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• Investigation of the relationship between greenhouse gas emissions and Tobin's q. • Contrasting market reaction to the changes in GHG emissions by B2B and B2C firms. • The B2B firm's environmental efforts are regarded just as costs by the market. • The B2C firms' efforts to reduce GHG emissions are rewarded by the market. • More stringent regulatory pressure is required in B2B firms to reduce GHG emissions. This paper analyzes the relationship between greenhouse gas (GHG) emissions and the financial performance of business-to-business (B2B) or business-to-consumer (B2C) organizations. We find that Tobin's q is positively associated with higher GHG emissions for B2B firms, implying that GHG emissions reduction is regarded as a necessary cost. Meanwhile, a negative relationship is found for B2C firms, which may be due to consumers responding to climate change issues. These findings contribute to our understanding of the heterogeneous relationship in the existing literature. The evidence also implies on the policy level that more stringent regulatory pressure may be required for B2B firms to reduce their GHG emissions. [ABSTRACT FROM AUTHOR]

Percutaneous vertebroplasty is a widely used treatment for vertebral compression fracture. It is relatively safe, but it can be complicated by pulmonary or cerebral embolism caused by the cement injected during the procedure. Here, we present a case of a 69-year-old male with extensive deep vein thrombosis from the inferior vena cava to the right iliac and left femoral veins, which occurred 10 months after vertebroplasty. He was treated successfully by catheter-directed thrombolysis, angioplasty, and stenting. To the best of our knowledge, this is the first report of the successful treatment of delayed thrombosis caused by migrated cement inside the inferior vena cava. [ABSTRACT FROM AUTHOR]

Objectives: There are few long-term follow-up studies about the result of revascularization surgery for the treatment of popliteal artery entrapment syndrome (PAES). We performed this retrospective study to analyze the long-term result of revascularization surgery in patients with advanced PAES during the last 16 years. Methods: Twenty-two limbs in 18 consecutive patients with PAES were treated surgically at Seoul National University Hospital between January 1994 and December 2009. The preoperative diagnosis of PAES was made by duplex ultrasonography, three-dimensional computed tomography angiography, magnetic resonance imaging, or conventional angiography. The method of surgical approach was determined by the extent of arterial occlusion in preoperative images. Results: The mean age was 31 years old and the majority of patients were men (94%). The chief complaints were claudication in 18 limbs, ischemic rest pain in three limbs, and toe necrosis in one limb. All 22 limbs underwent revascularization for advanced PAES with segmental arterial occlusion. Fourteen limbs underwent musculotendinous section and popliteo-popliteal interposition graft (13 posterior approaches, one medial approach), five femoropopliteal (below-knee) bypasses, one femoro-posterior tibial bypass, and two popliteo-posterior tibial bypasses. All revascularization surgeries were performed with reversed saphenous veins. The overall primary graft patency rates at 1, 3, and 5 years were 80.9%, 74.6%, and 74.6%, respectively. Comparing 5-year graft patency according to the extent of arterial occlusion, patients with occlusion confined to the popliteal artery (n = 14) showed a better patency rate than patients with occlusion extended beyond the popliteal artery (n = 8) with no statistical significance (83.6% vs 53.6%; P = .053). Comparing 5-year graft patency according to the inflow artery, superficial femoral artery inflow (n = 6) showed a worse patency rate than popliteal artery inflow (n = 16) (30.0% vs 85.9%; P = .015). Conclusion: In advanced popliteal entrapment syndrome, longer bypass with superficial femoral artery inflow showed poor long-term graft patency rate. The graft patency rate was excellent in patients whose arterial occlusion was confined to the popliteal artery and treated by popliteal interposition graft with reversed saphenous vein. With these data, we suggest that longer bypass extending beyond the popliteal artery might only be indicated in patients with critical limb ischemia when the extent of disease does not allow short interposition graft. [ABSTRACT FROM AUTHOR]

