1. Articles 17 min read

   Primary Intraocular Lymphoma

   Introduction Intraocular lymphoma, a great non-infective masquerader occurs intraocularly in either the vitreoretinal( primary vitreoretinal lymphoma PVRL)) or in the uveal space( primary choroidal, iris lymphoma). By definition, PVRL denotes the presence of pathology limited to vitreoretinal space without its occurrence in the central nervous system. The term ‘primary’ is however controversial as almost 56-90% of PVRL patients will ultimately go on to involve the CNS over few months to years( 8-29 months) and is considered a subset of primary CNS lymphoma( PCNSL) [1]. Incidentally, 25% of patients with PCNSL will have concurrent ocular involvement at presentation [2]. Primary choroidal and iridial lymphomas are rarer, less aggressive as compared to their vitreoretinal counterpart and due to their rarity, the following section will deal primarily with PVRL. Pathophysiology of Primary Vitreoretinal Lymphoma The origin of lymphoma cells in the retina is a point of debate. Two etiologies

   Dr. Bikramjit Pal
2. Articles 20 min read

   Corneal Topography

   WHAT IS CORNEAL TOPOGRAPHY? Corneal topography is the study of the shape of the corneal surface. Traditionally, such measurements were limited to the near-spherical central portion of the anterior corneal surface. With the advent of corneal refractive procedures, the necessity to study the more peripheral parts of the cornea and to understand better the optics of both the anterior and posterior corneal surfaces has spawned a number of new devices that allow the clinician to better understand corneal shape, power, and optical performance. EVOLUTION OF CORNEAL TOPOGRAPHY KERATOSCOPY: It is the evaluation of the corneal surface using circular mires reflected from its surface. The earliest device designed to perform this function was the PLACIDO’S DISC, developed by Antonio Placido. It consists of equally spaced alternating black and white rings with a hole in the centre to observe the patient’s cornea. The central opening houses a convex lens for magnification and to aid the examiner’s ac

   RS Dr. Srinivas K Rao · Dr. Ramya Subramaniam
3. Articles 10 min read

   Lattice degeneration of the retina

   Lattice degeneration is a vitreoretinal degenerative process of the peripheral retina with visible lesions that predispose to retinal tears and detachment. Vitreous traction at sites of significant vitreoretinal adhesion is responsible for most retinal breaks that lead to retinal detachment. GOALS of identifying the patients with risk of RD are: Identify patients at risk of RRD Examine patients with symptoms of acute PVD to detect and treat significant retinal breaks Manage patients at high risk of developing retinal detachment Educate high-risk patients about symptoms of PVD, retinal breaks, and retinal detachments and about the need for periodic follow-up. Natural history of precursors to rhegmatogenous retinal detachment Precursors to retinal detachments are PVD, symptomatic retinal breaks, asymptomatic retinal breaks, lattice degeneration, and cystic and zonular traction retinal tufts. Because spontaneous reattachment is exceedingly rare, nearly all patients with asymptomatic RRD w

   MK Dr. Manoj Khatri
4. Articles 9 min read

   Persistent Fetal Vasculature Syndrome

   It is a congenital ocular disorder where fetal vasculature persists. It can be either subtle (no disturbance in vision) or severe (profound visual loss) Anatomy The fetal vasculature is composed of two parts: Tunica vasculosa lentis: It is situated anteriorly encircling the lens. It has anterior and posterior divisions. Anteri­or division has additional attachments to the pupillary frill of the iris. Posterior division has additional attachments to the cil­iary process and continues with the hyaloid artery posteriorly. Hyaloid artery: It is situated porteriorly behind the lens. It is also called primary vitreous. The hyaloid vessel extends from posterior surface of lens to the disc. The vasculature fills the vitreous cavity & has many attachments to the retinal surface Normal regression of embryonic vascular system1 During development blood flow to the eye is through hyaloid artery. At the 240-mm stage (seventh month), blood flow in the hyaloid artery ceases. Hyaloid vascular regressio

   Parag K. Shah, DNB
5. Articles 11 min read

   Retinopathy of Prematurity

   Introduction Retinopathy of Prematurity (ROP) is a fibrovascular proliferative disorder, which affects the developing peripheral retinal vasculature of premature infants. It is an avoidable cause of blindness in children. The initial signs of ROP are detectable by a few weeks after birth, and the condition progresses rapidly thereafter. This means that screening has to be timely, and there is only a very narrow window of opportunity for treating. If not treated, the condition progresses rapidly to Stage 4 or 5 in approximately 50% of babies. The visual prognosis for babies with Stage 5 disease (total retinal detachment) is very poor, even after complex vitreoretinal surgery. The primary goal of screening is to detect all babies with treatable disease in time for treatment to be effective. Pathogenesis In the normal foetus, vascular development of the retina occurs in two phases. Phase 1 (True vasculogenesis): It occurs from 8-21 weeks of foetal development. Spindle cells (mesenchymal p

   Parag K. Shah, DNB
6. Articles 8 min read

   Pan Retinal Photocoagulation (PRP), Focal Laser & Photodynamic Therapy (PDT) Technique & Tips.

