Cataract Testing. What a Patient undergoes prior to surgery

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1 Cataract Testing What a Patient undergoes prior to surgery

2 FINANCIAL DISCLOSURE I have no financial interest or relationships to disclose

3 What do most Technicians find to be the most mundane yet very important part on all levels of the eye exam?

4 TAKING HISTORY AND SYMPTOMS/COMPLAINTS

5 1. What are your symptoms and the duration they have been experiencing them? (glare, reading the street signs, dim lighting, etc.) 2. Do you wear glasses or contact lenses? For Contact Lenses you want to know what kind? Last worn? Ever tried monovision? (Contacts can alter the shape of the cornea) 3. Ever had any eye surgeries, injuries, or other ocular conditions? Lasik/PRK/AK/RK alter the shape of the cornea, Scleral Buckles, CME and other conditions can alter the length of the eye 4. Of course the general health, family history and surgical history are also important

6 TESTING TO BE DONE BY THE TECHNICIAN (NOT DONE IN ANY PARTICULAR ORDER)

7 Visions: with and without correction Near acuity if complaining of trouble reading small print or interested in monovision Manual Keratometry (usually verified through automated testing) Refractometry for best acuity (BAT if 20/40 or better or complaining of glare) Confrontation Fields, Pupillary Response, Phorias A-scan (Automated if possible /manual if needed) Topography or Corneal Mapping if needed IOP or intra ocular pressure reading Slit lamp Exam to include Dilated Fundus Exam(done by the Physician)

8 TAKING ACUITY Getting the best possible vision or best corrected vision will help in determining if cataract surgery is warranted or not and if the benefits out weigh the risk. It is important to know the vision without glasses or contacts because the goal of cataract surgery is to improve their vision or quality of life with less dependency upon glasses or contacts and not always aiming for 20/20 in both eyes. Patient s who may want to have monovision correction will need to have their near vision acuity tested as well as which eye is Dominant.

9 KERATOMETRY Measures the curvature of the cornea and helps in diagnosing conditions like Keratoconus, Regular/Irregular Astigmatism (for possible TORIC IOL to correct astigmatism) and other conditions that may affect the outcome of surgery. We also use this as another means to check our measurements against what we get from the automated testing done.

10 MANIFEST REFRACTOMETRY A good refraction tells what the patient s best corrected vision is and sometimes how hindered their vision is with current glasses. We can also check to see if a patient sees double if the power between both eyes is very different. BAT(Brightness Acuity Test) using the best corrected vision to note the affect lighting may have on the patient s vision.

11 AUTO-REFRACTOR Provides automated refraction and can be used as a starting point if a patient forgot their eyeglasses or no records of previous refractions/eyeglass corrections. Can be used as another means to verify closeness of manual refractions. A lot of Auto-refractors provide additional readings such as Keratometry, Corneal Diameter/white to white, pupil size and clarity of the readings to ensure accuracy of the readings.

12 CONFRONTATION FIELDS, PUPILLARY RESPONSE, PHORIAS Helping to determine loss of field of vision, possible neurological or cardiovascular conditions and possible eye movement restrictions that may lead to diplopia or other conditions which may also affect the outcome of surgery. Some patients may have Anisocoria (different size pupils at the same time) which a lot of patient s pick up on more after surgery since they are hopefully seeing much better. Some patients may have had a stroke, Branch Retinal Vein Occlusion, Anterior Ischemic Optic Neuropathy or very advanced Glaucoma which may show up performing these test.

13 A-SCAN ULTRASOUND BIOMETRY Is used to determine the length of the eye, curvature of the cornea, anterior chamber depth, white to white(diameter of the cornea) and some even measure pupil size and other aspects of the eye to help calculate the power of the Intra Ocular Lens (IOL). There are multiple formulas and different lens types that the surgeon can choose from so knowing what your doctor prefers helps when performing the testing.

14 AUTOMATED A-SCAN Most preferred method used when performing an A-scan because nothing touches the eye, provides multiple readings, most provide an accuracy on each scan, more comfortable on the patient and other aspects that make it more desired to be utilized. Most provide multiple Formulas to calculate the IOL powers and are able to be setup according to individual physicians protocols on their choices of lenses

15 Most often done when: MANUAL A-SCAN 1. unable to obtain a reading from the Automated A-scan or inconsistencies between the scans 2. Cataract too dense or Cornea to cloudy to achieve a reading from the automated A-scan 3. Patient unable to focus or adhere to instructions to acquire the scans, or other medical conditions/reasons that constitute using Manual A-scan over Automated A- scans. 4. Most often require manual entry of Keratometry readings from another sourcec

16 SUBMERSION A-SCAN Most often used when the Automated and the Manual A-scans where unable to achieve the results to calculate IOL powers. Not as user friendly as the Automated or the Manual A-scan and not as readily available in most offices or clinics Most only provide the axial length measurements and need to be transferred to another means to do the IOL calculations

17 B-SCANS Often used when unable to view the fundus or the anterior section of the eye due to severe Corneal Haze or very advanced Cataracts

18 Phakic or Normal Lens Pseudophakic or artificial lens Aphakic or no lens at all Displaced or dislocated Lenses DIFFERENT EYE TYPES Silicone Oil filled eyes with any of the above mentioned types of eyes High Myopic (nearsighted) eyes that may require lower powers or some no powers at all High Hyperopic (farsighted) eyes that may require higher powers than usual Presbyopia (mature eyes) Eyes needing multifocal to correct both near and far or monovision

19 DIFFERENT LENS TYPES Types of lenses include one piece or multi piece, Acrylic, Silicone, PMMA and Piggy Back IOLs Some Lenses are soft and foldable to allow smaller incision sites for insertion while others are not flexible and require larger incision sites that can affect the healing process. Some lenses are sewn into the eye depending on the health of the eye or other conditions the surgeon may feel necessary Standard IOLs are usually monofocal (single powered spherical lenses) which can correct either farsighted or nearsighted but not both Premium IOLs such as TORIC IOLs help correct astigmatism and Multifocal IOLs provide correction for both far and near Blue light-filtering IOLs help filter out both the UV Lighting and the blue lighting which some experts say can contribute to cataract formation and Macular degeneration

20 DIFFERENT FORMULAS Hoffer Q Holladay 1 & 2 SRK/T Haigis Haigis-L

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22 TOPOGRAPHY OR CORNEAL MAPPING Pentacam, Orbscan and Atlas are few examples of the different types of equipment used for Corneal Mapping/Topography. Helps determine if there is astigmatism(regular vs irregular), Keratcoconus, Irregular Corneal Surface and helps when determining TORIC IOL positioning. Can determine if prior Lasik, Radial Keratometry and Penetrating Keratoplasty were done. Some Formulas used when calculating the IOL power require certain testing to be done which aids in the calculation process for better outcomes

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24 INTRA OCULAR PRESSURE Applanations, Tonopen, palpitations' and I-care are a few ways to measure the Intra Ocular Pressure. Elevated eye pressure can lead to glaucoma or other ocular problems which could lead to further complications after cataract surgery. Sometimes a combined procedure may be necessary due to narrow angles and/or elevated ocular pressure IOL s are usually thinner than the natural lens and can often lower ocular pressure by 2-3 points Narrow angles are usually resolved with Posterior IOL and usually the Anterior Chamber is deeper after surgery

25 SLIT LAMP EXAM Examining (not diagnosing) for Corneal irregularities such as corneal defects, Ulcers, nodules, Neovascularization, dryness, etc. can all have an effect on the testing results which can affect the outcome of surgery Making sure the ACD (anterior chamber depth) is not too shallow and not cause the eye(s) to go into Angle closure and possible cause damage to the eye Checking for Rubeosis (abnormal blood vessels found on the surface of the Iris) which is harder to detect if dilated The Physician will perform his own Slit Lamp Exam and guidance on how to proceed

26 DILATED FUNDUS EXAM (PERFORMED BY THE PHYSICIAN) Usually checking for over-all health of the back of the eye to include: 1. Glaucoma 2. Diabetic Retinopathy 3. Retinal Detachments or tears 4. Macular Degeneration 5. CME (cystoid Macular Edema) or ERM (Epi Retinal Membrane) 6. Inflammation 7. Bleeding, etc.

27 IN CONCLUSION A lot goes into Cataract Evaluation/Examination of each patient prior to having the surgery done. All working towards achieving the goal of making the patients happy and getting the best results possible. Whether it be the patient seeing 20/20 or just able to see more details that enable them to carry out their daily activities better. Success can be measured in many ways and being a part of one of the most successful procedures in the world speaks highly of all involved in my eyes!!!!