Visual Optics and Assessment

OPTOMETRY · SEMESTER 2 Clinical Optometric Procedures: Patient Profile And Case History Visual Optics and Assessment START READING NOTES Contents of This Topic Clinical Optometric Procedures: Patient Profile And Case History  Hobbies/Lifestyle Surname D.O.B.: Gender: Figure 2.1 Communication  Ametropia/Presbyopia R Right L Left Occ. Ointment Gutt. Drops Chapter 3-1(Additional) INTRODUCTION FACE / HEAD July 2010, Version 1 1 – 2 Figure 1 ORBIT/RIM ADNEXAE Functional Assessment July 2010, Version 1 1 – 4 July 2010, Version 1 1 – 5 July 2010, Version 1 1 – 6 THYROID ASSESSMENT July 2010, Version 1 1 – 7 CORNEA Cotton Wisp Method July 2010, Version 1 1 – 8 Anterior Chamber Depth Figure 3 July 2010, Version 1 1 – 9 Clinical Optometric Procedures: Patient Profile And Case History CHAPTER 2 – PATIENT PROFILE AND CASE HISTORY This chapter will include a review of: Patient profile Case history PATIENT PROFILE A patient’s profile is essential in every eye exam. It involves the extraction of information on the demographics of the patient and their profile in terms of his or her family life, education, marital status, etc. It has been suggested that a patient profile will allow the practitioner to be effective in providing patient care if he or she has knowledge of the patient’s profile. The demographic information extracted facilitates future communication with the patient. In addition, the significance of the information gathered in this part of the examination is linked in large part to susceptibility to normal or abnormal conditions of vision or ocular health. For example, a patient who is approximately 50 years of age is likely to complain of near vision problems due to age related changes in focusing ability at a near distance (presbyopia). In the broader sense, information elicited also informs the practitioner’s differential diagnosis or formulation of a tentative diagnosis. Information extracted includes the following aspects: Name of patient Address Contact details Age Occupation Race/ethnicity Gender  Hobbies/Lifestyle Education level These aspects are the first that are recorded in the patient record card (Table 2.1) Table 2.1 Patient profile aspect of the record card (Adapted from Clinical Procedures in Primary Eyecare Care: DB Elliot) EYE EXAMINATION RECORD CARD PX ID First name: Age Date: Surname D.O.B.: Gender: Address: Contact number: Occupation: Hobbies: Race: International Centre for Eyecare Education CASE HISTORY The Case History comprises a numerous aspects, viz. 1. Communication 2. The Chief Complaint 3. Patient’s Ocular History 4. Patient’s Ocular Health 5. Medications 6. Allergies 7. Family Ocular and Medical History 8. Vocational And Avocational visual Requirement Introduction Generally, case histories are taken at the beginning of a consultation. However, with experience the eyecare practitioner will notice that history taking continues throughout the examination as more information arises from conversations, occurring during the course of the examination. A case history should be taken in an appropriate location so that the patient is free to provide as much information as they can without any apprehension and respectful to the patient’s privacy. Ideally the practitioner should be facing the patient and should be positioned at about the same level. Room lights should be on fully. These simple guidelines will allow the patient to be more comfortable with the eyecare practitioner and establishes a good rapport with the patient. Main Objectives of a Case History 1. To elicit reasons for visit 2. To ascertain patient’s expectations 3. To acquire relevant background information 4. To determine the specific tests or procedures that should be performed during the examination 5. To form a tentative diagnosis 1. Communication Figure 2.1 Communication Greet the patient with confidence. Introduce yourself. Be professional Establish a relationship of trust Show genuine interest Be courteous and respectful Ask open-ended questions. For example, an open ended question would be: “what difficulties are you experiencing with your vision?” while a closed-ended question would be: “can you see clearly at distance?” Open-ended questions (open probing) are more likely to elicit useful information, e.g. ‘How does your eye feel?’, rather than ‘Does your eye feel painful? If necessary, list symptoms or conditions to elicit specific information. Generally, asking questions which can be answered by a simple ‘yes’ or ‘no’ (closed probing) should be avoided, unless such a response is all that is sought. To ensure that a comprehensive case history is obtained, questions should be asked in a logical sequence. Repetitive or redundant questions avoided. Questions should be asked in a clear and concise manner. The use of jargon and technical terms must be avoided under all circumstances. Either a standard form or a structured approach can be employed. There are six elements that are essential in a case history. They include: The chief complaint, patient’s medical history, visual and ocular history, medication and allergy history, family ocular and medical history and vocational and avocational visual requirements. 