Ignite Creation Date:
2024-05-05 @ 11:41 AM
Last Modification Date:
2024-10-26 @ 9:11 AM
Study NCT ID:
NCT00106743
Status:
COMPLETED
Last Update Posted:
2019-12-12
First Post:
2005-03-29
Brief Title:
Natural History and Genetic Studies of Usher Syndrome
Sponsor:
National Eye Institute NEI
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
Natural History and Genetic Studies of Usher Syndrome
Status:
COMPLETED
Status Verified Date:
2019-04-30
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
This study will explore clinical and genetic aspects of Usher syndrome an inherited disease causing deafness or impaired hearing visual problems and in some cases unsteadiness or balance problems Patients with type 1 Usher syndrome usually are deaf from birth and have speech and balance problems Patients with type 2 disease generally are hearing impaired but have no balance problems Patients with type 3 disease have progressive hearing loss and balance problems All patients develop retinitis pigmentosa an eye disease that causes poor night vision and eventually blindness
Patients of any age with Usher syndrome may be eligible for this study Patients who have had eye and hearing evaluations are asked to send their medical records to the research team at the National Eye Institute NEI for review They are also asked to have a blood sample drawn by a medical professional and sent to NEI for genetic analysis Finally they are interviewed about their family histories particularly about other relative with eye disease Patients who have not been evaluated previously have the following tests and procedures at NIH
Family medical history especially regarding eye disease A family tree is drawn
Blood draw for genetic studies of Usher syndrome
Eye examination to assess visual acuity and eye pressure and to examine pupils lens retina and eye movements
Electroretinogram ERG to test the function of visual cells Wearing eye patches the patient sits in a dark room for 30 minutes Electrodes are taped to the forehead and the eye patches are removed The surface of the eye is numbed with eye drops and contact lenses are placed on the eyes The patient looks inside a hollow dark globe and sees a series of light flashes Then a light is turned on inside the globe and more flashes appear The contact lenses sense small electrical signals generated by the retina when the light flashes
Fluorescein angiography to evaluate the eyes blood vessels A yellow dye is injected into an arm vein and travels to the blood vessels in the eyes Pictures of the retina are taken using a camera that flashes a blue light into the eye The pictures show if any dye has leaked from the vessels into the retina indicating possible blood vessel abnormality
Hearing tests to help determine the patients type of Usher syndrome Tests to evaluate hearing include examination of both ears with an otoscope evaluation of the middle ear and inner ear and hearing tests using earphones that deliver tones and words the subject listens and responds to
Vestibular testing for balance function Balance testing involves three procedures
Videonystagmography This test records eye movements with little cameras First the patient follows the movements of some small lights Next while wearing goggles the patient lies on an exam table and turns to the right and left Lastly a soft stream of air is blown into the patients ears four times once in each ear with cool air and once in each ear with warm air
Rotary chair test With electrodes placed on the forehead the patient sits in a rotary chair in a dark room Several red lights appear on the wall of the room and the patient follows the lights as they move back and forth Then the chair turns at several speeds all slower than a merry-go-round
Vestibular evoked potential Electrodes are placed behind the patients ear and at the base of the neck Seated in a reclining chair and wearing earphones the patient hears a brief series of loud clicking sounds When the sounds are on the patient is asked to lift his or her head up a few inches from the chair The electrodes record information from the muscles in the neck as the sounds enter the ear
Patients of any age with Usher syndrome may be eligible for this study Patients who have had eye and hearing evaluations are asked to send their medical records to the research team at the National Eye Institute NEI for review They are also asked to have a blood sample drawn by a medical professional and sent to NEI for genetic analysis Finally they are interviewed about their family histories particularly about other relative with eye disease Patients who have not been evaluated previously have the following tests and procedures at NIH
Family medical history especially regarding eye disease A family tree is drawn
Blood draw for genetic studies of Usher syndrome
Eye examination to assess visual acuity and eye pressure and to examine pupils lens retina and eye movements
Electroretinogram ERG to test the function of visual cells Wearing eye patches the patient sits in a dark room for 30 minutes Electrodes are taped to the forehead and the eye patches are removed The surface of the eye is numbed with eye drops and contact lenses are placed on the eyes The patient looks inside a hollow dark globe and sees a series of light flashes Then a light is turned on inside the globe and more flashes appear The contact lenses sense small electrical signals generated by the retina when the light flashes
Fluorescein angiography to evaluate the eyes blood vessels A yellow dye is injected into an arm vein and travels to the blood vessels in the eyes Pictures of the retina are taken using a camera that flashes a blue light into the eye The pictures show if any dye has leaked from the vessels into the retina indicating possible blood vessel abnormality
Hearing tests to help determine the patients type of Usher syndrome Tests to evaluate hearing include examination of both ears with an otoscope evaluation of the middle ear and inner ear and hearing tests using earphones that deliver tones and words the subject listens and responds to
Vestibular testing for balance function Balance testing involves three procedures
