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Purpose: To identify pitfalls and offer hints on achieving a successful outcome during the early laser in situ keratomileusis (LASIK) learning process., Setting: Gimbel Eye Centre, Calgary, Alberta, Canada., Methods: This was a retrospective review of the preoperative planning, surgical procedure, intraoperative and postoperative problems, and early postoperative anatomic and refractive results in the first 73 eyes that had LASIK., Results: Intraoperative complications included failure of the keratome to make a cut, excessively thin cap, repositioning difficulty, and inadequate intraocular pressure elevation. Early postoperative complications included excessive central and peripheral wrinkling of the cap, peripheral lipid deposits, and central edema of the cap. One month postoperatively, mean spherical equivalent refraction was -0.90 diopters (D) (range +1.75 to -6.00 D), and 45 eyes had a best corrected visual acuity between 20/15 and 20/40., Conclusion: Our retrospective review of the problems experienced during the early LASIK learning process should help novice lamellar refractive surgeons avoid such problems and shorten the learning curve.

Jeffrey Ma,1,2 Chintan Pathak,1 Abhijit Ramaprasad,1 Surendra Basti1 1Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; 2Department of Ophthalmology, UC Davis Eye Center, University of California Davis, Sacramento, CA, USACorrespondence: Surendra BastiDepartment of Ophthalmology, Feinberg School of Medicine, Northwestern University, 645 North Michigan Avenue, Suite 440, Chicago, IL, 60611, USATel +1 312 908 8152Fax +1 312 503 8152Email sbasti@northwestern.eduPurpose: To assess the efficacy of IOLMaster 700 (IOLM) biometer swept-source optical coherence tomography (SS-OCT) in detecting macular pathology before cataract surgery and to compare IOLM SS-OCT characteristics of foveal pathology with a widely used spectral-domain OCT (SD-OCT) system.Patients and Methods: Retrospective analysis of 1156 consecutive eyes with IOLMaster 700 SS-OCT undergoing cataract surgery from January to June 2017 was performed. Approximately a third of these eyes (327 eyes) also had a SD-OCT scan performed previously. A single reviewer assessed each SS-OCT scan and identified them as “normal” or “abnormal.” SS-OCT sensitivity and specificity in identifying foveal pathology was assessed using findings on Spectralis SD-OCT scans as the gold standard.Results: Of 327 eyes with both IOLM SS-OCT and Spectralis SD-OCT scans, 121 eyes (37.0%) had abnormal SS-OCT scans. Of these 121 eyes, SD-OCT scans confirmed pathology in 104 eyes (86.0%). Of the remaining 206 eyes graded to have normal SS-OCT scans, 84 eyes (40.8%) had normal SD-OCT scans, and 122 eyes (59.2%) had pathologic findings on SD-OCT scans. For each pathologic condition, subtle but definitive differences existed in the appearance of the IOLM SS-OCT and SD-OCT images.Conclusion: Using a normal or abnormal Spectralis SD-OCT scan as confirmation of absence or presence of foveal pathology respectively, we found a high positive predictive value (86.0%) of an abnormal IOLM SS-OCT scan and a high specificity (83.2%) but low sensitivity (46.0%) and negative predictive value (40.8%) of a normal-appearing SS-OCT scan. These results suggest that an abnormal IOLM SS-OCT scan in an eye without known pathology is a strong indicator of an abnormal macula and should prompt further evaluation of the retina to identify pathology prior to cataract surgery. Importantly, IOLM SS-OCT scans do not detect all macular pathology and cannot be used as a screening test for identifying macular pathology.Keywords: optical biometry, macular OCT, cataract surgery preoperative testing

The past two decades have witnessed remarkable progress in limbal stem cell transplantation. In addition to harvesting stem cells from a cadaver or a live related donor, it is now possible to cultivate limbal stem cells in vitro and then transplant them onto the recipient bed. A clear understanding of the basic disease pathology and a correct assessment of the extent of stem cell deficiency are essential. A holistic approach towards management of limbal stem cell deficiency is needed. This also includes management of the underlying systemic disease, ocular adnexal pathology and dry eye. Conjunctival limbal autografts from the healthy contralateral eye are performed for unilateral cases. In bilateral cases, tissue may be harvested from a cadaver or a living related donor; prolonged immunosuppression is needed to avoid allograft rejection in such cases. This review describes the surgical techniques, postoperative treatment regimes (including immunosuppression for allografts), the complications and their management. The short and long-term outcomes of the various modalities reported in the literature are also described.

As we near the end of this century, refractive cataract surgery has become a reality through concerted contributions from ultrasonic phacoemulsification, foldable intraocular lens (IOL) implantation technology and keratorefractive surgery. As we enter the new millennium, our sights are set on realizing another dream: accommodative IOL surgery. Towards achieving this goal, many advances have been made in both techniques and technology of cataract removal. Lasers in particular have been under investigation for cataract removal for nearly two decades. The technology has now reached a stage where cataract can indeed be removed entirely with laser alone. Neodymium:YAG and erbium:YAG are the laser sources currently utilized by manufacturers of laser phaco systems. Initial clinical experience reported in the literature has served to highlight the capabilities of lasers and the need for further refinement. Despite the excitement associated with the availability of this alluring new technology for cataract removal, it is necessary to develop more effective laser systems and innovative surgical techniques that optimize its capabilities if laser phaco surgery is to be a genuine improvement over current techniques.

A clear understanding of the physical and mechanical principles that govern phacoemulsification can facilitate usage of this technique for effective and efficient cataract removal in a variety of clinical situations. This article addresses separately, concepts pertaining to the three essential components of phacoemulsification, namely, irrigation, aspiration and emulsification. Machine settings are suggested for the various techniques presently in use. Finally, alternative approaches for lens removal that are currently being investigated are briefly discussed.

Corneal persistent epithelial defects (PED) can occur due to various causes. In diffuse ocular surface disease, they often occur secondary to depletion of limbal stem cells. A number of complications occur secondary to PED and successful treatment usually requires conjunctival surgeries for corneal surface reconstruction. We report two cases of chemical injury successfully treated by two such procedures. This report highlights the encouraging results of limbal transplantation and reviews the literature in the management of PED with limbal stem cell loss.

Propensity for increased postoperative inflammation and capsular opacification, a refractive state that is constantly in a state of flux due to growth of the eye, difficulty in documenting anatomic and refractive changes due to poor compliance, and a tendency to develop amblyopia, makes management of cataract in the child different from that in the adult. The recent past has unraveled several caveats of pediatric cataract management - the importance of atraumatic surgery and complete removal of lens matter, benefits of in-the-bag intraocular lens(IOL) implantation, role of titrating IOL power to counter refractive changes due to growth of the eye, prudery of continuously following these eyes for early detection of aphakic glaucoma and benefits of some surgical innovations. Although these promise to significantly improve our management of pediatric cataract, their long-term benefits are yet to be determined. We will also have to harness newer techniques, especially in the areas of wound construction and capsule management, and will have to develop effective strategies for the refractive management of infantile aphakia.