Porous Lattice Structure of Femoral Stem for Total Hip Arthroplasty / Estructura de Diseño Poroso por Latice de Vástago Femoral para Artroplastia Total de Cadera

Abstract Total Hip Arthroplasty (THA) is one of the surgical procedures carried out satisfactorily in procedures for osteoarthritis and trauma lesions. ATC surgery reduces pain and improves the quality of life of young patients. Therefore, it is of great importance to improve the properties of hip implants, since current implants do not match their lifespan with the life expectancy of a young patient. This is because the solid prostheses that currently exist have a higher Young's modulus, and therefore are too rigid compared to the bone tissue. On the other hand, the cyclic and continuous loads to which the hip joint is subjected in daily activities, can cause loosening and consequent implant loss The present work proposes an implant manufactured with a porous lattice structure, which aims to reduce stiffness, allow bone growth and a more effective mechanical load transfer. Three computational models subjected to static charges were evaluated and compared: 1) healthy femur, 2) implanted femur with a commercial prosthesis, and 3) implanted femur with a prosthesis with lattice structure. For the computational analysis it was decided to perform a static analysis of a person standing on the left foot; a load equivalent to the body weight was applied on the head of the femur, balancing the reaction forces in the system of forces (contact force, body weight, and abductor muscle).. The results were shown in terms of displacement, compression and deformation. The model implanted with a prosthesis with a lattice design presented a slight decrease in displacement, and a decrease in compression and deformation values, which indicated that the proposed design has a better distribution and transport of the loads through its structure.

Resumen La artroplastia total de cadera (ATC) es uno de los tratamientos quirúrgicos llevados a cabo de manera satisfactoria en procedimientos para la osteoartritis y lesiones de trauma. La ATC reduce el dolor y mejora la calidad de vida de los pacientes. Por lo tanto, es de gran importancia mejorar las propiedades de los implantes de cadera, ya que los implantes actuales tienen un tiempo de vida útil y deben cumplir con las expectativas de rehabilitación para los pacientes. Esto se debe a que las prótesis sólidas que existen actualmente tienen un módulo de Young más elevado, y por lo tanto son demasiado rígidas a comparación del tejido óseo. Por otro lado, las cargas cíclicas y continuas a las que se ve sometida la articulación de la cadera en actividades diarias, pueden ser causa del aflojamiento y consecuente pérdida del implante. El presente trabajo propone un implante fabricado con una estructura porosa tipo látice, el cual tiene como objetivos reducir la rigidez, permitir crecimiento óseo y una transferencia de cargas mecánicas más efectiva. Se evaluaron y compararon tres modelos computacionales sometidos a cargas estáticas: 1) fémur sano, 2) fémur implantado con una prótesis comercial, y 3) fémur implantado con una prótesis con estructura látice. Para el modelo computacional se optó por hacer un análisis estático de una persona parada sobre el pie izquierdo; donde se aplicó una carga equivalente del peso corporal sobre la cabeza del fémur, equilibrando las fuerzas de reacción en el sistema de fuerzas (fuerza de contacto, peso corporal, y músculo abductor). Los resultados fueron mostrados en términos de desplazamiento, compresión y deformación. El modelo implantado con una prótesis con un diseño tipo látice presentó una ligera disminución de desplazamiento, y disminución en los valores de compresión y deformación, lo que indicó que el diseño propuesto posee una mejor distribución y transporte de las cargas a través de su estructura.

Extranodal and nodal diffuse large B cell lymphoma of the head and neck: two different entities?

This study analyzes patients with head and neck diffuse large B cell lymphoma (HN-DLBCL), focusing on the differences in the biological characteristics and prognosis of lymphomas of nodal and extranodal origin. We have included 72 patients with stage I-II HN-DLBCL who had updated survival information and diagnostic paraffin-embedded tissue blocks available for review. Non-germinal center phenotype (73.7 vs. 32.4 %, P = 0.001) and high level of Bcl-2 expression (78.9 vs. 52.9 %, P = 0.025) were more frequent in nodal than extranodal lymphomas. Univariate analyses indicated that bulky disease, Ann Arbor stage II, high level of Ki-67 expression, and primary nodal disease had adverse effects on complete remission (CR), but these effects were confirmed in a multivariate analysis for primary nodal disease and bulky disease. Patients with primary extranodal lymphoma also had better overall survival (OS) (87.7 vs. 72.5 %, P = 0.04) and event-free survival (EFS) (84 vs. 58.5 %, P = 0.046) than patients with nodal disease, although in the multivariate analysis, only Ann Arbor stage II continued to predict worse OS and EFS, whereas bulky disease was an independent prognostic factor only for EFS. We found significant differences in the biological characteristics and prognosis between primary nodal and extranodal HN-DLBCL.

