Ignite Creation Date:
2024-05-05 @ 10:17 AM
Last Modification Date:
2024-10-26 @ 9:01 AM
Study NCT ID:
NCT00000123
Status:
COMPLETED
Last Update Posted:
2009-09-17
First Post:
1999-09-23
Brief Title:
The Berkeley Orthokeratology Study
Sponsor:
National Eye Institute NEI
Organization:
National Eye Institute NEI
Study Overview
Official Title:
None
Status:
COMPLETED
Status Verified Date:
2009-09
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:
To evaluate the relative efficacy of orthokeratology primarily by assessment of changes in central corneal thickness astigmatism visual acuity endothelial cell density and corneal curvature
To evaluate the relative safety of orthokeratology primarily by assessment of changes in central corneal thickness astigmatism visual acuity endothelial cell density induced corneal edema and epithelial staining
To assess the duration of any orthokeratology treatment effect
To study the mechanisms by which refractive error and visual acuity changes occur in particular the contribution that comes from changes in corneal curvature and shape
To determine whether there were any predisposing ocular factors that could be used to predict which subjects will experience changes or complications
To evaluate the relative safety of orthokeratology primarily by assessment of changes in central corneal thickness astigmatism visual acuity endothelial cell density induced corneal edema and epithelial staining
To assess the duration of any orthokeratology treatment effect
To study the mechanisms by which refractive error and visual acuity changes occur in particular the contribution that comes from changes in corneal curvature and shape
To determine whether there were any predisposing ocular factors that could be used to predict which subjects will experience changes or complications
Detailed Description:
In the early 1960s a group of clinicians asserted that myopia could be reduced and possibly corrected by fitting specially designed contact lenses to induce corneal flattening and thereby reduce the refractive power of the eye This technique known as orthokeratology required that the lenses be fitted and then changed progressively until vision becomes normal or nearly normal Advocates of orthokeratology claimed that corneal changes could be induced in a predictable fashion were often permanent and occurred without causing any adverse effects to the cornea Data on orthokeratology were generally limited poorly documented and did not address the issues of control or failure
The Berkeley Orthokeratology Study was a single center randomized concurrently controlled masked clinical trial Corneal and visual changes in an orthokeratology treatment group were monitored and compared with those observed in a control group whose members wore contact lenses fitted in a standard clinical manner Visual and ocular characteristics were monitored for 15 years
Eighty subjects were studied-40 in an orthokeratology group and 40 in a control group fitted with conventional hard contact lenses The hard lenses chosen for this study were made of either polymethyl methacrylate PMMA or a PMMA-silicone combination Polycon All subjects were initially fitted with PMMA lenses
The initial treatment and control lenses were selected according to protocol guidelines and then adjusted to achieve an optimal fit based on lens position movement and alignment as assessed by fluorescein study At the outset the treatment and control lenses differed in that the treatment lenses were on the average thicker and flatter and had a larger diameter
Following the dispensing visit subjects progressed through three study phases In the adaption phase Phase A subjects were examined weekly until they were adapted to 12 to 14 hours of daily contact lens wear The postadaptive phase Phase B consisted of monthly followup examinations for 1 year The final phase Phase C consisted of a lens withdrawal segment and a postwearing segment
The Berkeley Orthokeratology Study was a single center randomized concurrently controlled masked clinical trial Corneal and visual changes in an orthokeratology treatment group were monitored and compared with those observed in a control group whose members wore contact lenses fitted in a standard clinical manner Visual and ocular characteristics were monitored for 15 years
Eighty subjects were studied-40 in an orthokeratology group and 40 in a control group fitted with conventional hard contact lenses The hard lenses chosen for this study were made of either polymethyl methacrylate PMMA or a PMMA-silicone combination Polycon All subjects were initially fitted with PMMA lenses
The initial treatment and control lenses were selected according to protocol guidelines and then adjusted to achieve an optimal fit based on lens position movement and alignment as assessed by fluorescein study At the outset the treatment and control lenses differed in that the treatment lenses were on the average thicker and flatter and had a larger diameter
Following the dispensing visit subjects progressed through three study phases In the adaption phase Phase A subjects were examined weekly until they were adapted to 12 to 14 hours of daily contact lens wear The postadaptive phase Phase B consisted of monthly followup examinations for 1 year The final phase Phase C consisted of a lens withdrawal segment and a postwearing segment
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