Search

Purpose: To evaluate the safety and efficacy of additional aspiration thrombectomy (AT) or pharmacomechanical thrombectomy (PMT) after catheter-directed thrombolysis (CDT) for the treatment of acute iliofemoral deep vein thrombosis (AIFDVT). Materials and Methods : : Between May 2017 and December 2018, 40 patients with AIFDVT were enrolled. Twenty underwent AT after CDT (CDTAT), while the remaining 20 underwent PMT using an AngioJetTM device after CDT (CDTPMT). Thrombus clearance was assessed using computed tomography venography at 1 week after the procedure, as follows: grade I, ≤50%; grade II, 51% to 75%; grade III, >75%. Grade III was considered a successful outcome. Treatment outcomes (thrombus clearance, thrombolytic therapy duration, urokinase dose, major complications, residual filter thrombosis, and Villalta score) were compared between the groups. Results : : Successful thrombus clearance was achieved in 95% of the patients in both groups. Significant decreases in the thrombolytic therapy duration (P=0.018) and urokinase dose (P=0.014) were noted in the CDTPMT group. Major complications were not noted in both groups. Residual filter thrombi >10 mm were found in 6 filters in the CDTAT group and in 1 filter in the CDTPMT group (P=0.038). The Villalta scores at 6 months were 1.47±1.24 and 1.12±0.92 in the CDTAT and CDTPMT groups, respectively (P=0.372). Conclusion : : Both methods may be safe and effective management options for patients with AIFDVT. CDTPMT can reduce urokinase dosage, time and remained filter thrombus compared to CDTAT. Studies conducted in the future should compare the effects of overnight CDT followed by PMT with those of single-session PMT on patients with AIFDVT.

The use of retrievable inferior vena cava (IVC) filters has markedly increased in the recent years. However, the failure rate for the retrieval of the IVC filters using the endovascular method is reported to be up to 19%. Open surgical removal of the IVC filters is technically challenging and may require longitudinal cavotomy, clamping, and repair of the IVC. Here, we present a case of successful open surgical removal of the IVC filter using minimal cavotomy. This technique is an effective method after a failed endovascular removal attempt.

The treatment of varicose veins has shifted from conventional surgical stripping (SS) to minimally invasive endovenous modalities. Cyanoacrylate closure (CAC) with the VenaSeal system (Medtronic, Dublin, Ireland) has increased in popularity owing to its nonthermal and nontumescent technique. The purpose of the present study was to compare the clinical outcomes of CAC and SS for the treatment of incompetent great saphenous veins.An open-label, multicenter, prospective, randomized controlled trial was conducted. The subjects were randomized to either the CAC or SS procedure. The primary endpoint of the present study was to evaluate complete closure of the target vein at 3 months. Target vein occlusion was assessed on the third day and 1, 3, 6, and 12 months postoperatively using duplex ultrasound. The pain and ecchymosis grades were also assessed. Additionally, the clinical outcomes, such as the venous clinical severity score and Aberdeen Varicose Vein Questionnaire score, were assessed.Three-month follow-up data were obtained for all 126 enrolled and randomized subjects (63 with CAC and 63 with SS). At 3 months, complete target vein closure was observed in both groups. The postoperative pain score was significantly better in the CAC group than in the SS group (0.3 ± 0.6 in the CAC group and 1.1 ± 1.5 in the SS group; P .001). In addition, the mean ecchymosis grade was 0.3 ± 0.5 in the CAC group and 1.1 ± 1.1 in the SS group (P .001). The venous clinical severity score and quality of life had improved equally in both groups. The adverse events after both procedures were mostly minor complications (9 events in CAC group and 20 events in SS group). Major complications occurred in one patient who had undergone the SS procedure.The CAC and SS procedures were both associated with complete occlusion of the target vein at 3 months. The postoperative pain and ecchymosis grades were significantly lower in the CAC group. Other differences between the two groups included the frequency and nature of the complications. The results showed that CAC has high success with few complications.

