Management of sequential intraocular lens dislocations in a single eye following prior complicated cataract surgery: A case report

Abstract

Dislocation of the intraocular lens after cataract surgery is uncommon but can cause a serious complication. We present a rare case of a patient with a dislocated posterior chamber intraocular lens and subluxated anterior chamber intraocular lens in the same eye, including its management, complications, and visual outcomes. A 65-year-old man with a history of cataract surgeries was found to have two displaced intraocular lenses in one eye, one subluxated within the anterior chamber and another dislocated into the vitreous cavity. Surgical procedures were performed to remove both displaced intraocular lenses, followed by the management of postoperative complications. After removal of intraocular lens implants via pars plana vitrectomy and insertion of scleral-fixated intraocular lens, the patient developed postoperative cystoid macular edema and epiretinal membrane. Subtenon triamcinolone acetonide injection partially resolved the cystoid macular edema, and the visual outcome was satisfactory. Understanding this case may aid in surgical planning and facilitate effective postoperative management of complications, ultimately leading to an optimal visual outcome.

Introduction

Cataract surgery is a common operative approach to remove a cloudy crystalline lens, followed by intraocular lens (IOL) implantation to restore focused vision. Encountering IOL dislocation after cataract surgery is uncommon but potentially serious. A dislocated IOL may compromise vision and increase the risk of permanent vision loss due to trauma to posterior ocular structures, such as retinal detachment, uveal inflammation, choroidal bleeding, secondary glaucoma, and macular edema.^1,2 Postoperative dislocations of IOLs can be classified as either early or late. Early dislocation of the IOL usually occurs due to inadequate fixation of the IOL in the capsular bag or a zonular defect, often associated with connective tissue disorders, high myopia, or retinitis pigmentosa. Late dislocation typically develops years after surgery, resulting from zonular weakness and capsular contraction secondary to aging, trauma, or other factors.^3,4 Immediate surgical intervention is often necessary to reposition the IOL or exchange the IOL to prevent vision-threatening complications. However, this case describes a patient who presented with an untreated dislocated IOL. This case report was prepared in accordance with the Case Report (CARE) guidelines, and the completed CARE checklist is provided in Supplemental Material.

Case report

A 65-year-old male underwent left eye cataract surgery in 2019. Following the operation, he was informed that the posterior chamber intraocular lens (PCIOL) implanted was unstable. Subsequently, IOL repositioning was attempted but was unsuccessful, as the PCIOL dislocated into the vitreous cavity intraoperatively. An anterior chamber intraocular lens (ACIOL) was simultaneously implanted during the same surgery. Following the dislocation of the PCIOL, the previous surgeon advised that its removal was unnecessary and proceeded with the implantation of an ACIOL. Subsequently, he developed secondary glaucoma in that eye and was treated with guttae timolol maleate twice a day.

The patient presented to our eye center 2 years later with visual disturbance in the left eye. On examination, visual acuity was 20/40 in the right eye and ~20/1200 in the left, corresponding to counting fingers. Intraocular pressure was 16 mmHg in both eyes. A huge patent surgical peripheral iridotomy was noted at 10–11 o’clock. The presence of peripheral iridectomy scars suggests that the patient had likely undergone a previous anti-glaucoma surgical procedure. The anterior chamber was deep, with the presence of an ACIOL. However, one of its haptics was incarcerated within the peripheral iridotomy (Figure 1). It is also plausible that incarceration of the ACIOL haptic within the iridectomy site contributed to its subluxation. A free-floating PCIOL was found in the vitreous cavity (Figure 2). Macular optical coherence tomography (OCT) was not performed at presentation because the dislocated PCIOL limited macular visualization. Clinical fundus examination by a retinal surgeon noted a flat retina with no obvious cystoid macular edema (CME), although subtle changes could not be excluded.

Figure 1.

Anterior segment photograph showing an ACIOL with one haptic captured at a large surgical peripheral iridotomy at 11 o’clock.

Figure 2.

Fundus image showing a dislocated PCIOL lying in the inferior vitreous cavity.

