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YAG Laser
Published in Anita Prasad, Laser Techniques in Ophthalmology, 2022
PCO occurs in 40–100% of children and young adults after cataract surgery, due to more marked inflammatory and healing responses to a surgical insult. Recent advances in paediatric cataract surgery, with posterior continuous curvilinear capsulorhexis and anterior vitrectomy, have reduced the incidence. PCO is potentially sight threatening in children, due to higher incidence rate, quicker onset, denser opacification, and greater amblyogenic effect on vision.Primary posterior capsulotomy with anterior vitrectomy (during cataract surgery), is the preferred treatment to prevent PCO.If this has not been done, a YAG capsulotomy may be performed in older children.
Removal of intraocular foreign bodies
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
William J Wirostko, Sumit Bhatia, William F Mieler, Cathleen M McCabe
IOFBs located in the anterior chamber are best removed through a secondary limbal incision after the traumatic laceration has been repaired (Fig. 49.4). This limits the trauma to the original laceration and facilitates instrumentation. The secondary incision should be placed 90° away from the IOFB to avoid traversing instruments over the lens capsule. Additional lenticular protection is possible by inducing miosis pharmacologically. The IOFB can be engaged with either intraocular forceps or a rare-earth magnet, while viscoelastics maintain the anterior chamber. Viscoelastic dissection may be helpful for removing an IOFB from the iris. Lens extraction is usually necessary if the IOFB is embedded in the lens.31 Removing the lens in total helps to prevent dropping the IOFB into the posterior segment. If an intralenticular IOFB can be grasped, its extraction should be performed before cataract extraction. An anterior capsular laceration can often be converted into a capsulorhexis and the cataract removed by aspiration. Intraocular lens implantation can be performed concurrently, depending upon the extent of the trauma and the risk of infection.
Accommodating intraocular lenses
Published in Pablo Artal, Handbook of Visual Optics, 2017
The principle of lens refilling is different compared to accommodating IOLs. The idea is to refill the lens capsule after removing the crystalline lens.43 However, as shown in Figure 13.12, lens refilling changed significantly over the years. Primarily, the capsular bag was filled directly (Figure 13.12a), but leakage occurred in many cases. In a next step, different techniques were developed to overcome this problem, such as an endocapsular balloon (Figure 13.12b), which prevented silicone leakage with reasonable preservation of accommodation. Other methods, such as a specially designed sealing plug (Figure 13.12c), and later on an optic plug (Figure 13.12d,e) were also tested. To improve on the endocapsular balloon technique, a plug to seal a continuous curvilinear capsulorhexis was developed by Nishi and Nishi (Figure 13.12f).44 This technique showed to be feasible due to a good outcome concerning centration and only little PCO. A more recent method uses an innovative foldable silicone IOL and a thin plate-disk haptic.45 This technique allows the anterior capsule to cover the injection hole to prevent leakage of the silicone. There are two additional advantages of this technique. The cohesive silicone polymer with its high molecular weight does not leak through the space between the anterior capsule and the IOL and the injected liquid silicone polymerizes 2 h after injecting it; therefore, postoperative leakage is not be expected.46
The effects of trypan blue use on the corneal endothelium during cataract surgery in patients with pseudoexfoliation syndrome (PEX)
Published in Cutaneous and Ocular Toxicology, 2021
Fikret Ucar, Ekrem Kadıoğlu, Lutfi Seyrek
After randomisation was performed using a table of random numbers, the surgeon learned whether to use TB for the anterior capsule staining to the patient. After using 0.5% Proparacaine HCl (Alcain, Alcon) for topical anaesthesia, 1.0 ml, 1% trypan blue (Vision Blue®, DORC, Zuidland, the Netherlands) was injected without air into the anterior chamber via a side port in the study group. After the dye was allowed to remain in the anterior chamber for 10 s, the anterior chamber was washed with the balanced salt solution (BSS), and a dispersive viscoelastic material (hydroxypropyl methylcellulose) was injected. Capsulorhexis was performed. In the control group in which trypan blue was not used, after anterior chamber paracentesis, viscoelastic material was injected and capsulorhexis was performed.
The Development, Growth, and Regeneration of the Crystalline Lens: A Review
Published in Current Eye Research, 2020
The success of Lin et al. does raise questions on how to broaden the applicability of the treatment. None of the patients in the study had traumatic, hereditary, or metabolic cataract. While the Lin study only included patients with idiopathic cataracts, non-idiopathic cataracts comprise over half of all pediatric cataract patients.56,57 Trauma to the lens may damage the capsule and reduce its ability to regenerate the lens and hereditary and metabolic disorders would likely prevent the lens from regenerating itself as well. Using cultured cells would be a potential avenue of research in order to provide source material for a healthy lens when the endogenous cells may be incapable of doing so. Additionally, refilling the emptied capsule with a scaffold would potentially speed up transdifferentiation and prevent adhesion of the anterior and posterior capsules.57 The capsulorhexis technique used by Lin et al. is an important advancement in regenerative ophthalmology and by minimizing damage to the capsule allows for the conditions necessary for lens regeneration to take place and opens up avenues of research.56,57
A Prechop Technique Using a Reverse Chopper
Published in Journal of Investigative Surgery, 2019
Yang Zhao, Jiaxin Li, Ke Yang, Siquan Zhu
After topical anesthesia is administered, a standard 3.0-mm transparent corneal incision is made at the 10 o'clock position of the affected eye. A viscoelastic agent is injected into the anterior chamber, and a standard puncture hole is made at the 2 o'clock position using a 15° puncture scalpel. Continuous circular capsulorhexis is performed along the capsule anterior to the lens using a capsulorhexis forceps. The diameter of the capsule opening is typically 5–6 mm. The reverse chopper is inserted into the anterior chamber from the corneal incision at the 10 o'clock position. The distal end of the hook is pressed downward within the capsule opening to make contact with the nucleus of the lens. The reverse chopper is then tilted and slid into the capsule along the nucleus of lens. The hook is then gradually rotated so that its curved part is placed in the cortical shell located between the nucleus of lens and the capsule. The blade inside its curved end is fixed perpendicular to the equator of the nucleus.