Abstract. Background: Endovascular treatment is an alternative first-line management for peripheral artery disease (PAD). Hybrid treatment (HT) is defined as a combined treatment for patients with PAD using endovascular and open surgery, simultaneously performed in an operating room. The results of HT are reportedly good for multilevel revascularization (MR) in patients with chronic limb ischaemia, and even in older high-risk patients. The goal of this study was to examine the clinical and haemodynamic outcomes of HT in patients who need MR. Patients and methods: Nine university hospitals in Korea participated in this multicentre study. A total of 134 patients with multilevel PAD underwent HT and MR. Patients were enrolled from July 2014 to June 2015 and were followed for 18 months. Results: The mean age of the patients was 68.8 ± 9.93 years and 88.1 % were men. Patients with Rutherford category 2 to 3 and 4 to 6 comprised 59.0 % and 42.0 % of the group, respectively. The technical success rate was 100 %. The primary patency rates at 12 and 18 months were 77.6 % and 63.9 %, respectively. The primary-assisted patency rates at 12 and 18 months were both 90.0 %. The pre-operative mean ankle brachial index (0.43 ± 0.23) increased to 0.87 ± 0.23 at six months post-operatively (t-test, p < 0.05). The amputation free survival rate was 97.1 %. Conclusions: Although outcomes of multilevel PAD are reportedly poor when endovascular treatment alone is used, we have shown that HT is a feasible alternative modality for patients with multilevel PAD, with satisfactory amputation-free survival and freedom from re-intervention rates.

The small saphenous vein (SSV) is an important graft in limb salvage surgery. It is frequently translocated for bypass surgery. Sometimes, the use of the SSV as an in-situ graft for posterior tibial artery or peroneal artery reconstruction offers the advantages of reduced vein graft injury and improved patency. Recently, saphenous vein mapping through computed tomography (CT) volume rendering technique offers a great quality view to the surgeon. We experienced a patient in whom a CT image with volume rendering technique revealed an aberrant SSV connected with the great saphenous vein at the medial malleolus level. This case indicates that an aberrant SSV may be successfully used as an in-situ conduit for bypass to the dorsalis pedis artery. Here, we present the case of a popliteal-to-dorsalis pedis in-situ vein bypass using a LeMaitre valvulotome (LeMaitre Vascular Inc., USA) under mapping of the aberrant SSV by CT volume rendering technique.

Neuronal cell death caused by oxidative stress is common in a variety of neural diseases and can be investigated in detail in cultured HT22 neuronal cells, where the amino acid glutamate at high concentrations causes glutathione depletion by inhibition of the glutamate/cystine antiporter system, intracellular accumulation of reactive oxygen species (ROS) and eventually oxidative stress-induced neuronal cell death. Using this paradigm, we have previously reported that resveratrol (3,5,4'-trans-trihydroxystilbene) protects HT22 neuronal cells from glutamate-induced oxidative stress by inducing heme oxygenase (HO)-1 expression. Piceatannol (3,5,4',3'-trans-trihydroxystilbene), which is a hydroxylated resveratrol analog and one of the resveratrol metabolites, is estimated to exert neuroprotective effect similar to that of resveratrol. The aim of this study, thus, is to determine whether piceatannol, similarly to resveratrol, would protect HT22 neuronal cells from glutamate-induced oxidative stress. Glutamate at high concentrations induced neuronal cell death and ROS formation. Piceatannol reduced glutamate-induced cell death and ROS formation. The observed cytoprotective effect was much higher when HT22 neuronal cells were pretreated with piceatannol for 6 or 12 h prior to glutamate treatment than when pretreated for 0.5 h. Piceatannol also increased HO-1 expression and HO activity via its activation of nuclear factor-E2-related factor 2 (Nrf2). Interestingly, neuroprotective effect of piceatannol was partly (but not completely) abolished by either down-regulation of HO-1 expression or blockage of HO-1 activity. Taken together, our results suggest that piceatannol, similar to resveratrol, is capable of protecting HT22 neuronal cells against glutamate-induced cell death, at least in part, by inducing Nrf2-dependent HO-1 expression.

