Secondary Intraocular Lens Implantation

Key Points at a Glance

Key Points of This Condition

• Secondary IOL implantation is an IOL transplantation procedure performed separately from the initial surgery for conditions such as aphakia, IOL dislocation, IOL opacification, and refractive error.
• The choice of surgical technique is determined based on the condition of the remaining lens capsule, ciliary sulcus, and iris tissue, as well as the surgeon’s experience.
• If capsular support is sufficient, ciliary sulcus fixation (3-piece IOL) is the first choice.
• If capsular support is absent, the main options are scleral fixation (suture method or Yamane technique) or iris-claw IOL.
• There is no significant difference in final visual acuity among the techniques; the choice is made after understanding the specific risks of each technique.
• In traumatic aphakia, primary IOL insertion is avoided to reduce infection risk, and secondary insertion is recommended.

1. What is Secondary Intraocular Lens Implantation?

Secondary intraocular lens (IOL) implantation is a general term for additional IOL transplantation performed for aphakia occurring during or after initial cataract surgery, or for problems with an existing IOL.

Main Indications

• Aphakic eye: When IOL could not be inserted due to complications, trauma, or congenital anomalies during initial surgery
• IOL dislocation/subluxation: IOL displacement or drop due to zonular rupture or suture breakage
• IOL opacification: Calcification of hydrophilic acrylic IOL, etc.
• Refractive surprise: Unexpected large refractive error
• Patient dissatisfaction with multifocal IOL: When glare or halos interfere with daily life
• IOL-induced corneal endothelial failure or cystoid macular edema: Chronic inflammation due to poor IOL position
• After pediatric congenital cataract surgery: Optical rehabilitation after extraction before 1-2 years of age

In open globe injury (OGI), primary IOL implantation increases the risk of endophthalmitis, so secondary implantation is recommended ¹⁾.

Q What is the difference between IOL exchange and secondary IOL implantation?

A

IOL exchange refers to the procedure of removing the existing IOL and inserting a new one. Secondary IOL implantation is a broader concept that includes new implantation in aphakic eyes without an existing IOL. This article covers both.

2. Main symptoms and clinical findings

Subjective symptoms

• Decreased visual acuity: due to focal disturbance from IOL dislocation, decentration, or opacification
• Monocular diplopia and glare: due to IOL tilt or decentration
• Aniseikonia and eye strain: due to high hyperopia in aphakia or anisometropia
• Photophobia and halos: due to IOL opacification or optical issues with multifocal IOLs

Clinical findings

IOL dislocation

IOL decentration: The haptic is visible in the pupillary area under mydriasis.

Iridodonesis: A sign of zonular laxity.

Vitreous prolapse: May be accompanied by vitreous herniation into the anterior chamber.

IOL opacification

Calcification: Common in hydrophilic acrylic IOLs. Occurs after contact with intraocular gas or air.

Posterior capsule opacification: Visual loss due to posterior capsule opacification (can be treated with Nd:YAG laser).

Deposits on IOL surface: Changes due to inflammation or infection.

3. Preoperative Evaluation

Essential Examinations

Preoperative evaluation for secondary IOL implantation requires more detailed anterior segment assessment than routine cataract surgery.

• Assessment of conjunctival and scleral condition: Including presence of glaucoma drainage devices
• Corneal evaluation: Clarity, edema, pachymetry, specular microscopy (corneal endothelial cell count)
• Evaluation of anterior chamber depth and vitreous prolapse
• Residual iris and capsular status: Key to surgical technique selection
• Assessment of existing IOL subluxation degree and IOL type
• Posterior segment evaluation: Identification of fundus pathology that may limit postoperative visual acuity
• Anterior segment OCT: Precise evaluation of IOL position and anterior chamber depth

Q When is secondary IOL implantation performed?

A

Secondary IOL implantation after trauma is performed after confirming resolution of infection risk and inflammation. After open globe injury, a waiting period of at least several months may be recommended ¹⁾. For secondary implantation after intraoperative complications during cataract surgery, the optimal timing may be within 2–6 weeks postoperatively, before closure of the anterior capsule. In a survey of 481 ophthalmologists in India, 2–6 weeks was the most common response ³⁾.

