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A critical need exists for early, accurate diagnosis of burn wound severity to help identify the course of treatment and outcome of the wound. Laser speckle imaging (LSI) is a promising blood perfusion imaging approach, but it does not account for changes in tissue optical properties that can occur with burn wounds, which are highly dynamic environments. Here, we studied optical property dynamics following burn injury and debridement and the associated impact on interpretation of LSI measurements of skin perfusion. We used spatial frequency domain imaging (SFDI) measurements of tissue optical properties to study the impact of burn-induced changes in these properties on LSI measurements. An established preclinical porcine model of burn injury was used (n = 8). SFDI and LSI data were collected from burn wounds of varying severity. SFDI measurements demonstrate that optical properties change in response to burn injury in a porcine model. We then apply theoretical modeling to demonstrate that the measured range of optical property changes can affect the interpretation of LSI measurements of blood flow, but this effect is minimal for most of the measured data. Collectively, our results indicate that, even with a dynamic burn wound environment, blood-flow measurements with LSI can serve as an appropriate strategy for accurate assessment of burn severity.

OBJECTIVE Currently available ventricular assist devices provide continuous flow and do not adapt to the changing needs of patients. Physiological control algorithms have been proposed that adapt the pump speed based on the left ventricular pressure. However, so far, no clinically used pump can acquire this pressure. Therefore, for the validation of physiological control concepts in vivo, a system that can continuously and accurately provide the left ventricular pressure signal is needed. METHODS We demonstrate the integration of two pressure sensors into a tapered inflow cannula compatible with the HeartMate 3 (HM3) ventricular assist device. Selective laser melting was used to incorporate functional elements with a small footprint and therefore retain the geometry, function and implantability of the original cannula. The system was tested on a hybrid mock circulation system. Static and simulated physiological flow and pressure profiles were used to evaluate the combined pressure and flow sensing capabilities of the modified cannula. CONCLUSION The cannula prototypes enabled continuous pressure measurements at two points of their inner wall in the range of 100 and 200 mmHg. The developed, Bernoulli-based, two sensor model improved the accuracy of the measured simulated left ventricular pressure by eliminating the influence of flow inside the cannula. This method reduced the flow induced pressure uncertainty from up to 7.6 mmHg in single sensor measurements to 0.3 mmHg. Additionally, the two-sensor system and model enable the measurement of the blood flow through the pump with an accuracy of 0.140.04 L/min, without dedicated flow sensors.

A man in his 80s undergoing chronic hemodialysis presented with a high fever. A 10-cm soft mass was palpable in his right buttock. Abdominal computed tomography and angiography showed an incomplete-type unilateral persistent sciatic artery aneurysm (PSAA) with gas patterns and a blood flow through the aneurysm. Incision drainage was performed after arterial embolization. Gram staining of the hematoma showed gram-positive cocci that had formed chains, thus leading to a diagnosis of an infected PSAA. Drainage by incision after arterial embolization was used as the therapeutic method of choice for a massive infected PSAA with a sustained blood flow in order to prevent sciatic nerve injury and bleeding associated with PSAA resection.

Background Coronary vascular function of a chronic coronary total occlusion (CTO) immediately after recanalization is known to be poor and to be partially improved by pre-treatment with loading dose of ticagrelor vs. clopidogrel . It is unknown if this vascular dysfunction is maintained at long-term follow-up and may be improved by 1-year dual antiplatelet therapy (DAPT). Methods The TIGER is a prospective, open-label, two parallel-group controlled clinical trial , which 1:1 randomized 50 CTO patients to pre-PCI loading dose and subsequent 1-year DAPT with ticagrelor vs. clopidogrel. Coronary blood flow (CBF) under stepwise adenosine infusion was assessed after drug loading dose and at follow-up and compared between the two drug groups, adjusting for time of follow-up. Results Out of 50 patients with index CBF evaluation, 38 (76%) patients underwent angiographic follow-up (23 and 15 at 1 and 3-year, respectively) and Doppler data was available in 35 (70%). A high CBF area under the curve (AUC), already observed after loading dose in ticagrelor vs. clopidogrel group (p = 0.027), was maintained at follow-up (AUC 34815.22 ± 24,206.06 vs. AUC 22712.47 ± 13,768.95; p = 0.071). Specifically, whereas high ticagrelor loading dose-related CBF was sustained at follow-up (p = 0.933), clopidogrel loading dose-related CBF increased at follow-up (p = 0.039). Conclusion The TIGER trial showed that DAPT with ticagrelor maintained a non-significantly higher CBF in a recanalized CTO as compared to clopidogrel, whose treated patients exhibit a lower CBF immediately after PCI with a significant increase at follow-up. The clinical value of such sustained high coronary flow should be evaluated in a larger group of patients. Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT02211066 (ClinicalTrials.gov number NCT02211066 ).

