Evaluation Of Blood Perfusion Research Articles

Perfusion outcomes with near-infrared indocyanine green imaging system in laparoscopic total mesorectal excision for mid-rectal or low-rectal cancer (POSTER): a study protocol

IntroductionAnastomotic leakage (AL) is defined as the failure of complete healing or disruption of the anastomosis subsequent to rectal cancer surgery, resulting in the extravasation of intestinal contents into the...

Nesfatin-1 regulates the HMGB1-TLR4-NF-κB signaling pathway to inhibit inflammation and its effects on the random skin flap survival in rats

ObjectiveRandom skin flaps are often placed by plastic surgeons to treat limb deformities and dysfunction. Nesfatin-1 (NES) is a peptide that exerts angiogenic, anti-inflammatory, and anti-oxidant effects. We assessed the impact of NES on flap survival and the underlying mechanism. MethodsWe modified the McFarlane random skin flap rat model. Thirty-six male Sprague-Dawley rats were randomly divided into a control group (corn oil solution with DMSO), low-dose group (NES-L at 10 µg/kg/day), and high-dose group (NES-H at 20 µg/kg/day). On day 7 after surgery, average flap survival areas were calculated. Laser Doppler blood flow monitoring and lead oxide/gelatin angiography were used to evaluate blood perfusion and neovascularization, respectively. Flap histopathological status was evaluated by hematoxylin and eosin (H&E) staining. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. Immunohistochemical techniques were used to evaluate the expression of angiogenetic and inflammatory factors. ResultsIn the experimental groups, the mean skin flap survival areas and blood perfusion increased considerably. The SOD activities in the experimental groups increased and the MDA contents decreased. Immunohistochemically, VEGF expression was upregulated in the experimental groups and the expression levels of inflammatory factors decreased markedly. ConclusionNES inhibited ischemic skin flap necrosis, promoted angiogenesis, and reduced ischemia-reperfusion injury and inflammation. Inhibition of the inflammatory HMGB1-TLR4-NF-κB signal pathway, which reduced flap inflammation and oxidative stress, may explain the enhanced flap survival.

CCN1 secreted by human adipose-derived stem cells enhances wound healing and promotes angiogenesis through activating the AKT signalling pathway.

The study aimed to explore the role of cellular communication network factor 1 (CCN1) an extracellular matrix protein in hADSC-treated wound healing. Immunofluorescence and enzyme-linked immunosorbent assays (ELISA) were used to demonstrate the secretion of CCN1 by hADSCs, isolated from human fat tissue. We investigated the role of CCN1 in wound healing by knockdown of CCN1 expression in hADSCs using CCN1 siRNA. Conditioned medium of hADSCs or hADSCs with CCN1 knocked down (hADSC-CMCCN1↓ ) was collected. After treatment with plain DMEM/F12, hADSC-CM, hADSC-CMCCN1↓ , or recombinant human CCN1 (rhCCN1), the wound healing abilities of human umbilical vascular endothelial cells (HUVECs) were assayed, and the AKT, also known as protein kinase B (PKB), signalling pathway was detected using western blotting. Next, we created full-thickness skin wounds on the backs of the mice and different treatments were applied to the wound surface. Wound size was measured using a digital camera on days 0-10, and evaluated. H&E and immunohistochemical staining were performed, and laser Doppler perfusion imaging was used to evaluate blood perfusion. The wound model and wound-healing assay showed that the hADSCs-CM and rhCCN1 groups had enhanced wound healing compared to the hADSCs-CMCCN1↓ group. Further, CCN1 and hADSCs-CM promoted the proliferation and migration of HUVECs through the AKT signalling pathway. We concluded that CCN1 secreted by hADSCs enhances wound healing and promotes angiogenesis by activating the AKT signalling pathway. CCN1 plays a vital role in the regulation of hADSCs-CM during wound healing.

Contrast-enhanced ultrasonography for evaluation of the blood perfusion of sciatic nerves in healthy dogs.

