**6. Advanced technology IOL selection strategy**

When the patient and ocular conditions had been fully evaluated, the surgeon can match the right advanced technology IOL to the right patients that can ensure positive outcomes. Here we present a premium IOLs decision flowchart based on the detail recommendations mentioned above.

	- A strong desire to be independent with spectacle for near, intermediate, far distance
	- A positive attitude and leading an active life, not a perfectionist
	- A job not to require activity at night or low-light condition
	- Preoperative visual acuity and refractive error
		- i.Hyperopic, high myopia and plano presbyopia are good candidates for presbyopia correcting IOL surgery.

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• IOLs solutions

*Successful Premium Multifocal IOL Surgery: Key Issues and Pearls*

ii.Mild myopia with presbyopia patients are typically accustomed to removing their glasses at near, so it is important to set proper expectations

iii.Thorough education and careful counsel are needed for mild myopic

ii.Corneal astigmatism or aberration measurement by using multi-device

i.photopic pupil size of 3.5 mm or less and mesopic pupil size of

ii. angle Kappa greater than half of the diameter of the central optical zone

1.Optical biometry is recommended, which included partial poherence interferometry (PCI) IOLMaster 500, optical low coherence reflectometry Lenstar

○ Emmetropia Verifying Optical (EVO), Kane, Næser 2, Olsen, the

Monofocal aspheric IOLs is most common IOLs in modern phacoemulsification surgery which can neutralize the residual corneal spherical aberration and improve contrast sensitivity especially in dim light condition. For the patients with

Panacea, Pearl DGS, Radial Basis Function (RBF), T2 and VRF formulas

patients before presbyopia correcting IOLs surgery.

i.Dry eye or OSD evaluation and management

iii.Address the posterior surface corneal astigmatism

iv.Consider surgical induced astigmatism

i.Post-corneal refractive surgery

• Biometry measurement and IOL calculation

900 and SWEPT source OCT IOLMaster 700

○ Haigis, Hoffer Q, Holladay 1 and 2 and SRK/T.

3.Special attention to post-refractive surgery IOL calculation issue

2. 3rd and new generation formulal: [61]

○ Barrett Universal II formula

*DOI: http://dx.doi.org/10.5772/intechopen.96182*

○ Corneal conditions

○ Pupil size and centration

5 mm or less

○ Comorbidities

ii.Glaucoma

iii.Retinal disease


*Current Cataract Surgical Techniques*

the premium IOLs power calculation [55].

patients the rule with multifocal lenses.

**6. Advanced technology IOL selection strategy**

the detail recommendations mentioned above.

• Patients selection:

distance

• Ocular Feature Checklist

pathology like epiretinal membrane or cystoid macular edema which is influenced

power calculator can provide greater refractive predictability [60].

Cataract surgeon must personalize his IOL constants for premium lenses. Although the design of the IOL is the primary factor in the constant, variations in surgical technique such as the placement of the IOL, the location and design of the incision, and differences in biometry and technicians also affect the personalized lens constant. Preoperative biometric data and post-operative refractive error of 20 to 40 cases should be collected in order to personalize lens constant [52]. This process is the only way to achieve superior results with these IOLs and accuracy to within ±0.25 D for 95 percent of patients. Personalizing the lens constant is critical to eliminating the systematic variations that make excellent results and happy

When the patient and ocular conditions had been fully evaluated, the surgeon can match the right advanced technology IOL to the right patients that can ensure positive outcomes. Here we present a premium IOLs decision flowchart based on

○ A strong desire to be independent with spectacle for near, intermediate, far

i.Hyperopic, high myopia and plano presbyopia are good candidates for

○ A positive attitude and leading an active life, not a perfectionist

○ A job not to require activity at night or low-light condition

○ Preoperative visual acuity and refractive error

presbyopia correcting IOL surgery.

