Capsular Bag Shrinkage Research Articles

Application of capsular bag relaxation for capsular contraction syndrome.

The present study analyzed the surgical method and clinical effects of capsular bag relaxation surgery (CBRS) for the treatment of capsular contraction syndrome (CCS), which usually occurs post-phacoemulsification. The retrospective case study comprised of a total of 25 patients (25 eyes) who developed CCS after phacoemulsification and subsequently underwent CBRS. Among these patients, 15 patients (15 eyes) received actinoid relaxing incisions and 10 patients (10 eyes) underwent a second continuous curvilinear capsulorhexis. Postoperative naked-eye visual acuity was determined and compared with preoperative naked-eye visual acuity. Size changes of the transparent zone of the anterior capsule opening were observed under a slit lamp, as well as the anterior and posterior capsular membrane conditions and position of the intraocular lens (IOL). In addition, the presence of any subjective symptom, including glare or monocular diplopia, was investigated. A final 6-month postoperative follow-up was conducted for each patient. Visual acuity of all operated eyes improved to various extents. Notably, glare and monocular diplopia were no longer evident and patients could observe things clearly. Visual differences pre- and post-surgery were statistically significant (u=5.143, P<0.01). In addition, capsular bag shrinkage and relaxation were revealed under a slit lamp, the area of the transparent zone of the anterior capsule opening was expanded and the IOL remained centered. To conclude, CBRS is an effective treatment method for patients with CCS who are not suitable to receive laser treatment.

Spontaneous IOL Dislocation - What Can We Do for Prevention?

IOL dislocation and opacification represent further complications of modern IOL (intraocular lenses) implantation. Currently, an increase of IOL dislocation due to various reasons is observed. Due to capsular bag shrinkage, especially in patients with pseudoexfoliation (PEX) and other ocular condition, there is an increasing tension of the weakened zonula. The only use of capsular tension ring (CRT) is not sufficient. The shrinkage of the capsular bag and increasing tension of the zonula may be reduced by additional anterior capsule incisions. The IOL should, preferably, be fixated retrogradely in cases of zonula weakness, even in the case of a weakened capsular bag or minor intraoperative zonulysis, to prevent later IOL dislocation. The effectiveness of these interventions should be examined in larger studies in the future.

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.

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. 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). 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 (>100pg/ml) in any group. 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.

Intraindividual Capsular Bag Shrinkage Comparing Standard and Laser-Assisted Cataract Surgery

To examine the dynamics of capsular bag changes over 3 months of healing after standard cataract surgery and laser-assisted cataract surgery. One hundred six eyes of 53 patients with visually significant cataracts were treated with laser-assisted cataract surgery in one eye and standard phacoemulsification in the other. A capsular measuring ring was implanted in both eyes and effective phacoemulsification time was recorded. Capsular bag diameter was measured at six time points within 3 months of follow-up. Intraindividual capsular bag shrinkage was calculated. The laser group required less ultrasound energy to remove the softened nucleus than the standard group (effective phacoemulsification time: 0.03 vs 1.25 sec; P < .005). The laser group had statistically significantly less capsular bag shrinkage than the standard group at all time points from 1 to 3 months (P < .001). Lens position changes within 3 months postoperatively may be lessened with laser-assisted cataract surgery in comparison to standard phacoemulsification due the decreased capsular bag shrinkage during this period. A tendency toward earlier stabilization of the capsular bag diameter with laser-assisted cataract surgery provides potential for more predictable effective lens position and intraocular lens power calculations.

Effect of a closed foldable equator ring on capsular bag shrinkage in cataract surgery

Effect of a closed foldable equator ring on capsular bag shrinkage in cataract surgery

Effect of a closed foldable equator ring on capsular bag shrinkage in cataract surgery

To evaluate the effect of a closed foldable equator ring (CFER) versus a conventional capsular tension ring (CTR) on capsular bag shrinkage. Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. In this prospective study, 70 eyes of 70 patients were randomized to 2 groups using a 1:1 block scheme. After uneventful cataract surgery, a capsular measuring ring was implanted in all eyes to measure the capsular bag diameter in vivo. In Group 1, a CTR was implanted in the capsular bag. In Group 2, a CFER was inserted. Biometric characteristics such as axial length and the horizontal and vertical corneal radii were measured preoperatively. The capsular bag diameter and capsulorhexis diameter were measured intraoperatively and 2 or 3 days as well as 1 and 3 months postoperatively. There were no statistically significant or clinically relevant between-group differences in covariants such as axial length, vertical and horizontal corneal radii, and capsulorhexis diameter. Eyes with the CTR had slight but statistically significant capsular bag shrinkage from a median of 10.4 to a median of 10.2 mm after 3 months (P<.001). Eyes with the CFER also had slight but statistically significant capsular bag shrinkage from a median of 10.3 to a median of 10.2 mm 3 months postoperatively (P = .021). At baseline, the CTR group had a larger capsular bag diameter, but there were no statistically significant differences between the groups at the 3-month follow-up (P = .669). No clinically relevant capsular bag shrinkage was observed after implantation of a CFER or a CTR. The expected capsular bag shrinkage was the same in both groups.

