Postoperative disappearance of leptomeningeal enhancement around the brainstem in glioblastoma.

PURPOSE: Leptomeningeal enhancement (LME) suggests leptomeningeal dissemination (LMD) of tumor cells, which is a complication of end-stage glioblastoma, and is associated with a poor prognosis. However, magnetic resonance imaging (MRI) occasionally indicates the disappearance of peri-brainstem LME after surgical resection of glioblastoma. Since preoperative LMD may affect treatment indications, we aimed to analyze the clinical significance of preoperative LME of the brainstem in glioblastoma. METHODS: We retrospectively collected clinical and radiological data from consecutive patients with glioblastoma and preoperative LME of the brainstem, who were treated at our hospital between 2017 and 2020. RESULTS: Among 112 patients with glioblastoma, nine (8%) showed preoperative LME of the brainstem. In comparison with tumors without LME, tumor size was significantly associated with the preoperative LME of the brainstem (p = 0.016). In addition, there was a trend toward significance for a relationship between deep tumor location and preoperative LME of the brainstem (p = 0.058). Notably, among six patients who underwent surgical resection for glioblastoma with LME of the brainstem, four showed significant radiological disappearance of the LME on postoperative MRI. This suggests that the LME did not result from LMD in these cases. Moreover, these four patients lived longer than would be expected from the presence of LMD. However, this LME disappearance was not observed after biopsy or chemoradiotherapy. CONCLUSIONS: These findings suggest that preoperative LME does not necessarily indicate the presence of untreatable LMD; moreover, LME may disappear after surgical tumor resection. Thus, transient preoperative LME could be attributed to other mechanisms, including impaired venous flow due to intratumoral arteriovenous shunts, which can be resolved by reducing the tumor burden.

CSF and venous blood flow from childhood to adulthood studied by real-time phase-contrast MRI.

PURPOSE: In vivo measurements of CSF and venous flow using real-time phase-contrast (RT-PC) MRI facilitate new insights into the dynamics and physiology of both fluid systems. In clinical practice, however, use of RT-PC MRI is still limited. Because many forms of hydrocephalus manifest in infancy and childhood, it is a prerequisite to investigate normal flow parameters during this period to assess pathologies of CSF circulation. This study aims to establish reference values of CSF and venous flow in healthy subjects using RT-PC MRI and to determine their age dependency. METHODS: RT-PC MRI was performed in 44 healthy volunteers (20 females, age 5-40 years). CSF flow was quantified at the aqueduct (Aqd), cervical (C3) and lumbar (L3) spinal levels. Venous flow measurements comprised epidural veins, internal jugular veins and inferior vena cava. Parameters analyzed were peak velocity, net flow, pulsatility, and area of region of interest (ROI). STATISTICAL TESTS: linear regression, student's t-test and analysis of variance (ANOVA). RESULTS: In adults volunteers, no significant changes in flow parameters were observed. In contrast, pediatric subjects exhibited a significant age-dependent decrease of CSF net flow and pulsatility in Aqd, C3 and L3. Several venous flow parameters decreased significantly over age at C3 and changed more variably at L3. CONCLUSION: Flow parameters varies depending on anatomical location and age. We established changes of brain and spinal fluid dynamics over an age range from 5-40 years. The application of RT-PC MRI in clinical care may improve our understanding of CSF flow pathology in individual patients.

Valley Index as a Predictor of Prenatal Diagnosis of Total Anomalous Pulmonary Venous Connection.

INTRODUCTION: Total anomalous pulmonary venous connection (TAPVC) has a low prenatal diagnostic rate. Therefore, we investigated whether Doppler waveforms with a low pulsatility in the pulmonary veins can indicate fetal TAPVC. METHODS: This retrospective study included 16 fetuses with TAPVC, including 10 with complex congenital heart disease and 104 healthy fetuses that underwent fetal echocardiography. Pulmonary venous S and D wave flow velocities and the valley (representing the lowest velocity between the S and D waves) were measured. Valley indices I and II were then calculated as (velocity of valley/greater of the S and D wave velocities) and (velocity of valley/lesser of the S and D wave velocities), respectively. RESULTS: Supra/infracardiac TAPVC cases exhibited significantly greater valley indices than that of the healthy group. After adjusting for gestational age at fetal echocardiography, valley indices I (odds ratio [OR] 7.26, p < 0.01) and II (OR: 9.23, p < 0.01) were significant predictors of supra/infracardiac TAPVC. Furthermore, valley indices I and II exhibited a high area under the curve for detecting supra/infracardiac TAPVC, regardless of the presence of pulmonary venous obstruction. CONCLUSION: The valley index may be a useful tool for the detection of fetal TAPVC.

