Morgagnian cataract is a special form of hypermature cataract. It occurs when a cataract progresses beyond the hypermature stage, causing the lens cortex to liquefy (dissolve), and the hard central nucleus sinks to the bottom of the lens capsule due to gravity.
The name derives from the 18th-century Italian anatomist and pathologist Giovanni Battista Morgagni.
In ICD-10, it is classified under the following codes: H25.20 (unspecified), H25.21 (right eye), H25.22 (left eye), H25.23 (bilateral).
The stages of cataract progression are summarized as follows.
| Stage | Condition |
|---|---|
| Immature cataract | Opacity limited to part of lens; fundus visible |
| Mature cataract | No transparent area; fundus difficult to see |
| Hypermature cataract | Progressed beyond maturity; cortical degeneration |
| Morgagnian cataract | Cortical liquefaction and sinking of the nucleus |
Epidemiology: In most developed countries, cataract surgery is performed early when visual impairment occurs, so Morgagnian cataract is rare. In developing countries, it is more common due to delayed consultation. Aging is the main cause, but chronic sun exposure, poorly controlled diabetes, intraocular inflammation, and steroid use are also risk factors that accelerate cataract progression.
Slit-lamp microscopy findings are key to diagnosis.
When a narrow slit beam of 16–20× magnification is focused at a 60-degree angle on the superior part of the nucleus using a slit-lamp microscope, a triangular space bounded anteriorly by the anterior capsule, posteriorly by the posterior capsule, and at the base by the lens nucleus can be seen. This is the triangle sign, a characteristic finding in Morgagnian cataract where the cortex is liquefied and the nucleus has sunk inferiorly.
Morgagnian cataract is considered an advanced form of cortical cataract. It occurs when the process of fiber dissolution seen in typical cortical cataracts accelerates and occurs collectively.
Histopathologically, it is characterized by accumulation of eosinophilic fluid between lens cells and displacement and degeneration of border cells. Spherical particles of protein released by the breakdown of cortical cell walls form Morgagnian globules, which accumulate and replace the entire cortex, leading to a mature state.
Risk factors are common to cataracts in general, but the greatest factor is loss of treatment opportunity (delayed consultation):
Morgagnian cataract is a clinical diagnosis.
Preoperative evaluation is important to ensure safe surgery.
Surgical removal of the cataractous lens and intraocular lens (IOL) implantation is the only treatment.
Surgery for Morgagnian cataract is highly difficult and requires addressing the following technical issues.
Anterior capsule-related issues:
Reduced visibility of the surgical field:
Posterior capsule laxity:
Intraocular lens scaffold technique: A specialized technique reported to prevent posterior capsule rupture during phacoemulsification of Morgagnian cataract[¹]. An intraocular lens is pre-positioned as a “scaffold” to support the fragile posterior capsule during nucleus emulsification. It constantly supports the lax posterior capsule and also reduces stress on the zonular fibers. Alternative approaches include nucleus management techniques to control the mobile nucleus[²] and phacoemulsification combined with a capsular tension ring to stabilize the capsule[³].
Intraoperative Complications
Anterior capsule radial tear: Uncontrollable tear in the fibrotic anterior capsule.
Posterior capsule rupture: Rupture due to phacoemulsification energy on the lax posterior capsule.
Nucleus drop into vitreous: A serious complication that occurs when the posterior capsule is completely ruptured.
Corneal endothelial damage: Endothelial cell damage due to excessive emulsification energy and ultrasound.
Complications (preoperative)
Phacoantigenic uveitis: Inflammation caused by spontaneous rupture of lens proteins into the anterior chamber.
Phacolytic glaucoma: Liquefied lens proteins clog the trabecular meshwork, obstructing aqueous outflow and increasing intraocular pressure.
Secondary glaucoma: Elevated intraocular pressure due to inflammation and angle-closure mechanisms after spontaneous rupture of the lens capsule.
Preoperative light perception assessment and the presence of a relative afferent pupillary defect are important prognostic factors. If there is no damage to the optic nerve or retina, significant visual recovery can be expected after successful surgery. However, if optic nerve or retinal damage due to long-term lack of treatment is present, visual recovery may be limited.
Morgagnian cataract is a special form of cortico-nuclear cataract, thought to occur when the fiber dissolution process seen in cortical cataracts is accelerated and occurs en masse.
Various factors, including aging, cause degeneration of lens proteins. Lens proteins (α, β, γ crystallins) undergo modifications such as proteolysis, deamidation, oxidation, glycation, and racemization, leading to insolubilization and aggregation, which scatter light and form opacities (cataracts).
As cortical cataract progresses, eosinophilic fluid accumulates between lens cells, and border cells undergo displacement and degeneration. When cortical cell walls collapse, internal proteins are released as spherical particles (Morgagnian globules). Accumulation of these globules replaces the entire cortex, leaving only the hard central nucleus within the lens capsule. The hard nucleus becomes gravity-dependent and sinks to the lower equatorial region of the lens capsule.
At this point, the lens capsule becomes thin and fragile, and may rupture spontaneously. If rupture occurs, liquefied proteins leak into the anterior chamber, causing the following:
This is a surgical technique reported to prevent posterior capsule rupture in Morgagnian cataract. An intraocular lens is pre-positioned as a “scaffold” to support the lax posterior capsule, reducing the risk of posterior capsule rupture during nuclear emulsification. Technical details have been modified by individual surgeons, and it has been reported to potentially improve the posterior capsule preservation rate. Reports are mainly based on small case series, and further validation is needed to establish it as a standard procedure.
Femtosecond laser-assisted cataract surgery is a technique that automates anterior capsulotomy, nuclear fragmentation, and incision creation using a laser, and is being introduced in routine cataract surgery. Regarding its application to Morgagnian cataract, the feasibility of applying it to a fibrotic anterior capsule is under investigation. The lack of red reflex and nuclear sinking may affect laser irradiation planning, and it is not currently a standard indication.
Parkash RO, Mahajan S, Parkash TO, Nayak V. Intraocular lens scaffold technique to prevent posterior capsule rupture in cases of Morgagnian cataract. J Cataract Refract Surg. 2017;43(1):8-11. PMID: 28317682.
Parkash RO, Gurnani B, Kaur K, Parkash TO, Vajpayee RB, Baldev V. Novel nucleus management technique in hypermature morgagnian cataracts with liquified cortex during phacoemulsification. Eur J Ophthalmol. 2023;33(4):1750-1754. PMID: 36811620.
Bardoloi N, Sarkar S, Burgute PS, Ghosh D, Deb AK. Capsular tension ring assisted phacoemulsification of morgagnian cataract. Indian J Ophthalmol. 2021;69(7):1781-1785. PMID: 34146028.
Dhingra D, Grover S, Kapatia G, Pandav SS, Kaushik S. Phacolytic glaucoma: A nearly forgotten entity. Eur J Ophthalmol. 2020;30(5):NP32-NP35. PMID: 30950286.
LoBue SA, Rizzuti AE, Martin CR, Albear SA, Gill ES, Shelby CL, Coleman WT 3rd, Smith EF. Preventing the Argentinian flag sign and managing anterior capsular tears: A review. Indian J Ophthalmol. 2024;72(2):162-173. PMID: 38273682.
