​Kembara Xtra - Medicine- Cataract

​Kembara Xtra - Medicine- Cataract
Introduction 
Any localized or widespread opacity or discoloration of the lens is referred to as a cataract; however, the term is typically only used to describe alterations that impair visual acuity.
 Etymology: called from the opaque frothy look; from Latin catarractes, meaning "waterfall"
Estimated 20 million individuals globally suffer from the leading cause of blindness.
The following types are among them:
- Age-related: 90% of cases are connected to age.
- Metabolic (Wilson disease, hypocalcemia, and diabetes with an accelerated sorbitol pathway)
- Congenital (10-38% of childhood blindness; 1 in 250 infants)
- Myotonic dystrophy and atopic dermatitis (AD) are systemic diseases that are connected.
- Secondary to an ocular condition that is considered to be difficult, such as uveitis linked to sarcoidosis or juvenile rheumatoid arthritis or tumors like melanoma or retinoblastoma.
Traumatic (such as heat, electric shock, radiation, concussion, injuries to the eye that perforate it, and intraocular foreign bodies)
- Nutritional/toxic (such as corticosteroids)
Morphologically speaking:
Because of the increasing refractive index of the lens, nuclear aging of the central lens nucleus is commonly related with myopia. As a result, some elderly individuals may once again be able to read without glasses, a condition known as "second sight."
- Radial, spoke-like opacities; cortical: outer part of lens; may involve anterior, posterior, or equatorial cortex.
- Subcapsular: Posterior subcapsular cataract affects vision more severely than nuclear or cortical cataract; patients with miosis are particularly troubled; near vision is typically more severely impacted than distance vision System(s) affected: elderly Geriatric Considerations tense
All persons over the age of 70 should expect to develop cataracts to some extent.

Child Safety Considerations
Leukocoria may be a possible presenting symptom Pregnancy considerations (including drugs, metabolic dysfunction, intrauterine infection, and malnutrition)

Incidence and prevalence in Epidemiology

Incidence

Cataracts are to blame for 48% of the 37 million cases of blindness that exist worldwide.
 The primary factor contributing to curable blindness and visual loss in underdeveloped nations 
 Predominant age: varies with cataract type

Prevalence
Based on the demographics of the population, cataract prevalence and kind might vary greatly.
Age-related cataract is thought to affect 50% of those aged 65 to 74 and 70% of people over 75.

Pathophysiology and Etiology 

cataract caused by aging:
- As layers of lens fibers are continuously added throughout the course of a person's life, a hard, dehydrated lens nucleus that affects vision is created (nuclear cataract).
- As we age, the biochemical and osmotic equilibrium that is necessary for lens clarity is altered; as a result, the outer layers of the lens hydrate and become opaque, impairing vision.
• Congenital
- Usually no known cause
- Drugs (sulfonamides, corticosteroids in the first trimester)
- Metabolic (mom has diabetes, fetus has galactosemia)
- An intrauterine infection in the first trimester, such as rubella, herpes, or the measles
- Undernutrition in mothers
Other varieties of cataracts
- A biochemical/osmotic imbalance that impairs lens clarity is a common symptom.
- Local variations in the distribution of lens proteins cause light dispersion (lens opacity).

Genetics Congenital (such as chromosomal problems [Down syndrome]) Although the genetics of age-related cataracts is still unknown, it is likely to be a multifactorial issue.

Risk factors include aging, smoking, exposure to UV rays from the sun, diabetes, prolonged use of high-dose steroids, having a healthy family history, and alcohol.


Protection through high-dose, long-term steroid use (systemic therapy > inhaled treatment) Care with UV protective eyewear Avoidance of tobacco products Effective control of diabetes Protective methods using pharmaceutical intervention (e.g., antioxidants, acetylsalicylic acid [ASA], hormone replacement therapy [HRT]) show no proven benefit to date.


Accompanying Conditions 
Diabetes, particularly when there is inadequate glucose regulation
Myotonic dystrophy (visually harmless alteration in 90% of patients in third decade; becomes debilitating in fifth decade)
AD (cataracts commonly develop bilaterally in the second to fourth decades in 10% of persons with severe AD)

Type 2 Neurofibromatosis
Associated ocular disease, or "secondary cataract" (e.g., high myopia, acute [or recurrent] angle-closure glaucoma, chronic anterior uveitis); drug-induced (e.g., steroids, chlorpromazine);
The trauma

Introducing History 

cataract caused by aging:
- Issues with visual acuity in any lighting situation - Falls or accidents; injuries (such as a hip fracture) - Reduced visual acuity, fuzzy vision, distortion, or "ghosting" of pictures
Congenital cataracts are frequently asymptomatic; parents observe their child's strabismus or visual inattentiveness.
- May also have diminished optical acuity
- The proper clinical history or symptoms to aid in diagnosis

clinical assessment 

Assessment of visual acuity for all cataracts - Glare testing enables further evaluation of visual impairment.
Age-related cataract: opacity of the lens during an eye exam
Congenital conditions include: - Lens opacity that develops within three months of birth or at birth; - Leukocoria (white pupil); - Strabismus; - Nystagmus; - Signs of an Associated Syndrome (such as with Down or Rubella Syndrome);
Note: It is important to rule out ocular tumors at all times; retinoblastoma can be treated and diagnosed early for a chance at survival.
 In cases of other types of cataract, physical characteristics (such as metabolic or trauma) may be accompanied by a loss in visual acuity.


