Zonular Weakness

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Alan S Crandall - One of the best experts on this subject based on the ideXlab platform.

  • new capsular tension segment with 2 point fixation for Zonular Weakness
    Journal of Cataract and Refractive Surgery, 2017
    Co-Authors: Malkit K Singh, Balamurali K Ambati, Alan S Crandall
    Abstract:

    We describe clinical applications and surgical techniques for a new type of capsular tension segment (CTS) for use during cataract surgery. The Ambati CTS is distinguished from other CTS devices by having 2 eyelets close to each other, which allows it to distribute tension to 2 points, avoiding too much stress at a single point on the anterior capsulotomy, which prevents peaking of the capsulorhexis, and potentially reducing the risk for anterior capsule tear. Two of these CTS devices could possibly be used to provide 4-point fixation of a capsular bag in eyes with near-complete Zonular instability. We describe 4 cases and 2 surgical techniques for implanting the new CTS, 1 technique in an adult patient with Zonular Weakness secondary to trauma and the other in 3 children with subluxated lenses due to Marfan syndrome.

  • spontaneous bilateral anterior partial in the bag intraocular lens dislocation following routine annual eye examination
    Journal of Cataract and Refractive Surgery, 2014
    Co-Authors: Joshua R Ford, Liliana Werner, Leah A Owen, Shail Vasavada, Alan S Crandall
    Abstract:

    We present the case of an 81-year-old man with pseudoexfoliation syndrome (PXF) in whom spontaneous bilateral anterior partial in-the-bag intraocular lens (IOL) dislocation was diagnosed following a routine dilated examination that demonstrated only mild pseudophacodonesis with no evidence of subluxation. Uneventful cataract surgery with placement of single-piece hydrophobic acrylic posterior chamber IOLs had been performed in both eyes 7 years previously. Bilateral IOL repositioning with scleral fixation was performed to correct the dislocation. Postoperative examinations showed remarkable improvement in visual acuity and IOL stability. We hypothesize that Zonular Weakness secondary to PXF predisposed the patient to bilateral IOL partial dislocation. Pupil dilation in the setting of mild pseudophacodonesis at the time of routine examination may have been a precipitating factor. To our knowledge, bilateral IOL subluxation/dislocation has been described in a limited number of case reports. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

  • spontaneous late dislocation of intraocular lens within the capsular bag in pseudoexfoliation patients
    Ophthalmology, 2001
    Co-Authors: Faisal S Jehan, Nick Mamalis, Alan S Crandall
    Abstract:

    Abstract Purpose To identify a delayed complication of cataract surgery in patients with Zonular Weakness caused by pseudoexfoliation syndrome. Design Retrospective observational case series. Participants Eight eyes in seven patients with clinically diagnosed pseudoexfoliation syndrome who had undergone previous uncomplicated cataract extraction and placement of a posterior chamber intraocular lens. Methods This study evaluated eight cases of late spontaneous dislocation of posterior chamber intraocular lenses within the capsular bag in patients with pseudoexfoliation syndrome. Data were gathered retrospectively from patients’ operative reports, medical records, and pathology reports. Main outcome measures (1) Interval between original surgery and dislocation; (2) final best-corrected visual acuity and ocular outcome. Results All patients had a diagnosis of pseudoexfoliation syndrome and had previously undergone uncomplicated cataract surgery. No patient had any other predisposing factors that would lead to Zonular dehiscence or Weakness. Delayed dislocation of the entire capsular bag containing the intraocular lens (IOL) occurred spontaneously in all cases. Mean time from IOL implantation to dislocation was approximately 85 months (7 years and 1 month; range, 57–115 months) after surgery. Seven eyes were treated successfully with IOL exchange: six with placement of an anterior chamber IOL and one with scleral fixation of a posterior chamber IOL. The remaining case was treated by scleral fixation of the dislocated IOL. Gross pathology analysis of seven cases confirmed the presence of the IOL within the intact capsular bag. Six eyes have achieved final best-corrected visual acuity of 20/40 or better. Conclusion Patients with pseudoexfoliation syndrome may be at risk for delayed spontaneous dislocation of IOL within the capsular bag after uncomplicated cataract surgery. Awareness of this newly recognized long-term complication may justify a reevaluation of surgical considerations for cataract removal in these patients.

