Trypan blue staining of anteriorly placed zonules in patients with pigment dispersion

Phacoemulsification in eyes with long anterior zonules

PURPOSE

To study the safety of phacoemulsification in eyes with long anterior zonules (LAZs).

SETTING

Institute.

DESIGN

Retrospective interventional case series.

METHODS

All patients with clinically proven LAZs who had undergone phacoemulsification by a single surgeon from January 2014 to December 2018 were included. All cases of LAZs with cataract extraction by procedures other than phacoemulsification or combined with any other ocular surgery were excluded. Sixty-five eyes of 52 patients were analyzed. Phacoemulsification with capsulorhexis that involves sacrificing the LAZs was performed. The primary outcome measures were the incidence of capsulorhexis extension or the need to rescue intraoperatively and the rate of intraoperative complications. Secondary outcomes assessed were the percentage of eyes within ±0.5 diopters (D) and ±1 D of the target refraction.

RESULTS

Sixty-five eyes (52 patients) were analyzed; the mean age of patients was 67.3 ± 7.4 years. The successful completion of an adequately sized capsulorhexis without extension or rescue was seen in 100% of cases. The incidence of intraoperative complications was 1.5% (posterior capsular rupture in 1 eye). The mean postoperative corrected distance visual acuity was 0.05 ± 0.1 (logarithm of the minimum angle of resolution) at a mean of 26.8 ± 7.6 days. The mean spherical equivalent was -0.15 ± 0.7 D. Eyes within ±0.5 D and ±1.00 D of the target refraction were 77% and 94%, respectively.

CONCLUSIONS

Phacoemulsification in eyes with LAZs can be safely performed through an adequately sized capsulorhexis by sacrificing, ie, cutting or breaking, the anteriorly inserted zonules 360 degrees without significant intraoperative complications.

Krukenberg's Spindles Strongly Suggest Long Anterior Zonule Associated Pigment Dispersion Mechanism in Older Patients

Purpose

The purpose of this study was to further investigate factors associated with Krukenberg’s spindle (KS) presence in a primary eye care setting.

Methods

As part of a larger investigation, several practitioners in an academic eye care facility in Chicago, IL, USA evaluated patients for the long anterior zonule (LAZ) trait during 2011 to 2018, and data were collected on ocular/systemic health, lifestyle, and demographic variables, including the presence of a KS. Multivariate regression was used to assess relationships to KS presence.

Results

Analysis included 3501 subjects with mean age of 51 ± 15 years (18–98 years; 65% women; and 84% African American). Among the right eyes, 57 (1.6%) had a KS, with this group having a mean age of 62 ± 13 years (25–86 years; 75% women; and 82% African American). There were 120 subjects (3.4%) with right eye LAZ, with mean age of 64 ± 11 years (36–91 years; 77% women; and 92% African American). There were 19 of 57 (33.3%) KS eyes that also had LAZ. Controlling for other factors, variables with the strongest relationship to KS presence were the LAZ trait (odds ratio [OR] = 12.2, 95% confidence interval [CI] = 6.5 to 22.8, P < 0.0001) and advancing age (OR = 1.3 per decade, 95% CI = 1.3 to 1.9, P < 0.0001).

Conclusions

In the population studied, KS presence had its strongest relationship to the LAZ trait and advancing age. The KS-LAZ relationship may not be well-known, but these data strongly suggest that pigment dispersion signs, such as a KS, should prompt the clinician to consider the LAZ trait as a potential etiology, especially because LAZ is associated with higher IOP and possibly glaucoma.

Cataract surgery in patients with late-onset retinal degeneration

PURPOSE

To review the outcomes in a series of patients with long anterior lens zonular fibers associated with late-onset retinal degeneration who had phacoemulsification cataract surgery.

SETTING

Newcastle Eye Centre, Newcastle upon Tyne, United Kingdom.

DESIGN

Retrospective case series.

METHODS

Inclusion criteria were patients with genetically confirmed late-onset retinal degeneration requiring cataract surgery. Perioperative data relating to surgery were collected. In addition, the corrected distance visual acuity (CDVA) and retinal imaging data were recorded. Selected lens capsules were examined using immunohistochemistry or scanning electron microscopy (SEM).

RESULTS

Eleven eyes of 7 patients were included. The long anterior lens zonular fibers made capsulorhexis challenging; however, it was completed safely in all cases. There were no intraoperative or postoperative issues with lens stability. The CDVA improved postoperatively in those cases with intact foveal photoreceptors and retinal pigment epithelium. Over the longer term, the CDVA slowly declined because of progressive atrophy of the macula. Most patients noticed a subjective improvement in vision, even those with advanced disease at baseline. Immunohistochemistry showed that the C1QTNF5 protein was expressed within the lens capsule epithelial cells, although SEM of the long anterior lens zonular fibers showed them to be smaller in diameter than normal anterior lens zonular fibers and to be composed of a helix of fibers.