Multiple Diagnoses 
An opaque-appearing eye may be caused by malignancy, lens opacities, retinal detachment, or opacities of the cornea (such as scarring, edema, or calcification). A diagnosis should be made via a meticulous ophthalmoscopic examination or a biomicroscopic examination (slit lamp).

The loss of vision in the elderly is frequently caused by a combination of events, including cataract and macular degeneration.
Congenital lens opacity in the absence of other ocular pathology may induce severe amblyopia. Age-related cataract is relevant if symptoms and an ophthalmic exam confirm cataract as a main cause of vision impairment. Relative afferent pupillary response defects are not caused by cataract. abnormal pupillary responses necessitate additional testing to rule out other pathologies.

Diagnostic tests and laboratory results 
Evaluation of visual quality may include tests for glare and contrast sensitivity.
Potential acuity meter testing for the assessment of retinal/macular function
The underlying process's workup

Interpretation of Tests
Although consistent with the type of cataract detected, the diagnosis is made by a clinical examination.


The United States performs 1.64 million cataract extractions each year as an outpatient procedure. 
UV radiation protection for the eyes


There are currently no drugs available to stop or slow the development of cataracts.

Motives for the Referral 
A second evaluation from another ophthalmologist may be necessary if the patient has cataracts and the symptoms do not appear to support the suggestion for surgery.

Surgical Procedures Age-related Cataract: - Surgical removal is required if symptoms of vision impairment are upsetting to the patient, obstructing lifestyle or employment, or creating a fall or injury risk.
– Significant cataracts may grow gradually, making it possible for the patient to be unaware of how it has altered their way of life. The patient says there are "no problems," but the doctor may notice a large cataract. Therefore, evaluation calls for a strong doctor-patient interaction.
– by the primary care physician, before surgery:
Patients taking anticoagulants may need to temporarily stop taking them 1 to 2 weeks prior to surgery, if possible (though this is typically not essential; talk to your ophthalmologist about this).

Patients should inform their ophthalmologist if they have ever used a -blocker, such as tamsulosin (Flomax), as there is an increased risk of developing intraoperative floppy iris syndrome (IFIS), even in those who no longer use these medications.
- Anesthesia: often topical with sedation and vital signs monitoring, although occasionally local injection is also used.
- Surgical procedure: cataract extraction using phacoemulsification through minute incisions made with a blade or laser, followed by implantation of a prosthetic intraocular lens. The power of the intraocular lenses is calculated based on the size of the eye and the curvature of the cornea, and is typically used to correct for distance vision.

Laser-assisted cataract surgery: Using a laser, certain cataract surgery procedures can be completed automatically, including making incisions, releasing the lens capsule, and shattering the cataract before phacoemulsification is used to remove it surgically.
- After surgery, patients often receive a protective eye shield as instructed, a topical antibiotic, NSAIDs, and steroid eye medicines; they should also refrain from lifting or bending for at least a week. generally protecting the eyes.
Surgery is used to remove the cataract in cases with congenital cataracts. Surgery may be necessary for newborns within a few days to lessen the chance of severe amblyopia. Because eyes are developing, the use of lens implants is debatable.
- Postoperative care: hard for the doctor and parents; refractive correction of the operated eye, with frequent follow-up exams; long-term patching regimen for the good eye to counteract amblyopia

Patient Follow-Up Monitoring
The prescription for glasses or contact lenses may alter as the cataract develops in order to preserve vision. Surgery is necessary when this is no longer effective and interferes with the patient's everyday activities.
To improve near and/or far visual acuity after surgery, spectacle correction may still be necessary.
Several weeks after surgery, refraction is frequently advised.


If there are no past or concurrent ocular diseases, the prognosis for removing a cataract is good: 94.3% of otherwise healthy eyes attain best-corrected visual acuity of 20/40 or better. Success rates are decreased when conditions like diabetes and glaucoma are present.

After cataract surgery, posterior capsular opacification can develop and lead to a reduction in vision (14.7–42.7% of eyes, often treated with Nd:YAG laser capsulotomy in the office at a rate of 4–25.3%).
The prognosis for congenital cataracts is frequently worse due to the significant probability of amblyopia.


Complications might range from delayed visual recovery or ongoing eye pain to blindness and eye loss.
In general, complications are rare (2% of eyes).
Poor preoperative visual acuity is associated with surgical difficulties. A posterior capsular rupture is notable among the consequences since it may necessitate additional measures during surgery.

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