Cataract (Nursing)

Review questions:
Take Free Questions on this Article

Learning Outcome

  • Describe how cataracts affect vision
  • List the causes of cataracts
  • Summarize the treatment of cataracts

Introduction

A cataract is a clouding or opacification of the normally clear lens of the eye or its capsule (surrounding transparent membrane) that obscures the passage of light through the lens to the retina of the eye. This blinding disease can affect infants, adults, and older people, but it predominates the latter group. It can be bilateral and vary in severity. The disease process progresses gradually without affecting daily activities early on, but with time, especially after the fourth or fifth decade, the cataract will eventually mature, making the lens completely opaque to light interfering with routine activities. Cataracts are a significant cause of blindness worldwide. Treatment options include correction with refractive glasses only at earlier stages, and if cataract mature enough to interfere with routine activities, surgery may be advised, which is very fruitful.

Nursing Diagnosis

  • Poor vision
  • Blurred vision
  • Halos
  • Eye discomfort
  • Anxiety

Causes

Multiple factors responsible for developing cataracts include the following:

Congenital Cataract: Can be unilateral or bilateral - studies have documented a close association between congenital cataract and maternal nutrition, infections (rubella & rubeola), and deficiency of oxygenation due to placental hemorrhage.

Age-related (Senile Cataract): Most common type of cataract

Traumatic Injury[1][2]: Most common cause of unilateral cataract in young adults

  • Perforating trauma
  • Blunt trauma: causing a characteristic flower-shaped opacity
  • Electric shock:  a rare cause of cataract, causing diffuse milky-white opacification and multiple snowflakes like opacities, sometimes in a stellate subcapsular distribution
  • Ultraviolet radiation: if intense may rarely cause true exfoliation of the anterior lens capsule and cataract
  • Ionizing radiation: usage for ocular tumor treatment and in cardiological interventions may cause posterior subcapsular opacities
  • Chemical injuries: naphthalene, thallium, lactose, galactose

Systemic Diseases:

  • Myotonic dystrophy
  • Atopic dermatitis
  • Neurofibromatosis type 2

Endocrine Diseases[3]:

  • Diabetes mellitus
  • Hypoparathyroidism
  • Cretinism

Primary Ocular Diseases:

  •  Chronic anterior uveitis: the most common cause of secondary cataract
  •  Acute congestive angle closure: may cause small anterior grey- white subcapsular or capsular opacities, glaukomflecken
  •  High myopia: may cause posterior subcapsular lens opacities and early-onset nuclear sclerosis, worsening the myopic refractive error
  •  Hereditary fundus dystrophies: i.e., retinitis pigmentosa, Leber congenital amaurosis, gyrate atrophy and Stickler syndrome, may cause posterior and anterior subcapsular lens opacities

Drugs: Corticosteroids and anticholinesterase inhibitors can cause both posterior and anterior subcapsular opacities respectively

Poor Nutrition[4]: a diet deficient in antioxidants and vitamins

Alcohol Use Disorder

Smoking

Risk Factors

Prevalence and Incidence

Many studies in 2010 reveal that cataracts are most common in the White American race, where prevalence ranges from 17 to 18% per 100 people. Blacks were the second-highest affected by cataracts, with a 13% prevalence rate, followed by Hispanics with a prevalence rate of almost 12%.

Age

Onset is gradual and progressive commonly in the older age group, typically in the fifth and sixth decade, though cases have been reported in children and the elderly as well.

Sex

Recent studies reveal that the disease is more common in women than men, with a male to female ratio of 1 to approximately 1.3.

Assessment

History

The patient may present with one of the following symptoms:

  • Decrease or blurring in vision: gradual and painless; unilateral or bilateral depending upon the eye being affected without and at mature stages even with glasses
  • Diplopia or polyopia: mostly uniocular but can be binocular- this is due to multiple refractions through clear areas between the opacities
  • Colored halos around the light: Rainbow halos; possibly due to the collection of water drops between layers of lens fibers acting as a prism splitting light into its seven colors
  • Sensitivity to glare: especially headlights of automobiles and sunlight 
  • Increased frequency to change refractive glasses: as the cataract matures, a person may visit his ophthalmologist more often for refraction
  • Disturbance in color vision: fading or yellowing of objects

Physical Findings

Following findings can be noticed during a thorough ophthalmic examination depending upon the part of the lens involved:

Visual Acuity

  • Decreased unilaterally or bilaterally depending upon the affected eye

Cortical Cataract

  • Wedge-shaped opacity with clear areas of lens matter mostly present at the periphery (incipient cortical cataract)
  • Well-developed wedge-shaped opacity (progressive cortical cataract)
  • Advanced opacity with a greyish lens, clear cortex, and an iris shadow (immature cortical cataract)
  • Findings of the immature stage but with a swollen lens due to the accumulation of fluid making anterior chamber shallow (intumescent cortical cataract)
  • The entire opaque cortex with the absence of iris shadow (mature cortical cataract)
  • Milky fluid bag with lens nucleus present at the bottom due to liquefaction of the cortex without an iris shadow and a shallow anterior chamber (hypermature cortical cataract)

