Tension Ring Research Articles

Effect of a capsular tension ring on axial intraocular lens position.

To assess the effect of a capsular tension ring (CTR) on the postoperative anterior chamber depth (ACD). Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria. Prospective observer- and patient-masked randomized trial. Bilateral small-incision cataract surgery with implantation of a hydrophobic acrylic single-piece intraocular lens (IOL) (Tecnis ZCB00) was performed using a standard technique. Each patient received a CTR in 1 eye (CTR group) and no CTR in the fellow eye (control group). The ACD was measured preoperatively with biometry (IOLMaster 500) and at 1 hour and 12 weeks postoperatively using partial coherence interferometry (ACMaster). The subjective refraction was assessed at 12 weeks. Sixty eyes (30 patients) were included. Preoperatively, the mean axial length was 23.36 mm ± 1.55 (SD) (range 21.01 to 29.46 mm) in the CTR group and 23.37 ± 1.70 mm (range 21.14 to 28.84 mm) in the control group and the mean ACD was 3.06 ± 0.45 mm (range 2.25 to 4.16 mm) and 3.03 ± 0.47 mm (range 2.18 to 4.10 mm), respectively. The differences were not statistically significant (P=.148 and P=.074, respectively). The mean postoperative ACD was 4.83 ± 0.46 mm (range 3.84 to 5.76 mm) in the CTR group and 4.81 ± 0.43 mm (range 3.67 to 5.65 mm) in the control group. The difference between the groups was not statistically significant (P=.329). Implantation of a CTR had no significant influence on the postoperative axial IOL position. No author has a financial or proprietary interest in any material or method mentioned.

Coloboma de cristalino

Case reportWe present a seventy-three year-old female diagnosed with lens coloboma when she was going to be operated on for cataracts. DiscussionThe incidence of congenital coloboma of the eye is estimated to be 0.5 per 10000 newborns in Spain, 1.4 in France, 2.6 in United States, and 7.5 in China. The diagnosis is clinical by observing the defect. The visual prognosis depends on the extent and severity of the coloboma. The treatment of the cataract was by phacoemulsification with an intraocular lens using a capsular tension ring.

Safety study of capsular tension ring use in canine phacoemulsification and IOL implantation.

To evaluate and compare surgical outcome and complications in canine eyes with stable, cataractous lenses undergoing routine phacoemulsification and intraocular lens (IOL) implantation with or without implantation of a capsular tension ring device (CTR). Dogs undergoing routine bilateral phacoemulsification and IOL implantation had one eye randomly chosen to have a CTR (47 eyes) inserted while the contralateral eye served as a control (47 eyes). The CTR was placed in the capsular bag following phacoemulsification and immediately prior to IOL implantation. All eyes received acrylic foldable IOLs. Patients were evaluated intra- and postoperatively, and complications were compared between eyes with and without a CTR. There were no intra-operative complications associated with implantation of the CTR. Postoperatively, the overall incidences of glaucoma (6%), intraocular hemorrhage (4%), and retinal detachment (2%) were equal between control and CTR eyes at the time of last follow-up. There was no significant difference in overall incidence of immediate postoperative uveitis (35% vs. 38%) or fibrin (19% vs. 15%) between control and CTR eyes. Follow-up time ranged from 2 weeks to 21 months. In canine eyes with stable cataractous lenses undergoing routine phacoemulsification and IOL implantation placement of a CTR does not increase the risk of intra- or postoperative complications.