Micro-computed tomography (CT) is a important tool for longitudinal imaging of tumor development. The detection and monitoring of tumors in the liver in live animals using micro-CT is challenging. We evaluated the feasibility of high-resolution micro-CT enhanced with a hepatocyte-selective contrast agent for detecting liver metastases in a live murine model.Hepatic metastases were induced in 10 BALB/C mice. Two mice each were randomly selected on days 3, 5, 7, 10, and 13 after CT26 colon adenocarcinoma cells were injected into the portal vein; micro-CT imaging was performed at 10 minutes and 4 hours after intravenous administration of a hepatocyte-selective contrast agent at a dose of 0.4 mL/mouse. The attenuation values of the normal liver and the tumors were obtained. The number of metastases was counted and their sizes were measured on the micro-CT images. Gross or histopathologic evaluation was performed for correlating the liver tumors with the micro-CT images.A total of 74 separate tumor sites larger than 300 microm in diameter were detected on pathologic examination of the mice that were sacrificed 7 days after cell injection. On micro-CT, 66 of 74 tumors were detected (83.8%). The smallest tumor detected on micro-CT was 300 microm. There were eight false-negative readings on micro-CT. The sizes of the individual liver metastases measured by micro-CT and on the excised specimen were highly correlated (P.001). The correlation between the CT scan measurement and the actual measurement was r = 0.8354 (P.0001).High-resolution micro-CT enhanced with a hepatocyte-selective contrast agent can be a promising tool for detecting liver metastases in a live murine model.

Purpose To introduce a nation-based endovascular aneurysm repair (EVAR) registry in South Korea and to analyze the anatomical features and early clinical outcomes of abdominal aortic aneurysms (AAA) in patients who underwent EVAR. Materials and methods The Korean EVAR registry (KER) was a template-based online registry developed and established in 2009. The KER recruited 389 patients who underwent EVAR from 13 medical centers in South Korea from January 2010 to June 2010. We retrospectively reviewed the anatomic features and 30-day clinical outcomes. Results Initial deployment without open conversion was achieved in all cases and procedure-related 30-day mortality rate was 1.9%. Anatomic features showed the following variables: proximal aortic neck angle 48.8±25.7° (mean±standard deviation), vertical neck length 35.0±17.2 mm, aneurysmal sac diameter 57.2±14.2 mm, common iliac artery (CIA) involvement in 218 (56.3%) patients, and median right CIA length 34.9 mm. Two hundred and nineteen (56.3%) patients showed neck calcification, 98 patients (25.2%) had neck thrombus, and the inferior mesenteric arteries of 91 patients (23.4%) were occluded. Conclusion Anatomical features of AAA in patients from the KER were characterized as having angulated proximal neck, tortuous iliac artery, and a higher rate of CIA involvement. Long-term follow-up and ongoing studies are required.

Primary dissection of the renal artery is rare. Spontaneous renal artery dissection can be associated with diseases such as medial degeneration, neurofibromatosis, syphilitic arteritis, tuberculosis, polyarteritis nodosa, Marfan syndrome, fibromuscular dysplasia, or Ehlers-Danlos syndrome (EDS). Among these causes, EDS re- lated renal artery dissection is very rare worldwide and has not been previously reported in Korea. EDS are a group of heritable connective tissue disorders characterized by fragility of the skin and hypermobility of the joints. We describe the case history of a young man who presented with left side flank pain, hyper- mobility of the hand joints and showed left renal artery dissection on computed tomography and angiography that turned out to be the first complication of vascular type EDS.

AMP-activated protein kinase (AMPK), a crucial regulator of energy metabolic homeostasis, is suggested to regulate inflammatory responses, but its precise mechanisms are not fully understood. It has been reported that pharmacological activation of AMPK induces heme oxygenase-1 (HO-1) expression. β-Lapachone (BL), a well-known substrate of NAD(P)H:quinone oxidoreductase (NQO1), has been demonstrated to stimulate AMPK activation via NQO1 activation, and to exert anti-inflammatory effects in macrophages. Here we examined whether AMPK activation by BL would be linked to HO-1 expression in RAW264.7 macrophages and whether HO-1 expression could mediate the anti-inflammatory effects of BL. BL treatment induced concentration- and time-dependent AMPK phosphorylation and HO-1 expression. 5-Aminoimidazole-4-carboxamide-1-β-D-ribofuranoside, an AMPK activator, also induced HO-1 expression. In contrast, compound C (CC), an inhibitor of AMPK activation, prevented the increase in BL-induced HO-1 expression. BL pretreatment reduced lipopolysaccharide-induced production of tumor necrosis factor-α, a pro-inflammatory cytokine, and expression of inducible nitric oxide synthase, a pro-inflammatory enzyme. These inhibitory effects BL were almost completely abolished by CC and partly by tin protoporphyrin-IX, a competitive inhibitor of HO-1. Accordingly, the present results indicate that BL induces anti-inflammatory HO-1 expression in macrophages via AMPK activation, providing one of possible mechanisms by which BL can exert anti-inflammatory effects.

Rationale and Objectives This study was designed to demonstrate the feasibility of the use of phase-contrast computed tomographic (CT) imaging for the identification of articular cartilage abnormalities of the knees in a mouse model of collagen-induced arthritis. Materials and Methods Arthritis was induced in nine male DBA/1 J mice by the intradermal injection of collagen. After 50 days, the nine mice were sacrificed, along with four mice that did not receive intradermal injections of collagen. Phase-contrast CT imaging using a microfocus x-ray source of the entire knee was performed. The images were evaluated by two blinded readers, and histopathologic grades were considered the reference standard. The phase-contrast CT images of cartilage were graded 0, I, or II. Evaluation of the grading agreement between the phase-contrast CT images and histopathologic findings was performed using correlation analysis. Results Phase-contrast CT images highly reflected the subchondral bone status in the assessment of articular cartilage abnormalities in the mouse model of collagen-induced arthritis. Three-dimensional reformed images showed the articular surface and subchondral bony status of the knee joints. On the basis of the histopathology of the 26 knee joints, 12 joints were grade 0, six joints were grade I, and eight joints were grade II. Grading agreement between the use of the phase-contrast CT images and histopathologic results was high (r = 0.76). Conclusions Phase-contrast CT imaging using a microfocus x-ray source offers a promising tool for the assessment of articular cartilage abnormalities of the knees in a mouse model.

To present the pharmacokinetics and computed tomographic imaging efficacy of colloidal gold nanoparticles (AuNPs) as a blood-pool agent for x-ray computed tomography (CT).To prepare the colloidal AuNPs, gold nanocrystals were modified using sulfhydrated polyethylene glycol (PEG). Cytotoxicity and histopathologic tests were carried out for toxicity evaluation. Six adult Balb/c mice underwent microcomputed tomography scans after injection of colloidal AuNPs (2.5 micromol Au/g body weight). Four mice with HT-1080 tumors were imaged for visualization of the tumor vasculature.The PEG coated colloidal AuNPs appeared as spherical nanoparticles with 38-nm diameters. The AuNPs-PEG showed a biocompatibility without toxicity in the mice. We identified a stable imaging window for visualizing the vasculature system, immediately to 24 hours after injection. Microcomputed tomography imaging using AuNPs-PEG clearly visualized the tumor vascular structures.Colloidal AuNPs show potential as a blood-pool agent for x-ray CT imaging.