Blood supply to the peripheral nerves is essential for fulfilling their structural and functional requirements. This prospective, experimental, exploratory study aimed to assess the feasibility of contrast-enhanced ultrasonography (CEUS) for evaluating blood perfusion of the sciatic nerve in normal dogs. Contrast-enhanced ultrasonography examinations were performed on the bilateral sciatic nerves after bolus injection of Sonazoid™ (0.015mL/kg) in 12 healthy Beagles for 150 s. Then, qualitative assessment of the wash-in timing, degree and enhancement patterns, and quantitative measurement of the peak intensity and time to peak intensity were performed from the sciatic nerve. The results were compared to those obtained from the adductor muscle around the nerve and caudal gluteal artery. After contrast agent injection, the sciatic nerve was enhanced at approximately 13-14 s, immediately after wash-in of the caudal gluteal artery. The peak intensity of the sciatic nerve was significantly lower than that of the caudal gluteal artery and higher than that of the adductor muscle. The time to peak intensity was significantly slower than that of the caudal gluteal artery; but was not significantly different from that of the adductor muscle. There were no significant differences in the peak intensity and time to peak intensity between the left and right sciatic nerves. These results demonstrate the feasibility of CEUS to assess blood perfusion of the sciatic nerve in healthy dogs qualitatively and quantitatively. This result from healthy dogs could serve as a reference for further studies that evaluate the sciatic nerve under pathological conditions.

Evaluation of blood perfusion using laser doppler flowmetry during endoscopic lumbar sympathectomy in patients with plantar hyperhidrosis: a retrospective observational study

The purpose of this study is to evaluate whether monitoring the changes of skin blood flow may be effective in assessing blood perfusion during endoscopic lumbar sympathectomy (ELS) in patients with plantar hyperhidrosis. In this study, a total of 30 patients who underwent surgical treatment for plantar hyperhidrosis at the Department of Thoracic and Cardiovascular Surgery in Yonsei University Gangnam Severance Hospital, Seoul, Korea, between July 2020 and December 2020, were retrospectively analyzed. Sympathetic denervation was performed on the third lumbar ganglion, and intraoperative laser doppler flowmetry (LDF) was used to detect the lumbar sympathetic chain accurately. We observed an abrupt increase of peripheral blood flow after sympathetic denervation, and the median percent changes of perfusion unit were 173.27 (inter-quartile range, IQR 195.48) and 392.98 (IQR 597.27) for the left and right sympathectomies, respectively. This study demonstrated the efficacy of monitoring skin blood flow via LDF during ELS. This result suggests that exact detection of blood flow using LDF is essential for improving the accuracy of ELS by checking the perfusion site on the sole in patients with plantar hyperhidrosis.

Clinical application of expanded internal mammary artery perforator flap combined with vascular supercharge in reconstruction of faciocervical scar

