Lens-induced glaucoma is a secondary glaucoma in which abnormal lens position, volume changes, or protein leakage cause an increase in intraocular pressure. It is classified into angle-closure type and open-angle type based on the mechanism of angle closure1)2).
Cases in which the lens is the direct cause of angle closure account for approximately 5% of all angle-closure glaucomas1). Specific examples include intumescent cataract and anterior displacement due to lens subluxation1).
This condition is classified into the following five types:
1. Lens-Induced Secondary Angle-Closure Glaucoma
Phacomorphic glaucoma: lens swelling due to progression of cataract
Glaucoma due to lens displacement: subluxation or dislocation of the lens
2. Lens-Induced Secondary Open-Angle Glaucoma
Phacolytic glaucoma: Protein leakage from hypermature cataract
Lens-particle glaucoma: Dispersal of lens material after surgery or trauma
Phacoantigenic glaucoma: Immune reaction to lens proteins
QWhat is the difference between phacomorphic glaucoma and phacoantigenic glaucoma?
A
Phacomorphic glaucoma is an angle-closure type in which the lens swells due to progression of cataract, pushing the iris forward and causing angle closure. In contrast, phacoantigenic glaucoma is an open-angle type in which, after the lens capsule is damaged by surgery or trauma, a granulomatous inflammatory reaction to lens proteins obstructs the trabecular meshwork. In the former, the physical size of the lens is the problem; in the latter, an immune reaction is the cause.
The main subjective symptoms of lens-induced glaucoma are sudden eye pain, decreased vision, and redness 2). In the angle-closure type, nausea, vomiting, and headache may occur, similar to acute glaucoma attack 3). In the open-angle type, blurred vision and photophobia are also observed 2).
Lens-induced glaucoma with lens swelling: The affected eye shows mature cataract and shallow anterior chamber. The contralateral eye often has normal anterior chamber depth, which is an important distinguishing feature from primary angle-closure glaucoma.
Phacolytic glaucoma: The anterior chamber is deep, accompanied by hypermature cataract. Scintillating opacity is observed in the anterior chamber. The absence of keratic precipitates (KP) is important for differentiation from lens antigenic glaucoma. Pseudohypopyon (layered lens protein in the inferior anterior chamber) may also be present.
Lens cortex glaucoma: Occurs after cataract surgery, trauma, or YAG laser posterior capsulotomy. It is characterized by relatively large white particles floating in the anterior chamber. Onset is often days to weeks after the trigger, but may occur months later.
Lens antigenic glaucoma: Presents with ciliary injection, mutton-fat KP, and anterior chamber cells/flare. It often develops 1 to 14 days after surgery or trauma. It shows findings of persistent granulomatous anterior uveitis.
Lens intumescence: As cataract progresses, the lens becomes liquefied and swollen, increasing its anteroposterior diameter. This mechanically displaces the iris forward, causing pupillary block2).
Lens dislocation: Pupillary block due to subluxated or dislocated lens or prolapsed vitreous increases intraocular pressure. In traumatic dislocation, angle damage may also be involved.
Spherophakia: The lens thickness increases, causing pupillary block. Zonular weakness also contributes to angle closure due to forward displacement.
Causes of open-angle type
Phacolytic: Spontaneous capsular rupture of a hypermature cataract leads to leakage of lens material 1). Macrophages that phagocytose lens cortex and high-molecular-weight soluble proteins obstruct the trabecular meshwork1).
Retained lens material: After cataract surgery or trauma, lens material may be released and obstruct the trabecular meshwork1). The rise in intraocular pressure is proportional to the amount of retained lens fragments.
Phacoanaphylaxis: Granulomatous inflammation due to type III allergy (Arthus immune complex reaction) to lens proteins obstructs the trabecular meshwork1).