The present study examined the effects of cartilage oligometric matrix protein angiopoietin-1 (COMP-Ang1) on the revascularization of mice skin grafts. Full-thickness skin grafts were autotransferred into BALB/c mice. The donor grafts were soaked in COMP-Ang1 protein (50 mug/ml, n = 10) or in bovine serum albumin (BSA) (50 mug/ml, n = 10) dissolved in 1 ml of sterile, phosphate-buffered saline for 5 minutes before transfer. Revascularization of the grafts was monitored using an intravital microscope on postoperative days 3, 4, and 5. Morphological and immunohistochemical analyses were performed to evaluate platelet-endothelial cell adhesion molecule-1 and survivin expression and apoptotic signal in the transplanted grafts. Grafts soaked in COMP-Ang1 (COMP-Ang1 group) showed significantly increased revascularization compared with grafts soaked in BSA (BSA group) on intravital microscopy and platelet-endothelial cell adhesion molecule-1 staining. The COMP-Ang1 group showed a significant increase of survivin expression in the endothelial cells and a reduction of apoptotic signal in comparison to the BSA group. Therefore, we believe that COMP-Ang1 provides the therapeutic benefit of enhancing the survival of vascular endothelial cells during transplantation of skin graft.

Objective To evaluate whether suppression of tumor microvasculature by double anti-angiogenic protein (DAAP) treatment could increase the extent of radiofrequency ablation (RFA)-induced coagulation in a murine renal cell carcinoma model. Materials and Methods Renal cell carcinoma cell lines were implanted subcutaneously into 10 nude mice. Four mice received adenoviral DAAP treatment and 6 mice received sterile 0.9% saline solution as DAAP-untreated group. The effect of DAAP was evaluated according to the vascularity by contrast-enhanced ultrasound (CEUS) using microbubbles. Four DAAP-treated mice and 4 DAAP-untreated mice were then treated with RFA, resulting in 3 groups: no-therapy (n = 2), RFA only (n = 4), and RFA combined with DAAP treatment (n = 4). Immediately after RFA, the size of coagulation necrosis and mitochondrial enzyme activity were compared between the groups using analysis of variance (ANOVA) and post hoc test. Results The contrast enhancement ratio for tumor vascularization on CEUS was significantly lower in the DAAP treated group than in DAAP-untreated group (30.2 ± 9.9% vs. 77.4 ± 17.3%; p = 0.021). After RFA, the mean coagulation diameter was 0 mm for no-therapy group, 6.7 ± 0.7 mm for the RFA only group and 8.5 ± 0.4 mm for the RFA with DAAP group (ANOVA, p < 0.001). The area of viable mitochondria within the tumor was 27.9 ± 3.9% in no-therapy group, 10.3 ± 4.5% in the RFA only group, and 2.1 ± 0.7% in the RFA with DAAP group (ANOVA, p < 0.001). Conclusion Our results suggest the potential value of combining RFA with anti-angiogenic therapy.

Purpose: The purpose of this retrospective study was to evaluate the short- to mid-term results of thoracic endovascular aortic repair (TEVAR) in Wonkwang University School of Medicine & Hospital. Methods: Between February 2009 and May 2011, 8 consecutive patients had undergone endovascular stent-grafting for thoracic aortic diseases. Five patients were treated for traumatic thoracic aortic injuries, two patients were treated for thoracic aneurysms and one patient was treated for a pseudoaneurysm due to penetrating aortic ulcers. Attempted stent-graft deployment was performed electively in 6 patients and emergently in 2. Follow-up was performed at 1-month, 6-month, 1-year, and annually thereafter. Results: Technical success rates were achieved in 87.5% and the 30-day mortality rate was 0%. Mean hospital length of stay after TEVAR was 30 days in traumatic thoracic aortic injuries and 10 days in thoracic aneurismal diseases. Intra-operative Type I endoleak due to migration at deflation was visualized in 1 patient, which was treated by insertion of another stent-graft. During follow-up, a major complication was encountered in one patient who received carotid-subclavian bypass to relieve left arm ischemia. After 5 months he was treated with arch replacement for aortic arch aneurysm with type I endoleak at proximal site after endovascular treatment. The 30-day mortality rate was 0%. However, 1 case of mortality (12.5%) was observed during the follow-up period. Conclusion: The short and mid-term results of endovascular repair of thoracic aortic diseases are promising. TEVAR is an effective procedure in the management of thoracic aortic diseases.

