Interpseudophakos Elschnig pearls associated with late hyperopic shift: a complication of piggyback posterior chamber intraocular lens implantation

Cataract Surgery in the Small Adult Eye: A Review

Modern cataract surgery continues to advance, yet intraocular lens (IOL) based surgery in the small adult eye remains challenging. Thorough preoperative assessment and surgical preparation optimise postoperative outcomes in these cases. Advances in IOL power calculation, including artificial intelligence-driven formulas, improve accuracy; however, careful consideration of biometry and IOL power selection is still necessary because inaccuracies can produce significant errors. Limited availability of high-powered IOLs to fully correct high refractive errors may necessitate further intervention. Surgical techniques have evolved to address the unique anatomical challenges of small eyes, improving safety and outcomes. Knowledge of the potential risks inherent in these cases can assist the surgeon in modifying the operative technique accordingly. This review discusses essential preoperative assessments, IOL power selection, surgical techniques, and potential complications, offering guidance for surgeons performing cataract surgery on small adult eyes.

Polypseudophakia: from "Piggyback" to supplementary sulcus-fixated IOLs

Polypseudophakia, the concept of using a second intraocular lens (IOL) to supplement an IOL that has already been placed in the capsular bag, was first used as a corrective measure where the power requirement was higher than that of available single IOLs. Subsequently, the technique was modified to compensate for post-operative residual refractive errors. In these early cases, an IOL designed for the capsular bag would be implanted in the sulcus.  Although these approaches were less than ideal, alternative means of correcting residual refractive errors were not without their limitations: IOL exchange can be traumatic to the eye and is not easily carried out once fibrosis has occurred, while corneal refractive surgical techniques are not suitable for all patients. Piggyback implantation was the term first coined to describe the use of two IOLs, placed together in the capsular bag. The term was later extended to include the procedure where an IOL designed for the capsular bag was placed in the sulcus. Unfortunately, the term piggyback has persisted even though these two approaches have been largely discredited. Intraocular lenses are now available which have been specifically designed for placement in the ciliary sulcus. As these newer IOLs avoid the many unacceptable complications brought about by both types of earlier piggyback implantation, it is time to employ a new terminology, such as supplementary IOL or secondary enhancement to distinguish between the placement of an unsuitable capsular bag IOL in the sulcus and the implantation of an IOL specifically designed for ciliary sulcus implantation. In addition to minimising possible complications, supplementary IOLs designed for the sulcus have expanded the options available to the ophthalmic surgeon. With these new IOLs it is possible to correct presbyopia and residual astigmatism, and to provide temporary correction of refractive errors in growing, or unstable, eyes. This article aims to review the literature available on supplementary IOL implantation in the ciliary sulcus and to summarise the evidence for the efficacy and safety of this intervention. KEY MESSAGES: What is known Polypseudophakia has been used for over 30 years to correct hyperopia or residual refractive error, but early techniques were associated with significant complications. What is new The development of specially designed sulcus-fixated supplementary IOLs significantly reduces the risks associated with these procedures, and has also opened up new opportunities in patient care. The reversibility of the procedure allows patients to experience multifocality, and to provide temporary and adjustable correction in unstable or growing eyes. The terms "secondary enhancement" or "DUET" to describe supplementary IOL implantation are preferential to "piggyback".

Visual and Safety Outcomes of Refractive Correction Procedures Following Lens Removal for Residual Refractive Error: A Systematic Review and Meta-analysis

PURPOSE

To evaluate residual refractive errors after intraocular lens (IOL) extraction and the safety and effectiveness of refractive correction procedures.

METHODS

The eligibility criteria for this systematic review were patients who had undergone cataract or clear lens extraction and had experienced residual refractive error. All study designs were considered for inclusion and non-English publications, non-peer reviewed articles, books, and systematic reviews were excluded. A comprehensive electronic search strategy was employed on PubMed, Scopus, Web of Science, Cochrane, and Embase databases from January 1, 1950, to August 1, 2023.

RESULTS

This review examined 55 articles with 2,223 eyes. Piggyback IOL and IOL exchange are highly effective in correcting both myopia and hyperopia, showing significant improvements in spherical and cylindrical errors. Among corneal-based procedures, laser in situ keratomileusis offers a strong balance, with substantial reductions in both spherical and cylindrical errors, along with a favorable safety profile. Small incision lenticule extraction improves uncorrected distance visual acuity (UDVA), particularly in hyperopic patients, whereas photorefractive keratectomy is effective for both UDVA and astigmatism correction, although it has less impact on corrected distance visual acuity (CDVA). Conductive keratoplasty is effective but has greater variability and a higher incidence of complications.

CONCLUSIONS

Significant improvements in spherical equivalent were consistently observed after treatment across the different procedures. Both UDVA and CDVA demonstrated notable enhancements, suggesting an overall efficacy in improving visual function. Although complications were reported, they were generally low in incidence and varied across procedure types. [J Refract Surg. 2025;41(1):e73-e87.].

Ultrasound biomicroscopy in the management of complex cataract and intraocular lens: A review

Ultrasound biomicroscopy (UBM) is an invaluable investigation for imaging anterior segment structures. Although it is operator-dependent and time consuming, unlike optical-based imaging techniques, it is able to image structures posterior to the iris, such as the zonules, ciliary body and part of the pars plana. It is especially useful in advanced cataracts, traumatic cataracts, subluxed lenses, posterior polar cataracts, and congenital and developmental anomalies affecting the anterior segment. It provides diagnostic information in eyes with complex cataracts or intraocular lens (IOL)-related pathology, and aids in surgical planning in order to minimise complications. In this review, we describe the UBM features of various lenticular pathologies and demonstrate its application in the diagnosis and surgical management of lens and IOL-related pathologies.

