Corpus luteum number and the maternal renin-angiotensin-aldosterone system as determinants of utero-placental (vascular) development: the Rotterdam Periconceptional Cohort

Background Pregnancies with > 1 corpus luteum (CL) display a hyperdynamic circulation and an increased risk of small-for-gestational age deliveries. Among the factors released by the CL is prorenin, the inactive precursor of renin. Since the renin-angiotensin-aldosterone system (RAAS) is involved in early hemodynamic pregnancy adaptation, we linked both CL number and first-trimester concentrations of prorenin (as an indicator of RAAS activity) and the aldosterone/renin ratio (as an indicator of angiotensin-independent aldosterone effectiveness) to non-invasive markers of utero-placental (vascular) development, measured longitudinally from the first trimester onwards. Methods A total of 201 women, who conceived naturally or after in-vitro fertilization treatment (with 0 (n = 8), 1 (n = 143), or > 1 (n = 51) CL), were selected from the Rotterdam Periconceptional Cohort. Maternal RAAS components were determined at 11 weeks gestation. Placental volume and utero-placental vascular volume were measured from transvaginal 3D ultrasound scans at 7, 9 and 11 weeks gestation, pulsatility and resistance indices of the uterine arteries were assessed by pulsed wave Doppler ultrasounds at 7, 9, 11, 13, 22 and 32 weeks gestation. At birth placental weight was obtained using standardized procedures. Results Pregnancies without a CL show lower uterine artery indices throughout gestation than 1 CL and > 1 CL pregnancies, while parameters of placental development are comparable among the CL groups. After adjustment for patient- and treatment-related factors, first-trimester prorenin concentrations are positively associated with uterine artery pulsatility and resistance indices (β 0.06, 95% CI 0.01;0.12, p = 0.04 and β 0.10, 95% CI 0.01;0.20, p = 0.04, respectively), while high prorenin concentrations are negatively associated with first-trimester utero-placental vascular volume (β -0.23, 95% CI -0.44;-0.02, p = 0.04) and placental weight (β -93.8, 95%CI -160.3;-27.4, p = 0.006). In contrast, the aldosterone/renin ratio is positively associated with first-trimester placental volume (β 0.12, 95% CI 0.01;0.24, p = 0.04). Conclusions The absence of a CL, resulting in low prorenin concentrations, associates with low uterine artery pulsatility and resistance, while high prorenin concentrations associate with a low utero-placental vascular volume and weight. These data support a scenario in which excess prorenin, by upregulating angiotensin II, increases uterine resistance, thereby preventing normal placental (vascular) development, and increasing the risk of small-for-gestational age deliveries. Simultaneously, high aldosterone concentrations, by ensuring volume expansion, exert the opposite.

Pulmonary Vascular Volume is Associated With DLCO and Fibrotic Score in Idiopathic Pulmonary Fibrosis: An Observational Study

Background: Idiopathic pulmonary fibrosis (IPF) is primarily a disease of old age. However, it is difficult to diagnose and has a complex disease course. High-resolution computed tomography (HRCT) and lung function test are crucial for its diagnosis and follow-up. However, the correlation of HRCT findings to lung function test results was not extensively investigated.Methods: This study retrospectively analysed the medical records and images of patients with IPF. Patients with evident emphysema and lung cancer were excluded. All included cases would be investigated through a multidiscipline discussion to confirm the diagnosis. The correlation of CT findings including fibrotic score, CT lung volume, pulmonary artery trunk (PA) diameter and pulmonary vascular volume (PVV) to the lung function test such as forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO) was analysed.Results: A total of 32 patients were included. The fibrotic score and PVV were significantly correlated with DLCO (r = 0.59, p = 0.01; r = −0.43, p = 0.03, respectively) but not with FVC. The PVV was significantly correlated with fibrotic score (r = 0.59, p<0.01) and PA diameter (r = 0.47, p = 0.006).Conclusion: Our study shows the structural and functional correlation of IPF. The extent of lung fibrosis (fibrotic score) and PVV were associated with DLCO but not with FVC, especially for patients with IPF without significant FVC deficiency. The PA diameter, which reflects the pulmonary artery pressure, was associated with PVV.

Volume rendered 3D OCTA assessment of macular ischemia in patients with type 1 diabetes and without diabetic retinopathy

