No abstract

The new term Flammer syndrome describes a phenotype characterized by the presence of primary vascular dysregulation together with a cluster of symptoms and signs that may occur in healthy people as well as people with disease. Typically, the blood vessels of the subjects with Flammer syndrome react differently to a number of stimuli, such as cold and physical or emotional stress. Nearly all organs, particularly the eye, can be involved. Although the syndrome has some advantages, such as protection against the development of atherosclerosis, Flammer syndrome also contributes to certain diseases, such as normal tension glaucoma. The syndrome occurs more often in women than in men, in slender people than in obese subjects, in people with indoor rather than outdoor jobs, and in academics than in blue collar workers. Affected subjects tend to have cold extremities, low blood pressure, prolonged sleep onset time, shifted circadian rhythm, reduced feeling of thirst, altered drug sensitivity, and increased general sensitivity, including pain sensitivity. The plasma level of endothelin-1 is slightly increased, and the gene expression in lymphocytes is changed. In the eye, the retinal vessels are stiffer and their spatial variability larger; the autoregulation of ocular blood flow is decreased. Glaucoma patients with Flammer syndrome have an increased frequency of the following: optic disc hemorrhages, activated retinal astrocytes, elevated retinal venous pressure, optic nerve compartmentalization, fluctuating diffuse visual field defects, and elevated oxidative stress. Further research should lead to a more concise definition, a precise diagnosis, and tools for recognizing people at risk. This may ultimately lead to more efficient and more personalized treatment.

Purpose To evaluate the effectiveness of an ab interno subconjunctival gelatin implant as primary surgical intervention in reducing intraocular pressure (IOP) and IOP-lowering medication count in medically uncontrolled moderate primary openangle glaucoma (POAG). Methods In this prospective, non-randomized, open-label, multicenter, 2-year study, eyes with medicated baseline IOP 18-33 mmHg on 1-4 topical medications were implanted with (phaco + implant) or without (implant alone) phacoemulsification. Changes in mean IOP and medication count at months 12 (primary outcomes) and 24, clinical success rate (eyes [%] achieving ≥ 20% IOP reduction from baseline on the same or fewer medications without glaucoma-related secondary surgical intervention), intraoperative complications, and postoperative adverse events were assessed. Results The modified intent-to-treat population included 202 eyes (of 218 implanted). Changes (standard deviation) in mean IOP and medication count from baseline were − 6.5 (5.3) mmHg and − 1.7 (1.3) at month 12 and − 6.2 (4.9) mmHg and − 1.5 (1.4) at month 24, respectively (all P < 0.001). Mean medicated baseline IOP was reduced from 21.4 (3.6) to 14.9 (4.5) mmHg at 12 months and 15.2 (4.2) mmHg at 24 months, with similar results in both treatment groups. The clinical success rate was 67.6% at 12 months and 65.8% at 24 months. Overall, 51.1 (12 months) and 44.7% (24 months) of eyes were medication-free. The implant safety profile compared favorably with that published for trabeculectomy and tube shunts. Conclusions The gelatin implant effectively reduced IOP and medication needs over 2 years in POAG uncontrolled medically, with an acceptable safety profile. ClinicalTrials.gov registration number: NCT02006693 (registered in the USA).

Pericytes are specialized mural cells located at the abluminal surface of capillary blood vessels, embedded within the basement membrane. In the vascular network these multifunctional cells fulfil diverse functions, which are indispensable for proper homoeostasis. They serve as microvascular stabilizers, are potential regulators of microvascular blood flow and have a central role in angiogenesis, as they for example regulate endothelial cell proliferation. Furthermore, pericytes, as part of the neurovascular unit, are a major component of the blood-retina/brain barrier. CNS pericytes are a heterogenic cell population derived from mesodermal and neuro-ectodermal germ layers acting as modulators of stromal and niche environmental properties. In addition, they display multipotent differentiation potential making them an intriguing target for regenerative therapies. Pericyte-deficiencies can be cause or consequence of many kinds of diseases. In diabetes, for instance, pericyte-loss is a severe pathological process in diabetic retinopathy (DR) with detrimental consequences for eye sight in millions of patients. In this review, we provide an overview of our current understanding of CNS pericyte origin and function, with a special focus on the retina in the healthy and diseased. Finally, we highlight the role of pericytes in de- and regenerative processes.

Under flow testing, the XEN micro-fistula implant was able to maintain backpressure above numerical hypotony levels without the use of complex valve systems. This is due to the XEN implant's design, derived from the principles that dictate Newtonian fluids.