Publications

2017

PURPOSE: Advances in surgical techniques allow implantation of intraocular lenses (IOL) with cataract extraction, even in young children. However, there are several challenges unique to the pediatric population that result in greater degrees of postoperative refractive error compared to adults. METHODS: Literature review of the techniques and outcomes of pediatric cataract surgery with IOL implantation. RESULTS: Pediatric cataract surgery is associated with several sources of postoperative refractive error. These include planned refractive error based on age or fellow eye status, loss of accommodation, and unexpected refractive errors due to inaccuracies in biometry technique, use of IOL power formulas based on adult normative values, and late refractive changes due to unpredictable eye growth. CONCLUSIONS: Several factors can preclude the achievement of optimal refractive status following pediatric cataract extraction with IOL implantation. There is a need for new technology to reduce postoperative refractive surprises and address refractive adjustment in a growing eye.
Learned D, Eliott D. Management of Delayed Suprachoroidal Hemorrhage after Glaucoma Surgery. Semin Ophthalmol. 2017;:1–5.
PURPOSE: To review the most current treatment recommendations and outcomes for delayed suprachoroidal hemorrhages. METHODS: Article review of management and outcomes of suprachoroidal hemorrhages, with emphasis on delayed suprachoroidal hemorrhages in the setting of glaucoma surgery. CONCLUSION: Time of drainage of suprachoroidal hemorrhages remains controversial. Earlier drainage should be considered with high intraocular pressure, expulsion of intraocular content, or retinal detachment. In clinically stable eyes with suprachoroidal hemorrhage, recommendations range from observation to immediate drainage. Clot lysis occurs at roughly 14 days.
Marmalidou A, Kheirkhah A, Dana R. Conjunctivochalasis: A Systematic Review. Surv Ophthalmol. 2017;
Conjunctivochalasis (CCH) is a conjunctival condition characterized by loose, redundant conjunctival folds, most typically in the inferior bulbar conjunctiva of both eyes. Although CCH is a common cause of ocular irritation and discomfort, especially in the elderly, it is often overlooked in clinical practice. Conjunctivochalasis may be associated with various ocular and non-ocular conditions; however, the most important risk factor is aging. Although often asymptomatic, CCH may cause symptoms related to tear film instability and/or delayed tear clearance. Pathogenesis of CCH remains largely unknown, but may involve different elements such as aged conjunctiva, unstable tear film, mechanical friction, ocular surface inflammation, and delayed tear clearance. Contradictory results have been reported on histopathologic changes in CCH, with some studies showing a normal microscopic structure. For symptomatic CCH, medical treatment may include lubrication and anti-inflammatory medications. For symptomatic patients who fail to respond to medical treatment, a surgical procedure may be considered. Although various surgical procedures have been used for CCH, more often it consists of conjunctival cauterization or excision of the redundant conjunctiva, with or without amniotic membrane transplantation.
Peterson S, Silva P, Murtha T, Sun J. Cataract Surgery in Patients with Diabetes: Management Strategies. Semin Ophthalmol. 2017;:1–8.
Diabetes is a chronic systemic disease that affects nearly one in eight adults worldwide. Ocular complications, such as cataract, can lead to significant visual impairment. Among the worldwide population, cataract is the leading cause of blindness, and patients with diabetes have an increased incidence of cataracts which mature earlier compared to the rest of the population. Cataract surgery is a common and safe procedure, but can be associated with vision-threatening complications in the diabetic population, such as diabetic macular edema, postoperative macular edema, diabetic retinopathy progression, and posterior capsular opacification. This article is a brief review of diabetic cataract and complications associated with cataract extraction in this population of patients.
Rahman S, Turalba A. Anticoagulation in Glaucoma Surgery. Semin Ophthalmol. 2017;:1–4.
Anticoagulation medications are used commonly, particularly in an elderly population. There are many systemic diseases and scenarios that require modulation of coagulation to prevent serious adverse outcomes. While there is some consensus about their use in cataract surgery, there is less certainty about their management with glaucoma surgery. Glaucoma surgery presents a unique challenge when considering anticoagulation. Currently, there is great diversity in surgeon practices regarding anticoagulation in glaucoma surgery. Based on available evidence, it is unclear whether it is beneficial to hold anticoagulation, with or without bridging therapy, leading up to a planned surgery. Considering the potential serious adverse outcomes related to holding anticoagulation therapy, altering these medications for glaucoma surgery should be done sparingly and in consultation with the primary prescriber of such medications.
Postoperative endophthalmitis is one of the most feared complications of intraocular surgery. The most common types of intraocular surgeries performed worldwide are cataract extraction, glaucoma drainage implants/trabeculectomy, and pars plana vitrectomy. This review will focus on the clinical features, risk factors, prophylaxis, and treatment of endophthalmitis in these three main intraocular surgeries.