2. The Chief Complaint The chief complaint is usually the primary reason for the patient seeking consultation. The patient’s chief complaint may be a symptom that is concerning them. One may be able to elicit the chief complaint by asking: “What is the reason for your visit?’’ “What brings you to the practice today?’’ “What seems to be the problem?’’ How to explore the Chief Complaint? Once the chief complaint(s) has/have been elicited, more details must be elicited from the patient. Depending on the complaint the following questions will help gather detailed information. For example, if the patient comes in complaining of a HEADACHE, the information gathered about headache would cover the following aspects which can be remembered by using the pneumonic DR. FALLOPPES. The pneumonic is elaborated as follows: Description of the complaint/symptoms: What is the main complaint? Duration: How long does it last? Sometimes symptoms can present themselves for short periods of time due to their association with other systemic conditions. For example, migraine sufferers would usually experience a visual aura that lasts for approximately 20 minutes before the headache presents itself Relief or remitting factors: What relieves it? Both of these factors would contribute to one establishing

OPTOMETRY · SEMESTER 2 Clinical Optometric Procedures: Infection Control Visual Optics and Assessment START READING NOTES Contents of This Topic Clinical Optometric Procedures: Infection Control INTRODUCTION HYGIENE CARE OF SOLUTIONS AND PHARMACEUTICAL AGENTS DISINFECTION PROTECTION BIOHAZARDS HIV/AIDS AND INFECTION CONTROL Clinical Optometric Procedures: Infection Control CHAPTER 1 – INFECTION CONTROL This chapter will include a review of: Hygiene Care of solutions and pharmaceutical agents Disinfection Protection Biohazards HIV/AIDS and infection control INTRODUCTION Infection Control is an absolutely essential component of the practice of primary eyecare. Given the risks of being exposed to infectious organisms, it is recommended that all patients be treated as potentially infected individuals. The clinician must be knowledgeable & remain vigilant about proper hygienic procedures for routine and specialized eye care. While the optometric environment has been rarely noted to involve invasive procedures, there are numerous optometric procedures that involve contact with mucous membranes and this very frequently is the area of contact with pathogenic organisms. There are several guidelines that the eye care practitioner should follow in order to minimize the risk of cross infection, that is, from ensure that the practitioner does not transfer infection to the patient or vice versa. HYGIENE Hygiene begins with very simple and basic steps. Hand washing, the most essential personal procedure, must become a reflex and should be performed before, during and after patient examinations. Hand Washing Figure 1.1 provides a diagrammatic representation of the process of hand washing. In cases where there are no levers to close the water supply, the clinician should use a clean tissue to close the tap and discard the tissue thereafter. International Centre for Eyecare Education Figure 1.1 Hand washing procedure Suitable hand washing agents listed from the most effective antimicrobial activity includes alcohol preparations, chlorhexidine, iodophors and plain soap. Newer developments in maintaining hand hygiene include alcoholbased hand gels which can be very effective in situations where adequate hand washing facilities are unavailable. Cleaning of Surfaces Surfaces such as tabletops need to be cleaned with commercial solvents or solutions to remove dust, dirt, oils or other accumulations that may harbor organisms (Fig.1.2). Instruments should be constantly cleaned. Areas of dermal contacts (e.g. phoropters, slit lamp, headrests, etc.) must be wiped with alcohol swabs after examination of each patient. Figure 1.2 Cleaning of surfaces International Centre for Eyecare Education CARE OF SOLUTIONS AND PHARMACEUTICAL AGENTS Expiration Dates of Solutions Dates on solution and medication bottles should be respected and bottles that are outdated or opened for more than 1 month should be discarded (Fig.1.3). It is advisable to record the opening date on the bottle. Figure 1.3. On expiry, medication/solution should be discarded if seal packed and open bottles should be discarded as per the clinician’s suggestion or should be used for a month