Association between intrarenal venous flow from Doppler ultrasonography and acute kidney injury in patients with sepsis in critical care: a prospective, exploratory observational study.

BACKGROUND: Intrarenal venous flow (IRVF) patterns assessed using Doppler renal ultrasonography are real-time bedside visualizations of renal vein hemodynamics. Although this technique has the potential to detect renal congestion during sepsis resuscitation, there have been few studies on this method. We aimed to examine the relationship between IRVF patterns, clinical parameters, and outcomes in critically ill adult patients with sepsis. We hypothesized that discontinuous IRVF was associated with elevated central venous pressure (CVP) and subsequent acute kidney injury (AKI) or death. METHODS: We conducted a prospective observational study in two tertiary-care hospitals, enrolling adult patients with sepsis who stayed in the intensive care unit for at least 24 h, had central venous catheters placed, and received invasive mechanical ventilation. Renal ultrasonography was performed at a single time point at the bedside after sepsis resuscitation, and IRVF patterns (discontinuous vs. continuous) were confirmed by a blinded assessor. The primary outcome was CVP obtained at the time of renal ultrasonography. We also repeatedly assessed a composite of Kidney Disease Improving Global Outcomes of Stage 3 AKI or death over the course of a week as a secondary outcome. The association of IRVF patterns with CVP was examined using Student's t-test (primary analysis) and that with composite outcomes was assessed using a generalized estimating equation analysis, to account for intra-individual correlations. A sample size of 32 was set in order to detect a 5-mmHg difference in CVP between IRVF patterns. RESULTS: Of the 38 patients who met the eligibility criteria, 22 (57.9%) showed discontinuous IRVF patterns that suggested blunted renal venous flow. IRVF patterns were not associated with CVP (discontinuous flow group: mean 9.24 cm H2O [standard deviation: 3.19], continuous flow group: 10.65 cm H2O [standard deviation: 2.53], p = 0.154). By contrast, the composite outcome incidence was significantly higher in the discontinuous IRVF pattern group (odds ratio: 9.67; 95% confidence interval: 2.13-44.03, p = 0.003). CONCLUSIONS: IRVF patterns were not associated with CVP but were associated with subsequent AKI in critically ill adult patients with sepsis. IRVF may be useful for capturing renal congestion at the bedside that is related to clinical patient outcomes.

Evaluation of extent vs velocity of cortical venous filing in stroke outcome after endovascular thrombectomy.

PURPOSE: Abnormal venous drainage may affect the prognosis of patients undergoing endovascular reperfusion therapy (ERT). Herein, time-resolved dynamic computed tomography arteriography (dCTA) was applied to evaluate the relationship between the velocity and extent of cortical venous filling (CVF), collateral status and outcomes. METHODS: Thirty-five consecutive patients with acute anterior circulation occlusion who underwent ERT within 24 h of onset and successfully recanalized were enrolled. All patients underwent dCTA before ERT. Slow first or end of CVF was considered to occur when the time point of CVF appearance or disappearance on the affected side occurred after than that on the healthy side, whereas an equal CVF, a CVF reduced by ≤ 50%, or by > 50% on the affected side, were considered good, intermediate, and poor CVF extent, respectively. RESULTS: Slow first CVF (29 patients, 82.8%), slow end of CVF (29, 85.7%), and intermediate extent of CVF (7, 20.0%) were not associated with collateral status or outcomes. Poor extent of CVF (6, 17.1%) was associated with poor collateral status, higher proportion of midline shift, larger final infarct volume, higher modified Rankin Scale (mRS) score at discharge, and higher proportion of in-hospital mortality. All patients with transtentorial herniation had poor extent of CVF, and those with poor CVF extent had an mRS score ≥ 3 at discharge. CONCLUSION: Poor CVF extent, as assessed by dCTA, is a more accurate and specific marker than slow CVF to identify patients at high risk for poor outcomes after ERT.

Umbilical Venous Volume Flow in Late-Onset Fetal Growth Restriction.

