[Current treatments for corneal neovascularization]. / Traitements actuels de la néovascularisation cornéenne.

The extension of blood vessels into the normally avascular stroma defines corneal neovascularization. Though this phenomenon, pathophysiological and clinical features are well characterized, therapeutic modalities have been hindered by a lack of safe, efficacious and non-controversial treatments. In this literature review, we focus on available therapeutic options in light of recent evidence provided by animal and clinical studies. First, this review will focus on pharmacological treatments that target angiogenesis. The low cost and market availability of bevacizumab make it the first anti-angiogenic therapy choice, and it has demonstrable efficacy in reducing corneal neovascularization when administered topically or subconjunctivally. However, novel anti-angiogenic molecules targeting the intracellular pathways of angiogenesis (siRNA, antisense oligonucleotides) provide a promising alternative. Laser therapy (direct photocoagulation or photo-dynamic therapy) and fine needle diathermy also find a place in the treatment of stabilized corneal neovascularization alone or in association with anti-angiogenic therapy. Additionally, ocular surface reconstruction using amniotic membrane graft or limbal stem cell transplantation is essential when corneal neovascularization is secondary to primary or acquired limbal deficiency.

Visual outcomes with flow-diverter stents covering the ophthalmic artery for treatment of internal carotid artery aneurysms.

BACKGROUND AND PURPOSE: Flow-diverting stents can be used to treat intracranial aneurysms that are not amenable to treatment with coils. We analyzed ophthalmic consequences due to coverage of the origin of the ophthalmic artery by flow-diverting stents for the treatment of internal carotid artery aneurysms. MATERIALS AND METHODS: From April 2009 to April 2013, the clinical and angiographic outcomes of all 28 patients treated for aneurysms with flow-diverting stents covering the origin of the ophthalmic artery were prospectively collected. The origin of the ophthalmic artery in relation to the target aneurysm was classified by using a 4-type classification. A complete ophthalmic examination was performed by a single ophthalmologist 48 hours before and 1 week after covering the ophthalmic artery. RESULTS: Ophthalmic artery patency was normal at the end of endovascular treatment in 24/28 cases (85.7%). With extensive ophthalmic examinations, 11 patients (39.3%) showed new ophthalmic complications. Patients with the ophthalmic artery originating from the aneurysm sac were at high risk for retinal emboli (4/5, 80%). Patients with the ophthalmic artery originating from the inner curve of the carotid siphon were at high risk for optic nerve ischemic atrophy (3/4, 75%). CONCLUSIONS: This prospective study shows that covering the ophthalmic artery with a flow-diverting stent is not without potential complications. Ophthalmic complications can occur but are often not diagnosed. The anatomic disposition of the ophthalmic artery in relation to the carotid siphon and aneurysm should be clearly understood because some configurations have a higher risk. When not required, covering of the ophthalmic artery by flow-diverting stents should be avoided.

Involvement of MMP-12 and phosphodiesterase type 4 in cigarette smoke-induced inflammation in mice.

The aim of the present study was to characterise a mouse model of airways inflammation induced by cigarette smoke and to compare it with a lipopolysaccharide (LPS) model with regards to the efficacy of a PDE4 inhibitor (cilomilast), a corticosteroid (dexamethasone) and macrophage metalloelastase (MMP)-12 gene deletion. Cigarette smoke exposure for 3 days induced a time-dependent airway neutrophilia associated with an increased level of keratinocyte-derived chemokine (KC), macrophage inflammatory protein (MIP)-2, MIP-1alpha and MMP-9 in the bronchoalveolar lavage (BAL). LPS exposure also induced an increase in the number of neutrophils in BAL. Studies in MMP-12-/- mice showed that in contrast to the smoking model, MMP-12 did not have a critical role in LPS-induced inflammation. Both cilomilast and dexamethasone blocked LPS-induced neutrophilia in a dose-dependent manner. Cilomilast inhibited cigarette smoke-induced neutrophilia and MIP-1alpha, but only 10 mg.kg(-1) of dexamethasone was effective. Both anti-inflammatory treatments had no effect on the levels of KC and MIP-2 in the BAL. Although the inflammatory response was very similar in the smoking model and LPS, the pharmacological modulation and the MMP-12 gene deletion highlighted the differences in the mechanisms involved. Furthermore, the cigarette smoke model seemed to better represent the situation described in chronic obstructive pulmonary disease patients. In conclusion, these differences underline the importance of using an acute smoke-exposure model to investigate potential new treatments for chronic obstructive pulmonary disease.