The postprandial inflammatory response after ingestion of heated oils in obese persons is reduced by the presence of phenol compounds.

SCOPE: Heating during the process of cooking alters the chemical properties of foods and may affect subsequent postprandial inflammation. We tested the effects of four meals rich in different oils subjected to heating on the postprandial inflammatory metabolism of peripheral blood mononuclear cells (PBMCs). METHODS AND RESULTS: Twenty obese participants received four breakfasts following a randomized crossover design, consisting of milk and muffins made with different oils (virgin olive oil (VOO), sunflower oil (SFO), and a mixture of seeds oil (SFO/canola oil) with added either dimethylpolysiloxane (SOD), or natural antioxidants from olive mill wastewater alperujo (phenols; SOP)), previously subjected to 20 heating cycles. Postprandial inflammatory status in PBMCs was assessed by the activation of nuclear NF-κB, the concentration in cytoplasm of the NF-κB inhibitor (IκB-α), the mRNA levels of NF-κB subunits and activators (p65, IKKß, and IKKα) and other inflammatory molecules (TNF-α, IL-1ß, IL-6, MIF, and JNK), and lipopolysaccharide (LPS) levels. VOO and SOP breakfasts reduced NF-κB activation, increased IκB-α, and decreased LPS plasma concentration. SFO increased IKKα, IKKß, p65, IL-1b, IL-6, MIF, and JNK mRNA levels, and plasma LPS. CONCLUSION: Oils rich in phenols, whether natural (VOO) or artificially added (SOP), reduce postprandial inflammation, compared with seed oil (sunflower).

Cross-sensitivity between taxanes in patients with breast cancer.

AIM This study was a retrospective analysis of our experience with severe cross-hypersensitivity reactions (HSR) to the taxanes paclitaxel (P) and docetaxel (D) in patients with breast cancer. PATIENTS AND METHODS We evaluated patients with breast cancer treated with P or D who experienced severe HSR to one of the two taxanes. Severe HSR was defined as any reaction severe enough to warrant discontinuation of the drug. Initial intravenous premedication for paclitaxel was dexamethasone (20 mg), ranitidine (50 mg) and dexchlorpheniramine (10 mg). For docetaxel, dexamethasone (4 mg) orally every 12 hours was administered the day before infusion and dexamethasone (20 mg) was administered intravenously prior to infusion. After severe HSR to the taxane and 30 minutes before infusion of another taxane, we administered dexamethasone (20 mg), ranitidine (50 mg) and dexchlorpheniramine (10 mg) iv as a premedication, and we also increased the time of the infusion. RESULTS Between March 2009 and April 2010, 23 patients experienced an initial severe HSR to taxane (12 P, 11 D). Substitution of another taxane was conducted in 17 patients in the two weeks following the initial HSR. Eight patients had an initial HSR with P, and three had a cross-HSR to D. Nine patients had an initial HSR to D, and four of these patients had a cross-HSR to P. Among the 17 patients who received both taxanes, 7 (41%) had a cross-HSR. All cross- HSRs were sufficiently severe (grade 3-4) to suspend taxane treatment permanently. In the remaining 6 patients, a desensitisation protocol to taxanes was performed by increasing the dose of the diluted drug (4 P, 2 D), which resulted in administration of the drug without complications in all cases. There were no treatment-related deaths. CONCLUSION Severe cross-HSR between P and D occurred in a significant proportion of our patients with breast cancer, so care must be taken when substituting taxanes (paclitaxel and docetaxel). A desensitisation protocol can be an effective alternative to decrease the risk of a new HSR.

Androgen excess in women: experience with over 1000 consecutive patients.