Treatment of Nanophthalmos Cataracts: Surgery and Complications

PURPOSE

Cataract surgery in patients with nanophthalmos is complicated for ophthalmologists to perform. Due to the unique ocular anatomy, there is a high incidence of complex complications such as angle-closure glaucoma, fluid misdirection syndrome, and uveal effusion syndrome (UES) in the perioperative period of cataract surgery. This article will discuss the management options for cataract surgery in nanophthalmic eyes and complications.

METHODS

This review is searched through PubMed, focusing on articles published in the past 20 years. Articles were reviewed on the anatomical structure of nanophthalmic cataracts, the pathogenesis of complications, the selection of intraocular lenses, and surgical methods.

CONCLUSION

There is a strong correlation between abnormal ocular anatomy and complications in patients with nanophthalmos. Clinicians must not only select the appropriate intraocular lens formula based on the depth of the anterior chamber but also formulate personalized surgical methods based on its unique anatomical structure to avoid complications.

Successful surgical management of interlenticular membrane by vitreoretinal interlenticular membranectomy (VIM)

The formation of a light scattering interlenticular membrane (ILM) is a known complication of polypseudophakia and has been particularly noted with the use of dual intracapsular Alcon AcrylSof intraocular lenses (IOLs). The treatment options for this condition have largely been restricted to either Nd:YAG laser membranotomy or explantation of the dual IOL complex. In this case report, we describe an unusual case of ILM in a 76-year-old woman whose ILM had formed between her primary intracapsular IOL and her piggyback sulcal IOL. Furthermore, we describe vitreoretinal interlenticular membranectomy (VIM), a novel technique involving a translimbal anterior interlenticular membranectomy using vitreoretinal instrumentation. There were no intraoperative or postoperative complications. Postoperative best-corrected visual acuity was 6/4, maintained for 3 years of follow-up. VIM is offered as a management option for surgeons to address ILM when Nd:YAG laser therapy fails, and the IOLs cannot be safely explanted.

Outcomes of refractive error correction in pseudophakic patients using a sulcus piggyback intraocular lens

PURPOSE

The purpose of this study was to assess the results of a sulcus intraocular lens (Sulcoflex) for pseudophakic refractive errors following phacoemulsification cataract surgery.

METHODS

This retrospective clinical observational cohort study included consecutive eyes in which a Sulcoflex was implanted. Uncorrected distance visual acuity and corrected distance visual acuity as well as refractive outcomes were assessed. The minimum follow-up time required for inclusion was 3 months.

RESULTS

In total, 15 eyes (n = 15) were evaluated. The mean follow-up was 14 months (range: 3-18 months). The Sulcoflex aspheric (653L) was implanted in 13 eyes and the Sulcoflex toric (653T) in two eyes. The preoperative mean logMAR (Snellen) uncorrected distance visual acuity and corrected distance visual acuity were 0.88 (20/150) and 0.27 (20/40), respectively. The postoperative mean logMAR (Snellen) corrected distance visual acuity was 0.15 (20/30). The preoperative mean spherical equivalent was -0.22 ± 5.95 D and the postoperative mean spherical equivalent was -1.59 ± 1.45 D. There was a significant and strong correlation (r = 0.64, p < 0.001) between the attempted and the achieved spherical equivalent.

CONCLUSION

The Sulcoflex is a safe and viable option for patients with residual refractive error following cataract surgery.

New pinhole sulcus implant for the correction of irregular corneal astigmatism

PURPOSE

To evaluate the effect on visual acuity of the implantation of a new intraocular pinhole device (Xtrafocus) in cases of irregular corneal astigmatism with significant visual impairment.

SETTING

University of São Paulo, São Paulo, Brazil.

DESIGN

Prospective case series.

METHODS

Pseudophakic eyes of patients with irregular corneal astigmatism were treated with the pinhole device. The causes of irregular corneal astigmatism were keratoconus, post radial keratotomy (RK), post-penetrating keratoplasty (PKP), and traumatic corneal laceration. The device was implanted in the ciliary sulcus in a piggyback configuration to minimize the effect of corneal aberrations. Preoperative and postoperative visual parameters were compared. The main outcome variables were manifest refraction, uncorrected and corrected distance and near visual acuities, subjective patient satisfaction, and intraoperative and postoperative adverse events and complications.

RESULTS

Twenty-one patients (ages 35 to 85 years) were included. There was statistically significant improvement in uncorrected and corrected (CDVA) distance visual acuities. The median CDVA improved from 20/200 (range 20/800 to 20/60) preoperatively to 20/50 (range 20/200 to 20/20) in the first month postoperatively and remained stable over the following months. Manifest refraction remained unchanged, while a subjective visual performance questionnaire revealed perception of improvement in all the tested working distances. No major complication was observed. One case presented with decentration of the device, which required an additional surgical intervention.

CONCLUSIONS

The intraocular pinhole device performed well in patients with irregular astigmatism caused by keratoconus, RK, PKP, and traumatic corneal laceration. There was marked improvement in visual function, with high patient satisfaction.

