Cataract, Corneal Astigmatism, Corneal Incision Contracture
Conditions
Keywords
surgically induced astigmatism, phacoemulsification, bimanual microincision cataract surgery, coaxial microincision cataract surgery, small incision cataract surgery, clear corneal incision
Brief summary
The aim of the study is to compare functional results and complications of 3 methods of cataract phacoemulsification: bimanual 1.4 mm cataract surgery (B-MICS), coaxial 1.8 mm cataract surgery (C-MICS) and coaxial 2.4 mm small incision cataract surgery.
Detailed description
Reduction of the width of the corneal incision was one the main changes taking place in cataract surgery in recent years. The common use of foldable intraocular lenses (IOLs) and technological development of phaco machines allowed to reduce clear corneal incision below 3 mm. Term of Microincision Cataract Surgery (MICS) understood as cataract phacoemulsification performed with the incision width below 2 mm was defined by professor Alio in 2003. However, despite various modifications introduced in recent years, phacoemulsification still causes damage of the tissues that results in surgically induced astigmatism. Two MICS techniques have been developed: bimanual microincision cataract surgery (B-MICS) and coaxial microincision cataract surgery (C-MICS). In the bimanual technique cataract phacoemulsification can be performed through the main incision 1.4 mm wide due to the usage of sleeveless phaco tip (without irrigation) and irrigation chopper. The advantage of separation the irrigation from aspiration is improvement of liquid dynamics in the anterior chamber. Moreover, due to the usage of the irrigation chopper, in B-MICS it is possible to lower the mean ultrasound energy. In coaxial technique MICS phacoemulsification is performed through the incision 1.8 mm wide with usage of phaco tip with a silicon irrigation sleeve. The aim of the study is to compare functional results and complications of 3 methods of cataract phacoemulsification: bimanual 1.4 mm cataract surgery (B-MICS), coaxial 1.8 mm cataract surgery (C-MICS) and coaxial 2.4 mm small incision cataract surgery. Moreover, this study aimed to evaluate the impact of corneal width on best corrected visual acuity (uncorrected and corrected), surgically induced astigmatism, endothelial cell loss, intraocular pressure, anterior segment of the eye and central retinal thickness.
Interventions
PROCEDUREBimanual 1.4 mm microincision cataract surgery (B-MICS) with IOL implantation in a wound-assisted technique. In bimanual MICS group a self-sealing 1.4 mm wide incision was created supratemporally
microincision cataract surgery (phacoemulsification) with implantation of a foldable, acrylic, hydrophilic IOL Incise® MJ14, Bausch & Lomb
PROCEDURECoaxial 1.8 mm microincision cataract surgery (C-MICS) with IOL implantation with an injector through the 1.8 mm wide incision created temporally.
microincision cataract surgery (phacoemulsification) with implantation of a foldable, acrylic, hydrophilic IOL Incise® MJ14, Bausch & Lomb
PROCEDURECoaxial 2.4 mm small incision cataract surgery (C-SICS) with IOL implantation with an injector through the 2.4 mm wide incision located temporally.
small incision cataract surgery (phacoemulsification) with implantation of a foldable, acrylic, hydrophilic IOL Incise® MJ14, Bausch & Lomb
Sponsors
Medical University of Lodz
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
35 Years to 87 Years
Healthy volunteers
No
Inclusion criteria
* lens opacities which were an indication for cataract surgery and absence of
Exclusion criteria
, * cataract sclerosis grade from II to IV in Lens Opacities Classification System LOCS III scale (The Lens Opacities Classification System III).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| parafoveal retinal thickness | 36 months | measured with Optical Coherence Tomography (OCT), unit of measure: µm (micrometers) |
| the best corrected visual acuity | 36 months | examined with digital Snellen chart, measured in decimal scale |
| the best uncorrected visual acuity | 36 months | examined with digital Snellen chart, measured in decimal scale |
| autorefractometry | 36 months | measured in diopters (D) |
| keratometry | 36 months | measured in diopters (D) |
| intraocular pressure (IOP) | 36 months | measured in millimeters of mercury (mmHg) |
| endothelial cell density (ECD) | 36 months | measured in endothelial cells/mm2 |
| central corneal thickness (CCT) | 36 months | measured with Anterior Segment Optical Coherence Tomography (AS-OCT), unit of measure: µm (micrometers). |
| peripheral temporal corneal thickness | 36 months | measured at the main incision site with Anterior Segment Optical Coherence Tomography (AS-OCT), unit of measure: µm (micrometers) |
| peripheral nasal corneal thickness | 36 months | measured with Anterior Segment Optical Coherence Tomography (AS-OCT), unit of measure: µm (micrometers) |
| anterior chamber depth (ACD) | 36 months | measured with Anterior Segment Optical Coherence Tomography (AS-OCT) in mm (milimeters). |
| the white-to-white (WTW) distance - the horizontal corneal diameter | 36 months | measured with Anterior Segment Optical Coherence Tomography (AS-OCT, unit of measure: mm (milimeters). |
| length of the clear corneal incision | 36 months | the chord length measured with Anterior Segment Optical Coherence Tomography (AS-OCT), unit of measure: µm (micrometers) |
| anterior chamber angle | 36 months | measured with Anterior Segment Optical Coherence Tomography (AS-OCT) in horizontal scan, unit of measure: degrees |
| central foveal thickness (CFT) | 36 months | measured with Optical Coherence Tomography (OCT), unit of measure: µm (micrometers) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| surgically induced astigmatism SIA | 36 months | measured in dioptres (D) - three different methods were used for calculation of surgically induced astigmatism (SIA): vector analysis method, vector decomposition method (C90), Naeser's polar values method (dKP-90) |
Outcome results
None listed