Objective: To summarize the clinical experience of expanded internal mammary artery perforator (IMAP) flap combined with vascular supercharge in reconstruction of faciocervical scar. Methods: The retrospective observational study was conducted. From September 2012 to May 2021, 23 patients with postburn or posttraumatic faciocervical scars who met the inclusion criteria were admitted to Shanghai Ninth People's Hospital of Shanghai Jiao Tong University School of Medicine, including 18 males and 5 females, aged from 11 to 58 years, all of whom were reconstructed with expanded IMAP flaps. At the first stage, one or two skin and soft tissue expander (s) with appropriate rated capacity were implanted in the anterior chest area according to the location and size of the scars. The IMAP, thoracic branch of supraclavicular artery, and lateral thoracic artery were preserved during the operation. The skin and soft tissue expanders were inflated with normal saline after the operation. The flaps were transferred during the second stage. The dominant IMAP was determined preoperatively using color Doppler ultrasound (CDU) blood flow detector. The faciocervical scars were removed, forming wounds with areas of 9 cm×7 cm-28 cm×12 cm, and the perforators of superficial temporal artery and vein or facial artery and vein were preserved during the operation. The flaps were designed according to the area and size of the wounds after scar resection with the dominant IMAP as the pedicle. Single-pedicle IMAP flaps were used to repair small and medium-sized wounds. For larger defects, the blood perfusion areas of vessels in the anterior chest were evaluated by indocyanine green angiography (ICGA). In situations where the IMAP was insufficient to nourish the entire flap, double-pedicle flaps were designed by using the thoracic branch of supraclavicular artery or lateral thoracic artery for supercharging. Pedicled or free flap transfer was selected according to the distance between the donor areas and recipient areas. After transplantation of flaps, ICGA was conducted again to evaluate blood perfusion of the flaps. The donor sites of flaps were all closed by suturing directly. Statistics were recorded, including the number, rated capacity, normal saline injection volume, and expansion period of skin and soft tissue expanders, the location of the dominant IMAP, the total number of the flaps used, the number of flaps with different types of vascular pedicles, the flap area, the flap survival after the second stage surgery, the occurrence of common complications in the donor and recipient areas, and the condition of follow-up. Results: Totally 25 skin and soft tissue expanders were used in this group of patients, with rated capacity of 200-500 mL, normal saline injection volume of 855-2 055 mL, and expansion period of 4-16 months. The dominant IMAP was detected in the second intercostal space (20 sides) or the third intercostal space (5 sides) before surgery. A total of 25 expanded flaps were excised, including 2 pedicled IMAP flaps, 11 free IMAP flaps, 4 pedicled thoracic branch of supraclavicular artery+free IMAP flaps, and 8 free IMAP+lateral thoracic artery flaps, with flap areas of 10 cm×8 cm-30 cm×14 cm. After the second stage surgery, tip necrosis of flaps in three patients occurred, which healed after routine dressing changes; one patient developed arterial embolism and local torsion on the vascular pedicle at the anastomosis of IMAP and facial artery, and the blood supply recovered after thrombectomy and vascular re-anastomosis. Fourteen patients underwent flap thinning surgery in 1 month to 6 months after the second stage surgery. The follow-up for 4 months to 9 years showed that all patients had improved appearances of flaps and functions of face and neck and linear scar in the donor sites of flaps, and one female patient had obvious nipple displacement and bilateral breast asymmetry. Conclusions: The expanded IMAP flap is matched in color and texture with that of the face and neck, and its incision causes little damage to the chest donor sites. When combined with vascular supercharge, a double-pedicle flap can be designed flexibly to further enhance the blood supply and expand the flap incision area, which is a good choice for reconstruction of large faciocervical scar.

Time-Resolved Noncontrast Magnetic Resonance Perfusion Imaging of Paraspinal Muscles.

While evaluation of blood perfusion in lumbar paraspinal muscles is of interest in low back pain, it has not been performed using noncontrast magnetic resonance (MR) techniques. To introduce a novel application of a time-resolved, noncontrast MR perfusion technique for paraspinal muscles and demonstrate effect of exercise on perfusion parameters. Longitudinal. Six healthy subjects (27-48 years old, two females) and two subjects with acute low back pain (46 and 65 years old females, one with diabetes/obesity). 3-T, MR perfusion sequence. Lumbar spines of healthy subjects were imaged axially at L3 level with a tag-on and tag-off alternating inversion recovery arterial spin labeling technique that suppresses background signal and acquires signal increase ratio (SIR) from the in-flow blood at varying inversion times (TI) from 0.12seconds to 3.5 seconds. SIR vs. TI data were fit to determine the perfusion metrics of peak height (PH), time to peak (TTP), mean transit time, apparent muscle blood volume (MBV), and apparent muscle blood flow (MBF) in iliocostal, longissimus, and multifidus. Imaging was repeated immediately after healthy subjects performed a 20-minute walk, to determine the effect of exercise. Repeated measures analysis of variance. SIR vs. TI data showed well-defined leading and trailing edges, with sharply increasing SIR to TI of approximately 500 msec subsiding quickly to near zero around TI of 1500 msec. After exercise, the mean SIR at every TI increased markedly, resulting in significantly higher PH, MBV, and MBF (each P < 0.001 and F > 28.9), and a lower TTP (P < 0.05, F=4.5), regardless of the muscle. MBF increased 2- to 2.5-fold after exercise, similar to the expected increase in cardiac output, given the intensity of the exercise. Feasibility of an MR perfusion technique for muscle perfusion imaging was demonstrated, successfully detecting significantly increased perfusion after exercise. 1 TECHNICAL EFFICACY STAGE: 1.

