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Byung-Boong Lee

Publications and source records attributed to Byung-Boong Lee.

13 recordsLinked to original sources
PubMed2006

Primary Budd-Chiari syndrome: outcome of endovascular management for suprahepatic venous obstruction.

OBJECTIVE: Primary Budd-Chiari syndrome (BCS) is a rare form of hepatic venous outflow obstruction at the suprahepatic inferior vena cava (IVC), the hepatic veins, or both. We assessed our 4-year experience in the management of BCS to evaluate the results of our methods of care. METHODS: We conducted a retrospective review of a nonrandomized clinical trial conducted in three teaching hospitals. Among 28 primary BCS patients, 9 remained in medical treatment only, and 19 who failed to respond to medical treatment received additional endovascular (n = 17) or surgical therapy (n = 2). Nine underwent IVC balloon angioplasty alone, 6 had angioplasty plus stents, and 2 had transjugular intrahepatic portosystemic shunts (TIPS) for hepatic vein lesions. One patient had a mesoatrial bypass; another had liver transplantation. Immediate response to the therapy was assessed with angiography and ultrasonography based on anatomic and/or hemodynamic correction or reduction of the lesion. Subsequent assessment of portal hypertension status was made with periodic clinical and laboratory evaluation (eg, ultrasonography, liver biopsy). RESULTS: Twenty-six patients had had IVC stenosis or occlusion by focal or segmental lesion. Two patients had hepatic vein outlet obstruction. There was no evidence of coagulopathy as the pathogenesis; all were related to membranous obstruction of the vena cava. Excellent immediate response to the endovascular therapy and subsequent relief of portal hypertension were achieved in 14 patients. Four patients had restenosis or progression of the residual lesion within 2 years; three responded to repeated stenting. Primary patency was 76.5%, and primary assisted patency was 94.1%. Two patients with TIPS and two with surgical therapy maintained excellent results. The medical treatment remained effective only in a limited group of 6 (21.4%) of the 28 patients. CONCLUSIONS: In BCS, both endovascular and surgical interventions provide excellent results and potentially halt liver parenchymal deterioration caused by portal hypertension. Liver transplantation remains the ultimate solution for advanced liver failure.

Adult↗
PubMed2006

Risk factors for leg length discrepancy in patients with congenital vascular malformation.

OBJECTIVES: This study was conducted to determine the clinical risk factors for the development of leg length discrepancy (LLD) in patients with congenital vascular malformation (CVM) affecting the lower extremity. METHODS: A retrospective analysis was conducted of a prospectively collected database that included 361 patients who underwent assessment of a CVM lesion from September 1994 to January 2005. We measured LLD using lower extremity scanograms of 229 patients who were suspected of having LLD on physical examination. The risk factor analysis for a clinically significant LLD (>2 cm) was performed with the variables of age, gender, features of CVM (type, extent and depth), and the deep vein status (agenesis, hypoplasia, phlebectasia) of the affected limb. Fisher's exact test and the chi(2) test were used for the univariate analysis, and a logistic regression test was performed for the multivariate analysis. Among the patients with LLD, we compared the overgrowth group and undergrowth group with the Fisher's exact test to identify differences between the two subgroups. RESULTS: The included patients were 153 males (42%) and 208 females (57%) with a mean age of 20 +/- 14 years (range, 1 to 62). There were 157 patients (43%) in the still growing age group (age <15 years) and 204 (57%) were in the finished growing age group (age >15 years). The types of CVMs included 215 venous (60%), 43 arteriovenous (12%), 46 lymphatic (13%), and 57 (16%) combined venolymphatic malformations. On the lower extremity scanogram, 26 patients (7%) had a LLD of >2 cm due to overgrowth (n = 20) or undergrowth (n = 6) of the affected limbs. The univariate analysis showed that a venolymphatic malformation (P = .003) and a whole leg CVM (P = .000) were significant risk factors for development of LLD. However, the multivariate analysis identified the whole leg CVM lesion as a single independent risk factor for LLD (P = .004; odds ratio, 6.512, 95% confidence interval, 1.788 to 23.713). On subgroup analysis, a whole leg CVM was also identified as a risk factor for overgrowth of the affected limb. In a comparison between two subgroups of LLD (overgrowth v. undergrowth), overgrowth was significantly (P = .022) more common in female than in male patients. CONCLUSIONS: As a clinical risk factor for development of LLD, the extent of the CVM lesion was a single independent risk factor regardless of the type or depth of the CVM lesion. In addition, our data suggest that overgrowth or undergrowth of the affected limb, as a cause of LLD, might be related to gender.

