Complications Of Cataract Surgery

The chances of complications after Cataract Surgery are very less unless the patient is already suffering from another serious medical condition or an eye condition. 

Still, it is essential to know about the complications of cataract surgery for your Ophthalmology paper. So read this blog thoroughly till the end to ace your NEET PG preparation. 

Complications of Cataract Surgery

The complications of cataract surgery can be divided into three types:

• Operative complications
• Acute post-operative complications
• Chronic post-operative complications

Operative Complications

• These are the following operative complications:

1. Posterior Capsular Tear
   • This can be of two types -
     • Without vitreous loss
     • With vitreous loss: This condition can lead to more complications like-
       • Cystoid macular edema (CME)
       • Retinal detachment
       • Endophthalmitis
       • Glaucoma

2. Supra-Choroidal Haemorrhage

• Etiology: This can occur while giving anesthesia or due to sudden changes in intraocular pressure (IOP).
• It happens due to the puncturing and bleeding of short-posterior ciliary arteries.
• Management: Immediately stop the surgery and re-suture everything. Don’t drain the blood during this acute phase, instead wait for 7 days. If it doesn’t resolve in a week, then a sclerotomy is done.
• Expulsive hemorrhage: If the hemorrhage becomes severe, it can lead to the extrusion of the intraocular contents.
• This expulsive hemorrhage can lead to:
  Iris prolapses.
  ↓
  Vitreous prolapse.
  ↓
  Loss of red reflex
  • Short posterior ciliary artery supplying choroid is the source of bleed. 
  • Management: stop surgery and re-suture immediately

UGH Syndrome (Uveitis Glaucoma Hyphema)

• It is mainly a complication of AC IOL (Anterior chamber intraocular lens).

DM (Descemet Membrane) detachment

• Descemetopexy is done to manage this complication by injection of air which will result in the reattachment of the membrane.

Acute Postoperative Complications

These are the following acute postoperative complications:

Shallow Anterior Chamber

• Etiology: This can happen due to reasons
  • Leak: This can be confirmed by doing the Seidel test.
    • Seidel Test: Fluorescein dye is applied and in the area of aqueous leakage the fluorescein dilutes.
  • Pupillary block glaucoma:
    • The aqueous is collected in the posterior chamber due to the blockade and thus the pressure created pushes the iris forward causing iris bombe which ultimately results in glaucoma. It results in a shallow anterior chamber.
  • Malignant/ Ciliary block glaucoma: It is also known as aqueous misdirection syndrome.
    • The aqueous is collected in the vitreous cavity in this condition. The aqueous accumulated posteriorly will push the anterior chamber forward making the chamber shallow.
    • Treatment: Atropine is given to relieve the pressure by breaking the blockade.
  • Cilio-choroidal detachment

Endophthalmitis

• It is the purulent inflammation of intraocular fluids usually due to infection.
• Etiology: The most common etiological factor that causes the acute onset of endophthalmitis is Staphylococcus epidermidis. The hallmark feature of endophthalmitis is progressive vitritis.
• Clinical features: All these signs and symptoms rapidly progresses.
  • Worsening of vision
  • Redness
  • Pain
  • Photophobia
  • Blepharospasm
  • Discharge
• On examination: 
  • There is a progressive diminution of vision.
  • Lid swelling
  • Chemosis
  • Corneal edema
  • Hypopyon: It is the presence of pus cells in the anterior chamber.
  • All the signs of anterior uveitis may be present.
  • Vitritis
  • Fundal glow is absent.
  • Retinal peri phlebitis

Treatment: 

• According to EVS (endophthalmitis vitrectomy study) 
• Vision: As per the vision, treatment can be of two types :
  • If there is no hand movement then the treatment is pars plana vitrectomy (the eye is entered 3.5 mm lateral to the limbus).
  • If there is hand movement and above then the patient is treated conservatively.
• The treatment of choice for endophthalmitis is intravitreal antibiotic injections. The antibiotics given are ceftazidime and vancomycin. Also, small doses of dexamethasone to control the inflammation. Systemic antibiotics that are given due to their higher ocular penetration are quinolones.
• Management of associated uveitis is done by giving cycloplegics and topical steroids under the cover.

The most common pathogen that causes post-traumatic endophthalmitis is Bacillus cereus. Antibiotics that are contraindicated to be given by vitreal injection are gentamycin and amikacinas they are toxic to the macula. In case of fungal infection, Amphotericin B and Voriconazole can be given intravitreally. The most common fungus that causes endophthalmitis and lids infection is Candida albicans. The most common fungus that causes orbital cellulitis is Mucormycosis. The most common fungus that causes keratitis is aspergillus fumigatus.