Mucosal Congestion on the First Day Following Endoscopy Predicts Anastomotic Stricture After Esophagectomy.

Anastomotic stricture is a relatively common postoperative complication after esophagectomy. Previous studies have indicated that impaired perioperative blood perfusion at the anastomosis is associated with the occurrence of stricture. Therefore, we analyzed the association between endoscopically assessed blood perfusion during the early postoperative period and anastomotic stricture. This retrospective study evaluated patients who underwent esophagectomy at Tokyo Medical and Dental University between 2010 and 2015. The patients had undergone nasal endoscopy on the 1st and 8th postoperative days. The findings were used to evaluate blood perfusion at the anastomosis and gastric tube, which was classified based on mucosal color as ischemia (white) or congestion (blue or black). Univariate and multivariable logistic regression analyses were performed to identify risk factors for anastomotic stricture. The study included 197 patients and anastomotic stricture was observed in 60 patients (30.4%). The multivariable analysis revealed that postoperative gastric tube congestion was a risk factor for stricture (odds ratio [OR]: 6.440, 95% confidence interval [CI]: 2.660-15.600; p < 0.001). Lower risks of anastomotic stricture were associated with pathological stage III-IV disease (OR: 0.325, 95% CI: 0.161-0.656; p = 0.002). This study revealed that endoscopically detected congestion at the anastomosis on the first postoperative day was a risk factor for anastomotic stricture.

Quantitative Evaluation of Renal Cortex Perfusion Using Contrast-Enhanced Ultrasound Imaging Parameters in Ischemia–Reperfusion Injury in Rabbits

The aim of this study was to evaluate blood perfusion of the renal cortex during ischemia–reperfusion (I/R) injury using quantitative contrast-enhanced ultrasound (CEUS) parameters. In this experiment, 24 rabbits were randomly divided into four groups (N = 6): sham-operated group, 24-h post-operation for I/R injury group (24-h I/R), 3-d post-operation for I/R injury group (3-d I/R) and 5 d post-operation for I/R injury group (5 d I/R). All quantitative CEUS parameters were monitored and included the gradient from the start frame to the peak frame (Grad), area under the curve (Area), time-to-peak (TTP), difference between B(intercept intensity at t=0) and A(the intensity attenuation t= 0) and arrival time (AT). Subsequently, we analyzed the changes in these parameters, as well as the correlation between changes in CEUS parameters and pathological parameters. AT and TTP values peaked 3 d after I/R surgery, which correlated with the most significant pathological changes at the same time point. These parameters (such as AT, TTP and Grad) may be useful in dynamically monitoring the severity of tissue damage at the early stage of I/R injury.

Digital Subtraction Angiography Contrast Material Transport as a Direct Assessment for Blood Perfusion of Middle Cerebral Artery Stenosis.

Digital subtraction angiography (DSA) is a fluoroscopic technique used extensively in interventional radiology for visualizing blood vessels. It has also been used to evaluate blood perfusion. However, the perfusion obtained in previous techniques was extracted from signal intensity rather than by the transport of contrast material (CM) through blood flow. The main aim of this study is to evaluate the morphological effects on the hemodynamics and the CM concentration in the middle cerebral artery (MCA) stenosis. We proposed a quantitative parameter, i.e., contrast material remaining time (CMRT), to describe the variation in the transport of CM over time. Computational fluid dynamics simulations were performed on both reconstructive synthetic and patient-derived models. In the synthetic models, we evaluated the variation of flow patterns and the transport of CM with different degrees of stenosis and the location of the lesion. It was found that an increase in the degree of stenosis (from 30 to 80%) resulted in a significant increase in CMRT at the anterior cerebral artery (ACA) outlet (p = 0.0238) and a significant decrease in CMRT at the MCA outlet (p = 0.012). The patient-derived models were reconstructed from the pre- and post-interventional DSA images of a patient with MCA stenosis. Both blood flow velocity and CMRT increased at the ACA outlet but decreased at the MCA outlet. The perfusion analysis demonstrated that the perfusion function was improved after interventional surgery. In conclusion, changes in stenotic degree at MCA may lead to apparent differences in the hemodynamic distribution and the transport of CM. CMRT could be a quantitative indicator to evaluate the changes in blood perfusion after the intervention for MCA stenosis.

