Intraoperative Doppler Ultrasonography Research Articles

An Elbow Patch Reconstruction Technique for Narrowed Remnant Portal Veins during Right Lobe Living Donor Hepatectomy: A Rescue Surgery.

Background: Treatment of established portal vein narrowing after living donor hepatectomy is challenging. We aimed to present a new approach termed the "elbow patch reconstruction technique" to correct the narrowed remnant portal vein just or late after right lobe living donor hepatectomy. Methods: Demographic and clinical data of 12 living liver donors with narrowed remnant portal veins and treated with the "elbow patch reconstruction technique" were prospectively collected and retrospectively evaluated. Anatomic variation of the portal vein was defined in accordance with the Nakamura classification; six of the living liver donors had type A, three had type B, and the remaining three had type C. In eight of the living liver donors with a narrowed remnant portal vein, diagnosis was detected by intraoperative Doppler ultrasonography and visual inspection by experienced transplant surgeons in the living donor hepatectomy procedure. In the remaining four living liver donors, diagnosis was performed postoperatively when elevation of liver enzymes was noticed during the routine liver function test and Doppler US. The diagnosis was confirmed by multidetector computed tomography. Results: Data from nine males and three females aged 18 to 54 years were analyzed. All of the living liver donors were followed up for a median of 1710 days (min-max: 1178-4447 days; IQR: 1516 days), and none of the living liver donors had any structural or functional complications in the portal vein. Conclusions: Narrowing remnant portal veins are rare, but they are a life-threatening complication in living liver donors, and this condition requires urgent management. Image guided interventions and narrowed segment resection with end-to-end anastomosis using a vascular graft carried a potential risk for thrombosis and restenosis. To avoid these complications, we shared a technique named "elbow patch reconstruction technique". This technique can be very effective in relieving the narrowing of the remnant portal vein after right lobe living donor hepatectomy.

Role of intraoperative Doppler Ultrasound in brain surgery

Role of intraoperative Doppler Ultrasound in brain surgery

Salvage Maneuvers for Occluded Bypass in Cerebral Revascularization Procedures

ObjectCerebral revascularization is an effective measure for dealing with complicated intracranial aneurysms and ischemic cerebro-vascular disease. Intra-operative thrombosis causing bypass occlusion is a severe issue that cause devastating consequences for complication in revascularization. We report our experiences regarding salvage maneuvers for intraoperative thrombosis in cerebral revascularization procedures and discuss the characteristics and culprits. MethodsWe investigated 720 consecutive patients who underwent cerebral revascularization at the First Affiliated Hospital of Soochow University from January 2013 to October 2021, including 688 patients who underwent superficial temporal artery (STA)-middle cerebral artery (MCA) bypass and 32 patients who underwent extracranial artery-radial artery (ECA-RA)-MCA bypass. Forty-one patients experienced intracranial aneurysms, and the remaining 679 patients was involved in moyamoya disease (MMD), skull base tumors, intracranial occlusive vascular diseases, or other cerebrovascular diseases. All clinical characteristics, clinical imaging examinations and neurological outcomes were studied pre- and postoperatively. The patency of bypasses was confirmed by intraoperative doppler ultrasonography and indocyanine green (ICG) videoangiography. ResultsSeven intraoperative thromboses, which were confirmed by intraoperative doppler ultrasonography and ICG videoangiography, including STA-MCA bypass (n=5) and ECA-RA-MCA bypass (n=2), were observed in 720 patients who underwent cerebral revascularization. The anastomotic stoma remained patent in 6 of 7 patients with intraoperative thrombosis after treatment. One case in STA-MCA bypass failed to be salvaged. Of the four intraoperative thrombosis in STA-MCA bypass for MMD being successfully saved, two were salvaged by applying gelfoam around the site of the anastomosis to relieve the downward compression effect of the donor vessel(STA) on the recipient vessel(M4 segment of MCA).One case in ECA-RA-MCA bypass were salvaged by thrombectomy through donor arteriotomy (radial artery) and reanastomosis. The other case was salvaged by complete reanastomosis. All seven patients who experienced intraoperative thrombosis achieved favorable outcomes at discharge and the 6-month follow-up. ConclusionVarious factors are responsible for intraoperative thrombosis in cerebral revascularization. Relieving the downward compression effect of the donor vessel STA on the recipient vessel M4 segment of MCA by applying gelfoam around the site of the anastomosis stoma, can be recommend to salvage the intraoperative thrombosis in cerebral revascularization.

