Patient Risk Factors Associated With 30- and 90-Day Readmission After Ventriculoperitoneal Shunt Placement for Idiopathic Normal Pressure Hydrocephalus in Elderly Patients: A Nationwide Readmission Study.

OBJECTIVE: For idiopathic normal pressure hydrocephalus (iNPH), risk stratifying patients and identifying those who are likely to fare well after ventriculoperitoneal shunt (VP) surgery may help improve quality of care and reduce unplanned readmissions. The aim of this study was to investigate the drivers of 30- and 90-day readmissions after VP shunt surgery for iNPH in elderly patients. METHODS: The Nationwide Readmission Database, years 2013 to 2015, was queried. Elderly patients (≥65 years old) undergoing VP shunt surgery were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification coding system. Unique patient linkage numbers were used to follow patients and identify 30- and 31- to 90-day readmission rates. Patients were grouped by no readmission (Non-R), readmission within 30 days (30-R), and readmission within 31 to 90 days (90-R). RESULTS: We identified 7199 elderly patients undergoing VP shunt surgery for iNPH. A total of 1413 (19.6%) patients were readmitted (30-R: n = 812 [11.3%] vs. 90-R: n = 601 [8.3%] vs. Non-R: n = 5786). The most prevalent 30- and 90-day complications seen among the readmitted cohort were mechanical complication of nervous system device implant (30-R: 16.1%, 90-R: 12.4%), extracranial postoperative infection (30-R: 10.4%, 90-R: 7.0%), and subdural hemorrhage (30-R: 6.0%, 90-R: 16.4%). On multivariate regression analysis, age, diabetes, and renal failure were independently associated with 30-day readmission; female sex, and 26th to 50th household income percentile were independently associated with reduced likelihood of 90-day readmission. Having any complication during the index admission independently associated with both 30- and 90-day readmission. CONCLUSIONS: In this study, we identify the most common drivers for readmission for elderly patients with iNPH undergoing VP shunt surgery.

Dynamic contrast-enhanced and dynamic susceptibility contrast perfusion MR imaging for glioma grading: Preliminary comparison of vessel compartment and permeability parameters using hotspot and histogram analysis.

INTRODUCTION: Dynamic susceptibility contrast (DSC)-MRI is a perfusion technique with high diagnostic accuracy for glioma grading, despite limitations due to inherent susceptibility effects. Dynamic contrast-enhanced (DCE)-MRI has been proposed as an alternative technique able to overcome the DSC-MRI shortcomings. This pilot study aimed at comparing the diagnostic accuracy of DSC and DCE-MRI for glioma grading by evaluating two estimates of blood volume, the DCE-derived plasma volume (Vp) and the DSC-derived relative cerebral blood volume (rCBV), and a measure of vessel permeability, the DCE-derived volume transfer constant K(trans). METHODS: Twenty-six newly diagnosed glioma patients underwent 3T-MR DCE and DSC imaging. Parametric maps of CBV, Vp and K(trans) were calculated and the region of highest value (hotspot) was measured on each map. Histograms of rCBV, Vp and K(trans) values were calculated for the tumor volume. Statistical differences according to WHO grade were assessed. The diagnostic accuracy for tumor grading of the two techniques was determined by ROC analysis. RESULTS: rCBV, Vp and K(trans) measures differed significantly between high and low-grade gliomas. Hotspot analysis showed the highest correlation with grading. K(trans) hotspots co-localized with Vp hotspots only in 56% of enhancing gliomas. For differentiating high from low-grade gliomas the AUC was 0.987 for rCBVmax, and 1.000 for Vpmax and K(trans)max. Combination of DCE-derived Vp and K(trans) parameters improved the diagnostic performance of the histogram method. CONCLUSION: This initial experience of DCE-derived Vp evaluation shows that this parameter is as accurate as the well-established DSC-derived rCBV for glioma grading. DCE-derived K(trans) is equally useful for grading, providing different informations with respect to Vp.