Aim Coronary plaque rupture is the main cause of acute coronary syndrome (ACS), but the role of blood flow features around plaque rupture for ACS is still unknown. The present study aimed to assess the relationship between the geometric configuration of ruptured plaque and ACS occurrence using computational fluid dynamics (CFD) by moving particle method in patients with coronary artery disease. Methods In this study, 45 patients with coronary artery disease who underwent three-dimensional intravascular ultrasound (IVUS) and had a coronary ruptured plaque (24 plaques with provoked ACS, 21 without) were included. To compare the difference in blood flow profile around ruptured plaque between the patients with and without ACS, the IVUS images were analyzed via the novel CFD analysis. Results There were no significant differences in localized flow profile around ruptured plaque between the two groups when the initial particle velocity was 10.0 cm/s corresponded to a higher coronary flow velocity at ventricular diastole. However, when it was 1.0 cm/s corresponded to lower coronary flow velocity at ventricular systole, particles with lower velocity (0 ≤ V ≤ 5 cm/s) were more prevalent around ACS-PR (p=0.035), whereas particles with higher velocity (10 ≤ V ≤ 20 cm/s) were more often detected in silent plaque ruptures (p=0.018). Conclusions Three-dimensional IVUS revealed that coronary plaque rupture was a complex one with a wide variety of its stereoscopic configuration, leading to various patterns of the local coronary flow profile. A novel CFD analysis suggested that the local flow was more stagnant around ACS-provoked ruptures than in silent ones.

Background: We describe a simple and novel technique for cerebral protection during left subclavian artery (SA) stenting by inflation of a balloon-guiding catheter inside the aortic arch at the SA origin. Methods: A total of 12 patients with left SA stenosis underwent SA stenting with inflation of a balloon-guiding catheter inside the aortic arch at the left SA origin between January 2020 and December 2020. The SA stenting procedures under proximal protection were retrospectively reviewed to assess ischemic complications, hyperintense spots on diffusion-weighted imaging (DWI), and flow direction of left vertebral artery (VA) during balloon-guiding catheter inflation using ultrasonography (US). Results: The success rate of the SA stenting procedure was 100% with no symptomatic ischemic complications. None of the 12 patients showed small hyperintense spots in DWI. In all patients, the left VA on US during balloon inflation showed retrograde blood flow. Conclusions: The left VA on US had retrograde blood flow during inflation of the balloon-guiding catheter inside the aortic arch at the SA origin. Therefore, the proximal balloon protection inside the aortic arch at the SA origin is a simple and maybe a safe technique for cerebral protection during SA stenting.

