Parkinson's Disease (PD) is a clinically diagnosed neurodegenerative disorder that affects both motor and non-motor neural circuits. Speech deterioration (hypokinetic dysarthria) is a common symptom, ...which often presents early in the disease course. Machine learning can help movement disorders specialists improve their diagnostic accuracy using non-invasive and inexpensive voice recordings.
We used "Parkinson Dataset with Replicated Acoustic Features Data Set" from the UCI-Machine Learning repository. The dataset included 44 speech-test based acoustic features from patients with PD and controls. We analyzed the data using various machine learning algorithms including Light and Extreme Gradient Boosting, Random Forest, Support Vector Machines, K-nearest neighborhood, Least Absolute Shrinkage and Selection Operator Regression, as well as logistic regression. We also implemented a variable importance analysis to identify important variables classifying patients with PD.
The cohort included a total of 80 subjects: 40 patients with PD (55% men) and 40 controls (67.5% men). Disease duration was 5 years or less for all subjects, with a mean Unified Parkinson's Disease Rating Scale (UPDRS) score of 19.6 (SD 8.1), and none were taking PD medication. The mean age for PD subjects and controls was 69.6 (SD 7.8) and 66.4 (SD 8.4), respectively. Our best-performing model used Light Gradient Boosting to provide an AUC of 0.951 with 95% confidence interval 0.946-0.955 in 4-fold cross validation using only seven acoustic features.
Machine learning can accurately detect Parkinson's disease using an inexpensive and non-invasive voice recording. Light Gradient Boosting outperformed other machine learning algorithms. Such approaches could be used to inexpensively screen large patient populations for Parkinson's disease.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The theoretical advantages of hybrid constructs over multi-level fusion have been illustrated in clinical and biomechanical studies. However, there is no biomechanical data on hybrid constructs using ...load control analyses. There is also no clear data on whether there is a biomechanical difference if the arthroplasty is below or above a 1- or 2-level fusion. This work investigated the effect on segmental motion of having a cervical total disc arthroplasty implanted above or below a 1- or 2-level fusion.
Segmental motions of 16 C2-T1 cervical spine specimens were measured as the specimens were tested to 1.5Nm in axial rotation and in flexion-extension under compressive preload. Tests were conducted on intact specimens, and then after arthroplasty with a 1-level and 2-level fusion. 8 specimens were in test Group 1, where the hybrid configuration had a total disc arthroplasty above a 1- or 2-level fusion. The arthroplasty was below the 1- and 2-level fusion in Group 2. Load control and displacement control analyses were conducted to determine the effect of the hybrid configurations on segmental motion.
In load control, compensatory motion increases were found at all non-instrumented cervical spine segments in flexion-extension and axial rotation. Flexion-extension and axial rotation ranges of motion at the total disc arthroplasty level were less than 1° different than intact.
In displacement control, there was no consistent pattern of compensatory motion. Range of motion at the arthroplasty level was within 3.5° of intact.
The total disc arthroplasty segmental level in a hybrid construct has similar amounts of motion as intact. This may shield the arthroplasty level and adjacent levels from supra-physiological motion and loading. These results suggest that a hybrid construct may be protective of adjacent segments, whether the total disc arthroplasty is above or below the fusion.
While saccular abdominal aortic aneurysms (AAAs) are thought to be more prone to rupture than fusiform aneurysms, attempts to validate this observation have been limited by the inability to ...quantitatively define the three-dimensional shape of an aorta. A quantitative three-dimensional shape model may distinguish among shape classes and ultimately be useful in identifying aneurysms at risk for rupture. Three-dimensional luminal surface data of AAAs were generated from computed tomographic (CT) images of 15 patients with small aneurysms (< or =5.5 cm maximal transverse diameter). The centerline was used to construct a shape classification based upon the orthographic projection of the centerline about its central axis. The extent and direction of the individual deviations were quantified as areas on the plane of projection to create a shape classification. Hierarchical cluster analysis was used to verify distinct shape classes. A tortuosity index was calculated as a function of the centerline projection. AAA shape was calculated as a tortuosity index and classified into distinct classes of minimal or increased three-dimensional tortuosity. Thrombus could change the tortuosity index or shape classification of an aneurysm. In several patients with serial CT scans, the tortuosity index changed over time and was correlated with rupture; in three AAAs that ruptured the mean tortuosity increased 29% whereas the mean transverse diameter increased 3.3%. Expanding AAAs develop specific, quantifiable shapes that can be expressed as a quantitative tortuosity index that may be relevant to their natural history. The three-dimensional features of this shape model provide a novel and potentially clinically relevant adjunct to maximal transverse diameter. Larger studies are needed to correlate the tortuosity index with finite element models and the ability to predict aneurysm rupture.
