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Pars plana lensectomy
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
Andrew W Eller, Brian B Berger
The quarters of the nucleus are rotated with the iris sweep and fragmentation tip, and each one is removed separately. The iris sweep is used to manipulate the nucleus, and can be placed under or over the nuclear fragments to protect the lens capsule from the fragmentation needle. Preservation of the anterior lens capsule protects the corneal endothelium, and can be used for placement of a posterior chamber IOL. Maintenance of the posterior lens capsule prevents lens fragments from falling onto the retina (Fig. 15.5).
SKILL Biometry
Published in Sam Evans, Patrick Watts, Ophthalmic DOPS and OSATS, 2014
Previously the gold-standard technique for AL measurement, contact A-scan biometry is now reserved for those cases for which optical systems are not appropriate (dense cataract, corneal opacities). In contact A-scanning, the probe is placed on the anesthetised cornea and the distance from the probe and the echo from the RPE is measured. A contact A-scan trace demonstrates five spikes (cornea, anterior lens capsule, posterior lens capsule, RPE and sclera) in the phakic eye.
Secondary Open-Angle Glaucomas
Published in Neil T. Choplin, Carlo E. Traverso, Atlas of Glaucoma, 2014
Jonathan Myers, L. Jay Katz, Anand Mantravadi
The classic finding in exfoliation syndrome is the grayish-white flaky material on the anterior lens capsule (Figures 10.8 and 10.9). This material may also be seen at the pupil margin, corneal endothelium, trabecular meshwork, zonular fibers, and ciliary body; after cataract extraction, it appears on the posterior capsule, intraocular lens, and vitreous face as well. This same material has been found in the conjunctiva, orbital blood vessels, skin, myocardium, lung, liver, gallbladder, kidney, and cerebral meninges, usually localized to connective tissue.
Ocular Trauma in Operation Iraqi Freedom and Operation Enduring Freedom from 2001 to 2011: A Bayesian Network Analysis
Published in Ophthalmic Epidemiology, 2021
Morgan M. Harvey, Grant A. Justin, Daniel I. Brooks, Denise S. Ryan, Eric D. Weichel, Marcus H. Colyer
To learn the relationships between the variables in the dataset, a Bayesian Network Analysis was completed. First, we created a set of variable layers, in which lower level layers could logically inform higher level layers. Pooled variables within layers were defined using features defined by either a single variable or multiple variables from the WROTD (Table 2). The first layer of features included gender, whether or not the patient was wearing eye protection (EyeProt), and the geographic location of the injury (LocatInj; Iraq or Afghanistan). The second layer defined eight pooled injury categories (Plastic, Neuro-ophthalmic [Neuro], Cornea, Anterior Segment, Retina, Posterior Segment, Lens, and Associated Injury). The third layer included seven pooled surgical procedures Enucleation [Enucleation], Strabismus Surgery [StrabSurg], cataract extraction and posterior capsule intraocular lens placement [CEPCIOL], oculoplastic surgery (FX_Lid_Lac), vitreoretinal surgeries [PPV], penetrating keratoplasty [PKP], and glaucoma tube shunt placement [TubeShunt]). Finally, the last layer included the final visual outcome of the patient, grouped into some visual acuity (Grades 1, 2, or 3) and no visual acuity (Grades 4 or 5). A network blacklist was created which explicitly excluded from possible consideration any illogical (or backwards) associations; e.g., final visual outcome could never causally predict gender; or a particular type of surgery could never predict an incipient diagnosis.
The red lens: a case of florid lens neovascularisation
Published in Clinical and Experimental Optometry, 2020
Rupak Roy, Kumar Saurabh, Prashant Srivastava, Swakshyar S Pal, Krishnendu Nandi, Lav Kochgaway, Rupak Kanti Biswas, Sourav Sinha
The lens capsule and lens normally resist neovascularisation. The capsule secretes anti‐endothelial cell inhibitory factors preventing neovascularisation.2015 A breach in the lens capsule may allow entry of inflammatory mediators into the lens substance causing neovascularisation.2015 Longstanding 360 degree posterior synechiae with high intraocular pressure in our case may have caused such a breach in the capsule leading to entry of vascular endothelial growth factor, abundant in a case of neovascular glaucoma leading to lens capsule neovascularisation. Advanced diabetic retinopathy is one of the most common causes of ocular ischaemia and neovascularisation.2016 Neovascular glaucoma requires urgent retinal ablation, failing which the increased intraocular pressure may become intractable leading to florid anterior segment neovascularisation. Delayed presentation for eye care or lack of awareness can result in the rare complication of lens capsule neovascularisation.
The Influence of Type 1 Diabetes Mellitus on Amplitude of Accommodation
Published in Current Eye Research, 2020
Ender Sırakaya, Bekir Küçük, Hatice Aslan Sırakaya
Decreased AA in patients with DM may be due to the altered structures and metabolism of crystalline lens in such patients. Fisher et al. observed that the lens capsule and lens substance lost elasticity in diabetic patients, which consequently impaired their accommodative function.22 Fluctuations in refractive status and visual acuity during the day in such patients can indicate changes in crystalline lens structure.23 Independent of age, lens thickness and the curvature of the anterior and posterior lens surfaces were greater among patients with DM than healthy individuals.6 Although lenticular changes in DM may stem from several conditions, increased glucose concentrations and impaired glucose metabolism are considered to be the chief ones.24 All of those pathological mechanisms may reduce AA in patients with DM at an early age. At the same time, although fasting blood glucose and HbA1c levels have been associated with AA in some studies, we found no relationship between those variables.10,15 Similarly, Braun et al. found no association between AA and hyperglycaemia.16 Because those data indicate a relatively short-term diabetic state, we may not have determined their association. If a relationship between those variables indeed exists, then that hypothesis should be verified by monitoring patients with DM in longitudinal studies, given the dynamism of accommodative functions.