Chronic Postoperative Complications

1. Endophthalmitis
   • In this case, it will be late onset usually after 9 months.
   • Etiology: It is caused by Propionibacterium acne.
     • If it is present in the bag and causes infection at a later stage then the condition is called saccular ophthalmitis.
   • Clinical features: They are as follows -
     • Painless condition
     • Mildly progressive diminution of vision.
   • On examination:
     • All the signs of low-grade anterior uveitis are seen.
     • Mild vitritis
   • Treatment:
     • An intravitreal antibiotic is given i.e., vancomycin.
     • Systemic quinolones are given, usually, moxifloxacin is given.
     • Management of associated uveitis is done by giving cycloplegics and topical steroids under the cover.
   • Other cause of slow onset is fungal.
     • Mc fungus causing keratitis is aspergillus fumigatus.
     • Mc fungus causing endophthalmitis is candida albicans. 
     • Mc fungus causing orbital cellulitis is mucor mycosis.
2. Posterior capsular opacification/ after cataract/ secondary cataract
   • It is the most common long-term complication of cataract surgery.
   • Morphologically this is divided into three types:
     • Diffuse/Fibrosis: This is caused due to fibrous metaplasia of the epithelial cell.
     • Elschnig pearls: These are the migrated epithelial cells.
     • Soemmerring ring: This is due to the proliferation of the residual cells.

Clinical Features: Blurring of vision and later results in the diminution of vision.

Treatment: The treatment of choice is NdYAG laser posterior capsulotomy.

Which IOL will have the least chance of causing posterior capsular opacification? The answer is hydrophobic acrylic.

Cystoid Macular Edema

• It is a reversible kind of macular edema. It is also known as Irvine Gass Syndrome. In this, due to vitreous loss, there will be cystoid macular edema which will lead to a vitreous touch which further causes keratopathy.

Anterior capsular contraction and fibrosis

• It is managed by NdYAG anterior capsulotomy.

Displacement of IOLs

• Lens can get displaced either up, down, or lateral.
• IOL displaced lateral
• IOL displaced upwards- sunrise syndrome
• IOL displaced downwards- sunset syndrome

Dysphotopsia

• These are some annoying visual phenomenon due to mono focal IOLs.

Refractive Surprise

• It is a significant residual refractive error.
• Treatment: There are three options for treatment -
  • Prescribe specs or contact lenses.
  • Exchange of the IOLs.
  • Piggyback IOLs

Congenital Cataract

This can be of two types:

• Developmental: It occurs in people >1 year, so in adult and infantile nuclei.
• Infantile: It occurs in babies <1 year of age so in embryonic and foetal nuclei.

Etiology: These are the reasons why a child can develop cataracts (Bilateral)

• TORCHS: It stands for toxoplasmosis, rubella, cytomegalovirus, herpes, and syphilis. Any of these infections in the first trimester can cause congenital cataract.
• Radiation exposure in the first trimester. Use of teratogenic drugs in the first trimester.
• Metabolic causes: These are as follows
  • Galactosemia
  • Fabry’s disease
  • Lewis syndrome
• Hepatic disorders like Wilson’s disease
• Chromosomal disorders like Down’s syndrome- blue dot cataract 
• Genetic: There is a positive family history of the disease, and the inheritance is autosomal dominant.
• Birth trauma and some cases of ROP (retinopathy of prematurity) can cause unilateral congenital cataracts.

Blue dot cataract or punctate cataract is a feature of Down’s syndrome. The most common congenital cataract is the blue dot cataract. The most common congenital cataract causing marked diminution of vision is lamellar cataract. Genes that are responsible for congenital cataracts are the CRY-G gene (crystalline gamma), Cx gene (connexins), and MIP gene (major intrinsic protein).

Types of congenital cataracts

Blue dot cataract

• This is the most common type of congenital cataract. Bluish dots are seen on the lens as cataract opacities. Both nucleus and the cortex of the lens are affected.

Cataracta pulverulenta

• In this, the lens has a powdery appearance. Both nucleus and the cortex of the lens are affected.

Lamellar/zonular cataract

• Due to some environmental insult, one lamella can develop cataracts, but the adjacent areas are clear.  Over this cataract, there can be small spoke-like opacities called the RIDERS.
• Etiology: This condition can develop due to vitamin D deficiency or rubella infection. This only involves the foetal nucleus. This is the most common infantile cataract. This this most common congenital cataract causing marked diminution of vision

Anterior polar cataract

• This is generally associated with the persistent pupillary membrane.

Posterior polar cataract

• This can be associated with remnants of hilar tissues known as Mittendorf dots. An onion ring appearance is seen.

Coronary cataract

• Peripheral cortical opacities are seen in this condition.

Sutural cataract

• The opacities are only seen on the sutures. From the front, it looks like Y and from the back, it looks like an inverted Y.

Total congenital cataract

• Whole lens is opaque.