The objective of the present study was to estimate the prevalence of the different pathological conditions causing clinically evident androgen excess and to document the degree of long-term success of suppressive and/or antiandrogen hormonal therapy in a large consecutive population of patients. All patients presenting for evaluation of symptoms potentially related to androgen excess between October 1987 and June 2002 were evaluated, and the data were maintained prospectively in a computerized database. For the assessment of therapeutic response, a retrospective review of the medical chart was performed, after the exclusion of those patients seeking fertility therapy only, or with inadequate follow-up or poor compliance. A total of 1281 consecutive patients were seen during the study period. Excluded from analysis were 408 patients in whom we were unable to evaluate hormonal status, determine ovulatory status, or find any evidence of androgen excess. In the remaining population of 873 patients, the unbiased prevalence of androgen-secreting neoplasms was 0.2%, 21-hydroxylase-deficient classic adrenal hyperplasia (CAH) was 0.6%, 21-hydroxylase-deficient nonclassic adrenal hyperplasia (NCAH) was 1.6%, hyperandrogenic insulin-resistant acanthosis nigricans (HAIRAN) syndrome was 3.1%, idiopathic hirsutism was 4.7%, and polycystic ovary syndrome (PCOS) was 82.0%. Fifty-nine (6.75%) patients had elevated androgen levels and hirsutism but normal ovulation. A total of 257 patients were included in the assessment of the response to hormonal therapy. The mean duration of follow-up was 33.5 months (range, 6-155). Hirsutism improved in 86%, menstrual dysfunction in 80%, acne in 81%, and hair loss in 33% of patients. The major side effects noted were irregular vaginal bleeding (16.1%), nausea (13.0%), and headaches (12.6%); only 36.6% of patients never complained of side effects. In this large study of consecutive patients presenting with clinically evident androgen excess, specific identifiable disorders (NCAH, CAH, HAIRAN syndrome, and androgen-secreting neoplasms) were observed in approximately 7% of subjects, whereas functional androgen excess, principally PCOS, was observed in the remainder. Hirsutism, menstrual dysfunction, or acne, but not alopecia, improved in the majority of patients treated with a combination suppressive therapy; although more than 60% experienced side effects.

Endoscopically assisted in situ lower extremity bypass graft: a preliminary report of a new minimally invasive technique.

OBJECTIVE: Lower extremity arterial reconstructions with in situ greater saphenous vein (GSV) are an important component of limb salvage surgery. Initially, the procedure was performed through continuous skin incisions for side branch occlusion and valve lysis with a wound complication rate of 5% to 25%. To decrease these complications, we used endoscopic GSV harvest equipment in 25 in situ vein bypass grafts in 25 patients performed over 24 months. METHODS: The procedures were performed with three skin incisions: two for arterial access and a 2-cm incision above the knee to insert the Endopath device (Ethicon) to locate and clip the GSV side branches. After completion of the proximal anastomosis, the valves were lysed through the distal end of the vein with a flexible valvulotome. Completion cineangiography was performed to confirm side branch occlusion and evaluate the entire reconstruction. The results of this technique were compared with our last 25 in situ bypass grafts done with standard long incisions. RESULTS: In the endoscopic group there was one (4%) minor wound complication (cellulitis). No postoperative arteriovenous fistulas were detected by means of duplex examination, and the average hospital stay was 6.2 +/- 1 days. One graft closed at 9 months as a result of distal vein hyperplasia, but the other grafts have remained patent, with follow-up from 6 to 30 months (mean, 18 months). Patients with the standard in situ bypass grafts had significantly (P < .05) more wound complications (20%) and longer average hospital stay (9.2 +/- 2 days) than the endoscopic group. Patency rates were comparable for both groups. CONCLUSION: These results show that less invasive endoscopic in situ bypass grafting minimizes wound complications and reduces the need for hospitalization without decreasing patency or increasing operative time.

Endoluminal graft repair for abdominal aortic aneurysms in high-risk patients and octogenarians: is it better than open repair?

OBJECTIVE: To analyze the short-term and midterm results of open and endoluminal repair of abdominal aortic aneurysms (AAA) in a large single-center series and specifically in octogenarians. METHODS: Between January 1997 and October 2000, 470 consecutive patients underwent elective repair of AAA. Conventional open repair (COR) was performed in 210 patients and endoluminal graft (ELG) repair in 260 patients. Ninety of the patients were 80 years of age or older; of these, 38 underwent COR and 52 ELG repair. RESULTS: Patient characteristics and risk factors were similar for both the entire series and the subgroup of patients 80 years or older. The overall complication rate was reduced by 70% or more in the ELG versus the COR groups. The postoperative death rate was similar for the COR and ELG groups in the entire series and lower (but not significantly) in the ELG 80 years or older subgroup versus the COR group. The 36-month rates of freedom from endoleaks, surgical conversion, and secondary intervention were 81%, 98.2%, and 88%, respectively. CONCLUSION: The short-term and midterm results of AAA repair by COR or ELG are similar. The death rate associated with this new technique is low and comparable, whereas the complication rate associated with COR in all patients and those 80 years or older in particular is greater and more serious than ELG repair. Long-term results will establish the role of ELG repair of AAA, especially in elderly and high-risk patients.