Background Pseudo-spiral Cartesian sampling with compressed sensing reconstruction has facilitated highly accelerated 4D flow magnetic resonance imaging (MRI) in various cardiovascular structures. However, unlike echo planar imaging (EPI)-accelerated 4D flow MRI, it has not been validated in whole-heart applications. Hypothesis Pseudo-spiral 4D flow MRI (PROUD [PROspective Undersampling in multiple Dimensions]) is comparable to EPI in robustness of valvular flow measurements and remains comparable as the undersampling factor is increased and scan time reduced. Study Type Prospective. Population Twelve healthy subjects and eight patients with valvular regurgitation. Field Strength/Sequence 3.0 T; PROUD and EPI 4D flow sequences, 2D flow and balanced steady-state free precession sequences. Assessment Valvular blood flow was quantified using valve tracking. PROUD- and EPI-based measurements of aortic (AV) and pulmonary (PV) flow volumes and left and right ventricular stroke volumes were tested for agreement with 2D MRI-based measurements. PROUD reconstructions with undersampling factors (R) of 9, 14, 28, and 56 were tested for intervalve consistency (per valve, compared to the other valves) and preservation of peak velocities and E/A ratios. Statistical Tests We used repeated measures ANOVA, Bland-Altman, Wilcoxon signed rank, and intraclass correlation coefficients. P < 0.05 was considered statistically significant. Results PROUD and EPI intervalve consistencies were not significantly different both in healthy subjects (valve-averaged mean difference [limits of agreement width]: 3.2 +/- 0.8 [8.7 +/- 1.1] mL/beat for PROUD, 5.5 +/- 2.9 [13.7 +/- 2.3] mL/beat for EPI, P = 0.07) and in patients with valvular regurgitation (2.3 +/- 1.2 [15.3 +/- 5.9] mL/beat for PROUD, 0.6 +/- 0.6 [19.3 +/- 2.9] mL/beat for EPI, P = 0.47). Agreement between EPI and PROUD was higher than between 4D flow (EPI or PROUD) and 2D MRI for forward flow, stroke volumes, and regurgitant volumes. Up to R = 28 in healthy subjects and R = 14 in patients with valvular regurgitation, PROUD intervalve consistency remained comparable to that of EPI. Peak velocities and E/A ratios were preserved up to R = 9. Conclusion PROUD is comparable to EPI in terms of intervalve consistency and may be used with higher undersampling factors to shorten scan times further. Level of Evidence 1 Technical Efficacy Stage 2

Objective: Carotid Doppler ultrasound has been a topic of recent interest, as it may be a promising noninvasive hemodynamic monitoring tool. In this study, the relation between carotid artery blood flow and invasive cardiac output (CO) was evaluated. Design: A prospective, observational study. Setting: A single-institution, tertiary referral hospital. Participants: Eighteen elective cardiac surgery patients. Interventions: CO was measured by calibrated pulse contour analysis. Simultaneously, carotid artery pulsed-wave Doppler measurements were obtained in the operating room in three clinical settings: after induction of anesthesia (T1), after a passive leg raise maneuverer (T2), and at the end of surgery (T3). Measurements and Main Results: Correlation and trending between carotid artery blood flow and invasive CO were evaluated. Furthermore, two Bland-Altman plots were constructed to evaluate the level of agreement between carotid artery-derived CO and invasive CO measurements. Carotid artery blood flow correlated moderately with invasive CO (ρ = 0.67, 95% confidence interval 0.56-0.76, p < 0.05). Concordance between the percentage change of carotid artery blood flow and invasive CO from T1 to T3 was 72%. The level of agreement between carotid artery-derived CO and invasive CO was ±2.29; ±2.57 L/min, with a bias of 0.1; –0.54 L/min, and mean error of 50% and 48%, for the two Bland-Altman analyses, respectively. Intraexamination precision was acceptable. Conclusions: In cardiac surgery patients, carotid artery blood flow correlated moderately with invasive CO measurements. However, the trending ability of carotid artery blood flow was poor, and carotid artery-derived CO tended not to be interchangeable with invasive CO.