   Introduction ‘LASER’ is acronym for “Light Amplification by Stimulated Emission Radiation.” This describes the emission process by which an intense beam of electromagnetic radiation is generated Basic Properties of Laser Always monochromatic (one wavelength) Collimated (all photons run parallel) & focused to a small point Coherent (always in same phase) Highest possible speed Physics Certain substances have property to lase i.e, absorb energy in one form & emit a new form of energy. On pumping these lasing substances electrons are transfered from a lower orbit to higher orbit (Bohr’s theory) Excited atoms in turn decay back to their original orbit of lower energy, emitting photons (packets of energy) This emission can be spontaneous or induced (stimulated) Photocoagulation (PHC) Photothermal reaction Temperature elevation 10 to 20 deg C Protein denaturation Pigment dependent Argon, krypton dye, diode, frequency double Nd Yag Tissue effects Induces moderate sterile inflammation- Creates

   VP RM Parag K. Shah, DNB · Dr. Varsha V. Prabhu · +1 other
7. Anatomy of eye 12 min read

   Anatomy of Conjunctiva

   Conjunctiva is a fine, translucent mucous membrane that joins and covers the anterior surface of eyeball and posterior side of the eyelids. It covers the posterior surface of the lids and reflects to cover the anterior part of the sclera, then becomes continuous with the corneal epithelium. At the lid margin conjunctiva is continuous with the skin. The name “conjunctiva” has originated from the term “conjoin” which means “to join” Parts of the conjunctiva: Broadly conjunctiva is divided into palpebral conjunctiva, fornices, and bulbar conjunctiva. Palpebral conjunctiva: It is the part of the conjunctiva that lines the undersurface or posterior surface of the eyelid. Latin word palpebrae mean “an eyelid” The palpebral conjunctiva is again subdivided into marginal conjunctiva, tarsal conjunctiva, and orbital conjunctiva. The marginal conjunctiva is a transitional zone between the skin of the eyelid and the conjunctiva proper. It starts from the intermarginal strips of the eyelid as a con

   Dr. Parthopratim Dutta Majumder
8. Interesting Reads 21 min read

   A Practical Guide to Data Analysis

   One of the important components of your thesis is analyzing your data. This can range from a few percentages as in a small descriptive study to a more detailed analysis. While collecting data for your thesis it is important to give some thought to what the important parameters that you would want to study are. Make sure that you collect adequate information about these parameters and that you enter the information in a way that it can be analyzed. Doing basic analysis using MS Excel and a few online resources is not difficult for anyone who is a little familiar with using a computer. You do not have to be an expert to do this. This chapter aims to guide you through the steps of identifying the type of data you are working with, guiding you through different common statistical techniques on MS Excel and introducing you to a few online resources. With these basic skills, you will be able to do most of your data analysis on your own. Now that you have finished entering your data completel

   Dr. Ronnie George
9. Interesting Reads 4 min read

   Ten Tips and Tricks to Examine a child in Your Practice

   1. Choosing the best time: Train your clinic receptionist to ask the parents when the child is likely to be cooperative and/or awake. It is not uncommon for infants to sleep a lot during the day. It is also not uncommon for children on anti-seizure medication to be sleepy, thereby making examination difficult. 2. Child-friendly atmosphere: Train your staff to speak to the child and address the child by name and smile and make the family feel welcome. The décor in the waiting area and in the examination room should be colorful with pictures and cut outs appropriate for a child. Furniture chosen should be non-impact and the flooring safe for children, if they fall. It should also be easy to maintain by wiping down frequently to prevent spread of infection. Using many colorful toys during examination takes away the fear of the experience to some extent for the child. 3.White coats: A child often associates white coats with doctors and hospitals. Hence it is best to avoid wearing one. If c

   Dr. Meenakshi Swaminathan
10. Articles 10 min read

    Diplopia and Hess Charting

    Diplopia Charting Diplopia chart is the record of separation of the diplopic or double images in the nine positions of gaze. It can be plotted charted in patients who cooperate and can appreciate the double vision and with incomitant or comitant deviation. The method The patient should be comfortable with his head erect and should preferably be still throughout the examination. The test is preferably carried out in a dark room. Red glass is put in front of one of the eyes (red in front of right, R for R, is a convention). It is desirable to use Armstrong goggles since these are shaped to fit the orbital margin and therefore patient would be looking only through the colored medium. The examiner holds the torch (vertical source of light) at around ½ m or 1 m (It is important to mention the distance on the chart). This source of light could be horizontal if the complaint is of vertical separation of images The light is held directly in front of the patient at first. If the patient sees a

    F Dr. Jitendra Jethani · FNB

More articles