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All Cornea 36 Cataract 17 Glaucoma 13 Retina & Vitreous 72 Neurophthalmology 8 Oculoplasty 15 Uvea & Inflammatory Diseases 24 Miscellaneous 20 Oncology 9 Pediatric Ophthalmology 15

20 Jul 2021 10 min read

Ocular Oncology Basics: Diagnosis of Intraocular Malignancies

“Declare the past, diagnose the present, foretell the future.” Hippocrates In this section, I will deal with various diagnostic methods which are common in practice for the diagnosis of mainly Intraocular malignancies. Diagnostic modalities used for extraocular malignancies will be considered in the respective chapters. 1.History Even though the twenty-first century has seen a boom in the diagnostic armamentarium available to the ophthalmologist, the art of good history taking can never be out of fashion. History of the present complaints, their duration, and associated complaints can provide multiple clues. If the duration of complaints has been seen over a long period of time with minimal change; a chronic condition can be anticipated. A sudden change in vision is an alerting sign. Personal history pertaining to the patient's occupation will provide us the visual needs of the concerned. Any previous history of other malignancies, its treatment history may provide clues with the etiol

Dr. Bikramjit Pal
20 Jul 2021 6 min read

Ocular Oncology Basics: Salient Points from The Pandora's Box

RETINOBLASTOMA Grouping: Clinical determination of the extent of disease with the focus being the eye. It is a preoperative evaluation with the main outcome being the salvagable status of vision or the eye. Staging: It combines clinical, various imaging, and post-operative histopathological results to determine the extent of the disease. The main outcome is focused on the survival of the patient. International Classification of Retinoblastoma ( grouping) [1] Group A: Tumours smaller than 3mm or less Should be 2DD ( 3mm) from the fovea Should be 1DD (1.5mm) from optic nerve head Group B: Tumours bigger than those in group A Located within 2DD from the fovea Located within 1DD from optic nerve head Localized cuff of subretinal fluid( < 5mm) No seeding is allowed in the group. Group C: Localized tumor dissemination Vitreous seeding not more than 3mm from the base of tumor Subretinal seeding not more than 3mm from the base of tumor Group D: Diffuse tumor dissemination Vitreous seeding may

Dr. Bikramjit Pal
20 Jul 2021 8 min read

Ocular Oncology Basics: Genetics

Twenty first century has seen a giant leap in the understanding of human genetics. Based on the human genome project humans are supposed to have roughly 20,000 to 25,000 genes. Genes are the fundamental units of heredity. To understand genetics involved in various ocular pathologies a basic understanding is essential. The following discussion will provide an overview of basic concepts in genetics and provide a glimpse into the genetics of Retinoblastoma and intraocular melanoma. The basic structure of a chromosome [1] Chromosomes are formed by a tight packaging of the DNA stored in the nucleus of a cell Each gene in humans are comprised of 2 copies ; one inherited from either parent. Forms of the same gene with differences on the basis of bases are known as alleles. A tightly regulated process of transcription and translation involves the production of basic building blocks called as amino acids to form proteins. Gene regulation is the process whereby certain genes are 'switched on' an

Dr. Bikramjit Pal
20 Jul 2021 13 min read

Ocular Oncology Basics: Treatment Strategies In Intraocular Malignancies

“Cancer can take away all of my physical abilities. It cannot touch my mind, it cannot touch my heart, and it cannot touch my soul.” Jim Valvano Treating malignancies I believe, brings the true human spirit forward of the treating physician. Breaking the news of malignancy to a patient is as heartbreaking for the physician as it is for the patient. Yet the doctor must keep his feelings aside and do his best. Even though the human eye forms a small fraction of the human body, malignancies of all sorts and sizes can be found inside. Treatment is complex and takes a lifetime to master. In this section, I will summarize the various treatment modalities used in intraocular malignancy with a small write-up on chemotherapy and radiotherapy. 1. CRYOTHERAPY Principle of cryotherapy [1],[2] Direct effect Indirect effects: Initial freezing causes vasoconstriction and then the process of thawing causes vasodilation leading to increased permeability and edema Secondary endothelial damage leads to f

Dr. Bikramjit Pal
20 Jul 2021 12 min read

Ten Pearls for the Management of Posterior Capsular Rupture

Posterior capsular rupture (PCR) is an important complication of cataract surgery whose timely recognition and appropriate management can ensure a good visual outcome. Here are ten pearls for its prevention and management. Pearl 1: Understand the risk/predisposing factors It is imperative to assess the preoperative and intra-operative risk to prevent the development of a PCR. Elderly, anxious, and uncooperative patients are at a higher risk of developing posterior capsular rupture. Extraocular factors include a deep socket, narrow palpebral fissures, exaggerated bell’s phenomenon, hazy cornea, and intraocular factors are poor mydriasis, shallow or excessively deep anterior chamber, pseudoexfoliation, and type of cataract (like posterior polar, traumatic, post-intravitreal injections, intumescent or hard cataract), previous vitrectomy or oil-filled eyes. Surgical factors like inexperience of the surgeon, leaking incisions, small capsulorhexis, radial tears in rhexis, fluid imbalance in