To report a case of acute superior mesenteric artery (SMA) embolism successfully treated with aspiration and pharmacological thrombolysis. A 74-year-old female was admitted to the hospital with acute abdominal pain 5 hours in duration. Computed tomography angiography revealed a complete embolic occlusion distal to the first jejunal branch of the SMA. Aspiration and local continuous thrombolysis with urokinase resulted in near complete revascularization of the mesenteric flow after 4 hours and almost complete restoration after 20 hours. The patient made a complete recovery and continues to do well on warfarin therapy after treatment. Aspiration and thrombolytic therapy can be an alternative treatment modality in surgical high risk patient.

Focal aneurysmal change after spontaneous superior mesenteric artery (SMA) dissection has been reported rarely. A stent graft implantation can exclude false lumen and possibly make major abdominal operation avoidable. A 52-year-old male patient was admitted due to abdominal pain for 10 days. A CT scan showed severe narrowing of the true lumen of SMA, approximately a 7 ㎝ segment from the origin, due to compression by the thrombosed false lumen. Five days after admission, abdominal pain aggravated progressively. The follow-up CT revealed focal aneurysmal dilatation of the dissected SMA segment. I report here an endovascular treatment with stent graft implantation for a focal aneurysmal change after SMA dissection.

Advances in chemotherapy and radiation therapies for malignant tumors have resulted in the identifications of various novel features of intestinal metastasis. The common causes of small bowel metastasis are malignant melanoma and lung cancer, and this has also been rarely reported to uterine cervical cancer, malignant lymphoma of the larynx, malignant lymphoma of soft palate, and hepatocellular carcinoma (HCC). The Combined HCC cholangiocarcinoma (HCC-CC) is a rare primary liver malignancy, and is composed of cells with the histopathological features of both HCC and CC, but metastatic small bowel perforation by CC in a patient with combined HCC-CC has not been reported previously. The authors describe the case of a 51-year-old man with a metastatic small bowel perforation caused by an intrahepatic CC in combined HCC-CC with a review of the literature.

Purpose: Which graft material is appropriate for the above-knee femoropopliteal (AK fem-pop) bypass has been a controversy. We were to evaluate the usefulness of PTFE graft in AK fem-pop bypass by comparing the results of autogenous vein graft in below-knee femoropopliteal bypass. Methods: This was a retrospective study of data for Fem-Pop bypass from August 1999 to August 2008. The median follow-up was 59.9±27.3 months. The demographic data, patency rate, secondary procedures, and amputation rate were compared, and statistical comparison was performed by Kaplan-Meier method, Log-rank test, and Chi-square test. Results: Seventy-three bypasses were performed in 63 patients: PTFE graft in 48 cases (Group A), autogenous vein in 25 cases (Group B). Sixty-one patients (96.81%) were men. The mean age was 67.3±8.0 years. The indication for surgery was intermittent claudication in 27 cases (37.0%), critical limb in 46 cases (63.0%). The 6-yr primary patency rates were 28.1%; 60.3%, the 6-yr secondary patency rates were 37.2±8.4%, 67.0±14.7% in Group A and Group B, respectively (P＜0.05). The number of secondary procedures was 31 and 3, respectively (P＜0.05). Major amputation at later periods was not needed in Group B, but there were 9 cases in group A (P＜0.05). Conclusion: PTFE graft for above-knee femoropopliteal bypass shows poor long-term patency with a large number of secondary procedures and a higher amputation rate than vein graft in BK Fem-Pop bypass. PTFE graft should be limited to patients with high operative risk, or poor venous graft.

