Résumé
Background: In LASIK (laser in situ keratomileusis), a hinged corneal flap is made, which enables the flap to be lifted and the excimer laser to be applied to the stromal bed. If the hinge of the corneal flap detaches from the cornea, the flap is called a free cap. A free cap is a rare intra-operative complication of LASIK most commonly associated with the use of a microkeratome on corneas with flat keratometry, which predisposes to a small flap diameter. Free caps are preventable and treatable. Rarely does the complication lead to a severe or permanent decrease in visual acuity. Purpose: As free caps are avoidable, prevention is critical. Our video gives some tips and tricks on how to avoid a free flap and also focuses on how to manage a cut through a free flap. Synopsis: If a free cap is created, the surgeon must decide whether to continue with excimer laser ablation or to abort the procedure. When to abort: If the stromal bed is irregular, the flap is replaced without applying laser ablation. Without ablation, generally, there is no change in refractive error or significant loss of visual acuity. When to continue: If the stromal bed is regular and the cap is of normal thickness, the surgeon may proceed with ablation. To prevent desiccation, the free cap should be handled with caution and should be placed on a drop of balanced salt solution. The free cap should be placed epithelial facing up, along with a bandage contact lens. The endothelial cell pump mechanism typically allows the cap to re-adhere tightly. Highlights: Risk factors for a free cap are generally anatomic or mechanical. Especially in flat corneas, an appropriate ring and stop size should be chosen looking at the nomogram on the basis of the keratometry values. Deep orbits and deep-seated eyes should be looked for as PRK is a better option in such cases. Inadequate suction should be dealt with a lot of care, and once this is done, the vacuum should be stopped. Re-docking of the microkeratome with suction can be done again. Prior testing of the microkeratome and a good verbal anesthesia are a few more such important points to be pondered upon. This video gives us such tips and is a comprehensive video for a novice surgeon performing microkeratome LASIK
Résumé
Background: With about 87% of patients with cataracts having astigmatism, management of astigmatism in cataract surgery not only yields an improved unaided visual acuity and image quality but also higher patient satisfaction. The video will give a step?wise guide to cataract surgeons to manage astigmatism with cataracts. Purpose: To hit the bull’s eye as far as target refraction is concerned, it is necessary to understand the benefits and limitations of currently available cutting?edgetechnology and formulae and apply them to the cataract surgery practice. The purpose of the video is to make sure that we have no surprises in our Toric intraocular lens (IOL) planning. Synopsis: After a brief introduction to available modalities for the treatment of astigmatism, a step?wise approach to diagnostics is discussed, which will include the role of corneal topography and aberrometers and their application to planning Toric IOLs. Appropriate planning, implementation, and execution in form of preoperative and intraoperative pearls of using Toric IOLs are shown in the video. This will be followed by troubleshooting and case?based discussions and future perspectives including the possible role of corneal biomechanics. Highlights: What this video adds new is the importance of topography, interpretation of Belin?Ambrosio display map and the equivalent keratometry reading (EKR) map, aberrometry, and higher order aberration (HOA) analysis and role of biomechanics in Toric IOL planning. Video also highlights the importance of posterior corneal astigmatism and accurate axis marking. With a case?based approach and relevant examples, we are trying to decipher the enigma of astigmatism by giving a step?wise approach for the same