Objective: Spontaneous isolated dissection of the superior mesenteric artery (SIDSMA) is extremely rare. Various treatment options are currently available, including conservative management, anticoagulation, endovascular stenting, and surgical repair. Herein, we present our experience in the treatment of symptomatic SIDSMA. Methods: A retrospective study was conducted on 14 consecutive patients with symptomatic SIDSMA between January 2000 and January 2010. All patients had acute onset abdominal pain. The decision to intervene was based on patient symptoms and signs, as well as the morphologic characteristics of superior mesenteric artery (SMA) dissection on computed tomography (CT) angiography. Endovascular stenting (ES) was indicated in patients with severe compression of the true lumen or dissecting aneurysm likely to rupture. Self-expandable stents were placed via a right common femoral approach. None of the patients underwent anticoagulation, and patients who underwent ES were maintained on antiplatelet therapy for 3 months postoperatively. Results: The median age of the study subjects was 59 years (range, 50-75 years). The median follow-up time was 27.5 months (range, 2-64 months). Treatment included conservative management without the use of anticoagulation in seven patients, ES in six, and necrotic bowel resection in one. Four patients with severe compression of the true lumen or large dissecting aneurysm underwent ES as a primary treatment. ES was additionally performed in two patients in whom initial conservative treatment failed (increasing dissecting aneurysm at 7-day follow-up CT scan in one and a reappearance of abdominal pain after resuming diet in the other). The median fasting time was significantly shorter in patients with primary ES (2.5 days) than in those managed conservatively (8.0 days). No complications associated with the SIDSMA or ES were developed. The patency of stents was demonstrated on follow-up CT scans up to 60 months (range, 1-60 months). Conclusions: Conservative management without anticoagulation can be applied successfully to the patients with symptomatic SIDSMA. Primary endovascular stenting is indicated if patients have suspected bowel ischemia, compression of the true lumen of the SMA >80%, or SMA aneurysm of >2.0 cm in diameter on initial CT scan. Endovascular stenting can also be provided to the patients in whom initial conservative treatment failed, as a rescue therapy. [Copyright &y& Elsevier]

Purpose: Computed tomography venography (CTV) with three-dimensional reconstruction can provide complementary road maps for varicose vein (VV) surgery. The purpose of this study is to verify the role of CTV in the treatment of VV in terms of advantages and complications. Methods: Ninety-four consecutive patients with VV underwent conventional high ligation, stripping, and varicosectomy by a single vascular surgeon in 2007. All patients were evaluated with duplex ultrasound and CTV. Patients with renal dysfunction, allergy to radiocontrast, telangiectasia only, or treated by endovenous laser therapy (EVLT) were excluded from the study. Computed tomography (CT) examination was performed with a 16-Multidetector CT scanner (Siemens, Erlangen, Germany) and 3D images were reconstructed by personal computer-based software (Rapidia, Infinitt, Seoul, Korea). Medical records and the CT images were reviewed retrospectively. Results: VV surgeries were done in 127 limbs of 94 patients (both in 33, right in 29, and left in 32). There were 56 females and 38 males with the mean age of 57 years (range, 28-79 years). The CEAP classification was C2-3 EpAsPr. Perforators larger than 1 mm near the varicose veins were detected and marked on the CT volume-rendering images. The average numbers of perforators marked by CTV were 12.07 ± 4.27 in each limb. The perforators were evaluated by duplex for the presence of reflux (≥0.5 sec). Mean number of perforators with reflux in each limb was 1.41 ± 1.67, which were ligated during the surgery. Incidental detections of other disease were done in six patients, including uterine myomas, an ovarian cyst, a gallstone, a scrotoal varicocele, and a pes anserine bursitis. Operation was performed with the CTV images on screen. CTV was helpful in designing the operation in most patients. Three-D CTV images of saphenopopliteal junction especially provided thorough understanding of the complex variable anatomy of the lesion. There were no CT-related complications, such as renal dysfunction or allergic reaction. Conclusions: CT venography can provide excellent road map for VV surgery without significant complications. It cannot replace duplex ultrasound, but can provide powerful 3D images for designing operation as well as education and research. [Copyright &y& Elsevier]

Purpose: Since the publication of Dialysis Outcomes Quality Initiative (DOQI) guidelines, the use of native veins for the construction of arteriovenous fistulas (AVF) for hemodialysis has been highly recommended rather than prosthetic arteriovenous grafts (AVG). Upper arm basilic vein transposition (BVT) has been accepted widely, with superior patency compared with AVG, but only a few studies have reported outcomes of forearm BVT (FBVT). This study evaluated the efficacy of FBVT compared with direct AVF (DAVF) and AVG in a tertiary referral center. Methods: From January 2005 to December 2007, 461 patients underwent AV access for hemodialysis in Seoul National University Hospital. We retrospectively reviewed the medical records and dialysis sheets and evaluated the current AVF function in the outpatient clinic or by telephone interviews. Patients were grouped by the operation type: DAVF, FBVT, and AVG. The outcomes compared were primary, assisted-primary and secondary patency rates, maturation failure, and complications. Result: The mean age was 59 years (range, 14-92 years), and 280 patients (60.7%) were male. By operation type, the 461 accesses were 389 DAVF (84.4%), 34 FBVT (7.4%), and 38 AVG (8.2%). Mean follow-up duration was 21 months (range, 1-51 months). The primary patency rates for DAVF, FBVT, and AVG were 67.6%, 41.5%, 35% at 12 months and 53.9%, 30.2%, 10.3% at 24 months, respectively. The secondary patency rates were 89.2%, 79.1%, 78.3% at 12 months and 83.8%, 74.4%, 64.9% at 24 months, respectively. Maturation failure occurred in five DAVF patients and in one FBVT patient. The infection rate was 0.3% in DAVF and 12.5% in AVG, but no infection occurred in patients with FBVT. Multivariate analysis revealed that age and history of previous access were associated with lower primary patency. Conclusion: Forearm BVT showed an acceptable, high 2-year patency rate and fewer thromboses and infectious complications than AVG. Forearm BVT could be considered before forming an upper arm AVF or forearm AVG, if the basilic vein is available. [Copyright &y& Elsevier]

Objective: Although the luminal changes of Takayasu arteritis are well depicted with conventional angiography, its mural changes can be best evaluated with spiral computed tomography (CT) angiography. Here, the authors investigated the patterns of aortic involvement in Takayasu arteritis by using CT angiography. Methods: CT angiography was performed from the carotid bifurcation to the iliac bifurcation in a consecutive 85 patients (M:F = 10:75, mean age: 37 years) with Takayasu arteritis. Two radiologists interpreted axial images and three-dimensional reconstructed images by consensus with respect to disease extent, lesion continuity, and disease activity based on mural and luminal changes on CT angiography. Results: Eighty-one (95%) patients had aortic involvement with or without aortic branch involvement, and the other four (5%) patients had only aortic branch involvement. In terms of aortic branches, the left common carotid artery (77%) and the left subclavian artery (76%) were most commonly involved. Extent of disease involvement assessed by mural change was wider than that assessed by luminal change in 52 (61%) patients. Although arterial involvement was contiguous in 69 (81%) patients, skipped lesions were identified in 16 (19%) patients. An analysis of mural findings revealed the coexistence of active and inactive lesions in nine (11%) patients. Conclusions: Aortic involvement in Takayasu arteritis can occur from the aortic root to below the iliac bifurcation, and isolated branch vessel involvement is also possible. In most patients, aortic involvement occurs in a contiguous, synchronous fashion. However, skipped involvement and the coexistence of active and inactive lesions also occur. [Copyright &y& Elsevier]

Purpose: To define the role of computed tomographic (CT) angiography in the evaluation of persistent sciatic artery and to identify its potential advantages as a diagnostic modality. Methods: Between July 2002 and August 2004, 307 consecutive patients underwent CT angiography for suspected lower-extremity arterial insufficiency. All CT angiograms were retrospectively reviewed to determine the presence and laterality of persistent sciatic artery and its associated vascular abnormalities, such as aneurysm, thrombus, distal thromboembolism, and atherosclerotic change. The relationship of persistent sciatic artery with adjacent structures, such as sciatic nerve, muscle, accompanying vein, and femoral artery, as well as the presence of other anomalies, was analyzed. Clinical data regarding the presenting symptoms and hospital course were obtained from patient charts. Results: Six persistent sciatic arteries, with or without occlusion, were identified in five female patients (age range, 54 to 80 years). CT angiography revealed unilateral persistent sciatic artery in four patients (left, 3; right, 1) and bilateral persistent sciatic artery in one patient. Aneurysm was present in two (mean size, 26 mm × 20 mm), thrombosis in three, and distal thromboembolism in all six persistent sciatic arteries. All persistent sciatic arteries coursed along the sciatic nerve and continued as popliteal artery. Characteristically, in all these instances, the superficial femoral arteries were hypoplastic and tapered smoothly. Anomalous popliteal venous drainage was noted in all ipsilateral limbs with persistent sciatic artery and even in contralateral limbs with normal superficial femoral artery in all but one. Conclusion: CT angiography enables the detection of persistent sciatic artery even in the presence of complete occlusion and is useful in the comprehensive evaluation of various complications and associated venous anomalies. It can potentially be used as the sole imaging modality for persistent sciatic artery. [Copyright &y& Elsevier]

Femoral-anterior tibial artery bypasses with autogenous grafts are difficult to perform when sufficiently long saphenous veins are not available. We performed 12 bypasses on patients with Buerger disease during a 20-year period using a new intermuscular tunneling technique. The graft is passed from the thigh between the muscle compartments without penetrating the muscle fibers, providing an anatomically superior and shorter path. The primary patency rates were 75% at 5 years and 65% at 10 years. We believe that our tunneling technique is safe and durable and might be a viable alternative for proximal femoral-anterior tibial artery bypass in selected patients. [ABSTRACT FROM AUTHOR]

We report a case of a 25-year-old Caucasian female with a septic thrombosis in the inferior vena cava (IVC) which contained a toothpick. She was admitted with fever and abdominal pain for 2 weeks. Computed tomography scan showed thrombus with air density in the suprarenal IVC. However, there was no evidence of duodenocaval fistula. Because of the patient''s reluctance for surgery, endovascular therapy was tried. A partially-deployed nitinol stent was used as a filter, and aspiration thrombectomy was performed. Unexpectedly, a toothpick was retrieved within the stent. Anticoagulants and antibiotics were administered. A follow-up computed tomography after 2 months showed total resolution of the residual thrombus. [ABSTRACT FROM AUTHOR]