Besides the accuracy biometry, the IOL power calculation formula choice also is critical for premium IOLs surgery. Though the third and newer generation formula can get accuracy refractive result in normal axis length and keratometry eyes, attention must be paid to the long axial length eye as well as the abnormal corneal power cases [56]. New IOL power calculation formula like Barrett, Hill-RBF and Olsen will achieve more precision and accuracy in longer and short axial length eyes [57]. The IOL power calculation in post corneal refractive surgery eyes always is a challenge issue. Whether corneal radical keratotomy or PRK/LASIK always change the corneal shape of in different ways. Errors in evaluation of the correct corneal power and errors in estimating the effective lens position with the classical thin-lens formulas lead to underestimate the IOL power and hyperopic postoperative refractive surprise. Many adjustment methods had been developed to estimate the true corneal keratometric data such as Haigis-L formula, Shammas no-history formula [58]. The new device like schiempflug or swept source OCT which can directly measure the anterior/posterior/total corneal power to obtain more accuracy results [59]. Modern IOL formulas, such as the Barrett True-K and ascrs.org web-based IOL

**144**

	- i.photopic pupil size of 3.5 mm or less and mesopic pupil size of 5 mm or less
	- ii. angle Kappa greater than half of the diameter of the central optical zone
	- i.Post-corneal refractive surgery
	- ii.Glaucoma
	- iii.Retinal disease
	- Haigis, Hoffer Q, Holladay 1 and 2 and SRK/T.
	- Barrett Universal II formula
	- Emmetropia Verifying Optical (EVO), Kane, Næser 2, Olsen, the Panacea, Pearl DGS, Radial Basis Function (RBF), T2 and VRF formulas

Monofocal aspheric IOLs is most common IOLs in modern phacoemulsification surgery which can neutralize the residual corneal spherical aberration and improve contrast sensitivity especially in dim light condition. For the patients with

**Figure 8.**

*Flow chart for advanced technology IOL selection.*

previous corneal myopic or hyperopic correction procedure or with high concern about halo, glare and night vision, the choice of aspherical IOLs should be tailored basing on the high aberration. Monofocal aspheric IOLs can used for monovision that is a simple solution for presbyopia correcting. It provides monofocal quality of vision, and many patients have been satisfied with this option. However, some patients have reported reduced depth perception, a feeling of imbalance, and

**147**

*Successful Premium Multifocal IOL Surgery: Key Issues and Pearls*

limited intermediate vision. There are some modified strategies as mini-monovision or micro monovision which the non-dominant eye targeted for −0.75 to −1.25 D (mini-monovision) or around −0.50D (micro-monovision) of myopia to increase visual function at near and intermediate distance [62]. But monovision design may cause some potential problems such as loss of depth perception [63, 64]. A soft contact lens trial is a good predictor for simulating monovision solution, but due to cataract patients often being with worse vision, it is not always indicative of actual

Accommodating IOL is designed for allowing the IOL to move anteriorly or posteriorly, depending on the accommodative forces of the eye. It has the better contrast sensitivity and low photophobia than multifocal IOLs. However, most patients cannot achieve sufficient accommodation for functional near vision and

Multifocal IOLs by using refractive or/and diffractive optics is most popular presbyopia correcting IOLs solution in recent years. These type IOLs provide the high patient satisfaction and a better chance of spectacle independence in the refractive lens exchange procedure. Near addition powers are different in different multifocal IOLs, which is often from 1.5D to 4.0D. The higher add can offer a better near vision, but easy led to adverse effects such as dysphotopsia and a reduction in contrast sensitivity. In some aged patients, it will cost several months to neuroadapt of the multifoci images in the retina. To decide which near add power is right for a given patient, the surgeon must evaluate subjective factors (occupations, hobbies, expectations, concernabout night vision) and objective factors (preoperative visual

Extended depth of focus (EDOF) IOLs are a set of intraocular lenses that extend vision instead of offering discrete close, intermediate, or distance vision. These IOLs based on diffractive, pin-hole or aberration technique, while minimizing the quality of vision compromises and night vision symptoms that are associated with multifocal lenses. The EDOF IOLs are more tolerance higher levels of cylinder error, especially for higher amounts of astigmatism in the range of 0.75D to more than 1.0D. Due to EDOF IOLs delivers less spectacle independence than trifocal IOLs, mini-monovision is common strategy with EDOF IOLs implantation. It set the nondominant eye's target at −0.75D, which relates to an extension of the depth of focus, giving the patient the ability to read at a distance of about 45- to-50 cm, thus optimizing their potential for spectacle independence [50]. EDOF IOLs also can be considered for patients who had