Riau A, Venkatraman S, Dohlman C, Mehta J. Surface Modifications of the PMMA Optic of a Keratoprosthesis to Improve Biointegration. Cornea. 2017;36 Suppl 1:S15-S25.
Biointegration of a keratoprosthesis (KPro) is critical for the mitigation of various long-term postoperative complications. Biointegration of a KPro occurs between the haptic skirt (corneal graft) and the central optic [poly(methyl methacrylate) (PMMA)]. Various studies have highlighted common problems associated with poor bonding and biointegration between these 2 incompatible biomaterials. Resolution of these issues could be achieved by surface modification of the inert material (PMMA). A calcium phosphate (CaP) coating deposited on dopamine-activated PMMA sheets by simulated body fluid incubation (d-CaP coating) was shown to improve adhesion to collagen type I (main component of corneal stroma) compared with untreated PMMA and PMMA with other surface modifications. However, the d-CaP coating could easily undergo delamination, thereby reducing its potential for modification of KPro optical cylinders. In addition, the coating did not resemble the Ca and P composition of hydroxyapatite (HAp). A novel dip-coating method that involves the creation of cavities to trap and immobilize HAp nanoparticles on the PMMA surface was introduced to address the problems associated with the d-CaP coating. The newly obtained coating offered high hydrophilicity, resistance to delamination, and preservation of the Ca and P composition of HAp. These advantages resulted in improved adhesion strength by more than 1 order of magnitude compared with untreated PMMA. With respect to biointegration, human corneal stromal fibroblasts were able to adhere strongly and proliferate on HAp-coated PMMA. Furthermore, the new coating technique could be extended to immobilization of HAp nanoparticles on 3-mm-diameter PMMA cylinders, bringing it closer to clinical application.
Roh M, Lee NG, Miller J. Complications Assoicated with MIRAgel for Treatment of Retinal Detachment. Semin Ophthalmol. 2017;:1–6.
MIRAgel (MIRA, Waltham, MA) is a hydrogel buckle that was introduced in 1979 as a new scleral implant for the treatment of retinal detachment. Long-term follow-up of more than 10 years revealed that the hydrolysis of the synthetic hydrophilic material leads to marked expansion of the substance, causing complications such as buckle extrusion and intrusion, eye motility disorder, cosmetic deformities, and periocular infections. Removal of the implant is the treatment of choice in cases with complications, but it is technically difficult due to the friability of the implant, severe scleral ectasia, and relatively high rate of redetachment after removal.
Starks V, Freitag S. Postoperative Complications of Dermis-Fat Autografts in the Anophthalmic Socket. Semin Ophthalmol. 2017;:1–4.
Reconstruction of the anophthalmic socket allows the use of an ocular prosthesis and rehabilitation of facial appearance. Dermis-fat grafting is one option in volume augmentation of the anophthalmic socket and presents unique benefits, including increased surface area within the socket and the ability to grow with pediatric patients. Postoperative complications of this procedure are relatively common. Minor complications, such as graft hirsutism, keratinization, and conjunctival cysts or granulomas, are managed easily by observation or simple intervention. Major complications, such as graft atrophy, infection, or ulceration, may prevent good prosthesis fit and may require return to the operating room.
Thomson B, Souma T, Tompson S, Onay T, Kizhatil K, Siggs O, Feng L, Whisenhunt K, Yanovitch T, Kalaydjieva L, Azmanov D, Finzi S, Tanna C, Hewitt A, Mackey D, Bradfield Y, Souzeau E, Javadiyan S, Wiggs J, Pasutto F, Liu X, John S, Craig J, Jin J, Young T, Quaggin S. Angiopoietin-1 is required for Schlemm’s canal development in mice and humans. J Clin Invest. 2017;
Primary congenital glaucoma (PCG) is a leading cause of blindness in children worldwide and is caused by developmental defects in 2 aqueous humor outflow structures, Schlemm's canal (SC) and the trabecular meshwork. We previously identified loss-of-function mutations in the angiopoietin (ANGPT) receptor TEK in families with PCG and showed that ANGPT/TEK signaling is essential for SC development. Here, we describe roles for the major ANGPT ligands in the development of the aqueous outflow pathway. We determined that ANGPT1 is essential for SC development, and that Angpt1-knockout mice form a severely hypomorphic canal with elevated intraocular pressure. By contrast, ANGPT2 was dispensable, although mice deficient in both Angpt1 and Angpt2 completely lacked SC, indicating that ANGPT2 compensates for the loss of ANGPT1. In addition, we identified 3 human subjects with rare ANGPT1 variants within an international cohort of 284 PCG patients. Loss of function in 2 of the 3 patient alleles was observed by functional analysis of ANGPT1 variants in a combined in silico, in vitro, and in vivo approach, supporting a causative role for ANGPT1 in disease. By linking ANGPT1 with PCG, these results highlight the importance of ANGPT/TEK signaling in glaucoma pathogenesis and identify a candidate target for therapeutic development.