scholarly journals From head micro-motions towards CSF dynamics and non-invasive intracranial pressure monitoring

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Arnošt Mládek ◽  
Václav Gerla ◽  
Petr Šeba ◽  
Vladimír Kolář ◽  
Petr Skalický ◽  
...  
Keyword(s):  
Differential Geometry ◽  
Intracranial Pressure ◽  
Continuous Monitoring ◽  
Time Derivative ◽  
Global Perspective ◽  
Icp Monitoring ◽  
Csf Dynamics ◽  
Non Invasive ◽  
Cartan Curvature ◽  
Mechanical Sensors

AbstractContinuous monitoring of the intracranial pressure (ICP) is essential in neurocritical care. There are a variety of ICP monitoring systems currently available, with the intraventricular fluid filled catheter transducer currently representing the “gold standard”. As the placement of catheters is associated with the attendant risk of infection, hematoma formation, and seizures, there is a need for a reliable, non-invasive alternative. In the present study we suggest a unique theoretical framework based on differential geometry invariants of cranial micro-motions with the potential for continuous non-invasive ICP monitoring in conservative traumatic brain injury (TBI) treatment. As a proof of this concept, we have developed a pillow with embedded mechanical sensors and collected an extensive dataset (> 550 h on 24 TBI coma patients) of cranial micro-motions and the reference intraparenchymal ICP. From the multidimensional pulsatile curve we calculated the first Cartan curvature and constructed a ”fingerprint” image (Cartan map) associated with the cerebrospinal fluid (CSF) dynamics. The Cartan map features maxima bands corresponding to a pressure wave reflection corresponding to a detectable skull tremble. We give evidence for a statistically significant and patient-independent correlation between skull micro-motions and ICP time derivative. Our unique differential geometry-based method yields a broader and global perspective on intracranial CSF dynamics compared to rather local catheter-based measurement and has the potential for wider applications.

Effect of position on intracranial pressure and compliance: a cross-sectional study including 101 patients

2021 ◽  
pp. 1-9
Author(s):  
Linda D’Antona ◽  
Claudia Louise Craven ◽  
Fion Bremner ◽  
Manjit Singh Matharu ◽  
Lewis Thorne ◽  
...  
Keyword(s):  
Intracranial Pressure ◽  
Linear Regression ◽  
Regression Models ◽  
Cross Sectional Study ◽  
Icp Monitoring ◽  
Linear Regression Models ◽  
Sectional Study ◽  
Csf Dynamics ◽  
Cross Sectional ◽  
Intracranial Compliance

OBJECTIVE A better understanding of the effect of position on intracranial pressure (ICP) and compliance is important for the development of treatment strategies that can restore normal cerebrospinal fluid (CSF) dynamics. There is limited knowledge on the effect of position on intracranial compliance. In this cross-sectional study the authors tested the association of pulse amplitude (PA) with position and the day/night cycle. Additionally, they describe the postural ICP and PA changes of patients with “normal” ICP dynamics. METHODS This single-center retrospective study included patients with suspected and/or confirmed CSF dynamics abnormalities who had been examined with elective 24-hour ICP monitoring between October 2017 and September 2019. Patients had been enrolled in a short exercise battery including four positions: supine, lumbar puncture position in the left lateral decubitus position, sitting, and standing. Each position was maintained for 2 minutes, and mean ICP and PA were calculated for each position. The 24-hour day and night median ICP and PA data were also collected. Linear regression models were used to test the correlation of PA with position and day/night cycle. All linear regressions were corrected for confounders. The postural ICP monitoring results of patients without obvious ICP dynamics abnormality were summarized. RESULTS One hundred one patients (24 males and 77 females) with a mean age of 39 ± 13years (mean ± standard deviation) were included in the study. The adjusted linear regression models demonstrated a significant association of ICP with position and day/night cycle, with upright (sitting and standing) and day ICP values lower than supine and night ICP values. The adjusted linear regression model was also significant for the association of PA with position and day/night cycle, with upright and day PA values higher than supine and night PA results. These associations were confirmed for patients with and without shunts. Patients without clear ICP dynamics abnormality had tighter control of their postural ICP changes than the other patients; however, the difference among groups was not statistically significant. CONCLUSIONS This is the largest study investigating the effect of postural changes on intracranial compliance. The results of this study suggest that PA, as well as ICP, is significantly associated with posture, increasing in upright positions compared to that while supine. Further studies will be needed to investigate the mechanism behind this association.