OBJECTIVES: Umbilical vein flow (UVF) is reduced in fetal growth restriction (FGR). We compared absolute and size-adjusted UVF (estimated fetal weight [EFW] and abdominal circumference [AC]) and rates of abnormal UVF parameters (<10th percentile) among FGR fetuses meeting Delphi criteria (FGR-D) against small for gestational age (SGA) fetuses and appropriate for gestational age (AGA) controls. METHODS: Absolute UVF, UVF/EFW, and UVF/AC were compared between 73 FGR pregnancies (35 FGR-D, 38 SGA) and 108 AGA controls. Rates of abnormal UVF were compared to abnormal umbilical artery pulsatility index (UAPI). Independent samples t-tests, Mann-Whitney U, odds ratio (OR), chi-squared, and Fisher's exact tests were used as appropriate. RESULTS: Mean absolute UVF was significantly decreased in FGR-D compared to AGA (P = .0147), but not between SGA and AGA fetuses. The incidence of both abnormal absolute UVF and UVF/AC values (<10th centile) was higher among late-onset FGR fetuses versus AGA fetuses (UVF: OR 2.7, confidence interval [CI] 1.37-5.4; UVF/AC: OR 2.73, CI 1.37-5.4). UVF was more frequently abnormal than UAPI and in only two fetuses were both Doppler values abnormal. CONCLUSION: Absolute UVF is altered in late-onset FGR, and most pronounced among FGR-D. UVF may provide additional insight into fetal compromise in those affected by growth restriction.

The repeatability, reproducibility, and influencing factors of intrarenal Doppler ultrasonography in dogs without heart disease.

Renal impairment is concurrent with adverse outcomes such as heart disease in humans and dogs. Intrarenal Doppler ultrasonography (IRD) is used to assess intrarenal hemodynamics, and resistance index (RI) and venous impedance index (VII) are used to evaluate intrarenal hemodynamics in humans with heart failure. However, only a few studies have assessed the efficacy of IRD, especially VII, in dogs, and the methods differ between studies. Additionally, repeatability, reproducibility, and factors influencing IRD values have not been validated in dogs. This prospective, analytical study aimed to assess repeatability and reproducibility of IRD, and to clarify influencing factors of IRD in dogs without heart disease. We enrolled 78 dogs without heart disease. The RI and VII were highly reproducible, and the reference intervals for VII were 0.13-0.37. Differences in transducer (sector and convex) and posture (right lateral and supine decubitus position) had no effect on the IRD values. In contrast, RI and VII were higher in the renal vessels than in interlobar vessels. Age affected RI values (r = 0.39, P < 0.001), but there was no correlation between age, body weight, and VII. In conclusion, IRD is a repeatable and reproducible method to assess intrarenal hemodynamics in dogs. The findings also suggest that age should be considered while interpreting RI.

Bio-Humoral and Non-Invasive Haemodynamic Correlates of Renal Venous Flow Patterns across the Heart Failure Spectrum.

Background: We evaluated the bio-humoral and non-invasive haemodynamic correlates of renal congestion evaluated by Doppler renal venous flow (RVF) across the heart failure (HF) spectrum, from asymptomatic subjects with cardiovascular risk factors (Stage A) and structural heart disease (Stage B) to patients with clinically overt HF (Stage C). Methods: Ultrasound evaluation, including echocardiography, lung ultrasound and RVF, along with blood and urine sampling, was performed in 304 patients. Results: Continuous RVF was observed in 230 patients (76%), while discontinuous RVF (dRVF) was observed in 74 (24%): 39 patients had pulsatile RVF, 18 had biphasic RVF and 17 had monophasic RVF. Stage C HF was significantly more common among patients with dRVF. Monophasic RVF was associated with worse renal function and a higher urinary albumin-to-creatinine ratio (uACR). After adjusting for hypertension, diabetes mellitus, the presence of Stage C HF and serum creatinine levels, worsening RVF patterns were associated with higher NT-proBNP levels, worse right ventricular-arterial coupling, larger inferior vena cava and higher echo-derived pulmonary artery wedge pressure. This trend was confirmed when only patients with HF Stage C were analysed after adjusting for the left ventricle ejection fraction (LVEF). Conclusion: Abnormal RVF is common across the HF spectrum. Worsening RVF patterns are independently associated with increased congestion, worse non-invasive haemodynamics and impaired RV-arterial coupling. RVF evaluation could refine prognostic stratification across the HF spectrum, irrespective of LVEF.

Portal blood flow-dependent NO-mediated lymph formation in rat jejunum.

