Zonular Weakness Research Articles

Outcome of phacoemulsification and intraocular lens implantion in eyes with pseudoexfoliation and weak zonules.

To evaluate the results of phacoemulsification and intraocular lens (IOL) implantation in eyes with pseudoexfoliation (PEX) and zonular weakness. Two hundred and ninety-five patients (295 eyes) were recruited. This study is a retrospective case review of 143 PEX eyes with preoperative (Group 1) and intraoperative (Group 2) signs of zonular weakness, 76 PEX eyes (Group 3) and 76 non-PEX eyes without zonular weakness (Group 4) undergoing phacoemulsification and IOL implantation performed by single surgeon from year 1988 to 2010. Outcome measures included frequency of postoperative pseudophakodonesis, anterior capsule contraction and IOL decentration/dislocation. Postoperative vision, intraocular pressure (IOP) and glaucoma medication requirements were also assessed. A subanalysis on identical postoperative outcomes of capsular tension ring (CTR) implantation was performed. Comparisons were made for 52 PEX eyes with zonular weakness receiving nonsutured CTR implantation (Group A), 91 PEX eyes with zonular weakness not receiving CTR implantation (Group B) and 142 PEX eyes without zonular weakness (Group C). Mean follow-up was 4.08±0.48years and maximum was 8.3years. Both Groups 1 and 2 showed higher incidence of complications than Groups 3 and 4 (p < 0.01). Vision, IOP and glaucoma medication requirements were similar postoperatively for all four groups. Groups A and B had a significantly higher proportion of postoperative complications than Group C (p<0.01). There was no significant difference in risk of developing these complications between Groups A and B (p=0.64). Postoperative complication rates are higher in PEX eyes with preoperative and/or intraoperative signs of zonular weakness undergoing phacoemulsification. Nonsutured CTR implantation does not prevent IOL and capsular complications postoperatively.

Intraoperative intracameral pilocarpine after capsular tension ring and capsule/iris hook insertion in pediatric eyes with subluxated cataract

Capsular tension rings and iris hooks have proved to be useful devices in cataract surgery in cases of zonular weakness and dialysis. We describe the use of intracameral pilocarpine-induced pupillary miosis to couple the iris and the capsulorhexis edge with iris hooks during phacoemulsification in pediatric cases with posttraumatic subluxated cataractous lens. The coupled iris and capsule act as a single unit, eliminating the space between them and significantly reducing the possibility of vitreous or ophthalmic viscosurgical device passing through the zonular defect. No author has a financial or proprietary interest in any material or method mentioned.

Analysis of Intraoperative and Postoperative Complications in Pseudoexfoliation Eyes Undergoing Cataract Surgery

Pseudoexfoliation (PXE) is a genetically inherited condition affecting usually seen in those aged over 50 years. Surgical management of cataract in patients with PXE pose a challenge due to associated changes in ocular structures. To study the challenges in the management of cataract in patients with PXE. This was an interventional study conducted in the Ophthalmology Department of MS Ramaiah Medical College and Memorial Hospital, Bangalore from June 2012 to September 2014. All patients admitted for cataract surgery during this period who were diagnosed as cataract associated with PXE above 50 years of age belonging to either sex were included in the study. All patients underwent cataract surgery with intraocular lens implantation. Depending on type of cataract both small incision and phacoemulsification operations were conducted. Intraoperative and postoperative complications were studied. The patients were reviewed up to 6 weeks postoperatively. A total of 50 eyes of 50 patients diagnosed as cataract with PXE underwent cataract surgery. Of which 40 eyes (80%) underwent small incision cataract surgery whereas, 10 (20%) underwent phacoemusification. Corneal thinning (<535 microns) was noted in majority of the cases (41 cases). Preoperatively there were 3 cases of zonular weakness. Pseudo exfoliation with glaucoma was seen in 5 cases. Intraoperative complications encountered during surgery were; zonular dialysis in 3 cases, posterior capsular tear in 2 cases, out of these 5 cases vitreous loss was seen in 3 cases. Postoperative complications were corneal odema in 17 cases, of which endothelium de-compensated in one case, while early posterior capsular opacification was seen in 6 cases. Final best corrected visual acuity was between 6/6-6/12 in 39(78%) eyes, 6/18 -6/36 in 6(12%) cases; 6/60 to less in 5(10%) cases. Cataract surgery in eyes with PXE has higher incidence of intraoperative and postoperative complications. A complete preoperative workup helps reduce intraoperative complications and maximises the postoperative results. As corneal thinning is more common a pre-operative pachymetry is desirable to prevent underdiagnoses of glaucoma.