Hereditary diseases causing lens dislocation include Marfan syndrome (superotemporal dislocation), homocystinuria (inferior dislocation), and Weil-Marchesani syndrome (inferior dislocation with spherophakia). All are caused by zonular abnormalities, and subluxation or dislocation of the lens increases the risk of secondary angle-closure glaucoma4). Recessive mutations in the ADAMTSL4 gene have been identified as a cause of sporadic ectopia lentis; ADAMTSL4 promotes fibrillin-1 microfibril biogenesis and is involved in zonule formation 6).
QWhy does lens dislocation occur in Marfan syndrome?
A
Marfan syndrome is caused by mutations in the FBN1 gene (encoding fibrillin-1). Fibrillin-1 is a major structural protein of the zonules; mutations weaken and rupture the zonules, leading to lens dislocation. In Marfan syndrome, dislocation is typically superotemporal. Anterior dislocation of the lens can cause pupillary block and secondary angle-closure glaucoma.
Assess lens status (intumescence, hypermaturity, dislocation), anterior chamber depth, cells and flare in the anterior chamber, and presence of keratic precipitates 2). Evaluation of peripheral anterior chamber depth by the van Herick method is useful for screening angle closure 2).
This examination is essential for differentiating between angle-closure and open-angle types 2). In phacomorphic glaucoma, extensive angle closure is observed. In the open-angle type, the angle is open, but deposits of lens material or macrophages may be seen on the trabecular meshwork.
Anterior segment OCT and ultrasound biomicroscopy (UBM) are useful for detailed assessment of the lens and angle status 3). In phacomorphic glaucoma, the mass effect of the lens on the iris can be confirmed, and in spherophakia, lens shape abnormalities can be evaluated. In posterior lens dislocation, B-mode ultrasound can detect the dislocated lens.
In differentiating phacomorphic glaucoma from primary angle-closure glaucoma, the presence of a swollen cataract, the anterior chamber depth of the contralateral eye (normal in phacomorphic, shallow in primary angle closure), and the presence of cells and flare in the anterior chamber are important distinguishing points.
Initial treatment: Administer cycloplegic drugs (atropine) eye drops to move the lens backward and relieve pupillary block. Lower intraocular pressure with beta-blockers, carbonic anhydrase inhibitors, and hyperosmotic agents.
Miotics are contraindicated: They contract the ciliary muscle, relax the zonules of Zinn, and promote forward movement of the lens, so they must not be used 3).
Laser iridotomy: Performed when intraocular pressure is poorly controlled with medication. Prophylactically performed on the fellow eye if there is a predisposition to angle closure 3).
Definitive surgery: Lens extraction is the curative treatment. For intumescent cataract, perform phacoemulsification and intraocular lens implantation. For spherophakia, intracapsular lens extraction is required.
Treatment of Open-Angle Glaucoma
Medical therapy: Use steroid eye drops and cycloplegics to reduce inflammation, and aqueous humor suppressants to lower intraocular pressure1).
Phacolytic glaucoma: Removal of the lens (cataract surgery) is essential.
Lens particle glaucoma: If anti-inflammatory and intraocular pressure-lowering drugs are ineffective, perform anterior chamber irrigation to completely remove residual lens particles.
Phacoantigenic glaucoma: If anti-inflammatory and intraocular pressure-lowering drugs are ineffective, surgically remove residual lens material. Perform vitrectomy if necessary 1).
QWhy are miotics contraindicated in lens-induced glaucoma?
A
In angle-closure lens-induced glaucoma, miotics contract the ciliary muscle, relaxing the zonules of Zinn and causing the lens to move further forward, worsening pupillary block. Conversely, cycloplegics (e.g., atropine) relax the ciliary muscle, tightening the zonules and moving the lens backward, helping to relieve pupillary block.
In lens-induced angle-closure glaucoma, changes in the position or volume of the lens cause angle closure 2)3).
Mechanism due to lens swelling: As cataracts progress, the lens cortex liquefies and the lens swells. The increase in anteroposterior diameter mechanically pushes the iris forward, and relative pupillary block also contributes to angle-closure glaucoma2). Age-related cases gradually close the angle, but in young or traumatic cases, it progresses rapidly.