The higher permeability of the venules in jejunal microcirculation to albumin contributes to the increased mesenteric lymph formation. Recently, we demonstrated that water intake induced serotonin release from enterochromaffin cells in rat jejunum, serotonin of which circulated through the portal vein into blood circulation and then increased the mesenteric lymph formation. The mode of action of serotonin remains unclear. Therefore, we aimed to clarify the mechanisms involved in the regulation of the jejunal lymph formation with permeant albumin in in vivo rat experiments. We investigated the effects of intravenous administration of serotonin or water intake on the jejunal-originated lymph volume and the concentration of albumin in the lymph in the presence or absence of L-NAME. The effects of intravenous administration of L-NAME, nicardipine, A23187, and ML-7 on the lymph formation with permeant albumin were also evaluated. Serotonin or water intake significantly increased the mesenteric lymph volume with permeant albumin in the jejunal microcirculation. The serotonin- and water intake-mediated responses were significantly reduced by the pretreatment with intravenous administration of L-NAME. Intravenous administration of L-NAME itself also decreased significantly the jejunal lymph formation. Administration of A23187 and ML-7 significantly reduced the jejunal lymph formation with permeant albumin. In contrast, administration of nicardipine significantly increased the lymph formation. In conclusion, portal venous blood flow- or serotonin-mediated NO release from venular endothelial cells plays physiologically key roles in the lymph formation in rat jejunum via the extrusion of calcium ions and inactivation of MLCK in endothelial cells.

Evaluation of the selected parameters of the fetal diastolic functions in normally grown or macrosomic fetuses of gestational diabetic mothers with poor glycaemic control.

OBJECTIVE: This study aimed to investigate whether the third trimester fetal cardiac diastolic function measured by selected conventional Doppler indices is affected in appropriate-for-gestational-age or macrosomic fetuses of gestational diabetic mothers with poor glycaemic control. METHODS: This cross-sectional study included 93 pregnant women divided into two groups. Group 1 included 45 appropriate-for-gestational-age or macrosomic fetuses from gestational diabetic mothers with poor glycaemic control (study group). Group 2 included 48 appropriate-for-gestational-age fetuses from gestational age-matched healthy mothers (control group). Functional fetal cardiac parameters and fetoplacental Doppler parameters were measured. Data were compared between the two groups. RESULTS: Maternal characteristics did not differ significantly between the study and the control group. There were no significant differences in the early and late velocity, early/late velocity ratio of both mitral and tricuspid valves, the fetal pulmonary vein pulsatility index, and the ductus venosus pulsatility index between the study and the control group. Moreover, the rate of abnormal Doppler findings in pulmonary vein (pulmonary vein pulsatility index >95th centile), ductus venosus (ductus venosus pulsatility index >95th centile), and peripheral vessels (umbilical artery pulsatility index >95th centile, middle cerebral artery pulsatility index <5th centile, cerebra-placental index >95th centile) were comparable in both groups. CONCLUSIONS: The third trimester fetal diastolic functions measured by selected conventional Doppler techniques do not seem to be altered in appropriate-for-gestational-age or macrosomic fetuses of gestational diabetic mothers who have poor glycaemic control.

Plantar Venous Pump Activity, Generalized Joint Hypermobility, and Foot Mobility in Ballerinas: A Case-Control Study.

CONTEXT: The plantar venous pump (PVP) is a vascular network located between the muscles of the foot arch. It has been suggested foot mobility is critical for PVP activation. OBJECTIVE: This study investigates the effect of generalized joint hypermobility (GJH) on foot mobility and PVP activity in ballerinas and to determine how a short-term warm-up exercise impacts these parameters in the presence of GJH. DESIGN: Prospective study. METHODS: Twelve ballerinas (age = 16.73 [1.8] y) and 15 non-dancer-matched controls (age = 16.31 [2.1] y) were included. When performing weight-bearing activities, venous return parameters (diameter, velocity, and flow volume) from the posterior tibial vein were measured using color and spectral Doppler ultrasonography. Foot mobility was determined using navicular drop test. The participants performed a 10-minute cycling exercise to reveal its effect on reducing tissue stiffness. All measurements were performed synchronously and twice-before and after the cycling exercise. RESULTS: The results showed the navicular height obtained before and after exercise in the ballerinas was significantly different compared with that obtained in the sitting position, and the values obtained in the 3 measurement positions in the nondancer group were significantly different from each other (P < .05). The difference between the venous diameter values measured before and after exercise and the reference value was significant in both groups (P < .001). There was a significant decrease in venous velocity following exercise in the nondancer group (P = .044). The venous volume values obtained after exercise were significantly different between the groups (P = .039). CONCLUSIONS: The GJH has no distinctive effect on foot mobility and PVP activity in ballerinas. The presence of GJH did not influence the effect of short-term warm-up exercise on foot mobility and PVP activity. We believe that measuring the navicular drop and venous return with a more precise synchronization may provide additional information regarding the link between arch tension and venous return.