Evolution of vascular fellowship training in the new era of endovascular techniques.

PURPOSE: The endovascular technique has revolutionized the treatment of infrarenal abdominal aortic aneurysm (AAA). At our institution, we examined the impact of an endovascular program on the traditional operative training of the vascular fellows in the treatment of infrarenal AAA. METHODS: We examined the records of our vascular fellows' experience from July 1995 to May 2000. We introduced the endovascular treatment for infrarenal AAA in 1995. RESULTS: The fellows have performed increasing numbers of endovascular cases each year, with a predicted number of 124 cases for 1999-2000. However, despite an increase in the overall volume of patients with infrarenal AAA (102 cases in 1998-1999 and a predicted 160 cases in 1999-2000), the trainees will experience a reduction in the number of open AAAs from 61 cases in 1998-1999 to a predicted 36 cases in 1999-2000. However, the volume of open suprarenal AAA has also increased from eight cases in 1998 to 1999 to a predicted 24 cases in 1999-2000. With no significant change in the open aortoiliac occlusive cases from previous years, the current fellows will graduate with a similar volume of open aortic procedures as their predecessors. CONCLUSION: With the recent advances in endovascular technology, our traditional operative approach to the treatment of AAA disease may be lacking in the training of future vascular surgeons. At our institution, although fewer open infrarenal AAA cases were performed, the trainees have maintained the open aortic experience by performing an increased volume of suprarenal AAAs. We have to critically reevaluate and redefine what constitutes adequate vascular fellow experience in the surgical treatment of abdominal aortic aneurysms.

Applied pharmacoeconomics: modeling data from internal and external sources.

The use and application of techniques for modeling data obtained from various data sources are discussed. Modeling with internal and external data has become a popular way for health care organizations to apply pharmacoeconomics to pharmacy practice. Modeling studies use existing clinical and epidemiologic data to project the effect of a clinical, policy, or medication decision on a patient, population, or organization. Although several modeling techniques have been used in health care, the most common approaches are to modify and adapt existing models or to develop a unique model to answer questions of interest in a specific practice setting. Typically, an economic model developed by adapting an existing one will use either the clinical decision-analysis or Markov modeling technique. Regardless of the technique used, external data must be carefully evaluated to ensure that the data are appropriate for use in making decisions at a specific organization. For example, cost data must be analyzed to ensure that the calculations are reproducible. Also, it must be acknowledged that this strategy may not always be appropriate. The use of modeling techniques can assist decision-makers in making more informed clinical, policy, and medication decisions in real-world settings. Caution is required when adapting and interpreting existing models to ensure appropriate application in a specific organization.

Can a tissue-engineered skin graft improve healing of lower extremity foot wounds after revascularization?

A bilayered tissue-engineered skin graft composed of human neonatal foreskin fibroblasts and keratinocytes in a type I bovine collagen matrix has been developed. We sought to determine if this graft improves wound healing after lower extremity revascularization. Thirty-one previously ischemic foot wounds were randomly assigned to moist dressing changes or tissue-engineered skin graft within 60 days of revascularization. In the grafted group, 10 received meshed and 11 received unmeshed graft. Wound healing was followed by wound area measurements and photography. There were no statistically significant differences between groups in patient age, sex, diabetes or renal failure risk factors, revascularization procedure, or wound location or size. Treatment with tissue-engineered skin graft was significantly more effective than moist dressing in the percentage of wounds healed (62 vs. 0% at 8 weeks, 86 vs. 40% at 12 weeks, p < 0.01) and the median time to complete wound closure (7 vs. 15 weeks, p = 0.0021, rank-sum test). There was no difference in the wound closure rate of meshed and unmeshed graft at 4, 8, 12, or 24 weeks (p > 0.05). Three indolent localized wound infections in the tissue-engineered skin graft group were the only complication. Tissue-engineered skin grafting can be used safely in previously ischemic wounds after lower extremity revascularization. Treatment with this graft promotes healing more rapidly and in more patients than standard moist dressings. It obviates the risk, inconvenience, and expense of donor skin harvesting, anesthesia, and hospitalization associated with autologous skin grafting. This graft may represent an advance in the treatment of previously ischemic lower extremity foot wounds.

