Refractive lenticule extraction is becoming the procedure of choice for the management of myopia and myopic astigmatism owing to its precision, biomechanical stability, and better ocular surface. It has similar safety, efficacy, and predictability as femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and is associated with better patient satisfaction. The conventional technique of small incision lenticule extraction (SMILE) involves docking, femtosecond laser application, lenticule dissection from the surrounding stroma, and extraction. It has a steep learning curve compared to conventional flap-based corneal ablative procedures, and the surgical technique may be challenging especially for a novice surgeon. As SMILE is gaining worldwide acceptance among refractive surgeons, different modifications of the surgical technique have been described to ease the process of lenticule extraction and minimize complications. Good patient selection is essential to ensure optimal patient satisfaction, and novice surgeons should avoid cases with low myopia (thin refractive lenticules), difficult orbital anatomy, high astigmatism, or uncooperative, anxious patients to minimize complications. A comprehensive MEDLINE search was performed using “small incision lenticule extraction,” “SMILE,” and “refractive lenticule extraction” as keywords, and we herein review the patient selection for SMILE and various surgical techniques of SMILE with their pros and cons. With increasing surgeon experience, a standard technique is expected to evolve that may be performed in all types of cases with optimal outcomes and minimal adverse effects.

Toric intraocular lenses (IOLs) are the procedure of choice to correct corneal astigmatism of 1 D or more in cases undergoing cataract surgery. Comprehensive literature search was performed in MEDLINE using “toric intraocular lenses,” “astigmatism,” and “cataract surgery” as keywords. The outcomes after toric IOL implantation are influenced by numerous factors, right from the preoperative case selection and investigations to accurate intraoperative alignment and postoperative care. Enhanced accuracy of keratometry estimation may be achieved by taking multiple measurements and employing at least two separate devices based on different principles. The importance of posterior corneal curvature is increasingly being recognized in various studies, and newer investigative modalities that account for both the anterior and posterior corneal power are becoming the standard of care. An ideal IOL power calculation formula should take into account the surgically induced astigmatism, the posterior corneal curvature as well as the effective lens position. Conventional manual marking has given way to image-guided systems and intraoperative aberrometry, which provide a mark-less IOL alignment and also aid in planning the incisions, capsulorhexis size, and optimal IOL centration. Postoperative toric IOL misalignment is the major factor responsible for suboptimal visual outcomes after toric IOL implantation. Realignment of the toric IOL is needed in 0.65%–3.3% cases, with more than 10° of rotation from the target axis. Newer toric IOLs have enhanced rotational stability and provide precise visual outcomes with minimal higher order aberrations.

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Purpose: To evaluate morphological characteristics and intraoperative dynamics of different types of white cataract using intraoperative optical coherence tomography (iOCT). Setting: Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India. Design: Prospective interventional study. Methods: Fifty eyes with white cataract undergoing phacoemulsification were evaluated. The primary outcome measure was the classification of white cataract based on morphology and intraoperative dynamics on iOCT. The secondary outcome measure was rhexis-related complications. Results: Four types of white cataract were identified based on iOCT—type I (9 eyes), type II (3 eyes), type III (24 eyes), and type IV (14 eyes). Type I had regularly arranged lamellar cortical fibers, type II had continuous hyperreflective bands of cortical fibers with intralenticular clefts, type III had intralenticular clefts combined with areas of homogenous ground-glass appearance, and type IV had homogenous ground-glass appearance of the anterior lens cortex. Capsulorhexis in type I cataract was uneventful. In type II cataract, cortical bulge was observed in the anterior chamber on creating the initial nick, indicating raised intralenticular pressure (ILP) with an imminent risk of rhexis extension. A bimanual irrigation/aspiration was performed until lowering of ILP was observed on iOCT. In types III and IV, fluid release was observed on initiation of rhexis leading to partial (type III) or complete (type IV) lowering of ILP, with a mild-moderate risk of capsulorhexis extension. A continuous curvilinear capsulorhexis was achieved in all cases, with no case of posterior capsular tear or vitreous loss. Conclusions: Intraoperative OCT helped elucidate intraoperative dynamics of the spectrum of white cataracts and facilitates completion of capsulorhexis.

A 6.5-year-old boy with congenital hereditary endothelial dystrophy underwent clear corneal ultra-thin descemet stripping automated endothelial keratoplasty (DSAEK). After graft insertion, it was difficult to assess graft orientation due to hazy cornea. Intraoperative optical coherence tomography (iOCT) showed a well-attached graft and the bevelled edge of donor lenticule made an acute angle with the overlying stroma. Postoperative anterior segment OCT confirmed the presence of acute-angled bevel sign. A wetlab experiment was performed with experimental corneoscleral tissues to confirm the findings. Donor lenticule was injected in the artificial chamber with stromal-side up as well as stromal side-down. ‘Acute-angled bevel sign’ was observed on iOCT in the experimental cases with stromal-side up. In inverse graft, the acute-angled bevel was not observed, instead the configuration was obtuse angled. Identifying the ‘acute-angled bevel sign’ on iOCT confirms correct graft orientation after unfolding and is extremely useful for hazy corneas and ultrathin DSAEK lenticules.