Phacoemulsification in the treatment of cataract with lens subluxation

Objective To investigate the surgical technique of phacoemulsification in the treatment of patients with cataract and lens subluxation.Methods A retrospective case series rearch.The records of 16 eyes of 16 patients who underwent surgery for cataract and lens subluxation were reviewed.Combination low energy phacoemulsification and posterior chamber intraocular lens implantation was applied in the patients with or without capsular tension ring implantation.The mean follow-up was (4.0 ± 2.3) months.The visual acuity,intraocular pressure (IOP),intraocular lens position and complication were observed.Results The postoperative visual acuities and best corrected visual acuities were improved in various degrees.The postoperative mean intraocular pressure (13.49 ± 2.32 mmHg) was significantly lower than the preoperative one (15.26 ± 3.44 mmHg) (P ＜ 0.05).The position of intraocular lens of all cases was in the center.No serious complication,such as intraocular lens dislocation,high IOP or vitreous prolapse was seen.Conclusion The low energy phacoemulsification and posterior chamber intraocular lens implantation is safety and effective in the treatment of cataract combined with lens subluxation,with slight anterior chamber reaction and few complications. Key words: Cataract ; Subluxation, lens ; Phacoemulsification ; Energy, low

Scleral-Fixated Capsular Tension Rings and Segments for Ectopia Lentis in Children

To report the short-term outcomes and complications of implantation of scleral-fixated capsular tension rings and/or capsular tension segments with intraocular lenses (IOL) in pediatric patients with ectopia lentis. Retrospective, observational case series. Thirteen consecutive pediatric patients (19 eyes) underwent placement of in-the-bag IOL with either a Cionni modified capsular tension ring or a capsular tension segment in conjunction with a conventional capsular tension ring between January 1, 2009 and March 30, 2013 by 3 anterior segment surgeons at a single academic center. The scleral fixation suture was 9-0 polypropylene in 16 eyes and CV-8 Gore-Tex (expanded polytetrafluoroethylene) in 3 eyes. Outcome measures included change in corrected distance visual acuity (CDVA) and complications. The mean age was 10.2 years ± 4.8 (SD) and the median follow-up, 23.4 months. A Cionni modified capsular tension ring was implanted in 5 eyes and a capsular tension segment with an unsutured capsular tension ring was implanted in 12 eyes. In 2 eyes, capsular tension segment alone was placed. The mean CDVA at the final follow-up (0.10 ± 0.11 logMAR, 18 eyes) was significantly better than preoperatively (0.58 ± 0.26 logMAR, 15 eyes) (P < .001). The CDVA at the final follow-up was 20/40 or better in 18 eyes (94.7%). All IOLs were well centered. Posterior capsule opacification developed in 11 eyes (57.9%), 9 eyes (47.4%) required neodymium-yttrium-aluminum-garnet capsulotomy, and 3 eyes (15.8%) required pars plana vitrectomy and posterior capsulotomy. Other complications included broken suture (5.3%) (9-0 polypropylene at CTR eyelet, repaired with CV-8 Gore-Tex), conjunctival dehiscence (5.3%), suture exposure (5.3%) (trans-scleral 9-0 polypropylene), and vitreous strand at inferior paracentesis (5.3%). Implantation of in-the-bag IOL with either a Cionni modified capsular tension ring or a capsular tension segment in conjunction with a conventional capsular tension ring appears to be a safe and effective technique for visual rehabilitation in pediatric ectopia lentis.

Fishtail on a line technique for capsular tension ring insertion

We describe a capsular tension ring (CTR) insertion technique that is a modification of the previously described fishtail technique. A suture line is used to pull the leading eyelet out through the main incision to form the fish configuration. Similar to the fishtail technique, this insertion technique minimizes the risk for zonular damage or a capsule tear because the CTR is not dialed into the capsular bag. The advantage of the suture line is that it prevents over bending of the CTR during insertion through the main incision, which can occur using the traditional fishtail technique. Neither author has a financial or proprietary interest in any material or method mentioned.