Efficient reduction of interactions in dispersion-managed links through in-line filtering and synchronous intensity modulation.

The effect of combined use of in-line filtering and synchronous intensity modulation on interactions is investigated both analytically and numerically in a 40-Gbit/s dispersion-managed link. Numerical results confirm analytical predictions and show that interactions are efficiently suppressed.

Recovered efficiency of filter control in dispersion-managed solitons for optical regeneration applications: analysis and experimental validation.

We demonstrate numerically that local conversion of dispersion-managed return-to-zero pulses into nonlinear Schrödinger solitons fully restores optical filtering control for energy stabilization, thus permitting the association of optical regeneration with dispersion-managed propagation. Experimental validation is achieved by means of 40-Gbit/s regenerated dispersion-managed loop transmission over 10,000 km.

Stability and optimization of dispersion-managed soliton control.

Dispersion-managed solitons with in-line all-optical regeneration are shown to be subject to amplitude and timing-jitter instabilities. We identify and discuss the different natures of these instabilities by means of a linear stability analysis, which is in good agreement with the full numerical solutions of the governing equations. Stable pulse propagation can be achieved through appropriate choices of dispersion map and pulse energy.

Feasibility of 1-Tbit/s (25 x 40 Gbit/s) transoceanic optically regenerated systems.

The feasibility of 1-Tbit/s transoceanic systems based on in-line optical regeneration of 40-Gbit/s channels is numerically investigated. The roles of fiber dispersion, fiber mode area, and channel and regenerator spacings are analyzed, and the corresponding operating ranges for error-free transmission are determined. The results represent a first step in designing multi-terabit-per-second global transmission systems based on realistic components and parameters.

Effect of synchronous modulation on the soliton optical phase.

We show that soliton regeneration through synchronous modulation reduces both amplitude and optical phase noise in a squeezinglike fashion. However, control of optical phase noise is found not to be sufficient to permit error-free phase-shift-keyed soliton transmission, as confirmed by numerical simulations.

Synchronous in-line regeneration of wavelength-division multiplexed solitons signals in optical fibers.

A new synchronization technique for simultaneous in-line modulation and regeneration of wavelength-division multiplexed (WDM) soliton signals in optical fibers is proposed. A specific wavelength-mapping rule makes synchronization compatible with frequency-guiding Fabry-Perot filters. As an example, a 4 x 10 Gbitys WDM regenerated soliton system is demonstrated numerically. We also show that the technique is fully compatible with dispersion management, which alleviates detrimental WDM collisions. Thus the possibility of combining wavelength-division multiplexing and regeneration opens up new perspectives for ultrahigh-bit-rate transoceanic soliton systems.

Factors influencing intentions of pregnant women to exercise after giving birth.

The aim of this study was to identify factors that may influence a pregnant woman's decision to exercise after giving birth. A sample of 98 pregnant women were asked to complete a questionnaire investigation attitudes, social norms, perceived barriers to exercise, and intention regarding exercising after giving birth. Also determined were age, education level, exercise habits, number of months elapsed since onset of present pregnancy, and number of children. The regressions of intentions to exercise on all variables yielded R2 of 0.52 for nulliparous and 0.60 for pluriparous pregnant women. Important differences in variables that explained intentions were found between both groups of women, with perceived barriers to exercise being a key predictor that was, in turn, influenced by previous experience with pregnancy. It is suggested that the experience of the postnatal period modifies the interrelation between the variables explaining intentions regarding exercise after giving birth. Consequently, the programs should take into account the impact that the birth of a first child will have on the perceived barriers to exercise.