Nuclear Cataract

  • Dark brown or black lens with an iris shadow
  • No fundal view due to dark opacity in the center against a red glow
  • No fourth Purkinje image

Systemic Diseases

  • Diabetes mellitus: classic snowflake cortical opacities 
  • Myotonic dystrophy: Christmas tree cortical cataract which later evolves into wedge-shaped cortical and subcapsular opacities resembling a star-like in conformation 
  • Atopic dermatitis: characteristic shield-like dense anterior subcapsular plaques 
  • Neurofibromatosis type 2: mixed opacities; can be subcapsular, capsular or cortical

Evaluation

Cataracts can be evaluated by a number of steps as follows:

History

  • The chief complaint of the patient, i.e., a decrease of vision
  • Past ophthalmic history
  • Any systemic disease causing or aggravating the symptoms

Comprehensive ophthalmic examination

  1. Visual acuity: can be assessed by Snellen chart to identify the severity of the disease and limitations in routine activities of life
  2. Refraction: Important factor to plan management
  3. Cover test: poor vision caused by cataract can be a reason for a divergent squint
  4. Slit-lamp examination
  • Pupillary responses: to check the shape of the pupil, afferent and efferent pathways and relative afferent pupillary defect
  • Adnexal examination: a thorough examination is needed to exclude any adnexal pathology, i.e., dacryocystitis, blepharitis, chronic conjunctivitis, lagophthalmos, ectropion, entropion, and tear film abnormalities - these conditions may predispose to endophthalmitis, so their diagnosis and optimization are necessary to treat cataract
  • Cornea: important to asses whether cornea will able to handle operative trauma - arcus senilis is an important finding because it can obstruct the operative field clarity
  • Anterior chamber: a shallow anterior chamber can make cataract surgery extremely difficult
  • Lens: part of the lens involved can be an important factor to plan our surgical technique - nuclear cataract is harder while cortical cataract is softer in consistency
  • Fundus examination: any pathology in the fundus, i.e., age-related macular degeneration can be an important factor to determine visual outcome after surgery that is why a thorough fundal examination is critical

Investigations

The following investigations can help diagnose and plan the management of the disease:

  • Intraocular pressure: to rule out glaucoma
  • Dark Room Tests: direct and indirect ophthalmoscopy
  • Fundoscopy: to rule out any vitreous or retinal pathology
  • Biometry: for intraocular lens (IOL) placement during surgery
  • Peripheral retinal assessment: testing the projection of light in all quadrants
  • Macular function test: like cardboard test (two-point discrimination), Maddox rod test, the laser interferometry, foveal electroretinogram, photo stress test
  • Ultrasound scan: B-scan is advised to see retinal detachment or any vitreous pathology
  • Systemic diseases: Blood glucose levels, electrocardiography, echocardiography, ultrasonography
  • Baseline tests: Complete blood count, liver function test, renal function test, bleeding profile, Hepatitis B and C screening, chest x-ray

Medical Management

The treatment choice depends upon the degree of opacity sufficient enough to cause difficulty in performing essential daily activities. Following treatment modalities are available:

  1. Medical: If visual acuity is 6/24 or better, pupillary dilatation with 2.5% phenylephrine or refractive glasses is enough to carry on routine activities, and surgery is not required. Cyclopentolate and atropine can also be useful. Recently, there are also cataracts drops under trial, which can dissolve cataracts.
  2. Surgery: If visual acuity is worse than 6/24 or there is a medical indication (phacolytic glaucoma, phacomorphic glaucoma, retinal detachment) in which a cataract is adversely affecting the health of the eye, surgery is always needed.
  • Congenital Cataract: No treatment is necessary if visual acuity is more than 6/24, and a patient can carry out their normal routine activities. Refractive glasses can be advised for the blurring of vision or diplopia. If visual acuity falls below 6/24, surgery is needed, and the surgeon can opt for one of the following surgical procedures depending upon the patient's complaints and severity of the disease.[5]
    • Irrigation and aspiration of the lens
    • Irrigation and aspiration of the lens with intraocular lenses IOL implantation
    • Irrigation aspiration of the lens with IOL, anterior vitrectomy and primary posterior capsulotomy
  • Senile Cataract: Treatment options are the following[6][7]:
    • Medical: No medical treatment is effective once the cataract has become mature.
    • Surgical: Mature cataract has a very hard nucleus, and one of the following methods are used to extract lens:
      • Extracapsular cataract extraction: a procedure of choice
      • Intracapsular cataract extraction: an old technique not used frequently due to complications 
      • Phaco-emulsification: a modification of extracapsular cataract extraction (ECCE) with less astigmatism and early visual recovery
      • Laser phacolysis: a recent advancement under trial
  • Management of general conditions before surgery: Many general health conditions require optimization before surgery for better results.
    • Diabetes mellitus
    • Hypertension
    • Myocardial Infarction
    • Angina
    • Respiratory Infection
    • Stroke
    • Leg ulcer
    • Viral hepatitis
    • AIDS
    • Epilepsy
    • Parkinson disease
    • Rheumatoid arthritis

Nursing Management

  • Check visual acuity
  • Teach patient about cataracts and their treatment
  • Teach patient about healthy diet
  • Educate about medication compliance

When To Seek Help

If the patient is unable to see seek help.

