The Effect of Low-Level Laser Stimulation on Hearing Thresholds

• ClinicalTrials.gov Identifier: NCT01820416
• Recruitment Status: Terminated
• First Posted: March 28, 2013
• Results First Posted: June 1, 2017
• Last Update Posted: June 1, 2017
• Sponsor: University of Iowa
• Collaborator: GN Resound
• Information provided by (Responsible Party): Shawn Goodman, University of Iowa

Tracking Information

• First Submitted Date: March 25, 2013
• First Posted Date: March 28, 2013
• Results First Submitted Date: March 1, 2017
• Results First Posted Date: June 1, 2017
• Last Update Posted Date: June 1, 2017
• Study Start Date: September 2009
• Actual Primary Completion Date: December 2009 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: April 26, 2017)

Change in Speech Perception [ Time Frame: 7-10 days after baseline measures recorded ]

Hearing status, as assessed by the Connected Sentence Test (CST). Difference scores (post-test - pretest) are reported. The CST approximates everyday conversation. Scoring is based on the number of correctly repeated key words. Higher numbers indicate better scores. The minimum score is 0 (0%) and the maximum is 100 (100%). When comparing test-retest scores for an individual, Cox et al. (1988) suggest that changes of 15% or more (based on 100 key words) are indicative of significant changes. We subtracted the post-test from the pre-test, so that negative difference scores indicate worse performance, and positive difference scores indicate better performance. Difference scores with an absolute value smaller than 15 are interpreted as no significant change. In addition, pre- and post-test performance was assessed for groups using t-tests on the difference scores.

Original Primary Outcome Measures (submitted: March 25, 2013)

Change in Hearing Status [ Time Frame: one week later after baseline ]

Hearing status assessed by test battery: standard hearing test (audiogram), tympanograms, otoacoustic emissions, speech perception.

• Current Secondary Outcome Measures: Not Provided
• Original Secondary Outcome Measures: Not Provided
• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: The Effect of Low-Level Laser Stimulation on Hearing Thresholds
• Official Title: The Effect of Low-Level Laser Stimulation on Hearing Thresholds
• Brief Summary: The purpose of this study is to determine whether low-level laser therapy can improve hearing thresholds in individuals with hearing loss. Subjects will be randomly assigned to a treatment, placebo, or control group. The treatment group will be given a three treatment of low-level laser therapy, which consists of shining low-level lasers beams onto the ear and head. The laser beams are cool to the touch, and do not cause discomfort. Each laser treatment will last approximately 4 minutes. Three treatments will be applied three times within the course of one week. Hearing tests will be administered immediately before treatment, immediately after treatment, and six weeks after treatment. Results will be analyzed to determine the effect of the laser treatment on hearing.
• Detailed Description: Low-level laser therapy has been practiced for about 20 years in Europe and is beginning to be practiced in the US. Theoretically, laser energy in the red and near infrared light spectrum is capable of penetrating 2-5 cm into tissue and can stimulate mitochondria in the cells to produce more energy (through the production of adenosine triphosphate), which in turn may help prevent or repair tissue damage. The effects of low-level laser therapy on hearing have not been well studied. It has been suggested that laser therapy might help repair damage to the cochlea and restore some degree of hearing loss. Studies of low-level laser stimulation of cochleae utilizing microscopy, PET imaging, and MRI suggest potential therapeutic benefit to hearing. While preliminary studies suggest a possible improvement in hearing thresholds, a carefully controlled study is needed to verify the results using a valid battery of audiological tests.
• Study Type: Interventional
• Study Phase: Not Applicable
• Study Design: Allocation: Randomized; Intervention Model: Parallel Assignment; Masking: Triple (Participant, Investigator, Outcomes Assessor); Primary Purpose: Treatment
• Condition: Hearing Loss

Intervention

• Radiation: Low-level Laser Therapy
  Portable unit containing two laser diodes producing 532 and 635 nm wavelengths. Both diodes produced energy levels of 7.5 mw (class IIIb). Beams from both diodes were dispersed through lenses to create parallel line-generated beams, rather than spots. The 532 nm light was constant, and the 635 nm light was pulsed, with frequencies of 15 and 33 Hz. The pulsing alternated between frequencies every 30 seconds.
  Other Name: Erchonia EHL laser (Erchonia Medical, Inc.)
• Other: Placebo Comparator: Disabled Laser
  Portable unit containing two DISABLED laser diodes. Same protocol was followed as for the Experimental (radiation) group, except that the disabled diodes produced no radiation.

Study Arms

• Experimental: Low-Level Laser Therapy
  Low-level laser applied for approximately 4 minutes to the area around the pinna, the back of the neck, and the top of the head.
  Intervention: Radiation: Low-level Laser Therapy
• Placebo Comparator: Disabled Laser
  Low-level laser device with laser diodes disabled. Also applied for approximately 4 minutes to the area around the pinna, the back of the neck, and the top of the head.
  Intervention: Other: Placebo Comparator: Disabled Laser
• No Intervention: Control
  Visit laboratory using same schedule as experiment and placebo. No Low-level laser or any treatment applied. Used to assess normal test-retest variability.

• Publications *: Goodman SS, Bentler RA, Dittberner A, Mertes IB. The effect of low-level laser therapy on hearing. ISRN Otolaryngol. 2013 Apr 23;2013:916370. doi: 10.1155/2013/916370. eCollection 2013.

Recruitment Information

• Recruitment Status: Terminated
• Actual Enrollment (submitted: March 25, 2013): 35
• Original Actual Enrollment: Same as current
• Actual Study Completion Date: December 2009
• Actual Primary Completion Date: December 2009 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• bilateral sensorineural hearing loss
• normal middle ear status

Exclusion Criteria:

• pregnant or lactating
• serious mental health illness or medical/psychiatric hospitalization
• treatment with cancer chemotherapeutic agents or aminoglycoside antibiotics
• taking Aspirin, Ibuprofen, Naprosyn, Aleve
• taking any Quinine-related drugs
• taking any loop diuretics
• have a developmental disability or cognitive impairment
• history of drug abuse
• involved in litigation or claim related to hearing loss
• regularly exposed to significant occupational or recreational noise
• have a photosensitivity disorder
• have a retinal disease

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years to 75 Years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: United States

Administrative Information

• NCT Number: NCT01820416
• Other Study ID Numbers: 200808718
• Has Data Monitoring Committee: No
• U.S. FDA-regulated Product: Not Provided
• IPD Sharing Statement: Not Provided
• Current Responsible Party: Shawn Goodman, University of Iowa
• Original Responsible Party: Same as current
• Current Study Sponsor: University of Iowa
• Original Study Sponsor: Same as current
• Collaborators: GN Resound

Investigators

• Principal Investigator: Shawn S Goodman, PhD; University of Iowa

• PRS Account: University of Iowa
• Verification Date: April 2017