Intraprocedural application of a peripheral blood flow monitoring system during endovascular treatment for femoropopliteal disease.

Sensors that implement laser speckle image streaming provide real-time, noninvasive assessment of peripheral blood flow during endovascular revascularization. This single-center feasibility study evaluated a laser speckle-based peripheral blood flow monitoring system in 24 patients with peripheral arterial disease. System-quantified blood flow values showed improvement at the conclusion of the procedure in 20 of 24 patients (83.3%). Of the four patients without improved flow values, waveform morphology improved in three. Waveforms graded as moderate to severe peripheral arterial disease decreased from 71% before the procedure to 25% after the procedure, with improvement in 19 of 24 patients. In this limited population, laser speckle imaging could offer a highly sensitive method of detecting intraprocedural pedal blood flow changes.

Psychological predictors of performance-based physical functioning among pediatric pain program participants.

PURPOSE: The purpose of the present study was to evaluate changes in performance-based physical functioning and investigate psychological predictors of physical functioning over time in pediatric patients with chronic pain who completed an interdisciplinary rehabilitation intensive outpatient program (IOP). METHODS: Participants (N = 55; mean age = 14.92 years; 12.7% male, 87.3% female; 83.6% White, 5.6% African-American/Black; 9.1% Latinx) completed baseline measures assessing pain intensity and modifiable psychological factors (i.e., pain catastrophizing, kinesiophobia, anxiety and depressive symptoms). Participants were administered performance-based assessments of physical functioning (i.e., physical endurance, high-level motor abilities) before and after IOP completion. RESULTS: Pain intensity was not significantly associated with physical functioning at either timepoint. There was significant improvement on measures of physical functioning after completion of the IOP when controlling for the effects of sex, race, and ethnicity. Depressive symptoms were associated with baseline physical endurance, ß = - .28, p = .047, while pain catastrophizing was associated with baseline gross motor abilities, ß = - .28, p = .032. CONCLUSION: Participation in an IOP led to significant improvement in physical endurance and high-level motor ability. Depressive symptoms and pain catastrophizing were associated with physical functioning at baseline but not post-program completion. Integration of pain psychology and physical therapy in an IOP can help address the interrelated psychological and physical factors impacting physical functioning to improve outcomes for children with chronic pain.

A Novel Tissue-Free Method to Estimate Tumor-Derived Cell-Free DNA Quantity Using Tumor Methylation Patterns.

Estimating the abundance of cell-free DNA (cfDNA) fragments shed from a tumor (i.e., circulating tumor DNA (ctDNA)) can approximate tumor burden, which has numerous clinical applications. We derived a novel, broadly applicable statistical method to quantify cancer-indicative methylation patterns within cfDNA to estimate ctDNA abundance, even at low levels. Our algorithm identified differentially methylated regions (DMRs) between a reference database of cancer tissue biopsy samples and cfDNA from individuals without cancer. Then, without utilizing matched tissue biopsy, counts of fragments matching the cancer-indicative hyper/hypo-methylated patterns within DMRs were used to determine a tumor methylated fraction (TMeF; a methylation-based quantification of the circulating tumor allele fraction and estimate of ctDNA abundance) for plasma samples. TMeF and small variant allele fraction (SVAF) estimates of the same cancer plasma samples were correlated (Spearman's correlation coefficient: 0.73), and synthetic dilutions to expected TMeF of 10-3 and 10-4 had estimated TMeF within two-fold for 95% and 77% of samples, respectively. TMeF increased with cancer stage and tumor size and inversely correlated with survival probability. Therefore, tumor-derived fragments in the cfDNA of patients with cancer can be leveraged to estimate ctDNA abundance without the need for a tumor biopsy, which may provide non-invasive clinical approximations of tumor burden.