Outcome Identification

Vision restored

Monitoring

Visual acuity

Eye redness

Eye pain

Coordination of Care

Anytime a patient visits a clinic or emergency department for symptoms of visual impairment. The primary care provider should be responsible for quick referral of the patient to an ophthalmologist.[8] The management of cataract differs based on the severity of the disease, visual impairment, and age of the patient. The mainstay of treatment is usually surgical cataract extraction. Patients who have mild symptoms can receive treatment as an outpatient with refractive glasses and pupillary dilatation. Those with more severe disease or with advanced age should be advised elective surgery as a day-case procedure.[9]

Response to refractive glasses in the early stage of cataract is usually satisfactory. If outpatient therapy by refractive glasses and pupillary dilatation fails to show improvement, patients should undergo hospitalization for surgical cataract removal with intraocular lens implantation. No studies have revealed any link between prescription of systemic steroids or steroids eye drops and the recurrence or complication of cataract, and thus steroids are not routinely prescribed. For most patients who obtain prompt treatment, the results are excellent, but for those who have a delay in treatment or have a mature or complicated disease, there may be steady or poor vision following recovery.

Diagnosis and treatment of cataracts require an interdisciplinary team approach, to include primary care providers (physicians, PAs, NPs), specialists (ophthalmologists, ophthalmic surgeons), and nursing support. This approach helps to ensure timely and effective patient care and optimal outcomes. [Level 5]

Health Teaching and Health Promotion

The patients should receive education about:

  • Risk factors of the disease
  • Complications of the disease
  • Treatment options of the disease
  • Complications of the surgery
  • The regular need for a follow-up

Visual acuity charts and slit-lamp examination should be used on regular bases at every follow-up to detect any impairment in visual acuity after cataract or any complication of the surgery. The patient should be advised to wear spectacles in the sunlight to avoid damage by ultraviolet rays. A thorough systemic evaluation is advisable to rule out any systemic disease which may affect the outcome of the treatment.

Risk Management

After eye injury, refer the patient to the ophthalmologist.

Always assess visual acuity when there are vision-related issues.

Document everything

Discharge Planning

  • Wear sunglasses when going out
  • Wear protective eye wear like face shield when working with hazardous fluids and playing sports
  • Get regular eye exams
  • Comply with medications

Pearls and Other issues

Diagnosis and treatment of cataracts require an interdisciplinary team approach, to include primary care providers (physicians, PAs, NPs), specialists (ophthalmologists, ophthalmic surgeons), and nursing support. The primary care provider, nurse practitioner, and pharmacist should educate the patient on steps to prevent cataracts. The patient should be urged to wear sunglasses when going out, wear a face mask of eye goggles when working with hazardous fluids or playing sports, and see an eye doctor on a regular basis. In addition, patients prescribed corticosteroid drugs should regularly have their eyes checked to ensure that they are not developing cataracts. This approach helps to ensure timely and effective patient care and optimal outcomes. [Level 5]

Details

Nurse Editor

Sarah B. Redmond

Author

Adnan A. Nizami

Author

Bharat Gurnani

Editor:

Arun C. Gulani

Updated:

2/27/2024 12:49:15 AM

Feedback:

Send Us Your Comments

References

[1]

Shiels A, Hejtmancik JF. Biology of Inherited Cataracts and Opportunities for Treatment. Annual review of vision science. 2019 Sep 15:5():123-149. doi: 10.1146/annurev-vision-091517-034346. Epub     [PubMed PMID: 31525139]

[2]

Kiziltoprak H, Tekin K, Inanc M, Goker YS. Cataract in diabetes mellitus. World journal of diabetes. 2019 Mar 15:10(3):140-153. doi: 10.4239/wjd.v10.i3.140. Epub     [PubMed PMID: 30891150]

[3]

Allen D, Vasavada A. Cataract and surgery for cataract. BMJ (Clinical research ed.). 2006 Jul 15:333(7559):128-32     [PubMed PMID: 16840470]

[4]

Khokhar SK, Pillay G, Dhull C, Agarwal E, Mahabir M, Aggarwal P. Pediatric cataract. Indian journal of ophthalmology. 2017 Dec:65(12):1340-1349. doi: 10.4103/ijo.IJO_1023_17. Epub     [PubMed PMID: 29208814]

[5]