Intraoperative Assessment of Hepatic Vein Tracings in Constrictive Pericarditis During Surgical Pericardiectomy.

CONSTRICTIVE PERICARDITIS is characterized by progressive inflammation and fibrosis of the pericardium. It manifests with symptoms of heart failure. The only effective treatment is surgical pericardiectomy. The assessment and diagnosis of constrictive pericarditis with echocardiography is well described with spontaneous ventilation. However, there are limited data on constrictive pericarditis assessment with transesophageal echocardiography with positive pressure ventilation. Also, intraoperative hepatic venous Doppler flow mostly is used intraoperatively to assess the severity of tricuspid regurgitation by focusing on the flow reversal during systole. In this e-challenge, the authors focus on the hepatic vein Doppler tracing as a means to show improvement in diastolic function during positive pressure ventilation in a patient undergoing pericardiectomy. This case demonstrates a severely blunted diastolic flow pattern in the hepatic vein that is reversed after successful pericardiectomy. Also, it shows blunted flow during systole compared to diastole post-pericardiectomy, indicating high right atrial pressure.

Prolonged pulmonary pulse transit time is associated with symptoms in patients with significant mitral stenosis and sinus rhythm.

INTRODUCTION: Pulmonary pulse transit time (pPTT) is a novel noninvasive echocardiographic measure to assess pulmonary arterial hemodynamics. It has been shown to be shorter in precapillary pulmonary hypertension (PHT). Mitral stenosis (MS) is one of the causes of postcapillary PHT. We aimed to investigate pPTT in patients with MS and its relationship with symptoms. METHODS: We included 51 patients with MS (25 were asymptomatic, NYHA I, and 26 were symptomatic, NHYA II or III), and 50 controls, and evaluated their demographic characteristics and echocardiographic variables, including pPTT. RESULTS: Baseline characteristics, including age, sex, body mass index, and cardiovascular risk factors, were similar between the MS and the control group. The pPTT was longer in the MS group than in the control group (0.21 ± 0.08 vs 0.15 ± 0.05, P < .001). Patients with symptomatic MS had longer pPTT than asymptomatic patients (P = .005). The pPTT was positively correlated with left atrial volume index and systolic pulmonary artery pressure, and negatively with tricuspid annular plane systolic excursion (r = .432; P < .001, r = .319; P = .001, r = -.293; and P = .003, respectively). CONCLUSION: The measurement of pPTT appears clinically relevant in patients with PHT. Further studies evaluating whether it is useful in distinguishing precapillary from postcapillary PHT are required.

Abnormal venous postural control: multiple sclerosis-specific change related to gray matter pathology or age-related neurodegenerative phenomena?

BACKGROUND: Autonomic nervous system dysfunction has been previously observed in multiple sclerosis (MS) patients. OBJECTIVE: To assess associations between magnetic resonance imaging-detected neuroinflammatory and neurodegenerative pathology and postural venous flow changes indicative of autonomic nervous system function. METHODS: We used a standardized 3T magnetic resonance imaging protocol to scan 138 patients with MS and 49 healthy controls. Lesion volume and brain volumes were assessed. The cerebral venous flow (CVF) was examined by color-Doppler sonography in supine and upright positions and the difference was calculated as ΔCVF. Based on ΔCVF, subjects were split into absolute or quartile groups. Student's t test, χ2-test, and analysis of covariance adjusted for age and sex were used accordingly. Benjamini-Hochberg procedure corrected the p-values for multiple comparisons. RESULTS: No differences were found between healthy controls and patients with MS in both supine and upright Doppler-derived CVF, nor in prevalence of abnormal postural venous control. Patients with absolute negative ΔCVF had higher disability scores (p = 0.013), lower gray matter (p = 0.039) and cortical (p = 0.044) volumes. The negative ΔCVF MS group also showed numerically worse bladder/bowel function when compared to the positive ΔCVF (2.3 vs. 1.5, p = 0.052). Similarly, the lowest quartile ΔCVF MS group had higher T1-lesion volumes (p = 0.033), T2-lesion volumes (p = 0.032), and lower deep gray matter (p = 0.043) and thalamus (p = 0.033) volumes when compared to those with higher ΔCVF quartiles. CONCLUSION: No difference in postural venous outflow between patients with MS and healthy controls was found. However, when the abnormal ΔCVF is present within the MS population, it may be associated with more inflammatory and neurodegenerative pathology. Further studies should explore whether the orthostatic venous changes are an aging or an MS-related phenomenon and if the etiology is due to impaired autonomic nervous system functioning.

