Purpose
To review the clinical features, treatments, and outcomes of patients with retained lens fragments in the anterior chamber after phacoemulsification with an intact posterior capsule.
Design
Retrospective, interventional case series.
Methods
setting : Duke University Eye Center. study population : Fifty-four eyes of 54 patients with a diagnosis of retained lens fragment in the anterior chamber following otherwise uncomplicated phacoemulsification cataract surgery. Patient demographics, clinical examination findings, ocular biometry measurements, treatment received, and pre– and post–lens fragment removal visual acuity were recorded. main outcome measures : Corneal edema, time to surgical extraction of lens fragment, and visual acuity.
Results
All lens fragments were located in the inferior angle or the inferior anterior chamber, with 13% of cases requiring gonioscopy for diagnosis. Fifty-six percent of eyes had associated corneal edema, most often located inferiorly. Forty-four percent of patients were initially managed medically, but in all 54 cases the lens fragment was eventually removed surgically. The mean time to removal of the lens fragment from the date of cataract surgery was 70 days (range 1 day – 30 months). Five patients had corneal edema that did not resolve following fragment extraction and 3 eventually received an endothelial keratoplasty. Best-corrected visual acuity improved from an average of 20/51 before lens fragment removal to 20/28 after surgical extraction ( P < .00001).
Conclusions
Corneal edema is common in the setting of retained lens fragments and can evolve to corneal decompensation requiring transplantation. Inferior corneal edema, in particular, should alert the practitioner to possible retained lens fragment. Surgical removal of retained lens fragments should be considered at the time of diagnosis.
Retention of lens fragments within the anterior chamber following uncomplicated phacoemulsification cataract surgery is a relatively rare occurrence. An exact incidence of this phenomenon is difficult to estimate. Based on a study by Dada and associates, retained nuclear fragments occur in less than 1% of routine cataract cases. This series of 1000 consecutive cases showed that nuclear lens fragments were not identified postoperatively despite their frequent presence intraoperatively after phacoemulsification. Despite its rarity, based on the authors’ experience and informal polls conducted by an author (T.K.) at large meetings, nearly every cataract surgeon has experienced a case of a retained lens fragment after cataract surgery. Moreover, there is reason to believe that with new lens fragmentation patterns available on many femtosecond laser platforms, the incidence of retained lens pieces may significantly increase.
When it does occur, retention of lens fragments is known to increase the risk of persistent postoperative anterior chamber inflammation and corneal edema. The pathophysiologic mechanism of endothelial dysfunction in this clinical setting is not entirely understood, but leading theories include mechanical trauma vs immune-mediated processes. Several case studies have demonstrated that the timing of diagnosis of retained lens fragments and their associated sequelae is highly variable, with some published examples spanning several years.
Currently, there is a paucity of data describing the patient features and clinical outcomes related to management strategies for various types of retained lens fragments in the anterior chamber. The largest identified study to date included only 16 patients and was limited to a diagnosis of retained nuclear lens fragments. We studied the clinical features, treatments, and outcomes of all cases with a diagnosis of retained lens fragment in the anterior chamber and sought to identify patient characteristics associated with lens fragment retention and to describe an association between management decisions and clinical outcomes.
Methods
This study was conducted with the prior approval of the Duke University School of Medicine (Durham, North Carolina, USA) Institutional Review Board (IRB protocol # 43459). The research described herein adhered to the tenets of the Declaration of Helsinki and was compliant with the Health Insurance Portability and Accountability Act (HIPAA). The Duke Eye Center medical record database was searched for various medical and surgical diagnoses, including: “cataract fragment post-op,” “phacoanaphylaxis,” and “lens aspiration.” The search spanned all clinical and operating room visits from January 1, 2007 to January 12, 2013 and included all practitioners within our institution. The medical records of all patients greater than 17 years old and having at least 1 of the qualifying diagnoses (noted above) were reviewed.