Supplementary IOLs: Monofocal and Multifocal, Their Applications and Limitations

Supplemental intraocular lenses (IOLs) have been developed to replace IOLs designed for in-the-bag placement being used as "piggy-back" IOLs in the sulcus due to unacceptable complications. The new IOLs have unique platform designs to avoid these complications. As a result, a new nomenclature is needed to describe the 4 scenarios when supplemental IOL use is now indicated.

Prevention of postoperative capsular bag opacification using intraocular lenses and endocapsular devices maintaining an open or expanded capsular bag

Postoperative capsule opacification is a multifactorial physiological consequence of cataract surgery that remains the most common complication of this procedure. A literature review that included several intraocular lenses (IOLs) and endocapsular devices studied in our laboratory found that devices maintaining the capsular bag in an open or expanded state were associated with improved bag clarity. This observed effect likely occurs secondary to the complex interactions of myriad mechanisms, which include formation of a barrier to lens epithelial cell (LEC) migration, mechanical compression of residual LECs, mechanical stretch at the level of the capsule equator, maintenance of overall bag contour, and enhanced endocapsular circulation of aqueous humor. We review the designs of endocapsular devices and IOLs that minimize the degree of postoperative capsule opacification by preventing capsular bag collapse and discuss the underlying mechanisms that contribute to this phenomenon.

FINANCIAL DISCLOSURE

None of the authors has a financial or proprietary interest in any material or method mentioned.

Refractive outcomes in nanophthalmic eyes after phacoemulsification and implantation of a high-refractive-power foldable intraocular lens

PURPOSE

To evaluate the refractive and postoperative outcomes of a high-power foldable intraocular lens (IOL) in nanophthalmic eyes.

SETTING

Six ophthalmic surgical centers in Canada.

DESIGN

Retrospective case series.

METHODS

Consecutive charts of nanophthalmic patients having cataract extraction and insertion of the CT Xtreme D IOL were reviewed. Demographic and clinical data were collected, including age, sex, axial length (AL), minimum keratometry (K) value and maximum K value, corneal white-to-white (WTW), anterior chamber depth, lens thickness (LT), and complications. The following preoperative and operative data were collected: uncorrected distant visual acuity (UDVA), corrected distant visual acuity (CDVA), sphere, cylinder, and spherical equivalence (SE). The primary outcome measure was change in SE. The secondary outcome measures were changes in UDVA and CDVA.

RESULTS

A total of 21 eyes from 13 patients with a mean follow-up time of 9.6 ± 8.5 months were studied. Mean preoperative data were: age (51.4 ± 15.2 years), AL (16.63 ± 0.68 mm), minimum K value (46.20 ± 2.26 D), maximum K value (47.55 ± 2.34 D), anterior chamber depth (2.60 ± 0.49 mm), WTW (11.08 ± 1.38 mm), LT (4.70 ± 0.97 mm), and IOL power implanted (+49.9 ± 3.3 diopters [D]). SE improved from +16.11 ± 3.26 D preoperatively to +2.00 ± 2.37 D postoperatively (P < .0001). UDVA improved from 1.47 ± 0.30 logMAR preoperatively to 0.74 ± 0.43 logMAR postoperatively (P = .016). CDVA did not change significantly. Five eyes (23.8%) had serious postoperative complications. Of these eyes, 2 had malignant glaucoma, 2 had vitreous hemorrhages, and 1 eye had a vitreous hemorrhage with retinal detachment resulting in visual acuity of no light perception.

CONCLUSION

Implanting foldable high-power IOLs in a series of nanophthalmic eyes yielded significant improvement in UDVA and SE. Cataract surgery in these eyes carries increased risk.

FINANCIAL DISCLOSURE

Iqbal Ike K. Ahmed is a consultant to Carl Zeiss Meditec AG. No other author has a financial or proprietary interest in any material or method mentioned.

Cataract surgery in the small eye

The surgical management of cataract in the small eye presents the ophthalmic surgeon with numerous challenges. An understanding of the anatomic classification in addition to a thorough preoperative assessment will help individualize each case and enable the surgeon to better prepare for the obstacles that might be encountered during surgery. Small eyes are especially challenging in terms of intraocular lens (IOL) calculations and possible current limitations of available IOL powers, which could necessitate alternative means of achieving emmetropia. Surgical strategies for minimizing complications and maximizing good outcomes can be developed from knowledge of the anatomic differences between various small-eye conditions and the pathologies that may be associated with each. A thorough understanding of the challenges inherent in these cases and the management of intraoperative and postoperative complications will ensure that surgeons approaching the correction of these eyes will achieve the best possible surgical results.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Clinical results with a supplementary toric intraocular lens for the correction of astigmatism in pseudophakic patients

PURPOSE

To evaluate the visual outcomes of pseudophakic patients who underwent supplementary toric intraocular lens (IOL) implantation to correct astigmatic refractive errors.

METHODS

Pseudophakic patients referred for the implantation of a supplementary toric IOL (Sulcoflex Toric 653T) were evaluated. Uncorrected and corrected distance visual acuities (UDVA and CDVA, respectively), spherical equivalent (SE) refraction, rotational stability, higher order aberrations (HOA), and photopic glare and no-glare contrast sensitivity (CSV-1000, VectorVision) were evaluated.