Objective Evaluation of Zonular Weakness: Measurement of Lens Movement at the Start of Capsulorhexis Using Extracted Porcine Eyes

Objective: To evaluate the degree of zonular weakness based on lens movement at the start of capsulorhexis using extracted porcine eyes. Methods: Zonular dehiscence of 18°, 36°, and 54° was created and alternated with healthy areas into five zones to create a model simulation of weakness of the zonule of Zinn corresponding to dehiscence of 90°, 180°, and 270°. During continuous curvilinear capsulorhexis (CCC), an image displaying the anterior capsule grasped by a cystotome and another displaying the initial tear were captured, and the two images were superimposed to measure the movement distance of the cortical opacities created using a hook. Porcine eyes with no dehiscence were used as the control group. Results: Compared with a distance of 0.44 ± 0.13 mm in the control group, the cortical opacity movement distances in the weakness group with dehiscence corresponding to 90°, 180°, and 270° were 0.68 ± 0.27, 1.01 ± 0.22, and 1.32 ± 0.35 mm, respectively. Significant differences were observed between the control, 90°, 180°, and 270° dehiscence groups (P<0.001). Conclusion: This study revealed numerical data for the degree of weakness of the zonule of Zinn in porcine eyes. Clinical application of this method may be useful for establishing surgical procedures and prognoses for cataract surgery in patients with weakness of the zonule of Zinn.

Indications and clinical outcomes of capsular tension ring implantation in phacoemulsification surgery at a tertiary teaching hospital: A review of 4316 cataract surgeries

To reveal the indications, clinical outcomes and complications of capsular tension ring (CTR) implantation in a series of consecutive phacoemulsification surgeries during a three-year interval. A review of all patients undergoing cataract surgery with insertion of a CTR between 2010 and 2013 was conducted at our tertiary teaching ophthalmology department. The demographic details of patients, indications and clinical outcomes of CTR implantation were evaluated. Between 2010 and 2013, 4316 phacoemulsification surgeries were performed and of these surgeries CTR implantation was done in 41 eyes of 36 patients. The indications of CTR implantation were zonular dehiscence or weakness associated with mature cataract (29.2%), trauma (24.3%), pseudoexfoliation syndrome (19.5%), retinitis pigmentosa (14.6%), degenerative myopia (9.7%), and lens coloboma (2.4%). Posterior chamber intraocular lens (PCIOL) was implanted into the capsular bag in all eyes. Dislocation of PCIOL was not observed in any case. Transient IOP increased in 5 eyes (12%) and corneal edema in 14 eyes were noted. Posterior capsular opasification in 1 eye (2.4%), anterior capsule phimosis in 1 eye (2.4%) and cystoid macular edema in 1 eye (2.4%) were detected as late complications. The frequency of CTR implantation was 0.97% due to our study. In complicated cataract surgeries, CTR implantation seems to improve clinical outcomes.

Pseudoexfoliation - A Dreaded Nightmare in Cataract Surgery

Aim : Pseudoexfoliation (PXE) is a common and clinically important systemic condition in elderly people that affects the outcome of cataract surgery. It can cause various complications during cataract surgery due to pupillary rigidity and zonular weakness and instability. The purpose of this study was to evaluate the frequency and types of complications of Phacoemulsification in patients with cataract and PXE. Materials and Methods: This cross sectional, prospective study was carried out on 60 eyes of 60 patients with cataract and PXE who underwent phacoemulsification in a tertiary care hospital. Their perioperative and post-operative complications were documented and analyzed. Results: Poor pupillary dilatation in spite of use of standard mydriatic drops and NSAID was the most common perioperative finding. This single factor made subsequent steps of surgery more difficult due to poor visualisation. Conclusion: Presence of associated PXE in cataract patients significantly increases the risk of vision threatening complications. Use of flexible iris hooks for small pupils, capsular tension rings for capsular stability and high viscosity viscoelastics are useful adjunct during surgical technique for good visual outcome.