Intraoperative Hemodynamics of Parasylvian Cortical Arteries for Predicting Postoperative Symptomatic Cerebral Hyperperfusion after Direct Revascularization in Patients with Moyamoya Disease: A Preliminary Study.

Objective. The search for methods by which to predict the risks of cerebral hyperperfusion syn-drome (CHS) in adults with moyamoya disease (MMD), including those utilizing new biomarkers, still deserves further research. The objective of this study was to investigate the association between the hemodynamics of parasylvian cortical arteries (PSCAs) and postoperative CHS. Methods. A consecutive number of adults with MMD who had undergone direct bypass between September 2020 and December 2022 were recruited. Intraoperative microvascular doppler ultrasonography (MDU) was performed to evaluate the hemodynamics of PSCAs. The intraoperative flow direction, mean value of velocity (MVV) of recipient artery (RA) and bypass graft were recorded. According to flow direction after bypass, RA was divided into entering sylvian (RA.ES) and leaving sylvian (RA.LS) subtypes. Univariate, multivariate, and ROC analyses of the risk factors for postoperative CHS were performed. Results. A total of 16 (15.09%) cases in 106 consecutive hemispheres (101 patients) sat-isfied the postoperative CHS criteria. According to univariate analysis, advanced Suzuki stage, MVV of RA before bypass, and fold increase of MVV in RA.ES after bypass were significantly associated with postoperative CHS (p < 0.05). Multivariate analysis indicated that left-operated hemisphere (OR (95%CI), 4.58 (1.05-19.97), p = 0.043), advanced Suzuki stage (OR (95%CI), 5.47 (1.99-15.05), p = 0.017), and fold increase of MVV in RA.ES (OR (95%CI), 1.17 (1.06-1.30), p = 0.003) were statistically significantly associated with the occurrence of CHS. The cut-off value of fold increase of MVV in RA.ES was 2.7-fold (p < 0.05). Conclusions. Left-operated hemisphere, advanced Suzuki stage, and postoperative fold increase of MVV in RA.ES were potential risk factors for postoperative CHS. Intraoperative MDU was useful for evaluating hemodynamics and predicting CHS.

Intraoperative Doppler Ultrasound for Detection of Early Postoperative Vascular Complications in Orthotopic Liver Transplants.

Liver transplantation is currently the only curative treatment for patients with end-stage liver disease. However, liver transplantation can be associated with catastrophic complications in the early postoperative setting, including hepatic artery thrombosis (HAT) and portal vein thrombosis (PVT). Postoperative complications are associated with hepatic artery resistive index (RI) < 6, systolic acceleration time (SAT) > 0.08 seconds and peak systolic velocity (PSV) > 200 cm/s on doppler ultrasound (DUS). DUS is also used in an intraoperative setting to assess patency and early complications prior to the end of the operative period, allowing for early correction. This literature review evaluates the prevalence of DUS use in intraoperative settings to identify transplant complications. A lack of consistency and minimal knowledge of intraoperative DUS warrants additional research into its usage and standardization.

Safety and Efficacy of Intraoperative Doppler Sonography-Assisted Cervical Pedicle Screw Fixation-A Retrospective Comparison with Conventional Pedicle Screw Implantation.