Operative procedures were performed to manage these unusual complications. A corneal incision was made to remove the subluxated ACIOL, followed by closure with 10-0 nylon sutures. A pars plana vitrectomy (PPV) was then performed immediately by the vitreoretinal surgeon, who grasped the dislocated PCIOL with an end-grasping forceps and brought it to the anterior chamber. The limbal incision sutures were removed, and the PCIOL was extracted through the same limbal incision. A single-piece PMMA scleral-fixated intraocular lens (SFIOL; CZ70BD) was then implanted using the ab externo scleral fixation technique. Two scleral flaps were created 180° apart, and a straightened suture was passed beneath each flap about 2 mm posterior to the limbus, then externalized through the limbal incision. The suture ends were tied to the IOL haptics, the lens was inserted, and the sutures were secured beneath the scleral flaps to ensure stability. ⁵ No intraoperative difficulties were encountered. Postoperative medications included topical levofloxacin 0.5%, prednisolone acetate 1%, and nepafenac every 2 h, as well as lubricating eye gel at night. In addition, oral prednisolone 5 mg tablets and paracetamol 500 mg tablets were administered.

On postoperative day 1, visual acuity was 20/120, and intraocular pressure was 13 mmHg. The IOL was well-positioned, and the retina remained flat. On day 10, his vision improved to 20/60 + 2 (20/30 − 1 with pinhole). Topical eye drops were subsequently reduced to every 4 h due to reduced inflammation. At the seventh postoperative week, the patient complained of eye discomfort, and intraocular pressure was elevated to 38 mmHg. Timolol maleate 0.5% eye drop was prescribed twice daily to reduce the patient’s intraocular pressure, and all sutures were removed on the same day. At the ninth-week follow-up, intraocular pressure had normalized to 16 mmHg, and the patient was advised to continue taking timolol maleate 0.5% twice daily (Figure 3).

Figure 3.

Anterior segment photo at ninth-week post PPV showing a clear cornea.

At the 18-week follow-up, his vision decreased to 20/80 (20/40 with pinhole). OCT revealed CME and mild epiretinal membrane (ERM; Figure 4(a) and (b)). Subtenon triamcinolone acetonide injection was administered to treat CME. Repeated OCT 2 months later showed partial resolution of CME (Figure 4(c) and (d)). At the 1-year follow-up, clinical refraction was +0.50/−0.75 × 79 in the right eye and −0.50/−2.00 × 90 in the left eye, with best-corrected visual acuity of 20/25 and 20/30 − 2, respectively. The patient reported satisfaction with his vision, enabling him to conduct activities of daily living. Figure 5 provides a summary of the event within the context of a clinical timeline. At the 2-year follow-up, the IOL remained well-centered and stable, with slow progression of the ERM, which continues to be monitored.

Figure 4.

Optical coherence tomography showing CME and mild ERM: (a, b) before subtenon triamcinolone acetonide injection and (c, d) 2 months after subtenon triamcinolone acetonide injection, demonstrating partial resolution of CME.

Figure 5.

Clinical timeline summarizing the key events associated with the patient’s presentation, management, and outcome.

Discussion

Various approaches have been described for managing IOL dislocation, including repositioning and IOL exchange. In cases of decentered IOLs with intact zonules and capsular bags, repositioning of the IOL using iris suture, scleral fixation, or sulcus placement was recommended to stabilize the lens sitting while preserving the capsular bag.^6,7 IOL exchange is recommended in cases of zonular weakness, involving removal of the dislocated IOL and implantation of alternative designs such as ACIOLs, SFIOLs, or iris-fixated IOLs.^8,9 For partial IOL dislocations, removal of the lens may be performed by intraocular folding, lens cutting, or lens dissection in one piece.^6,7 When the IOL is dislocated into the vitreous cavity, PPV remains a safe and effective method.^8,9

In the present case, the PCIOL was left in situ after dislocation into the vitreous cavity, and the previous surgeon subsequently implanted an ACIOL. The rationale for this management was undocumented and deviates from standard surgical practice, as the retained dislocated PCIOL can induce intraocular inflammation, vitreoretinal traction, or secondary glaucoma. While the intentional implantation of two IOLs, the piggyback IOLs technique, has been used for specific refractive correction, these were controlled, purpose-driven procedures involving one IOL in the capsular bag and another in the sulcus.^10,11 In our case, the placement of an ACIOL while a dislocated PCIOL remained in the vitreous was unlikely intentional and resulted in mechanical and inflammatory complications.