Introduction Intestinal blood flow evaluation during strangulated bowel obstruction is often based on the subjective assessment of the operator. Therefore, we aimed to comprehensively determine the presence or absence of intestinal blood flow based on normal light and indocyanine green (ICG) fluorescence imaging. Moreover, we ascertained whether the chosen surgical plan was appropriate, based on the patients' postoperative course and pathological findings. Methods All 14 patients diagnosed with strangulated bowel obstruction at our hospital who underwent laparoscopic surgery between July 2019 and January 2021 were enrolled. Surgical plans were chosen based on normal light imaging combined with near-infrared imaging after intravenous ICG injection. Intestinal resection was performed via a small laparotomy if resection was considered necessary. In the intestinal resection group, the presence of intestinal necrosis was examined based on the pathological findings of the resected specimens. In the intestinal preservation group, postoperative complications, such as delayed intestinal perforation and intestinal stricture, were examined. Results Intestinal resection was performed in 4 cases. The pathological findings of the resected specimens showed necrosis of the small intestine in all cases. No intra-abdominal complication occurred any of the cases, and the median postoperative hospital stay was 9.9 days. Conclusions The selection of a surgical plan in conjunction with ICG fluorescence findings was valid in all 14 cases. ICG fluorescence imaging is useful in laparoscopic surgery for strangulated bowel obstruction and may be a novel method for evaluating intestinal blood flow during surgery.

Background Many new tools for abdominal aortic aneurysm (AAA) rupture risk evaluation have been developed. These new tools need detailed hemodynamic information in AAA. However, hemodynamic data obtained from in vivo research are lacking. Thus, the objective of this study was to analyze blood flow patterns in an in vivo AAA model to acquire real-time hemodynamic information using AneurysmFlow, a novel flow evaluation system. Methods Digital subtraction angiography images of patients who underwent endovascular aneurysm repair were analyzed using the visualization function of the AneurysmFlow to classify blood flow patterns as laminar or turbulent flow. The presence of boundary layer separation was also evaluated. The time taken for contrast medium to travel from the infrarenal aortic neck to aortic bifurcation was acquired to calculate the flow velocity. Associations between characteristics of aneurysm including lumen occupying ratio of intraluminal thrombus (ILT) and the hemodynamic flow pattern were evaluated. Results A total of 37 AAA patients was enrolled. Their blood flow patterns were evaluated using the AneurysmFlow. Logistic regression analyses with lumen occupying ratio of ILT as an independent variable showed that the larger the lumen occupying ratio of ILT, the more likely the aneurysm was to show a laminar pattern (P = 0.03) and the more likely the boundary layer separation would not exist (P = 0.04). The flow velocity from the infrarenal aortic neck to the aortic bifurcation showed a positive association with the lumen occupying ratio of the ILT in linear regression analysis (P Conclusion Hemodynamic analysis of AAA with the AneurysmFlow using real-time individual patient models showed different flow patterns and flow velocities depending on ILT. This novel analytic approach using AneurysmFlow has potential to play an important role in obtaining clinically meaningful hemodynamic information of AAA.

Instructed use of reappraisal to regulate stress in the laboratory is typically associated with a more adaptive cardiovascular response to stress, indexed by either (a) lower cardiovascular reactivity (CVR; e.g., lower blood pressure) or (b) a challenge-oriented response profile (i.e., greater cardiac output paired with lower total peripheral resistance). In contrast, instructed use of suppression is associated with exaggerated CVR (e.g., greater heart rate, blood pressure). Despite this, few studies have examined if the habitual use of these strategies are related to cardiovascular responding during stress. The current study examined the relationship between cardiovascular responses to acute stress and individual differences in emotion regulation style: trait reappraisal, suppression, and emotion regulation difficulties. Forty-eight participants (25 women, 23 men) completed a standardized laboratory stress paradigm incorporating a 20-minute acclimatization period, a 10-minute baseline, and two 5-minute speech tasks separated by a 10-minute intertask rest period. The emotional valence of the speech task was examined as a potential moderating factor; participants spoke about a block of negative-emotion words and a block of neutral-emotion words. Cardiovascular parameters were measured using the Finometer Pro. Greater habitual use of suppression was associated with exaggerated blood pressure responding to both tasks. However, only in response to the negative-emotion task was greater use of reappraisal associated with a challenge-oriented cardiovascular response. The findings suggest that individual differences in emotion regulation translate to differing patterns of CVR to stress, but the emotional valence of the stressor may play a role. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Item does not contain fulltext BACKGROUND: Coronary blood flow in humans is known to be predominantly diastolic. Small studies in animals and humans suggest that this is less pronounced or even reversed in the right coronary artery (RCA). AIMS: This study aimed to characterise the phasic patterns of coronary flow in the left versus right coronary arteries of patients undergoing invasive physiological assessment. METHODS: We analysed data from the Iberian-Dutch-English Collaborators (IDEAL) study. A total of 482 simultaneous pressure and flow measurements from 301 patients were included in our analysis. RESULTS: On average, coronary flow was higher in diastole both at rest and during hyperaemia in both the RCA and LCA (mean diastolic-to-systolic velocity ratio [DSVR] was, respectively, 1.85±0.70, 1.76±0.58, 1.53±0.34 and 1.58±0.43 for LCA(rest), LCA(hyp), RCA(rest) and RCA(hyp), p