RESULTS

A total of 10 eyes of 10 patients were included. The mean age was 56.42 ± 5.9 years (range 45-65 years). Mean follow-up was 6.99 ± 5.1 months (6-18 months). Postoperatively, UDVA improved to 0.10 ± 0.12 (0.3 to -0.1) (p = 0.004) and CDVA to 0.07 ± 0.12 (0.3 to -0.1) (p = 0.021). Mean SE was -0.30 ± 0.56 D (-1.00 to +0.75) (p = 0.001). Mean toric IOL axis rotation at 6-month follow-up was 3.0° ± 2.45° (0-6). Ocular aberrometry values decreased after surgery (for average HOA root mean square, p = 0.008). Photopic contrast sensitivity (for all spatial frequencies) showed a trend for improvement after surgery; however, this was not borne out from the analysis (p&gt;0.05).

CONCLUSIONS

The implantation of the Sulcoflex Toric IOL to correct astigmatism in pseudophakic patients provided excellent visual outcomes, predictability of refractive results, rotational stability, and optical performance. The implantation of this IOL is a safe and effective technique to correct pseudophakic cylindrical refractive errors and reduce spectacle dependence in these patients.

Sulcus anatomy and diameter in pseudophakic eyes and correlation with biometric data: evaluation with a 50 MHz ultrasound biomicroscope

PURPOSE

To evaluate the sulcus anatomy and possible correlations between sulcus diameter and white-to-white (WTW) diameter in pseudophakic eyes, data that may be important in the stability of add-on intraocular lenses (IOLs).

SETTING

University Eye Hospital, Tuebingen, Germany.

DESIGN

Case series.

METHODS

In pseudophakic eyes, the axial length (AL) and horizontal WTW were measured by the IOLMaster device. Cross-sectional images were obtained with a 50 MHz ultrasound biomicroscope on the 4 meridians: vertical, horizontal (180 degrees), temporal oblique, and nasal oblique. Sulcus-to-sulcus (STS), angle-to-angle (ATA), and sclera-to-sclera (ScTSc) diameters were measured. The IOL optic diameter (6.0 mm) served as a control. To test reliability, optic measurements were repeated 5 times in a subset of eyes.

RESULTS

The vertical ATA and STS diameters were statistically significantly larger than the horizontal diameter (P=.0328 and P=.0216, respectively). There was no statistically significant difference in ScTSc diameters. A weak correlation was found between WTW and horizontal ATA (r = 0.5766, P<.0001) and between WTW and horizontal STS (r = 0.5040, P=.0002). No correlation was found between WTW and horizontal ScTSc (r = 0.2217, P=.1217).

CONCLUSIONS

The sulcus anatomy had a vertical oval shape with the vertical meridian being the largest, but it also had variation in the direction of the largest meridian. The WTW measurements showed a weak correlation with STS. In pseudophakic eyes, Soemmerring ring or a bulky haptic may affect the ciliary sulcus anatomy.

Modern cataract surgery: unfinished business and unanswered questions

We summarize information, based on clinicopathologic studies over the past decade, on various cataract intraocular lens (IOL) procedures and modern "specialized" IOLs, that will help surgeons continuously improve long-term results for cataract patients. Although most operations do initially provide excellent refractive correction and visual rehabilitation, late complications occur. These sometimes are missed because they are outside of the routine period of follow-up care. We have tried to determine if the various techniques and IOLs truly deliver the long-term results that we desire. Most safety and efficacy information is derived from the manufacturer and is passed through the U.S. Food and Drug Administration (FDA). This is often based on limited, relatively short-term observations made by the manufacturer. After a lens receives FDA approval, there are few means to assess the outcome of each procedure and lens years later. We rarely hear of a 10- or 20-year follow-up study. We have found that one of the best means to assess long-term results is pathologic analyses. We discuss recently studied aspects of pathologic reactions, such as posterior capsule opacification, intracapsular fibrosis, glistenings, intralenticular opacification, and other issues with the various IOL platforms; we then present a clinicopathological overview of tissues and IOLs from our database. These include hydrophobic and hydrophilic acrylic designs, plate lenses, and a dual optic lens.

Polypseudophakia for cataract surgery: 10-year follow-up on safety and stability of two poly-methyl-methacrylate (PMMA) intraocular lenses within the capsular bag

PURPOSE

To report the long-term follow-up (more than 10 years) of three patients who have undergone polypseudophakia phacoemulsification cataract surgery.

METHODS

A case series of three patients and four procedures. Two poly-methyl-methacrylate (PMMA) intraocular lenses (IOLs) were placed within the capsular bag (P359UV, Storz, Tuttlingen, Germany). No complications occurred peri-operatively. A full ophthalmological examination was performed at 10-year follow-up, looking for decentration, tilt, and complications of interlenticular opacification (ILO) between the IOLs.

RESULTS

Inferior ILO with Elschnig pearls was observed in only one case, and was likely to be visually insignificant. No ILO was observed in the other three eyes. In one patient, the piggyback IOL had been displaced 1-2 mm nasally, but there was no tilt of the IOLs, with the haptics remaining well aligned. There was no displacement or tilt of the piggyback IOL in the other three cases. Corneal endothelial cell count (SP-2000P, Topcon, Tokyo, Japan) was above 1000 cell/mm(2) in all cases.

CONCLUSIONS

With the introduction of foldable IOLs, the piggyback IOL is usually placed in the sulcus, but we have shown good long-term stability and minimal complications of dual PMMA IOLs placed within the bag.

