Cataract surgery is the most commonly performed operative procedure today with phacoemulsification being universally accepted as the best method of cataract extraction (Vajpayee 1999). Phacoemulsification has the advantages of small incision and early visual rehabilitation. However, phacoemulsification has been considered relatively unsuitable for challenging case such as hypermature cataracts (Vajpayee 1999) and intumescent white cataracts (Conrad-Hengerer 2014) because these cases may have increased intracapsular pressure due to liquefaction of the cortex and a hard or brunescent nucleus underlying an anterior/posterior cortical opacity. In intumescent cataracts, the structural causes of tensile weakness were confirmed with ultra-structural analysis of the anterior capsule of the intumescent cataract. While the analysis showed no increase in thickness, it did indicate extrusions of basement membrane filaments at the basement membrane epithelial border, rarefication, perpendicular lucent areas with fibrillary material and lamellae (Hawlina 2011). These findings represent weak points for capsular stretching, pressure, longitudinal splitting along the lamellae and tearing to the periphery. Therefore, the most difficult step of cataract surgery in these cases is the creation of a continuous capsulorhexis without further anterior capsule complication The introduction of femtosecond laser for ophthalmic application provides another method for cutting tissues within the eye. These lasers have been used in ophthalmology for many years. The most common application is for the creation of corneal flaps but in recent years the technology has been introduced in cataract surgery. The femtosecond laser assists with all the key steps in cataract surgery prior to phacoemulsification namely: creation of corneal incisions, anterior capsulotomy and lens fragmentation (Roberts 2013). Phacoemulsification requires the creation of a manual capsulotomy using a surgical cystotome to puncture the capsular bag. This procedure, known as continuous curvilinear capsulorrhexis (CCC), can be associated with extension of the torn capsular edge. Such tears weaken and compromise the integrity of the capsule and may lead to vitreous loss, and the inability to safely place a posterior chamber IOL. The rate of such complications, about 1%, is not insignificant (Marques 2006). Phacoemulsification requires the creation of a manual capsulotomy using a surgical cystotome to puncture the capsular bag. This procedure, known as continuous curvilinear capsulorrhexis (CCC), can be associated with extension of the torn capsular edge. Such tears weaken and compromise the integrity of the capsule and may lead to vitreous loss, and the inability to safely place a posterior chamber IOL. The rate of such complications, about 1%, is not insignificant (Marques 2006). The aim of LenSx Laser is to apply the known safety and accuracy of femtosecond lasers, combined with OCT targeting, to cataract surgery. Considering the features offered by the LenSx Laser, the following device benefits are balanced against the risks mentioned above. • For capsulotomy, the LenSx Laser produces anterior capsulotomy whose sizes are statistically more uniform, accurate, and predictable than those produced by manual techniques. By providing well-centered and uniform capsulotomy, the placement and performance of IOL’s is expected to improve. • For corneal incisions, the benefit of femtosecond laser treatment is well understood. The LenSx Laser extends these benefits to the creation of uniform, surgeon-chosen corneal incisions for cataract surgery. In challenging cases such as patients with intumescent cataracts where visibility of the capsule can be compromised, this can provide a significant benefit to complete the most difficult step with minimal risk. In addition, it allows the surgeon to create a customized multi-plane corneal incision that will be challenging to create manually
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