Результаты факоэмульсификации катаракты с различной плотностью ядра в зависимости от состояния цинновых связок

Результаты факоэмульсификации катаракты с различной плотностью ядра в зависимости от состояния цинновых связок

Results of phacoemulsification of cataract complicated by lens subluxation depending on the ring setting method

Actuality. Cataract extraction complicated by zonular weakness remains one of the urgent problems of eye microsurgery. Aim. To increase the efficiency of cataract surgery complicated by lens subluxation through comparative analysis of frequency and structure of intra- and postoperative complications, as well as the functional results of surgical treatment of patients depending on the ring setting method. Methods and results. 91 patients (93 eyes) were examined, who were operated on complicated cataract, and were divided into 2 groups depending on the method of ring setting. Conclusion. It was established that the offered method of implant capsular ring gives the opportunity to reduce the length of patients’ treatment by 2,6 day, to decrease of 28,43% for complications, and also to avoid such heavy operating complications, as a vitreous prolapse, displacement of the eye lens fragments in a vitreous body, dug up capsule bag.

Outcome of Capsular Tension Ring (CTR) Implant in Complicated Cataracts.

Surgery in the presence of zonular weakness or subluxated lens was a great surgical challenge and included intracapsular cataract extraction with anterior chamber IOL implantation or pars plana lensectomy and vitrectomy with a sutured (IOL). Modern surgical approache involves placement of endocapsular flexible PMMA ring that prevents iatrogenic loss of zonular support, minimizing vitreous loss and enables placement of in the bag IOL. To evaluate frequency and indications of capsular tension ring (CTR) implant and analyse the visual and anatomical outcome in various complicated cataract surgeries. Retrospective screening of database of 6000 consecutive cataract surgeries was done. BCVA, complete ocular examination with SLEx, intraocular pressure, direct ophthalmoscope, fundus examination with +78/+90D were noted. CTR was implanted in cases where Zonular dialysis of > 3 clock hours was present or capsular bag instability was detected during capsulorhexis or subsequent intraoperative maneuvers. In cases with capsulorrhexis extension, CTR was not implanted. Records were analysed for indication of CTR implant and clinical outcome on Day 1, 1 month and 6 month follow up. In this series CTR implant was done in 45 cases. The indications were hypermature senile cataract in 9 cases, hypermature senile cataract with lens induced glaucoma in 9 cases, pseudoexfoliation syndrome in 9 cases, post blunt injury traumatic cataract in 6 cases, iridochoroidal coloboma in 6 cases, hypermature cataract with pseudoexfoliation and marfan syndrome in 3 cases respectively. Decision of CTR implant was intraoperative in 42 patients. At 6 month follow up, 39 patients had best corrected visual acuity ≥6/12. IOL decentration was detected in only 3 cases, but without any subjective visual complaints. As per the results CTR was used very infrequently (0.75%) but remains useful in cataract surgeries with difficult pre and intraoperative conditions. It gives good postoperative result and creates satisfied patients.

Epidemiology, Etiology, and Prevention of Late IOL-Capsular Bag Complex Dislocation: Review of the Literature

Posterior chamber intraocular lens (PC-IOL) subluxation is uncommon but represents one of the most serious complications following phacoemulsification. Late spontaneous IOL-capsular bag complex dislocation is defined as occurring three months or later following cataract surgery. Unlike early IOL dislocation, late spontaneous IOL dislocation is due to a progressive zonular dehiscence and contraction of the capsular bag many years what seemed to be uneventful surgery. In recent years, late in-the-bag IOL subluxation or dislocation has been reported with increasing frequency, having a cumulative risk of IOL dislocation following cataract extraction of 0.1% after 10 years and 1.7% after 25 years. A predisposition to zonular insufficiency and capsular contraction is identified in 90% of reviewed cases. Multiple conditions likely play a role in contributing to this zonular weakness and capsular contraction. Pseudoexfoliation is the most common risk factor, accounting for more than 50% of cases. Other associated conditions predisposing to zonular dehiscence are aging, high myopia, uveitis, trauma, previous vitreoretinal surgery, retinitis pigmentosa, diabetes mellitus, atopic dermatitis, previous acute angle-closure glaucoma attack, and connective tissue disorders. The recognition of these predisposing factors suggests a modified approach in cases at risk. We review certain measures to prevent IOL-bag complex luxation that have been proposed.