Dr. Arup Chakrabarti · Dr. Nirupama Kasturi
20 Jul 2021 14 min read

Pterygium: A Review

Introduction A pterygium is a fibrovascular, wing-shaped encroachment of the conjunctiva onto the cornea, usually in the horizontal meridian of the palpebral fissure. Histopathology shows hyaline degeneration with elastotic proliferation. Risk factors Exposure to ultraviolet light and environmental microtrauma to the ocular surface is thought to predispose to pterygium formation. A localized limbal stem cell dysfunction, possibly related to ultraviolet induced damage and a genetic predisposition has also been postulated. Pathogenesis Pterygium pathogenesis can be considered as occurring in two stages: the initial disruption of the limbal corneal-conjunctival epithelial barrier, and the progressive “conjunctivalization” of the cornea characterized by cellular proliferation, inflammation, connective tissue remodeling, and angiogenesis Morphology Head—the part which rests on the cornea Neck— constricted portion seen at the limbus Body – remaining bulk of mass Cap—a semilunar infiltrating

Dr. Ramya Subramaniam, DNB · Dr. Srinivas K Rao, DO DNB FRCSEd
20 Jul 2021 15 min read

Keratoconus

Introduction: Keratoconus is a degenerative non-inflammatory disease of the cornea. It presents generally at puberty with progressive corneal steepening & thinning, most typically inferior to the center of the cornea. Keratoconus is characterized by progressive Myopia, both regular and irregular astigmatism in mild cases and vision compromising ectasia in advanced disease. It is usually bilateral and asymmetrical. The incidence of keratoconus is 1 in 2000. Patients often present with complaints of distorted, blurred vision, glare, light sensitivity and history of frequent change of glasses. PATHOGENESIS: Despite extensive research the etiology and exact pathogenesis of keratoconus is still not clearly established. It has been associated with atopic disease and chronic eye rubbing like in patients with Down’s Syndrome & Atopic dermatitis. There has been a possibility of genetic and hereditary disposition. It has been associated with systemic diseases like the Ehler-Danlos syndrome, oste

Dr. Sujatha Mohan
20 Jul 2021 9 min read

Zotero: A Quick Start Guide

Tracking, collecting, organizing, reading, and assimilating the relevant references is an integral process of any scientific research. But this process is laborious when done manually. Hence was the development of reference management softwares (Zotero, Mendeley, EndNote, etc.) for the digitalization of relevant scholarly materials and facilitating the process of managing references. Reference managers provide an efficient way to the scientific authors (a) to track, collect and organize several reference materials. They also provide (b) virtual library with unlimited storage for reference materials with backup, (c) aid in easy management of the process of citation and automatic insertion of a reference/bibliography list in the required formatting style as well as (d) to create and collaborate with multiple libraries/groups. This particular chapter is prepared to give you an overview of the specific features and a quick start guide to use a popular reference manager ‘The Zotero’. What i

Najiya Sundus K. Meethal · Deepmala Mazumdar
19 Jul 2021 14 min read

Techniques of nuclear delivery in Manual small incision cataract surgery

Manual small incision cataract surgery (MSICS) is now practiced in both developed and developing countries. It involves the extraction of a complete or divided nucleus from the capsular bag through the capsular opening and then through the sclero-corneal tunnel. A number of techniques of nuclear delivery have evolved over the time. These techniques have their own merits and demerits. However they give similar results in the hands of experienced surgeons. The methods are broadly classified as follows: Anterior chamber maintainer technique Microvectis technique Phacofracture technique Phacosandwich technique Fish hook technique Ruit's technique We shall now discuss the difference in steps involved in the various techniques. 1. Anterior Chamber Maintainer technique ( Blumenthal`s technique): Fixing the AC Maintainer (Anterior Chamber Maintainer) After the tunnel has been dissected with a crescent knife, two side ports are made with 19 or 20 G MVR knife, one for capsulotomy and the other f

Dr. Ruchi Goel · Dr. KPS Malik
8 Jul 2021 33 min read

Anterior Segment Optical Coherence Tomography in Diseases Of The Ocular Surface And Cornea

I. Introduction : Anterior segment optical coherence tomography (ASOCT) is a sophisticated non-contact imaging device that produces high-resolution images for detailed assessment of the structures of the ocular surface and anterior chamber in various disease conditions. Starting from the earlier generation time-domain devices first described in 1991 by Huang et al [1] to the current Fourier-domain OCT devices, the technological advancement in this device has improved the diagnostic ability tremendously. This imaging modality has evolved into a highly precise tool for clinical diagnosis and management as well as in research and understanding disease pathology. In this review, we describe the evolution of ASOCT, its technology in brief and focus on highlighting the various clinical applications with examples. While Izzat et al first introduced the use of AS-OCT for imaging the anterior segment of the eye [2], it is well known that the OCT initially evolved as a tool for retinal imaging.

Dr. Supriya Sharma · Dr. Somasheila Murthy