Peripheral blood perfusion in patients with systemic lupus erythematosus and in primary Raynaud's phenomenon.

This study aims to evaluate blood perfusion (BP) in various cutaneous regions of the hands and face in patients with systemic lupus erythematosus (SLE) and primary Raynaud's phenomenon (PRP) and healthy subjects (HS). A total of 20 patients with SLE, 20 patients with PRP, and 20 HS were enrolled. BP was detected by laser speckle contrast analysis in different regions of the hand and at the facial level. The absolute nailfold capillary number (CN) was assessed by nailfold videocapillaroscopy. Patients with SLE and PRP had significantly lower BP levels than those of HS in 3 hand areas (fingertip, palm, and periungual; p<0.01). However, the SLE, PRP, and HS groups had comparable BP values at the hand dorsum and face. The BP and CN values revealed a positive correlation in the periungual, fingertip, and palm of hands (p<0.01), only in patients with SLE. Our data demonstrated a correlation between functional and morphological microvascular impairment in patients with SLE.

Intraoperative Thermal Imaging for Evaluating Blood Perfusion During Laparoscopic Colorectal Surgery.

Anastomotic leakage is a feared complication of anterior resection for rectal cancer. Among the various factors reported to be involved in the occurrence of anastomotic leakage, blood perfusion of the remnant intestine is one of the most important. Recently, the usefulness of evaluating blood perfusion using indocyanine green (ICG) has been reported. We therefore aimed to show that measuring intestinal temperature using thermography is useful for evaluating blood perfusion. The authors also investigated the relation between intestinal temperatures and the ICG fluorescence time (FT). Altogether, 45 patients who underwent laparoscopic anterior resection for rectal cancer between July 2017 and September 2018 were enrolled in this study. ICG FT and intestinal temperature were measured after the mesenteric dissection. The temperature boundary could be easily identified using thermographic images. The temperature of the residual intestinal tract was significantly higher than that of the resected intestinal tract at the planned separation line (29.9 vs. 27.3°C). In addition, there was an inverse correlation between the ICG FT and the temperature of the residual intestine. Intestinal temperature measurement through thermography is a useful new tool for evaluating intestinal blood perfusion.

Evaluation of Blood Perfusion in the Myometrium of Women with Symmetric Uterine Anomalies Using Dynamic Contrast-Enhanced MRI.

Study Objective The objective of our study is to evaluate functional/dynamic enhanced MRI evaluation of the vascular (capillary) circulation of the myometrium and intrauterine septum in patients with symmetric uterine anomalies. Design Prospective cohort study, Level II. Setting National Medical Research Center for Obstetrics, Gynecology and Perinatology, Moscow, Russia. Patients or Participants 247 patients of patients with symmetric uterine anomalies were evaluated and treated between 2015 and 2020 at the department of operative gynecology. Interventions Surgical correction of genital malformations was performed in accordance with clinical manifestations: miscarriage or infertility. The new method of functional/dynamic contrast enhanced (DCE) MRI was employed in order to estimate uterine blood perfusion in symmetric uterine malformations. Dynamic monitoring of serial images evaluated the blood supply in the myometrium and septum by digital diagram and color-mapping. Measurements and Main Results The functional MRI was performed in 72 patients requiring surgery, and 30 patients managed without surgical correction. Microcirculation was reduced by over 32 % in most (87%) patients with sub-septate uterus, and in 46% of patients with complete uterine septum, increasing the need for hysteroresectoscopic metroplasty in these patients. Histopathologic evaluation of the resected septi identified the presence of significant uterine dysmorphogenesis, vascular malformations, and deep myometrial fibrosis. The asymmetric perfusion of the duplicate uterus was detected in 85% of patients, because the myometrial blood perfusion was reduced much more 22% in hemi-uteri. Successful pregnancy progressed in hemi-uteri with better perfusion results (p Conclusion Functional/dynamic-enhanced MRI identifies the degree of blood perfusion in the myometrium and intrauterine septi of women with symmetric uterine anomalies and may assist in development of surgical and assisted reproductive strategies in the management of these patients.