Hashemi H, Pakzad R, Yekta A, Aghamirsalim M, Pakbin M, Ramin S, Khabazkhoob M. Global and regional prevalence of age-related cataract: a comprehensive systematic review and meta-analysis. Eye (London, England). 2020 Aug:34(8):1357-1370. doi: 10.1038/s41433-020-0806-3. Epub 2020 Feb 13     [PubMed PMID: 32055021]

[6]

Richardson RB, Ainsbury EA, Prescott CR, Lovicu FJ. Etiology of posterior subcapsular cataracts based on a review of risk factors including aging, diabetes, and ionizing radiation. International journal of radiation biology. 2020 Nov:96(11):1339-1361. doi: 10.1080/09553002.2020.1812759. Epub 2020 Sep 22     [PubMed PMID: 32897800]

[7]

Ikeda T, Minami M, Nakamura K, Kida T, Fukumoto M, Sato T, Ishizaki E. Progression of nuclear sclerosis based on changes in refractive values after lens-sparing vitrectomy in proliferative diabetic retinopathy. Clinical ophthalmology (Auckland, N.Z.). 2014:8():959-63. doi: 10.2147/OPTH.S61372. Epub 2014 Apr 16     [PubMed PMID: 24876762]

[8]

Mamatha BS, Nidhi B, Padmaprabhu CA, Pallavi P, Vallikannan B. Risk Factors for Nuclear and Cortical Cataracts: A Hospital Based Study. Journal of ophthalmic & vision research. 2015 Jul-Sep:10(3):243-9. doi: 10.4103/2008-322X.170356. Epub     [PubMed PMID: 26730308]

[9]

Rao RC, Choudhry N. A christmas tree cataract. Canadian journal of ophthalmology. Journal canadien d'ophtalmologie. 2016 Dec:51(6):e160-e161. doi: 10.1016/j.jcjo.2016.03.005. Epub 2016 Aug 1     [PubMed PMID: 27938970]

[10]

Kolb H, Fernandez E, Nelson R, Aliancy JF, Mamalis N. Crystalline Lens and Cataract. Webvision: The Organization of the Retina and Visual System. 1995:():     [PubMed PMID: 29356473]

[11]

Ermisş SS, Oztürk F, Inan UU. Comparing the efficacy and safety of phacoemulsification in white mature and other types of senile cataracts. The British journal of ophthalmology. 2003 Nov:87(11):1356-9     [PubMed PMID: 14609833]

[12]

Guan JY, Ma YC, Zhu YT, Xie LL, Aizezi M, Zhuo YH, Wumaier A. Lens nucleus dislocation in hypermature cataract: Case report and literature review. Medicine. 2022 Sep 2:101(35):e30428. doi: 10.1097/MD.0000000000030428. Epub     [PubMed PMID: 36107580]

[13]

Ono T, Miyata K. Morgagnian Cataract. JMA journal. 2022 Jul 15:5(3):379-380. doi: 10.31662/jmaj.2022-0077. Epub 2022 Jun 24     [PubMed PMID: 35992280]

[14]

Rong X, Rao J, Li D, Jing Q, Lu Y, Ji Y. TRIM69 inhibits cataractogenesis by negatively regulating p53. Redox biology. 2019 Apr:22():101157. doi: 10.1016/j.redox.2019.101157. Epub 2019 Mar 2     [PubMed PMID: 30844644]

[15]

Vlastra W, Claessen BE, Beijk MA, Sjauw KD, Streekstra GJ, Wykrzykowska JJ, Vis MM, Koch KT, de Winter RJ, Piek JJ, Henriques JPS, Delewi R. Cardiology fellows-in-training are exposed to relatively high levels of radiation in the cath lab compared with staff interventional cardiologists-insights from the RECAP trial. Netherlands heart journal : monthly journal of the Netherlands Society of Cardiology and the Netherlands Heart Foundation. 2019 Jun:27(6):330-333. doi: 10.1007/s12471-019-1254-1. Epub     [PubMed PMID: 30843153]

[16]

Sugawa H, Matsuda S, Shirakawa JI, Kabata K, Nagai R. [Preventive Effects of Aphanothece sacrum on Diabetic Cataracts]. Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan. 2019:139(3):381-384. doi: 10.1248/yakushi.18-00177-4. Epub     [PubMed PMID: 30828014]

[17]

Moshirfar M, Webster CR, Seitz TS, Ronquillo YC, Hoopes PC. Ocular Features and Clinical Approach to Cataract and Corneal Refractive Surgery in Patients with Myotonic Dystrophy. Clinical ophthalmology (Auckland, N.Z.). 2022:16():2837-2842. doi: 10.2147/OPTH.S372633. Epub 2022 Aug 25     [PubMed PMID: 36046572]

[18]

Bair B, Dodd J, Heidelberg K, Krach K. Cataracts in atopic dermatitis: a case presentation and review of the literature. Archives of dermatology. 2011 May:147(5):585-8. doi: 10.1001/archdermatol.2010.411. Epub 2011 Jan 17     [PubMed PMID: 21242345]