Study Objective To quantitatively evaluate the blood flow in ovaries (ischemic ovaries) that underwent torsion using indocyanine green angiography (ICGA) and assess the use of ICGA as an indicator for functional preservation of the ovaries. Design In vivo animal study. Setting The University of Yamanashi Animal Experimentation Center. Subjects Eighteen female Wistar albino rats. Interventions As an alternative to ovarian torsion, we occluded an ovary in each rat for 24 hours, after which we performed ICGA before and after releasing ischemia and extracted the following 8 parameters: Fmax (maximum F value before releasing ischemia); Tmax (time taken from the onset of an increase in F to reaching Fmax); T½max (time taken from the onset of an increase in F to reaching half of Fmax); slope (Fmax/Tmax); time ratio (T½max/Tmax); F′max (maximum F value after releasing ischemia); reperfusion rate (F′max/Fmax); and reperfusion gap (F′max – Fmax). Four weeks later, we counted the total number of primordial and primary follicles and classified the rats into functional and nonfunctional groups. Measurements and Main Results On the basis of the total number of primordial and primary follicles, 13 rats had “functional” ovaries on the clamped side, and 5 rats had “nonfunctional” ovaries. The area under the curve values for each parameter were as follows: Fmax, 0.908; Tmax, 0.569; T½max, 0.546; time ratio, 0.746; slope, 0.877; F′max, 0.723; reperfusion rate, 0.938; and reperfusion gap, 0.862. Conclusion ICGA can be used to quantitatively evaluate ovaries that have been subjected to ischemia, and the magnitude of fluorescence intensity can be an excellent predictor of ovarian necrosis. Quantifying the degree of reperfusion immediately after the release of ischemia can be an equally excellent predictor of necrosis.

It is well-established that adipose tissue accumulation is associated with insulin resistance through multiple mechanisms. One major metabolic link is the classical Randle cycle: enhanced release of free fatty acids (FFA) from hydrolysis of adipose tissue triglycerides impedes insulin-mediated glucose uptake in muscle tissues. Less well studied are the different routes of this communication. First, white adipose tissue depots may be regionally distant from muscle (i.e., gluteal fat and diaphragm muscle) or contiguous to muscle but separated by a fascia (Scarpa’s fascia in the abdomen, fascia lata in the thigh). In this case, released FFA outflow through the venous drainage and merge into arterial plasma to be transported to muscle tissues. Next, cytosolic triglycerides can directly, i.e., within the cell, provide FFA to myocytes (but also pancreatic ß-cells, renal tubular cells, etc.). Finally, adipocyte layers or lumps may be adjacent to, but not anatomically segregated, from muscle, as is typically the case for epicardial fat and cardiomyocytes. As regulation of these three main delivery paths is different, their separate contribution to substrate competition at the whole-body level is uncertain. Another important link between fat and muscle is vascular. In the resting state, blood flow is generally higher in adipose tissue than in muscle. In the insulinized state, fat blood flow is directly related to whole-body insulin resistance whereas muscle blood flow is not; consequently, fractional (i.e., flow-adjusted) glucose uptake is stimulated in muscle but not fat. Thus, reduced blood supply is a major factor for the impairment of in vivo insulin-mediated glucose uptake in both subcutaneous and visceral fat. In contrast, the insulin resistance of glucose uptake in resting skeletal muscle is predominantly a cellular defect.

