The Protégé Nitinol Self-Expanding Stent for the Treatment of Iliofemoral Veno-Occlusive Disease.

PURPOSE: To evaluate the safety and effectiveness of the Protégé nitinol self-expanding stent for the treatment of iliofemoral veno-occlusive disease. MATERIALS AND METHODS: A retrospective review was performed of 376 (284 left, 92 right) Protégé stents in 212 limbs of 183 patients (mean age: 53 ± 17 years, 52% female) treated for iliofemoral veno-occlusive disease between 2011 and 2018. Binary patency was assessed with duplex ultrasound and calculated by Kaplan Meier analysis. Clinical outcomes were evaluated by clinical-etiology-anatomy-pathophysiology (CEAP) classification and Villalta scores. Adverse events were recorded and categorized per Society of Interventional Radiology reporting standards. RESULTS: Of the 212 limbs, 125 presented with acute thrombosis and 28 with chronic thrombosis requiring thrombectomy (n = 44), catheter directed thrombolysis (n = 32), or both (n = 77). Fifty-nine limbs were non-thrombotic. Mean follow-up time was 11.44 ± 11.37 months. Kaplan Meier analysis revealed a primary limb-level patency of 92.3%, 88.6%, 86.9% and 86.9% at 6, 12, 24 and 36 months, respectively. CEAP and Villalta scores improved from a median of C3 (range: 0-6) to C1 (0-5) (p < 0.001) and from a mean of 13.4 ± 7.5 to 5.3 ± 4.9 (p < 0.001), respectively. Nine minor and 2 major adverse events were recorded. CONCLUSIONS: Endovascular treatment of iliofemoral veno-occlusive disease with the Protégé self-expanding stent appears to have good mid-term patency. LEVEL OF EVIDENCE: Level 4, Case Series.

Safety of Therapeutic Anticoagulation with Low-Molecular-Weight Heparin or Unfractionated Heparin Infusion during Catheter-Directed Thrombolysis for Acute Pulmonary Embolism.

PURPOSE: To examine the safety of therapeutic-dose anticoagulation during catheter-directed thrombolysis (CDT) for acute pulmonary embolism (PE). MATERIALS AND METHODS: A retrospective review of 156 consecutive cases (age, 56.6 ± 15.4 years; 85 males) of CDT with alteplase for acute PE (symptoms, <14 days) between 2009 and 2019 was performed. All patients received full-dose anticoagulation before, during, and after thrombolysis with low-molecular-weight heparin (LMWH) (n = 45) or unfractionated heparin (n = 111) infusion. Massive PE was diagnosed in 21 of 156 patients at presentation; submassive PE was diagnosed in 135 of 156 patients at presentation. The Simplified Pulmonary Embolism Severity Index was ≥1 in 69 of 156 patients. RESULTS: There were 4 mild (2.6%), 3 moderate (1.9%), and 3 severe (1.9%) hemorrhagic complications (Global Use of Strategies to Open Occluded Arteries), 1 of which (0.6%) was intracranial. No significant differences in hemorrhagic complication rates (P = .3, P = 1.0, and P = .6, respectively) or general complication rates (Society of Interventional Radiology [SIR] minor, P = .2; SIR major, P = .7) were noted between the LMWH and heparin groups. Mean pulmonary arterial pressure for the entire cohort improved from 28.9 ± 7.6 mmHg to 20.4 ± 6.5 mmHg (P < .001), whereas the Miller score improved from 19.3 ± 4.6 to 7.3 ± 3.9 (P < .001). The average infusion duration was 26 ± 11.9 hours over 2.3 ± 0.6 total visits to the angiography lab, during which a mean of 27.85 ± 14.2 mg of tissue plasminogen activator were infused. CONCLUSIONS: Therapeutic anticoagulation during CDT for PE appears to be safe. The current study did not find a significant difference between LMWH and heparin infusion with respect to hemorrhagic and general complication rates.

Comparison of Ultrasound-Accelerated versus Pigtail Catheter-Directed Thrombolysis for the Treatment of Acute Massive and Submassive Pulmonary Embolism.