[19]

Asthagiri AR, Parry DM, Butman JA, Kim HJ, Tsilou ET, Zhuang Z, Lonser RR. Neurofibromatosis type 2. Lancet (London, England). 2009 Jun 6:373(9679):1974-86. doi: 10.1016/S0140-6736(09)60259-2. Epub 2009 May 22     [PubMed PMID: 19476995]

[20]

Eballé AO, Ellong A, Ella GP, Dohvoma VA, Bella AL, Mvogo CE. Secondary cataract: an epidemiologic and clinical survey at the Yaounde Gynaeco-obstetric and Paediatric Hospital. Clinical ophthalmology (Auckland, N.Z.). 2011:5():847-51. doi: 10.2147/OPTH.S19929. Epub 2011 Jun 22     [PubMed PMID: 21750620]

[21]

Harthan JS, Opitz DL, Fromstein SR, Morettin CE. Diagnosis and treatment of anterior uveitis: optometric management. Clinical optometry. 2016:8():23-35. doi: 10.2147/OPTO.S72079. Epub 2016 Mar 31     [PubMed PMID: 30214346]

[22]

Nüssle S, Reinhard T, Lübke J. Acute Closed-Angle Glaucoma-an Ophthalmological Emergency. Deutsches Arzteblatt international. 2021 Nov 12:118(Forthcoming):771-80. doi: 10.3238/arztebl.m2021.0264. Epub 2021 Nov 12     [PubMed PMID: 34551857]

[23]

Williams K, Hammond C. High myopia and its risks. Community eye health. 2019:32(105):5-6     [PubMed PMID: 31409941]

[24]

Nentwich MM, Rudolph G. Hereditary retinal eye diseases in childhood and youth affecting the central retina. Oman journal of ophthalmology. 2013 Sep:6(Suppl 1):S18-25. doi: 10.4103/0974-620X.122290. Epub     [PubMed PMID: 24391367]

[25]

Gogate P, Sahasrabudhe M, Shah M, Patil S, Kulkarni A. Causes, epidemiology, and long-term outcome of traumatic cataracts in children in rural India. Indian journal of ophthalmology. 2012 Sep-Oct:60(5):481-6. doi: 10.4103/0301-4738.100557. Epub     [PubMed PMID: 22944764]

[26]

Yanshole VV, Yanshole LV, Snytnikova OA, Tsentalovich YP. Quantitative metabolomic analysis of changes in the lens and aqueous humor under development of age-related nuclear cataract. Metabolomics : Official journal of the Metabolomic Society. 2019 Feb 26:15(3):29. doi: 10.1007/s11306-019-1495-4. Epub 2019 Feb 26     [PubMed PMID: 30830501]

[27]

Storey P, Munoz B, Friedman D, West S. Racial differences in lens opacity incidence and progression: the Salisbury Eye Evaluation (SEE) study. Investigative ophthalmology & visual science. 2013 Apr 26:54(4):3010-8. doi: 10.1167/iovs.12-11412. Epub 2013 Apr 26     [PubMed PMID: 23572101]

[28]

Franceschi C, Garagnani P, Morsiani C, Conte M, Santoro A, Grignolio A, Monti D, Capri M, Salvioli S. The Continuum of Aging and Age-Related Diseases: Common Mechanisms but Different Rates. Frontiers in medicine. 2018:5():61. doi: 10.3389/fmed.2018.00061. Epub 2018 Mar 12     [PubMed PMID: 29662881]

[29]

Harbo HF, Gold R, Tintoré M. Sex and gender issues in multiple sclerosis. Therapeutic advances in neurological disorders. 2013 Jul:6(4):237-48. doi: 10.1177/1756285613488434. Epub     [PubMed PMID: 23858327]

[30]

Takata T, Matsubara T, Nakamura-Hirota T, Fujii N. Negative charge at aspartate 151 is important for human lens αA-crystallin stability and chaperone function. Experimental eye research. 2019 May:182():10-18. doi: 10.1016/j.exer.2019.02.023. Epub 2019 Mar 5     [PubMed PMID: 30849387]

[31]

Hejtmancik JF, Shiels A. Overview of the Lens. Progress in molecular biology and translational science. 2015:134():119-27. doi: 10.1016/bs.pmbts.2015.04.006. Epub 2015 May 27     [PubMed PMID: 26310153]

[32]

Raharja A, Whitefield L. Clinical approach to vision loss: a review for general physicians. Clinical medicine (London, England). 2022 Mar:22(2):95-99. doi: 10.7861/clinmed.2022-0057. Epub     [PubMed PMID: 35304366]

[33]

Caltrider D, Gupta A, Tripathy K. Evaluation of Visual Acuity. StatPearls. 2024 Jan:():     [PubMed PMID: 33231977]