ABSTRACT
INTRODUCTION
Morphologic features of computed tomography (CT) scans of the brain can be used to estimate intracranial pressure (ICP) via an image‐processing algorithm. Clinically, such ...estimations can be used to prognosticate outcomes and avoid placement of invasive intracranial monitors in certain patients with severe traumatic brain injury. Features on a CT scan that may correlate with measurements of low ICP are sought.
METHODS
A measure is proposed that is a function of the distribution of cerebrospinal fluid (CSF) in and around the brain. In our method, we present an algorithm that semiautomatically segments brain parenchyma from CSF, and apply standard image processing calculations. The ratio of CSF volume to the size of the intracranial vault (ICV) or volume inside the skull, csfv/icvv is calculated and then plotted against the actual recorded ICP, yielding a relationship between the image features and ICP.
RESULTS
We analyzed a total of 45 scans from 20 patients with severe traumatic brain injury (TBI). We showed that a ratio csfv/icvv > .034 correlates with an ICP < 20 mmHg (P = .0046). For csfv/icvv ≤ .034, a distinction between low and high ICP cannot be effectively estimated by this univariate measure.
CONCLUSION
This method permits a noninvasive means of identifying patients who are low risk for having elevated ICP; by following Brain Trauma Foundation guidelines strictly such a patient may be subjected to an unnecessary, invasive procedure. This work is a promising pilot study that will need to be analyzed for a larger population.
Hyperemia in the infarcted brain has been -suggested for years by "red veins" reported by neurosurgeons, shunt peaks in radioactive blood flow clearance curves, and quantitative cerebral blood flow ...using stable xenon CT. Histological characterization of infarcted brain revealed capillary rarefaction with prominent microvascular shunts (MVS). Despite abundant histological evidence, the presence of cerebrovascular shunts have been largely ignored, perhaps because of a lack of physiological evidence demonstrating the transition from capillary flow to MVS flow. Our studies have shown that high intracranial pressure induces a transition from capillary to microvascular shunt flow resulting in cerebral hypoperfusion, tissue hypoxia and brain edema, which could be delayed by increasing cerebral perfusion pressure. The transition from capillary to microvascular shunt flow provides for the first time a physiological basis for evaluating the optimal cerebral perfusion pressure with increased intracranial pressure. It also provides a physiological basis for evaluating the effectiveness of various drugs and therapies in reducing intracranial pressure and the development of brain edema and tissue hypoxia after brain injury and ischemia. In summary, the clear-cut demonstration of the transition from capillary to MVS flow provides an important method for evaluating various therapies for the treatment of brain edema and loss of autoregulation.
INTRODUCTION Long segment lumbosacral spinal fusions are a common treatment modality for patients diagnosed with spinal deformity. Complication rates and fusion rates regarding obese patients ...undergoing these surgeries is not well defined. METHODS A retrospective chart review was performed on patients undergoing long segment lumbosacral fusion from at least L3 to sacrum that also had pelvic fixation placed (either S2AI or iliac bolt) from 2017–2019. Baseline demographic data, operative time and blood loss, fluoroscopy time, postoperative complications, lumbar lordosis, and implant failure rates were recorded. Patients with BMI greater than 30 were compared to patients with a BMI less than 30. RESULTS There were 184 patients identified. 94 patients met criteria for obesity (51%). Smoking rates were 23% and not significantly different between the two groups. Postoperative complication rates were 45% and not different between the two groups. The most common complication was ileus (11% of patients). Implant failures (15%) and reoperations (15%) were not significantly different. Preoperative lumbar lordosis was higher in obese patients (40.6 degrees obese patients, 32.1 degrees non-obese patients, P = .039). Postoperative change in lordosis was less in obese patients than non-obese patients (9 degrees obese patients, 16 degrees non-obese patients, P = .006). CONCLUSION Long segment lumbosacral fusions with pelvic fixation are extensive and challenging cases with high complication rates. Obese patients in our cohort do not have higher complication rates, implant failures, or reoperation rates. Patients should not be ruled out for surgical treatment on BMI alone.
