Distribution of pseudoexfoliation material on anterior segment structures in human autopsy eyes after cataract surgery with intraocular lens implantation

Capsule Dynamics, Implantation, and Explantation of the Smaller Incision, New-Generation Implantable Miniature Telescope: a Miyake-Apple Study

PURPOSE

The smaller incision, new-generation implantable miniature telescope is a novel implant to optimize vision in retinal patients with central vision loss. Using Miyake-Apple techniques we visualized the device implantation, repositioning, and explantation, while noting capsular bag dynamics.

METHODS

Using the Miyake-Apple technique, we assessed capsular bag deformation after successful implantation of the device in human autopsy eyes. We assessed rescue strategies for converting a sulcus implantation to a capsular implantation and explantation strategies. We noted the occurrence of posterior capsule striae, zonular stress, and the haptics' arc of contact with the capsular bag after implantation.

RESULTS

Acceptable zonular stress was observed during the successful implantation of the SING IMT. When it was implanted in the sulcus, one could reposition the haptics into the bag with two spatulas using counter-pressure in an effective strategy despite inducing tolerable, medium zonular stress. A similar technique, in reverse, allows safe explantation without damaging the rhexis or the bag, while inducing similar medium, tolerable zonular stress. In all eyes we examined, the implant considerably stretches the bag, inducing a capsular bag deformation and posterior capsule striae.

CONCLUSION

The SING IMT can be safely implanted without significant zonular stress. In sulcus implantation and explantation, repositioning of the haptic is achievable without perturbing zonular stress using the presented approaches. It stretches average-sized capsular bags to support its weight. This is achieved by an increased arc of contact of the haptics with the capsular equator.

Regional variation in the incidence of pseudo-exfoliation in the Andhra Pradesh Eye Disease Study (APEDS)

BACKGROUND

To report the 15-year incidence rate of pseudo-exfoliation (PXF),  PXF glaucoma and regional variation among rural participants in the Andhra Pradesh Eye Disease Study (APEDS) III.

METHODS

This population-based longitudinal study was carried out at three rural study sites. Individuals of all ages who participated at baseline with a mean 15-year follow-up visit were included. Detailed Comprehensive ophthalmic examination was performed on all participants. The main outcome measure was development of PXF during the follow-up period in participants who were phakic in one or both eyes without PXF at baseline.

RESULTS

Among 5395 participants, 5108 (94.6%) met the inclusion criteria. There were 93 (1.82%; 95% confidence interval (CI), 1.47-2.22) cases of incident PXF. Their median baseline age (1st, 3rd quartiles) was 51 (44, 59) years and the male: female ratio was 1.3:1. There was no case of incident PXF in participants aged <30 years at baseline. The incidence rate per 100 person years (95% CI) among all ages and those aged ≥30 years at baseline was 1.73 (1.64-1.82) and 3.73 (3.53-3.93), respectively. PXF material was located on iris as well as anterior surface of lens and it was often bilateral. Participants living in two study sites and increasing age were associated with the incidence of PXF. The 15-year incidence of PXF glaucoma (95% CI) in participants ≥30 years of age at baseline was 0.33% (0.14-0.66).

CONCLUSION

There is significant regional variation in incidence of PXF in south India which warrants further investigation.

Histopathology of Exfoliation Syndrome

Exfoliation syndrome (XFS) is characterized by light and electron microscopy by age-dependent gradual accumulation of whitish material of largely unknown composition and origin along both the anterior and posterior chambers and widely within the iris stroma. These deposits can be fairly specifically labeled with selected antibodies and lectins. Immunohistochemistry shows that intraocular exfoliation deposits share antigens with the microfibrillar elastic fiber system and several basement membrane components, including carbohydrate epitopes on glycosaminoglycans, proteoglycans, and cell adhesion molecules. The earliest histopathologic manifestation of XFS seems to be the deposition of characteristic fibers in various extraocular and anterior segment tissues, as observed by electron microscopy, and perivascular deposition of material within the iris stroma, which is antigenically typical of that found in classic intraocular exfoliation deposits. These findings precede the clinical diagnosis of XFS and likewise can be detected in the seemingly uninvolved fellow eyes of patients with clinically unilateral XFS. Indeed, histopathologic examination of capsulotomy, iridectomy, and trabeculectomy specimens can lead to a clinically unexpected diagnosis of XFS. Exfoliation fibers are additionally found widely distributed in extraocular connective tissues and visceral organs, but the matrix of these fibers seems to differ from that of intraocular deposits. In addition to this histopathologic discrepancy, both the frequent occurrence of clinically unilateral, histopathologically highly asymmetric exfoliation deposits, and the relationship between the early iris vasculopathy that not infrequently may be observed histopathologically for years before classic widespread exfoliation deposits appear along the anterior and posterior chambers remain to be resolved.

