Dynamic quantitative nonenhanced magnetic resonance angiography of the abdominal aorta and lower extremities using cine fast interrupted steady-state in combination with arterial spin labeling: a feasibility study.

BACKGROUND: Cine fast interrupted steady-state in combination with arterial spin labeling is a recently described nonenhanced magnetic resonance angiography (MRA) technique that relies on bolus tracking for time-resolved digital subtraction angiography-like displays of blood flow patterns. We evaluated the feasibility of applying this technique to display in-plane flow patterns in two regions: the abdominal aorta and lower extremity peripheral arteries. METHODS: We performed an institutional review board-approved study in healthy subjects and patients. In 7 healthy subjects, in-plane flow was imaged at 4 stations ranging from the lower legs to the aorto-iliac bifurcation (junction of the distal thigh and upper calf, mid-thigh, junction of the upper thigh and pelvis, upper pelvis). In 5 healthy subjects and 6 patients without abdominal aortopathy, images were acquired through the suprarenal abdominal aorta. Ten patients with known peripheral arterial disease and two patients with stable disease of the abdominal aorta were also evaluated. Peak velocity was compared at each of the 4 stations for cine fast interrupted steady-state in combination with arterial spin labeling and two-dimensional cine phase contrast in patients with normal vessels. RESULTS: In-plane flow patterns were well visualized in all peripheral arterial stations and in the abdominal aorta, providing a high quality display of hemodynamic patterns along extensive lengths of the vessels. There was very strong positive correlation (r = 0.952, P < 0.05) and excellent agreement (intraclass correlation coefficient, 0.935; 95% confidence interval, 0.812-0.972) between peak flow velocities measured by cine fast interrupted steady-state in combination with arterial spin labeling and two-dimensional cine phase contrast. In 10 patients with peripheral artery disease and 2 patients with aortic pathology, cine fast interrupted steady-state in combination with arterial spin labeling provided a visual demonstration of abnormal hemodynamics. CONCLUSION: This feasibility study suggests that cine fast interrupted steady-state in combination with arterial spin labeling provides an efficient, high quality and physiologically accurate display of in-plane flow patterns over extensive lengths of the lower extremity peripheral arteries, which can be difficult to achieve using other MRA techniques.

Embolization of Onyx Causing Acute Limb Ischemia.

We present the case of a patient with a refractory type II endoleak treated with translumbar Onyx with passage of the Onyx material into the endograft and subsequent embolization to the infrainguinal vasculature. This report represents a new complication of Onyx embolization that, to our knowledge, has not previously been described in the literature.

Primary aortoduodenal fistula supplied by type II endoleak.

Aortoenteric fistulas are a rare but potentially lethal condition. Here we present an unusual case of a fistula between the excluded portion of an infrarenal aneurysm repaired by stent-grafting and the duodenum. The fistula was supplied by a type II endoleak. The patient was successfully treated by extra-anatomic bypass grafting and removal of the aneurysm sac and the stent-graft.

Predictors of active cancer thromboembolic outcomes: mortality associated with calf deep vein thrombosis.

BACKGROUND: Venous thromboembolism (VTE) is a leading cause of mortality in patients with cancer. Outcomes, including mortality data, in the cancer population are limited in those with calf deep vein thrombosis (CDVT) compared to individuals with proximal deep vein thrombosis. The aim of this study was to assess the prognosis among patients with active cancer and CDVT. METHODS: Single institution inception cohort of cancer-associated CDVT patients who presented with thrombosis distal to popliteal level confirmed objectively by ultrasound. We defined active cancer as metastatic disease or use of chemotherapy at diagnosis. Clinical and laboratory data were extracted from the electronic health records. The Khorana Risk Score (KRS) was extracted based on data at entry. Institutional review board approval was obtained prior to the analysis. Categorical variables are expressed as percentages and continuous variables as median (interquartile range). Kaplan-Meier method, Pearson's χ2, Mann-Whitney U and Cox proportional hazard were applied. SPSS software version 22 was used for all statistics. RESULTS: One hundred nine patients (men=44 [40%], Age>65=89 [82%], BMI>30=25 [23%], Smoker=59 [54%]) were included. The majority had a low (30%) or intermediate KRS (64%) at diagnosis. Forty-seven percent died during a median follow-up time of 2.5 years (0.5-3.1). After multivariate analysis, the predictors of mortality were: smoking (hazard ratio [HR] 2.3; 95% CI: 1.2-4.7), metastasis (HR=5.8; 95% CI: 2.9-11.7), gastrointestinal cancer (HR=3.9; 95% CI: 1.8-8.5), and lung cancer (HR=4.1 95% CI: 1.7-10.3). VTE specific variables not associated with mortality included: bilateral CDVT, concomitant pulmonary embolism, multiple vein involvement, filter placement, or a surgery-associated event. The KRS was not predictive of death. CONCLUSIONS: Cancer-specific variables and smoking predicted mortality among CDVT patients in this cohort, rather than VTE characteristics at the time of CDVT diagnosis.

