Intrastromal Presbyopia Correction by Means of a Femtosecond Laser

This clinical study is an open, prospective, multi-centre eye study consisting of three study arms to determine the safety and efficacy of intrastromal incisions for the correction of visual acuity on presbyopic eyes. The incisions are applied by means of the FEMTEC femtosecond laser system with the INTRACOR software module using patterns consisting of 6 concentric rings and 3 different inner ring diameters. A similar pattern with 5 concentric rings and only one fixed inner diameter is currently under clinical investigation.

The hypothesis of the study is that by means of intrastromal incisions, near visual acuity can be improved in presbyopic eyes in a safe and effective way.

The intrastromal incisions are performed by the femtosecond laser FEMTEC, which is CE certified for various therapeutic indications. The incision eliminates both an epithelial and an endothelial opening of the cornea whereby the minimally invasive character of this form of treatment is guaranteed. A detailed pre-operative examination will ensure that every interested and willing patient fulfils the inclusion criteria of this study. Post-operative examinations, which should document the success of the treatment, are to be carried out after 24 hours, 1 week, 1 month, 3 months and 6 months.

Inclusion criteria

• Age: at least 18 years old
• Patients must have read, understood and signed the Patient Information
• Patients are willing and able to return for follow-up examinations
• Stable distance refraction
• Manifested Refraction (see Table 1 for more details) :

• Cylinder: -0.5 D to 0 D
• Sphere: 0.25 D to 1.25 D
• Spherical equivalent: Minimum 0.25 D
• Best corrected distance visual acuity of the eye to be treated at least 0.8
• Subjects must have presbyopia as determined by an age-related need for optical aid (≥ +1.5 D) for reading with their best distance correction.

Exclusion criteria

• Minimum cornea thickness < 500 µm
• Ocular dominance (only non-dominant eyes should be included)
• Uncorrected Near Visual Acuity of 0.5 or better
• Difference between manifested and cycloplegic refraction of > 0.75 D in spherical equivalent
• Median K values < 40 D or > 46 D
• Topographical astigmatism > 5 D
• Abnormal corneal topography
• Patients with previous corneal operations on the eye to be treated (e.g. LASIK, PRK, X-Linking; this does not include cataract operations)
• Scarring or opacity of the cornea
• Transplanted cornea
• Connective tissue weaknesses
• Keratectasia and other diseases of the cornea
• Patients with wound-healing disorders such as connective tissue disease, autoimmune illnesses, immunodeficiency illnesses, ocular herpes zoster or simplex, endocrine diseases, lupus, rheumatoid arthritis
• Patients regularly taking medicines that could influence the result of the treatment
• Glaucoma or a risk of glaucoma
• Patients with concentration disorders, epilepsy, diabetes mellitus and other complicating diseases
• Patients with disorders of the ocular muscle, such as nystagmus or strabismus
• Sensitivities to the drugs used in this study
• Continual wearing of contact lenses before the pre-examination and before the operation. Patients must refrain from wearing contact lenses for at least 14 days prior to these dates
• Patients who are pregnant or are lactating
• Patients who are participating in another ophthalmological clinical study
• Best corrected distance visual acuity of the second, not to be treated eye is 0.5 or less.