Intacs for Keratoconus
试验速览
- 阶段
- 不适用
- 入组人数
- 20
- 试验地点
- 2
- 主要终点
- Visual acuity
研究概览
简要总结
To study the effects Intacs intracorneal ring segments(Addition Technology, Inc) insertion in the treatment of keratoconus
详细描述
The purpose of this evaluation is to study the effects of implanting INTACS inserts, identical to those commercially available to correct myopia, into the corneal stroma of patients with keratoconus (mild to moderate) and having a clear cornea. The principle of the procedure is to flatten the cornea deformed by keratoconus. One or two segments of the same or a different thickness will be selected to reduce the asymmetric astigmatism responsible for the patient impaired visual acuity.
The surgical technique is based on locating the INTACS inserts on the flattest axis of the refractive error, making the incision on the steepest axis, using 150 degree arc length inserts with different sizes (0.250, 0.300, 0.350, 0.400 & 0.450 mm) according to a nomogram designed for this technique using the INTACS Instrumentation (10-Step Prolate System instruments).
The corneal lamellar channel creation may be performed using the INTACS instrumentation or using the Femtosecond laser (Femtec 20/10 laser[Femtec,Heidelberg Germany])
Primary Assessment Criteria
- Evaluation of the safety of the device for the treatment of patients with keratoconus (mild to moderate)
- Maintenance of best corrected visual acuity (BCVA)
- Improvement in uncorrected visual acuity (UCVA)
- Reduction in manifest refraction spherical equivalent
- Reduction in asymmetric astigmatism
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 21 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Patients must have keratoconus (mild to moderate).
- •Visual acuity with contact lenses must be better than or equal to (20/40).
- •Patients must be intolerant of contact lenses, i.e., they must be unable to wear contact lenses for a whole day.
- •Patients will have a corneal thickness of 425 microns at the site of ICRS (INTACS inserts) placement (the thinnest region of the cornea).
- •In terms of general health, patients must not have any illnesses posing an immediate threat to life.
- •Patients must have provided written informed consent at least one week prior to surgery.
- •Patients must over 21 years of age.
- •Patients' contact lenses must have been removed at least one week prior to surgery for soft lenses and two weeks prior to surgery for hard lenses.
排除标准
- •Positive pregnancy test.
- •Breast-feeding.
- •History of previous ophthalmologic surgery on the operative eye.
- •Patients with corneal stromal disorders.
- •Patients with history of herpetic keratitis.
- •Patients with retinal disorders.
- •Corneal grafts.
- •Patients refusing to remove contact lenses one week before surgery for soft lenses and two weeks before surgery for hard lenses.
- •Patients with amblyopia (VA <1110 for the contralateral eye).
- •Patients with corneal thickness <425 microns.
- •Patients with TOP <10 mmHg or >21 mmHg.
- •Patients taking part in other biomedical research in the 30 days prior to the start of this study.
- •Patients with an uncooperative disposition.
结局指标
主要结局
Visual acuity
Refraction
Corneal topography
次要结局
- Patient satisfaction following procedure