Adolescent↗
PubMed2005

Ethanol embolization of arteriovenous malformations: interim results.

PURPOSE: To assess retrospectively the interim results and the complications of ethanol embolization treatment of arteriovenous malformations (AVMs). MATERIALS AND METHODS: Institutional review board approval was obtained for a retrospective review of patient medical and imaging records. Informed consent was not required by the institutional review board. Written consent for the procedure was obtained from all patients after a discussion about the advantages and risks of the procedure. After a general anesthetic was administered, 40 patients (16 male, 24 female; age range, 9-53 years) with inoperable AVMs in the body and extremities underwent staged ethanol embolizations (range, 1-24; median, 3). Pulmonary artery pressure and arterial blood pressure were monitored as ethanol was injected. Ethanol embolizations (50%-100% ethanol mixed with nonionic contrast material) were performed by using transcatheter and/or direct puncture techniques. Ten patients underwent additional coil deployment during ethanol embolization. Clinical follow-up (range, 2-48 months; mean, 14.6 months; median, 12 months) was performed in all patients, and results from imaging follow-up (range, 0-48 months; mean, 8.4 months; median, 6 months) were available from the last treatment session in 28 patients. Therapeutic outcomes were established by evaluating the clinical outcome of symptoms and signs, as well as the degree of devascularization at follow-up angiography. RESULTS: One hundred seventy-five ethanol embolizations were performed in 40 patients. Sixteen (40%) of 40 patients were cured, 11 (28%) had partial remission, seven (18%) had no remission, and one (2%) experienced aggravation. Treatment failed in five patients (12%). Ethanol embolization was considered effective (cure, 16 patients; partial remission, 11 patients) in 27 patients (68%). Eleven patients will need further treatment sessions for residual AVMs. Twenty-one patients (52%) experienced complications. Twenty-seven minor complications (skin and transient peripheral nerve injuries) (27 [15%] of 175 procedures) occurred in 18 (45%) of 40 patients. All minor complications were healed with wound dressing and observation. Five major complications (five [3%] of 175 procedures) occurred in five (12%) of 40 patients, and four patients recovered completely. CONCLUSION: Ethanol embolization has the potential for cure in the management of AVMs of the body and extremities but with acceptable risk of minor and major complications.

Adolescent↗
PubMed2004

The new role of magnetic resonance imaging in the contemporary diagnosis of venous malformation: can it replace angiography?