Heterogeneous Features of Keloids Assessed by Laser Speckle Contrast Imaging: A Cross-Sectional Study.

Keloids are described as benign dermal fibroproliferative lesions, and vascularization may play a significant role in their pathogenesis. In this study, laser speckle contrast imaging (LSCI) was used to assess perfusion within keloids and surrounding skin, and perfusion of keloids at different stages was compared. A total of 59 patients with 110 untreated keloids on the anterior chest were enrolled in this study. Different keloid stages (progressive, stable, and regressive) were defined according to patients' descriptions of whether keloids became larger, stable, or smaller during the previous year. Vancouver Scar Scale (VSS) was assessed by a plastic surgeon, and patient reports on pain and itching were documented. LSCI was used to evaluate blood perfusion of keloids (K), skin adjacent to keloids (A), and nonadjacent skin (N). The mean perfusion of these regions was determined, and ratios (K/N, A/N) were calculated. A heterogeneous perfusion map was observed among the keloid groups, as well as within each keloid. A positive correlation was found between keloid perfusion and VSS. There were 62 (56.4%) keloids in the progressive stage, 33 (30.0%) keloids in the stable stage, and 15 (13.6%) keloids in the regressive stage. The mean K/N ratios in the progressive, stable, and regressive stages were 2.3 ± 0.5, 1.8 ± 0.3, and 1.5 ± 0.5, respectively. The mean A/N ratios were 1.2 ± 0.4, 1.2 ± 0.2, and 1.0 ± 0.5, respectively. Within each keloid, significantly higher perfusion was noted in the keloid and adjacent skin compared with nonadjacent skin. These results indicate that LSCI is a promising technique for evaluating keloid blood perfusion and distinguishing heterogeneous keloids. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Functional (Dynamic Contrast-Enhanced) MRI Assists in the Evaluation of Blood Perfusion in Myometrium and Intrauterine Septi of Women with Symmetric Uterine Anomalies

Study Objective Successful reproductive outcomes of patients with uterovaginal anomalies remain in the range of 25-37%, despite applying minimally invasive surgical corrections and assisted reproductive methods. The objective of our study is to introduce functional/dynamic enhanced MRI evaluation of the vascular circulation of the myometrium and intrauterine septum in patients with symmetric uterine anomalies. Design Prospective cohort study. Setting National Medical Research Center for Obstetrics, Gynecology and Perinatology, Moscow, Russia. Patients or Participants 213 patients of patients with symmetric uterine anomalies were evaluated between 2015 and 2017 at our department. Interventions Surgical correction of genital malformations was performed in accordance with clinical manifestations: obstruction of menstrual outflow, abdominal pain, infertility, miscarriage, sexual problems. The new method of functional/dynamic contrast enhanced (DCE) MRI was employed in order to estimate uterine blood perfusion in symmetric uterine malformations. Dynamic monitoring of serial images evaluated the blood supply in the myometrium and septum by digital diagram and color-mapping. Measurements and Main Results The functional MRI was performed in 42 patients requiring surgery, and 30 patients managed without surgical correction. Microcirculation was reduced by over 32 % in most patients with sub-septate uterus, and in 46% of patients with complete uterine septum, increasing the need for hysteroresectoscopic metroplasty in these patients. Histopathologic evaluation of the resected septi identified the presence of significant uterine dysmorphogenesis, vascular malformations, and deep myometrial fibrosis. The asymmetric perfusion of the duplicate uterus was detected in 85% of patients. Successful pregnancy progressed in hemi-uteri with better perfusion results (p Conclusion Functional/dynamic-enhanced MRI identifies the degree of blood perfusion in the myometrium and intrauterine septi of women with symmetric uterine anomalies and may assist in development of surgical and assisted reproductive strategies in the management of these patients.