scholarly journals Human ophthalmic artery as a sensor for non-invasive intracranial pressure monitoring: numerical modeling and in vivo pilot study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Paulius Lucinskas ◽  
Mantas Deimantavicius ◽  
Laimonas Bartusis ◽  
Rolandas Zakelis ◽  
Edgaras Misiulis ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Clinical Study ◽  
Intracranial Pressure ◽  
Pressure Sensor ◽  
Ophthalmic Artery ◽  
Open Angle Glaucoma ◽  
Icp Monitoring ◽  
Paired Data ◽  
Non Invasive ◽  
Data Points

AbstractIntracranial pressure (ICP) monitoring is important in managing neurosurgical, neurological, and ophthalmological patients with open-angle glaucoma. Non-invasive two-depth transcranial Doppler (TCD) technique is used in a novel method for ICP snapshot measurement that has been previously investigated prospectively, and the results showed clinically acceptable accuracy and precision. The aim of this study was to investigate possibility of using the ophthalmic artery (OA) as a pressure sensor for continuous ICP monitoring. First, numerical modeling was done to investigate the possibility, and then a pilot clinical study was conducted to compare two-depth TCD-based non-invasive ICP monitoring data with readings from an invasive Codman ICP microsensor from patients with severe traumatic brain injury. The numerical modeling showed that the systematic error of non-invasive ICP monitoring was < 1.0 mmHg after eliminating the intraorbital and blood pressure gradient. In a clinical study, a total of 1928 paired data points were collected, and the extreme data points of measured differences between invasive and non-invasive ICP were − 3.94 and 4.68 mmHg (95% CI − 2.55 to 2.72). The total mean and SD were 0.086 ± 1.34 mmHg, and the correlation coefficient was 0.94. The results show that the OA can be used as a linear natural pressure sensor and that it could potentially be possible to monitor the ICP for up to 1 h without recalibration.

scholarly journals Non-invasive intracranial pressure monitoring in idiopathic intracranial hypertension and lumbar puncture in pediatric patient: Case report

2021 ◽  
Vol 12 ◽  
pp. 493
Author(s):  
Thomas Markus Dhaese ◽  
Leonardo C. Welling ◽  
Alice Magro Kosciasnki ◽  
Gustavo Frigeri ◽  
Judy Auada ◽  
...  
Keyword(s):  
Case Report ◽  
Intracranial Pressure ◽  
Intracranial Hypertension ◽  
Lumbar Puncture ◽  
Idiopathic Intracranial Hypertension ◽  
Intracranial Pressure Monitoring ◽  
Invasive Technique ◽  
Icp Monitoring ◽  
Pressure Monitoring ◽  
Non Invasive

Background: Intracranial pressure (ICP) monitoring has been variously explored as a diagnostic and therapeutic modality in many pathological conditions leading neurological injury. This monitoring standardly depends on an invasive procedure such as cranial or lumbar catheterization. The gold standard for ICP monitoring is through an intraventricular catheter, but this invasive technique is associated with certain risks such as haemorrhage and infection. (1) Also, it is a high-cost procedure and consequently not available in a variety of underprivileged places and clinical situations in which intracranial hypertension is prevalent (3). An accurate non-invasive and low-priced method to measure elevated ICP would therefore be desirable. Under these circumstances, Brazilian scientists developed a non-invasive method for intracranial pressure monitoring (ICP-NI), which uses an electric resistance extensometer that measures micro deformations of the skull and transforms it into an electrical signal. In this case report, the authors describe a pediatrician patient with the diagnosis of idiopathic intracranial hypertension who was successfully submitted to a lumbar puncture under monitorization with this device. Case description: 7 year old girl with progressive symptoms that lead to the diagnosis of idiopathic intracranial hypertension. The patient was submitted to a lumbar punction with continuous non-invasive ICP monitoring. Conclusion: Estimating ICP (non-invasive) from LP monitoring (invasive) often reflect inaccurate ICP results, and affects negatively on IIH diagnosis and a non-invasive diagnostic method could reduce the requirement for invasive approaches, improving patient health outcomes.