Stratified administration of serotonin 5-HT3 receptor antagonists (setrons) for chemotherapy-induced emesis. Economic implications.

The serotonin 5-HT3 receptor antagonists or 'setrons' have become the standard of care for the prevention of chemotherapy-induced emesis (CIE) and are first-line therapy for acute CIE in healthcare organisations worldwide. However, their superior efficacy versus standard antiemetics comes at a significant cost. Currently, 3 agents are available in the US: ondansetron, granisetron and dolasetron. The most important treatment-related factor contributing to CIE is the emetogenicity of chemotherapy. The ability to customise, or stratify, the setron dose to match the emetogenic challenge of the chemotherapy administered has potential benefits, both clinically and economically. In adults, there is an appreciable amount of clinical literature addressing stratified administration; however, the amount of 'hard' economic data is rather limited. Intuitively, if clinical outcomes are equivalent, then stratified administration should be associated with economic benefits, as it generally promotes the use of doses lower than those recommended by the manufacturer. The literature strongly substantiates this for ondansetron, but is not as favourable for granisetron or dolasetron. As the rationale and justification for dose stratification is contained in the clinical literature, the authors have reviewed the pertinent literature supporting the clinical and economic benefits of dose stratification in both adult and paediatric patients. The authors also provide a discussion of various additional strategies that can be employed to ensure the appropriate and cost-effective use of setrons in real-world practice settings. These strategies include the use of lower doses than recommended by manufacturers, use for acute versus delayed phase emesis, enhancing the antiemetic efficacy by the addition of a corticosteroid, use of oral versus injectable formulations (when appropriate) and the implementation and use of local, national and international drug use guidelines.

Repair of bilateral common iliac artery aneurysms coexisting with a pelvic horseshoe kidney.

This report describes the treatment of bilateral common iliac artery aneurysms in a patient with a pelvic horseshoe kidney. Anomalous renal arteries arising from the aorta, the common iliac arteries, and the left hypogastric artery were identified precisely by selective angiography. These multiple renal artery anomalies and the presence of a large pelvic horseshoe kidney complicated the surgical treatment of the aneurysms. The repair of the aneurysms was successfully accomplished by staged retroperitoneal procedures. This technique allowed excellent visualization of the iliac aneurysms and preservation of all renal arteries with intact renal function.

Midterm experience with the endovascular treatment of isolated iliac aneurysms.

PURPOSE: This report describes our 5-year experience with the endovascular repair of isolated iliac aneurysms and pseudoaneurysms. METHODS: Between June 1993 and July 1998, 40 isolated iliac aneurysms and pseudoaneurysms were treated with endovascular grafts in 39 patients. Thirty-seven aneurysms were treated with endovascular grafts composed of polytetrafluoroethylene grafts and balloon expandable stents, and the other three underwent repair with a polycarbonate urethane endoluminal graft. RESULTS: All the patients underwent initially successful endovascular treatment of isolated iliac aneurysms and pseudoaneurysms and were followed from 1 to 51 months (mean, 18 months). The 4-year primary patency rate was 94.5% +/- 10%. The perioperative complications included one episode of distal embolization, an episode of colonic ischemia, five episodes of kinking or compression of the endovascular graft, and one early postoperative graft thrombosis. There was only one perioperative death in a patient whose aneurysm ruptured in the operating room just before endovascular repair. The median postoperative length of hospital stay was 3.0 +/- 1.3 days in this group of patients at moderate and high risk. The long-term complications included one graft thrombosis and two endoleaks. One small endoleak was followed until the patient died of unrelated causes, and the other one led to aneurysm rupture in the only patient temporarily lost to follow-up examination. This patient successfully underwent treatment in the standard open surgical fashion. To date, all the other aneurysms have remained stable or have decreased in size during the follow-up examinations with duplex or contrast-enhanced computed tomographic scans. CONCLUSION: Endovascular repair of iliac aneurysms and pseudoaneurysms is a safe and effective technique with good midterm results in patients at standard and high risk. These grafts are particularly beneficial for patients with medical, surgical, or anatomic contraindications for open surgical repair.