A Retrospective Cohort Study. To introduce a new Doppler sonography-assisted pedicle screw fixation technique that enables vertebral artery (VA) monitoring during surgery and compares the accuracies of Doppler sonography-assisted cervical pedicle screw fixation and the conventional technique. This retrospective study was performed on 164 consecutive patients that underwent pedicle-based screw fixation from C2 to C6 between January 2013 and August 2020. Surgery was performed without intraoperative Doppler sonography in 84 cases (the Control group) or with intraoperative Doppler sonography in 80 cases (the Doppler group). Proper positioning of pedicle screws was graded, and the incidences of VA injury and screw breach in the Control and Doppler groups were compared. Three hundred and ninety-nine screws were placed in the 164 patients (Doppler, 186 screws; Control, 213 screws). The percentages of well-positioned screws in the two groups were significantly different (Doppler, 97.8%; Control, 85.0%). There were two cases of VA injury in the Control group, an incidence of 2.4%, but no case in the Doppler group. Doppler sonography can be used intraoperatively to help guide the trajectory of the cervical pedicle screw insertion. It can detect the VA inside the screw trajectory and may reduce the risk of VA injury during cervical pedicle screw fixation.

McKeown esophagectomy with concomitant median arcuate ligament release in a case of esophageal cancer with celiac artery stenosis

BackgroundThe celiac artery stenosis due to compression by median arcuate ligament (MAL) has been reported in many cases of pancreaticoduodenectomy, but not in cases of esophagectomy. Recently, the celiac artery stenosis due to MAL or arteriosclerosis has been reported to be associated with the gastric tube necrosis or anastomotic leakage following Ivor–Lewis esophagectomy. Herein, we present the first reported case of esophageal cancer with celiac artery stenosis due to compression by the MAL successfully treated by McKeown esophagectomy and gastric tube reconstruction following prophylactic MAL release.Case presentationA 72-year-old female patient was referred to our department for esophagectomy. The patient had received two courses of neoadjuvant chemotherapy with 5-FU and cisplatin for T2N0M0 squamous cell carcinoma of the middle esophagus. Preoperative contrast-enhanced computed tomography (CECT) showed celiac artery stenosis due to compression by the MAL. The development of collateral arteries around the pancreatic head was observed without evidence of aneurysm formation. The patient reported no abdominal symptoms. After robot-assisted esophagectomy with mediastinal lymphadenectomy, gastric mobilization, supra-pancreatic lymphadenectomy, and preparation of the gastric tube were performed under laparotomy. Subsequently, the MAL was cut, and released to expose the celiac artery. Improved celiac artery blood flow was confirmed by decreased pulsatility index on intraoperative Doppler sonography. The operation was completed with the cervical esophagogastric anastomosis following cervical lymphadenectomy. Postoperative CECT on postoperative day 7 demonstrated increased celiac artery patency. The patient had an uncomplicated postoperative course thereafter.ConclusionsProphylactic MAL release may be considered in patients with celiac artery stenosis due to compression by the MAL on preoperative CECT for esophagectomy.

A Systematic Review and Meta-analysis of the Efficacy of Intraoperative Vascular Doppler Ultrasonography for Vein Ligations and Artery Preservations in Microsurgical Subinguinal Varicocelectomy

The gold standard of varicocele management is microsurgical subinguinal varicocelectomy. This procedure leads to better preservation of the testicular artery and lymphatic vessels. However, sometimes several vessels were in complex position causing the dissection to be more difficult. By using IVDU, more arteries and veins could be identified to acquire better sperm outcomes. It's uncertain if the Doppler Ultrasonography has a role in varicocele therapy. The goal of this systematic review and meta-analysis was to see how effective microsurgical subinguinal varicocelectomy with intraoperative vascular Doppler ultrasonography compared to without intraoperative vascular Doppler ultrasonography. Randomized Controlled Trials (RCTs), non-randomized trials, and comparative observational studies were searched and screened in the Embase, Medline, and Scopus databases for research examining the role of intraoperative Doppler ultrasonography. The Cochrane risk of bias (RoB) tool 2 was used to assess RCT bias, whereas the ROBINS-I tool was utilized to assess non-randomized trial bias. The New Ottawa Scale was used to evaluate observational research. The systematic search and screening yielded five suitable studies, including three RCTs, one non-randomized trial, and one observational research. Between patients receiving IVDU and those having the treatment without IVDU, there is a significant difference in the number of ligated veins (MD 0,94; 95 percent CI 0,62?1,26; p0,00001) and preserved arteries (MD 0,43; 95 percent CI 0,30?057; p0,00001). Patients receiving IVDU had better ligated veins and preserved arteries than patients having the surgery without IVDU.