Surgical outcomes of isolated lens coloboma with or without cataract among young adults

ObjectiveTo evaluate the visual and refractive outcomes after phacoemulsification surgery in eyes with isolated lens coloboma. DesignProspective, consecutive case series. ParticipantsEighteen eyes with isolated lens coloboma of 13 patients were included in the study. Mean patient age was 13.9 ± 6.5 years. MethodsPatients underwent phacoemulsification surgery, with combined implantation of capsular tension ring (CTR) and intraocular lens. In colobomas of less than 120°, a CTR was used, whereas in colobomas of more than 120°, a Cionni-modified single eyelet CTR was used to achieve better capsular centration. The main outcome measures were uncorrected distance visual acuity, corrected distance visual acuity, refraction, and keratometry. ResultsMean logMAR uncorrected distance visual acuity and corrected distance visual acuity improved significantly from 1.53 ± 0.35 and 1.02 ± 0.47 before surgery to 0.67 ± 0.51 and 0.52 ± 0.49 at the last visit of the follow-up (p < 0.001). Mean refractive cylinder and spherical equivalent decreased significantly from –6.73 ± 1.73 and –6.72 ± 4.07 D preoperatively to –1.40 ± 1.39 and –0.83 ± 1.31 D at the end of the follow-up (p = 0.001 and p = 0.01, respectively). Mean keratometric astigmatism at preoperative and postoperative visits were 1.58 ± 0.97 and 1.65 ± 0.94 D, respectively (p = 0.70). ConclusionsPhacoemulsification with CTR and intraocular lens implantation is an effective and safe option for providing a refractive correction and a significant visual improvement in eyes with isolated lens coloboma.

Two-Step Technique for Posterior Optic Buttonholing of Intraocular Lens

This study aims to describe a two-step surgical technique for placement of a posterior chamber intraocular lens (IOL) in cases with crystalline lens subluxation resulting from non-progressive zonular dialysis. The first stage entails a phacoemulsification with creation of a 4-mm posterior capsular opening using an automated vitrector. The second stage performed 6 weeks later includes an anterior vitrectomy and injection of a foldable three-piece IOL in the sulcus. The haptics of IOL are positioned in the sulcus while the optic is pushed behind the posterior capsular opening therefore "buttonholing" the IOL. Seven eyes of seven patients with posttraumatic zonular dialysis were operated using this technique. Follow-up of all cases revealed a well-centered IOL with good postoperative visual acuity (20/20 to 20/80). Our two-stage surgical technique precludes the insertion of capsular tension ring in cases with non-progressive zonular dialysis. The technique is recommended in the presence of less than or equal to 6 clock hours of zonular dialysis with preexisting posterior capsular tear or herniation of vitreous in the anterior chamber.

Strengthening the 100‐year‐old reinforced concrete dome of the Centennial Hall in Wrocław

AbstractThe Centennial Hall, a reinforced concrete structure with an auditorium for 10000 people, was opened in Wrocław, Poland (then Breslau, Germany), in 1913 after two years of construction. Its dome, covering the whole building, has a diameter of 65.0 m and in the year it was completed was the largest reinforced concrete dome in the world. This broke the previous record, held by the dome of the Pantheon in Rome (43.3 m), which had lasted for 1787 years. This paper describes the structure of the building, its condition after 100 years of use and the renovation works carried out in 2009–2011. An important part of the renovation was strengthening the lower (tension) ring of the ribbed dome by way of external prestressing. Details concerning the assessment of the technical condition of the hall, numerical calculations and the proposed system of strengthening are presented. In 2006 the monumental Centennial Hall was listed as a UNESCO World Heritage Site for its pioneering reinforced concrete structure, designed in the style of modernism.

Three-Dimensional Limit Analysis of the Vicoforte Elliptical Dome

Limit analysis provides a conceptually simple and robust method to estimate the safety of structures and has been long applied to the analysis of the ultimate collapse state of two-dimensional masonry structures or structural elements. In revolving symmetric domes, the three-dimensional problem can be reduced to the two-dimensional case under appropriate hypotheses. The Vicoforte dome is the largest elliptical dome in the world, and its complex geometry makes this kind of analysis not straightforward. Starting from some basic assumptions, a method for analyzing the three-dimensional elliptical geometry and understand the behavior at collapse of the drum-dome system using limit analysis is proposed. The three-dimensional collapse mechanism is found and the system behavior including the presence of tension rings at different levels is interpreted. The results are compared against a nonlinear finite element model.

