BACKGROUND: Revesz syndrome is a telomere disorder in the dyskeratosis congenita (DKC) spectrum characterized by exudative retinopathy, bone marrow failure, neuroradiographic abnormalities, and integumentary findings. MATERIALS/METHODS: We report the ophthalmologic findings, documented by examinations under anesthesia with clinical photography and fluorescein angiography, as well as the systemic manifestations and genetic and molecular testing, in identical twins with Revesz syndrome, and compare and contrast these features to those of other pediatric retinal vasculopathies. RESULTS: Both twins exhibited widespread avascularity and anomalous vasculature of the retinal periphery, retinal telangiectasias, and exudation. One twin developed a combination exudative/tractional/rhegmatogenous retinal detachment, while the other exhibited a focal collection of buds of retinal neovascularization. Both twins developed bone marrow failure and were found to have cerebellar hypoplasia and widespread cerebral calcifications. Telomere testing in lymphocytes and granulocytes revealed telomere length less than the 1st percentile for age, and gene sequencing revealed a novel mutation in the TINF2 gene, resulting in the T284P TIN2 protein variant. CONCLUSIONS: We report ophthalmic findings in twins with Revesz syndrome due to a previously unreported mutation in TINF2 and propose that phenotypic and molecular overlaps between DKC spectrum disorders and pediatric retinal vasculopathies may reflect a shared pathophysiologic basis.
Publications
2017
PURPOSE: To investigate the levels of neutrophil elastase (NE), matrix metalloproteinases (MMPs), and myeloperoxidase (MPO) in tear washes of patients with ocular graft-vs-host disease (oGVHD). DESIGN: Case-control study. METHODS: Based on established criteria, oGVHD patients (n = 14; 28 eyes) and age-/sex-matched healthy controls (n = 14; 28 eyes) were enrolled. Tear washes were collected and analyzed for NE using a single-analyte enzyme-linked immunosorbent assay (ELISA). MMPs (1, 2, 3, 7, 8, 9, 12), MPO, and tissue inhibitor of matrix metalloproteinase (TIMP)-1 were analyzed using multianalyte bead-based ELISA assays. Total MMP activity was measured using a fluorimetric assay. Correlation studies were performed between NE, MMP-8, MMP-9, and MPO within study groups. RESULTS: NE, MMP-8, MMP-9, and MPO levels were elevated in oGVHD tears when compared with controls (P < .0001). NE was the most elevated analyte. MMP activity was higher and TIMP-1 levels were lower in oGVHD than in control (P < .0001). In oGVHD, NE significantly correlated with MMP-8 (r = 0.92), MMP-9 (r = 0.90), and MPO (r = 0.79) (P < .0001). MMP-8 correlated with MMP-9 (r = 0.96, P < .0001), and MPO (r = 0.60, P = .001). MMP-9 correlated with MPO (r = 0.55, P = .002). In controls, NE, MMP-9, and MPO significantly correlated with each other (P < .0001). CONCLUSIONS: The marked increase in NE in oGVHD tears that correlated strongly with elevated MMP-8, MMP-9, and MPO suggests a common neutrophilic source and provides evidence of neutrophil activity on the ocular surface of oGVHD patients.
Diabetes mellitus is a chronic disease that affects 415 million people worldwide. Despite treatment advances, diabetic eye disease remains a leading cause of vision loss worldwide. Diabetic macular edema (DME) is a common cause of vision loss in diabetic patients. The pathophysiology is complex and involves multiple pathways that ultimately lead to central retinal thickening and, if untreated, visual loss. First-line treatment of DME has evolved from focal/grid laser established by the Early Treatment of Diabetic Retinopathy Study (ETDRS) to intravitreous pharmacologic therapy. Landmark prospective clinical trials examining the effect of intravitreous injections of vascular endothelial growth factor (VEGF) inhibitors in the treatment of DME have demonstrated improved visual outcomes over focal grid laser. This review focuses on the scientific evidence treatment of DME, disease pathophysiology, clinical disease course, current treatment standards, and emerging novel therapeutic approaches.
The optic nerve has been widely used to investigate factors that regulate axon regeneration in the mammalian CNS. Although retinal ganglion cells (RGCs), the projection neurons of the eye, show little capacity to regenerate their axons following optic nerve damage, studies spanning the 20(th) century showed that some RGCs can regenerate axons through a segment of peripheral nerve grafted to the optic nerve. More recently, some degree of regeneration has been achieved through the optic nerve itself by factors associated with intraocular inflammation (oncomodulin) or by altering levels of particular transcription factors (Klf-4, -9, c-myc), cell-intrinsic suppressors of axon growth (PTEN, SOCS3), receptors to cell-extrinsic inhibitors of axon growth (Nogo receptor, LAR, PTP-σ) or the intracellular signaling pathway activated by these receptors (RhoA). Other regulators of regeneration and cell survival continue to be identified in this system at a rapid pace. Combinatorial treatments that include two or more of these factors enable some retinal ganglion cells to regenerate axons from the eye through the entire length of the optic nerve and across the optic chiasm. In some cases, regenerating axons have been shown to innervate the appropriate central target areas and elicit postsynaptic responses. Many discoveries made in this system have been found to enhance axon regeneration after spinal cord injury. Thus, progress in optic nerve regeneration holds promise not only for visual restoration but also for improving outcome after injury to other parts of the mature CNS.
Interventions in the treatment of mild to moderate glaucoma have evolved to include a group of procedures collectively named "Minimally Invasive Glaucoma Surgery (MIGS)." These procedures are less invasive than traditional filtering surgery and setons and offer the benefit of an improved side-effect profile. A review of current published literature has shown that these procedures offer lower intraocular pressure, decrease reliance on topical medications, have no negative effect on refractive outcomes, and can be safely done following failed tube surgery.
In vivo confocal microscopy (IVCM) is becoming an indispensable tool for studying corneal physiology and disease. Enabling the dissection of corneal architecture at a cellular level, this technique offers fast and noninvasive in vivo imaging of the cornea with images comparable to those of ex vivo histochemical techniques. Corneal nerves bear substantial relevance to clinicians and scientists alike, given their pivotal roles in regulation of corneal sensation, maintenance of epithelial integrity, as well as proliferation and promotion of wound healing. Thus, IVCM offers a unique method to study corneal nerve alterations in a myriad of conditions, such as ocular and systemic diseases and following corneal surgery, without altering the tissue microenvironment. Of particular interest has been the correlation of corneal subbasal nerves to their function, which has been studied in normal eyes, contact lens wearers, and patients with keratoconus, infectious keratitis, corneal dystrophies, and neurotrophic keratopathy. Longitudinal studies have applied IVCM to investigate the effects of corneal surgery on nerves, demonstrating their regenerative capacity. IVCM is increasingly important in the diagnosis and management of systemic conditions such as peripheral diabetic neuropathy and, more recently, in ocular diseases. In this review, we outline the principles and applications of IVCM in the study of corneal nerves in various ocular and systemic diseases.
Leber congenital amaurosis (LCA) is a group of severe inherited retinal dystrophies that lead to early childhood blindness. In the last decade, interest in LCA has increased as advances in genetics have been applied to better identify, classify, and treat LCA. To date, 23 LCA genes have been identified. Gene replacement in the RPE65 form of LCA represents a major advance in treatment, although limitations have been recognized. In this article, we review the clinical and genetic features of LCA and evaluate the evidence available for gene therapy in RPE65 disease.