Capsular bag shrinkage after implantation of a capsular bending or capsular tension ring

To evaluate the influence of a capsular bending ring (CBR) or tension ring (CTR) on capsular bag shrinkage. Department of Ophthalmology, Johannes Gutenberg-University, and Department of Medical Biometry, Epidemiology and Informatics, University of Mainz, Mainz, Germany. In 92 eyes of 92 patients, a capsular measuring ring (CMR) was implanted after phacoemulsification to measure capsular bag size in vivo. Patients were randomized into 3 groups: The first received a CMR and CBR, the second received a CMR and CTR, and the third received a CMR alone. Measurements were performed preoperatively, intraoperatively, during the first 3 postoperative days, and after 1 and 3 months. Preoperative biometric characteristics such as axial length (AL) and anterior chamber depth were determined. Primary clinical end points were capsular bag size and capsulorhexis diameter measured intraoperatively and by means of slitlamp biomicroscopy and retroillumination photography postoperatively. There were no clinically relevant group differences in AL, anterior chamber depth, or capsulorhexis diameter. Eyes implanted with the CBR showed shrinkage of the capsular bag from 10.6 to 10.4 mm after a median of 3 months (sign test; P = .023); eyes with a CTR showed comparable median capsular bag shrinkage from 10.5 to 10.2 mm (P<.001), whereas eyes without a CTR showed a median shrinkage from 10.5 to 10.0 mm (P<.001). Intraindividual shrinkage was of a similar, although significantly different, order among these groups (median shrinkage 0.15 versus 0.23 and 0.38 mm, respectively; all pairwise Wilcoxon test; P = .050, P = .020, P<.001, respectively). Capsular shrinkage can be inhibited by a CBR and, to lesser extent, a CTR; the gain in shrinkage prevention is limited when compared with a CMR, however. This conclusion can be drawn only for the specific CBR or CTR and hydrophobic acrylic intraocular lens (IOL) used in this study. Reduction of capsular bag shrinkage after CTR implantation may reduce IOL dislocation and tilt and help to maintain postoperative visual acuity.

Spring constants of capsular tension rings

To determine the spring constants of several types of capsular tension rings (CTRs). Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. Fourteen models of CTRs provided by 9 companies were tested; all were 11.0 mm in diameter. The CTRs were positioned in a special retainer of a material-testing machine and compressed at a constant speed of 10.0 mm per minute. The distance and force values were recorded, and each CTR model was tested 3 times using a new specimen each time. The resulting measurements were used to calculate a mean spring constant for each CTR model. All tested CTRs showed linear proportionality between force and compression distance. Test results were repeatable and precise. Capsular tension rings of the same model had comparable mechanical properties, and different models had different mean spring constants ranging from 0.8162 to 4.5501 mN/mm. The spring constant of a CTR is a suitable mechanical characteristic to facilitate the choice of CTR model. A CTR with a low spring constant may be advantageous for the management of zonular dialysis, whereas a CTR with a higher spring constant may reduce capsular bag shrinkage more effectively.

Capsule measuring ring to predict capsular bag diameter and follow its course after foldable intraocular lens implantation

Purpose: To evaluate the extent of capsular bag shrinkage after cataract surgery with intraocular lens (IOL) implantation and develop a regression formula to predict postoperative capsular bag size. Setting: Eye Hospital, Johannes Gutenberg-University, Mainz, Germany. Methods: The axial length (AL), anterior chamber depth, and corneal radius in 58 eyes were measured preoperatively. Cataract surgery was by phacoemulsification followed by implantation of a 3-piece, acrylic, posterior chamber IOL. The capsular bag diameter and anterior capsulorhexis were measured intraoperatively and 1 day and 1, 3, and 6 months postoperatively using a Koch capsule measuring ring (HumanOptics). Results: The mean capsular bag size was 10.53 mm intraoperatively, 10.31 mm at 1 day, 9.62 mm at 1 month, 9.07 mm at 3 months, and 9.01 mm at 6 months. The mean capsular bag shrinkage over the entire postoperative period was 14.8% ( P<.001). Of the parameters studied, only AL had a positive correlation with capsule shrinkage. The correlation was moderate but statistically significant ( P = .001). Conclusions: A correlation was found between capsular bag shrinkage and AL. Using preoperative biometric data, a regression formula of moderate validity was determined to predict capsular bag shrinkage.