Usefulness of intraoperative contrast-enhanced color Doppler ultrasonography for selective renal artery clamping in robot-assisted partial nephrectomy.

Usefulness of intraoperative contrast-enhanced color Doppler ultrasonography for selective renal artery clamping in robot-assisted partial nephrectomy.

Selective Angiography to Detect Anterior Spinal Artery Stenosis in Thoracic Ossification of the Posterior Longitudinal Ligament.

Study DesignSingle-center prospective study.PurposeTo investigate anterior spinal artery (ASA) status using preoperative selective angiography in patients undergoing surgery for thoracic ossification of the posterior longitudinal ligament (T-OPLL).Overview of LiteratureSurgery for T-OPLL has a high risk of neurological complications, which might be associated with insufficient spinal cord blood flow.MethodsThis study prospectively examined nine T-OPLL patients who underwent posterior thoracic decompression with kyphosis correction and instrumented fusion at Hamamatsu University School of Medicine between 2017 and 2019. All underwent preoperative selective angiography to detect and evaluate the Adamkiewicz artery and ASA. Intraoperative neuromonitoring and Doppler ultrasonography were performed to analyze neurological complications and spinal cord blood flow.ResultsAll nine patients showed ASA stenosis in the area of T-OPLL. In all patients, the Adamkiewicz artery was located between T7 and L2 and the area of ASA stenosis corresponded to the level of T-OPLL and greatest spinal cord compression; intraoperative Doppler ultrasonography confirmed the ASA defect at the same spinal level. The number of spinal levels from the Adamkiewicz artery to the most compressive OPLL lesion was greater in the two patients who developed postoperative neurological deficit compared to those who did not (5.5 vs. 2.3, p=0.014).ConclusionsThis is the first study to report detection of ASA stenosis in patients with T-OPLL. Maintaining spinal cord blood flow is important in these patients to avoid neurological deterioration.

Ultrasound Doppler examination in the surgical treatment of pituitary adenomas with cavernous sinus extension

Objective: To determine the effectiveness of intraoperative Doppler ultrasound in the surgical treatment of pituitary adenomas with invasive parasellar growth into the cavernous sinus Knosp 3 and Knosp 4. Material and Methods. During 2009–2017, 71 patients with pituitary adenomas (PA) with extension into the cavernous sinus Knosp 3 and Knosp 4 were retrospectively reviewed. According to the size PA were divided into pituitary macroadenomas, (from 10 to 40 mm) in 45 (63.4%) patients, and giant PA (over 40 mm) – in 26 (36.6%) patients. Cavernous sinus invasion Knosp 3 and 4 was identified in 47 (66.2%) and 24 (33.8%) patients respectively. Non-secreting PA - 43 (60.5%) patients and hormone-secreting PA - 28 patients (39.4%). Endoscopic endonasal trassphenoidal (EET) approach was used in all cases. Laterally expanded EET (LEEET) approach was used in 29 cases. Intraoperative Doppler ultrasound (IDUS) was used in 36 (51%) cases. Results. Intraoperative Doppler ultrasound was used in cases of Knosp 3 extension in 23 (32.4%) cases and in Knosp 4 - in 13 (18.3%) cases. Gross total resection, including extension into the cavernous sinus using IDUS was achieved in 22 (62.7%) patients. In cases where IDUS was not used, gross total resection was achieved in 19 (52.7%) cases. In cases where the IDUS was not used, recurrence rate was 7.3%, with IDUS - 5%. Biochemical remission was achieved in 22 (78.6%) cases. Liquorrhea nasalis after surgery was observed in 6 (8.4%) cases, meningoencephalitis - in 1 (1.4%) case, oculomotor palsy -3 (4.2%) cases. Conclusions. Intraoperative Doppler ultrasound is an informative method that provides safe resection of pituitary adenomas with cavernous sinus extension with a low level of possible postoperative complications. Parasellar extension of Pituitary adenomas into the cavernous sinus Knosp 4 significantly reduces the possibility of gross total resection. However, the use of intraoperative ultrasound makes it possible to determine safe boundaries for manipulation both medially and laterally from the internal carotid artery, increasing the level of radicality and the duration of clinical remission. Intraoperative Doppler ultrasound during endoscopic endonasal transsphenoidal surgery of pituitary adenomas with parasellar extension allows to identify the internal carotid artery in the tumor stroma with the existing changed skull base anatomy. Dura incision under intraoperative Doppler ultrasound reduces the risk of internal carotid artery injury.