Mechanism due to lens displacement: Pupillary block from a dislocated lens or prolapsed vitreous causes angle-closure glaucoma. In posterior dislocation of the lens (fall into the vitreous), pupillary block by the vitreous can cause a rapid rise in intraocular pressure. Forward movement of the lens-iris diaphragm leads to angle closure and increased intraocular pressure3).
In lens-induced open-angle glaucoma, the trabecular outflow pathway is obstructed by lens particles and/or inflammatory cells 1).
Phacolytic glaucoma: Lens material leaks through the capsule from a mature or hypermature cataract1). Macrophages that have phagocytosed lens cortex are the main mechanism obstructing the trabecular meshwork, but high-molecular-weight soluble proteins themselves can also cause obstruction. In phacolytic glaucoma, macrophages that have phagocytosed lens material are present in the anterior chamber and block the trabecular meshwork.
Phacoantigenic glaucoma: After damage to the lens capsule from surgery or trauma, a type III allergic reaction (Arthus-type immune complex reaction) to lens proteins causes granulomatous inflammation 1). Pathologically, macrophages and neutrophils accumulate in the residual lens cortex, and if inflammation persists, a cyclitic membrane forms.
In familial lens ectopia, dislocation of the intraocular lens is a recurrent complication. Wilczyński et al. reported scleral fixation using a sutureless Carlevale lens for recurrent intraocular lens dislocation in a 36-year-old patient with familial lens ectopia 4). In young patients, zonular weakness is a long-term problem, so sutureless fixation is expected to reduce postoperative complications 4).
Kalra et al. performed cataract surgery using a portable femtosecond laser under general anesthesia in a 13-year-old child with spherophakia and lens ectopia 5). The femtosecond laser can create a precise capsulotomy without excessive traction on the fragile zonules, resulting in high capsular preservation rates 5). This may be a useful technique for cataract surgery in children with lens ectopia.
Gustafson et al. reported that recessive mutations in the ADAMTSL4 gene cause craniosynostosis and ectopia lentis6). ADAMTSL4 is a protein that promotes the biosynthesis of fibrillin-1 microfibrils, and its loss of function is proposed to simultaneously cause disruption of the zonules of Zinn (ectopia lentis) and abnormalities in the TGFβ signaling pathway (craniosynostosis) 6). Elucidation of the molecular mechanisms of ectopia lentis may contribute to the development of future gene therapies.
QWhat is the prognosis for lens-induced glaucoma?
A
If the lens is removed at the appropriate time, good intraocular pressure control can be achieved in many cases. However, if glaucomatous optic neuropathy has progressed due to long-term high intraocular pressure or inflammation, recovery of visual function is difficult. Phacolytic glaucoma and phacomorphic glaucoma are considered to have a relatively good prognosis, but hereditary diseases with ectopia lentis may require repeated surgeries.
European Glaucoma Society. Terminology and Guidelines for Glaucoma, 6th Edition. PubliComm; 2025.
日本緑内障学会. 緑内障診療ガイドライン(第5版). 日眼会誌. 2022;126:85-177.
European Glaucoma Society. Terminology and Guidelines for Glaucoma, 5th Edition. PubliComm; 2021.
Wilczyński TK, Niewiem A, Leszczyński R, Michalska-Malecka K. Recurrent Intraocular Lens Dislocation in a Patient with Familial Ectopia Lentis. Int J Environ Res Public Health. 2021;18(9):4545.
Kalra N, Agarwal R, Agarwal T, Sinha R. Portable femtosecond laser assisted cataract surgery in a child with bilateral ectopia lentis with microspherophakia. Am J Ophthalmol Case Rep. 2022;26:101442.
Gustafson JA, Bjork M, van Ravenswaaij-Arts CMA, Cunningham ML. Mechanism of Disease: Recessive ADAMTSL4 Mutations and Craniosynostosis with Ectopia Lentis. Case Rep Genet. 2022;2022:3239260.
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