Videonystagmography This test records eye movements with little cameras First the patient follows the movements of some small lights Next while wearing goggles the patient lies on an exam table and turns to the right and left Lastly a soft stream of air is blown into the patients ears four times once in each ear with cool air and once in each ear with warm air
Rotary chair test With electrodes placed on the forehead the patient sits in a rotary chair in a dark room Several red lights appear on the wall of the room and the patient follows the lights as they move back and forth Then the chair turns at several speeds all slower than a merry-go-round
Vestibular evoked potential Electrodes are placed behind the patients ear and at the base of the neck Seated in a reclining chair and wearing earphones the patient hears a brief series of loud clicking sounds When the sounds are on the patient is asked to lift his or her head up a few inches from the chair The electrodes record information from the muscles in the neck as the sounds enter the ear
Detailed Description:
Background and objectives
The Usher syndromes are a group of clinically variable and genetically heterogeneous autosomal recessive syndromes On the basis of clinical findings at least three types exist Patients with Usher type I are born deaf have vestibular problems and are thought to perceive night blindness in early childhood Patients with Usher type II are born with a hearing deficit but are able to develop intelligible speech do not have balance problems night vision problems and visual field changes are noted later Patients with Usher type III are born with relatively good hearing that deteriorates over a decade or more they can have progressive balance problems and they report night blindness in childhood or teens Seven genes have been mapped so far for Usher type I while five of these genes have been identified For Usher type II four genes have been mapped and three of these have been identified while there is one cloned gene for Usher type III Quite a lot of information is still unknown regarding the genetic nature of this syndrome The picture of the three clinical types of Usher syndrome has also not been well studied up to this point and cross sectional studies seems to be the only source of the information available so far regarding the natural history of the disease The aim of this protocol is to better study the natural history of the disease and also make specific genotype-phenotype correlations
Study population
A total of 200 participants including patients affected with all three clinical types of Usher syndrome and up to 200 unaffected relatives will be enrolled to the protocol Unaffected family members primarily parents and siblings will be enrolled to provide a blood sample when considered helpful for linkage analysis Family members will be considered unaffected if they have had a previous normal examination and they don t have any symptoms of decreased night or peripheral vision
Methods
Participants will undergo ophthalmologic audiologic and vestibular evaluation in order to be clinically characterized Blood will be obtained by all participating subjects for the molecular studies Patients who cannot come to NIH or a collaborating Institution for participation will be asked to provide a blood sample for genotyping and a copy of their ophthalmologic audiology and vestibular records to classify phenotype Each off-site participant will be consented over the phone by an NEI investigator All participants will be requested to fill out a questionnaire
Outcome measures
Affected participants will be phenotypically categorized in one of the three clinical types based on audiology and vestibular findings
The Usher syndromes are a group of clinically variable and genetically heterogeneous autosomal recessive syndromes On the basis of clinical findings at least three types exist Patients with Usher type I are born deaf have vestibular problems and are thought to perceive night blindness in early childhood Patients with Usher type II are born with a hearing deficit but are able to develop intelligible speech do not have balance problems night vision problems and visual field changes are noted later Patients with Usher type III are born with relatively good hearing that deteriorates over a decade or more they can have progressive balance problems and they report night blindness in childhood or teens Seven genes have been mapped so far for Usher type I while five of these genes have been identified For Usher type II four genes have been mapped and three of these have been identified while there is one cloned gene for Usher type III Quite a lot of information is still unknown regarding the genetic nature of this syndrome The picture of the three clinical types of Usher syndrome has also not been well studied up to this point and cross sectional studies seems to be the only source of the information available so far regarding the natural history of the disease The aim of this protocol is to better study the natural history of the disease and also make specific genotype-phenotype correlations
Study population
A total of 200 participants including patients affected with all three clinical types of Usher syndrome and up to 200 unaffected relatives will be enrolled to the protocol Unaffected family members primarily parents and siblings will be enrolled to provide a blood sample when considered helpful for linkage analysis Family members will be considered unaffected if they have had a previous normal examination and they don t have any symptoms of decreased night or peripheral vision
Methods
Participants will undergo ophthalmologic audiologic and vestibular evaluation in order to be clinically characterized Blood will be obtained by all participating subjects for the molecular studies Patients who cannot come to NIH or a collaborating Institution for participation will be asked to provide a blood sample for genotyping and a copy of their ophthalmologic audiology and vestibular records to classify phenotype Each off-site participant will be consented over the phone by an NEI investigator All participants will be requested to fill out a questionnaire
Outcome measures
Affected participants will be phenotypically categorized in one of the three clinical types based on audiology and vestibular findings
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 05-EI-0096 | None | None | None |