[34]

Foster PJ, Wong TY, Machin D, Johnson GJ, Seah SK. Risk factors for nuclear, cortical and posterior subcapsular cataracts in the Chinese population of Singapore: the Tanjong Pagar Survey. The British journal of ophthalmology. 2003 Sep:87(9):1112-20     [PubMed PMID: 12928278]

[35]

Age-Related Eye Disease Study Research Group. Risk factors associated with age-related nuclear and cortical cataract : a case-control study in the Age-Related Eye Disease Study, AREDS Report No. 5. Ophthalmology. 2001 Aug:108(8):1400-8     [PubMed PMID: 11470690]

[36]

Kessel L, Andresen J, Erngaard D, Flesner P, Tendal B, Hjortdal J. Indication for cataract surgery. Do we have evidence of who will benefit from surgery? A systematic review and meta-analysis. Acta ophthalmologica. 2016 Feb:94(1):10-20. doi: 10.1111/aos.12758. Epub 2015 Jun 3     [PubMed PMID: 26036605]

[37]

Fitzgerald RJ. Medication errors: the importance of an accurate drug history. British journal of clinical pharmacology. 2009 Jun:67(6):671-5. doi: 10.1111/j.1365-2125.2009.03424.x. Epub     [PubMed PMID: 19594536]

[38]

Dougherty JM, Alsayouri K, Sadowski A. Allergy. StatPearls. 2024 Jan:():     [PubMed PMID: 31424821]

[39]

Mestre C, Otero C, Díaz-Doutón F, Gautier J, Pujol J. An automated and objective cover test to measure heterophoria. PloS one. 2018:13(11):e0206674. doi: 10.1371/journal.pone.0206674. Epub 2018 Nov 1     [PubMed PMID: 30383846]

[40]

Belliveau AP, Somani AN, Dossani RH. Pupillary Light Reflex. StatPearls. 2024 Jan:():     [PubMed PMID: 30725865]

[41]

Heathcote JG. The ocular adnexa. Saudi journal of ophthalmology : official journal of the Saudi Ophthalmological Society. 2021 Jul-Sep:35(3):167-169. doi: 10.4103/SJOPT.SJOPT_43_22. Epub 2022 Apr 18     [PubMed PMID: 35601866]

[42]

Sridhar MS. Anatomy of cornea and ocular surface. Indian journal of ophthalmology. 2018 Feb:66(2):190-194. doi: 10.4103/ijo.IJO_646_17. Epub     [PubMed PMID: 29380756]

[43]

Edawaji BSA, Gottlob I, Proudlock FA. Anterior Chamber Measurements in Healthy Children: A Cross-Sectional Study Using Optical Coherence Tomography. Translational vision science & technology. 2021 May 3:10(6):13. doi: 10.1167/tvst.10.6.13. Epub     [PubMed PMID: 34111257]

[44]

Lykstad J, Reddy V, Hanna A. Neuroanatomy, Pupillary Dilation Pathway. StatPearls. 2023 Jan:():     [PubMed PMID: 30571042]

[45]

Jammal HM, Khader Y, Shawer R, Al Bdour M. Posterior segment causes of reduced visual acuity after phacoemulsification in eyes with cataract and obscured fundus view. Clinical ophthalmology (Auckland, N.Z.). 2012:6():1843-8. doi: 10.2147/OPTH.S38303. Epub 2012 Nov 7     [PubMed PMID: 23152664]

[46]

Boote C, Sigal IA, Grytz R, Hua Y, Nguyen TD, Girard MJA. Scleral structure and biomechanics. Progress in retinal and eye research. 2020 Jan:74():100773. doi: 10.1016/j.preteyeres.2019.100773. Epub 2019 Aug 11     [PubMed PMID: 31412277]

[47]

Pi LH, Chen L, Liu Q, Ke N, Fang J, Zhang S, Xiao J, Ye WJ, Xiong Y, Shi H, Yin ZQ. Refractive status and prevalence of refractive errors in suburban school-age children. International journal of medical sciences. 2010 Oct 18:7(6):342-53     [PubMed PMID: 20975844]

[48]

Kadam RA. Informed consent process: A step further towards making it meaningful! Perspectives in clinical research. 2017 Jul-Sep:8(3):107-112. doi: 10.4103/picr.PICR_147_16. Epub     [PubMed PMID: 28828304]

[49]

Sahin A, Hamrah P. Clinically relevant biometry. Current opinion in ophthalmology. 2012 Jan:23(1):47-53. doi: 10.1097/ICU.0b013e32834cd63e. Epub     [PubMed PMID: 22081032]

[50]

Hashemi H, Yekta A, Shokrollahzadeh F, Aghamirsalim M, Ostadimoghaddam H, Hashemi A, Heydarian S, Khabazkhoob M. The Distribution of Keratometry in a Population Based Study. Journal of current ophthalmology. 2021 Jan-Mar:33(1):17-22. doi: 10.1016/j.joco.2019.06.004. Epub 2021 Mar 26     [PubMed PMID: 34084952]

