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#Made Easy

39 articles

Articles 2 Apr 2021 10 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

Parag K. Shah, DNB · Dr. Varsha V. Prabhu · +1 other
Interesting Reads 2 Apr 2021 26 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
Articles 2 Apr 2021 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

Dr. Jitendra Jethani, MS, DO, DNB, FNB
Interesting Reads 2 Apr 2021 13 min read

Beginners Guide for Performing Vitrectomy

Know your cutter and machine. Current generation vitrectomy cutters work by guillotine mechanism where vacuum holds the Vitreous fibers and presents it to guillotine blade that severs it in one swift motion without exerting significant on fibers. The cutting process needs a fine balance between the speed of cutting and the “pull” created by the vacuum. Higher cutting rates like 10000 cpm allow the surgeon to use a higher vacuum in the range of 600 mm Hg. The rate of vitreous removal also depends on duty cycle and bore size of lumen. Surgeons should test the efficiency of cutters either on cotton fibers or on the vitreous prolapsing out of sclerotomies. One has to learn to recognize when the cutter is pulling without cutting – the most dangerous situation. The surgeon should also familiarize himself with different functions of vitrectomy systems like air injection, Endodiathermy, venturi or peristaltic pumps, light source/s, Phaco Fragmatome, and Viscous fluid injection. It also helps t

Dr. Deependra V Singh
Articles 2 Apr 2021 9 min read

A Beginners Guide to Ophthalmic Surgical Microscope

An operating surgical microscope is the most important optical instrument in the modern era of ophthalmic surgeries. It provides the surgeon with a magnified and illuminated high-quality image of the small ophthalmic structures. Being binocular the surgical microscopes gives the additional benefit of high-quality stereoscopy. History The first German doctor to use a stereomicroscope was Dr. Hans Hinselmann (1884-1959), Prof. of Gynaecology under Dr. Otto von Franque at the University Clinic, Bonn, who adapted in 1925 a Leitz stereomicroscope with coaxial illumination to a movable floor stand. He named IT “colposcope” and used it to visualize the female genital organs particularly for cancer of the cervix. Dr. Hans Littmann (1908 – 1991), head of Med-Lab at Zeiss OptonOberkochen, West Germany (now Carl Zeiss A.G.) and his team of technicians designed in 1953 their first ophthalmic operating microscope Prerequisites for an ideal operating microscope Must have stereoscopic visualization.

Dr. Rohit Rao · Dr. Tamonash Basu
Students Gallery 2 Apr 2021 8 min read

Documentation & Drawing in Ophthalmology

Anterior segment finding Documentations From the days of Hippocrates documentation has been a cornerstone of clinical science. But somewhere down the line this has become a lost art rarely ever practiced by many of us. We tend to ignore or to say correctly run away from it under many pretexts like its time consuming, it’s of no use, etc. And surprisingly this resistance to document is prevalent not only among juniors but spans across the whole spectrum of practitioners. So at times we really ponder is documentation really necessary? The answer is an emphatic yes – the reasons being It’s a standard clinical practice worldwide Follow up is possible only if you can compare it with your previous records. Will help you medico legally Last but not the least unless you are documenting it you have not probably seen it correctly(you think you have seen it all but the moment you come to draw it you find that you don’t remember where the break was it at 1 o’clock or 3 o’clock position and so on).

Dr. Parthopratim Dutta Majumder
Articles 1 Apr 2021 10 min read

Cornea Edema : Ready Reckoner for the Post Graduates

Corneal edema is defined as the increase in the thickness of cornea due to the accumulation of extracellular fluid in epithelium and stroma resulting in loss of corneal transparency. Pathophysiology: Cornea remains in a relatively dehydrated state maintaining a 78% hydration level. Corneal hydration depends on 5 factors. 1. Stromal swelling pressure (SP) This is the tendency of stroma to swell due to interfibrillary proteoglycans and other proteins. The normal stromal pressure is 55mmHg. Imbibition pressure (IP) – It is a negative pressure exerted by glycosaminoglycans by which fluid is drawn into the cornea. Intraocular pressure (IOP) = SP + IP 2. Barrier function The epithelium (Zonula occludens tight junction) offers twice the resistance to water flow compared to the endothelium (macula occludens tight junction) and the electrolyte resistance is 200 times higher in the epithelium than endothelium.1 3. Endothelial pump The endothelium pump function ensures, through active transport,

Dr. Sumana Chatterjee
Articles 1 Apr 2021 7 min read

Refraction Simplified for the Post Graduates

The optics of the eye normally creates a clear image by refracting rays of light to focus on the retina. Imperfections in this optical system create aberrations and thus blurred images. The goal is to analyze them and devise a means to eliminate them. Lower order aberrations are primarily refractive errors when parallel rays of light after refracting, do not focus on the retina with accommodation at rest. 1. Retinoscopy It is the objective method of detecting refractive errors by a method of neutralization. Point focus formed at a far point of the eye according to its refractive status. For e.g. In a patient with 1 dioptre of myopia, the far point is at 1 meter. For easy mathematical calculations, 1metre is used for retinoscopy. But practically, 66cm is preferred as it is easier to perform retinoscopy at an arm’s length (which is 66cm). The two principal meridia are recognized and power is determined by neutralization. Usually the two meridia are 90 degrees and 180 deg. In cases of obl

Dr. R Krishna Prasad · Dr. Sayali D Mahajan
Articles 1 Apr 2021 13 min read

Duanes Retraction Syndrome Made Ridiculously Simple

Synonyms: Stilling–Turk–Duane syndrome. Duane Retraction Syndrome is a type of congenital cranial dysinnervation which occurs in 1-4% of strabismus cases. It has varied presentation mostly involving variable horizontal duction deficits, with narrowing of the palpebral fissure and globe retraction on attempted adduction, occasionally accompanied by upshoot or down shoots Etiopathogenesis Various theories have been proposed earlier for the cause of DRS but currently, the most accepted theory is that of innervational anomalies which leads to all the features of DRS. It is considered to be a part of congenital cranial dysinnervation syndrome as it’s a developmental anomaly of the 6th cranial nerve or its nucleus leading to innervational deficiency of lateral rectus muscle which might be associated with secondary innervational abnormality with Medial rectus. The lack of normal innervations of lateral rectus was proved by electromyographic studies. It is also associated with paradoxical inne

Dr. Prerana Tripathi, DO, DNB, FICO · Dr. Sowmya R, MS,FMRF, FAICO

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