Capsular Bag Contraction Research Articles

Three-Dimensional Assessments of Intraocular Lens Stability With High-Speed Swept-Source Optical Coherence Tomography.

To evaluate the effect of intraocular lens (IOL) optic overlapping on IOL stability and to determine the relationship between the capsulorhexis and IOL movement with the three-dimensional method of swept-source optical coherence tomography (SS-OCT). This study identified patients with age-related cataracts and divided them into two groups according to their anterior capsule and IOL optic relationship: total anterior capsule overlap (360°) and partial anterior capsule overlap (< 360°). Standard SS-OCT radial scanning was performed in all eyes at 1 day, 1 week, 1 month, and 3 months after cataract surgery, respectively. The obtained photographs were used for the postoperative position measurements of capsulorhexis and IOL after three-dimensional reconstruction. This study included 46 eyes of 34 patients: total overlap group (n = 29) and partial overlap group (n = 17). The postoperative aqueous depth significantly decreased in the first week after surgery (P < .001). The IOL tilt was greater in the partial overlap group than that in the total overlap group (P = .014). The IOL moved significantly in the first week postoperatively (both P < .001). IOL decentration in the x-axis was greater in the partial overlap group than that in the total overlap group (P = .024). The IOL and capsulorhexis both moved sharply in the first week (both P < .05). The IOL moved consistently with the capsulorhexis in the 3 months after surgery (all P > .05). The total overlap group showed better IOL centrality and stability. IOL movement may be driven by capsular bag contraction and fibrosis. Thus, it was demonstrated that postoperative IOL position and IOL performance were closely linked with proper size of central continuous curvilinear capsulorhexis. [J Refract Surg. 2020;36(6):388-394.].

Preliminary report on the application of femtosecond laser-assisted anterior capsulotomy in intumescent white cataract surgery

Objective: To assess the effect of femtosecond laser-assisted anterior capsulotomy in intumescent white cataract surgery. Methods: Retrospective case series study. One hundred and fifty cataract patients (150 eyes) from June 2014 to June 2015 in Wuhan Aier ophthalmology hospital were enrolled in this study. They were divided into three groups: 50 intumescent white cataract patients (50 eyes) in the study group were performed femtosecond laser-assisted capsulotomy (LenSx system) operation selectively. Fifty intumescent white cataract patients (50 eyes) underwent normal manual continuous circular capsulorhexis as the control group 1. Fifty other types cataract patients (50 eyes) underwent femtosecond laser-assisted capsulotomy as the control group 2. To observe the complications such as radial tear in anterior capsule, posterior capsule rupture and vitreous prolapse occurred during operations in each group respectively. The microscopic images of the free anterior capsule after dyeing were observed in the studygroup and the control group 2. Using the German company Oculus Pentacam three-dimensional anterior eye segment system to collect the Scheimplug images of each group at 1, 3, 6 months and 1 year after operation. The data were analyzed by SPSS19.0 software package. Complications during operations in all groups were compared with Fisher exact test. The eccentricity and tilt of IOL in each group were analyzed by single factor analysis of variance. The SNK-q test was used to compare the different follow-up time groups. Results: One hundred and fifty patients aged from 50 to 86 years old, including 72 male cases and 78 female cases. In study group, radial tear in anterior capsule occurred in 2 eyes (4%), adherent tongue-like capsule adhesion was found in 6 eyes (12%), incomplete capsulotomy button happened in 2 eyes (4%), and posterior capsule rupture and vitreous prolapse occurred in 1 eye (2%). In the control group 1, radial tear in anterior capsule occurred in 8 eyes (16%) and posterior capsule rupture and vitreous prolapse occurred in 3 eyes (6%). The cases number of radial tear in anterior capsule and posterior capsule rupture and vitreous prolapse in the study group was obviously lower than the control group 1. The difference was statistically significant (P<0.05). In the control group 2, all 50 eyes were successfully completed. The implantation was uneventful and the IOL was centered. And posterior capsular rupture and vitreous prolapse did not occur. The difference was statistically significant between the study group and the control group 2 (P<0.05). After 1 year follow-up, the study group and the control group 2 showed no significant IOL tilt and eccentricity. The eccentricity and tilt of IOL in horizontal and vertical direction in control group 1 were significantly higher than those in the study group (F was 2.31, 1.10, 2.78 and 2.90 respectively) and control group 2 (F was 2.50, 2.32, 2.56 and 2.18respectively). The difference was statistically significant (P<0.05). Conclusions: Femtosecond laser-assisted anterior capsulotomy is accurate circle and center to avoid IOL eccentricity and tilt caused by capsular bag contraction asymmetrically after implantation, so as to ensure the long-term stability of the visual quality postoperatively. (Chin J Ophthalmol, 2017, 53: 281-287).