Low-intensity ultraviolet A irradiation of the lens capsule to remove lens epithelial cells during cataract surgery

PURPOSE

To assess the effectiveness and safety of low-intensity ultraviolet A (UVA) irradiation in removing lens epithelial cells (LECs) during cataract surgery and compare them with those of mechanical polishing and no treatment.

SETTING

Eyecove Ophthalmology Clinics, Pune, India.

METHODS

This prospective randomized double-masked study consisted of preoperative screening of 36 patients, of which 30 met the inclusion criteria and were recruited. The patients had routine cataract surgery. A bean-shaped capsulorhexis was performed. After the nucleus and cortex were removed, the capsular bag was irradiated from inside with low-intensity UVA in 1 group. A second group had mechanical polishing, and a third group was not treated. A small flap of the anterior capsule was removed in each patient. The flap was stained and mounted in a Fuchs-Rosenthal chamber. For estimation of effectiveness, the area of capsule covered with epithelial cells was estimated by examination under a light microscope. One day postoperatively, an examination was performed to assess the safety of each technique.

RESULTS

The area of the capsule from which the LECs were removed was significantly larger in the UVA-irradiation group than in the mechanical-polishing group (P = .001) and the no-treatment group (P = .001). There was no significant difference between the mechanical-polishing and no-treatment groups (P>.05). The area of the capsule flap that was covered with LECs was significantly less in the UVA-irradiation group than in the mechanical-polishing group (P = .017) and the no-treatment group (P = .001). The mechanical-polishing group and no-treatment group were not significantly different from each other (P>.05). Corneal edema was significantly less in the UVA-irradiation group than in the mechanical-polishing group (P<.001) and no-treatment group (P = .012). No patient in the UVA-irradiation group had postoperative lid edema; 8 patients in each of the other 2 groups had lid edema. The difference was statistically significant (P<.0001). Pupil size was significantly larger in the UVA-irradiation group than in the mechanical-polishing group and no-treatment group; the difference was significant (both P = .0001). There was no significant difference in pupil size in the mechanical-polishing group and no-treatment group. No significant difference was observed between the 3 groups in visual acuity, conjunctival edema, anterior chamber flare, and intraocular pressure.

CONCLUSION

Ultraviolet A irradiation of the capsular bag was effective and safe in removing LECs from the anterior capsule during cataract surgery.

Primary piggyback implantation using the ReSTOR intraocular lens: Case series

PURPOSE

To assess the postoperative outcomes of piggyback implantation using the AcrySof ReSTOR intraocular lens (IOL) (model SA60D3, Alcon Surgical Laboratories).

SETTING

Hospital Oftalmológico de Brasília, Brasília, Brazil.

METHODS

Thirteen eyes of 7 patients who had phacoemulsification with piggyback IOL implantation were analyzed prospectively. In all cases, a ReSTOR IOL was implanted in the capsular bag and a second silicone IOL was implanted in the ciliary sulcus. Information collected included uncorrected visual acuity (UCVA) at near and distance, best corrected visual acuity (BCVA), and spherical equivalent (SE) before and after surgery.

RESULTS

The patients were followed for 12 months. The mean distance UCVA was 0.25 (20/80) preoperatively and 0.88 (20/23) at the last follow-up (1 year), which was significantly better than before surgery (P<.05). The mean SE was +4.25 diopters (D) +/- 1.5 (SD) preoperatively and +0.15 +/- 0.44 D (range -0.50 to +0.75 D) at 1 year, which was significantly better than preoperatively (P<.05). No patient lost lines of BCVA after surgery. At the last follow-up, all eyes had a near UCVA of J1 and none required spectacles for near or distance vision.

CONCLUSION

Piggyback implantation using the ReSTOR IOL appeared to be a safe and efficient procedure providing high-quality visual acuity for near and distance vision in selected patients.

Primary piggyback implantation of 3 intraocular lenses in nanophthalmos

We present a patient with bilateral nanophthalmos who had uneventful cataract extraction in the right eye with primary implantation of 3 intraocular lenses (IOLs) of 2 different materials: a 30 diopter (D) acrylic IOL and a 9 D silicone IOL in the capsular bag and a 30 D silicone IOL in the ciliary sulcus. Subsequently, cataract extraction was done in the left eye with bag-sulcus implantation of two 30 D silicone IOLs. The use of 3 IOLs in 1 eye was necessary because the highest available power of acrylic and silicone IOLs at our institution was 30 D. The only short-term complications were temporary corneal edema and partial displacement of the sulcus IOL anterior to the iris in the right eye and bilateral posterior capsule opacification. The late complication of interlenticular opacification was not present 1 year after piggyback IOL implantation.

Scheimpflug measurement of intraocular lens position after piggyback implantation of foldable intraocular lenses in eyes with high hyperopia

PURPOSE

To investigate the position of 3-piece foldable intraocular lenses (IOLs) after piggyback implantation for high hyperopia.

SETTING

University Eye Hospital, Johann Wolfgang Goethe University, Frankfurt am Main, Germany.

METHODS

Eight eyes of 5 highly hyperopic patients had phacoemulsification and implantation of 2 foldable IOLs. In 3 eyes, both IOLs were implanted in the capsular bag. In 5 eyes, 1 IOL was placed in the capsular bag and the second IOL in the ciliary sulcus. Intraocular lens optic tilt and decentration, combined thickness of both IOLs, and anterior chamber depth (ACD) were measured postoperatively over a period of 18 months using Scheimpflug photography.

RESULTS

All eyes with both IOLs in the capsular bag showed interpseudophakic opacification, with a mean increase in combined IOL thickness of 0.4 mm, a decrease in ACD of 0.3 mm, and a corresponding hyperopic shift of 4.00 diopters. Eyes in which the anterior IOL was placed in the ciliary sulcus showed no changes in refraction or combined IOL thickness. In these eyes, the anterior IOL had a higher mean decentration (0.49 mm +/- 0.20 [SD] after 12 months) than the posterior IOL (0.21 +/- 0.13 mm after 12 months).

CONCLUSIONS

Piggyback IOL implantation with placement of 2 foldable IOLs in the capsular bag can be followed by a hyperopic shift that may be caused in part by displacement of the IOLs. Placement of the anterior IOL in the ciliary sulcus can lead to higher decentration of this IOL.

Secondary diffractive bifocal piggyback intraocular lens implantation

PURPOSE

To assess the efficacy and safety of implanting a bifocal diffractive intraocular lens (IOL) using the piggyback technique to provide pseudoaccommodation.

SETTING

Instituto Oftalmológico Fernández-Vega, Oviedo, Spain.

METHODS

This prospective noncomparative case series included 6 pseudophakic emmetropic patients who had a monofocal IOL implanted in the capsular bag. All eyes had secondary piggyback Acri. Twin bifocal diffractive IOL (Acri.Tec) implantation in the ciliary sulcus to provide pseudoaccommodation. Contralateral implantation of 1 Acri. Twin near-weighted 733D IOL in the nondominant eye and 1 Acri. Twin distance-weighted 737D IOL in the dominant eye was performed. Monocular and binocular best distance-corrected visual acuity and distance-corrected near visual acuity were evaluated 6 months after surgery.

RESULTS

The mean binocular best distance-corrected visual acuity and distance-corrected near visual acuity were -0.080 +/- 0.056 logMAR and -0.016 +/- 0.037 logMAR, respectively. There were no statistically significant differences in binocular best distance-corrected acuity after the piggyback IOL implantation (P>.01). The differences between monocular and binocular visual acuity were the result of the distance- and near-weighted light distribution of the Acri. Twin IOLs. All IOLs were well centered with no tilt. Two eyes had pupillary capture of the optic.

CONCLUSIONS

The Acri. Twin bifocal diffractive IOL implanted in the ciliary sulcus using the piggyback technique provided pseudoaccommodation in emmetropic pseudophakic eyes. Binocular implantation of these IOLs should be performed considering the differences in light distribution of the distance-weighted IOL and the near-weighted IOL models.

Cataract surgery in the small adult eye

Microphthalmos is a rare condition that is often associated with several other ocular abnormalities. Given the considerable differences between microphthalmic and anatomically normal eyes, cataract surgery is technically demanding in these patients, and special attention must be given to adequate preoperative planning of these procedures. Furthermore, the unique nature of these surgeries creates a particular subset of intraoperative and postoperative complications. However, with the advent of piggyback intraocular lens placement, the visual outcomes of cataract surgery in small adult eyes have improved considerably over the past 20 years. This review discusses the nature of the microphthalmic eye, and addresses proper pre-, intra-, and postoperative care of the microphthalmic patient.

Interlenticular opacification: Dual-optic versus piggyback intraocular lenses

PURPOSE

To evaluate and compare the incidence of capsular bag opacification, particularly interlenticular opacification (ILO), in rabbit eyes implanted with a dual-optic silicone intraocular lens (IOL) or piggyback lenses.

SETTING

John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

METHODS

Ten dual-optic study IOLs (Synchrony), 10 control pairs of piggyback silicone-plate lenses, and 10 control pairs of piggyback single-piece hydrophobic acrylic lenses were implanted in the capsular bag of 30 rabbit eyes following phacoemulsification. After a 6-week follow-up, the rabbits were killed and their eyes enucleated. Anterior capsule opacification and posterior capsule opacification were graded on a 0 to 4 scale from a posterior or Miyake-Apple view. Interlenticular opacification was noted in relation to the center of the interlenticular space (periphery, paracentral, and central area) and to the number of quadrants involved. The eyes were then evaluated histopathologically.

RESULTS

Postoperative inflammatory reaction was similar in all groups. Interlenticular opacification formation was statistically different among the 3 groups of lenses (ILO extension, P = .0013, and ILO extension x ILO quadrants, P = .0023; Kruskal-Wallis test). Pairwise post comparisons of ILO formation showed that the differences between the study IOL group and the silicone-plate lens group were not significant. Interlenticular opacification post comparisons between the hydrophobic acrylic lenses and the study lens or the silicone-plate lenses were significant (P = .002 and P = .001, respectively). Histopathologic examination showed extension of the proliferating cortical material from the peripheral Soemmering's ring into the interlenticular space, causing ILO, especially with the pairs of hydrophobic acrylic lenses.

CONCLUSIONS

In this rabbit model, ILO was significantly associated with pairs of hydrophobic acrylic lenses implanted in the bag. This study appears to confirm clinical observations that implantation of 2 silicone-plate lenses in the bag is not associated with ILO. There was also a relative lack of ILO with the dual-optic silicone lens.