only Contamination of Bottles Contamination of bottles should be avoided not to spread organisms from one patient to another. Bottle tips should not come in contact with eyes or dermal areas (Fig. 1.4). Bottle caps must not be placed on surfaces but rather remain in the practitioner’s hand until the bottle is recapped after instillation of drugs. Figure 1.4 Contact from the nozzle of the bottle should be avoided to prevent contamination DISINFECTION Disinfection involves the treatment of surfaces or medical devices by an agent to destroy infectious organisms. Tonometer tips, gonioscopes and other eye contact devices should be washed with soap and water after use then soaked for 10 minutes in a disinfecting agent. The recommended agent is 1-part house bleach to 100 parts distilled water solution. Hydrogen peroxide (3%) can also be used instead of bleach solution but it is more costly. Following disinfection, rinse with sterile saline and air dry. Unused bleach: water solution is good for two weeks. The solution used in vials for the disinfection process of instruments must be changed daily. The vials must also be washed with soap and water. Extending soaking beyond 10 minutes can damage the instruments and is not recommended. An alcohol swab can also be used to wipe the eye contact devices in the presence of low infection risks and if (for some reason) the above steps cannot be performed. Treating every patient as potentially infectious, however, the bleach/water or peroxide methods should be respected as much as possible. Contact lenses should be washed, rinsed, disinfected & stored appropriately after each trial using an approved method. Usually contact lenses are cleaned with contact lenses specific cleaning agent, rinsed with saline and disinfected in 3% hydrogen peroxide. The peroxide is then neutralized appropriately and the lenses are stored in multi-purpose solution. Alternatively, contact lenses can be cleaned with a cleaning agent, rinsed and disinfected in a contact lens autoclave in sterile non-preserved saline. Surgical instruments should be ideally heat-sterilized by autoclave or by ethylene oxide gas sterilization and sterile wrapped for storage. An alternative, more “office-based” approach is to wash the instruments with soap and water (using cleaning brushes) and store them in a stainless steel tray with appropriate commercial storage solutions (eg. Benzalkonium Chloride). The solution needs to be changed weekly. To dry store, the instruments are rinsed with saline and air-dried. Before use, they are again cleaned, disinfected with the solution and rinsed with saline. PROTECTION Latex gloves should be worn whenever there is a risk of contact with body fluids or tissues, especially in the presence of a skin break on the patient or you (Fig.1.5). Always wash hands before and after glove use. Eye protection, masks and gowns should also be remembered and used in instances when there may exist the possibility of liquid or tissue splashes. Figure 1.5 Wearing latex gloves decrease chances of exchange of body fluids between the patient and clinician incase of any skin break BIOHAZARDS Waste products (tissues, cotton tip applicators, etc.) should never be left around to be picked up and disposed later. Wastes should always be disposed immediately in the proper wastebaskets with a garbage bag. Blood & tissue products must be separated and disposed in specially

OPTOMETRY · SEMESTER 2 Clinical Optometric Procedures – Introduction Visual Optics and Assessment START READING NOTES Contents of This Topic CLINICAL OPTOMETRIC PROCEDURES MODULE CLINICAL OPTOMETRIC PROCEDURES MODULE INTRODUCTION TO THE OPTOMETRIC EXAMINATION The optometric examination or refraction is aimed at detecting ocular abnormalities and determining functional corrections for eye defects. The examination must be carried out thoroughly in relation to the specific needs of the patient. In addition to the detection, the practitioner must suggest or provide remedial visual training where necessary and provide advice to the patient on aspects of visual efficiency. The comprehensive eye examination comprises a battery of tests and investigations to elicit the information in order to determine the patient’s needs, provide a diagnosis and offer remediation (if possible) for the problems reported. In addition to performing the tests, equally essential is the recording of information which in most cases is a legal requirement to safeguard both the patient and the practitioner. Ultimately the practitioner must exercise his or her professional judgment in determining which tests are relevant to the specific patient examination given the patient complaints. However, he or she must not lose sight of the tests which are mandatory in order to make a diagnosis regarding the various aspects that are