Abstract only
The P2X purinoceptor 4 (P2X4) plays a crucial role in signaling leading to chronic inflammatory and neuropathic pains, thus, the P2X4 receptor provides a new potential therapeutic ...target for their treatment. We have generated a panel of mouse single‐chain Fv‐antibodies (scFvs) recognizing extracellular peptide of P2X4 using cell‐free ribosome display, for use to pain‐signalling neurons. A mouse scFv library was generated, and ribosome display was applied for anti‐P2X4 scFv recombinant antibody selection. After three rounds of bio‐panning, a panel of recombinant antibodies was isolated followed by ELISA, cross reactivity analysis, western blotting and immunofluorescence staining. Anti‐P2X4 scFv clones with high specificity and affinity were successfully selected. Indirect ELISA assay revealed differential P2X4 peptide binding capability and specificity for three scFvs, with no reaction to the negative control anti‐Zika scFv 7‐2. The panning process was efficient in selecting clones of high affinity, as was evident from affinity differences of the scFvs: scFv95 and scFv12 had the highest and second highest affinities, respectively, while scFv103 had lower affinity. The highest affinity P2X4 receptor scFvs (12 and 95) were selected for
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) Model. Single dose intraperitoneal injection (4 mg/kg, 100 μl) reversed mechanical allodynia and anxiety in mice with long standing neuropathic pain (8–10 weeks). Reversal to naïve baseline within one week was maintained for more than 10 weeks post‐treatment at experiment end. Continued reversal was maintained at baseline for >20 weeks in a second cohort. The Western blot of the medullary brainstem provides evidence of brain penetration of both these scFv antibodies that reduce hypersensitivity and anxiety behaviors. We also performed whole‐cell patch clamp recordings from dissociated trigeminal ganglia neurons of nerve‐injured vs naïve mice and determined the effect of P2X4 receptor scFvs on neuronal excitability. These data provide support for pursuit of P2X4 receptor scFvs as translational therapy for pain relief.
Support or Funding Information
1. GRANT FUNDING NIH NIDCR R21 DE028096 2. Start‐up Funds to Dr. Durvasula 3. Startup Funds to Dr. Westlund
To develop and validate a noninvasive imaging technique for accurately assessing very slow CSF flow within shunt tubes in pediatric patients with hydrocephalus, aiming to identify obstructions that ...might impede CSF drainage.
A simulation of shunt flow enhancement of signal intensity (shunt-FENSI) signal is used to establish the relationship between signal change and flow rate. The quantification of flow enhancement of signal intensity data involves normalization, curve fitting, and calibration to match simulated data. Additionally, a phase sweep method is introduced to accommodate the impact of magnetic field inhomogeneity on the flow measurement. The method is tested in flow phantoms, healthy adults, intensive care unit patients with external ventricular drains (EVD), and shunt patients. EVDs enable shunt-flow measurements to be acquired with a ground truth measure of CSF drainage.
The flow-rate-to-signal simulation establishes signal-flow relationships and takes into account the T
of draining fluid. The phase sweep method accurately accounts for phase accumulation due to frequency offsets at the shunt. Results in phantom and healthy human participants reveal reliable quantification of flow rates using controlled flows and agreement with the flow simulation. EVD patients display reliable measures of flow rates. Shunt patient results demonstrate feasibility of the method and consistent flow rates for functional shunts.
The results demonstrate the technique's applicability, accuracy, and potential for diagnosing and noninvasively monitoring hydrocephalus. Limitations of the current approach include a high sensitivity to motion and strict requirement of imaging slice prescription.
Women neurosurgeons (WNs) continue to remain a minority in the specialty despite significant initiatives to increase their representation. One domain less explored is the regional distribution of ...WNs, facilitated by the hiring practices of neurosurgical departments across the US. In this analysis, the authors coupled the stated practice location of WNs with regional geospatial data to identify hot spots and cold spots of prevalence and examined regional predictors of increases and decreases in WNs over time.
The authors examined the National Provider Identifier (NPI) numbers of all neurosurgeons obtained via the National Plan and Provider Enumeration System (NPPES), identifying the percentage of WNs in each county for which data were appended with data from the US Census Bureau. Change in WN rates was identified by calculating a regression slope for all years included (2015-2022). Hot spots and cold spots of WNs were identified through Moran's clustering analysis. Population and surgeon features were compared for hot spots and cold spots.
WNs constituted 10.73% of all currently active neurosurgical NPIs, which has increased from 2015 (8.81%). Three hot spots were found-including the Middle Atlantic and Pacific divisions-that contrasted with scattered cold spots throughout the East Central regions that included Memphis as a major city. Although relatively rapidly growing, hot spots had significant gender inequality, with a median WN percentage of 11.38% and a median of 0.61 WNs added to each respective county per year.
The authors analyzed the prevalence of WNs by using aggregated data from the NPPES and US Census Bureau. The authors also show regional hot spots of WNs and that the establishment of WNs in a region is a predictor of additional WNs entering the region. These data suggest that female neurosurgical mentorship and representation may be a major driver of acceptance and further gender diversity in a given region.
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