Nick Mamalis - One of the best experts on this subject based on the ideXlab platform.

  • capsulorhexis phimosis with anterior flexing of an accommodating iol case report and histopathological analyses
    Journal of Cataract and Refractive Surgery, 2014
    Co-Authors: Rachel H Epstein, Liliana Werner, Erica T Liu, Thomas Kohnen, Oliver K Kaproth, Nick Mamalis
    Abstract:

    We describe the case of a patient who had cataract surgery with implantation of an accommodating hydrophilic acrylic intraocular lens (IOL) that exhibited capsulorhexis phimosis and in-the-bag IOL luxation leading to explantation of the IOL–capsular bag complex 10 years after implantation. Constriction of the capsular bag secondary to fibrosis caused significant anterior flexing of the haptic elements of the IOL. Histopathological analysis revealed dense anterior subcapsular fibrosis and fibrous metaplasia of the anterior lens epithelial cells. No signs suggestive of pseudoexfoliation were found. This case raises concerns related to the continuously evolving indications for implantation of accommodating and other highly flexible IOLs (eg, microincision IOLs), particularly in patients with no clear predisposition to Zonular Weakness and, accordingly, excessive capsular bag contraction. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

  • spontaneous late dislocation of intraocular lens within the capsular bag in pseudoexfoliation patients
    Ophthalmology, 2001
    Co-Authors: Faisal S Jehan, Nick Mamalis, Alan S Crandall
    Abstract:

    Abstract Purpose To identify a delayed complication of cataract surgery in patients with Zonular Weakness caused by pseudoexfoliation syndrome. Design Retrospective observational case series. Participants Eight eyes in seven patients with clinically diagnosed pseudoexfoliation syndrome who had undergone previous uncomplicated cataract extraction and placement of a posterior chamber intraocular lens. Methods This study evaluated eight cases of late spontaneous dislocation of posterior chamber intraocular lenses within the capsular bag in patients with pseudoexfoliation syndrome. Data were gathered retrospectively from patients’ operative reports, medical records, and pathology reports. Main outcome measures (1) Interval between original surgery and dislocation; (2) final best-corrected visual acuity and ocular outcome. Results All patients had a diagnosis of pseudoexfoliation syndrome and had previously undergone uncomplicated cataract surgery. No patient had any other predisposing factors that would lead to Zonular dehiscence or Weakness. Delayed dislocation of the entire capsular bag containing the intraocular lens (IOL) occurred spontaneously in all cases. Mean time from IOL implantation to dislocation was approximately 85 months (7 years and 1 month; range, 57–115 months) after surgery. Seven eyes were treated successfully with IOL exchange: six with placement of an anterior chamber IOL and one with scleral fixation of a posterior chamber IOL. The remaining case was treated by scleral fixation of the dislocated IOL. Gross pathology analysis of seven cases confirmed the presence of the IOL within the intact capsular bag. Six eyes have achieved final best-corrected visual acuity of 20/40 or better. Conclusion Patients with pseudoexfoliation syndrome may be at risk for delayed spontaneous dislocation of IOL within the capsular bag after uncomplicated cataract surgery. Awareness of this newly recognized long-term complication may justify a reevaluation of surgical considerations for cataract removal in these patients.

Saori Yaguchi - One of the best experts on this subject based on the ideXlab platform.