Rapid anterior capsular phimosis after cataract surgery in a patient with chronic angle closure glaucoma

We report a case of complete occlusion of capsulorrhexis opening in a patient with chronic angle closure glaucoma with fixed–dilated pupil in the following 2 weeks after an uneventful cataract surgery. The capsulorrhexis diameter was intended to make between 5.0 mm and 5.5 mm, to prevent photophobia afterward. There was no evidence of zonular weakness on preoperative examination or during the surgery. Nd:YAG anterior capsulotomy was performed for capsular phimosis and to enlarge capsulorrhexis. The patient regained her visual acuity 3 days after laser treatment, and no pseudophakodonesis, intraocular lens decentration, and re-phimosis were noted at the 3-month follow-up.

English

Pseudoexfoliation (PEX) syndrome is an age-related systemic disorder with major ocular manifestations. It is characterized by the production and deposition of fibrillogranular amyloid-like extracellular material within many ocular tissues. Pseudoexfoliation is also a risk factor for glaucoma and also correlated to an increased incidence of cataract formation. Cataract surgery in eyes with pseudoexfoliation is connected with many complications and presents challenges that require careful preoperative planning and intraoperative care to ensure safe surgery and successful postoperative outcome. Zonular weakness and poor pupillary dilation are the two major risk factors for surgical complications and poor visual acuity after surgery. With proper preparation and the use of specialized adjunctive devices, phacoemulsification is the preferred procedure of cataract extraction in this group of patients. Postoperatively, patients require frequent and detailed follow-up to monitor for complications such as intraocular pressure rise, inflammation and intraocular lens dislocation. In conclusion, with appropriate preoperative, intraoperative and postoperative care, the risk of complications can be minimized and favorable outcomes may be achieved in cataract surgery in eyes with pseudoexfoliation syndrome.

Clinical outcomes of sleeveless phacotip assisted levitation of dropped nucleus

Background/aimTo demonstrate the feasibility of a sleeveless phacotip-assisted approach to levitate dropped nucleus.MethodsThis single-centre, retrospective, interventional, non-comparative case series reviewed the medical records of 34 eyes of 34 patients. Corrected...

Effect of an aspheric intraocular lens on the ocular wave‐front adjusted for pupil size and capsulorhexis size

To compare the ocular wave-front of eyes with silicone Intraocular lens (IOLs) with aspheric and spherical optics after cataract surgery, taking into account the patient's pupil size under reading conditions and after pupil dilatation. In this institutional prospective, randomized, controlled, patient and examiner masked, bilateral trial with intra-individual comparison, 60 eyes of 30 patients with bilateral age-related cataract were included. Each patient received a spherical IOL (CeeOn Edge, 911A, AMO, Santa Ana, CA, USA) in one eye and an aspheric IOL (Tecnis, Z9000, AMO) in the contra-lateral eye. Exclusion criteria were other ocular pathologies, capsular changes or zonular weakness. The main outcome variable was spherical aberration of the ocular wave-front under mesopic pupil conditions measured 2 years after surgery. Additional outcome variables were visual acuity and photopic and mesopic contrast sensitivity. There was no significant difference in visual acuity between the two IOL types under physiological pupil conditions and also not after pupil dilation. However, spherical aberrations were significantly lower with the aspheric IOL (SA: spherical 0.38 μm, SD: 0.11 μm; aspheric 0.10 μm, SD: 0.13 μm; p < 0.01), and there was a significant difference in contrast sensitivity at 12 cycles/degree. This is the first randomized and masked trial on visual function and ocular wave-front after implantation with this silicone aspheric IOL, taking the patients' own pupil size into account. The effect on visual function was detectable for mesopic contrast sensitivity, but there was no difference in visual acuity. The SA was found to be significantly lower under physiological pupil conditions as well as when recalculated for the rhexis size and under pharmacological dilatation.

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.

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.

Intraocular lens optic capture in eyes with zonular weakness in cataract patients

We desribe a technique for managing cataracts in eyes with zonular weakness. The technique is a combination of microhook iris retractors to fixate the capsulorhexis, a capsular tension ring, and intraocular lens optic capture. Results of this technique in 70 eyes after a 13-month mean follow-up are reported.