scholarly journals Intracranial pressure monitoring

2015 ◽  
Vol 02 (03) ◽  
pp. 193-203 ◽  
Author(s):  
Mary Abraham ◽  
Vasudha Singhal
Keyword(s):  
Intracranial Pressure ◽  
Cost Effective ◽  
Optic Nerve Sheath Diameter ◽  
Icp Monitoring ◽  
Non Invasive ◽  
Injured Brain ◽  
Neurological Patients ◽  
Catheter Tip ◽  
Long Term Prognosis ◽  
Invasive Techniques

AbstractBrain specific monitoring enables detection and prevention of secondary cerebral insults, especially in the injured brain, thereby preventing permanent neurological damage. Intracranial pressure (ICP) monitoring is widely used in various neurological, neurosurgical and even medical conditions, both intraoperatively and in critical care, to improve patient outcome. It is especially useful in patients with traumatic brain injury, as a robust predictor of cerebral perfusion, and can help to guide therapy and assess long-term prognosis. Intraventricular catheters remain the gold standard for ICP monitoring, as they are the most reliable, accurate and cost-effective, and allow therapeutic cerebrospinal fluid drainage. Newer fibreoptic catheter tip and microchip transducer techniques have revolutionised ICP monitoring, with their ease of insertion in patients with narrow ventricles, and reduced risk of infection and haemorrhage. Furthermore, non-invasive methods of ICP monitoring, such as transcranial Doppler, optic nerve sheath diameter, etc., have emerged as promising techniques for screening patients with raised ICP in settings where invasive techniques are either not feasible (patients with severe coagulopathy) or not available (setups without access to a neurosurgeon). Therefore, ICP monitoring, as a part of multi-modality neuromonitoring, is a useful tool in the armamentarium of the neuro-intensivist in decreasing morbidity and mortality of critically ill neurological patients.

WP1-8 Radiographic markers of disturbances in CSF dynamics: correlating imaging with 24-hour ICP monitoring

2019 ◽  
Vol 90 (3) ◽  
pp. e3.3-e4
Author(s):  
H Asif ◽  
C Craven ◽  
L Thorne ◽  
L Watkins ◽  
A Toma
Keyword(s):  
Optic Nerve ◽  
Sella Turcica ◽  
Imaging Features ◽  
Imaging Findings ◽  
Icp Monitoring ◽  
Csf Dynamics ◽  
Non Invasive ◽  
Radiological Features ◽  
Nerve Sheath ◽  
The Mean

ObjectivesDisorders with chronically elevated ICP have salient imaging findings associated with the sella turcica and optic nerves. We aim to quantify the degree of correlation between imaging features and ICP.DesignProspective case-cohort study.SubjectsOne-hundred and twenty-six patients (35M:91F) underwent ICPM with recent MR imaging.MethodsT1-saggital views for sella volume, optic nerve vertical tortuosity, then T2-axial views for optic nerve sheath distension were blindly reviewed against respective median ICP and pulse amplitudes (PA). Imaging was triple reviewed for discordant values.ResultsThe mean ICP of four sella morphologies (full/flat/concave/empty) were 1.2, 4.8, 8.4 and 16.7 mmHg respectively (p<0.01). AUROC for sella morphology predicting ICP was 0.81. This measurement was able to detect minimum ICP of 5.3 mmHg with 73.0% sensitivity and specificity, 73.0% PPV and 69.8% NPV. The mean PA values were 4.0, 5.2, 6.1 and 9.6 mmHg respectively (p<0.01). AUROC for sella morphology predicting PA was 0.78. This measurement was able to detect minimum PA of 5.47 mmHg with 76.3% sensitivity, 79.5% specificity, 63.5% PPV and 81.0% NPV. Mean PA values for vertical tortuosity (nil/uni/bi) were 5.2, 7.1 and 7.0 mmHg respectively (p<0.05). Mean ICP values for rail tracking (nil/uni/bi) were 4.5, 7.5 and 15.7 mmHg respectively (p<0.01). Mean PA values were 5.2, 5.8 and 8.0 mmHg respectively (p<0.0001).ConclusionsCombined radiological features of ICP are promising non-invasive markers for raised ICP.