Elevated intraocular pressure in secondary piggyback intraocular lens implantation

We report 2 cases of postoperative intraocular pressure (IOP) elevation in secondary piggyback intraocular lens (IOL) implantation without history of glaucoma or ocular hypertension. A 74-year-old woman with myopic pseudophakia and a 68-year-old man with hyperopic pseudophakia received secondary piggyback AcrySof IOL implantation in their left eyes. In both patients, the left IOP gradually increased and sustained around 30 mm Hg for about 1 year. In the first, IOP continued elevating despite topical and systemic medications. There was an episode of pupillary block in the second. Gonioscopically, heavier trabecular meshwork pigmentation in their left eyes was observed. Because of this, the 2 IOLs implanted were removed and replaced by an adequate IOL and trabeculotomy was performed in the former. The AcrySof IOL has a truncated optic edge, which increases the risk for chafing the iris, resulting in pigment dispersion syndrome; thus, it would be a poor choice for a sulcus-placed piggyback implantation.

Piggyback intraocular lens implantation to correct myopic pseudophakic refractive error after penetrating keratoplasty

PURPOSE

To determine the safety and efficacy of implanting a second intraocular lens (IOL) to correct myopic pseudophakic refractive error after penetrating keratoplasty (PKP).

SETTING

Department of Ophthalmology, Toronto Western Hospital, Toronto, Ontario, Canada.

METHODS

In this retrospective case series, 6 eyes of 6 post-PKP pseudophakic patients had a second piggyback IOL implantation to correct a residual myopic refractive error. The uncorrected visual acuity (UCVA) and the best corrected visual acuity (BCVA) were measured at regular intervals during a 7-month follow-up. Efficacy was determined by the achieved refractive correction and Snellen UCVA measurements. Safety was measured by loss of BCVA and complications (intraoperative and postoperative).

RESULTS

The UCVA improved in all cases. Five patients achieved a BCVA of 20/40 or better postoperatively. Before surgery, the mean spherical equivalent (SE) was -8.08 diopters (D) (range -6.13 to -12.00 D). After surgery, the mean SE was -0.94 D (range -2.38 to +0.25 D). Four patients were within +/-1.50 D of emmetropia. There were no intraoperative or postoperative complications.

CONCLUSION

Implanting a piggyback IOL was a safe and effective means of correcting myopic pseudophakic refractive error post PKP.

Refractive lensectomy and accommodating lens implantation in a case of hyperopia

We present a 39-year-old woman with high hyperopia who developed an intolerance to contact lenses due to dry-eye syndrome and Grave's disease. Refractive lensectomy with implantation of a custom-made +31.00 diopter (D) accommodating intraocular lens (IOL) (1CU, HumanOptics) was performed in both eyes. This foldable IOL has modified haptics with transmission elements that allow axial movement of the IOL optic and capsular bag secondary to contraction of the ciliary muscle. The calculated pseudophakic accommodation induced by the anterior shift of a +31.00 D IOL is 2.20 D per millimeter of axial displacement. After 6 months, the accommodative range determined by defocusing was 3.00 D. The subjective near point with best distance correction was 32.00 cm. Refractive lensectomy and implantation of an accommodating IOL based on focus shift may be a refractive solution in eyes with high hyperopia and a short axial length.

Clear lens extraction with intraocular lens implantation for hyperopia

PURPOSE

To analyze the results of clear lens extraction (CLE) with posterior chamber intraocular lens (IOL) implantation to correct hyperopia.

SETTING

Eye Research Center and Dr. Agarwal's Eye Hospital, Chennai, India.

METHODS

This prospective study comprised 20 hyperopic eyes of 12 patients between 19 and 50 years who had CLE with posterior chamber IOL implantation. Five patients had peripheral iridectomy during CLE as the angles were occludable.

RESULTS

The mean hyperopic spherical equivalent refraction was +6.66 diopters (D) +/- 2.17 (SD) (range +4.75 to +13.00 D). The IOL power was calculated using the Holladay 2 formula. The mean follow-up was 16.96 months (range 6 to 35 months). The mean postoperative uncorrected visual acuity was 0.45 +/- 0.25 (range 0.10 to 1.00), a mean improvement of 3 Snellen lines from preoperatively. The mean postoperative best corrected visual acuity (BCVA) was 0.63 +/- 0.30, a mean improvement of 1 Snellen line. Three patients gained 2 lines of BCVA and 2 patients, 1 line. One patient lost 1 line of BCVA. Seventy percent of patients were within +/-0.50 D of the intended refraction.

CONCLUSION

The results indicate that CLE with posterior chamber IOL implantation is safe, predictable, and effective.

Interlenticular opacification of piggyback acrylic intraocular lenses

A dense interlenticular opacification developed 18 months after cataract surgery in a hyperopic patient with 2 acrylic piggyback intraocular lenses (IOLs) placed in the capsular bag. The patient developed a hyperopic shift with decreased vision, requiring explantation of the lenses. The dense interlenticular opacification did not allow separation of the lenses intraoperatively because of the tight adherence of the 2 IOLs.

Correcting high astigmatism with piggyback toric intraocular lens implantation

An 86-year-old man presented for cataract surgery with corneal astigmatism of 5.12 diopters (D). After cataract extraction with small-incision techniques, 2 toric plate-haptic silicone intraocular lenses (IOLs) were implanted in the capsular bag, each with a 3.50 D cylinder add (2.30 D at the spectacle plane). Six weeks postoperatively, corneal astigmatism was 3.38 D at 70 degrees and refractive astigmatism was 1.00 D at 20 degrees. Uncorrected visual acuity was 20/40. No IOL rotation was observed. Implantation of piggybacked toric lenses may be a viable option for correcting moderate to high astigmatism.

