Help guide our efforts to modernize
Send us your comments by March 14, 2020. Menu

A Trial of Patients With a Charles Bonnet Syndrome (CBS)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT03148249
Recruitment Status : Completed
First Posted : May 10, 2017
Last Update Posted : June 27, 2017
Information provided by (Responsible Party):
Prim. Prof. Dr. Oliver Findl, MBA, Vienna Institute for Research in Ocular Surgery

Brief Summary:
Charles Bonnet Syndrome (CBS) is defined by the occurence of visual hallucinations (VH) in the absence of any mental disorder. Elderly patients with reduced visual acuity due to ophthalmic diseases are most affected. Conditions are often associated with the syndrome of age-related macular degeneration, cataract or glaucoma. Existing data on the syndrome's prevalence in Europe reveal diverse results. Aim of this study was to assess the prevalence of CBS in patients with low visual acuity and to evaluate, if an additional therapeutic interview with and treatment by a psychiatrist is beneficial.

Condition or disease Intervention/treatment Phase
Prevalence, Psychiatrist Intervention Other: interview Not Applicable

Detailed Description:
Patients with a visual acuity of 0.5 LogMAR or less in the better eye were screened for CBS. Instruments used were an interview asking for details of the hallucinations, a mental test and a scale concerning quality of life. Patients with CBS were randomized by minimization in two groups: in group 1, a patient-doctor interview by an ophthalmologist was performed and in group 2 an interview and if needed, a therapy by a psychiatrist. At the 3-months follow up, the psychological strain of patients was recorded again.

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 34 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: A Randomized Control Trial of Patients With a Charles Bonnet Syndrome
Actual Study Start Date : October 10, 2014
Actual Primary Completion Date : February 17, 2016
Actual Study Completion Date : February 1, 2017

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: interview with an ophthalmologist
Patients get an interview with an ophthalmologist
Other: interview
control group: interview, study group: explanation and exploration

Experimental: interview/treatment by a psychiatrist
patients get an interview and a possible treatment by a psychiatrist
Other: interview
control group: interview, study group: explanation and exploration

Primary Outcome Measures :
  1. Quality of life score between the two groups [ Time Frame: 3 months ]
    Quality of life score between the study and control group

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   55 Years to 105 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • written informed consent
  • visual acuity of 0.5 LogMAR or less at both eyes
  • 55 years or older

Patients with CBS:

  • have no mental pathologies such as dementia, psychosis or any other neurological diseases
  • have a normal cognitive state
  • are not able to control the VH
  • know that the VH are not real
  • are usually older
  • have significantly reduced visual acuity due to an bilateral eye pathology

VH associated with CBS:

  • disappear when the eyes are closed
  • are repetitive
  • are complex (eg. objects, geometrical patterns, faces, shapes, figures, scenes, animals or plants)

Exclusion Criteria:

  • dopamine agonist medication
  • temporal lobe epilepsy
  • moderate to severe Alzheimer's dementia
  • present chronic alcohol-/drug abuse
  • bad cognitive state

There are no:

  • auditory or olfactory hallucinations
  • other abnormalities like delusions

Layout table for additonal information
Responsible Party: Prim. Prof. Dr. Oliver Findl, MBA, Univ. Prof. Dr., MBA, Vienna Institute for Research in Ocular Surgery Identifier: NCT03148249    
Other Study ID Numbers: VIROS
First Posted: May 10, 2017    Key Record Dates
Last Update Posted: June 27, 2017
Last Verified: June 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Prim. Prof. Dr. Oliver Findl, MBA, Vienna Institute for Research in Ocular Surgery:
Randomized control trial
Charles Bonnet syndrome
visual hallucinations
age related macular degeneration
patient education
Additional relevant MeSH terms:
Layout table for MeSH terms
Charles Bonnet Syndrome
Perceptual Disorders
Neurobehavioral Manifestations
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms