Different hemodynamic responses by color Doppler ultrasonography studies between sildenafil non-responders and responders

Aim： To determine if there are different penile hemodynamic patterns between sildenafil non-responders and responders by using color Doppler ultrasonography. Methods： A total of 69 erectile dysfunction （ED） patients aged 22-79 years were enrolled into the present study. Thirty-eight （55.1%） men with ED who did not respond to four attempts of treatment with 100 mg sildenafil after re-education were classified as sildenafil non-responders. A com- bination of three vasodilator drugs, 1.25 mg papaverine, 0.4 mg phentolamine and 5 ug prostaglandin E1, was given by intracavernous injection before penile Doppler ultrasonography was carried out. The erectile response to intracavernous injection and vascular parameters including peak systolic velocity （PSV）, resistance index （RI）, end diastolic velocity （EDV） and cavernosa artery diameter （CD） were measured and the results between sildenafil nonresponders and responders were compared. Results： No statistical difference in vascular parameters measured by Doppler ultrasonography studies between non-responders and responders was noted. Sildenafil non-responders had a poorer penile rigidity response to intracavernous injection than responders （P 〈 0.05）. Among patients with adequate PSV （〉 30 cm/s） and abnormal EDV （〉 5 cm/s）, individuals in the non-responder group had fewer positive responses to intracavernous vasodilator injection than in the responder group （35.3% vs. 72.2%, P 〈 0.05）. Advanced age and comorbidity with diabetes mellitus were significantly associated with sildenafil non-response （P 〈 0.05）. Conclusion： Sildenafil non-responders were characterized by a poorer penile rigidity response to intracavernous injection and had an associated impaired veno-occlusive mechanism. Advanced age and comorbidity with diabetes mellitus were two common factors associated with non-response.

Use of color Doppler ultrasonography in the diagnosis of anomalous connection in pancreatobiliary disease

AIM: To estimate the detectability of anomalous connection in pancreatobiliary disease (ACPBD) cases, measuring gallbladder wall blood flow (GWBF).METHODS: In the retrospective study, we enrolled 42subjects with gallbladder wall thickening. GWBF velocity was determined as an average value of the peak velocity of color signals on the gallbladder wall, three times in each case. Based on the findings on endoscopic ultrasonography (EUS) or endoscopic retrograde cholangiopancreatography (ERCP), the 42 subjects were divided into 11 cases with ACPBD and 31 cases without ACPBD. In the prospective study, the subjects were 92 cases with gallbladder wall thickening. Using the cut-off level of the flow velocity obtained in the retrospective study, the usefulness of measuring GWBF velocity in diagnosing ACPBD was evaluated.RESULTS: In the retrospective study, imaging of GWBF was obtained in 40 of the 42 subjects. The mean GWBF velocity of the ACPBD cases was 29.4±3.9 cm/s(mean±SD), which was significantly different (P＜0.0001;95% CI 5.48-13.2) from that of the without ACPBD cases(20.1±5.9 cm/s). Based on this result, we prepared a receiver operating characteristic curve, and the cut-off level appropriate for diagnosing ACPBD was estimated to be 25 cm/s. In the prospective study, GWBF was detected in 86 of the 92 subjects. Based on the EUS or ERCP findings, the 92 subjects were divided into 15 cases with ACPBD and 77 cases without ACPBD. When a cut-off level of 25 cm/s was employed, ACPBD could be diagnosed with a sensitivity of 87.0% (13/15) and a specificity of87.3% (62/71).CONCLUSION: Measurement of GWBF velocity, which is less invasive and provides objective values, is very useful for diagnosing ACPBD prior to the development of malignant tumors in cases with gallbladder wall thickening.

The value of color Doppler ultrasonography in monitoring normal orthotopic liver transplantation and postoperative complications

OBJECTIVE: To assess the value of color Doppler ultrasonography in monitoring normal orthotopic liver transplantation and postoperative complications. METHODS: Forty-one patients after orthotopic liver transplantation were examined by using color Doppler flow imaging to observe the hepatic blood flow and change of ultrasonography of the hepatic parenchyma and bile duct. The measured indexes included maximum blood flow velocity, time-average blood flow velocity (TAV), resistance index (RI) and diameter of the bile duct. RESULTS: Among 41 patients, 17 (41.5%) suffered from liver transplant rejection. Of the 17 patients, 13 (76.4%) showed decrease of TAV of the portal vein, 15 (88.25%) low-amplitude single-phase serrated wave or negative biphasic wave of the hepatic vein, 9 (52.9%) increased hepatic arterial RI, and 5 (29.4%) slightly dilated bile duct. Sonography showed disappearance of the hepatic artery blood flow around the portal vein in 5 (12.2%) of the 41 patients with hepatic artery thrombosis in the postoperative period. Slight dilatation of the intrahepatic bile duct was found in 3 (7.3%) of the 41 patients in the early postoperational period and it normalized within 2 weeks. Ultrasonography of 20 patients (48.8%) revealed a visible dilatation of the intrahepatic bile duct, which was worsening gradually. The causes of bile duct dilatation included biliary stricture in 2 patients (10%), stone in 15 patients (75%) and others in 3 patients (15%). CONCLUSIONS: Color Doppler ultrasonography is valuable for monitoring normal liver transplantation and postoperative complications.

Transcranial Doppler ultrasonography: From methodology to major clinical applications

Non-invasive Doppler ultrasonographic study of cerebral arteries [transcranial Doppler(TCD)] has been extensively applied on both outpatient and inpatient settings. It is performed placing a low-frequency(≤ 2 MHz) transducer on the scalp of the patient over specific acoustic windows, in order to visualize the intracranial arterial vessels and to evaluate the cerebral blood flow velocity and its alteration in many different conditions. Nowadays the most widespread indication for TCD in outpatient setting is the research of right to left shunting, responsable of so called "paradoxical embolism", most often due to patency of foramen ovale which is responsable of the majority of cryptogenic strokes occuring in patients younger than 55 years old. TCD also allows to classify the grade of severity of such shunts using the so called "microembolic signal grading score". In addition TCD has found many useful applications in neurocritical care practice. It is useful on both adults and children for day-to-day bedside assessment of critical conditions including vasospasm in subarachnoidal haemorrhage(caused by aneurysm rupture or traumatic injury), traumatic brain injury, brain stem death. It is used also to evaluate cerebral hemodynamic changes after stroke. It also allows to investigate cerebral pressure autoregulation and for the clinical evaluation of cerebral autoregulatory reserve.

Postoperative complications in patients with portal vein thrombosis after liver transplantation:Evaluation with Doppler ultrasonography

AIM： To study the postoperative complications in patients with preoperative portal vein thrombosis （PVT） undergoing liver transplantation （LT） and to evaluate the complications with Doppler ultrasonography.METHODS： Retrospective studies were performed on 284 patients undergoing LT （286 LT） with respect to pre- and postoperative clinical data and Doppler ultrasonography. According to the presence and grade of preoperative PVT, 286 LTs were divided into three groups： complete PVT （c-PVT）, partial PVT （p-PVT） and non-PVT, with 22, 30 and 234 LTs, respectively. Analyses were carried out to compare the incidence of early postoperative complications.RESULTS： PVT, inferior vena cava （IVC） thrombosis, hepatic artery thrombosis （HAT） and biliary complications were found postoperatively. All complications were detected by routine Doppler ultrasonography and diagnoses made by ultrasound were confirmed by clinical data or/and other imaging studies. Nine out of 286 LTs had postoperative PVT. The incidence of the c-Pv-r group was 22.7%, which was higher than that of the p-Pv-r group （3.3%, P 〈 0.05） and non- PVT group （1.3%, P 〈 0.005）. No difference was found between the p-PVT and non-PVT groups （P 〉 0.25）. Of the 9 cases with postoperative PVT, recanalizations were achieved in 7 cases after anticoagulation under the guidance of ultrasound, 1 case received portal vein thrombectomy and 1 case died of acute injection. Ten LTs had postoperative 1VC thrombosis. The c-PVT group had a higher incidence of IVC thrombosis than the non- PVT group （9.1% vs 2.6%, P 〈 0.05）; no significant difference was found between either the c-PV-T and p-PVT groups （9.1% vs 6.7%, P 〉 0.5） or between the p-PVT and non-PVT groups （P 〉 0.25）. Nine cases with IVC thrombosis were cured by anticoagulation under the guidance of ultrasound, and 1 case gained natural cure without any medical treatment after 2 mo. HAT was found in 2 non-PVT cases, giving a rate of 0.7% among 286 LTs. Biliary complications were seen in 12 LTs. The incidence of biliary complications in the c-PVT, p-PVT and non-PVT groups was 9.1%, 3.3% and 4.3%, respectively （P 〉 0.25 for all）, among which 2 stenosis led retransplantations and others were controlled by relative therapy.CONCLUSION： C-PVT patients tend to have a higher incidence of PVT and IVC thrombosis than non- PVT patients after LT. The incidence of postoperative complications in p-PVT patients does not differ from that of non-PVT patients, A relatively low incidence of HAT was seen in our study, Doppler ultrasonography is a convenient and efficient method for detecting posttransplant complications and plays an important role in guiding treatment.

A COMPARATIVE STUDY OF TRANSVAGINAL ULTRASONOGRAPHY AND PELVIC ARTERIOGRAM IN ASSESSMENT OF PATIENTS WITH GESTATIONAL TROPHOBLASTIC TUMOUR

Objective:To compare the reliability of transvaginal ultrasonography with pelvic arteriography in the assessment of patients with gestational trophoblastic disease. Methods. Transvaginal ultrasonography was performed in 24 patients with gestational trophoblastic tumour. Within one week after ultrasound investigation, pelvic arteriography was carried out in each patient. Of 24 cases, 16 patients hadn’t been treated by chemical reagent, 5 had accepted 2 to 5 courses of chemotherapy, and 3 had achieved complete remission before both investigations performed. Results. In 3 patients with complete remission, 2 had no evidence of abnormal findings either on transvaginal ultrasonography or on pelvic arteriography, 1 showed intramyometrial lesions by both methods. In the remaining 21 patients, all demostrated a abnormal uterine image, and 5 of them accompanied with the finding of parametrium metastatic signs by transvaginal ultrasonography; these abnormal results were confirmed by pelvic arteriographic imaging. However, in two cases without clinical and ultrasonic signs of parametrium metastasis, pelvic arteriography indicated the early metastasis of parametrium ves- sels. Conclusions. Even though it is difficult to predict the early parametrium metastasis in patients with gestational trophoblastic disease by B-ultrasonic investigation, our data would support the introduction of transvaginal ultrasonography in the diagnosis and evaluation of gestational trophoblastic tumour.

Hemodynamics in the portal vein evaluated by pulse wave Doppler ultrasonography in patients with chronic hepatitis C treated with interferon

AIM: To employ pulse wave Doppler ultrasonography to evaluate the changes in portal blood flow velocity in patients with chronic hepatitis C (CHC) receiving interferon (IFN) treatment. METHODS: The subjects in this study were 14 patients (13 men and l woman) with CHC who received IFN treatment. Portal blood flow velocity was measured in the vessels at the porta hepatis at four time points: before IFN administration (pre-IFN), 2 wk after the start of administration (wk 2), 24 wk after the start of administration (wk 24, i.e., the end of IFN administration), and 24 wk after the end of administration (wk 48). RESULTS: The patients with CHC in whom IFN treatment resulted in complete elimination or effective elimination of viruses showed a significant increase in portal blood flow velocity at the end of IFN treatment compared with that before IFN treatment. In contrast, when IFN was ineffective, no significant increase in portal blood flow velocity was observed at wk 24 or 48 compared with the pre-IFN value. In addition, the patients with CHC in whom IFN was ineffective showed significantly lower portal blood flow velocity values than control subjects at all measurement time points. CONCLUSION: Pulse wave Doppler ultrasonography is a noninvasive and easily performed method for evaluating the effects of IFN treatment in patients with CHC. This technique is useful for measuring portal blood flow velocity before and 24 wk after IFN administration in order to evaluate the changes over time, thus assessing the effectiveness of IFN treatment.

COLOR DOPPLER ULTRASONOGRAPHY APPEARANCES OF RENAL VEIN THROMBOSIS AND ITS DIAGNOSTIC VALUE

Objective To evaluate color Doppler ultrasonography (CDU) appearances of renal vein thrombosis (RVT) and its diagnostic value.Methods Ten patients with RVT were analyzed retrospectively. Renal structure, distributions of intrarenal flow signals, echogenicity, and flow fullness in main renal veins were observed with CDU. Resistance index (RI) was recorded from the waveforms of segmental or interlobar renal artery.Results Ten kidneys in nine patients were confirmed to have thrombus within the main renal veins, and one patient was confirmed to have thrombus within the small intrarenal veins. The appearances of the main renal vein thrombosis included full of solid echogenicity or strip echogenicity and complete or partial filling defect within the main renal veins, and absent or a few intrarenal venous flow signals in 70% of kidneys involved. The appearances of intrarenal vein thrombosis included obscure renal structure and no venous flow signal within the involved part of the kidneys. Reverse diastolic flow in the intrarenal artery had only a sensitivity of 36% (4/11); in other 7 kidneys without intrarenal arterial reverse diastolic flow, increased RI (mean, 0.84; range, 0.74-0.96) was found.Conclusion CDU is helpful for rapid clinical diagnosis and follow-up of RVT, and therefore can be the first imaging modality of choice for RVT.

Transvaginal color Doppler monitoring of medicinal termination of early pregnancy: analysis of prolonged bleeding and choice of indications

Objectives:To observe trophoblastic and other blood flows after medicinal abortion, to analyze factors of prolonged bleeding, and to determine indications for medicinal termination of early pregnancy. Methods:Transvaginal color Doppler (TVCD) observation in combination with β--hCG determination in clinical trial involving 145 early pregnant women. Results: In cases of prolonged bleeding trophoblastic blood flow (TBF) is more significant. After aspiration of retained tissues, parallel to disappearance of TBF, prolonged uterine bleeding is stopped. Ectopics, lower--situated myoma and scar--site--implantation are relatively contraindicative for medicinal abortion. Too early pregnancy with too small embryonic--sac is not favourable. The sac is more difficult to be expelled. Prolonged bleeding can occur in cases of amenorrhea or recovery of menstruation due to retention of decidual tissues with microvilli. Conclusion: Retention of decidual tissues with microvilli plays an important role in the mechanism of prolonged uterine bleeding during medicinal termination of early pregnancy. TVCD is very helpful in monitoring this method. Ectopic pregnancy should be contraindicated. In cases of myoma or with history of cesarean section the location of implantation and myoma or scar should be examined by ultrasound before decision. Pregnancy of 6--7 weeks is more favorable for medicinal abortion.

TRANSVAGINAL COLOR DOPPLER STUDY OF UTEROPLACENTAL CIRCULATION IN NORMAL EARLY PREGNANCY

A cross sectional transvaginal color Doppler study of the uteroplacental circulation was performed on 105 pregnant women with normal intrauterine pregnancy. Gestational age was ranged from 4 to 12 weeks. The blood flow velocity waveforms were obtained from four separate parts of the uteroplacental circulation: uterine, arcuate, radial, and spiral arteries. The resistance index (RI) and peak systolic velocity (PSV) were analyzed. The RI significantly decreased and PSV increased with advancing gestation in uterine artery and its branches (P<0 05). The RI gradully decreased from uterine artery through arcuate, radial to spiral arteries (P<0 05). At the same time, the PSV decreased from uterine artery then arcuate to radial artery, but PSV in spiral arteries were higher than that in radial artery (P<0 05). The results showed that transvaginal color Dopper ultrasonography was a simple, reliable method to assess the uteroplacental circulation in the early pregnancy; the detection of PSV was useful parameter for better understanding of physiological and pathophysiological hemodynamic changes as well as RI.

Graves' Disease Thyroid Color-Flow Doppler Ultrasonography Assessment: Review Article

Graves’ disease, as known today, is an autoimmune, diffuse, chronic disease of thyroid gland, as described by Robert Graves in 1835. It presents genetic predisposition and unknown etiology evidence, which is influenced in its development by several factors, including environment (dietary iodine intake, stress, drugs and infections). The disease is characterized by one or more changes: hyperthyroidism, goiter, ophthalmopathy, skin changes and pretibial myxedema, around 5% less common, and other symptoms 90% to 95%. One of the most relevant clinical practice aspects in Graves’ disease patients management is to distinguish Graves’ disease in initial phase, from other types of destructive thyrotoxicosis, in addition to evaluate therapeutic methods and efficient follow up, as well as predict early recurrence or remission of disease. Scintigraphy with pertechnetate (99 mTc) and TSH levels dosage are considered the choice for this purpose. However, they present some technical difficulties, as they are not widely available and have contraindications. In this scenario, thyroid color-flow doppler ultrasonography (US Doppler) presents a viable alternative, as a widely available, low cost, non-invasive and radiation free method, providing initial diagnosis and patients with Graves’ disease follow up. In adittion, this method is used in differential diagnosis with other causes of thyrotoxicosis in the early stage.

Accuracy of Doppler Ultrasonography in Assessment of Lower Extremity Peripheral Arterial Diseases

Doppler ultrasound scan is a non-invasive, cheap and convenient tool and it complements angiography, Computed tomography angiography (CTA), magnetic resonance angiography (MRA) and catheter digital subtraction angiography (DSA) in screening, diagnosis, treatment and follow-up of peripheral vascular diseases. Symptoms of peripheral vascular diseases are becoming more common due to rise in incidence of diseases and risk factors (diabetes mellitus, dyslipidemias, smoking, sedentary lifestyle). Due to limited availability of highly specific tools such as CT angiography, magnetic resonance angiography (MRA) and DSA (digital subtraction angiography) in many developing countries, doppler ultrasound is gaining more importance. Early determination of peripheral arterial diseases is beneficial in prevention of complications as severity increases may cause intermittent claudication, pain, tissue loss, including ulceration and gangrene (as the diseases progresses) and early management of arteriosclerosis will be beneficial to prevent these complications.

A study of the hypoechoic hypertrophic lesions and hypoechoic cancer lesions in hypertrophic prostate inner glands with transrectal color doppler ultrasonography

Objective: To observe the sonographic and hemodynamic features of hypoechoic hypertrophic lesions and hypoechoic cancer lesions in the hypertrophic prostate inner glands, in order to raise the accuracy of early diagnosis rate for prostate cancer. Methods: 31 cases of hypoechoic hypertrophic lesions and 18 cases of hypoechoic cancer lesions in the hypertrophic prostate inner glands were observed by transrectal ultrasonography and comparatively analyze the shape, edge and the systolic peak velocity (Vs) , resistance index (RI) and pulsatility index (PI) of the lesions. Results: In contrast with hypertrophic group, the cancer group presented irregular shape and unclear edge, and obviously higher Vs, RI and PI. Conclusion: The sonographic appearance and Vs. RI. PI have important value in distinguishing hypoechoic hypertrophic lesions and hypoechoic cancer lesions in the hypertrophic prostate inner glands.

Value of identifying and diagnosing mammary carcinoma and non-lactation mastitis lump by color Doppler ultrasonography

Objective: To evaluate the value of identifying and diagnosing mammary carcinoma and non-lactation mastitis lump (NLM) by multicolor Doppler ultrasonography. Methods: We compared and analyzed the examination results of 69 cases of mammary carcinoma proved by surgical pathology and 22 cases of NLM before surgery by multicolor Doppler ultra-sonography. Results: The detection rates of mammary carcinoma and NLM focus by ultrasonic examining were 100%. The shape, envelope, foul line, blood stream between sound and image of two diseases were similar. Of the two diseases, the representation with slight calcification in lump, lower echo in low echo, bloodstream distribution and resistance were different. Conclusion: By analyzing the sound and image representation of mammary lump, we find color Doppler ultrasonography has significant value in identifying and diagnosing mammary carcinoma and non-lactation mastitis lump.