C-Reactive protein and erythrocyte sedimentation rate are crucial parameters used to monitor giant cell arteritis (GCA). Given that tocilizumab is approved for the treatment of GCA, these parameters are less sensitive because of the effects of interleukin-6 receptor blockade. Thus, the optimal method for monitoring GCA patients undergoing tocilizumab therapy, especially patients exhibiting a persistent thickened vessel wall in large vessels, remains unclear. Contrast-enhanced ultrasonography (CEUS) can increase the visibility of tissue perfusion by slow blood flow, which cannot be detected by power color doppler. We used CEUS to investigate patients with active and inactive GCA of the large vessels (active large vessel arteritis [aLVV]/inactive large vessel arteritis [iLVV]) who were not administered tocilizumab in this proof-of-concept study. After injection of the ultrasound contrast agent, the contrasted area (CA) of large vessels in a transverse section was calculated twice: first when the lumen was contrasted completely and once again 4–8 s later. We investigated the value of increase in CA that exhibited the best sensitivity and specificity for aLVV. Twenty-four patients were included in this study: 15 with aLVV and 9 with iLVV. The CA increased from 32.2 ± 16.8 to 52.5 ± 21.3 mm2 (p

PURPOSE The purpose of the current study was to clarify the blood flow pattern in the left atrium (LA), potentially causing the formation of thrombosis after left upper lobectomy (LUL). The blood flow in the LA was evaluated and compared between LUL patients with and without thrombosis. For the evaluation, we applied highly accelerated 4D flow MRI with dual-velocity encoding (VENC) scheme, which was expected to be able to capture slow flow components in the LA accurately. METHODS Eight volunteers and 18 patients subjected to LUL underwent dual-VENC 4D Flow MRI. Eight patients had a history of thrombosis. We measured the blood flow velocity and stasis ratio (proportion in the volume that did not exceed 10 cm/s in any cardiac phase) in the LA and left superior pulmonary vein (LSPV) stump. For visual assessment, the presence of each collision of the blood flow from pulmonary veins and vortex flow in the LA were evaluated. Each acquired value was compared between healthy participants and LUL patients, and in LUL patients with and without thrombosis. RESULTS In LUL patients, blood flow velocity near the inflow part of the left superior pulmonary vein (Lt Upp) and mean velocity in the LA were lower, and stasis ratio in the LA was higher compared with healthy volunteers (Lt Upp 9.10 ± 3.09 vs.13.23 ± 14.19 cm/s, mean velocity in the LA 9.81 ± 2.49 vs. 11.40 ± 1.15 cm/s, and stasis ratio 25.28 ± 18.64 vs. 4.71 ± 3.03%, P = 0.008, 0.037, and < 0.001). There was no significant difference in any quantification values between LUL patients with and without thrombosis. For visual assessment, the thrombus formation was associated with no collision pattern (62.5% vs. 10%, P = 0.019) and not with vortex flow pattern (50% vs. 30%, P = 0.751). CONCLUSION The net blood flow velocity was not associated with the thrombus formation. In contrast, a specific blood flow pattern, the absence of blood flow collision from pulmonary veins, correlates to the thrombus formation in the LA.

INTRODUCTION This study aimed to investigate the effects of the strong occlusal force on the hemodynamics of gingival microcirculation. METHODS Eleven adult volunteers with healthy periodontium and normal occlusion participated in this study. Using a noncontact laser Doppler flowmeter placed at the attached gingiva and the interdental papilla of the maxillary first premolar, changes in gingival blood flow (GBF) were examined during and after clenching. RESULTS When the strong occlusal pressure was applied on the maxillary first premolar by clenching, GBF in the attached gingiva on the buccal side decreased significantly compared with the resting GBF, with medians of 2.3 mL/min/100 g and 5.4 mL/min/100 g, respectively (P

Background Impact on blood flow by double vein anastomosis in head and neck free flaps is unclear. We aimed to assess venous doppler loss of signal (LOS) rates of double vein system compared with a single vein system. Methods Consecutive free flaps with implanted venous flow couplers between 2015–2017 were included. LOS rates were compared between groups and with regard to flap type, defect site and recipient vein within double vein group. Results 92 double-vein (184 veins) and 48 single-vein flaps were included. LOS was similar in single- and double-vein flaps (11/48 (25%) versus 46/184 (25%), p = 0.765). Double veins had fewer flap takebacks compared with single vein (4.3% vs. 12.5%, p = 0.075). Common facial vein (CFV) anastomosis showed superior LOS rates compared with external jugular and CFV branches (p = 0.026). Conclusions Double vein anastomosis does not impact LOS rates, results in fewer flap takebacks, yet LOS rates depend on selected recipient vein.

The brain's vascular network dynamically affects its development and core functions. It rapidly responds to abnormal conditions by adjusting properties of the network, aiding stabilization and regulation of brain activities. Tracking prominent arterial changes has clear clinical and surgical advantages. However, the arterial network functions as a system; thus, local changes may imply global compensatory effects that could impact the dynamic progression of a disease. We developed automated personalized system-level analysis methods of the compensatory arterial changes and mean blood flow behavior from a patient's clinical images. By applying our approach to data from a patient with aggressive brain cancer compared with healthy individuals, we found unique spatiotemporal patterns of the arterial network that could assist in predicting the evolution of glioblastoma over time. Our personalized approach provides a valuable analysis tool that could augment current clinical assessments of the progression of glioblastoma and other neurological disorders affecting the brain.

Purpose Stellate ganglion block (SGB) is effective in treating head and neck pain and neuropathic diseases by increasing tissue blood flow through its sympatholytic effect. This study aimed to investigate the relationship between duration of cervical sympathetic nerve block by SGB and its therapeutic efficacy against trigeminal neuropathy after orthognathic surgery. Methods Twenty-eight patients with trigeminal neuropathy were randomly assigned to two groups (mepivacaine and levobupivacaine) according to the drug used for SGB. Increased blood flow, which is a symptom of sympathetic blockade, was recorded for 180 min after SGB. Current perception threshold, warm or cool detection threshold, and tactile detection threshold were measured preoperatively, postoperatively, on day 10 after initiation of SGB, and 3 months postoperatively to compare therapeutic efficacy between the groups. Results The levobupivacaine group had a significantly longer duration of increased blood flow compared with the mepivacaine group. Values of current perception threshold, warm and cool detection threshold, and tactile detection threshold significantly improved in the levobupivacaine group on day 10 after initiation of SGB and 3 months postoperatively. Conclusion A prolonged increase in blood flow due to long-term sympatholytic effects accelerates the therapeutic efficacy of SGB in trigeminal neuropathy.

Superb microvascular imaging (SMI) is a new Doppler method that enables the visualization of low-velocity blood flow. The aim of the study described here was to clarify whether SMI can detect prenatal pathological findings in pathologic placentas. In this prospective diagnostic observational study, pregnant women who were admitted to our center for perinatal management were enrolled. Ultrasound examinations to identify placental pathologies using SMI were performed before delivery. After delivery, the placental tissue was clipped for microscopic examination at locations determined under ultrasound guidance. The accuracy of prenatal ultrasound detection of placental pathologies was compared between women who were admitted because of fetal growth restriction (FGR), pre-eclampsia and other indications. The highest accuracy was observed with placental infarction in FGR (positive predictive value = 100%, sensitivity = 89%, area under the curve = 0.945). As a result, it became clear that SMI can accurately detect placental pathologic findings, such as placental infarction and avascular villi. This modality may improve perinatal management in cases of placental dysfunction.