Günther-Tulip inferior vena cava filter removal 3334 days after placement.

The Günther-Tulip inferior vena cava filter (Cook Medical Inc, Bloomington, Ind) was one of the first inferior vena cava (IVC) filters to be approved by the U.S. Food and Drug Administration for retrieval. Clinical experience has documented that these IVC filters may be safely removed after 12 weeks of implantation. Recent reports have shown that the longer the indwelling time, the higher the retrieval failure rate. We present a case of a successful retrieval of a Günther-Tulip IVC filter 3334 days after implantation. Removal of the Günther-Tulip IVC filter is technically feasible, even after a prolonged indwelling time.

Complications of indwelling retrievable versus permanent inferior vena cava filters.

OBJECTIVE: Retrievable inferior vena cava (IVC) filters are appealing because they are designed for either retrieval or long-term use. However, the long-term safety of indwelling retrievable compared with permanent filters is largely unknown. This study was undertaken to compare complication rates and types associated with indwelling retrievable and permanent filters. METHODS: A retrospective review identified 1234 IVC filters (449 retrievable, 785 permanent) placed in 1225 patients from 2005 to 2010. Patients with retrievable filters removed electively were excluded, yielding 383 patients in whom retrievable filters were left in place. These patients with indwelling retrievable filters were compared with those with permanent filters with respect to demographics, comorbidities, survival, and complication rate and type. Differences in patient characteristics were tested with χ(2), Fisher exact, and Wilcox rank-sum tests. Logistic regression was used to identify predictors of complications. Because there were differences in the characteristics of the patients with indwelling retrievable filters and permanent filters, an additional propensity score analysis was performed yielding 319 patients in each group. RESULTS: Patients with indwelling retrievable filters were younger than those with permanent filters (mean age, 62 vs 75 years; P < .0001). Patients with indwelling retrievable filters had significantly more complications than those with permanent filters (9% vs 3.0%; P < .0001) after mean follow-up of 20 months (range, 0-86 months). Filter complications were categorized as thrombotic, device related, or systemic. While the most common complication type with both indwelling retrievable and permanent filters was thrombotic (4.4% vs 2.2%; P = NS), device-related complications were significantly more common with indwelling retrievable filters compared with permanent filters (3% vs 0.5%; P < .006). Propensity score analysis demonstrated that even in the matched groups, indwelling retrievable filters were associated with significantly more complications than permanent filters (9.1% vs 3.5%; P = .0035). CONCLUSIONS: Indwelling retrievable IVC filters were associated with significantly higher complication rates than permanent filters. Both thrombotic and device-related complications were more common with retrievable filters. Long-term use of retrievable filters should be avoided, especially considering the younger population in whom they are placed.

Triceps denervation as a predictor of elbow flexion contractures in C5 and C6 tetraplegia.

OBJECTIVE: To determine whether the existence of elbow flexion contractures in persons with C5 or C6 tetraplegia is related to a lack of residual voluntary triceps function and triceps denervation (ie, lower motoneuron damage). DESIGN: A retrospective study of impairment data from 74 arms to identify the incidence of elbow flexion contractures and the contributing factors toward this deformity. SETTING: Five spinal cord injury (SCI) rehabilitation centers in the United States, 1 in England, and 1 in Australia. PARTICIPANTS: Forty-three subjects with motor complete C5 or C6 traumatic SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Active and passive elbow extension, triceps voluntary muscle strength, and triceps response to electric stimulation. RESULTS: Subjects with weak voluntary triceps had significantly fewer and less severe elbow flexion contractures than those with paralyzed triceps ( P =.024). Subjects with completely denervated triceps (ie, no response to electric stimulation) had significantly more elbow flexion contractures than subjects with even a weak response to electric stimulation ( P =.003). Overall, 51% of the arms could not be passively extended to zero. Forty-six percent of the arms classified as C5 lacked full passive elbow extension, compared with 63% of the arms classified as C6 ( P =.302). CONCLUSIONS: A relationship has been found between elbow flexion contractures and lack of residual voluntary triceps and triceps denervation in subjects with C5 or C6 tetraplegia. There should be a greater awareness of the elbow flexion contractures that may develop as a result of this relationship. A better understanding of this deformity and its characteristics can lead to more effective clinical treatment and prevention strategies.