Although IOL dislocation has been widely reported, the coexistence of two IOLs in the same eye is rare. Emanuelli and William described three cases in which a secondary IOL was implanted while a dislocated PCIOL remained within the posterior segment. ¹² In all cases, PPV was performed to remove the dislocated IOL while preserving or repositioning the secondary IOL to restore optical alignment. ¹² Their findings emphasized the importance of removing unstable IOLs to prevent CME, mechanical irritation, and fluctuating visual function.

Similarly, Andreanos et al. reported an 84-year-old woman with intermittent visual loss due to the concurrent ACIOL and prolapsed PCIOL in the anterior chamber. ¹³ Although surgical intervention was declined, the authors recommended removal of the ACIOL with scleral fixation of the PCIOL as the optimal management strategy. ¹³ Chakraborty and Choudhury described another case with both ACIOL and partially subluxated PCIOL in the anterior chamber. ¹⁴ Surgical removal of both IOLs was performed, followed by implantation of a sulcus-fixated IOL, as adequate capsular support was present. ¹⁴

Jain and Gilhotra reported two cases of coexisting IOLs following complicated cataract surgery, where the PCIOL dislocated intraoperatively and an ACIOL was immediately implanted to restore optical function. ¹⁵ Both patients underwent PPV within days of surgery to remove the dislocated PCIOL through a limbal incision made away from the ACIOL haptics, thereby minimizing endothelial trauma. ¹⁵ Their approach demonstrated that prompt removal of the posteriorly dislocated IOL reduces the risk of vitreoretinal traction, secondary glaucoma, and inflammatory sequelae. In contrast, Turgut et al. described an asymptomatic case of double IOLs, a sulcus-fixated PCIOL, and a foldable IOL resting on the inferior retina, where long-term follow-up observation was chosen due to stable vision and absence of intraocular inflammation. ¹⁶

Mei et al. reported a complex case involving an ACIOL and two dislocated PCIOLs within the vitreous cavity, accompanied by vitreous prolapse, CME, and localized retinal detachment. ¹⁷ Both intravitreal IOLs were surgically removed during PPV, and the retinal detachment was successfully repaired, although postoperative ACIOL subluxation and corneal edema limited recovery. ¹⁷ Similar to Mei et al., our case demonstrated that the unrecognized or retained IOLs in the vitreous can lead to secondary complications, including glaucoma, CME, and ERM, highlighting the need for complete IOL removal and secure secondary fixation with an SFIOL.

Unlike the cases described by Jain and Gilhotra, where early intervention was performed, the dislocated PCIOL in our case remained in the vitreous cavity for 2 years. This delay contributed to the development of secondary glaucoma, ACIOL instability, CME, and ERM. Consequently, PPV with removal of both IOLs and secondary SFIOL implantation was performed. Despite the delayed intervention and surgical complexity, the patient achieved a favorable visual outcome, with best-corrected visual acuity of 20/30. These findings align with previous reports, highlighting that definitive removal of unstable IOLs and appropriate secondary fixation are essential for achieving long-term visual stability.

