December 2, 2019 | Author: Admin
Cataract surgery is probably one of the most ancient surgeries done by humans. In the initial days the surgery done was known as couching. The procedure of Couching, unlike today, was done in the patients who have a completely opaque lens, which becomes rigid and subsequently so heavy that fragility occurs in the supporting zonules. The techniques evolved from the past and it was in 1748, the first surgical removal of cataract was done. The development of anesthesia plays a major role in the evolution of this surgery.
From then to now, the technology used in cataract surgery becomes advanced and safe. Too much has been changed, particularly in this arena of medical science, in the last decade or so. The perception regarding the procedure has been completely changed. Previously, the patient keeps on delaying the cataract surgery due to the fear of post-operative complications, partial or complete vision loss, reduction in quality of vision and occurrence of high postoperative astigmatism.
The technology used in cataract surgery takes a quantum leap when an ophthalmologist removes the cataract by keeping the lens capsule intact. From intracapsular cataract extraction to extracapsular cataract extraction to Phacoemulsification, the size of incision becomes small with an increase in the safety of the procedure. At present, the use of Femtosecond laser surgery is on the rise and the cataract patients are also infusing their confidence in the advanced technology. LenSx lasers (Aliso Viejo, Calif.) are approved by the FDA to create an anterior capsulotomy and corneal incision and for phaco fragmentation.
Not only the technology for Cataract has been replaced but the IOL calculations methodology has also seen a drastic change and has been replaced by fourth-generation formulas and inclusion of biometry. Facts in the history defines that the cataract surgery was done to allow the patient to perform his work but in today’s demanding world, the enhanced vision after the cataract surgery defines the quality of life. Patients are not settling for anything less and desire the perfect vision.
One of the important problems that are faced by modern technology for cataract is the management of astigmatism. Some ophthalmologists find it normal for having small astigmatism after surgery as they might believe that astigmatism may help in improving in-depth near vision. However, it is also to be noted that post-operative astigmatism, in all cases of distant vision, reduces the quality of vision. Presbyopic IOLs develop increased astigmatism as compared to other types of IOLs. During the cataract surgery, astigmatism may develop due to preoperative posterior corneal astigmatism, preoperative anterior corneal astigmatism, surgically induced corneal astigmatism, or mal-positioned IOL. These all sources of astigmatism may occur simultaneously or in isolation. With the advanced technology for cataract surgery and more sophisticated measurement techniques, the ophthalmologists are now in a better position to counter the occurrence of astigmatism.
According to a study, more than 50% of the patients undergoing cataract surgery have developed astigmatism of 0.75 D or more. It has also been found that although patients may effectively adjust the astigmatism of 0.5 D they are not al all ready to settle for anything less than the perfect vision. 0.5 D astigmatism can easily be settled by wearing glasses but the ophthalmologists are finding themselves in treating this range of astigmatism.
Many ophthalmologists still believe that small refractive errors are tolerable but the other side i.e. the patients are not in the mood to accept this belief. Thus, the onus is on the surgeon to fine-tune the surgical process and reduce the occurrence of any refractive error during the surgery. There is a need for translation of ophthalmologists from the cataract surgeon to a refractive cataract surgeon to meet the expectation of the patients. This means surgically hitting the right mark and preventing and treating astigmatism.
Geetha Davis, MD. The Evolution of Cataract Surgery, Mo Med. 2016 Jan-Feb; 113(1): 58–62.
Ferrer-Blasco T, et al. Prevalence of corneal astigmatism before cataract surgery. J Cataract Refract Surg. 2009;35:70–5.