Does the prone sleeping position affect the intracranial dural venous flow?

PURPOSE: There are few studies documenting the effect of posture on intracranial dural venous flow. The aim of the present study was to explore alterations caused by the prone position using magnetic resonance (MR) venography. METHODS: A total of eight patients (five men and three women) underwent non-contrast MR venography in both supine and prone positions. RESULTS: In the prone position, an increase in intracranial dural venous flow was found in all patients in the non-dominant transverse and sigmoid sinuses. An increase in venous flow to the straight sinus was observed in 75% of the patients. Flow to the superior ophthalmic vein decreased in three patients. No postural flow alterations were observed in any of the patients in the superior sagittal, dominant transverse, and sigmoid sinuses. CONCLUSION: Based on results of the study, in the prone sleeping position, part of the intracranial venous flow may be preferentially drained through the straight and non-dominant transverse sinuses.

Hepatic hypertrophy and hemodynamics of portal venous flow after percutaneous transhepatic portal embolization.

BACKGROUND: Percutaneous transhepatic portal embolization (PTPE) is useful for safe major hepatectomy. This study investigated the correlation between hepatic hypertrophy and hemodynamics of portal venous flow by ultrasound sonography after PTPE. METHODS: We analyzed 58 patients with PTPE, excluding those who underwent recanalization (n = 10). Using CT volumetry results 2 weeks after PTPE, the patients were stratified into a considerable hypertrophy group (CH; n = 15) with an increase rate of remnant liver volume (IR-RLV) ≥ 40% and a minimal hypertrophy group (MH; n = 33) with an IR-RLV < 40%. We investigated the hemodynamics of portal venous flow after PTPE and the favorable factors for hepatic hypertrophy. RESULTS: Univariate and multivariate analysis identified the indocyanine green retention rate at 15 min (ICGR15) and increase rate of portal venous flow volume (IR-pFV) at the non-embolized lobe on day 3 after PTPE as independent favorable factors of IR-RLV. Patients with IR-pFV on day 3 after PTPE ≥100% and ICGR15 ≤ 15% (n = 13) exhibited significantly increased IR-RLV compared with others (n = 35). CONCLUSIONS: Cases with high IR-pFV on day 3 after PTPE exhibited better hepatic hypertrophy. Preserved liver function and increased portal venous flow on day 3 were important.

Pulmonary Vein Flow Impedance: An Early Predictor of Cardiac Dysfunction in Intrauterine Growth Restriction.

INTRODUCTION: In intrauterine growth restriction (IUGR), increased uteroplacental vascular impedance contributes to preferential flow to left ventricle (LV), with consequent alteration of its compliance and increased left atrial (LA) pressure. Pulmonary vein pulsatility index (PVPI) reflects the increased impedance to LA filling and could be used as a cardiac monitoring parameter in IUGR. MATERIAL AND METHODS: A total of 27 IUGR fetuses (group 1), 28 fetuses with appropriate growth for gestational age from hypertensive mothers (group 2), and 28 controls (group 3) were studied. Pulsatility indices (PIs) of pulmonary veins and ductus venosus were calculated by Doppler echocardiography. Obstetric ultrasound was used to assess the PIs of uterine, umbilical, and middle cerebral arteries. Statistical analysis used analysis of variance, post-hoc Tukey, and Pearson's tests. RESULTS: Mean PVPI was higher in IUGR group (1.27 ± 0.39) when compared to groups 2 (1.02 ± 0.37; p = 0.01) and 3 (0.75 ± 0.12; p < 0.001). In group 2, moderate correlation between PVPI and ductus venosus pulsatility index (DVPI) was found but not between PVPI and cerebroplacental ratio (CPR). DISCUSSION: Higher PVPI in IUGR reflects decreased LV compliance and altered LA dynamics. As LV dysfunction precedes right ventricle, our results suggest that PVPI could be an early echocardiographic parameter of fetal diastolic function in IUGR.