CONCLUSIONS

In this small series of patients with late-onset retinal degeneration, cataract surgery was successfully performed without long-term complications involving intraocular lens stability. The objective improvement in CDVA seemed to be limited to patients with good foveal photoreceptor architecture.

Long Anterior Lens Zonules and Intraocular Pressure

Purpose

To investigate the relation between intraocular pressure (IOP) and the idiopathic long anterior zonule (LAZ) trait.

Methods

Patients presenting for primary eye care were examined for LAZ, identified as radially oriented zonular fibers with central extension >1.0 mm beyond the normal anterior lens insertion zone (estimated via slit lamp beam length). Ocular, systemic health, and lifestyle data were collected via comprehensive exam and questionnaire. Multivariate regression was used to assess the relationship between IOP (Goldmann) and LAZ.

Results

There were 2169 non-LAZ and 129 LAZ subjects (mean age: 49.8 ± 15.0 vs. 62.6 ± 10.2 years; 63.6% vs. 76.0% female; 83.2% vs. 91.5% African American). Right eyes with >trace LAZ (n = 59 of 110) had higher unadjusted mean IOP than control eyes (16.4 ± 3.3 vs. 15.0 ± 3.3 mm Hg, P = 0.005), and with control for numerous factors, LAZ eyes had an average IOP of approximately 1.3 ± 0.4 mm Hg higher (P = 0.003) than non-LAZ eyes. Final model covariates included sex (P = 0.001); spherical-equivalent refractive error (D; P < 0.0001); body mass index (kg/m²; P < 0.001); presence of diabetes (P < 0.001); having >high school education (P < 0.001); systolic blood pressure (mm Hg; P < 0.0001); being an ever smoker (P = 0.006); and having history of any site cancer (P = 0.01).

Conclusions

The LAZ trait, with potential prevalence near 2%, was associated with a higher IOP. This observation is consistent with the hypothesis that the trait is a marker for underlying mechanisms that elevate glaucoma risk.

Morphologic Patterns Formed by the Anomalous Fibers Occurring Along the Anterior Capsule of the Crystalline Lens in People With the Long Anterior Zonule Trait

People with the long anterior zonule (LAZ) trait, which may have prevalence near 2%, have zonular fibers that extend more central than usual along the anterior capsule of the crystalline lens. The anomalous fibers can be observed in vivo with clinical slit lamp biomicroscopy after pharmacologic pupil dilation, and although minimally studied, the LAZ trait may have importance to glaucoma, retinal degeneration, and cataract surgery. To further characterize LAZ morphology, a custom computer program was used to trace LAZ fibers seen on retro-illumination photos acquired during previous study at an academic, urban eye care facility in Chicago, IL. There were 59 African-Americans (54 female; median age = 70 years, 53-91 years) included in the analysis. After initial review of the zonule tracings, we identified three basic LAZ patterns. We called one pattern (47% of right eyes) a "non-segmental LAZ pattern," which was predominated by fibers that could be visually traced to the dilated pupil border where they became obscured by the iris. Another pattern (35% of right eyes), the "segmental LAZ pattern," was predominated by fibers that appeared to terminate abruptly without detectable extension to the pupil border. The third pattern (18% of right eyes), the "mixed LAZ pattern," had a more equivalent mixture of the other two fiber morphologies. Compared to the "non-segmental" group, the "segmental" LAZ eyes had smaller central zonule-free zones (P < 0.0001), and they tended to exhibit fewer LAZ fibers (P = 0.07). These data improve understanding of LAZ clinical anatomy and may be helpful to future investigation. Anat Rec, 300:1336-1347, 2017. © 2017 Wiley Periodicals, Inc.

Anterior Chamber Depth, Lens Thickness, and Related Measures in African American Females With Long Anterior Zonules: A Matched Study With Control for Refractive Error

PURPOSE

To investigate anterior chamber depth (ACD), lens thickness (LT), vitreous body length (VBL), and axial length (AL) in African American females with long anterior zonules (LAZ) while controlling for refractive error.

METHODS

The eyes of 50 African American females with LAZ were compared with 50 controls matched with age, race, sex, and refractive error. Central ACD, LT, VBL, and AL measurements were obtained in a masked manner using a-scan ultrasonography.

RESULTS

LAZ cases had a mean age±SD of 67.1±7.6 years (range, 52 to 85 y) and a mean refractive error of +1.85±1.41 D (-1.75 to +4.75 D). Parameters were similar for controls. Mean ACD for cases was 2.45±0.34 mm and 2.57±0.38 mm for controls. Mean LT for cases was 4.94±0.43 mm and 4.83±0.45 mm for controls. Mean VBL for cases was 15.00±0.72 mm and 15.17±0.76 mm for controls. Mean AL for cases was 22.39±0.82 mm and 22.57±0.76 mm for controls. Using multiple logistic regression to control for any residual differences in age and refractive error, no significant differences were present between LAZ eyes and control eyes relative to the a-scan variables (P>0.1).

CONCLUSIONS

When refractive error was controlled for, this group of African American females with LAZ did not exhibit clinically significant differences in ACD, LT, VBL, and AL as compared with controls.