Clinical Features

• The child with present with congenital cataracts:
• Leukocoria: It is also known as the white eye reflex.

Investigation: 

• First a detailed eye examination is to be done. 
• Then the investigation is divided into two types -
  • Ocular: A scan and B scan are done.
  • Systemic: It is not done in unilateral cataracts or bilateral cataracts with positive family history. It is done to find other causes of cataracts. This can be of two types:
    • Serum analysis: In this glucose, galactose, calcium, phosphorus levels, and TORCHS are checked.
    • Urine analysis: 
      • Reducing substance in the urine then it is galactosemia.
      • Amino acids in the urine indicate Lewis’s syndrome.
      • If sediments are detected in the urine, then it is Fabry’s disease.
      • Detection of copper in the urine indicated Wilson’s disease.
      • Blood in the urine indicates Alport’s syndrome.

Treatment of congenital cataract

• According to the SRK formula, P=A-2.5L-0.9K, so earlier the congenital cataracts were treated after 2 years of age. However, every child used to develop amblyopia due to this delay. 
• This is because the fovea reflex formation (macula maturation or fixation reflex) is completed by 5-6 months of age, but the child has cataracts, so the vision is never 6/6.
• The ideal time to operate:
  • It should not be done before 1 month of age due to the high chances of developing inflammatory glaucoma.
  • After 1 month of age, it should be done as soon as possible.
  • Unilateral: In this case, the treatment should be done as soon as possible.
  • Bilateral: In this case, the treatment should be done after 6 weeks of age.
• Dhane's criteria
  • If the child is <2 years, under correct the P value by 20%.
  • If the child is 2-8 years old, then under correct by 10%.
• Treatment of choice: It is lens aspiration with primary posterior capsulotomy with anterior vitrectomy.

Congenital rubella syndrome

• The triad of this disease is CHD - cataract, heart defects, and deafness. The most common type of cataract is the nuclear pearly cataract.
• Ocular features of rubella: They are-
  • Microphthalmos: When the axial length is <21 mm or at 19 years the axial length is <19mm.
  • Rubella keratitis.
  • Angle anomaly leading to glaucoma.
  • Nuclear pearly cataract: This is the second most common ocular feature.
  • Pigmented retinopathy: Salt and pepper fundus is seen. This is the most common ocular feature.

Differential diagnosis of salt and pepper fundus: These are - Rubella Syphilis Myotonic dystrophy Retinitis pigmentosa: A variant of this condition is sine pigmento. Laber’s amaurosis Amaurosis: It is the total loss of vision. Amblyopia: It is the partial loss of vision. Amaurosis fugax: It is the transient loss of vision in a curtain-like manner.

Subluxation of Lens

• It is the partial dislocation where a part of the lens is still in the patellar fossa.

Etiology: 

• It can be of two types -
  • Acquired: 
    • The most common cause is trauma.
    • Buphthalmos
    • High myopia
    • Pseudo exfoliation syndrome
    • Chronic uveitis
    • Hyper mature nuclear sclerotic cataract
  • Genetic: It is called ectopia lenses. This can be of three types -
    • Simple EL: Displace of lens takes place.
    • It includes familial EL which is autosomal dominant.
    • Ectopia lenses et pupillae: The pupil is also displaced in the opposite direction of lens displacement.
    • EL associated with systemic diseases

EL associated with systemic diseases

• Marfan’s syndrome: It is a superio-temporal ectopia lenses.
• Homocystinuria: It is inferio-nasal ectopia lenses.
• Wiell marchesani syndrome: It has an inferior subluxation and microspherophakia. The patient is short stature with stubby fingers.
• Ehler-Danlos syndrome: The subluxation has no specific direction. Also, a blue sclera is seen which is a very thin sclera such that the underlying uveal tissues are visible.
• Sulfite oxidase deficiency
• Hyperglycinemia
• Stickler syndrome: The most common ocular feature is retinal detachment.

Ocular features of Marfan’s Syndrome

• Axial myopia
• Megalocornea: It is the most prominent feature.
• Cornea plana
• Ectopia lenses which is superio-temporal: It is the most common feature.
• Hypoplasia of dilator pupillae.
• Lattice degeneration of the retina.
• Rhegmatogenous retinal detachments.

Management

• Spectacle correction from phakic area or aphakic area, whichever is more.
• Surgery: It depends on two factors –
  • Subluxation is < 9 o’clock hours: Usage of capsular tension rings or CRS (capsular ring segments) is done.
  • Subluxation is > 9 o'clock hours: Removal of the lens is done i.e., ICCE.

And that is everything you need to know about cataract surgery complications to ace your Ophthalmology preparation for NEET PG exam. For more informative blog posts like this, donwload the PrepLadder App and follow our blog!