An aberrant right hepatic artery arising from the gastroduodenal artery: a pitfall encountered during pancreaticoduodenectomy.

Among the variations of the right hepatic artery (RHA), the identification of an aberrant RHA arising from the gastroduodenal artery (GDA) is vital for avoiding damage to the RHA during surgery, since ligation of the GDA is necessary during pancreaticoduodenectomy (PD). However, this variation is not frequently reported. The purpose of this study was to focus on an aberrant RHA arising from the GDA, which was not noted in the classifications reported by Michels and Hiatt. A total of 574 patients undergoing a PD between Jan 2001 and Dec 2015 at a tertiary care hospital in Switzerland (n = 366) and between Jan 2009 and May 2015 at a hospital in Japan (n = 208) were included in the analysis. Of these, preoperative CT angiography or/and MRI angiography findings were available for 532 patients. We retrospectively analyzed the hepatic artery variations, patient demographics, and surgical outcomes. Among the 532 patients who received a PD, an RHA originating from the GDA was observed in 19 cases (3.5%). Eleven patients (2.1%) had both an aberrant RHA and an aberrant left hepatic artery (LHA) (Hiatt Type 4). Six patients (1.2%) had a replaced CHA arising from the SMA (Hiatt Type 5). We could, therefore, correctly identify the aberration in all cases. We observed rarely reported but important aberrant RHA variations arising from the GDA. To prevent injury during PD in patients with this type of aberrant RHA, intensive preparations using CT and/or MRI imaging before surgery and intraoperative liver Doppler ultrasonography are considered to be essential.

Hydroacoustic analysis and extraluminal compression surgical insights of venous pulsatile tinnitus

ObjectiveThis study aimed to quantitatively and qualitatively evaluate the hydroacoustic changes from “presence” to “disappearance” of pulsatile tinnitus (PT) with the extraluminal compression surgical technique. The recent issues of concern pertaining to the hydroacoustic characteristics of sigmoid sinus wall anomalies and distal transverse sinus stenosis (dTSS) were discussed. MethodsThis study was based on a retrospective case series. Seventy-seven patients with PT and transverse-sigmoid sinus enlargement with or without transverse-sigmoid sinus junction anomalies and transverse sinus stenosis (TSS) who had undergone extraluminal compression surgery under local anesthesia were included. Management of intractable intraoperative challenges and techniques for reversal extraluminal compression were introduced. Anatomical measurements, intraoperative color-coded Doppler ultrasonography, spectro-temporal analysis, and computational fluid dynamics were employed to analyze the hydroacoustic characteristics of PT. ResultsThe efficacy of the extraluminal compression technique was evident with the significant reduction in peak turbulent kinetic energy, vorticity, and mean pressure gradient at the transverse-sigmoid junction, resulting in over 20% reduction in PT amplitude. dTSS is a common finding in patients with PT exhibiting transverse-sigmoid sinus enlargement. Patients with dTSS presented with significant differences in hemodynamic characteristics as compared to those without. Linear regression analysis showed that the flow disturbance (turbulent kinetic energy and vorticity) was closely associated with the degree of dTSS, whereas the flow amplitude was not related to the degree or location of TSS. Low-pulsatory vortex flow at the transverse-sigmoid junction was visualized during an intraoperative color-coded Doppler examination, and the displayed low-frequency PT sound corresponded to the patients’ subjective perception of PT. Conclusion(1) A reduction of over 20% of the flow-induced noise is the therapeutic goal of extraluminal compression technique. Since reductions in the magnitude of hemodynamic parameters, including turbulent kinetic energy, vorticity, and mean pressure gradient, render the flow-induced noise inaudible, besides sigmoid sinus wall anomalies, it is likely that PT develops from the aggregation of flow-based pathologies. (2) Although dTSS and diverticulum may greatly affect the hemodynamics at the transverse-sigmoid junction, in contrast to dehiscence, dTSS and diverticulum may not be the limiting factors for PT development.

Current role of intraoperative ultrasonography in hepatectomy.

Hepatectomy had a high mortality rate in the previous decade because of inadequate techniques, intraoperative blood loss, liver function reserve misdiagnoses, and accompanying postoperative complications. However, the development of several modalities, including intraoperative ultrasonography (IOUS), has made hepatectomy safer. IOUS can provide real-time information regarding the tumor position and vascular anatomy of the portal and hepatic veins. Systematic subsegmentectomy, which leads to improved patient outcomes, can be performed by IOUS in open and laparoscopic hepatectomy. Although three-dimensional (3D) computed tomography and gadoxetic acid-enhanced magnetic resonance imaging have been widely used, IOUS and contrast-enhanced IOUS are important modalities for risk analyses and making decisions regarding resectability and operative procedures because of the vital anatomical information provided and high sensitivity for liver tumors, including "disappearing" liver metastases. Intraoperative color Doppler ultrasonography can be used to delineate the vascular anatomy and evaluate the blood flow volume and velocity in hepatectomy patients and recipients of deceased- and living-donor liver transplantation after vessel reconstruction and liver positioning. For liver surgeons, IOUS is an essential technique to perform highly curative hepatectomy safely, although recent advances have also been made in virtual modalities, such as real-time virtual sonography with 3D visualization.

Arterial reconstruction using the donor\u2019s gonadal vein in living renal transplantation with multiple renal arteries: a case report and a literature review

BackgroundArterial reconstruction is one of the paramount procedures in kidney transplantation (KT) and greatly important if the procured kidney has multiple renal arteries (MRA). Despite various established techniques for arterial reconstruction, sometimes, the surgeon finds performing arterial anastomoses challenging in case of MRA. In our case, the donor’s gonadal vein and recipient’s internal iliac artery graft were used for arterial anastomoses, and 3 years after KT, the allograft did not present vascular complications.Case presentationA 34-year-old man underwent ABO-incompatible preemptive living KT. The allograft had three renal arteries and four renal veins. After donor nephrectomy, arterial reconstruction was performed on a back table. These arteries were reconstructed into one piece using the recipient’s internal iliac artery graft. The two arteries at the middle of the renal hilum were reconstructed using the conjoined method. As the superior renal artery was too short to anastomose, the donor’s gonadal vein was used for extension. The internal iliac artery graft was anastomosed to the original internal iliac artery. Intraoperative Doppler ultrasonography revealed that the blood flow in each renal artery was adequate, resulting in sufficient blood flow throughout the allograft. The allograft function was maintained with a serum creatinine level of approximately 0.9 mg/dL without vascular complications 3 years after KT.ConclusionsThe donor’s gonadal vein can be a candidate for extension of the renal artery in the allograft with MRA. Further follow-up is needed for the assessment of long-term outcomes.

Local Cerebral Hemodynamics after Superficial Temporal Artery-Middle Cerebral Artery Bypass in Patients with Symptomatic Carotid Occlusions.

