Morgagnian Cataract

From EyeWiki
Original article contributed by: Sabin Sahu, MS
All contributors: Alpa S. Patel, M.D. and Sabin Sahu, MS
Assigned editor: Neeta Varshney, MD
Review: Assigned status Update Pending by Alpa Patel, MD on February 4, 2016.



Morgagnian cataract
Classification and external resources
Morgagnian cataract

Morgagnian cataract

ICD-10 H25.2
DiseasesDB 11945


Disease Entity

Morgagnian Cataract is recognized by the following codes as per the International Classification of Diseases (ICD) nomenclature:
ICD - 10

  • H25.20 Age-related cataract, morgagnian type, unspecified eye
  • H25.21 Age-related cataract, morgagnian type, right eye
  • H25.22 Age-related cataract, morgagnian type, left eye
  • H25.23 Age-related cataract, morgagnian type, bilateral

Disease

Morgagnian cataract is a form of hypermature cataract formed by liquefaction of the cortex and sinking of the dense nucleus to the bottom of the capsular bag.[1]

Epidemiology

In most developed countries cataract surgeries are done as soon as it becomes visually disabling. But due to late presentation of the patients, morgagnian cataracts are commonly seen in developing countries.

Risk Factors

It is commonly age related acquired condition. However factors that increase the risk of cortical cataracts like chronic sunlight exposure, uncontrolled diabetes are the risk factors.

Pathophysiology

It appears that morgagnian cataract is a special form of cortico-nuclear cataract. It is assumed that the process of fibre dissolution which is encountered in cortical cataract in general is speeded up and occurs en masse in morgagnian cataract.[2] Histopathologically, accumulation of eosinophilic fluid between lens cells with displacement and degeneration of bordering cells characterize cortical cataracts. Spherical droplets or globules of released protein from the breakdown of cortical cell walls are called morgagnian globules.These globules may accumulate and may eventually replace the entire cortex and result in a mature morgagnian cataract. The central dense nucleus at this point would become gravity dependent often displaced inferiorly to the lower equatorial region of the lens within the capsular bag. [3]

Diagnosis

Morgagnian cataract is a clinical diagnosis.

Signs

  • Decreased visual acuity - gradually progressive, painless
  • Dense nucleus floating freely in the liquified cortex
  • Flecks of calcium deposits in the anterior capsule may be seen
  • Absence of red fundus glow in retinoscopy

Symptoms

  • Blurring of vision
  • Glare

Complications

  • Morgagnian cataract may undergo spontaneous rupture into anterior chamber causing inflammatory reaction, which is known as phacoanaphylactic uveitis.
  • It may also be complicated with phacolytic glaucoma when the lens protein leaked through the anterior capsule clog the trabecular meshwork obstructing the aqueous outflow.

Preoperative workup

  • Assessment of visual potential by checking accurate light projections and swinging flashlight test to detect a relative afferent pupillary defect.
  • B-scan ultrasound study for posterior segment evaluation to rule out complicated co-existing intraocular diseases.
  • Measurements of the corneal refractive power and immersion A-scan to determine the power of the IOL required.

Differential diagnosis

  • White cataract
  • Traumatic cataract

Management

Surgical removal of the cataractous lens followed by intraocular lens implantation is the treatment modality of choice.

Surgery

Extracapsular Cataract extraction (ECCE), Small incision cataract surgery (SICS) or phacoemulsification can be performed for the cataract extraction. This is followed by intraocular lens implantation (posterior chamber intraocular lens (PCIOL )/ anterior chamber intraocular lens (ACIOL))

Surgical challenges

  • Creation of continuous curvilinear capsulorhexis is challenging due to increased intralenticular pressure.
  • The surgical view may be poor due to lack of red reflex or due to the leaked liquified cortical material into the anterior chamber.

Surgical Complications

  • Uncontrolled radial tear of anterior capsule
  • Posterior capsular rent
  • Nuclear drop into the vitreous
  • Endothelial cell damage

Prognosis

  • Patients should be counselled about the increased risk of complications and the possible need of more than one surgeries to achieve the best visual outcome.
  • Preoperative assessment for projection of light and relative afferent pupillary defect are important prognostically.
  • Patients should also be explained about the possible binocular diplopia due to a longstanding loss of fusion.

Additional Resources

  • Basic Clinical Science Course (BCSC) of the American Academy of Ophthalmology. Section 11. 2014 - 2015
  • Roger F. Steinert. Cataract surgery 3rd edition. CA, USA: Elsevier Inc.; 2010
  • American Academy of Ophthalmology. Cataract/Anterior Segment: Morgagnian cataract Practicing Ophthalmologists Learning System, 2017 - 2019 San Francisco: American Academy of Ophthalmology, 2017.

Reference

  1. Basic Clinical Science Course (BCSC) of the American Academy of Ophthalmology. Section 11. 2014 - 2015.
  2. Bron AJ, Habgood JO. Morgagnian cataract. Trans Ophthalmol Soc U K. 1976 Jul;96(2):265-77.
  3. Roger F. Steinert. Cataract surgery 3rd edition. Chapter 1, The pathology of cataracts. CA, USA: Elsevier Inc.; 2010