PURPOSE: To compare the technical and clinical effectiveness of ultrasound-accelerated endovascular thrombolysis (USAT) versus pigtail catheter-directed thrombolysis (PCDT) for the treatment of acute pulmonary embolism (PE). MATERIALS AND METHODS: A single-center retrospective study of patients treated with USAT or PCDT for acute massive or submassive PE between January 2010 and December 2016 was performed by reviewing electronic medical records. Sixty treatments were reviewed (mean patient age, 56.7 y ± 14.6), including 52 cases of submassive PE (21 treated with USAT, 31 with PCDT) and 8 cases of massive PE (3 treated with USAT, 5 with PCDT). Endpoints included pulmonary artery pressure (PAP), Miller PE severity index, tissue plasminogen activator (TPA) dose, infusion duration, procedural variables, and complications. RESULTS: Demographics, PE severity, and right:left ventricular diameter ratios were similar between groups. USAT and PCDT significantly reduced mean PAP (reductions of 7.4 mm Hg [P = .002] and 8.2 mm Hg [P < .001], respectively) and Miller index scores (reductions of 45.8% [P < .001] and 53% [P < .001], respectively) with similar effectiveness (P = .47 and P = .15, respectively). Procedure (P < .001) and fluoroscopy (P = .001) times were significantly longer in the USAT group. The USAT group underwent fewer sessions (2.2 ± 0.6 vs 2.4 ± 0.6; P = .17) with shorter infusion times (23.9 h ± 8.8 vs 30.4 h ± 12.6; P = .065) and a lower total dose of TPA (27.1 mg ± 11.3 vs 30.4 mg ± 12.6; P = .075) compared with the PCDT group, but the differences were not significant. Complications (P = .07) and 30-day mortality rates (P = .56) were not significantly different between groups. CONCLUSIONS: USAT and PCDT demonstrated comparable effectiveness and safety in the treatment of patients with acute PE.

Recanalization of chronic total occlusions of the superior mesenteric artery in patients with chronic mesenteric ischemia: technical and clinical outcomes.

PURPOSE: To evaluate the safety and outcomes of endovascular recanalization of chronic total occlusions (CTOs) of the superior mesenteric artery (SMA) in patients with chronic mesenteric ischemia (CMI). MATERIALS AND METHODS: A single-institution retrospective review was performed of 47 consecutive patients (18 male, 29 female) who underwent endovascular stent placement for CTOs of the SMA between February 2006 and November 2012. All patients had symptoms of CMI. Procedural and follow-up data were collected for assessment of technical success, safety, and outcome. RESULTS: Technical success was achieved in 41 of 47 patients (87%). Forty-two of the 47 procedures were performed from a femoral approach. Fifteen patients underwent concurrent revascularization of the celiac artery. All patients who underwent successful recanalization reported symptomatic improvement. Kaplan-Meier analysis revealed primary freedom from symptomatic recurrence of 95% at 12 months and 78% at 24 months. Symptomatic recurrence was observed in seven patients, all of whom underwent successful assisted or secondary endovascular procedures. Secondary freedom from symptomatic recurrence rates were 100% at 12 months and 88% 24 months. There were three (7%) minor access-related complications and no major complications. CONCLUSIONS: Endovascular stent-assisted recanalization of chronic SMA occlusions is safe and effective, with an acceptable rate of technical success and excellent midterm clinical outcomes.

Endovascular recanalization of native chronic total occlusions in patients with failed lower-extremity bypass grafts.

PURPOSE: To investigate the feasibility, safety, and outcome of endovascular recanalization of native chronic total occlusions (CTOs) in patients with failed lower-extremity bypass grafts. MATERIALS AND METHODS: Retrospective review of 19 limbs in 18 patients with failed lower-extremity bypass grafts that underwent recanalization of native arterial occlusions between February 2009 and April 2013 was performed. Nine of the limbs presented with acute ischemia and 10 presented with chronic ischemia, including eight with critical limb ischemia and two with disabling claudication. RESULTS: The mean patency of the failed bypass grafts (63% venous) was 27 months. All limbs had Transatlantic Inter-Society Consensus class D lesions involving the native circulation. Technical success of the endovascular recanalization procedure was achieved in all but one limb (95%). The mean ankle brachial indices before and after treatment were 0.34 and 0.73, respectively. There were no major complications or emergency amputations. Mean patient follow-up was 64 weeks, and two patients were lost to follow-up. Primary patency rates at 3, 6, and 12 months were 87%, 48%, and 16%, respectively. Successful secondary procedures were performed in seven patients, with secondary patency rates at 3, 6, and 12 months of 88%, 73%, and 44%, respectively. Limb salvage rates at 12 and 24 months were 94% and 65%, and amputation-free survival rates at 12 and 24 months were 87% and 60%, respectively. CONCLUSIONS: Endovascular recanalization of native CTOs in patients with failed lower-extremity bypass grafts is technically feasible and safe and results in acceptable limb salvage.