investigated in refraction. These include an assessment of the motor, refractive and sensory systems and an assessment of the ocular health of the patient. List of tests that investigate these various aspects are listed in Appendix 1 at this end of this module. Four Key Areas of the Optometric Examination A: Preliminary Examination B: Visual function assessment C: Ocular health examination D: Management plan Each of these key areas has numerous investigations or procedures which make up the comprehensive optometric examination. The procedures follow a sequential pattern from the eliciting of patient complaints, investigation of tentative diagnoses through a series of problem and patient appropriate tests of eye health, refraction and binocular vision. The formulation of an appropriate management plan is the end result of the assessment process. This approach is sometimes referred to as the “problem-oriented” optometric examination. Procedures Incorporated in the Key Areas of Optometric Examination A: Preliminary examination Patient profile and case history Visual acuity Near point of convergence Cover test Motilities and saccades Pupil reflexes Confrontation fields Interpupillary distance measurement Colour vision testing International Centre for Eyecare Education B: Visual function assessment Objective refraction: retinoscopy, autorefraction, keratometry Subjective refraction Corrected visual acuity Measurement of horizontal and vertical phorias Fusional vergences Fixation disparity Accommodation testing Stereoacuity C: Ocular health assessment Fundus examination under non-dilated and dilated conditions Slit-lamp biomicroscopy Other tests as indicated D: Management plan Clinical decision making is an integral part of the management plan. It requires a practitioner’s ability for “clinical judgment, inference and diagnostic reasoning”. The deductive clinical reasoning behind patient care can be systematically managed by employing the “SOAP” format. This acronym stands for Subjective, Objective, Analysis and Plans. This basically translated indicates the practitioner would carefully gather the subjective and objective information gathered from the patient assessment, he would develop an assessment and plan and follow-up for each problem identified during the comprehensive optometric assessment. Appendix II has a suggested order for performing various procedures in refraction. This has been adapted from Clinical Procedures in Primary Eye Care by DB Elliot. International Centre for Eyecare Education SECTION A – PRELIMINARY EXAMINATION ← PREVIOUS TOPICNEXT TOPIC →VIEW MODULE NOTESVIEW SEMESTER NOTESALL OPTOMETRY NOTES Need These Notes as PDF? Request a formatted copy for offline study, printing or revision. GET PDF NOTES ON WHATSAPP

OPTOMETRY · SEMESTER 2 Refractive errors Visual Optics and Assessment START READING NOTES Contents of This Topic REFRACTIVE ERRORS Refractive Errors Emmetropia Ametropia Myopia Causes Axial Myopia Curvature Myopia Index myopia Abnormal position of the lens Types Congenital myopia Simple myopia Aetiology Pathological myopia Acquired myopia Symptoms Signs Complications Treatment Optical Treatment Axial Hypermetropia Curvature Hypermetropia Index Hypermetropia Classification Latent Hypermetropia Manifest HypermetropiaMH is made up of two components Clinical Types Simple hypermetropia Pathological hypermetropia The Normal Age Variation Regular astigmatism Refractive types Physiological types Study Reports Presbyopia TreatmentConvex lens Aphakia Optics of Aphakia Disadvantages Aphakic formula Pseudophakia Calculation of IOL power Refractive stages of a Pseudophakic eye Advantages REFRACTIVE ERRORS REFRACTION Refractive Errors Emmetropia Ametropia Emmetropia Emmetropia means no Refractive error It is the ideal condition in which the incident parallel rays come to a perfect focus upon the light sensitive layer of the retina, When accommodation is at rest Ametropia Ametropia means Refractive error Eye It is the opposite condition , where in the parallel rays of light are not focused exactly upon the retina , When the accommodation is at rest Ametropia Myopia Hypermetropia Astigmatism Myopia Principal focus is formed in front of the retina Causes Axial Myopia Curvature Myopia Index Myopia Abnormal position of the lens Axial Myopia Axial myopia results from increase in anteroposterior length of the eye ball. Normal Axial length- 23mm to 24mm 1mm increase in AL – 3Ds of Myopia Curvature Myopia Curvatural myopia occurs due to increased curvature of the cornea and Lens or both. Anterior surface of the cornea +7.8mm Posterior surface of the cornea -6.5mm 1mm increases in radius of curvature results in – 6 Ds of Myopia Index myopia Index myopia results from increase in the refractive index of crystalline lens. Refractive index of normal Lens 1.42 Abnormal