4. Diagnosis and Examination Methods

Algorithm for Determining Surgical Procedure

The choice of surgical procedure is based on the following stepwise evaluation.

1. If the capsular bag is completely intact: Release adhesions between the anterior and posterior capsules and attempt in-the-bag fixation.
2. If the continuous curvilinear capsulorhexis (CCC) edge is intact circumferentially: Three-piece IOL fixation in the ciliary sulcus (± optic capture).
3. If the capsular bag is partially or incompletely present: Choose ciliary sulcus fixation, iris fixation, or scleral fixation depending on the capsular condition.
4. If there is no capsular bag: Scleral fixation or iris-claw IOL.

5. Standard Treatment Methods

Three-Piece IOL Fixation in the Ciliary Sulcus

This is indicated when the edge of the continuous curvilinear capsulorhexis is intact circumferentially. A three-piece acrylic IOL is used for sulcus fixation (one-piece acrylic IOL sulcus fixation should be avoided as it often leads to IOL dislocation, elevated intraocular pressure, and glaucoma).

Optic capture combined with sulcus fixation improves IOL stability and centration, and reduces myopic shift. The best method is to place the haptics in the ciliary sulcus and capture the optic through the continuous curvilinear capsulorhexis.

In ciliary sulcus fixation, the IOL is positioned more anteriorly than in-the-bag fixation, so the IOL power must be appropriately reduced to avoid myopic shift.

Iris-Claw IOL (Artisan IOL)

This is one option for eyes without capsular support. It can be fixed to the anterior surface (anterior chamber side) or posterior surface (retropupillary fixation) of the iris.

Advantages of retropupillary iris-claw fixation:

• Placement in the physiological posterior chamber
• Deeper anterior chamber than anterior fixation, lower risk of corneal endothelial failure
• Earlier and better visual recovery than anterior fixation

Requirements for implantation:

• Complete removal of vitreous from the anterior chamber
• At least 270 degrees of remaining iris tissue (pupil diameter <6 mm)
• Anterior chamber depth ≥3 mm
• Peripheral iridectomy (PI) required to prevent pupillary block

Complications of iris-claw IOL: Corneal endothelial cell loss (approximately 10.9% at 3 years postoperatively), increased intraocular pressure (0–7%), pupil ovalization (up to 13.9%), IOL dislocation (0–10%)

Comparison item	Retroiridal fixation	Scleral-fixated IOL
Surgical time	Short	Long
Visual acuity (BCVA)	No significant difference	No significant difference
Specific complications	Iris atrophy, pigment dispersion, pupil distortion	Suture exposure, IOL tilt

Scleral fixation

It is selected in patients with insufficient capsular or iris support, or in those with shallow anterior chamber or corneal endothelial failure.

Suture fixation

• Ab externo method (Lewis method): The suture is passed from outside the eye to inside. Highly reliable.
• Ab interno method: Passed from inside the eye to outside. Slightly higher risk of complications due to blind manipulation.
• Suture materials: 9-0 polypropylene, 7-0 Gore-Tex (CV-8), or 6-0 polypropylene
• Knot management: Cover the knot with a triangular scleral flap, Hoffman pocket, Z-suture, etc., to prevent infection

Yamane method (sutureless intrascleral fixation)

The Yamane method is currently a rapidly popularizing technique for secondary IOL insertion in eyes without capsular support. Its effectiveness has been reported in various situations, including aphakia after open globe injury¹⁾.

• Transconjunctival approach using a 30G (or 27G) needle eliminates the need for conjunctival incision.
• The tip of the haptic of a three-piece IOL is heat-treated to create a flange, which is then fixed within a scleral tunnel.
• No risk of suture breakage or exposure.
• Low risk of postoperative hypotony (due to small 30G or 27G incisions).

In a case of aphakia secondary to open-globe injury, the Yamane technique achieved improvement to uncorrected visual acuity of 20/50 at 15 months postoperatively (with diabetic macular edema as a limiting factor for residual vision) ¹⁾.