  • objective classification of Zonular Weakness based on lens movement at the start of capsulorhexis
    PLOS ONE, 2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Tadahiko Kozawa, Yukari Yagiyaguchi, Hiroko Bissenmiyajima
    Abstract:

    Purpose To quantify Zonular Weakness based on lens movement at the start of continuous curvilinear capsulorhexis (CCC) and establish a classification system for it. Setting Kozawa Eye Hospital and Diabetes Center, Mito, Japan. Design Retrospective interventional case series. Methods We examined 402 consecutive eyes of 316 patients who underwent CCC, phacoemulsification and aspiration (PEA), and intraocular lens (IOL) implantation. The movement of the lens capsule was measured using images from video recordings of the CCC procedure. Zonular Weakness was classified based on the shifted distance: Grade I, less than 0.20 mm; Grade II, 0.20–0.39 mm; and Grade III, greater than 0.40 mm. For each of these grades, we examined the use of the capsule stabilization device during PEA, the surgical procedure for lens removal, and IOL fixation. Results We classified 276 eyes (68.6%) as Grade I, 102 eyes (25.4%) as Grade II, and 24 eyes (6.0%) as Grade III. As the grade increased, the use of the capsule stabilization device in PEA and scleral suture fixation of IOL increased. Conclusions Zonular Weakness was quantified by measuring the movement of the lens capsule. An objective classification of Zonular Weakness based on lens movement may be useful for selecting the appropriate device and procedure during cataract surgery.

  • Classification of Zonular Weakness.
    2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Yukari Yagi-yaguchi, Tadahiko Kozawa, Hiroko Bissen-miyajima
    Abstract:

    Classification of Zonular Weakness.

  • Surgical procedure for lens removal.
    2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Yukari Yagi-yaguchi, Tadahiko Kozawa, Hiroko Bissen-miyajima
    Abstract:

    The use of a capsule stabilization device during phacoemulsification and aspiration increased as the Zonular Weakness grade (I–III) increased.

  • Surgical procedure for intraocular lens (IOL) fixation.
    2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Yukari Yagi-yaguchi, Tadahiko Kozawa, Hiroko Bissen-miyajima
    Abstract:

    The rate of scleral suture fixation of the IOL and scleral suture fixation of the capsule using a modified-capsule expander increased as the Zonular Weakness grade (I–III) increased.

  • objective evaluation of Zonular Weakness measurement of lens movement at the start of capsulorhexis using extracted porcine eyes
    Journal of Clinical & Experimental Ophthalmology, 2016
    Co-Authors: Yukari Yaguchi, Saori Yaguchi, Shigeo Yaguchi, Tadahiko Kozawa, Yuichiro Tanaka, Kazuno Negishi, Kazuo Tsubota
    Abstract:

    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.

Aliza Jap - One of the best experts on this subject based on the ideXlab platform.

  • management of severely subluxated cataracts using femtosecond laser assisted cataract surgery
    American Journal of Ophthalmology, 2017
    Co-Authors: Soonphaik Chee, Melissa H Y Wong, Aliza Jap
    Abstract:

    Purpose To assess the role of femtosecond laser technology in the management of severely subluxated cataracts. Design Retrospective, interventional case series. Methods All eyes with subluxated cataract seen between July 2012 and June 2015 were assessed for suitability for femtosecond laser–assisted cataract surgery, with the use of capsular tension devices. Participants with subluxated cataracts of at least 6 clock hours of Zonular Weakness were included in the study. Data collected included patient demographics, preoperative and postoperative best-corrected visual acuity (BCVA), nuclear density, extent of Zonular Weakness, completeness of capsulotomy, and complications. Poor visual outcome was defined as BCVA of worse than 20/40. Main outcome measure was the retention of the capsular bag. Results Of the 72 eyes with subluxated cataracts undergoing surgery during the study period, 47 eyes of 47 patients were eligible for analysis. Mean age of the patients was 60.7 years (standard deviation [SD] 13.2 years). The majority were male (32, 68.1%) and Chinese (38, 80.8%). The mean duration of follow-up was 8 months (SD 5.6 months). The main identifiable cause of lens subluxation was trauma (11 eyes). Almost two thirds (30 eyes) had more than 9 clock hours of Zonular Weakness. Seventy percent of cataracts (33) were nuclear sclerosis grade 3 and above. The capsular bag was preserved in 43 eyes (91.5%). The intraocular lens was stable and centered at the last follow-up in all these 43 eyes. An anterior capsule tear occurred in 6 eyes, all of which had cataracts of nuclear sclerosis grade 3 and above, with posterior extension occurring in 3 eyes. Primary posterior capsule rupture occurred in 1 eye. At 1 month 37 eyes (80.4%) had a BCVA of 20/40 or better. There was significant improvement in BCVA at 1 month (mean of 0.92 logMAR units [SD 0.88] to 0.22 [SD 0.38] [ P t test]), which was maintained at 1 year. Conclusions Selected cases of severely subluxated cataracts may be managed using femtosecond laser technology to perform the capsulotomy and nuclear fragmentation, with successful preservation of the capsular bag in 90% of eligible cases, especially in eyes with soft cataracts.