BACKGROUND: Magnetic resonance imaging (MRI) is well accepted for the contemporary diagnosis of venous malformation (VM), providing hemodynamic and anatomic information on the lesion, including its relationship with surrounding tissues and organs. STUDY DESIGN: A total of 196 clinically suspected VM patients were reviewed retrospectively to assess the accuracy and reliability of MRI for the diagnosis of VM. Initial workup included MRI, duplex ultrasonography, and whole-body blood pool scintigraphy, along with additional transarterial lung perfusion scintigraphy and lymphoscintigraphic assessment when indicated. Phlebography or arteriography, or both, were generally reserved as a road map for the treatment. A total of 294 MRI findings for 196 patients were also compared with the matching duplex ultrasonography findings available for 178 patients and matching whole-body blood pool scintigraphy findings for 136 patients. The phlebographic findings available for 87 patients were also compared. RESULTS: Among the 196 patients with clinically suspected VM, 174 were confirmed as having VM by MRI with true-positive findings and 2 as false-positive findings by MRI (sensitivity, 98.9%; positive predictive value, 98.9%). MRI ruled out VM for 18 patients with true-negative findings, though 2 were false-negative (specificity, 90%; negative predictive value, 90.0%). Two positive and two false-negative findings of VM, made by MRI, were subsequently confirmed by angiography. Among the 87 patients for whom phlebographic findings were available, 73 were confirmed as true-positive diagnoses of VM, 1 as false-positive, 11 as true-negative, and 2 as false-negative (sensitivity, 97.3%; specificity, 91.7%; positive predictive value, 98.7%; negative predictive value, 84.6%). CONCLUSIONS: MRI is likely to modify the traditional role of angiography for the management of VM and become a new standard, at least for diagnosis. MRI also is an excellent parameter in the assessment of treatment results.

Adolescent↗
PubMed2004

Management of arteriovenous malformations: a multidisciplinary approach.

BACKGROUND: Management of arteriovenous malformations (AVMs) remains challenging because of their unpredictable behavior and high recurrence rate. A multidisciplinary approach based on a new classification scheme and improved diagnostic techniques may improve their management. The purpose of this study was to review our experience with combined embolotherapy, sclerotherapy (embolo/sclerotherapy), and surgical procedures to manage AVMs. METHODS: A total of 797 patients with congenital vascular malformations (January 1995 through December 2001) was investigated with noninvasive studies. Once an AVM was diagnosed, all underwent angiographic confirmation as a roadmap for treatment. Embolo/sclerotherapy and surgical procedures were instituted by the multidisciplinary team with periodic follow-up per protocol. Seventy-six patients with AVMs were reviewed retrospectively to assess the diagnosis and management by a multidisciplinary approach. RESULTS: Seventy-six (9.5% of all CVM) patients had AVMs, mostly infiltrating, extratruncular form (61/76). Embolo/sclerotherapy with various combinations of absolute ethanol, N-butyl cyanoacrylate (NBCA), contour particles, and coils were used in 48 patients. Sixteen patients with surgically accessible localized lesions completed preoperative embolism and sclerotherapy through 24 sessions, with subsequent surgical excision with minimal morbidity. Interim results were excellent, with no evidence of recurrence in all 16 patients with a mean follow-up of 24 months. Thirty-two patients with surgically inaccessible lesions (infiltrating) were treated with embolism and sclerotherapy alone. There were nine failures in a total of 171 sessions. Interim results with a mean of 19 months' follow-up of embolism and sclerotherapy alone were excellent in the majority (25/32) and good to fair among the rest (7/32). However, 31 complications, mostly minor (27/31), occurred in 30 sessions. Four major complications occurred, including facial nerve palsy, pulmonary embolism, deep vein thrombosis, and massive necrosis of an ear cartilage. CONCLUSIONS: Diagnosis and management of AVMs by a multidisciplinary approach that integrates surgical therapy with embolism and sclerotherapy appears to improve the results and management with limited morbidity and no recurrence during early follow-up.

Adolescent↗
PubMed2003

Clinical and functional assessment after anticoagulant therapy of acute deep vein thrombosis involving the lower limb.