Exfoliation syndrome

Exfoliation syndrome is the most common identifiable cause of glaucoma in the world. It has been associated with many ocular problems, such as secondary open angle glaucoma, corneal dysfunction, cataract, and zonular weakness, and may have systemic manifestations as well. This review focuses on recent genetic and pathophysiologic discoveries in the disease process. Exfoliation syndrome is a progressive age-related condition of the extracellular matrix (ECM), which has various ocular implications, most notably open angle glaucoma, zonular abnormalities, and cataract formation. The pathophysiology behind exfoliation syndrome appears to involve both genetic and environmental components. The underlying genetic mechanisms are thought to be due to disruption of regulatory genes (lysyl oxidase-like and clusterin) that are involved in both the production and the breakdown of ECM material. Disease manifestations involve the accumulation and deposition of ECM fibrils throughout the eye thought to be engendered by an increased oxidative stress state. A greater understanding of the genetic and pathophysiologic mechanisms underlying the disease may lead to the development of new approaches in its treatment and management.

Completion rates of anterior and posterior continuous curvilinear capsulorrhexis in pediatric cataract surgery for surgery performed by trainee surgeons with the use of a low-cost viscoelastic

Dear Editor, We would like to congratulate Dr. Muralidhar and his colleagues for the study on a subject which is an established clinical practice at least in developing countries, but has never been well documented. Results of this study are of great value for ophthalmologists in developing countries like India where care and cost of care has to be finely balanced. In their non-randomized observational study, Muralidhar et al., found that the completion rate of anteriorcontinuouscurvilinear capsulorrhexis by trainee surgeons with the use of 2% hydroxypropylmethycellulose was 66.7% and overall completion rate with the help of a senior surgeon was 81.8%.[1] This is acceptable as compared to 90% completion rate with use of Healon in studies by Jeng et al.[2] Again, Hamada et al., reported a completion rate of anterior and posterior capsulorrhexis of 100% with use of Healon GV.[3] The completion rates of posterior capsulorrhexis reported by the authors in their study was 90%, which is fairly comparable. We feel that the authors have not factored in two variables which may change the outcomes in a similar study. These two factors are the age of the patient and the experience of the surgeon. Majority of the patients in their study group are 2 years or older except one patient. Only 1 child who is under 2 years had an extension of the anterior rhexis. Cataract surgery in younger children often is more challenging in view of higher positive vitreous pressure and shallower anterior chambers.[4] With the publication of Infant Aphakia Treatment Study results, more children younger than two years are likely to undergo primary intraocular lens (IOL) implantation.[5] We genuinely feel that this study could have been more valuable and complete had the authors included more children less than 2 years of age. We also feel that completion rates will be lower in younger children with use of low cost viscoelastics. We agree with the authors in their conclusion, that the completion rates are expected to be better for experienced surgeons. It would have been helpful if they had compared completion rates of experienced surgeon to that of trainees in age matched controls. In addition, the authors have not included cataracts with anterior segment anomalies like zonular weakness, fibrotic capsules, capsular plaques, persistent hyperplastic primary vitreous etc., in their study. Further studies are needed to assess completion rates with low cost viscoelastic in these admittedly difficult cases.

Pseudoexfoliative syndrome: Revisited

Pseudo exfoliation syndrome is the most common cause of secondary open angle glaucoma wherein due to poorly understood reasons, an unknown substance, a pseudoexfoliative material, is deposited on the anterior lens capsule and other structures of the anterior segment, especially the cornea, iris, pupillary margins, angles and zonules. Fifty percent of these patients ultimately develop glaucoma. The glaucoma when developed is more aggressive, exhibits more pressure fluctuations and is more resistant to standard lines of care and management. Therefore, these cases require close follow-ups and lifelong monitoring. Cataract surgery in these cases also requires special pre-operative planning and intraoperative management because of the attendant problems like poorly dilating pupils and zonular weakness. A major concern with this condition is that the deposition of the material continues throughout the life of the patient leading to unexpected complications at any time, which warrants intensive counseling patient. After extensive internet surfing and literature search, we herein attempt to present the important features of this common, but yet under recognized and less understood disease.