Shigeo Yaguchi - One of the best experts on this subject based on the ideXlab platform.

  • objective classification of Zonular Weakness based on lens movement at the start of capsulorhexis
    PLOS ONE, 2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Tadahiko Kozawa, Yukari Yagiyaguchi, Hiroko Bissenmiyajima
    Abstract:

    Purpose To quantify Zonular Weakness based on lens movement at the start of continuous curvilinear capsulorhexis (CCC) and establish a classification system for it. Setting Kozawa Eye Hospital and Diabetes Center, Mito, Japan. Design Retrospective interventional case series. Methods We examined 402 consecutive eyes of 316 patients who underwent CCC, phacoemulsification and aspiration (PEA), and intraocular lens (IOL) implantation. The movement of the lens capsule was measured using images from video recordings of the CCC procedure. Zonular Weakness was classified based on the shifted distance: Grade I, less than 0.20 mm; Grade II, 0.20–0.39 mm; and Grade III, greater than 0.40 mm. For each of these grades, we examined the use of the capsule stabilization device during PEA, the surgical procedure for lens removal, and IOL fixation. Results We classified 276 eyes (68.6%) as Grade I, 102 eyes (25.4%) as Grade II, and 24 eyes (6.0%) as Grade III. As the grade increased, the use of the capsule stabilization device in PEA and scleral suture fixation of IOL increased. Conclusions Zonular Weakness was quantified by measuring the movement of the lens capsule. An objective classification of Zonular Weakness based on lens movement may be useful for selecting the appropriate device and procedure during cataract surgery.

  • Classification of Zonular Weakness.
    2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Yukari Yagi-yaguchi, Tadahiko Kozawa, Hiroko Bissen-miyajima
    Abstract:

    Classification of Zonular Weakness.

  • Surgical procedure for lens removal.
    2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Yukari Yagi-yaguchi, Tadahiko Kozawa, Hiroko Bissen-miyajima
    Abstract:

    The use of a capsule stabilization device during phacoemulsification and aspiration increased as the Zonular Weakness grade (I–III) increased.

  • Surgical procedure for intraocular lens (IOL) fixation.
    2017
    Co-Authors: Saori Yaguchi, Shigeo Yaguchi, Yukari Yagi-yaguchi, Tadahiko Kozawa, Hiroko Bissen-miyajima
    Abstract:

    The rate of scleral suture fixation of the IOL and scleral suture fixation of the capsule using a modified-capsule expander increased as the Zonular Weakness grade (I–III) increased.

  • objective evaluation of Zonular Weakness measurement of lens movement at the start of capsulorhexis using extracted porcine eyes
    Journal of Clinical & Experimental Ophthalmology, 2016
    Co-Authors: Yukari Yaguchi, Saori Yaguchi, Shigeo Yaguchi, Tadahiko Kozawa, Yuichiro Tanaka, Kazuno Negishi, Kazuo Tsubota
    Abstract:

    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.