An SFIOL was selected as the preferred method for restoring visual function and ensuring long-term stability. Reimplantation of an ACIOL was avoided because the patient’s previous ACIOL had caused haptic capture at the surgical iridotomy site, leading to visual disturbance. Sulcus-fixated IOLs were also unsuitable, as the dislocated PCIOL indicated inadequate capsular and zonule support. ¹⁸ An iris-fixated IOL was not favored due to its higher risk of endothelial cell loss, chronic inflammation, and potential for iris atrophy, particularly in eyes with prior anterior segment surgery. ¹⁹ Scleral fixation provides a more secure posterior placement while minimizing the risk of recurrent IOL instability and anterior segment complications. ²⁰

Comprehensive management required the removal of both IOLs and the placement of an SFIOL. The patient later developed postoperative CME, which is a known complication after PPV and IOL exchange. Reported CME incidence varies substantially with case complexity. In uncomplicated procedures, such as routine IOL exchange or uneventful cataract surgery, CME has been reported in ~7.6%–9.6% of eyes.^8,21 and is typically transient. In contrast, complicated cases, including vitrectomy for retinal detachment or eyes with significant intraoperative trauma, show higher rates of up to 17.1%. ²² These complications are thought to result from subclinical posterior segment inflammation, prolonged surgical duration, and mechanical trauma.^10–13 This patient had been treated with Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) and steroid eye drops to suppress inflammatory responses and reduce scar formation after the surgery. ¹⁵ This indicated that subtenon triamcinolone acetonide injection was a better treatment option to overcome CME for this case due to steroid-induced intraocular pressure elevation. ¹⁶ This decision was supported by prior studies demonstrating that subtenon injections are associated with less significant IOP elevation compared to intravitreal triamcinolone and carry a lower risk of ERM progression.^17,18 In addition, the postoperative CME in this case showed improvement following subtenon triamcinolone acetonide injection, consistent with previously reported findings in similar cases of postoperative CME secondary to PPV. ²³

Although surgical-induced astigmatism (−2.00 diopters) was noted due to the large limbal incision and suturing, best-corrected vision was preserved with glasses. The patient’s visual outcome was comparable or superior to those reported in previous studies of vitrectomy for IOL dislocation.^24–26 According to Lashgari et al., the majority of patients underwent PPV for a dropped nucleus and achieved visual acuity of 20/40 or better, while poor visual outcomes (worse than 20/40) were mainly associated with prior complicated cataract surgery. ²⁴ This finding is similar to that of Son et al., who reported that more than half of the patients experienced significant vision improvement to 20/40 or better with the best correction after PPV for IOL exchange. ²⁵ Furthermore, the final visual outcome of the current case report exceeded the average postoperative visual acuity of 20/63 reported in a previous study of PPV for posterior dislocated IOL. ²⁶ Postoperative collaboration with an optometrist was essential in optimizing refractive correction and ensuring the best functional vision, highlighting the importance of multidisciplinary care in maximizing postoperative visual outcomes. ²⁷

This case illustrates both its strengths and limitations. The report describes the rare coexistence of ACIOL and PCIOL within a single eye, demonstrating the importance of careful clinical assessment and strategic surgical planning that led to a successful visual recovery. Limitations include the absence of preoperative macular OCT, which restricted baseline evaluation, and the single-case design, limiting generalizability. Despite these, the report provides practical insight for managing complex IOL-related complications.

Conclusion

This case highlighted the surgical approach for a rare presentation involving both subluxated ACIOL and a dislocated PCIOL in one eye. The patient was successfully managed with PPV, removal of both IOLs, and implantation of an SFIOL. Although postoperative complications of CME and ERM developed, appropriate management led to satisfactory visual outcomes. In addition, thorough assessment and collaboration among ophthalmologists and optometrists are key to achieving favorable anatomical and visual outcomes. However, early recognition and urgent referral for IOL exchange are crucial to prevent serious complications and irreversible vision loss.

Supplemental Material

sj-pdf-1-sco-10.1177_2050313X251408229 – Supplemental material for Management of sequential intraocular lens dislocations in a single eye following prior complicated cataract surgery: A case report

Supplemental material, sj-pdf-1-sco-10.1177_2050313X251408229 for Management of sequential intraocular lens dislocations in a single eye following prior complicated cataract surgery: A case report by Jacqueline Ying Liew, Pui Theng Yong, Angela Voon Pei Loo, Jiunn Loong Ling, Visvaraja Subrayan and Jessie Wei Liew in SAGE Open Medical Case Reports