Using continuous intraoperative optical coherence tomography measurements of the aphakic eye for intraocular lens power calculation

Background/aimsTo include intraoperative measurements of the anterior lens capsule of the aphakic eye into the intraocular lens power calculation (IPC) process and to compare the refractive outcome with conventional IPC...

Expansion of Madrid Stadium: Foundation and Grandstands

Madrid Stadium, completed and assigned to athletics in 1992, consists of a single grandstand of large seating capacity. In 2004, the City Council of Madrid undertook the development of an expansion project for this site to convert this into a football stadium with a capacity for 70 000 spectators. The design of the stadium also took into account the possibility of transforming the structure and facilities of the building for use as an athletics stadium should the city of Madrid host Olympic Games in the future.The foundation is made up of castin-place executed piles, with up to 1500 mm diameter and 40 m length. Integrity tests were done. Micropiles were necessary to reinforce the current stadium’s foundation to bear the loads arising from the new structure.The structure of the new stadium is mainly composed of radially placed rigid frame structures that together with the existing grandstand resulted in a completely closed stadium. Precast concrete steppings are placed over these rigid frame structures. Beneath these elements there are reinforced-concrete or post-tensioned slabs that define the building’s floors. The entire structure is surrounded by perimeter walls that constitute the building enclosure.Finally, the stadium is covered with a roof structure executed with a heavy lifting system, consisting of pairs of radial pre-stressed cables connecting the outer compression ring with the inner tension ring and covering the stands with pre-stressed textile membranes.

Nd: YAG laser posterior capsulotomy rates in myopic eyes after implantation of capsular tension ring.

BackgroundThe aim f this study was to evaluate the effect of capsular tension ring implantation during cataract surgery on the incidence of neodymium: YAG (Nd: YAG) laser posterior capsulotomy in myopic (axial length [AL] ≥25.00 mm) eyes.Material/MethodsIn this retrospective study, the records of the cases of 117 myopic patients who underwent cataract surgery between January 2004 and January 2011 were reviewed. A total of 153 eyes with an axial length of 25 mm or higher were included in the study with consideration of exclusion criteria mentioned below. Eyes were grouped by presence or lack of capsular tension ring (CTR+ and CTR−, respectively).ResultsThe study included 153 eyes from 107 myopic patients. Hydrophilic acrylic IOL and capsular tension ring (CTR) were implanted in 78 eyes (CTR+ group), and 75 eyes received only the hydrophilic acrylic IOL (CTR− group). Six eyes (7.6%) in CTR+ and 16 eyes (21.3%) in CTR− required Nd: YAG laser capsulotomy within 7 years. The difference between the 2 groups was statistically significant (p=0.021).ConclusionsBecause CTRs significantly decrease subsequent need for Nd: YAG laser posterior capsulotomy in myopic patients, are very inexpensive, and provide other benefits, our data suggest that the use of CTRs in myopic eyes undergoing cataract surgery with an hydrophilic acrylic IOL implantation is advantageous and should be standard practice.

A study of complications during cataract surgery in patients with pseudoexfoliation syndrome

Aim: Pseudoexfoliation (PXE) is a common and clinically important systemic condition that affects elderly people, who are also likely to undergo cataract surgery. It can cause serious complications during cataract surgery due to the pupillary rigidity and zonular weakness and instability. The purpose of this study was to study the frequency and types of complications of small incision cataract surgery (SICS) and phacoemulsification surgery in patients with cataract and PXE. Materials and Methods: This cross-sectional descriptive study was carried out on 52 eyes of 52 patients with cataract and PXE who underwent SICS or phacoemulsification surgery in a tertiary care hospital. Their perioperative and post-operative complications were documented and analyzed through statistical package for social sciences version 15.0 (IBM). Results: Poor pupillary dilatation in spite of use of standard mydriatic drops and non-steroidal anti-inflammatory drugs was the most common finding. This single factor made subsequent steps of surgery very difficult due to poor peripheral visualization. Pupillotomy was done in 25% cases. Other problems encountered were accidental iridodialysis, posterior capsule rupture, vitreous loss, retained cortical matter, decentered intraocular lens and zonular dialysis. Conclusion: Presence of associated PXE in cataract patients significantly increases the risk of vision threatening complications. Use of flexible iris hooks for small pupils and for capsular stability, capsular tension rings and high viscosity viscoelastics are useful modifications of surgical technique for good visual outcome.