Femoral venous flow velocity during passive ankle exercise in patients with chronic spinal cord injury.

[Purpose] We examined the effect of passive ankle exercise on femoral venous flow in paralyzed, atrophied lower legs of patients with chronic spinal cord injury. [Participants and Methods] Ten males with complete spinal cord injury at the T6-12 levels and ten able-bodied males participated in this study. B-mode muscle ultrasound was performed on the medial gastrocnemius muscle to evaluate muscle atrophy. Doppler ultrasound was used to measure the time-averaged mean velocity in the femoral vein at rest and during passive motion of the ankle. [Results] Mean muscle thickness was significantly reduced in the spinal cord injury group, showing a mean value of 67.2% compared with able-bodied participants. No significant differences were observed in the time-averaged mean velocity at rest between the groups, although they were slightly lower in the spinal cord injury group than in the able-bodied group. During passive motion, no significant difference was observed in the time-averaged mean velocity between the groups, although the mean value in those with spinal cord injury was 65.9% that of the able-bodied group. Time-averaged mean velocity increased in both groups, compared with baseline. [Conclusion] Passive ankle exercise increased time-averaged mean velocity in spinal cord injury, but venous blood velocity was reduced in spinal cord injury compared to the able-bodied group. We believe that significant muscle atrophy affected our results in chronic spinal cord injury.

Spatial distribution of flow and oxygenation in the cerebral venous drainage system.

PURPOSE: To investigate the venous oxygenation and flow in the brain, and determine how they might change under challenged states. MATERIALS AND METHODS: Eight healthy human subjects (24-37 years) were studied. T2 -relaxation under spin tagging (TRUST) magnetic resonance imaging (MRI) and phase-contrast MRI were performed to measure venous oxygenation and venous blood flow, respectively, in the superior sagittal sinus (SSS), the straight sinus (SS), and the internal jugular veins (IJVs). Venous oxygenation was assessed at room air (0.03%CO2 , 21%O2 ) and under hyperoxia (O%CO2 , 95%O2 , and 5%N2 ) conditions. Venous blood flow was assessed at room air and under hypercapnia (5%CO2 , 21%O2 , and 74%N2 ) conditions. Whole-brain blood flow was also measured at the four feeding arteries of the brain using phase-contrast MRI. The changes in venous oxygenation and blood flow from room air to hyperoxia or hypercapnia conditions were tested using paired t-tests. RESULTS: Venous oxygenation in the SSS, the SS, and the IJVs was 61 ± 4%, 64 ± 4%, and 62 ± 4%, respectively, at room air, and increased to 70 ± 3% (P < 0.01 compared to room air), 71 ± 5% (P = 0.59), and 68 ± 5% (P < 0.05) under hyperoxic condition. The SSS, SS, and IJV drained 46 ± 9%, 16 ± 4%, and 79 ± 1% of whole-brain blood flow, respectively, and this flow distribution did not change under hypercapnic condition (P > 0.5). CONCLUSION: The results found in this study provide insight into the venous oxygenation and venous flow distribution and its heterogeneity among different venous structures. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1091-1098.

Stomach herniation prior to nonreassuring fetal status in a case of fetal gastroschisis.

The neonatal prognosis in gastroschisis is generally good; however, intrauterine fetal death (IUFD) and nonreassuring fetal status (NRFS) sometimes occur in fetal cases of gastroschisis. Previously, we reported stomach herniation as a possible risk factor for IUFD or NRFS in fetuses with gastroschisis. We report a case of fetal gastroschisis showing stomach herniation and increased velocity of the umbilical venous (UV) flow the day before NRFS by electronic fetal monitoring (EFM). A 27-year-old pregnant woman was followed up from 16 weeks' gestation due to fetal gastroschisis. At 33 + 1 weeks' gestation, EFM displayed a reassuring fetal state, while the ultrasound examination revealed fetal stomach herniation and an increased flow velocity of the UV in the abdomen. One day later, EFM displayed NRFS, and the patient underwent emergency caesarean section. This case showed stomach herniation preceding the occurrence of NRFS. Stomach herniation may be a predictor of NRFS in fetuses with gastroschisis.