When is urokinase treatment an effective sole or adjunctive treatment for acute limb ischemia secondary to native artery occlusion?

BACKGROUND: Intra-arterial thrombolytic therapy is currently a therapeutic option for the treatment of acute limb ischemia. A recent large prospective randomized trial (TOPAS) comparing lytic therapy and operative intervention showed that both forms of treatment had similar results in terms of amputation-free survival. However, the exact role for lytic treatment is unclear. METHOD: Over a 4-year period we treated 60 cases of acute limb ischemia in 57 patients secondary to native artery occlusion with thrombolytic therapy with urokinase. All patients were evaluated at 1 week, 1 month, and then at 3-month intervals posttreatment. Follow-up evaluations included pulse examination, pulse volume recordings, and duplex examinations to confirm arterial patency. No patients were lost to follow-up with a range of 8 to 54 months (mean 26). RESULTS: Of these 60 native arterial occlusions, complete lysis was achieved in 46 cases (76%). Of these 46 cases, 18 required lysis only, 19 cases (9 iliac, 7 superficial femoral artery (SFA), and 3 popliteal) required angioplasty of lesions uncovered by clot lysis, and 9 patients had lysis and angioplasty of iliac arteries followed by infrainguinal bypasses. Eight of the 57 patients (14%) who had been asymptomatic presented with symptoms limited to new onset claudication, all of which were successfully lysed. Cumulative patency for the 43 successful cases was 90% +/- 5% at 1 year and 75% +/- 4% at 2 years. The 1-year amputation-free survival for all native artery occlusions was 85% +/- 6%. CONCLUSION: Thrombolysis with urokinase simplified the treatment of native arterial occlusion proving to be the sole therapy in 18 (29%) patients or a valuable adjunct by facilitating the angioplasty of arterial lesions and avoiding open surgery in 60% of patients treated. In addition, the correction of inflow lesions reduced the magnitude of required subsequent bypass procedures to achieve limb salvage. In conclusion, successful thrombolysis of native artery occlusion provided durable arterial patency and limb salvage, particularly in patients with new onset claudication.

Analysis of endovascular graft treatment for aortoiliac occlusive disease: what is its role based on midterm results?

OBJECTIVE: To analyze the authors' midterm results (up to 4 years) using endovascular grafts to treat aortoiliac occlusive disease in patients with limb-threatening ischemia. SUMMARY BACKGROUND DATA: Endovascular grafts are being used to manage some aortoiliac lesions formerly treated by aortofemoral or extraanatomic bypass grafts. However, widespread acceptance of these new grafts depends on their late patency and clinical utility. METHODS: Between January 1993 and December 1997, 52 patients with aortoiliac occlusive disease were treated with endovascular grafts. The primary indication for treatment was gangrene or ulceration in 42 patients (81%) and rest pain in 10 patients (19%). Sixteen patients had symptomatic contralateral limbs that were also treated, and 27 (52%) patients required a synchronous infrainguinal bypass. Results up to 4 years were evaluated by life table analysis. RESULTS: Forty-six (88%) of the patients had complete follow-up of 3 to 57 months (median 22 months). Six patients were lost to follow-up at a mean of 20 months after surgery. The 4-year primary and secondary patency rates for the endovascular grafts were 66.1% and 72.3% respectively. Six patients required a major amputation, and the limb salvage rate was 88.7%. Four-year patient survival was 37%, with 23 patients dying during this follow-up period. CONCLUSIONS: Endovascular grafts can often be used when conventional procedures are contraindicated or technically impractical. These grafts are a valuable alternative to extraanatomic and aortofemoral bypasses in high-risk patients with aortoiliac occlusive disease and critical ischemia.

Early experience with the Corvita endoluminal graft for treatment of arterial injuries.

The aim of this study was to evaluate our early experience with the Corvita endoluminal graft for the treatment of a variety of arterial injuries. Ten patients with arterial pseudoaneurysms (8) or arteriovenous fistulas (2) due to arterial injuries were followed prospectively after undergoing treatment with the endovascular graft. Our results showed that the Corvita low-profile endoluminal graft can be successfully used to treat arterial injuries but that it sometimes requires the placement of additional stents in patients with tortuous or tapering vessels. These grafts are extremely useful for the safe treatment of difficult and high-risk patients. Further improvements in available endovascular grafts and good long-term results will be necessary before considering these grafts the best treatment available for most patients with significant arterial injuries.