Optimizing outcomes of multifocal intraocular lenses

To update the readers on recent research for further optimizing outcomes and improving the patient satisfaction with multifocal intraocular lenses (IOLs). Recent studies provide few novel approaches on surgical interventions to improve the postoperative outcomes. The use of capsular tension rings can improve preoperative predictability, whereas femtosecond laser cataract surgery was not shown to provide significant benefit to postoperative visual acuity. Other studies broaden and reinforce the previously reported results, such as patient education with blurred vision and dysphotopsia, utilizing an add power of +3.00 to improve intermediate visual acuity, and minimizing the lens decentration and tilt. Multifocal IOLs are currently a popular lens choice for motivated patients who would like to achieve spectacle independence. However, recent research has not provided significant improvements in optimizing outcomes. Newer lens technologies may be required to resolve the current problems of blurred vision and dysphotopsias.

Surgical management of spontaneous in-the-bag intraocular lens and capsular tension ring complex dislocation

We describe a technique to manage late spontaneous intraocular lens (IOL) and capsular tension ring (CTR) dislocation within the intact capsular bag. The subluxated IOL and CTR complex can be positioned in a closed chamber and fixed to the pars plana at both 3 and 9 o’clock quadrants with the presented ab externo direct scleral suturation technique which provides an easy, safe and effective surgical option for such cases.

Treatment of Congenital Aniridia Associated with Subluxated Infantile Cataract

A 5 year old boy was presented at Eye clinic University clinical center Tuzla with congenital aniridia in both eyes. Clinical examination revealed visual acuity of 0,08 without correction in right and 0.7 with -5.0 Dsph and -1.0 Dcyl Axx 109° in left eye. Opthalmologic examination showed bilateral aniridia associated with moderate cataract in the right and incipient cataract in the left eye. In the right eye, zonular weakness with incipient capsular displacement and esotropia of Δ6º, were noted. The patient underwent phacoemulsification, implantation of capsular tension ring and Artificial Iris implant in the capsular bag. Phacoemulsification went uneventful and early postoperative recovery was successful with no signs of aniridia-associated keratopathy development and normal values of intra ocular pressure. Patient was not motivated for operation of the left eye and it was corrected with soft contact lens. Six month after the operation visual acuity in the right eye improved to 0.9 with +1.25Dsph and maintained stable in left eye, with complete elimination of esotropia and signs of binocular vision restoration. Small incision cataract extraction with IOL and Artificial Iris implantation in one procedure can be used to correct congenital aniridia and cataract with significant visual function improvement.

Influence of capsular tension ring on posterior capsule opacification in myopic eyes

