What are the considerations for intraocular lens (IOL) selection in patients with retinitis pigmentosa (RP)?

Intraocular Lens Considerations for Patients with Retinitis Pigmentosa

In patients with retinitis pigmentosa (RP) undergoing cataract surgery, use hydrophobic acrylic IOLs to minimize posterior capsule opacification (PCO), avoid multifocal IOLs due to compromised retinal function, and consider enlarged optic (7.0 mm) monofocal IOLs or hybrid monovision strategies to maximize remaining visual field and quality of life. 1, 2

IOL Material Selection: Critical for PCO Prevention

The single most important consideration is IOL biomaterial choice, as RP patients have dramatically elevated PCO rates approaching 100% at six months with certain materials 1:

• Hydrophobic acrylic IOLs are strongly preferred, with PCO rates of only 41.38% at 12 months compared to 89.9% for PMMA and 90.95% for silicone IOLs 1
• Hydrophilic acrylic materials show intermediate PCO rates of 60% and should be avoided 1
• The smooth surface of hydrophobic acrylic material prevents epithelial growth and fibrosis toward the visual axis 1
• Plan for aggressive YAG capsulotomy follow-up regardless of IOL choice, as PCO remains highly prevalent even with optimal materials 3, 1

Optical Design Considerations

Avoid Premium IOLs in Most Cases

• Standard monofocal IOLs are generally preferred over multifocal or extended depth-of-focus designs 3
• RP patients have compromised photoreceptor function, progressive visual field loss, and increased intraocular light scatter that makes them poor candidates for diffractive optics 4
• Patients with RP demonstrate straylight parameters elevated 2.5 to 5 times normal even without significant lens opacities, which would be exacerbated by multifocal designs 4

Consider Enlarged Optic IOLs

• 7.0 mm optic IOLs (such as ASPIRA-aXA) can be beneficial for maximizing light transmission through the remaining functional retina in patients with tunnel vision 2
• The larger optic zone allows better utilization of the constricted visual field characteristic of RP 2
• Case evidence demonstrates improvement from hand motion to 0.3 logMAR with enlarged optic IOLs in advanced RP 2

Hybrid Monovision Strategy

For select patients with bilateral cataracts and adequate counseling:

• Implant a high-add IOL (e.g., LENTIS MAX LS-313 MF80) in the near-dominant eye and an enlarged optic monofocal in the distance-dominant eye 2
• This approach improved both distance (0.5 logMAR) and near vision (0.4 logMAR) with significant quality of life enhancement in documented cases 2
• This strategy is only appropriate for motivated patients with realistic expectations who understand the progressive nature of RP 2

Surgical Technique Modifications

Minimize Phototoxic Damage

• Reduce microscope light intensity and duration of exposure during surgery, as RP retinas are more vulnerable to phototoxic damage 3
• Use shorter surgical times when possible and consider protective filters 3

Capsular Management

• Perform meticulous capsulorrhexis with complete cortical cleanup to minimize PCO substrate 3, 1
• Consider prophylactic posterior capsulotomy in select cases, though this increases other complication risks 3
• Ensure IOL is well-centered in the capsular bag, as aspheric IOLs are less tolerant of decentration 5

Avoid Aspheric IOLs in Zonulopathy

• Standard spherical IOLs may be preferable if zonular weakness is present, as aspheric designs are less tolerant of tilt and decentration 5
• RP can be associated with zonular abnormalities that increase dislocation risk 3

Postoperative Complication Monitoring

RP patients have significantly higher complication rates than standard cataract patients 3:

• Monitor closely for cystoid macular edema (CME), which occurs more frequently in RP patients and can devastate remaining central vision 3
• Watch for capsular contraction syndrome, which is more common in RP 3
• Monitor IOP elevation, as postoperative pressure spikes occur more frequently 3
• Assess for IOL dislocation at each follow-up due to potential zonular weakness 3

Preoperative Counseling Essentials

• Set realistic expectations: Visual improvement may be modest given underlying retinal disease 6
• Explain that cataract removal addresses only the lens opacity, not the progressive retinal degeneration 3, 6
• Discuss the high likelihood of requiring YAG capsulotomy within the first year 1
• When properly counseled, patient satisfaction rates are high (15 of 16 patients in one series) despite limited visual gains 6

Biometry Considerations

• Use standard biometry formulas (Barrett Universal II, Kane, or Haigis) with careful attention to axial length measurement 5
• RP patients are often myopic; ensure lens constants are optimized for higher minus-power IOLs if applicable 5
• Consider intraoperative aberrometry if available to confirm IOL power selection 5