Is there a fetal origin of peripheral vascular disease?

Does the Presence of the Cilioretinal Artery Affect the Incidence, Clinical Picture and Progression of Age-Related Macular Degeneration?

The aims of this study were to analyze the relationship between the presence of the cilioretinal artery (CRA) and the incidence, severity and progression of age-related macular degeneration (AMD) and to estimate the influence of the CRA on choroidal and retinal parameters. A total of 287 patients with AMD and 110 healthy controls were enrolled in the study. CRA occurrence was determined using color fundus images. AMD progression was assessed after 3 years. There was no difference in the incidence of CRA between the AMD and control groups (23.34% vs. 24.55%; p = 0.8). Lower-stage AMD was more frequently observed in eyes with the CRA than in eyes without the artery (p = 0.016). The CRA did not influence disease progression (p = 0.79). The CRA did not influence retinal and choroidal thickness and volume parameters or the retinal vessel caliber and functionality in either the AMD or control groups. There was no relationship between CRA presence and CFH Y402H and ARMS2 A69S risk variants. The results did not show a protective effect of the CRA on the incidence and progression of AMD. The CRA may affect the severity of AMD; however, the mechanism of this phenomenon is unclear.

Quantitative evaluation of graded hindlimb ischemia based on pharmacokinetic modelling and hemodynamic analysis of indocyanine green

OBJECTIVE

Accurate evaluation of the degree of hindlimb ischemia is challenging but essential for the diagnosis and treatment of peripheral vascular insufficiency. The aim of the study is to apply a multiparametric method for the quantitative estimation of mouse models with different degrees of hindlimb ischemia based on a dynamic fluorescence imaging-based strategy.

APPROACH

An adjustable hydraulic occluder was placed around the thigh root of one hindlimb to induce six different degrees of hindlimb ischemia. Five parameters were extracted to quantitatively evaluate the degree of ischemia, including perfusion rate (PR) and perfusion vascular density (PVD) from a mathematical model of indocyanine green (ICG) pharmacokinetics, rising time (T _rise), blood flow index (BFI) and mean fluorescence intensity (MFI) from time-series analysis of ICG hemodynamics.

MAIN RESULTS

The results showed that the normalized PR and BFI decreased while the normalized T _rise increased progressively with the degree of ischemia. The normalized PVD and MFI first increased and then decreased with the degree of ischemia. High correlation was observed between the degree of ischemia and the arterial oxygen saturation which was measured by an oximeter.

SIGNIFICANCE

The results of this work demonstrated that PR, BFI and T _rise can be used for the quantitative and comprehensive evaluation of graded hindlimb ischemia.

Effects of temperature on multiparametric evaluation of hindlimb ischemia with dynamic fluorescence imaging

Quantitative evaluation of hindlimb ischemia is essential for early diagnosis and therapy of peripheral arterial disease (PAD). Dynamic imaging using near-infrared (NIR) fluorophore indocyanine green (ICG) is a noninvasive and effective tool to monitor multiple vascular parameters including perfusion rate (PR), perfusion vascular density (PVD) and hemodynamics. It has been previously demonstrated that temperature changes could lead to significant variations of blood flow rate and vascular perfusion. In this paper, multiparametric evaluation of hindlimb ischemia was performed at different temperatures. Five different parameters were extracted from dynamic fluorescence imaging, including PR, PVD, rising time (T_rise ), blood flow index (BFI) and mean fluorescence intensity (MFI). Temperatures varied from 15 °C to 40 °C were set on a mouse model of hindlimb ischemia. The aforementioned five parameters were obtained at each temperature. The results suggest that PVD, BFI and MFI could be effective indicators to distinguish ischemic tissues from normal tissues in mouse hindlimb at different temperatures. In contrast, PR is effective only when the temperature is higher than 25 °C, while T_rise is effective only when the temperature is lower than 35 °C. The parameters of PVD, BFI and MFI could provide quantitative and comprehensive evaluation for PAD at different temperatures. (A) Bright-field image of the normal (left) and ischemic (right) hindlimbs. (B-D) Parametric images of perfusion vascular density, blood flow index and mean fluorescence intensity.

Placental characteristics and birthweight

Standard gross placental measures capture dimensions relevant to specific placental functions. Our objective was to determine their accountability independent of placental weight for variance in birthweight, an important proxy for intrauterine 'adequacy' in fetal origins studies. The sample consisted of 24 152 singleton liveborn children of the Collaborative Perinatal Project delivered from 34 to 42 completed weeks gestation, with complete data for six placental measures (placental disc shape, umbilical cord length, distance from cord insertion to nearest margin, large diameter, small diameter, placental thickness) and placental weight. Associations between birthweight and placental measures were examined using multiple linear regression. Placental weight alone accounted for 36.6% of birthweight variation; the six other placental measures accounted for 28.1%. Combined, all placental measures accounted for 39.1% of birthweight variation. Seven maternal characteristics (age, height, weight, parity, socio-economic status, cigarette use, and race) were investigated to determine whether their known associations with birthweight were mediated by placental markers. Analysis suggested that the impact of all maternal characteristics except smoking was consistent with mediation by placental characteristics.