Lens dislocation

Disease Description (Causes and Symptoms)

Lens luxation (ectopia lentis, lens luxation) is a condition in which the lens moves out of its original position because the ciliary zonules (suspensory ligaments of the lens, zonules) that support the lens are damaged or weakened. Common causes include:

• Genetic systemic diseases: Marfan syndrome, Ehlers-Danlos syndrome, Weill-Marchesani syndrome, homocystinemia (e.g., homocystinuria), and others.
• Trauma: rupture of the zonules caused by a blow or impact.
• Rarely, age-related or inflammatory changes, or occurrence after surgery.

Pathophysiology: When the zonules weaken, the abnormal position of the lens changes refraction, and structures around the pupil (e.g., the iris) become unstable, causing decreased vision, glare, and double vision. If the lens dislocates into the anterior chamber, the risk of corneal endothelial damage or angle-closure glaucoma increases, and the situation may become an emergency.

Main Symptoms

• Visual disturbance (blurred vision, diplopia, or optical distortion)
• Iris trembling (iridodonesis; phacodonesis)
• Glare and photophobia caused by a change in pupil position
• In acute anterior dislocation: pain, redness, sudden decrease in vision, and increased intraocular pressure

Diagnostic findings: After dilation, observe the abnormal position of the lens with a slit lamp; perform light examination and intraocular pressure measurement; and, when indicated, perform ultrasonography (UBM, B-scan), refraction, and retinal examination. If the condition is bilateral or occurs at a young age, genetic testing and cardiovascular evaluation (including for aortic aneurysm) are recommended.

Treatment Methods

The goals of treatment are to restore vision, prevent and treat complications, and prevent secondary damage (glaucoma, corneal damage, retinal detachment, etc.).

Non-surgical Treatment

• Refractive correction: Apply glasses or contact lenses first when correction is possible.
• Observation: If the dislocation is partial and symptoms are mild, conduct regular monitoring (visual acuity, intraocular pressure, and retinal examination).
• Emergency response: If the lens is in the anterior chamber and contact with the corneal endothelium or an acute rise in intraocular pressure is suspected, immediate ophthalmology care is necessary (emergency measures and surgery may be considered).

Surgical Treatment

• Indications: Severe decrease in vision, accompanying cataract, recurrent dislocation or anterior dislocation, or risk of glaucoma or corneal damage.
• Surgical methods: Lens removal (selection of anterior or posterior capsular approach depends on the situation); vitrectomy when necessary (in cases of posterior dislocation); and selection of a method for inserting an intraocular lens (IOL), such as a scleral-fixated IOL, iris-fixated IOL, intrascleral fixation, or anterior chamber IOL. The surgical method is determined according to the location and extent of the dislocation, accompanying lesions, and ocular structure.
• Considering the risk of complications during surgery, the procedure should be performed by an experienced ophthalmologist (a retinal or anterior-segment specialist).

Medication (Adjunctive)

• Pain and inflammation control: Topical steroids and nonsteroidal anti-inflammatory drugs (as directed by a physician).
• Intraocular pressure control: If glaucoma develops, eye drops or oral medication may be needed. (The specific choice of medication is determined by a specialist according to the patient’s condition.)

Precautions and Self-Care

• Prevent trauma: Wear protective eyewear during sports and work.
• Do not rub the eyes or apply strong pressure to them.
• Regular follow-up examinations (visual acuity, intraocular pressure, and retinal status) are essential.
• If a genetic cause is suspected, assessment of family history and, when necessary, genetic counseling and cardiovascular evaluation are recommended.

Complications

• Secondary glaucoma (caused by angle closure or secondary corneal damage), corneal endothelial damage, cataract, retinal detachment, chronic inflammation, permanent decrease in vision, and others.

Prognosis

• Damage to the zonules usually does not recover spontaneously. The prognosis varies depending on the extent of the dislocation, accompanying complications, and the timing and method of treatment. With treatment at an appropriate time and by an appropriate method, the likelihood of visual recovery is high. If anterior dislocation causes corneal or intraocular pressure problems, urgent treatment is required, and the visual prognosis may be worse.

Checklist Before an Outpatient Visit (Including Sample Questions)

Items and Information to Prepare

• A list of medications currently being taken (including prescription drugs, over-the-counter drugs, and supplements)
• History of previous ophthalmic surgery or trauma and when it occurred
• When the symptoms began and how they have changed (whether they appeared suddenly or gradually, whether one or both eyes are affected, etc.)
• Record of changes in vision (previous visual acuity test results, if available)
• Details of symptoms such as eye pain, redness, glare, double vision, and photophobia
• Family history (especially Marfan syndrome, connective tissue disease, and vascular disease)
• Bring any recent test results, if available (intraocular pressure, visual acuity chart, ultrasonography, etc.)

Examples of What the Doctor May Ask During the Visit

• When did the symptoms begin? How quickly have they progressed?
• Has your eye recently been struck or injured?
• Does anyone in your family have similar eye problems or connective tissue disease?
• Are you currently using any eye drops or systemic medications?

General Examples of Questions to Ask the Doctor

• “In my case, does my current condition definitely require treatment, or is observation sufficient?”
• “If surgery is needed, which surgical method do you recommend? What are the risks, and how much visual recovery can be expected?”
• “What should I be careful about to prevent complications such as glaucoma or retinal detachment?”
• “A genetic cause is suspected. Will additional testing or family testing be necessary?”

Examples of Disease-Specific Questions

• “The lens has moved into the anterior chamber and is affecting the cornea or intraocular pressure. Is this a situation requiring emergency treatment right now?”
• “During surgery, how will the intraocular lens be inserted (what stable fixation method will be used), and what are the advantages and disadvantages?”