The clinical effect of Nd: YAG laser anterior capsulotomy for the treatment of capsular bag contraction syndrome

Objective To observe the clinical effect of Nd: YAG laser anterior capsulotomy for the treatment of capsular bag contraction syndrome(CCS) after intraocular lens implantation. Methods Eighty-five eyes of 85 cases of CCS were treated with Nd: YAG laser anterior capsulotomy. The minimum diameter of the anterior capsule opening, best corrected visual acuity(BCVA), corneal endothelial count and intraocular pressure (IOP) were observed 1 day preoperation and 1 week postoperation. The follow-up time was 6 months. Results The contractile ring of anterior capsule opening was opened and the contraction of capsule bag was released after Nd: YAG laser anterior capsulotomy. No serious complication was observed. The number of the eyes with BCVA≥0.3 was increased from preoperative 43 eyes to postoperative 52 eyes. The minimum diameter of the anterior capsule opening increased significantly, form (1.91±1.52)mm to (4.33±1.92)mm (t=7.45, P=0.00). No significant change in corneal endothelial cell counts after treatment was observed, (2304±202)/mm2vs (2281±234)/mm2 (t=1.03, P=0.15). IOP did not change significantly 1week postoperation compared to 1day preoperation, (15.53±4.34)mmHg vs (15.76±4.49) mmHg (t=0.62, P=0.27). No IOL shift was observed during 6 months follow-up. Conclusion Nd: YAG laser anterior capsulotomy is an effective treatment for CCS. No serious complication was observed after early surgical treatment. Key words: Cataract; Capsule contraction syndrome; Laser anterior capsulotomy; Intraocular pressure

Late capsular bag contraction and intraocular lens subluxation in retinitis pigmentosa: a case report

IntroductionRetinitis pigmentosa is clinically characterized by loss of predominantly rod photoreceptor function as well as loss of peripheral vision. The classic clinical triad is considered to be the presence of bone spicule pigmentation in the peripheral retina, arteriolar attenuation, and waxy disc pallor. Cataracts, most commonly of the posterior subcapsular type, are often found in all forms of retinitis pigmentosa. Ectopia lentis and lens dislocation are known risk factors for those with retinitis pigmentosa, presumably secondary to zonular fiber weakness and vitreous degeneration. The post-operative complication of lens dislocation following cataract extraction in patients with retinitis pigmentosa has also been documented.Case presentationWe report a case of severe capsular bag contraction with intraocular lens subluxation following cataract extraction in a 58-year-old Hispanic woman with retinitis pigmentosa.ConclusionPatients with retinitis pigmentosa undergoing cataract surgery should be notified of this potentially late complication of surgery.

The influence of injection volume and capsular bag contraction on the refractive power of polymer refilled lenses - a finite element modelling simulation study

Polymer injection into the capsular bag after phakoemulsification is an interesting and promising approach to lens surgery. Safe clinical application of this technique will require an appropriate estimate of the effect of implantation variables on the lens power. This article details the results of finite element investigations into the effects of the injected polymer volume and capsular bag contraction on the resultant lens power and accommodation amplitude. An axisymmetric finite element model was created from literature sources. Polymer injection and the capsular contraction were simulated, and their effect on the lens power was calculated. The simulations show that overfilling during polymer injection leads to a refractive power increase of the lens. Capsular bag contraction also results in a power increase. The calculated accommodative amplitude of the lens is minimally affected by capsular bag contraction but decreases significantly with increased capsular bag stiffness as a result of fibrosis.

Pathological evaluation of postmortem human eyes implanted with a new single-piece hydrophobic acrylic lens

Purpose: To report the pathological findings in 14 human cadaver eyes implanted with a single-piece AcrySof® (Alcon Laboratories) posterior chamber intraocular lens (IOL). Setting: David J. Apple, MD Laboratories for Ophthalmic Devices Research, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Methods: Fourteen human autopsy eyes implanted with a single-piece AcrySof (SA30AL) IOL were evaluated. The eyes were sectioned at the equatorial plane, and the anterior segment containing the IOL in the capsular bag was evaluated from a posterior perspective (Miyake-Apple view) and from an anterior perspective (surgeon's view) after removal of cornea and iris. They were then processed through paraffin, sectioned, and stained with hematoxylin–eosin, periodic acid-Schiff, and Masson's trichrome and examined under light microscopy. Results: All IOLs had symmetric in-the-bag fixation. Slight decentration was measured in 1 eye, which also had an anterior capsule tear. Grade 1 anterior capsule opacification was present in 9 eyes. No central posterior capsule opacification or posterior capsule folds were observed in any eye. Soemmering's ring formation was observed in 5 eyes. Zonular stretch caused by different degrees of capsular bag contraction was present in 4 eyes without decentration of the IOL. Conclusions: Analyses of pseudophakic cadaver eyes from the posterior (Miyake-Apple) view, complemented by microscopic analyses, proved useful in the evaluation of IOL–capsular bag interaction. These studies are more important in cases of newly introduced lens designs.

Do three-piece PMMA IOLs rotate after implantation in the capsular bag?

With the current interest in toric intraocular lenses (IOLs), it is critical to establish whether these implants rotate following cataract surgery. If there is continual rotation of the implant with capsular bag contraction, then the orientation of the astigmatic correction would be unstable and thus not clinically useful. Twenty-eight eyes were followed for up to 6 months postoperatively. These consecutive eyes were selected on the basis of demonstrating adequate dilation following surgery, such that the points of haptic to optic insertion could be visualized with the slit-lamp microscope. Sequential photographs and comparisons of the orientation of the lenses postoperatively were performed. With the exception of one lens implant, none of the 28 IOLs demonstrated significant rotation. Of the 16 eyes followed for 6 months, none demonstrated rotation of greater than 4 degrees, which was within experimental error. Continued rotation of PMMA IOLs following implantation in the capsular bag seldom occurs. Thus, the concept of toric IOLs appears to be quite usable.