We assessed the clinical status after anticoagulant therapy in acute deep vein thrombosis (DVT) involving the lower limbs. Between 1994 and 2001, 139 patients suffering from acute DVT were treated with heparin therapy followed by oral anticoagulant therapy. The coagulation factor assay was done prior to any anticoagulation therapy. The duplex scan was checked serially. The mean follow-up periods was 32 +/- 19 months. There were 32 (23.0%)cases of protein C deficiency, 12 (8.6%) cases of protein S deficiency, 13 (9.4%) cases of AT-III deficiency and 11 (7.9%) cases of abnormal plasminogen level. Fourteen cases had coagulation factor abnormalities within the family. The initial lung scan showed 29 (20.9%) cases with high, 13 (9.4%) cases with intermediate and 70 (50.4%) cases with a low probability of pulmonary embolism (PE) developing. During the follow-up periods, there were 3 cases of non-fatal PE documented with chest CT scan. The patients were divided according to the extent of the thrombus; Group I (38 cases) was limited to the infrainguinal deep vein, Group II (70 cases) extended to the iliac vein and Group III (9 cases) extended to the vena cava. Partial lysis occurred in 20/35/3 (52.6/50.0/33.3%) cases and no change in 10/24/6 (26.3/ 34.3/ 66.7%) cases in Groups I/ II/ III, respectively. Deep vein valvular reflux occurred in 15/25/5 (39.5/35.7/55.6%) cases in Groups I/ II/ III, respectively. With anticoagulation therapy, most of the thrombi remained in unresolved states and there was a high rate of deep vein valvular reflux. However, there was no serious complications which affected the patients' quality of life.

Acute Disease↗
PubMed2003

Combined extracranial and intracranial atherosclerosis in Korean patients.

OBJECTIVES: To evaluate the frequency of intracranial atherosclerosis among patients with steno-occlusive extracranial carotid artery disease and to determine if there are factors related to the combined intracranial atherosclerosis. DESIGN: Cross-sectional study. SETTING: A tertiary referral hospital. Patients We studied 142 consecutive patients who had atherosclerotic steno-occlusive lesions (defined as > or =30% narrowing of the luminal diameter or occlusion) of an extracranial carotid artery confirmed by conventional angiography. We excluded patients who had potential cardiogenic sources of embolism. Potential vascular risk factors for each patient were obtained from medical records. Main Outcome Measure We determined the location and severity of atherosclerotic lesions by conventional angiography. We compared the vascular risk factors between patients with steno-occlusive extracranial carotid artery disease alone and patients with combined intracranial atherosclerosis and extracranial carotid artery disease. RESULTS: Intracranial steno-occlusive lesions (> or =30% stenosis or occlusion) were found in 80 patients (56.3%). Of 121 patients with significant (> or =50% stenosis or occlusion) extracranial carotid artery disease, 58 (47.9%) also had significant lesions of intracranial arteries. Univariate and multivariate analyses showed that diabetes mellitus was the only significant factor associated with combined intracranial atherosclerosis in patients with extracranial carotid artery disease. CONCLUSIONS: Intracranial atherosclerosis is common in Korean patients with steno-occlusive extracranial carotid artery disease. Diabetes mellitus is associated with intracranial atherosclerosis in patients who had steno-occlusive extracranial carotid artery disease.

Aged↗
PubMed2003

Vascular clips as a landmark for sites of anastomosis.

Vascular clips can be used in bypasses at risk of future occlusion, to assist with catheter placement for radiological intervention. We explain how vascular clips can be placed as a landmark for the sites of anastomosis. After completion of the vascular anastomosis, two or three bullets of medium-sized vascular clips are clipped to the tips of the vascular suture. The sites of the vascular anastomosis are checked by plain X-rays. Finding the inlet of the anastomosis in an occluded graft can be difficult, and the marker proved helpful for introducing the guide-wire through the inlet of the site of anastomosis. The vascular clips around the popliteal anastomosis enabled us to clearly differentiate above-knee from below-knee femoropopliteal bypasses using plain X-ray postoperatively. This is a simple yet effective method of identifying the site of vascular anastomosis. Thus, we recommend using vascular clips as a landmark to aid in postoperative intervention by allowing clear identification of the level of anastomosis.

Anastomosis, Surgical↗
PubMed2003

Identification of differentially expressed mRNAs of the autologous vein graft after an arterial bypass in mongrel dogs.