Intracapsular ring sustained 5-fluorouracil delivery system for the prevention of posterior capsule opacification in rabbits: A histological study

Purpose: To evaluate the efficacy of an intracapsular ring releasing 5-fluorouracil (5-FU) in preventing posterior capsule opacification (PCO) in rabbit eyes. Setting: Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA, and Chu Morvan, Department d’Ophtalmologie, University of Brest, France. Methods: Seventeen rabbits were divided into 3 groups: Group 1, 6 rabbits (6 eyes), had phacoemulsification only (control group); Group 2, 6 rabbits (6 eyes), had phacoemulsification with implantation of an open-loop hydrogel intracapsular ring; Group 3, 5 rabbits (5 eyes), had phacoemulsification with implantation of a ring with sustained release of 0.25 μg/h of 5-FU for 9 days. All eyes were followed for 8 weeks before enucleation. Capsular bag shrinkage and the position of the intracapsular ring were assessed, and central and peripheral PCO was evaluated for intensity and area by stereomicroscopy from a posterior (Miyake-Apple) view. The residual equatorial lens epithelial cells (LECs) were counted by the same observer in histological sections. Transmission electron microscopy (TEM) of the cornea, capsular bag, and retina was done to evaluate the toxicity of 5-FU. Results: No significant difference was seen in the degree of capsular bag shrinkage in the 3 groups. The intracapsular ring was decentered in 2 eyes (1 each in Groups 2 and 3). There was a statistically significant difference ( P < .05, Student t test) between Group 1 and Groups 2 and 3 in the area and intensity of central PCO. There was no difference between Groups 2 and 3 in the intensity of central PCO. No evidence of 5-FU toxicity to intraocular structures (cornea, capsular bag, and retina) was demonstrated on TEM analysis. Conclusion: Implantation of an intracapsular ring may prevent central PCO after cataract surgery by mechanically blocking LEC migration toward the central visual axis. The potential pharmacological effect of 5-FU in PCO prevention was not demonstrated.

Capsular bag shrinkage after implantation of an open-loop silicone lens and a poly(methyl methacrylate) capsule tension ring

Purpose: To quantify the dynamics of capsular bag shrinkage after cataract surgery.Setting: University Eye Hospital, Vienna, Austria.Methods: Nineteen eyes in 13 patients had clear corneal cataract surgery with implantation of a foldable, open-loop, silicone posterior chamber intraocular lens (IOL) (AMO SI-30). At the same time, an open, poly(methyl methacrylate) capsule tension ring (Morcher type 14 or 14A) was inserted to allow measurement of capsular bag circumference and diameter. After surgery, capsular bag shrinkage was quantified by measuring anterior chamber depth (ACD), iris-lens distance (ILD), and distance between the eyelets of the capsule tension ring using optical methods. Capsular bag circumference (CBC) was deduced from these measurements, which were taken 1 day (baseline), 1 week, and 1 and 3 months postoperatively.Results: Between 1 day and 3 months, all three parameters decreased significantly. During the first postoperative week, ACID and ILD did not change, while both parameters decreased between 1 week and 1 month. After 1 month, ACID did not decrease further; ILD continued to decrease. The CBC decreased during the entire postoperative period.Conclusion: Besides ACID and ILD, CBC significantly decreased during the first 3 months after cataract surgery with in-the-bag posterior chamber IOL implantation. The CBC can be calculated from the distance between the ends of the capsule tension ring, which can be measured gonioscopically. From this, the diameter of the capsular bag can be calculated in the living eye. The influence of the capsule tension ring itself on capsular bag shrinkage remains to be established.

Suitability of the open loop lens Phacoflex XI-30 for capsular sick implantation by self-sealing sclerocorneal tunnel incisions

We studied a new intraocular lens implant with a high-refractive silicone optic and prolene C-loops. Suitability for folding and implantation with the recommended instruments as well as its performance as a capsular bag implant were evaluated. The impact of the self-sealing wound construction used on postoperative corneal stability was also studied. We included 35 consecutively operated eyes. Capsulorhexis and phacoemulsification were performed. A well-centered and round 4-5 mm anterior capsular opening was aimed at. Using the Fine Universal or the Livernois-McDonald folder the optic was folded lengthwise and the leading loop tucked within the crease. The lens was implanted through a self-sealing sclerocorneal tunnel which measured 3.0 mm in length and 3.2 mm in width. With the instrumentation described, a 3.2 mm incision was adequate. - The lens centered well. In one case each decentration resulted from an optic-edge-by-rhexis-rim capture with an inappropriately shaped rhexis and from excessive capsular bag shrinkage with a too small rhexis. As a rule, the posterior capsule was distended and, with five exceptions, firmly attached to the optic. Fibrosis had resulted in only two cases where the rhexis had evaded the optic edge. Except for a single case where a filtering procedure had been simultaneously performed, optic-to-iris clearance was pronounced in all cases. Consequently, signs of iris chafing were never seen and iridocapsular synechiae had never formed in the latter. - Typically, fine granules scattered within the material and a bluish-violet tint were noted. However, neither intensive haze nor brownish discoloration as well as shell- or inner contour-phenomena were never present. - Vector analysis showed a negligible initial astigmatic shift against the wound that did not progress further on. This new implant performs very satisfactory. It may be even further improved by eliminating the granular inclusions and increasing the haptic rigidity. In order to prevent fibrotic opacification of the posterior capsule full circular overlap of the optic periphery by the anterior capsular leaf should be aimed at. The advantage of the reduced incision width required for insertion makes it very appropriate for clear corneal incision surgery.