Success in cataract surgery with premium IOLs lies in performing every step precisely and predictably. The surgeon team should check the patient's information,

Surgeons must pay attention to preexisting or surgically induced astigmatism, because it can have a huge impact on visual outcomes with a multifocal IOL. The magnitude of astigmatism and axis should be checked by more than two device such as topography, IOLMaster, Lenstar and so on. For less than 1.0D astigmatism, the incision at steep axis is the better approach. When preoperative astigmatism is up to1.5 diopter, the limbal relaxing incisions (LRIs) can be considerable [65]. At higher levels of astigmatism than 1.5D, the best solution is toric multifocal IOLs [66]. Whether LRI or toric IOLs, the corneal limbal mark should be made before surgery. Many manual method or device had been developed, and computerized

*DOI: http://dx.doi.org/10.5772/intechopen.96182*

visual performance after cataract surgery.

acuity and refraction error, height/arm length).

history of corneal refractive surgery [34] (**Figure 8**).

the surgical device and material availability.

automated axis marking system also can been chosen [67].

**7. Surgical techniques**

might require reading glasses.

#### *Successful Premium Multifocal IOL Surgery: Key Issues and Pearls DOI: http://dx.doi.org/10.5772/intechopen.96182*

*Current Cataract Surgical Techniques*

**146**

**Figure 8.**

*Flow chart for advanced technology IOL selection.*

previous corneal myopic or hyperopic correction procedure or with high concern about halo, glare and night vision, the choice of aspherical IOLs should be tailored basing on the high aberration. Monofocal aspheric IOLs can used for monovision that is a simple solution for presbyopia correcting. It provides monofocal quality of vision, and many patients have been satisfied with this option. However, some patients have reported reduced depth perception, a feeling of imbalance, and

limited intermediate vision. There are some modified strategies as mini-monovision or micro monovision which the non-dominant eye targeted for −0.75 to −1.25 D (mini-monovision) or around −0.50D (micro-monovision) of myopia to increase visual function at near and intermediate distance [62]. But monovision design may cause some potential problems such as loss of depth perception [63, 64]. A soft contact lens trial is a good predictor for simulating monovision solution, but due to cataract patients often being with worse vision, it is not always indicative of actual visual performance after cataract surgery.

Accommodating IOL is designed for allowing the IOL to move anteriorly or posteriorly, depending on the accommodative forces of the eye. It has the better contrast sensitivity and low photophobia than multifocal IOLs. However, most patients cannot achieve sufficient accommodation for functional near vision and might require reading glasses.

Multifocal IOLs by using refractive or/and diffractive optics is most popular presbyopia correcting IOLs solution in recent years. These type IOLs provide the high patient satisfaction and a better chance of spectacle independence in the refractive lens exchange procedure. Near addition powers are different in different multifocal IOLs, which is often from 1.5D to 4.0D. The higher add can offer a better near vision, but easy led to adverse effects such as dysphotopsia and a reduction in contrast sensitivity. In some aged patients, it will cost several months to neuroadapt of the multifoci images in the retina. To decide which near add power is right for a given patient, the surgeon must evaluate subjective factors (occupations, hobbies, expectations, concernabout night vision) and objective factors (preoperative visual acuity and refraction error, height/arm length).

Extended depth of focus (EDOF) IOLs are a set of intraocular lenses that extend vision instead of offering discrete close, intermediate, or distance vision. These IOLs based on diffractive, pin-hole or aberration technique, while minimizing the quality of vision compromises and night vision symptoms that are associated with multifocal lenses. The EDOF IOLs are more tolerance higher levels of cylinder error, especially for higher amounts of astigmatism in the range of 0.75D to more than 1.0D. Due to EDOF IOLs delivers less spectacle independence than trifocal IOLs, mini-monovision is common strategy with EDOF IOLs implantation. It set the nondominant eye's target at −0.75D, which relates to an extension of the depth of focus, giving the patient the ability to read at a distance of about 45- to-50 cm, thus optimizing their potential for spectacle independence [50]. EDOF IOLs also can be considered for patients who had history of corneal refractive surgery [34] (**Figure 8**).