Context:Physiological insights into blood flow alterations in cortical vessels after superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery are important for the prognosis of bypass sustainability and hemodynamic patency.Aims:This study aims to assess the impact of STA-MCA bypass on local hemodynamics for patients with symptomatic carotid occlusions and Moyamoya disease.Settings and Design:This article presents a prospective nonrandomized study of intraoperative blood flow measurements in cortical branches of MCA and donor vessel before and after cerebral revascularization.Materials and Methods:Evaluation of local hemodynamic parameters was established for 112 patients with symptomatic carotid occlusive disease and cerebrovascular insufficiency during STA-MCA bypass surgery. We used intraoperative Doppler ultrasonography (89 patients – 72%), flowmetry (56 cases – 50%), and in 33 cases both methods. For physical justification of observed facts, we performed computational simulation with OpenFOAM CFD framework using Navier-Stokes nonstationary hemodynamic model.Statistical Analysis Used:All calculations were performed with IBM SPSS Statistics version 10.0 software. We used parametric (Z-test and Student's t-test) and nonparametric models (Wilcoxon, Mann–Whitney). For categorical values, we used Fisher's exact test.Results:Local cerebral hemodynamics after revascularization surgery significantly depended on initial perfusion deficit and the ability of bypass to reverse the blood flow in proximal parts of cortical artery (86 cases, 77%). Mechanism of cortical blood flow alteration was related to donor vessel cut flow value and potential consumption threshold of acceptor artery.Conclusions:Knowledge of hemodynamic principles of flow redistribution after STA-MCA bypass is important to improve bypass stainability and leads to better revascularization results.

Utility of Polyethylene Terephthalate (Dacron) Vascular Grafts for Venous Outflow Reconstruction in Living-Donor Liver Transplantations

BackgroundVenous outflow reconstruction of modified right-lobe liver grafts has been shown to prevent the occurrence of graft congestion and subsequent complications, including graft loss. In the present study, we aimed to investigate the safety and efficacy of Dacron grafts for venous reconstruction in living donor liver transplantation (LDLT). MethodsBetween January 2016 and January 2018, Dacron grafts were used in 148 liver transplants. Of these, 104 patients who had a follow-up computerized tomography (CT) scan were enrolled into the study. A total of 179 outflow hepatic veins including V5, V8, partial middle hepatic vein, and accessory inferior right hepatic veins (IRHV) were reconstructed using synthetic Dacron grafts. Graft patency was evaluated with both intraoperative Doppler ultrasonography following reconstruction, and a follow-up CT was performed on the postoperative day 7 (±1). Retrospective data collection included demographics, parameters for small-for-size (laboratory tests [bilirubin, International Normalized Ratio] and ascites) syndrome, postoperative morbidity, and mortality. ResultsFollow-up CT revealed graft patency in 155 out of 179 (86.6%) vascular grafts. Postoperative seventh-day patency rates for each reconstructed vein were as follows: V5, 87.5% (70/80); V8, 87.7% (50/57); partial middle hepatic vein, 100% (11/11); and IRHV, 77.4% (24/31). No major graft-related complications (early graft dysfunction, graft infection) or graft-related mortality were observed. None of the recipients developed small-for-size syndrome based on laboratory tests and clinical findings. ConclusionsDacron vascular grafts appear as an advantageous and useful alternative for venous outflow reconstruction in LDLT.

Utility of Doppler Ultrasonography in Liver Transplantation With Celiac Axis Compression Syndrome: A Case Report

