Head Phantom for the Acquisition of Pulsatile Optical Signals for Traumatic Brain Injury Monitoring

Roldán, María Teresa Milanés; Kyriacou, Panayiotis A.

doi:10.3390/photonics10050504

Cited by 4 publications

(1 citation statement)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Other techniques have been investigated to measure ICP non-invasively [11][12][13][14][15] . These include, Transcranial Doppler (TCD) based techniques [16][17][18][19][20][21] or the measurement of the Optic Nerve Sheet Diameter (ONSD) 22,23 .However, these devices involve cumbersome technology, are operatordependent, and may not provide direct and continuous measurement of ICP 24 .…”

Section: Introductionmentioning

confidence: 99%

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients

Roldán

Abay

Uff

et al. 2023

Preprint

View full text Add to dashboard Cite

Objective: In this research a non-invasive ICP optical sensor has been developed and evaluated in a clinical pilot study. The technology is based on infrared light interrogating brain tissue, including photodetectors used to detect the backscattered light, which is modulated by vascular pulsations in the brain vascular tissue. The hypothesis underpinning this research is based on the expected changes in the extramural arterial pressure affecting the morphology of the recorded optical signals (photoplethysmograms (PPGs)), therefore analysis of the acquired signals using a bespoke algorithm could enable the calculation of the intracranial pressure non-invasively (nICP). Methods: This pilot study is the first evaluation of the nICP probe in patients in whom the gold standard comparator of invasive ICP was available. nICP monitoring was performed for up to 48 hours in each of the 40 patients undergoing invasive ICP monitoring as part of their prescribed medical treatment. The quality of the recorded PPG signals was analysed, and time-based features were extracted off-line. Data from all ICP levels were randomly allocated into two groups to train (80%) and test (20%) a machine learning algorithm. A Bland Altman analysis and ROC curve were calculated to evaluate the accuracy of the estimated nICP value compared to the gold standard of synchronously acquired invasive ICP data. Results: The successful acquisition of cerebral PPG signals from TBI patients for the subsequent extraction of morphological features allowed the generation of a bagging tree model to estimate ICP non-invasively. The non-invasive estimation of ICP was achieved with 95% limits of agreement of 3.8 mmHg and a negligible bias. Furthermore, the model achieved a good correlation coefficient of 82.54% compared to standard clinical invasive ICP monitoring. Finally, the ROC curve analysis showed good diagnostic capability with a sensitivity of 80% and specificity of 89%. Conclusion: Clinical evaluation of this novel optical nICP sensor demonstrated for the first time that it could estimate ICP non-invasively to an acceptable and clinically useful accuracy and paves the way for further technology optimisation and larger clinical studies.

show abstract

Section: Introductionmentioning

confidence: 99%

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients

Roldán

Abay

Uff

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients

Roldan,

Abay,

Uff

et al. 2024

Acta Neurochir

Self Cite

View full text Add to dashboard Cite

Purpose In this research, a non-invasive intracranial pressure (nICP) optical sensor was developed and evaluated in a clinical pilot study. The technology relied on infrared light to probe brain tissue, using photodetectors to capture backscattered light modulated by vascular pulsations within the brain’s vascular tissue. The underlying hypothesis was that changes in extramural arterial pressure could affect the morphology of recorded optical signals (photoplethysmograms, or PPGs), and analysing these signals with a custom algorithm could enable the non-invasive calculation of intracranial pressure (nICP). Methods This pilot study was the first to evaluate the nICP probe alongside invasive ICP monitoring as a gold standard. nICP monitoring occurred in 40 patients undergoing invasive ICP monitoring, with data randomly split for machine learning. Quality PPG signals were extracted and analysed for time-based features. The study employed Bland–Altman analysis and ROC curve calculations to assess nICP accuracy compared to invasive ICP data. Results Successful acquisition of cerebral PPG signals from traumatic brain injury (TBI) patients allowed for the development of a bagging tree model to estimate nICP non-invasively. The nICP estimation exhibited 95% limits of agreement of 3.8 mmHg with minimal bias and a correlation of 0.8254 with invasive ICP monitoring. ROC curve analysis showed strong diagnostic capability with 80% sensitivity and 89% specificity. Conclusion The clinical evaluation of this innovative optical nICP sensor revealed its ability to estimate ICP non-invasively with acceptable and clinically useful accuracy. This breakthrough opens the door to further technological refinement and larger-scale clinical studies in the future. Trial registration NCT05632302, 11th November 2022, retrospectively registered.

show abstract

Evaluating the effectiveness of non-invasive intracranial pressure monitoring via near-infrared photoplethysmography using classical machine learning methods

Bradley,

Kyriacou

2024

Biomedical Signal Processing and Control

View full text Add to dashboard Cite

Head Phantom for the Acquisition of Pulsatile Optical Signals for Traumatic Brain Injury Monitoring

Cited by 4 publications

References 45 publications

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients

Evaluating the effectiveness of non-invasive intracranial pressure monitoring via near-infrared photoplethysmography using classical machine learning methods

Contact Info

Product

Resources

About