scholarly journals Wearable Intracranial Pressure Monitoring Sensor for Infants

Biosensors ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 213
Author(s):  
Baoyue Zhang ◽  
Ziyi Huang ◽  
Huixue Song ◽  
Hyun Soo Kim ◽  
Jaewon Park
Keyword(s):  
Intracranial Pressure ◽  
Continuous Monitoring ◽  
Low Cost ◽  
Ease Of Use ◽  
Flexible Polymers ◽  
Final Thickness ◽  
Non Invasive ◽  
Patients At Risk ◽  
Pressure Changes ◽  
Measured Pressure

Monitoring of intracranial pressure (ICP) is important for patients at risk of raised ICP, which may indicate developing diseases in brains that can lead to brain damage or even death. Monitoring ICP can be invaluable in the management of patients suffering from brain injury or hydrocephalus. To date, invasive measurements are still the standard method for monitoring ICP; however, these methods can not only cause bleeding or infection but are also very inconvenient to use, particularly for infants. Currently, none of the non-invasive methods can provide sufficient accuracy and ease of use while allowing continuous monitoring in routine clinical use at low cost. Here, we have developed a wearable, non-invasive ICP sensor that can be used like a band-aid. For the fabrication of the ICP sensor, a novel freeze casting method was developed to encapsulate the liquid metal microstructures within thin and flexible polymers. The final thickness of the ICP sensor demonstrated is 500 µm and can be further reduced. Three different designs of ICP sensors were tested under various pressure actuation conditions as well as different temperature environments, where the measured pressure changes were stable with the largest stability coefficient of variation being only CV = 0.0206. In addition, the sensor output values showed an extremely high linear correlation (R2 > 0.9990) with the applied pressures.

scholarly journals Non-invasive estimation of intracranial pressure by diffuse optics − a proof-of-concept study

2020 ◽  
Author(s):  
Jonas B Fischer ◽  
Ameer Ghouse ◽  
Susanna Tagliabue ◽  
Federica Maruccia ◽  
Anna Rey-Perez ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Intracranial Pressure ◽  
Correlation Coefficient ◽  
Correlation Spectroscopy ◽  
Critical Conditions ◽  
Proof Of Concept ◽  
Icp Monitoring ◽  
Concept Study ◽  
Non Invasive

Intracranial pressure (ICP) is an important parameter to monitor in several neuropathologies. However, because current clinically accepted methods are invasive, its monitoring is limited to patients in critical conditions. On the other side, there are other less critical conditions where ICP monitoring could still be useful, thus there is a need to develop non-invasive methods. We propose a new method to estimate ICP based on the analysis of the non-invasive measurement of pulsatile, microvascular cerebral blood flow with diffuse correlation spectroscopy. This is achieved by training a recurrent neural network using only the cerebral blood flow as the input. The method is validated using a 50% split sample method using the data from a proof-of-concept study. The study involved a population of infants (n=6) with external hydrocephalus (initially diagnosed as benign enlargement of subarachnoid spaces) as well as a population of adults (n=6) suffering from traumatic brain injury. The algorithm was applied to each cohort individually to obtain a model and an ICP estimate. In both diverse cohorts, the non-invasive estimation of ICP was achieved with an accuracy less than <4 mmHg and a negligible small bias. Furthermore, we have achieved a good correlation (Pearson's correlation coefficient >0.9) and good concordance (Lin's concordance correlation coefficient >0.9) in comparison to standard clinical, invasive ICP monitoring. This preliminary work paves the way for further investigations of this tool for the non-invasive, bed-side assessment of ICP.

scholarly journals Clinical review of non-invasive intracranial pressure measurement in medical cases

2016 ◽  
Vol 03 (01) ◽  
pp. 009-014 ◽  
Author(s):  
Shalini Nair
Keyword(s):  
Decision Making ◽  
Intracranial Pressure ◽  
Gold Standard ◽  
Surgical Intervention ◽  
Vital Role ◽  
Icp Monitoring ◽  
Neurological Emergencies ◽  
Non Invasive ◽  
Nerve Sheath ◽  
Invasive Techniques

AbstractIntracranial pressure (ICP) measurement plays a vital role in decision making in neurological emergencies. Invasive methods of ICP monitoring have been the gold standard. Advent of various non-invasive techniques has widened the option of ICP measurement in medical cases as well. We illustrate two cases where optic nerve sheath measurements helped in managing raised ICP and time the need for surgical intervention and review the literature on non-invasive ICP measurement.

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