Sutured vs. Sutureless

There is no definitive study showing which is superior. Vitreoretinal surgeons tend to prefer sutureless scleral-fixated IOLs (57%), while anterior segment surgeons tend to prefer sutured IOLs (60%). Among sutureless techniques, vitreoretinal surgeons favor the Yamane method (40%), and anterior segment surgeons favor glued IOLs (49%) ³⁾.

Precautions for Secondary IOL Implantation

• Extracapsular fixation of one-piece acrylic IOLs is contraindicated: it leads to a high rate of IOL dislocation, elevated intraocular pressure, and secondary glaucoma.
• Hydrophilic acrylic IOLs (e.g., Akreos) are unsuitable for patients who may require future vitreous surgery: exposure to intraocular gas or air can cause calcification.
• Evaluation of corneal endothelial cells: consider further endothelial cell loss due to surgical manipulation.
• IOL power for ciliary sulcus fixation: subtract appropriately because the IOL is positioned more anteriorly than in-the-bag fixation.

6. Pathophysiology and Detailed Mechanisms

Mechanisms of Late IOL Dislocation

Progressive zonular laxity due to pseudoexfoliation syndrome, trauma, high myopia, or connective tissue disease is the most common cause. In suture-fixated IOLs, gradual hydrolysis and oxidative degradation of polypropylene sutures (especially 10-0) lead to suture breakage. Breakage rates of 12–28% have been reported for 10-0 polypropylene within 50–80 months, and a switch to 9-0 is recommended.

Significance of In-the-Bag Fixation

In aphakic eyes with a completely intact lens capsule, Soemmering’s ring and proliferating lens epithelial cells help maintain the space between the anterior and posterior capsules. By incising this space with an MVR knife, removing residual cortex, and then inserting the IOL into the capsular bag, fixation in a physiological position becomes possible.

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7. Latest Research and Future Prospects (Investigational Reports)

For Patients: Please Read Carefully

The following content is currently under investigation or in clinical trials and is not standard treatment available at general hospitals. It is reference information for professionals regarding future medical developments.

Scleral Fixation of EDOF Lens (Carlevale FIL SSF EVOLVE)

The Carlevale IOL (FIL SSF) is a new sutureless scleral-fixated IOL design with T-shaped haptics that pass through scleral incisions. Cases using the EDOF (extended depth of focus) version (FIL SSF EVOLVE) in aphakic eyes have been reported, achieving UDVA 20/23 (distance) and UNVA 20/40 (30 cm near) at 3 months postoperatively ²⁾. The combination of EDOF optics and scleral fixation design may offer spectacle independence for patients without capsular support, but long-term outcomes are still being accumulated.

Saloon Door Technique (Artificial Iris-Sparing IOL Exchange)

The “Saloon Door Technique” has been reported, in which an IOL is fixated behind an existing artificial iris (AI) without removing it. The AI is radially incised at the 12 and 6 o’clock positions, a 3-piece IOL is passed through this “door-like opening” into the posterior chamber, and then scleral-fixated using the Yamane technique ⁴⁾. This avoids AI removal and refixation, reducing surgical invasiveness, but it involves off-label use (incision) of the AI, and long-term safety assessment of AI structure is needed.

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8. References

1. Thomas J, Armstrong G. Use of Yamane technique for secondary intraocular lens implantation following open globe injury. BMJ Case Rep. 2023;16:e255995.
2. Petrou P, Doumazos S, Kandarakis SA, et al. Implantation of a scleral fixated (Carlevale) EDOF IOL in aphakia. Am J Ophthalmol Case Rep. 2025;39:102391.
3. Kelkar AS, Kelkar J, Bhende P, et al. Preferred practice patterns in aphakia management in adults in India: A survey. Indian J Ophthalmol. 2022;70:2855-2860.
4. Roth K, Seiller-Tarbuk K, Amon M. Saloon Door Technique - “open sky” IOL exchange utilising flanged haptic fixation behind a pre-existing Artificial Iris. Am J Ophthalmol Case Rep. 2025;40:102431.