Quantitative evaluation of blood perfusion in hepatocellular carcinoma after transcatheter arterial chemoembolization by contrast-enhanced ultrasound

Quantitative evaluation of blood perfusion in hepatocellular carcinoma after transcatheter arterial chemoembolization by contrast-enhanced ultrasound

Diagnostic value of computed tomographic perfusion imaging of whole liver for quantitative assessment of blood flow state in liver cancer after transcatheter arterial chemoembolization

Objective: To investigate the diagnostic value of whole liver CT perfusion imaging in the quantitative evaluation of hemodynamic changes before and after transcatheter arterial chemoembolization (TACE). Methods: Twenty-six patients with hepatocellular carcinoma underwent TACE therapies were recruited. Whole -liver computed tomographic perfusion imaging (CTPI) was performed 2~3 days before TACE and 1 month after TACE. We measured the following perfusion parameters: hepatic arterial perfusion (HAP), portal venous perfusion (PVP), total liver perfusion (TLP), hepatic arterial perfusion index (HAPI), and time-to-peak (TTP).The F-test, t-test and Rank sum test were used for statistical analysis. Results: A total of 34 HCC lesions were detected. According to the deposition of lipiodol after TACE, they were divided into a lipiodol dense group (21) and a lipiodol light group (13). The length of hepatocellular carcinoma lesions after TACE showed a decreasing trend compared with preoperative TACE. The lesions in the lipiodol dense group had smaller lesions than those in the lipiodol light group. The preoperative and postoperative longitudinal diameters were (3.12 ± 0.58) cm vs. (1.93 ± 0.79) cm, (2.98 ± 2.01) cm vs. (2.58 ± 2.00) cm, the differences were statistically significant (t = 15.1, 8.65, P < 0.05). The preoperative HAP and HPI of the lipiodol dense group were the highest, and the peritumoral within 1cm was higher than that of the surrounding liver parenchyma. The PVP, TLP, and TTP were highest in the surrounding of liver parenchyma, and 1 cm higher than the tumor area in the background. The corresponding perfusion parameters were statistically significant (P < 0.05); HAP and HPI were 1 cm higher than the surrounding liver parenchyma. After the operation, PVP, TLP and TTP were lower than the background liver parenchyma, the difference was statistically significant (P < 0.05); HAP and HPI decreased by 1 cm after the operation, and the PVP, TLP, and TTP increased. There was no significant difference after operation in the blood perfusion of background liver parenchyma (P ˃ 0.05). The HAP and HPI decreased, and the PVP and TTP increased in the lipiodol light group after operation (P < 0.05). There was no significant difference between the other two regions (P ˃ 0.05). Conclusion: There was no blood perfusion in the lipiodol deposition area after TACE. The perfusion volume of hepatic artery in the peritumoral 1 cm and lipiodol light group decreased and the portal venous perfusion increased. CTPI can quantitatively evaluate blood perfusion state, which is of great significance for the determination of treatment plans before TACE treatment to assume the postoperative therapeutic effect in liver cancer.

Laser Doppler Flowmetry versatile acquisition system with low quantization error

The Laser Doppler Flowmetry (LDF) is a non-invasive technique used to evaluate blood perfusion of various human tissues like the skin or the fundus of the eye. It is based on the scattering of light on moving red blood cells in tissue. Frequency shifted scattered light is detected and provide an electrical signal. Physical models for LDF use the DC and AC components of this signal. If AC is small relative to the DC, digitalization becomes an issue, and if more than two LDF signal acquisitions and analysis have to be done simultaneously, the device becomes expensive and bulky. We propose here a versatile and inexpensive acquisition system, which overcomes quantization errors issue by first separating DC from AC, then amplifying AC and finally recombining both signals before digitalization. We designed an analog circuit combined with a 12 bit analog-to-digital converter, a microcontroller unit and a Raspberry Pi2 (Rpi2) for the signal processing. Results are accessed remotely from the Rpi2 through HTTP protocol. Multiple systems can easily be used simultaneously for multichannel acquisitions.