BackgroundCeliac axis compression syndrome (CACS) blocks adequate hepatic arterial flow and is a risk factor for hepatic artery thrombosis after liver transplantation. We report a case of living donor liver transplantation in a 65-year-old Brazilian male with liver cirrhosis of Child-Pugh class C and hepatocellular carcinoma caused by hepatitis C virus infection. ResultsThe patient underwent living donor liver transplantation using the graft of his 34-year-old daughter. Stenosis of the celiac artery was detected on preoperative computed tomography (CT), and CACS was suspected. Maintaining blood supply through the hepatic artery to prevent potential graft loss is essential in liver transplantation. A decrease in common hepatic artery (CHA) flow due to CACS could disturb graft blood supply or lead to hepatic artery thrombosis. In this case, we confirmed CACS through dynamic CT and used intraoperative Doppler ultrasonography (US) to plan the surgical procedure. Three types of hepatic artery reconstruction have been described in liver transplantation for CACS, namely the release of the median arcuate ligament (MAL), aorto-hepatic graft reconstructions, and reconstruction preserving the gastroduodenal artery (GDA) without MAL release. We found that clamping the GDA completely abolished hepatic inflow, but clamping the CHA did not change the hepatic inflow. Therefore, we performed arterial reconstruction without division of the GDA. The patient's postoperative course was good, with excellent hepatic artery flow, as assessed by Doppler US. ConclusionsPreoperative dynamic CT evaluation, adequate preparation of surgical procedures, and intraoperative evaluation by Doppler US is recommended in liver transplantation patients with CACS.

Near-infrared image-guided laparoscopic omental flap for breast cancer.

Near-infrared (NIR) imaging with indocyanine green (ICG)-enhanced fluorescence is widely used in laparoscopic surgery. This study aimed to evaluate this technique's feasibility and usefulness in intraoperatively assessing vascular perfusion in a laparoscopically harvested omental flap. From March 2015 to February 2016, we prospectively evaluated patients undergoing breast cancer surgery followed by immediate breast reconstruction using a laparoscopically harvested omental flap. After laparoscopic preparation of the pedicled graft, the perfusion area of the omental graft was evaluated by using intraoperative Doppler ultrasonography and NIR imaging with intravenous ICG injection. Graft viability was evaluated by using Doppler ultrasonography 2 days postoperatively; for cosmetic outcome, Breast Cancer Conservative Treatment Cosmetic Results software was used 1 month postoperatively. The laparoscopic harvesting of an omental flap was successfully performed in eight patients without conversion to open surgery. The mean time to the initial detection of ICG-enhanced fluorescence uptake was 3.25 ± 1.16 minutes. On intraoperative Doppler ultrasonography, a pulseless area ≥10% was detected in five patients (62.5%). However, NIR imaging revealed no patients had an ischemic portion ≥10%. There were no ICG-related intraoperative or postoperative complications. All patients showed patent vessels on Doppler ultrasonography 2 days postoperatively. Cosmetic outcomes were mostly favorable 1 month postoperatively. The Breast Cancer Conservative Treatment Cosmetic Results evaluation 1 month postoperatively showed excellent, good, and fair results, with no poor scores. With regard to vascular perfusion, ICG-enhanced NIR imaging is a feasible and useful tool for harvesting a laparoscopic omental flap in breast cancer patients.

Intraoperative Doppler ultrasound of the cavernous part of the internal carotid artery in endoscopic transsphenoidal removal of the laterosellar tumors

The study objective is to describe the technique of intraoperative Doppler ultrasound (DU) of brain arteries and to determine the indications for its use during endoscopic transsphenoidal operations. Materials and methods. The study included 100 patients with skull base tumors (pituitary adenomas, trigeminal schwannomas, chordomas), operated via standard or extended transsphenoid endoscopic approaches. For DU, the location of the internal carotid artery (ICA) relative to the surface of the tumor or dura mater was determined as a red and/or blue color of the monitor screen in the M-mode window, accompanied by a characteristic sound signal. Results. DU was used to remove pituitary adenomas in 95 cases, trigeminal schwannomas in 3 cases, chordomas in 2 cases. Intraoperative DU helped to locate the ICA during removal of the laterosellar part of the tumor in all observations. In none of the cases presented were no injuries to the ICA. Сonclusion. DU is an effective and non-invasive method for detecting ICA during endoscopic operations which contributes to the safe disposal of laterosellar tumors. Adequate use of the method does not carry well-known and potential risks. DU should be performed when the tumor is removed from the cavernous sinus or its projection via the lateral extended transsphenoidal endoscopic access (to determine the safe boundaries of the dura mater section in the cavernous sinus projection).