Dosimetric measurements of Onyx embolization material for stereotactic radiosurgery

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135017/1/mp7918.pd

Can we explain machine learning-based prediction for rupture status assessments of intracranial aneurysms?

Although applying machine learning (ML) algorithms to rupture status assessment of intracranial aneurysms (IA) has yielded promising results, the opaqueness of some ML methods has limited their clinical translation. We presented the first explainability comparison of six commonly used ML algorithms: multivariate logistic regression (LR), support vector machine (SVM), random forest (RF), extreme gradient boosting (XGBoost), multi-layer perceptron neural network (MLPNN), and Bayesian additive regression trees (BART). A total of 112 IAs with known rupture status were selected for this study. The ML-based classification used two anatomical features, nine hemodynamic parameters, and thirteen morphologic variables. We utilized permutation feature importance, local interpretable model-agnostic explanations (LIME), and SHapley Additive exPlanations (SHAP) algorithms to explain and analyze 6 Ml algorithms. All models performed comparably: LR area under the curve (AUC) was 0.71; SVM AUC was 0.76; RF AUC was 0.73; XGBoost AUC was 0.78; MLPNN AUC was 0.73; BART AUC was 0.73. Our interpretability analysis demonstrated consistent results across all the methods; i.e., the utility of the top 12 features was broadly consistent. Furthermore, contributions of 9 important features (aneurysm area, aneurysm location, aneurysm type, wall shear stress maximum during systole, ostium area, the size ratio between aneurysm width, (parent) vessel diameter, one standard deviation among time-averaged low shear area, and one standard deviation of temporally averaged low shear area less than 0.4 Pa) were nearly the same. This research suggested that ML classifiers can provide explainable predictions consistent with general domain knowledge concerning IA rupture. With the improved understanding of ML algorithms, clinicians’ trust in ML algorithms will be enhanced, accelerating their clinical translation

Large-Volume Blood Patch to Multiple Sites in the Epidural Space through a Single-Catheter Access Site for Treatment of Spontaneous Intracranial Hypotension

ABSTRACT BACKGROUND AND PURPOSE: Spontaneous intracranial hypotension can be a therapeutic challenge to the treating physician. In this study, we present our experience with the administration of a large-volume blood patch to multiple sites in the epidural space through a single-catheter access site

Successful Angioplasty of a Superficial Femoral Artery StenosisCaused by a Suture-Mediated Closure Device

We report the successful angioplasty of an acutearterial narrowing after suture-mediated closure (SMC) of a femoralarterial puncture. A 75-year-old woman underwent a cerebral arteriogramvia a right common femoral artery puncture. The arteriotomy site wasclosed with a SMC device. Four days after placement the patientcomplained of pain in her right calf after walking. An arteriogram 7days after SMC showed a severe focal stenosis at the origin of thesuperficial femoral artery involving the presumed puncture site. Thelesion was successfully treated with balloon angioplasty. The patientat 6 months was asymptomatic.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41325/1/270_2003_Article_2649.pd

Prone transradial catheterization for combined single-session endovascular and percutaneous interventions: approach, technical success, safety, and outcomes in 15 patients

PURPOSE:We aimed to report approach, safety, technical success, and clinical outcomes of prone trans- radial access (PTRA) and demonstrate feasibility for procedures requiring simultaneous arterial intervention and prone percutaneous access. METHODS:Fifteen patients underwent PTRA, seven females (47%) and eight males (53%), mean age of 55 years (range, 19–78 years). All patients underwent PTRA for combined transarterial and posterior-approach percutaneous interventions. Variables included sheath size (French, F), type of anesthesia, arterial intervention technical success, posterior-approach percutaneous intervention technical success, estimated blood loss (mL), fluoroscopy and procedure time, complications, and follow-up.RESULTS:Mean sheath size was 4 F (range, 4–6 F; SD = 0.5). Arterial interventions included transarterial embolization of renal (n=6), hepatic (n=2), and pelvic vessels (n=2), diagnostic arteriography (n=4), and embolization of an arteriovenous malformation (n=1). Posterior-approach intervention technical success was 100% (15/15). PTRA technical success was 100% (15/15). Posterior-approach percutaneous interventions included retroperitoneal (n=5) and pelvic (n=1) mass biopsies, nephrostomy tube placement (n=2), cryoablation of pelvic (n=2) and renal (n=1) masses, sclerotherapy of arteriovenous malformations (n=2), foreign body removal from the renal collecting system (n=2), ablation of a renal tumor (n=1), intracavitary injection of pulmonary mycetoma (n=1), and ablation and cementoplasty of a vertebral body tumor (n=1). The biopsies were diagnostic (6/6). There were no minor or major access-site complications.CONCLUSION:PTRA is a safe and feasible method for performing combined arterial and posterior approach percutaneous interventions without the need for repositioning

Gianturco Z-stent placement for the treatment of chronic central venous occlusive disease: implantation of 208 stents in 137 symptomatic patients

PURPOSETo report the technical successes, adverse events, and long-term stent patency rates of Gianturco Z-stents for management of chronic central venous occlusive disease.METHODSOverall, 137 patients, with mean age 48.6±16.1 years (range, 16-89 years), underwent placement of Gianturco Z-stents for chronic central venous occlusions. Presenting symptoms included lower extremity edema (n=66, 48.2%), superior vena cava syndrome (n=30, 21.9%), unilateral upper extremity swelling (n=20, 14.6%), hemodialysis fistula or catheter dysfunction (n=11, 8.0%), ascites (n=8, 5.8%), and both ascites and lower extremity edema (n=2, 1.5%). Most common etiologies of central venous occlusion were prior central venous access placement (n=58, 42.3%), extrinsic compression (n=29, 21.2%), and post-surgical anastomotic stenosis (n=27, 19.7%). Number of stents placed, stent implantation location, stent sizes, technical successes, adverse events, need for re-intervention, follow-up evaluation, stent patencies, and mortality were recorded. Technical success was defined as recanalization and stent reconstruction with restoration of in-line venous flow. Adverse events were defined by the Society of Interventional Radiology Adverse Event Classification criteria. Primary and primary-assisted stent patencies were analyzed using Kaplan-Meier analysis.RESULTSIn total, 208 Z-stents were placed. The three most common placement sites were the inferior vena cava (n=124, 59.6%), superior vena cava (n=44, 21.2%), and brachiocephalic veins (n=27, 13.0%). Technical success was achieved in 133 patients (97.1%). There were two (1.5%) severe adverse events (two cases of stent migration to the right atrium), one (0.7%) moderate adverse event, and one (0.7%) mild adverse event. Mean follow-up was 43.6±52.7 months. Estimated 1-, 3-, and 5-year primary stent patency was 84.2%, 84.2%, and 82.1%, respectively. Estimated 1-, 3-, and 5-year primary-assisted patency was 92.3%, 89.6%, and 89.6%, respectively. The 30- and 60- day mortality rates were 2.9% (n=4) and 5.1% (n=7), none of which were directly attributable to Z-stent placement.CONCLUSIONGianturco Z-stent placement is safe and effective for the treatment for chronic central venous occlusive disease with durable short- and long-term patencies