A preliminary study of rat posterior thigh perforator flap model and its blood perfusion evaluation method

Objective To establish posterior thigh perforator flap model in rats and detect effective methods for evaluating flap blood perfusion. Methods Twelve Wistar rats were divided into 2 groups and left side was set as experimental side. The posterior thigh perforator flap was designed and pedicled with perforator artery of branch to the biceps femoris muscle (PABBFM). The flap was divided into the perforator pedicle group and trunk pedicle group according to the vascular characteristics of the flap. Inner diameter and blood flow velocity of caudal femoral artery (CFA) and PABBFM were measured by high frequency color doppler flow imaging (HFCDFI) respectively, and all the data were analyzed statistically. The perfusion unit (PU) values and blood perfusion maps of two groups were observed by laser doppler perfusion imager (LDPI) at 2 hours, 1 day, 3 days, 5 days, 7 days and 14 days after the operation. Results The inner diameters of CFA in the perforator pedicle group and trunk pedicle group were (0.92±0.09) mm and (0.85±0.22) mm, respectively, and the blood flow velocities were (14.36±7.86) cm/s and (13.10±6.78) cm/s. The inner diameters of PABBFM in the perforator pedicle group and trunk pedicle group were (0.68±0.09) mm and (0.64±0.17) mm, respectively, and the blood flow velocities were (11.11±3.87) cm/s and (9.41±3.08) cm/s. There was no significant difference in blood vessel diameter and blood flow velocity between different groups (P>0.05). LDPI showed that the blood flow of the perforator pedicle group and the trunk flap presented different PU values at different time after operation, and the blood perfusion showed different changes with different rules. Conclusion The posterior thigh perforator flap can be divided into perforator and trunk type according to the vascular pedicle for easy cutting. HFCDFI can stably and accurately obtain the inner diameter and blood flow velocity of the flap. LDPI can be used to noninvasively and timely observe the blood supply of the flap after operation. Key words: Surgical flaps; Models,animal; High frequency ultrasound; Laser doppler

Contrast-Enhanced Ultrasonography of Pancreatic Carcinoma: Correlation with Pathologic Findings

We concluded that contrast-enhanced ultrasound (CEUS) has clinical value in identifying the pathologic changes of pancreatic carcinomas. Forty-three patients diagnosed with pancreatic carcinoma through surgery were retrospectively investigated. CEUS examinations were performed on all patients before surgery. Enhancement patterns on CEUS were observed. Time–intensity curves of CEUS were generated for the regions of interest in the pancreas, and quantitative parameters were obtained. Resected cancer specimens were stained with hematoxylin and eosin for histologic analysis, and the microvascular density (MVD) of the specimens was determined by CD34 immunohistochemical staining. Enhancement patterns of CEUS were compared with histopathologic findings in pancreatic carcinomas. Correlations between time–intensity curve parameters and microvascular density were analyzed. Twenty cases manifested centripetal enhancement, and 23 cases, global enhancement. The amount of tumor necrosis or mucus in the centripetally enhanced pancreatic carcinomas was greater than that in the globally enhanced pancreatic carcinomas (p = 0.027). Thirty-eight of 43 (88.4%) pancreatic carcinomas manifested hypo-enhancement with a maximum intensity (IMAX) <90%. Contrast arrival time in pancreatic carcinoma was longer than that in adjacent pancreatic tissue (p < 0.05). IMAX was positively correlated with microvascular density (r = 0.577, p < 0.05). We concluded that CEUS manifestations could reflect the histologic changes of pancreatic carcinomas and CEUS can be used to evaluate blood perfusion of tumors, as IMAX is positively correlated with microvascular density.