[51]

Montés-Micó R, Pastor-Pascual F, Ruiz-Mesa R, Tañá-Rivero P. Ocular biometry with swept-source optical coherence tomography. Journal of cataract and refractive surgery. 2021 Jun 1:47(6):802-814. doi: 10.1097/j.jcrs.0000000000000551. Epub     [PubMed PMID: 33315731]

[52]

Petrella L, Perdigão F, Caixinha M, Santos M, Lopes M, Gomes M, Santos J. A-scan ultrasound in ophthalmology: A simulation tool. Medical engineering & physics. 2021 Nov:97():18-24. doi: 10.1016/j.medengphy.2021.09.005. Epub 2021 Sep 21     [PubMed PMID: 34756334]

[53]

Chung J, Bu JJ, Afshari NA. Advancements in intraocular lens power calculation formulas. Current opinion in ophthalmology. 2022 Jan 1:33(1):35-40. doi: 10.1097/ICU.0000000000000822. Epub     [PubMed PMID: 34854826]

[54]

Kohnen T, Strenger A, Klaproth OK. Basic knowledge of refractive surgery: correction of refractive errors using modern surgical procedures. Deutsches Arzteblatt international. 2008 Feb:105(9):163-70; quiz 170-2. doi: 10.3238/arztebl.2008.0163. Epub 2008 Feb 29     [PubMed PMID: 19633786]

[55]

Gurnani B, Kaur K. Contact Lens–Related Complications. StatPearls. 2024 Jan:():     [PubMed PMID: 36512659]

[56]

Eldaly MA, Mansour KA. Personal A-constant in relation to axial length with various intraocular lenses. Indian journal of ophthalmology. 2014 Jul:62(7):788-91. doi: 10.4103/0301-4738.138300. Epub     [PubMed PMID: 25116771]

[57]

Mehta R, Aref AA. Intraocular Lens Implantation In The Ciliary Sulcus: Challenges And Risks. Clinical ophthalmology (Auckland, N.Z.). 2019:13():2317-2323. doi: 10.2147/OPTH.S205148. Epub 2019 Nov 27     [PubMed PMID: 31819356]

[58]

Gurnani B, Mishra D, Kaur K, Heda A, Sahu A. Evolution of manual small-incision cataract surgery from 8 mm to 2 mm - A comprehensive review. Indian journal of ophthalmology. 2022 Nov:70(11):3773-3778. doi: 10.4103/ijo.IJO_1567_22. Epub     [PubMed PMID: 36308095]

[59]

Tanner V, Casswell AG. A comparative study of the efficacy of 2.5% phenylephrine and 10% phenylephrine in pre-operative mydriasis for routine cataract surgery. Eye (London, England). 1996:10 ( Pt 1)():95-8     [PubMed PMID: 8763311]

[60]

Katargina LA, Kruglova TB, Trifonova OB, Egiyan NS, Kogoleva LV, Arestova NN. [Refraction in pseudophakic eyes after surgical treatment of congenital cataracts]. Vestnik oftalmologii. 2019:135(1):36-41. doi: 10.17116/oftalma201913501136. Epub     [PubMed PMID: 30830072]

[61]

Aly MG, Shams A, Fouad YA, Hamza I. Effect of lens thickness and nuclear density on the amount of laser fragmentation energy delivered during femtosecond laser-assisted cataract surgery. Journal of cataract and refractive surgery. 2019 Apr:45(4):485-489. doi: 10.1016/j.jcrs.2018.11.014. Epub 2019 Feb 28     [PubMed PMID: 30826239]

[62]

Ren Y, Fang X, Fang A, Wang L, Jhanji V, Gong X. Phacoemulsification With 3.0 and 2.0 mm Opposite Clear Corneal Incisions for Correction of Corneal Astigmatism. Cornea. 2019 Sep:38(9):1105-1110. doi: 10.1097/ICO.0000000000001915. Epub     [PubMed PMID: 30844842]

[63]

Gurnani B, Kaur K. Phacoemulsification. StatPearls. 2024 Jan:():     [PubMed PMID: 35015444]

[64]

Moshirfar M, Milner D, Patel BC. Cataract Surgery. StatPearls. 2024 Jan:():     [PubMed PMID: 32644679]

[65]

Chylack LT Jr, Leske MC, McCarthy D, Khu P, Kashiwagi T, Sperduto R. Lens opacities classification system II (LOCS II). Archives of ophthalmology (Chicago, Ill. : 1960). 1989 Jul:107(7):991-7     [PubMed PMID: 2751471]

[66]

Chylack LT Jr, Wolfe JK, Singer DM, Leske MC, Bullimore MA, Bailey IL, Friend J, McCarthy D, Wu SY. The Lens Opacities Classification System III. The Longitudinal Study of Cataract Study Group. Archives of ophthalmology (Chicago, Ill. : 1960). 1993 Jun:111(6):831-6     [PubMed PMID: 8512486]

