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An Approach to Visual Loss in a Child
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Muhammad Hassaan Ali, Stacy L. Pineles
There is almost 100% rate of posterior capsular opacification in children after cataract surgery. In all such cases, primary posterior capsulotomy and anterior vitrectomy up to the age of 6–7 years are recommended. The anterior vitrectomy removes the solid vitreous base. The pars plana is generally avoided in children since this approach may cause suprachoroidal hemorrhage. Vitrectomy through the limbal side ports is also relatively easier for the surgeons who are trained in the anterior segment. Some surgeons prefer to perform capsulorrhexis of the posterior capsule. In such cases, anterior vitrectomy need not be performed since the vitreous phase is not disturbed. The preferable lens material for IOL in children is either hydrophobic acrylic or polymethyl methacrylate. If the children are cooperative and able to sit properly on slit amp, Nd:YAG laser capsulotomy can be done over 6 years of age after surgery (48).
Simple vitrectomy
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
Alan J Ruby, George A Williams
The vitreous is shaved toward the vitreous base, taking care to reduce any unnecessary traction on the retina. Certain newer vitrectomy machines have cutting rates of 1200–2400 cpm, which may be beneficial in trimming the peripheral vitreous. This procedure is carried out for 360°until a total pars plana vitrectomy is completed.
Anatomy and examination of the eye
Published in Thomas H. Williamson, Vitreoretinal Disorders in Primary Care, 2017
The vitreous base is a zone of adhesion of the vitreous to the retina and pars plana that is 3–4 mm wide and lying across the ora serrata. It is an area of strong adhesion and is not usually separated even in surgical procedures.
Idiopathic Vitritis after Boston Type 1 Keratoprosthesis Implantation: Incidence, Risk Factors and Outcomes in a Multicentric Cohort
Published in Ocular Immunology and Inflammation, 2022
Clemence Bonnet, Ismael Chehaibou, Reza Ghaffari, Nicholas J. Jackson, Cristina Bostan, Jean-Pierre Hubschman, Mona Harissi-Dagher, Anthony J. Aldave
Retinal detachments were more frequent after keratoprosthesis implantation following vitritis than after procedures without vitritis, partially explaining the higher percentage of eyes that lost 20/200 CDVA and experienced KPro retention failure following the development of vitritis.23 The presence of vitreous inflammation may play a role in the occurrence of retinal detachment by enhancing posterior vitreous detachment and morphological changes of the vitreous base, thereby increasing the risk of retinal breaks.24 Given that retinal detachments are more difficult to diagnose and repair following KPro implantation, and are associated with a poor prognosis, some authors have advocated performing a total pars plana vitrectomy at the time of aphakic KPro implantation, although they have not demonstrated a decrease in the incidence of vitritis or retinal detachment when compared to partial pars plana vitrectomy or anterior vitrectomy at the time of KPro implantation.25,26
Vitreomacular disorders: a review of the classification, pathogenesis and treatment paradigms including new surgical techniques
Published in Clinical and Experimental Optometry, 2021
Mali Okada, Daniel Chiu, Jonathan Yeoh
In order to understand the pathogenesis of VMD, it is helpful to consider the normal anatomy and ageing process of the vitreous and its relationship to the VRI. The vitreous is a transparent gelatinous structure composed of a central vitreous body and an outer cortex.1 The vitreous is composed of Type II collagen arranged in parallel fibrils which is separated by water and hyaluronic acid.2 The vitreous cortex is firmly attached to the internal limiting membrane (ILM) of the retina at several points, most notably at the vitreous base, but also at the optic disc, fovea and along major retinal blood vessels.2 The ILM is a trilaminar structure with vitreous collagen cortex, extracellular matrix as an intermediate layer between the basal laminar formed by the Muller cell footplates. This firm adhesion at the vitreous base occurs as collagen fibrils penetrate the basal lamina to integrate with glial cells in this area. In contrast, at the rest of the VRI, collagen fibrils are adherent to the extracellular matrix on the basal lamina.
Advances in the tools and techniques of vitreoretinal surgery
Published in Expert Review of Ophthalmology, 2020
Ashish Markan, Aman Kumar, Jayesh Vira, Vishali Gupta, Aniruddha Agarwal
While performing vitrectomy, one of the commonly encountered challenge is dissection of tissues very close to the retinal surface because it has an inherent risk of aspirating and resulting in retinal breaks and hemorrhages. The surgical challenge is compounded in the vitreous base or area over the detached retina since these areas are especially prone to iatrogenic tears. Generally, the surgeons tend to decrease the aspiration rate and increase the cut rate. The ULTRAVIT 10 K® (Alcon) has beveled tip and delivers 10,000 cuts per minute (cpm) via dual pneumatic drive technology in 23+, 25+, 27+ gauge series (Figure 2). It is used with the CONSTELLATION® system (ALCON) with the latest software update. The distance between the probe end and the opening is shorter (measuring 0.009 inches compared to 0.016–0.021 inches in conventional probes) reducing the cutting port and retina distance by approximately 50% [22].