in Response to Ultrasound Pulse. [ Time Frame: Subjects will undergo a single examination of approximately 15 minute duration during which they will report perception of phosphenes during ultrasound exposure. ]
The investigators will test the hypothesis that compression of retinal nerves by ultrasound force will cause perception of light (phosphenes) in blind subjects lacking functioning photoreceptors (retinitis pigmentosa). With each of two 5 msec ARFI exposures, if the subject either perceived the spark of light (phosphene), then it was documented as a positive response; if they did not, it was marked as a negative response.
Phosphene Perception in Response to Ultrasound Pulse. [ Time Frame: Subjects will undergo a single examination of approximately 15 minute duration during which they will report perception of phosphenes during ultrasound exposure. ]
The investigators will test the hypothesis that compression of retinal nerves by ultrasound force will cause perception of light (phosphenes) in blind subjects lacking functioning photoreceptors (retinitis pigmentosa).
Complete list of historical versions of study NCT01415453 on ClinicalTrials.gov Archive Site
Not Provided
Not Provided
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Evoked Retinal Response
Evoked Visual Response Using Pulsed Ultrasound
Retinitis pigmentosa (RP) is the name given to a group of inherited eye diseases that affect the retina (the light-sensitive part of the eye). RP causes the breakdown of photoreceptor cells (cells in the retina that detect light). Photoreceptor cells capture and process light helping us to see. As these cells breakdown and die, people experience progressive vision loss. There is no known cure for retinitis pigmentosa. The investigators have observed that short pulses of focused ultrasound can cause perception of light when directed to spots on the retinal surface. The investigators propose to conduct a study to determine if pulsed ultrasound will stimulate the perception of light in the absence of functional photoreceptors in people with RP
Patients affected by retinitis pigmentosa (RP) and related diseases suffer loss of vision due to death of photoreceptor cells. The investigators have observed that short pulses of focused ultrasound can cause perception of light (phosphenes) when directed to spots on the retinal surface. If this phenomenon is caused by direct stimulation of the retinal nerves, which seems probable, then it might be possible to use this phenomenon to produce a form of vision in such patients. The investigators propose to conduct a study of a small cohort of patients affected by RP to determine if pulsed ultrasound will evoke a perception of light in the absence of functional photoreceptors.
Interventional
Not Applicable
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Retinitis Pigmentosa
Procedure: Ultrasound Stimulus
Short pulses of focused ultrasound will be directed at spots on the retinal surface.
Other Name: pulsed ultrasound
Experimental: Retinitis Pigmentosa
Subject will have retinitis pigmentosa and will be legally blind in one or both eyes
Intervention: Procedure: Ultrasound Stimulus
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Terminated
1
10
June 2012
June 2012   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • retinitis pigmentosa
  • legally blind in at least one eye

Exclusion Criteria:

  • unable to lay down on an exam table
Sexes Eligible for Study: All
18 Years to 60 Years   (Adult)
No
Contact information is only displayed when the study is recruiting subjects
United States
 
 
NCT01415453
AAAI1650
No
Not Provided
Not Provided
Ronald H. Silverman, Columbia University
Columbia University
Not Provided
Principal Investigator: Ronald H Silverman, PhD Columbia University
Columbia University
March 2013

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP