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What is a common characteristic of cataracts regarding their development?

  • They only affect older adults.
  • They are usually bilateral but always asymmetric. (correct)
  • They develop symmetrically in both eyes.
  • They always develop due to genetic factors.
  • What visual acuity could indicate an early mature cataract?

  • 20/50
  • 20/20
  • CF (counting fingers) (correct)
  • 20/30
  • How does the pupil's behavior differ in patients with nuclear cataracts compared to cortical cataracts?

  • Cortical cataracts cause severe glare at night, nuclear cataracts do not.
  • Nuclear cataracts worsen vision at night, cortical cataracts worsen vision during the day. (correct)
  • Cortical cataracts make peripheral vision better at night.
  • Both types affect vision equally at any time.
  • What is a potential consequence of severe cataract progression?

    <p>Glare and monocular diplopia due to differing cataract severity in each eye. (A)</p> Signup and view all the answers

    What color changes are expected as a nuclear cataract progresses?

    <p>Transitions from light yellow to dark brown. (B)</p> Signup and view all the answers

    Which factor is NOT a recognized risk factor for developing cataracts?

    <p>Genetic predisposition. (A)</p> Signup and view all the answers

    At what grade of cortical cataract does visual acuity typically measure between 20/30 to 20/40?

    <p>Grade 3. (B)</p> Signup and view all the answers

    Why is it preferred to operate on immature cataracts rather than mature ones?

    <p>Mature cataracts can cause difficulties and complications (D)</p> Signup and view all the answers

    Which surgical method involves leaving the posterior capsule intact?

    <p>Extracapsular method (A)</p> Signup and view all the answers

    What characteristics are associated with a Grade 4 Posterior Subcapsular Cataract?

    <p>Central location leading to severe glare disability (B)</p> Signup and view all the answers

    What type of traumatic cataract is characterized by the presence of flower-shaped opacities?

    <p>Moderate traumatic cataract (B)</p> Signup and view all the answers

    In which scenario might traumatic cataracts caused by radiation not lead to vision loss?

    <p>If the cataract is still in the immature stage (C)</p> Signup and view all the answers

    Which type of radiation is NOT commonly associated with cataract formation?

    <p>Microwave radiation (B)</p> Signup and view all the answers

    How is a total cataract described in relation to lens damage?

    <p>The entire lens is destroyed with the nucleus floating (C)</p> Signup and view all the answers

    What is the primary cause of mild punctate opacities in traumatic cataracts?

    <p>Mechanical trauma to the lens fibers (A)</p> Signup and view all the answers

    Which of the following is a correct statement regarding Vossius ring formation?

    <p>It involves iris pigment being stuck in the anterior capsule (D)</p> Signup and view all the answers

    What condition can lead to an increase in intraocular pressure due to pupillary block glaucoma?

    <p>Incomplete wound closure (B)</p> Signup and view all the answers

    Which medication is used to dilate the pupil but is contraindicated in hypertensive patients?

    <p>Phenylephrine 10% (A)</p> Signup and view all the answers

    What is the main function of Flurbiprofen in cataract surgery?

    <p>To reduce inflammation (A)</p> Signup and view all the answers

    What is a potential serious complication following cataract surgery?

    <p>Infectious endophthalmitis (A)</p> Signup and view all the answers

    Which treatment should be avoided for managing hyphema?

    <p>Aspirin and NSAIDs (D)</p> Signup and view all the answers

    What is the primary type of anesthesia used for cataract surgery in most cases?

    <p>Local anesthesia (C)</p> Signup and view all the answers

    What type of bleeding can be managed with aminocaproic acid after hyphema?

    <p>Antifibrinolytic bleeding (A)</p> Signup and view all the answers

    Which anesthetic agent is primarily used as a local anesthetic for cataract surgery?

    <p>Lignocaine 2% (D)</p> Signup and view all the answers

    What is a significant medication restriction for diabetic patients on the day of cataract surgery?

    <p>They should not take their diabetes medications. (D)</p> Signup and view all the answers

    When does fungal infection typically manifest after cataract surgery?

    <p>After six weeks (B)</p> Signup and view all the answers

    What is the purpose of adding adrenaline to the local anesthetic during cataract surgery?

    <p>To prolong the effect of anesthesia (C)</p> Signup and view all the answers

    Which factor is NOT included in the formula considered one of the most accurate for IOL calculations?

    <p>Body mass index (C)</p> Signup and view all the answers

    How often should antibiotic drops be administered before cataract surgery?

    <p>Every 6 hours (D)</p> Signup and view all the answers

    Which is a potential side effect of using Phenylephrine 10% on hypertensive patients?

    <p>Increased blood pressure (D)</p> Signup and view all the answers

    What type of anesthesia blocks the facial nerve during cataract surgery?

    <p>Retrobulbar anesthesia (B)</p> Signup and view all the answers

    What is a key advantage of using silicone material in surgery?

    <p>No sutures required (B)</p> Signup and view all the answers

    Which of the following is a disadvantage of silicone material?

    <p>Greater expertise required to master the technique (C)</p> Signup and view all the answers

    Laser-assisted cataract surgery utilizes which type of laser for corneal incisions?

    <p>Femtosecond laser (D)</p> Signup and view all the answers

    Which type of intraocular lens (IOL) is primarily used for astigmatism correction?

    <p>Toric lens (C)</p> Signup and view all the answers

    What characterizes the multifocal intraocular lens (IOL)?

    <p>Has concentric zones for different focal points (B)</p> Signup and view all the answers

    What is the main disadvantage of using a multifocal IOL?

    <p>Increased risk of glare and distortion (A)</p> Signup and view all the answers

    Which IOL type has the highest probability of developing posterior capsule opacification (PCO)?

    <p>PMMA lens (D)</p> Signup and view all the answers

    What is a characteristic feature of accommodative IOLs?

    <p>They bend to create accommodation (D)</p> Signup and view all the answers

    What is the primary function of femtosecond lasers in cataract surgery?

    <p>Make corneal incisions and break down the lens (C)</p> Signup and view all the answers

    Extended Depth of Focus (EDOF) IOLs are primarily designed to focus on which range of vision?

    <p>Far and intermediate-range vision (C)</p> Signup and view all the answers

    Flashcards

    Cortical Cataract

    A type of cataract where the opacities (cloudiness) begin in the outer layer (cortex) of the lens, usually appearing as grayish/white opacities.

    Nuclear Cataract

    A type of cataract where the opacities start in the central part (nucleus) of the lens. The lens changes color, progressing from light yellow to dark brown.

    Cataract Progression

    Cataracts develop gradually, and their severity impacts vision loss with variable outcomes.

    VA (Visual Acuity) changes with cataracts: Cortical

    Early cortical cataracts might only result in a minor reduction (like 20/30). More advanced stages lead to reduced VA of 20/30, 20/40, or worse, down to counting fingers

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    VA (Visual Acuity) changes with cataracts: Nuclear

    Early nuclear cataracts show minor differences. Increased progression causes more reduced VA (like 20/25-20/40).

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    Cataract Grades (Lens Opacification)

    A system for grading cataract severity using 1-4 grades. The grades correlate roughly with estimated visual loss. As grading moves to more 'severe' levels, the visual acuity loss progressively becomes more significant.

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    Cataract Risk Factors

    Factors that influence cataract formation, including UV exposure, smoking, nutrition, illnesses like Crohn's disease, and alcohol.

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    Phacoemulsification

    The current surgical method for cataract removal, involving ultrasonic vibration to break down the cataract.

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    Extracapsular Cataract Extraction

    A cataract surgery method that removes the lens contents while leaving the posterior capsule intact.

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    Intracapsular Cataract Extraction

    Cataract surgery where the entire lens, including the capsule, is removed. Used for mature cataracts and in children.

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    Posterior Subcapsular Cataract

    A cataract that develops in the back part of the lens, causing severe glare.

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    Traumatic Cataract

    A cataract caused by trauma or injury to the eye

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    Punctate Opacities

    Small, pinpoint white or pigmented spots in the lens.

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    Vossius Ring

    A ring of iris pigment found in the anterior capsule of the lens, often caused by trauma.

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    Acquired Cataracts

    Cataracts that develop over time due to various causes.

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    Radiation-induced Cataracts

    Cataracts caused by exposure to ionizing radiation (X-rays, gamma rays, UV-C) or other forms of radiation (infrared).

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    IOL Formula Input

    Seven factors (axial length, keratometry, lens thickness, and patient’s age) are used in the IOL formula.

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    Informed Consent

    Necessary procedure before cataract surgery

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    Eye Disinfection

    Povidone-Iodine 5% solution is used to disinfect the eye before surgery.

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    Pre-Surgery Antibiotic Dosage

    Instilled 2 days before surgery, every 6 hours (or 24 hours before in some cases).

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    Pupil Dilation

    Pupil is dilated for surgery; avoid certain drops for hypertension.

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    Pupil Dilation Drop (HTN)

    Phenylephrine 10% can raise blood pressure; use 2.5% with multiple drops for hypertensives

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    Flurbiprofen (Ocufen)

    Non-steroidal anti-inflammatory drops (NSAIDs) to prevent pupil closure during surgery.

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    Antiglaucoma Medications

    Glaucoma medications can be continued the day of cataract surgery.

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    Typical Anesthesia in Cataract Surgery

    Local anesthesia is used in most cataract surgeries, except for young children.

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    Anesthetic Types

    Lignocaine/Xylocaine (2%), Bupivacaine (0.75%) are common anesthetic agents for cataract surgery.

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    What is the main advantage of silicone material in cataract surgery?

    Silicone material offers faster healing time, eliminates the need for sutures and reduces the risk of re-operation.

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    What is the main disadvantage of silicone material in cataract surgery?

    Although silicone offers advantages, it increases the risk of nucleus drop during the procedure, potentially damaging the lens capsule.

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    How does a femtosecond laser improve cataract surgery?

    A femtosecond laser replaces blades and needles in certain procedures, providing precise incisions for the cornea, creating a capsulotomy, and fragmenting the lens nucleus.

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    What are the advantages of foldable acrylic IOLs?

    Foldable acrylic IOLs are less prone to developing posterior capsular opacification (PCO), also known as secondary cataract.

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    What is the main principle behind monofocal IOLs?

    Monofocal IOLs focus only on one focal point, correcting distance vision and leftover refractive error.

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    What is the primary function of toric IOLs?

    Toric IOLs are designed to correct astigmatism, a common eye condition that causes blurry vision.

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    What is the difference between multifocal and accommodative IOLs?

    Multifocal IOLs have multiple focal points, while accommodative IOLs mimic the natural bending of the lens for near vision.

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    What is the main challenge with multifocal IOLs?

    Multifocal IOLs can cause glare and distortion since the patient's eyes are trying to focus on different focal points.

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    What are EDOF IOLs and how do they differ from multifocal IOLs?

    EDOF IOLs, or Extended Depth of Focus IOLs, are designed for better far and intermediate vision compared to multifocal IOLs.

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    What is the main deficiency of accommodative IOLs?

    Accommodative IOLs lack natural bending, resulting in poor near vision and the need for glasses.

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    Incomplete Wound Closure

    Epithelial cells grow over the corneal endothelium, forming a membrane. This can cause serious complications like corneal damage, increased IOP, and angle closure.

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    Late Hyphema (Eight-Ball Hyphema)

    Blood fills the anterior chamber, damaging the corneal endothelium and increasing IOP. This can lead to secondary open-angle glaucoma.

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    Hyphema Treatment

    Avoid aspirin and NSAIDs. Treat with head inclination, steroids, IOP control, anterior chamber irrigation, and antifibrinolytic agents (e.g., aminocaproic acid).

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    Post Capsule Opacification

    Clouding of the lens capsule after cataract surgery. This can occur many months or years after the procedure.

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    Delayed Endophthalmitis

    A rare but serious infection occurring after cataract surgery. It typically manifests 6 weeks or later, suggesting a fungal infection.

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    Study Notes

    Lens Structure and Function

    • The lens capsule is a transparent, elastic membrane surrounding the lens.
    • Lens thickness is not uniform.
    • The first layer of the lens is very permeable and elastic.
    • The elasticity of the lens allows accommodation, enabling focusing at near.
    • The lens epithelium is a single layer of cuboidal cells on the anterior surface, responsible for metabolic activity.
    • Lens fibers, the bulk of the lens, are composed of lamina, forming a cortex and nucleus.
    • The lens cortex consists of hexagonal, transparent fibers arranged like an onion.
    • The lens nucleus is formed from compressed central cortex portions, undergoing sclerosis.

    Lens Chemistry

    • The lens has metabolic needs (TED) requiring a balanced process to maintain transparency.
    • Transparency maintenance is facilitated by active pumps to maintain the sodium and potassium concentration gradient.
    • The adult lens is ~65% water and ~34% protein, with the remaining 1% being inorganic compounds.
    • Crystallins (alpha, beta, gamma) are water soluble proteins crucial for lens transparency and hydration
    • Protein structure alteration contributes to loss of transparency and cataract formation.

    Cataract Epidemiology

    • Cataracts remain a leading cause of blindness, especially age-related cataracts.
    • These affect ~18 million people worldwide.
    • Cataracts also account for significant low vision cases in developed and developing countries.
    • Different types and stages cause various effects on vision.

    Classification of Cataracts

    • Congenital Cataracts: present at birth or develop during the first year of life.
    • Developmental Cataracts: develop from systemic diseases during pregnancy.
    • Metabolic cataracts
    • Chromosomal abnormalities cataracts:
      • Down Syndrome (~5% risk)
      • Patau (Trisomy 13) syndrome
      • Edward (Trisomy 18) syndrome
    • Acquired Cataracts:
      • Traumatic cataract: induced by mechanical injury or radiation.
      • Age-related cataract: typically bilateral.
      • Secondary to systemic disease.

    Cataract Management

    • Cataract management depends on the type and severity of the condition.
    • Treatment varies from no intervention to surgical removal.
    • Surgery choices depend on the density of the opacity and predicted vision outcomes.

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