The aim of this study was to measure macular perfusion in patients with type 1 diabetes and no signs of diabetic retinopathy (DR) using volume rendered three-dimensional (3D) optical coherence tomography angiography (OCTA). We collected data from 35 patients with diabetes and no DR who had OCTA obtained. An additional control group of 35 eyes from 35 healthy subjects was included for comparison. OCTA volume data were processed with a previously presented algorithm in order to obtain the 3D vascular volume and 3D perfusion density. In order to weigh the contribution of different plexuses’ impairment to volume rendered vascular perfusion, OCTA en face images were binarized in order to obtain two-dimensional (2D) perfusion density metrics. Mean ± SD age was 27.2 ± 10.2 years [range 19–64 years] in the diabetic group and 31.0 ± 11.4 years [range 19–61 years] in the control group (p = 0.145). The 3D vascular volume was 0.27 ± 0.05 mm3 in the diabetic group and 0.29 ± 0.04 mm3 in the control group (p = 0.020). The 3D perfusion density was 9.3 ± 1.6% and 10.3 ± 1.6% in diabetic patients and controls, respectively (p = 0.005). Using a 2D visualization, the perfusion density was lower in diabetic patients, but only at the deep vascular complex (DVC) level (38.9 ± 3.7% in diabetes and 41.0 ± 3.1% in controls, p = 0.001), while no differences were detected at the superficial capillary plexus (SCP) level (34.4 ± 3.1% and 34.3 ± 3.8% in the diabetic and healthy subjects, respectively, p = 0.899). In conclusion, eyes without signs of DR of patients with diabetes have a reduced volume rendered macular perfusion compared to control healthy eyes.

A Processing Pipeline for Quantifying Lenticulostriate Artery Vascular Volume in Subcortical Nuclei

Lenticulostriate arteries (LSAs) supply blood to the basal ganglia region. Its lesion causes lacunar stroke and resulting neurological syndromes. However, due to its small caliber and large individual variance, the evaluation of LSAs was limited to descriptive and objective measurements. In this study, we aimed to develop a post-processing method to quantify LSAs in subcortical regions and compare their vascular volume to conventional LSA measurements. A processing pipeline was designed to extract subcortical areas in individual spaces while screening out vessels. The vascular volume of LSAs in the subcortical region was calculated from time-of-flight-magnetic resonance angiography (TOF-MRA) at 7 Tesla. The reproducibility was tested to be good for the vascular volume (n = 5, ICCA = 0.84). Comparing the results to conventional measurements, the vascular volume was significantly correlated with the number of branches (r = 0.402, p &lt; 0.001) and the length (r = 0.246, p = 0.032) of LSAs. By applying the method to a group of healthy volunteers (n = 40), we found that most LSAs crossing through the putamen which thereby has the highest vascular density among subcortical nuclei. In general, we proposed a semi-automated processing pipeline for quantifying the vascular volume of LSAs in subcortical regions. The novel method was tested to be robust and provided reasonable results. This method revealed spatial relationships among the perforating arteries and basal ganglia. The vascular volume can be used to evaluated blood supply of subcortical regions, benefiting the radiologic evaluation of neurodegenerative diseases caused by small vascular lesions.

Low-Intensity Intradialytic Exercise Attenuates the Relative Blood Volume Drop Due to Intravascular Volume Loss during Hemodiafiltration

<b><i>Introduction:</i></b> Patients in hemodiafiltration (HDF) eliminate volume overload by ultrafiltration. Vascular volume loss is among the main mechanisms contributing to adverse events such as intradialytic hypotension. Here, we hypothesize that the intradialytic exercise (IDEX) is an intervention that could improve the acute response of physiological mechanisms involved during vascular volume loss. To test this hypothesis, we evaluated the hemodynamic response to mild aerobic exercise during HDF. <b><i>Methods:</i></b> Nineteen end-stage renal disease (ESRD) patients (11 women: 40 ± 10.8 years old, and 8 men: 42 ± 21 years old) receiving HDF thrice a week, with 6 months of previous physical conditioning, participated in this study. Three HDF sessions were scheduled for each patient: 1 resting in supine position, 1 resting in sitting position, and 1 doing aerobic exercise. The first 2 sessions were taken as control. The ultrafiltration rate was set to 800 mL/h in each session. The hemodynamic response was monitored through the relative blood volume (RBV), and cardiovascular variables measured noninvasively by photoplethysmography. Adequacy variables such as Kt/V and percentage reduction of urate, urea, creatinine (Cr), and phosphate were also monitored. <b><i>Findings:</i></b> The decrease rate of the RBV was smaller in the session with IDEX compared to the sessions with no exercise. No differences were found neither in the cardiovascular variables nor in the adequacy variables among the 3 sessions. There were no hypotension events during the session with exercise, and 8 events during the sessions without exercise (<i>p</i> = 0.002). <b><i>Discussion:</i></b> Mild exercise during HDF decreased the RBV drop and was associated with less hypotension events. The lack of differences in the hemodynamic variables suggests an adequate acute response of cardiovascular compensation variables to intradialytic hypovolemia.

Neurosurgery in paediatric strokes

Paediatric strokes are a different entity owing to the difference in pathological entity causing the stroke as well as difficulty in treatment and management due to the presence of a growing brain and small vascular volume making surgery and endovascular intervention dangerous. Yet, the high neuronal plasticity coupled with unique surgical and endovascular procedures makes surgery in these conditions rewarding with improving morbidity and mortality statistics. The field is young and dynamic leading to constant change and updating. We attempt to review the current recommendations with our own experience in paediatric neurosurgery for paediatric strokes and present an overview of common conditions causing paediatric strokes. A brief review of the literature is also supplied for reference.