Doppler Study of Uterine Artery and Ultrasonography of Endometrial Thickness in Perimenopausal and Postmenopausal Bleeding

Background: Transvaginal color Doppler sonography of the uterine artery has been reported useful for evaluation of abnormal uterine bleeding in peri-/post-menopausal women. It may differentiate physiological from malignant endometrial changes. Objective: Evaluating the endometrial thickness and uterine artery Doppler as an initial diagnostic tool to identify patients with abnormal endometrial pathology. Methods: This is a prospective case control study consisted of total 50 women with peri-(n = 35) and post-(n = 15) menopausal bleeding, with 20 women consisting control group (no bleeding) (peri-(n = 10) and post-menopausal (n = 10)). Double layer endometrial thickness and uterine-artery-Doppler waveforms were measured, with the latter being S/D ratio, RI and PI. These were related to histological findings (endometrial biopsy). Result: Patients with abnormal uterine bleeding (both peri- and postmenopausal) had a significantly higher mean endometrial thickness than the control women. Study group showed a significantly lower value of all Doppler indices (S/D ratio, RI and PI). In study group, patients with malignant endometrial pathology showed significantly thicker endometrium and significantly lower Doppler indices than those with benign pathology. Conclusion: The combination of endometrial thickness and uterine artery color Doppler pattern might predict uterine endometrial malignancy, although whether it can discriminate (screen) patients requiring endometrial biopsy is not evident. Further study is needed.

Point-of-care ultrasonography spotlight:Could venous excess ultrasound serve as a shared language for internists and intensivists?

Point-of-care ultrasonography(POCUS),particularly venous excess ultrasound(VExUS)is emerging as a valuable bedside tool to gain real-time hemodynamic insights.This modality,derived from hepatic vein,portal vein,and intrarenal vessel Doppler patterns,offers a scoring system for dynamic venous congestion assessment.Such an assessment can be crucial in effective management of patients with heart failure exacerbation.It facilitates diagnosis,quantification of congestion,prognostication,and monitoring the efficacy of decongestive therapy.As such,it can effectively help to manage cardiorenal syndromes in various clinical settings.Extended or eVExUS explores additional veins,potentially broadening its applications.While VExUS demonstrates promising outcomes,challenges persist,particularly in cases involving renal and liver parenchymal disease,arrhythmias,and situations of pressure and volume overload overlap.Proficiency in utilizing spectral Doppler is pivotal for clinicians to effectively employ this tool.Hence,the integration of POCUS,especially advanced applications like VExUS,into routine clinical practice necessitates enhanced training across medical specialties.

Can the change of vasomotor activity in irritable bowel syndrome patients be detected via color Doppler ultrasound?

BACKGROUND Irritable bowel syndrome(IBS)is one of the most frequently referred conditions to the gastrointestinal outpatient clinic.The pathophysiology of IBS has not been determined with certainty.Visceral hypersensitivity is indicated as one of the pathophysiologies.The sympathetic nervous system is primarily in charge of controlling the arteries,and its effect is vasospasm in the medium and large arteries,resulting in decreased blood flow.AIM To demonstrate,using Doppler evaluation of the brachial artery,that sympathetic activity impairs vasomotor performance due to autonomic neuropathy,which we believe is associated with IBS.METHODS There were 58 participants in the study.The control group consisted of 29 healthy patients,while the remaining 29 patients had been diagnosed with IBS.Patients who met the Rome IV criteria and had IBS were included in the study.People with known polyneuropathy or non-IBS chronic conditions that can progress were excluded from the trial,as were those with essential hypertension,diabetes mellitus,cardiovascular disease,or peripheral arterial disease,and patients diagnosed with anxiety or depression.Those with moderate to severe carpal tunnel syndrome or a median nerve lesion due to trauma were also excluded from the trial.A Doppler probe was used to measure the baseline diameter and flow rates of the brachial artery from 2 cm superior to the antecubital fossa.The Doppler probe remained stationary throughout the experiment,allowing for continuous measurements.Then,to activate the sympathetic fibers,an electrical stimulus for 5 s with an intensity of 10 mA and a frequency of 1 Hz was applied to the median nerve at the wrist level via the bipolar stimulus electrode.The artery diameter and flow rates were measured again immediately following the fifth stimulus.RESULTS In healthy persons with no history of chronic illness,there was a statistically significant decrease in flow rate after stimulation(P<0.001).In addition,stimulation resulted in a statistically significant reduction in the diameter of the brachial artery(P<0.001).Patients diagnosed with IBS had statistically significant vasodilation and an increase in flow rate.CONCLUSION Sympathetic stimulation causes a reduction in vascular diameter and blood flow,whereas it has the reverse effect on IBS patients.In investigating the involvement of autonomic neuropathy in the development of IBS,significant changes in brachial artery Doppler parameters were observed before and after stimulation of the median nerve with low-current sensory stimulation.This method is thought to be more user-friendly and comfortable than other methods described in the literature.