position of the lens Positional myopia is produced by anterior displacement of crystalline lens in the eye. Accommodative Myopia:. Myopia due to excessive accommodation. Types Congenital myopia Simple Myopia (or) Developmental myopia Pathological Myopia (or) Degenerative myopia Acquired myopia Congenital myopia Congenital myopia is present since birth however, it is usually diagnosed by the age of 2 – 3 years. Simple myopia Simple or developmental myopia is the commonest variety. It is considered as a physiological error not associated with any disease of the eye. Power limit less than 6D Aetiology Axial type of simple myopia Curvatural type of simple myopia Pathological myopia Myopia associated with degenerative changes in the eye. Myopia more than 6D to25D or More than 25D Aetiology Axial growth (i) Heredity (ii) General growth process Acquired myopia Some of the causes of acquired myopia * Index myopia * Curvatural myopia * Positional myopia * Consecutive myopia * Pseudo myopia * Space myopia * Night myopia (or) Twilight myopia * Drug induced myopia Symptoms Poor vision for distance Asthenopic symptoms Exophoria Muscae volitantes (pathological) Night blindness (pathological) Signs Large eye ball deep Anterior chamber sluggish Pupil Large Disc Complications Retinal tear – Vitreous haemorrhage Retinal detachment Degeneration of the vitreous Primary open angle Glaucoma Posterior cortical cataract Posterior staphyloma Treatment Optical Spectacle Correction (Concave Lens) Contact lens Surgical PRK Keratomileusis Epikeratophakia Redial Keratotomy Optical Treatment Concave lens Myopic with Exophoria give full correction. Myopic with Esophoria give under correction. HypermetropiaPrincipal focus is formed behind the retina Causes Axial Hypermetropia Curvature Hypermetropia Index Hypermetropia Abnormal position of the lens Axial Hypermetropia Axial hypermetropia is by far the commonest In fact, all the new- borns are almost invariably hypermetropic (approx,+2.50D) This is due to shortness of the globe, and is physiological. Normal axial length – 23mm to 24mm 1mm decrease in AL – 3Ds of hypermetropia Curvature Hypermetropia In which the curvature of cornea, Lens or both is flatter than the normal resulting in a decrease in the refractive power of the eye. Anterior surface of the cornea- 7.8mm Posterior surface of the cornea- 6.5mm 1mm increase in radius of curvature results in – 6Ds of hypermetropia Index Hypermetropia Index hypermetropia occurs due to change in refractive index of the lens in old age. It may also occur in diabetics under treatment. Refractive index of Normal Lens – 1.42 Classification Total Hypermetropia may be divided into (a) Latent Hypermetropia (b) Manifest Hypermetropia (i) Facultive Hypermetropia (ii)Absolute Hypermetropia Latent Hypermetropia LH which is corrected physiologically by the tone of ciliary muscle. As a rule latent hypermetropia amounts to only one dioptre. It can be revealed only after atropine cycloplegia. Manifest HypermetropiaMH is made up of two components Facultative hypermetropia is that part of hypermetropia which can be corrected by the effort of accommodation. Absolute hypermetropia which can not be overcome by the effort of accommodation. Clinical Types Simple hypermetropia Pathological hypermetropia Functional hypermetropia Simple hypermetropia It results from normal biological variation in the development of the eye ball. It includes Axial and Curvatural HM. It may be hereditary. Pathological hypermetropia PH results due to either congenital or acquired conditions of the eye ball which are out side the normal biological variations of the development. The Normal Age Variation At birth:- 2D to 3 D Commonly Present At the age of 5 Yrs- 90% of Children’s are Hypermetropic At Puberty:- Emmetropic Symptoms Head ache Blurred vision particular near work Convergent squint Early onset of presbyopia Eye Strain Complications Eye appears to be small including cornea and anterior chamber becomes shallow Extreme cases – Microphthalmos Retinal reflex – Shot silk-Retina Treatment Optical Spectacle ( Convex Lens ) Contact lens Hypermetropic with Exophoria give under correction Hypermetropic with Esophoria give full correction Surgical Thermokeratoplasty Astigmatism Astigmatism is that condition of Refraction where the point focus of light cannot be formed upon the Retina Causes Curvature Ex: Keratoconus, Lenticonus etc.. Centering error Ex: Sub location of the lens Refractive index Ex: Cataract Retinal Oblique placement of macula Types Regular Irregular Regular astigmatism Refractive types Physiological types Refractive types Simple astigmatism Compound astigmatism Mixed astigmatism Physiological types With rule astigmatism Against rule astigmatism Oblique astigmatism Bioblique astigmatism Symptoms Head ache Blurring of vision Eye