Intraoperative and postoperative complications of cataract surgery in eyes with pseudoexfoliation - An 8-year analysis

INTRODUCTION:

Pseudoexfoliation (PXM) is a fibrillar material deposited in the anterior chamber of the eye and can cause disintegration of zonules and make pupillary dilatation difficult. This can make surgery difficult and result in intraoperative and postoperative complications. The aim of this study was to learn about whether the presence of pseudoexfoliation caused significant complications during cataract surgery.

MATERIALS AND METHODS:

We did a secondary data analysis of 12,992 eyes from 2007 to 2014 using the National Eye Database of Melaka Hospital Malaysia on intraoperative and postoperative cataract surgery complications of patients with PXM.

RESULTS:

Patients with PXM were 2.68 times more likely to get intraoperative complications (P < 0.001). They had a higher incidence of lens subluxation, zonular dehiscence, and vitreous loss (P < 0.001). Although posterior capsule rupture (PCR) was the most common intraoperative complication during cataract surgery (4.8%), the presence of pseudoexfoliation was not associated with PCR (P > 0.05). We did not observe any association between patients with pseudoexfoliation and any of the postoperative complications such as corneal decompensation, raised intraocular pressure, and intraocular lens decentration (P > 0.05). Pseudoexfoliation did not cause corneal decompensation (P > 0.05) although corneal decompensation was the highest postoperative complication of cataract surgeries (0.18%).

CONCLUSIONS:

Patients with PXM had a higher rate of intraoperative complications which were mainly vitreous loss and zonular dehiscence and also lens subluxation/dislocation. We observed poorer visual outcomes in those with PXM following cataract surgery. Patients with pseudoexfoliation should be identified and precautions taken to minimize these complications to get better visual outcomes.

Isoforms of TGF-β in the aqueous humor of patients with pseudoexfoliation syndrome and a possible association with the long-term stability of the capsular bag after cataract surgery

BACKGROUND

Pseudoexfoliation syndrome (PEXS) may go along with capsular bag shrinkage and luxation. In the present study, we focus on an association of isoforms of TGF-β with capsular bag luxation.

METHODS

Aqueous humor was collected intraoperatively from 20 healthy controls and from 73 otherwise healthy patients with PEXS [PEXS without complications (PEX, n = 33), late PEXS with glaucoma (PEXG, n = 30) and with IOL and capsular bag luxation (PEXL, n = 10)]. The concentrations of TGF-β1, TGF-β2 and TGF-β3 were compared using the Bio-Plex® multiplex beads system based on the non-parametric Kruskal-Wallis H test (p < 0.01).

RESULTS

Concentrations of TGF-β 1, TGF-β 2 and TGF-β 3 were higher in the sub-groups PEX and PEXG than in controls (TGF-β 1; p = 0.009 and 0.0005; TGF-β 2; p = 0.002 and 0.005 and TGF-β 3; 0.0005 and 0.0005; respectively), whereas for TGF β2, no significant difference between controls and PEXL was revealed (p = 1.0). TGF-β2 concentrations were elevated in a similar degree in early PEX and PEXG, but not in PEXL compared to controls (p = 0.002). The concentrations of of TGF-β 1 and TGF-β 3 increased in parallel with the progression of disease. The levels of TGF-β 3, however, did not attain pathophysiological levels (>100 pg/ml) in any group.

CONCLUSIONS

A stage-dependent increase in the concentrations of TGF-β1 and TGF-β3, but not of TGF-β2, accords to the shrinkage of the capsular bag. This could increase the tension on the zonular fibers and contribute to luxation of the capsular bag.