PURPOSE: Intimal hyperplasia (IH) is characterized by vascular smooth muscle cell (VSMC) proliferation in the intima and subsequent accumulation of extracellular matrix. A variety of factors that might be considered as possible VSMC mitogens induce the specific gene expression of VSMC. This study was designed to identify differentially expressed mRNA by method using an mRNA differential display. METHODS: A bilateral femoropopliteal reverse saphenous vein bypass was performed on both hind limbs of mongrel dogs. At 4 and 8 weeks after the implantation, the vein bypass grafts were harvested. The total RNAs were extracted from each specimen and transcribed into the cDNAs. Amplified cDNAs using 16 sets of primers were separated on DNA sequencing gel. Differentially displayed bands were excised from the gel, cloned, and then sequenced. The sequences were compared with the National Center of Biotechnology Information nonredundant sequence database using the Basic Local Alignment Search Tool (BLAST) program. RESULTS: Forty-three bands were cloned and sequenced. A computer search revealed that 11 of them had similarities to known genes while 32 cDNAs had no similarities to any registered DNA sequence. CONCLUSIONS: We found several genes to be related to IH. Some of them had already had their function and sequence identified whereas some of them have yet to be identified. Further studies are necessary to determine the precise relationship between these genes and IH.

Anastomosis, Surgical↗
PubMed2002

Pseudoaneurysm of the abdominal aorta caused by acupuncture therapy.

Acupuncture is a major treatment modality used in Oriental medicine to control chronic pain. However, several complications have been reported, including spinal cord injury, pneumothorax, and subcutaneous pseudoaneurysm, according to the puncture sites. We report the case of a pseudoaneurysm of the abdominal aorta caused by acupuncture.

Acupuncture Therapy↗
PubMedDate not supplied

Influence of pancreatic islets on spheroid formation and functions of hepatocytes in hepatocyte-pancreatic islet spheroid culture.

Hepatotrophic stimulation of hepatocytes is necessary to preserve long-term function of hepatocytes in hepatocyte transplantation and bioartificial liver system. The main source of hepatotrophic factors in portal venous blood seems to be the pancreatic islets. It was also reported that hepatocyte spheroids, tightly packed multicellular aggregates, showed enhanced liver-specific activities and a prolonged differentiated state compared with cells that were maintained as a monolayer. On the basis of these two facts, the authors tried to form hepatocyte-pancreatic islet spheroids and to evaluate the influence of pancreatic islets on spheroid formation and functions of hepatocytes in spheroid culture. Hepatocytes and pancreatic islet cells were harvested from adult male Sprague-Dawley rats weighing 200-250 g. Hepatocytes were cultured in spinner flasks with either basic nonstimulated medium (hepatocytes only [group BH] and cocultures with islet cells [group BI]) or hormone-stimulated medium (hepatocytes only [group HH] and cocultures with islet cells [group HI]). The size and morphology of spheroids, as determined by phase-contrast microscopy, and liver-specific functions, such as albumin secretion, urea synthesis, and ammonia removal, were compared among groups. The results were as follows: the size of spheroids, 66 +/- 53.4 microm, in group BH on day 2 was smaller than in group BI (179 +/- 66.2 microm on day 2, p < 0.05). In group BI, group HH, and group HI, smooth spheroids were observed on culture day 2. However, in group BH rugged incomplete aggregates were observed on the same day. In groups with basal medium, group BI showed better results in terms of hepatocyte-specific function such as albumin secretion, urea synthesis, and ammonia removal compared with group BH on days 2 and 3 (p < 0.05). In groups with hormone-defined medium, cocultures had no impact on albumin secretion rate, urea synthetic rate, and ammonia removal rate. In conclusion, we made a new type of hepatocyte-pancreatic islet spheroid, using a rotational culture method. Pancreatic islets in a spheroid culture system stimulated hepatocyte spheroid formation and some hepatocyte-specific functions in vitro.

Animals↗