Analysis of elements of interlenticular opacification

PURPOSE

To report the histopathologic and ultrastructural features of three cases of interlenticular opacification (ILO) between piggyback intraocular lenses.

DESIGN

Interventional case series with clinicopathologic correlation.

METHODS

Three pairs of acrylic piggyback lenses were explanted due to decrease in visual acuity associated with ILO. Lenses were evaluated with gross and light microscopic examinations in all cases. The anterior lens in one case was examined with scanning electron microscopy and energy dispersive x-ray spectroscopy.

RESULTS

The material opacifying the interlenticular space was composed mostly of retained/regenerative cortical material in all cases. From the peripheral interface towards the central interface, the opacifying material changed as the interlenticular space was progressively narrower. The material attached to the peripheral interface, where the interlenticular space was wider, was very thick. At the midperipheral interface, the thick cortical material was broken into multiple globules due to liquefactive degeneration. At the paracentral zone, compression of the globules formed a flat, compact layer of an amorphous material. At the central interface (contact zone), almost no material could be found between the piggyback lenses.

CONCLUSIONS

Analyses of ILO cases where all the components of the opacifying material were in situ allowed us to confirm that the pathogenesis of this complication is similar to that of posterior capsule opacification; thus, careful removal of lens epithelial cells and cortical material is mandatory in piggyback implantation.

Correction of pseudophakic anisometropia with the Staar Collamer implantable contact lens

PURPOSE

To assess the role of the Staar Surgical implantable contact lens (ICL) for the correction of pseudophakic anisometropia.

SETTING

Oxford Eye Hospital, Oxford, and Rosen Eye Center, Alexandra Hospital, Manchester, United Kingdom.

METHODS

Six patients with pseudophakic anisometropia ranging from 2.0 to 7.9 diopters (D) (mean 4.4 D) had ICL implantation as an alternative to intraocular lens (IOL) exchange or conventional piggyback IOLs.

RESULTS

All patients had a reduction in anisometropia to asymptomatic levels. The mean reduction was 3.15 D. No patient experienced adverse effects.

CONCLUSIONS

The implantable contact lens offers an alternative approach to the management of pseudophakic anisometropia that avoids some of the risks associated with IOL exchange, corneal refractive surgery, and conventional piggyback IOLs.

Primary polypseudophakia for cataract surgery in hypermetropic eyes: refractive results and long term stability of the implants within the capsular bag

AIM

To determine the long term visual and refractive results, and stability and complications of primary polypseudophakia using poly(methylmethacrylate) (PMMA) intraocular lenses (IOLs) for cataract surgery in hypermetropic eyes.

METHODS

Prospective study of 15 short or hypermetropic eyes undergoing phacoemulsification with primary polypseudophakia with two PMMA IOLs implanted within the capsular bag.

RESULTS

The spherical equivalent was reduced from a mean +4.87 (SD 3.00) dioptres (D) to -0.12 (1.40 D), and the deviation from the intended refraction was +0.005 (1.30) D, 23.6 (12.36) months post-implantation. The deviation from intended refraction was not statistically significant (p = 0.989; paired t test). Postoperative best corrected visual acuity (BCVA) was 6/12 or better in all eyes without macular or optic nerve co-morbidity. Interlenticular opacification (ILO) in the form of peripheral Elschnig pearls was seen in four (26.67%) eyes. A new type of ILO in the form of usually pigmented deposits in the central interface developed in five (33.33%) eyes and resulted in the appearance of Newton's rings in three. None of the eyes with ILO had any loss of BCVA or hyperopic shift. Six (40%) eyes were within 1 D from the intended refraction and 14 (93.33%) within 2 D. There was no statistically significant difference in the accuracy of the two intraocular lens calculation formulas used (SRK II and SRK/T).

CONCLUSION

Peripheral Elschnig pearl-type ILO can occur as a late complication of primary in the bag implantation of two PMMA IOLs. A new type of ILO is described. Both types of ILO have not to date resulted in deterioration of visual acuity in our cohort. Use of appropriate biometry techniques and IOL calculation formulas may yield more accurate refractive results.

Piggyback implantation using the AMO array multifocal intraocular lens

Piggyback intraocular lens (IOL) implantation allows refractive correction in cases in which the IOL power requirement exceeds that of the available lenses. By combining a piggyback technique with the use of a multifocal IOL, one can obtain the optical advantages of both, achieving high-quality visual acuity for distance and near vision and reducing the optical aberrations of extremely high-powered single IOLs. We report 5 hyperopic patients (6 eyes) who had phacoemulsification and in-the-bag implantation of 2 foldable IOLs in the bag, a silicone multifocal IOL placed in front of a silicone monofocal IOL. Good results were obtained in near and distance uncorrected visual acuities, and patient satisfaction was excellent in all cases. However, in 2 cases, the anteriorly placed IOL was exchanged because of incorrect power calculation. Piggyback IOL implantation with a multifocal lens appears to be a safe, efficient procedure and a good refractive solution.

Neodymium:YAG treatment of interlenticular opacification in a secondary piggyback case

Interlenticular opacification (ILO) developed 7 months after secondary acrylic piggyback lens implantation in which the anterior lens was placed in the bag. This resulted in glare and a hyperopic shift. Treating the ILO with the neodymium:YAG laser successfully reduced the glare and corrected the hyperopic shift.