[67]

Chew EY, Kim J, Sperduto RD, Datiles MB 3rd, Coleman HR, Thompson DJ, Milton RC, Clayton JA, Hubbard LD, Danis RP, Ferris FL 3rd. Evaluation of the age-related eye disease study clinical lens grading system AREDS report No. 31. Ophthalmology. 2010 Nov:117(11):2112-9.e3. doi: 10.1016/j.ophtha.2010.02.033. Epub 2010 Jun 18     [PubMed PMID: 20561686]

[68]

Adrien Shun-Shin G, Brown NP, Bron AJ, Sparrow JM. Dynamic nature of posterior subcapsular cataract. The British journal of ophthalmology. 1989 Jul:73(7):522-7     [PubMed PMID: 2757992]

[69]

Labiris G, Toli A, Polychroni D, Gkika M, Angelonias D, Kozobolis VP. Liquefaction for cataract extraction. International journal of ophthalmology. 2016:9(2):306-11. doi: 10.18240/ijo.2016.02.24. Epub 2016 Feb 18     [PubMed PMID: 26949656]

[70]

Mandelblum J, Fischer N, Achiron A, Goldberg M, Tuuminen R, Zunz E, Spierer O. A Simple Pre-Operative Nuclear Classification Score (SPONCS) for Grading Cataract Hardness in Clinical Studies. Journal of clinical medicine. 2020 Oct 29:9(11):. doi: 10.3390/jcm9113503. Epub 2020 Oct 29     [PubMed PMID: 33138221]

[71]

Lee MD, Chen SP, Chen TA, Leibold C, Li Z, Fisher AC, Lin CC, Singh K, Chang RT. Characteristics of cataract surgery patients influencing patient satisfaction scores. Journal of cataract and refractive surgery. 2019 Apr:45(4):437-442. doi: 10.1016/j.jcrs.2018.11.031. Epub 2019 Feb 27     [PubMed PMID: 30824352]

[72]

Grzybowski A, Kanclerz P, Muzyka-Woźniak M. Methods for evaluating quality of life and vision in patients undergoing lens refractive surgery. Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie. 2019 Jun:257(6):1091-1099. doi: 10.1007/s00417-019-04270-w. Epub 2019 Mar 1     [PubMed PMID: 30824995]

[73]

Chew FLM, Qurut SE, Hassan I, Lim ST, Ramasamy S, Rahmat J. Paediatric cataract surgery in Hospital Kuala Lumpur - A 5-year review of visual outcomes. The Medical journal of Malaysia. 2019 Feb:74(1):15-19     [PubMed PMID: 30846656]

[74]

Comba OB, Pehlivanoglu S, Bayraktar Z, Albayrak S, Karakaya M. Pantoe Agglomerans Endophthalmitis after Phaco Surgery: The First Case in Literature. Ocular immunology and inflammation. 2020 Apr 2:28(3):479-482. doi: 10.1080/09273948.2019.1569241. Epub 2019 Feb 27     [PubMed PMID: 30811268]

[75]

Shute TS, Varma DK, Tam D, Klein T, Moinul P, Ahmed IIK, Sheybani A. Seasonal Variation in the Incidence of Malignant Glaucoma after Cataract Surgery. Journal of ophthalmic & vision research. 2019 Jan-Mar:14(1):32-37. doi: 10.4103/jovr.jovr_41_18. Epub     [PubMed PMID: 30820284]

[76]

Hoffman RS,Braga-Mele R,Donaldson K,Emerick G,Henderson B,Kahook M,Mamalis N,Miller KM,Realini T,Shorstein NH,Stiverson RK,Wirostko B,ASCRS Cataract Clinical Committee and the American Glaucoma Society, Cataract surgery and nonsteroidal antiinflammatory drugs. Journal of cataract and refractive surgery. 2016 Sep;     [PubMed PMID: 27697257]

[77]

Gurnani B,Kaur K, Posterior Polar Cataract StatPearls. 2021 Jan     [PubMed PMID: 34662063]

[78]

Gürsel Özkurt Z, Balsak S, Çamçi MS, Bilgen K, Katran İH, Aslan A, Han ÇÇ. Approach of Family Physicians to Pediatric Eye Screening in Diyarbakır. Turkish journal of ophthalmology. 2019 Feb 28:49(1):25-29. doi: 10.4274/tjo.galenos.2018.10829. Epub     [PubMed PMID: 30829022]

[79]

Zhuang M, Fan W, Xie P, Yuan ST, Liu QH, Zhao C. Evaluation of the safety and quality of day-case cataract surgery based on 4151 cases. International journal of ophthalmology. 2019:12(2):291-295. doi: 10.18240/ijo.2019.02.17. Epub 2019 Feb 18     [PubMed PMID: 30809487]