Purpose:To determine the effect of a capsular tension ring (CTR) implantation in preventing posterior capsular opacification (PCO) after cataract surgery in patients with high myopia.Materials and Methods:In this prospective single-surgeon standardized-surgical-procedure fellow-eye comparison trial, 34 patients with high myopia had phacoemulsification surgery. Although one eye received an acrylic intraocular lens (IOL) and CTR, other eye received only an IOL as control. PCO, within the capsulorhexis overlap, was documented by standardized digital retroillumination images at least 2 years post-operatively, and the percentage area of PCO was scored (scale 0%-100%) using the POCOman software system. The PCO score and the incidence of neodymium-doped yttrium aluminum garnet (Nd: YAG) capsulotomy of groups, and correlations between PCO score and presence of CTR, age, phaco time, refraction, and axial length (AL) were determined.Results:The mean time interval from surgery to PCO measurement was 43.4 ± 11.2 months for the eyes with a CTR and 43.1 ± 11.6 months for the controls (P = 0.91). The PCO score of the eyes with a CTR was significantly lower than in the controls (5.9 ± 4.3 vs. 22.3 ± 12.2, respectively; P < 0.001). There were statistically insignificant correlations between PCO score and pre-operative refraction (r = 0.02; P = 0.90), AL (r = 0.03; P = 0.80), phaco time (r = 0.11; P = 0.53), and patient's age (r = 0.23; P = 0.55). No patient with a CTR had a Nd: YAG laser capsulotomy, but it was six in controls (P = 0.025).Conclusions:CTR implantation seems to be effective in reducing the PCO and Nd: YAG laser capsulotomy rates in high myopic eyes.

Technology of phacoemulsification in extensive zonular defects of zinn ligament fibers

Aim. To describe the technique and to assess the results of phacoemulsification in eyes with extensive zonular defects of Zinn ligament fibers. Methods. Phacoemulsification was performed through a 2.2- mm corneal tunnel incision on adhesive viscoelastic bed. The lens was stabilized with a capsular tension ring. The operation was finished with intraocular implantation and its suturing to the iris. The study included 36 patients [42 eyes, 23 males (63.9%), 13 females (36.1%)] in whom phacoemulsification has been performed. Visual acuity before surgery ranged from 0.01 to 0.7 (mean 0.2±0.18). Intraocular pressure ranged from 15 to 25 mm Hg (mean 19.2±4.5 mm Hg). Corneal astigmatism value before surgery ranged from 0 to 2.25 D (mean 0.87±0.63 D). Results. Postoperatively the following complications were observed: an inflammatory reaction in 3 eyes (7.1%), inflammation of Descemet’s membrane in 3 (7.1%) cases, ocular hypertension in 9 (21.4%) eyes. All the complications were drug treated within 3-5 days. On the second day mean visual acuity was assessed as 0.56±0.12,1 month after surgery - 0.70±0.16,6 months after surgery - 0.75±0.21, and 1 year after surgery - 0.74±0.19. Corneal induced astigmatism 1 year after the surgery ranged from 0.0 to 1.5 D (mean 0.39±0.16 D). Conclusion. The presented technology of phacoemulsification is relatively safe, effective and provides a possibility to rehabilitate patients with cataract combined with extensive zonular defects of Zinn ligament fibers in minimal terms.

Series of fibrinous inflammation after implantation of capsular tension rings

To analyze the cause of fibrinous inflammation in eyes with capsular tension rings (CTRs) after cataract surgery. Department of Ophthalmology, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany. Retrospective case series. High-performance liquid chromatography was implemented to eliminate impurities. One CTR was explanted for microbiologic examination. The pH values of the CTR and the storage solution were analyzed, Seldi and Maldi tests were performed, as well as toxicity tests with immortal cell lines. Material batches were analyzed. The organic carbon content of CTRs, detergents, and storage solutions was checked. The presence of endotoxins was excluded with the limulus amoebocyte lysate test. Gas chromatography with mass selective detector excluded the presence of extractable organic substances. An inductively coupled plasma analysis scanned for inorganic substances. The microbial count in operating rooms, smear tests, and microbiologic examinations of technical devices were initiated. Analyses found no pathological findings. After intensive systemic and topical treatment with antibiotics and steroids, clinical findings improved. The implantation of CTRs was stopped immediately. No further cases occurred. Fibrinous inflammations after implantation of CTRs were unknown until now. Contamination and/or irritation by detergents or the material CTR itself were excluded, indicating mechanical or toxic irritation by the CTR. No author has a financial or proprietary interest in any material or method mentioned.