Monitoring of antegrade selective cerebral perfusion for aortic arch surgery with transcranial Doppler ultrasonography and near-infrared spectroscopy

Objective To evaluate the safety and efficacy of antegrade selective cerebral perfusion (ASCP) during aortic arch surgery as a means of extending the safe period of systemic circulatory arrest using multimodality neuromonitoring to objectively quantify the physiologic responses Methods In twenty two patients (all less than age 60) scheduled for repair of an aortic arch aneurysm, preoperative verification of effective collateral perfusion through both the carotid and vertebrobasilar arterial systems was documented with transcranial Doppler ultrasonography (TCD) During cardiopulmonary bypass, the sole arterial inflow from the pump was via the right subclavian artery The magnitude of ASCP was quantified by TCD using peak middle cerebral artery velocity, while flow adequacy was measured by continuous regional cerebrovenous oxygen saturation (rSO 2) using dual wavelength spatially resolved near infrared spectroscopy Results All patients experienced an uneventful recovery Flow in the middle cerebral artery became undetectable at ASCP < 5?ml·kg 1 ·min 1 , so adjustments from a 15-20?ml·kg 1 ·min 1 baseline were used to maintain rSO 2 above 50% Furthermore, ASCP flow was highly correlated ( P <0 01) with both peak middle cerebral artery velocity and rSO 2 ( r =0 86 and 0 96, respectively) Conclusion Neuromonitoring guided ASCP may be expected to extend the safe period and is at least partly responsible for the absence of neurologic complications in this patient cohort

Contrast-enhanced endoscopic ultrasonography

Contrast agents are increasingly being used to characterize the vasculature in an organ of interest,to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures.We review the mechanisms of action of first,second and third generation contrast agents and their use in various endoscopic procedures in the gastrointestinal tract.Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy,assessment of depth of invasion of esophageal,gastric and gall bladder cancers and visualization of the portal venous system and esophageal varices.In addition,contrast agents can be used to differentiate pancreatic lesions.The use of color Doppler further increases the ability to diagnose and differentiate various pancreatic malignancies.The sensitivity of power Doppler sonography to depict tumor neovascularization can be increased by contrast agents.Contrast-enhanced harmonic imaging is a useful aid in identifying the tumor vasculature and studying pancreatic microperfusion.In the future,these techniques could potentially be used to quantify tumor perfusion,to assess and monitor the efficacy of antiangiogenic agents,to assist targeted drug delivery and allow molecular imaging.

Vascular complications after adult living donor liver transplantation:Evaluation with ultrasonography

Living donor liver transplantation(LDLT) has beenwidely used to treat end-stage liver disease with improvement in surgical technology and the application of new immunosuppressants. Vascular complications after liver transplantation remain a major threat to the survival of recipients. LDLT recipients are more likely to develop vascular complications because of their complex vascular reconstruction and the slender vessels. Early diagnosis and treatment are critical for the survival of graft and recipients. As a non-invasive, cost-effective and non-radioactive method with bedside availability, conventional gray-scale and Doppler ultrasonography play important roles in identifying vascular complications in the early postoperative period and during the follow-up. Recently, with the detailed vascular tracing and perfusion visualization, contrastenhanced ultrasound(CEUS) has significantly improved the diagnosis of postoperative vascular complications. This review focuses on the role of conventional grayscale ultrasound, Doppler ultrasound and CEUS for early diagnosis of vascular complications after adult LDLT.