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PARS PLANA VITRECTOMY, RIGHT EYE a Case Study on the Operating

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PARS PLANA VITRECTOMY, RIGHT EYE a Case Study on the Operating PARS PLANA VITRECTOMY, RIGHT EYE A Case Study on the Operating Room Presented to The Faculty of School of Nursing University of Baguio In Partial fulfillment of the Requirement for the Subject NCENL06 SUBMITTED TO: Larry Michelle Pascual, RN Clinical Instructor SUBMITTED BY: Arlene Esilen Carreon September 2012 1 ACKNOWLEDGMENT I owe my deepest gratitude to the following for the making of this case possible: First and foremost to our Creator, as source of our life and being, and for reasons too numerous to mention; To the University of Baguio, for being true to its mission and vision of empowering its students, giving us the chance to develop our skills through experience; To the Dean, Ms. Jocelyn Apalla, Department Head, Ms. Helen Alalag, and BSN IV Coordinator, Ms. Minda Bahug for making hospital exposure feasible; To my clinical instructor, Mr. Larry Michelle Pascual, who’s intellectual, clinical and practical insights and guidance made our hospital duty experience appreciated and valued in all dimensions; To my parents, for their unending love and support, and for molding me to become the person that I am right now, for the encouragement and words of wisdom they have inculcated in my mind, and the lessons they have taught that help me go on in this part of my journey in life, my deepest gratitude. 2 TABLE OF CONTENTS Chapter Page Title page........................................... i Acknowledgement...................................... ii Table of Content .................................... iii Chapter I Patient’s Profile............................... 1 a. Biographic Data Chapter II Anatomy and Physiology.............................. 2 a. Structure of the Human Eye Chapter III Pathophysiology...................................... 15 Chapter IV Patient’s Preparation................................ 26 a. Skin preparation b. Position c. Draping d. Anesthesia used Chapter V Discussion of the Procedure.......................... 28 Chapter VI Instrumentation .................................... 30 Chapter VII Drug study.......................................... 34 Bibliography 3 CHAPTER I PATIENT’S PROFILE A. Bibliographical Data NAME: Patient X AGE: 66 years old SEX: Female CIVIL STATUS: Single ADDRESS: 122 New Lucban Extension, Baguio City NATIONALITY: Filipino RELIGION: Roman Catholic CHIEF COMPLAINT: Blurred Vision ADMITTING DIAGNOSIS: Vitreous Hemorrhage, Right eye; Cataract FINAL DIAGNOSIS: Vitreous Hemorrhage, Cataract Right eye secondary to branch retinal vein occlusion OPERATION PERFORMED: Pars Plana Vitrectomy, Right Eye 4 CHAPTER II ANATOMY AND PHYSIOLOGY The anatomy and physiology of the human eye is an important part of body. Any eye problem should be considered an emergency. Above: Schematic diagram of the Structure of the Human Eye. 1. AQUEOUS HUMOUR Located at the front of each eye in the human body. A 5 watery fluid that fills the chamber called the "anterior chamber of the eye" which is located immediately behind the cornea and in front of the lens, and also the "posterior chamber of the eye" which is a very narrow compartment located between the peripheral part of the iris, the suspensory ligament of the lens, and the ciliary processes. The aqueous humour is very slightly alkaline salt solution that includes tiny quantities of sodium and chloride ions. It is continually produced, mainly by the capillaries of the ciliary processes, and drains away into Schlemm's canal, located at the junction of the cornea and 2. CHOROID The layer of the eyeball located between the retina and the sclera. It is a thin, highly vascular (i.e. it contains blood vessels) membrane that is dark brown in colour and contains a pigment that absorbs excess light and so prevents blurred vision (due to too much light on the retina). The choroid is loosely attached to the inner surface of the sclera by the lamina fusa. The side of the choroid closest to the centre of the 6 eyeball is attached to the retina. This transparent innermost layer of the choroid is called Bruch's Membrane. The structure of the choroid itself consists mainly of a dense capillary plexus and of many arterioles and venules transporting blood to and from this plexus. 3. CILIARY MUSCLE Located in each eye in the human body. It is one of three zones of the ciliary body (which connects the choroid with the iris). Contraction and relaxation of the ciliary muscle alters the curvature of the lens. The correct term for the adjustment of the shape of the lens to change the focus of the eye is "accommodation". This process may be described simply as the balance existing at any one time between between two states: Ciliary Muscle relaxed: The suspensory ligaments attached to the ciliary body that hold the lens in place are stretched, causing the lens to be relatively flat. This enables the eye to focus on distant objects. Ciliary Muscle contracted: The tension on the suspensory ligaments attached to the ciliary body is reduced allowing the lens to be relatively round. This enables the eye to focus on close objects (near to the eye). 