Background Contrast-enhanced harmonic endoscopic ultrasound (CEH-EUS) can be used for the differential diagnosis of pancreatic lesions by evaluating microvascular circulation and patterns of contrast enhancement. However, routine use of CEH-EUS is limited by its high cost, the lack of contrast agent availability and the absence of expertise with this technique. Directional eFLOW (D-eFLOW) (Aloka Co., Ltd., Tokyo, Japan) was introduced as a new high-definition modality that detects blood flow in microvessels. Because it uses built-in functions, it entails no additional cost and reduces time for examination. The present study compared the usefulness of D-eFLOW and CEH-EUS for differential diagnosis of pancreatic and peripancreatic lesions. Methods This retrospective study analyzed 130 patients who underwent EUS and D-eFLOW examinations from January 2016 to March 2020 to evaluate pancreatic and peripancreatic masses. Results All 130 patients underwent D-eFLOW and CEH-EUS examinations. Histological diagnoses were confirmed in 130 patients by EUS-FNA and/or surgery. D-eFLOW and CEH-EUS showed good correlation in evaluating the vascularity of pancreatic and peripancreatic tumors (Fisher's exact test, p Conclusions In evaluating the characteristics of tumorous lesions, vascularity detected by D-eFLOW showed good correlation with enhancement patterns of CEH-EUS. D-eFLOW can be considered a good alternative to CEH-EUS in diagnosing pancreatic and peripancreatic masses.

Arteriovenous malformation (AVM) of the brain is a congenital vascular abnormality, in which the arterial and venous blood pools are intertwined and directly connected. This dangerous disease causes a high risk of intracranial hemorrhage and disrupts brain functioning. The preferred method of AVM treating is embolization, which is the endovascular filling of abnormal AVM vessels with a special embolic agent. Despite the fact that this method is widely used in neurosurgery, in some cases its use is accompanied by perioperative AVM vessels rupture. In this regard, the aim of this work is to study the optimal scenarios for multi-stage AVM embolization from the effectiveness and safety of the procedure point of view. Mathematically, the joint movement of blood and embolic agent in the AVM body is described on the basis of a one-dimensional two-phase filtration model, which takes into account the redistribution of blood to surrounding healthy vessels. For the numerical solution of the resulting integro-differential system of equations, a monotonic modification of the CABARET scheme is used. To find optimal embolization scenarios, the optimal control problem with phase constraints arising from medicine is formulated. A modified particle swarm optimization method is used to solve this problem numerically. This technique is used to obtain optimal embolization scenarios on the basis of real patients clinical data collected during neurosurgical operations.

This study aimed to investigate the effect of low concentration ethanol in increasing flap viability by perioperative perivascular application and compared it with that of botulinum toxin type A (BTX-A).Twenty-seven Wistar albino rats weighing 300-350 g were used in this study. The subjects were randomly divided into three equal groups: group E (ethanol, n = 9), group B (BTX-A, n = 9), and group S (saline, n = 9). In rats, the dorsal multi-territory perforator flap was elevated, and the agents were injected. In postoperative 1 wk, flap viability and vascular endothelial growth factor levels were evaluated. Also, blood flow, microvascular density, and inflammation degree of both choke zones were assessed.The mean flap survival area and vascular endothelial growth factor level were significantly higher in group E than in group B and S (P0.001). Similarly, blood flow (first choke zone, P0.012, and second choke zone, P0.001) and microvascular density (first choke zone and second choke zone, P0.001) were found to be higher in Group E compared to Group B and S in the evaluation performed from both choke zones. Also, significant inflammation was detected in the ethanol group.The positive effects of BTX-A on flap viability were achieved with a low concentration of ethanol. The fact that a low concentration of ethanol increases blood flow, angiogenesis, and flap viability more than BTX-A in the first postoperative week indicates that it can be an alternative agent for perioperative use.