Spontaneous perirenal hemorrhage: what radiologists need to know.

Spontaneous perirenal hemorrhage (SPH), also known as Wünderlich's syndrome, is a rare urological emergency. This article reviews the most common causes of SPH and the role of imaging in establishing the correct diagnosis and in guiding the appropriate therapy. A thorough understanding of underlying etiologies, imaging appearances, optimal imaging techniques, and follow-up protocols are crucial to recognize patients with SPH due to benign disease and avoid unnecessary nephrectomies.

Bowel preparation for CT colonography: blinded comparison of magnesium citrate and sodium phosphate for catharsis.

PURPOSE: To compare colonic cleansing and fluid retention of double-dose magnesium citrate with those of single-dose sodium phosphate in patients undergoing computed tomographic (CT) colonography. MATERIALS AND METHODS: This retrospective HIPAA-compliant clinical study had institutional review board approval; informed consent was waived. The study included 118 consecutive patients given single-dose sodium phosphate for bowel catharsis and 115 consecutive patients at risk for phosphate nephropathy, who were instead given double-dose magnesium citrate. The bowel preparation regimen was otherwise identical. Four-point scales were used to assess residual stool and fluid in the six colonic segments, and attenuation of residual fluid was measured. An a priori power analysis was performed, and unpaired t tests with Welch correction were used to compare the two groups on stool and fluid scores and fluid attenuation. RESULTS: Both cathartic regimens offered excellent colon cleansing, with no significant difference for residual stool in any of the six segments. Stool scores of 1 or 2 (ie, no residual stool or residual stool <5 mm) were recorded in 88.6% (627 of 708) of colonic segments in the sodium phosphate group and in 88.1% (608 of 690) in the magnesium citrate group. No clinically important differences were seen in residual fluid scores in any of the six segments, with the only significant difference seen in the sigmoid colon (2.17 for sodium phosphate vs 2.44 for magnesium citrate; P< 0.01). Fluid attenuation was significantly different between magnesium citrate and sodium phosphate groups (790 HU +/- 216 vs 978 HU +/- 160; P <.001). CONCLUSION: Both sodium phosphate and magnesium citrate provided excellent colon cleansing for CT colonography. Residual stool and fluid were similar in both groups, and fluid attenuation values were closer to optimal in the magnesium citrate group. Since bowel preparation provided by both cathartics was comparable, magnesium citrate should be considered for CT colonography, particularly in patients at risk for phosphate nephropathy.

Utility of SPECT/CT as an adjunct to planar whole body I-131 imaging: liver metastasis from papillary thyroid cancer.

One of the major limitations of planar I-131 imaging is its lack of anatomic precision. SPECT/CT offers the benefit of precise anatomic localization that planar imaging lacks. Whether for confirmation of physiologic uptake or true pathology, SPECT/CT has an important role to play in clarifying equivocal findings. We present a case of papillary thyroid cancer metastatic to the liver, a relatively rare scenario. SPECT/CT allowed definitive lesion characterization at the time of the patient's visit to the nuclear medicine department.

Pitfalls of I-131 whole body scan interpretation: bronchogenic cyst and mucinous cystadenoma.

Whole body iodine scans are routinely performed in the nuclear medicine department as part of the management of differentiated thyroid carcinoma. Similarly, radioactive iodine has a well-established role as an adjunct to thyroidectomy in the treatment of these patients. A thorough understanding of the normal, benign, and pathologic biodistribution of iodine is imperative for the nuclear medicine physician. This knowledge leads to the accurate determination of the presence of metastatic or recurrent carcinoma, and may even facilitate the accurate detection of an undiagnosed condition. Above all, correct image interpretation avoids unnecessary therapeutic doses. The authors describe 2 unusual examples of false positive findings in fluid-filled cavities that showcase the variety of nonmalignant entities one may encounter when interpreting metastatic surveys.