Can duplex scan arterial mapping replace contrast arteriography as the test of choice before infrainguinal revascularization?

PURPOSE: Arteriography is the diagnostic test of choice before lower extremity revascularization, because it is a means of pinpointing stenotic or occluded arteries and defining optimal sites for the origin and termination of bypass grafts. We evaluated whether a duplex ultrasound scan, used as an alternative to arteriography, could be used as a means of accurately predicting the proximal and distal anastomotic sites in patients requiring peripheral bypass grafts and, therefore, replace standard preoperative arteriography. METHODS: Forty-one patients who required infrainguinal bypass grafts underwent preoperative duplex arterial mapping (DAM). Based on these studies, an observer blinded to the operation performed predicted what operation the patient required and the best site for the proximal and distal anastomoses. These predictions were compared with the actual anastomotic sites chosen by the surgeon. RESULTS: Whether a femoropopliteal or an infrapopliteal bypass graft was required was predicted correctly by means of DAM in 37 patients (90%). In addition, both anastomotic sites in 18 of 20 patients (90%) who had femoropopliteal bypass grafts and 5 of 21 patients (24%) who had infrapopliteal procedures were correctly predicted by means of DAM. CONCLUSION: DAM is a reliable means of predicting whether patients will require femoropopliteal or infrapopliteal bypass grafts, and, when a patient requires a femoropopliteal bypass graft, the actual location of both anastomoses can also be accurately predicted. Therefore, DAM appears able to replace conventional preoperative arteriography in most patients found to require femoropopliteal reconstruction. Patients who are predicted by means of DAM to require crural or pedal bypass grafts should still undergo preoperative contrast studies to confirm these results and to more precisely locate the anastomotic sites.

Percutaneous transluminal angioplasty for the treatment of limb threatening ischemia: do the results justify an attempt before bypass grafting?

PURPOSE: Results of percutaneous transluminal angioplasty (PTA) in selected cases have been reported to be equal or superior to those of arterial bypass graft surgery, with a lower morbidity and mortality. We performed PTA of stenotic or occlusive lesions in patients with limb-threatening ischemia, hoping to improve our overall success and decrease morbidity in this group of patients. The results of PTA in the limb-salvage setting was evaluated. METHODS: From 1992 to 1995, 307 PTAs were performed in 257 patients. One hundred sixty-one (63%) patients had diabetes mellitus, and 32 (12%) patients had renal failure. All patients were evaluated by means of pulse volume recordings and ankle brachial indices at 1 and 6 weeks after PTA and at 3 month intervals thereafter. Seventeen patients (9%) were lost to follow-up. The continued success or failure of PTA was defined by means of noninvasive vascular laboratory criteria, patency by means of pulse examination, the need for subsequent bypass grafting across the index lesion, and limb salvage. RESULTS: The 1-year patency rates for external iliac PTAs (56%) were significantly lower (P <.05) than those for common iliac PTAs (87%). Infrainguinal PTAs at the femoral, popliteal, and tibial level had 1-year patency rates of less than 15%. CONCLUSION: Common iliac artery PTA is justified in most cases in which it is feasible. However, when PTAs are performed below the inguinal ligament, the results are markedly worse. One-year patency rates of PTA in this group of patients with threatened limbs are inferior to the patency rates of arterial bypass grafts, even when these bypasses are performed with a prosthetic material. PTA should not be considered as a primary treatment modality for patients with infrainguinal arterial occlusive disease who also have limb-threatening ischemia, except in unusual circumstances.

Endovascular treatment of a ruptured lumbar artery aneurysm: case report and review of the literature.

Lumbar artery aneurysms are uncommon lesions that usually present as pseudoaneurysms secondary to vessel injury. Despite their small size and retroperitoneal location, these lesions are potentially lethal once they rupture. This report describes a ruptured lumbar artery aneurysm which was successfully treated in a minimally invasive fashion. The diagnosis was suggested by computed tomography scan and confirmed with angiography. Successful treatment consisted of placing intravascular metallic coils into the lumbar artery. The literature contains only seven previous reports of ruptured lumbar artery aneurysms and these were managed either operatively or via an endovascular approach. Based upon the outcome of all reported cases, we believe that coil embolization of lumbar artery aneurysms following diagnostic angiography is an appropriate and effective mean of treating these lesions.