Those subjects with a documented history of otherwise uncomplicated phacoemulsification cataract extraction and a clinical examination positive for retained lens fragment in the anterior chamber were included for study. Patients with a history of posterior capsular compromise or combined glaucoma and cataract surgery were excluded. Patients were identified and their charts were reviewed for demographic information, clinical examination findings, ocular biometry measurements, treatment received, and pre– and post–lens fragment removal visual acuity. The best-corrected visual acuity following lens fragment extraction was recorded as best tested vision from all clinical visits ranging from 1 month to 1 year following lens fragment removal. Time to diagnosis of lens fragment and time to surgical removal (if applicable) were also recorded. Slit-lamp photographs and anterior segment optical coherence tomography (OCT) images were obtained for a limited number of patients. Statistical comparison of paired and unpaired mean values was performed using the Student t test with a 2-tailed P value.
Results
A total of 54 eyes of 54 patients were identified with retained lens fragments in the anterior chamber, with baseline characteristics shown in the Table . Overall, the rates of pre–cataract extraction myopia and hyperopia were approximately equal. On subset analysis, 6 of the 22 patients with myopia had a spherical equivalent refraction over 5 diopters, while 3 of the patients had a refraction consistent with high hyperopia. Over 20% of patients had relatively long eyes (axial myopia) with an axial length greater than 25 mm; however, median axial length was 23.6 mm. Six patients from our dataset were missing preoperative refractions and biometry measurements, as their cataract surgery had been performed elsewhere and records were not available.
| Mean age (y) | 75.1 (range 54–89) |
| Female | 22 (40.7%) |
| Pre–cataract surgery refraction a | |
| Myopia | 22 (45.8%) |
| Hyperopia | 21 (43.8%) |
| Emmetropia b | 5 (10.4%) |
| Pre-cataract surgery corneal examination a | |
| Clear | 41 (85.4%) |
| Fuchs | 3 (6.3%) |
| Dense arcus | 4 (8.3%) |
| Axial length a | |
| Mean | 23.8 mm (range 20.6–28.7) |
| <22 mm | 2 (4.3%) |
| >25 mm | 10 (21.7%) |
| Mean anterior chamber depth a | 3.04 mm (range 2.15–3.96) |
| History of Flomax | 4 (8.3%) |
a Preoperative data only available for 48 of 54 patients.
b Emmetropia defined as spherical equivalent ≤0.25 diopters from plano.
The majority (87%) of patients were diagnosed with retained lens fragment on slit-lamp examination ( Figure 1 ); however, 13% of cases required gonioscopy for visualization of the lens fragment ( Figure 2 ). In 1 case, clear visualization of a presumed lens fragment was compromised by associated corneal edema and an anterior segment OCT image was obtained ( Figure 3 ). In all 54 eyes, the retained lens piece was located in the inferior anterior chamber or inferior angle. Sixteen percent of lens fragments were described as “nuclear” on examination, 11% were “epinuclear,” and 22% were “cortical,” while 50% were not qualified and simply noted as “lens fragment.” Eighty-one percent of patients had documented anterior chamber inflammation at the time of diagnosis. At the time of diagnosis, the intraocular pressure ranged from 6 to 40 mm Hg with 11% greater than 25 mm Hg. Two patients had documented cystoid macular edema.
Just under half of all eyes (43%) with a retained lens fragment presented with corneal edema. Seven additional eyes went on to develop corneal edema after the time of diagnosis, for a total of 30 eyes (56%) with corneal edema at any time point. A similar rate of corneal edema (47%) was noted when patients diagnosed with a lens fragment at postoperative day 1 were excluded from analysis. In 60% of all patients with corneal edema (18 of 30), the edema localized to the inferior quadrant. The predilection for inferior edema was even higher (12 of 15, 80%) among patients with corneal edema who were diagnosed with a retained lens fragment after postoperative day 1.
There was a large range in time to diagnosis of retained lens fragment following phacoemulsification ( Figure 4 ). Twenty-two patients (41%) were diagnosed at postoperative day 1. Thereafter, 24 patients (44%) were diagnosed during their routine postoperative period (between day 2 and 2 months postoperatively). Five patients (9%) were diagnosed between 2 and 6 months postoperatively while 3 patients (6%) were diagnosed after 6 months. Two of the 3 patients diagnosed after 6 months post cataract surgery were initially managed by their referring provider as “recurrent iritis,” while the other patient was followed for nearly a year with a diagnosis of nonclearing pseudophakic bullous keratopathy.