7 4. CORNEA Transparent circular part of the front of the human eyeball. It has an important optical function as it refracts light entering the eye through the pupil and onto the lens (which then focuses the light onto the retina). The degree of curvature of the cornea varies between individuals and also throughout the life of an individual. It is more prominent in youth than later in life, when it can become flatter in shape. The cornea has a complex structure that specialist texts describe in terms of the following layers (from the outside inwards): 1. Several strata of epithelial cells, continuous with those of the conjunctiva; 2. A thick central fibrous structure called the substantia propria; 3. A homogeneous elastic lamina; 4. A single layer of endothelial cells forming part of the lining membrane of the anterior chamber of the eyeball. The cornea a non-vascular structure (which means that it does not contain any blood vessels) as the capillaries that supply it with nutrients terminate in loops at its circumerfence. It is supplied by many nerves derived from the ciliary nerves. These enter the laminated tissue of the cornea. It is therefore extemely sensitive. 8 5. FOVEA A small depression forming a shallow pit in the retina at the back of each eye in the human body. Because it contains a large number of the light-sensitive photo-detector cells called cones, the fovea is the area of greatest acuity of vision. This means that when an eye is directed at an object, the part of the image of that object formed on the retina that falls onto the fovea is the part of the image that will be perceived in the greatest detail. The fovea is slightly yellow in apperance and so was first called the "Yellow Spot" or "Macula Lutea" of Sömmerring. The existance of such an area is only known to occur in humans, the quadrumana (a group of primates comprising apes and monkeys), and some saurian reptiles. 6. HYALOID MEMBRANE A transparent membrane that encloses the vitreous humour, seperating it from the retina. In front of the ora serrata (the area in which the retina terminates as a jagged margin towards the front of the eyeball as it approaches the ciliary body) the hyaloid membrane is thickened by radial fibres and is called the Zonule of Zinn or (another name for the same thing, the zonula ciliaris). 9 7. IRIS The coloured part of the human eye. That is, the anterior surface of the iris has different colours in different individuals and is also marked by lines that converge toward the pupil. However, the posterior (back) surface of this iris has a deep purple tint due to two layers of pigmented columnar epithelium. This pigmented epithelium is usually referred to as the "pars iridica retinae" but is sometimes called simply "uvea" due to the similarity of its colour to that of a ripe purple grape. It is a thin circular contractile curtain located in the aqueous humour - in front of the lens but behind the cornea. It contains a circular aperture (or "hole") called the pupil and located just to the nasal side of the centre of the iris. A simple description of the iris is that it is a coloured diaphragm of variable size whose function is to adjust the size of the pupil to regulate the amount of light admitted into the eye. It does this via the pupillary reflex (which is also known as the "light reflex"). That is, when bright light reaches the retina, nerves of the parasympathetic nervous system are stimulated, a ring of muscle around the margin of the iris contracts, the size of the pupil is reduced, hence less light is able to enter the eye. Conversely, in dim lighting conditions the pupil opens due to stimulation of the sympathetic nervous system that contracts of radiating muscles, hence increases the size of 10 the pupil. The iris is composed of a series of layers, including: (1.) Flattened endothelial cells on a hyaline basement- membrane; (2.) Stroma - consisting of fibres and cells; (3.) Muscular Fibre - consisting of circular and radiating fibres; (4.) Pigment - the location of pigment cells differing in different irides; (5.) Arteries of the iris, and (6.) Nerves of the Choroid and Iris. 8. LENS An important part of the structure of the eye. This lens is a transparent structure enclosed in a thin transparent capsule. It is located behind the pupil of the eye and encircled by the ciliary processes - that slightly overlap its edges. The lens of the eye helps to refract light travelling through the eye (which first refracted by the cornea). The lens focuses light into an image on the retina. It is able to do this because the shape of the lens is changed according to the distance from the eye of the object(s) the person is looking at.
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