†‡ § ∥ † , ‡ § ∥ Background: Opioid tolerance may involve activation of the N-methyl-D-aspartate (NMDA) system. The possible involvement of the NMDA system suggests that one of the NMDA receptor antagonists, magnesium may be a useful adjunct to opioids for the treatment of postoperative pain following remifentanil infusion. Methods: For this study, 70 patients scheduled for major abdominal surgery under remifentanil-based anesthesia were randomly allocated into groups that received either magnesium sulfate (group M) or saline (group C) intravenously. The patients in the group M received 25% magnesium sulfate at a dose of 50 mg/kg in 100 ml of saline, and those in the group C received an equal volume of saline prior to the induction of anesthesia. In addition, patients in both groups received 10 mg/kg/h infusion of either magnesium sulfate (group M) or an equal volume of saline (group C) until the end of surgery. Pain was assessed using a visual analog scale at 30 min, and 6, 12, 24, and 36 hours after operation. The time to the first use of postoperative analgesic and cumulative analgesic consumption in both groups were also evaluated. Results: The visual analog scale scores for pain and cumulative analgesic consumption were significantly lower in the group M than in the group C. The time to the first use of postoperative analgesic was significantly shorter in group C than in the group M. Conclusions: Use of the NMDA-receptor antagonist, magnesium sulfate as an adjuvant analgesic reduced postoperative pain in patients undergoing major abdominal surgery under remifentanil-based anesthesia. (Korean J Anesthesiol 2008; 55: 286∼90)

Background: Early oral intake (EOI) associated with early recovery of normal bowel function has been shown to be an important determinant for improving patients' satisfaction. We investigated the tolerability of EOI and its effects on the recovery of bowel function after epidural anesthesia. Methods: A prospective randomized trial of patients undergoing lower extremities surgery under epidural anesthesia was performed. A liquid drink was given to 150 patients in the EOI group 1 hours after surgery, and to 150 patients in the delayed oral intake (DOI) group 8 hours after surgery. We recorded presence of bowel sounds immediately after operation, symptoms of ileus, time to the first flatus, time to the first defecation, degree of appetite before the first meal, and patients' satisfaction. Results: There was no significant difference in the presence of immediate postoperative bowel sounds, the degree of appetite before the first meal, mild ileus, and severe ileus between groups. Time to the first flatus and time to the first defecation in the EOI group were shorter than those of the DOI group. The patients' satisfaction in the EOI group was higher than that of the DOI group. Conclusions: For uncomplicated patients undergoing lower extremities under epidural anesthesia, beginning oral hydration as early as 1 hour after the operation is safe and well tolerated and resulting in faster recovery of bowel function and higher patients' satisfaction. (Korean J Anesthesiol 2008; 55: 282~5)

Purpose: To develop optimal microbubble contrast agents (MBCAs) for performing ultrasound microscopy when examining small animals. Materials and Methods: We prepared three types of MBCAs. First, a mixture of three parts of 40% dextran and one part of 5% human serum albumin were sonicated with perfluorocarbon (PFC) (MB1-D40A5P). Second, three parts of 40% dextran and one part of 1% human serum albumin were sonicated with PFC (MB2-D40A1P). Third, all parts of 1% bovine serum albumin were sonicated with PFC (MB3-A1P). We measured the microbubbles' sizes and concentrations with using image analysis software. The acoustic properties of the microbubbles were assessed both in vitro and in vivo. Results: The majority of the MB1-D40A5Ps had a diameter of 2-5 μm, the mean diameter of the MB2-D40A1Ps was 2.5 μm, and the mean diameter of the MB3-A1Ps was less than 2.0 μm. Among the microbubbles, the MB1-D40A5Ps and MB2-D40A1Ps showed increased echogenicity in the abdominal vessels, but the duration of their contrast effect was less than 30 sec. On the contrary, the MB3-A1Ps exhibited strong enhancement in the vessels and their duration was greater than 120 sec. Conclusion: A microbubble contrast agent consisting of all parts of 1% serum albumin sonicated with PFC is an effective contrast agent for ultrasound microscopy.