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Objectives:
Measurement of intracranial pressure (ICP) plays an important role in long-term monitoring and neuro-intensive treatment of patients with a cerebral shunt. Currently, only two complete telemetric implants with different technical features are available worldwide. This prospective pilot study aims to examine patients who had both probes...
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Objectives: Measurement of intracranial pressure (ICP) plays an important role in long-term monitoring and neuro-intensive treatment of patients with a cerebral shunt. Currently, only two complete telemetric implants with different technical features are available worldwide. This prospective pilot study aims to examine patients who had both probes...
Objectives: Measurement of intracranial pressure (ICP) plays an important role in long-term monitoring and neuro-intensive treatment of patients with a cerebral shunt. Currently, only two complete telemetric implants with different technical features are available worldwide. This prospective pilot study aims to examine patients who had both probes...
Citations
... Available technologies for ICP monitoring are made by a relatively small number of manufacturers. Each product or technology has its own benefits and weaknesses related to the technology itself or to the manufacturing process [11,13,30,41,[47][48][49][50]. ...
Traumatic brain injury (TBI) is a complex condition that requires specialized care. This chapter traces the history of TBI management from ancient times to the present day, revealing how medical knowledge and practice have advanced over the centuries. It covers the following topics:
The origins of TBI care in prehistoric cultures, where trepanation was performed to treat head injuries and release “evil spirits.”
The contributions of ancient civilizations, such as Egypt, Greece, and Rome, to the understanding of the brain, its functions, and its diseases. It highlights the role of Hippocrates who wrote the first treatise on head injuries and advocated for rational and humane treatment of TBI patients.
The discoveries of the Middle Ages and the Renaissance, such as the existence of cerebrospinal fluid (CSF), the concept of intracranial pressure (ICP), and the anatomy and physiology of the nervous system. It acknowledges the work of influential figures like Nicola Massa, Monro, Kellie, and Vesalius, who laid the groundwork for modern neuroscience.
The emergence of neurosurgery in the nineteenth and twentieth centuries, spurred by the challenges of wartime injuries and the development of new technologies, such as anesthesia and aseptic techniques. It discusses the case of Phineas Gage, who survived a penetrating brain injury and provided insights into brain localization. It also mentions the achievements of Harvey Cushing, the father of neurosurgery, and Santiago Ramon y Cajal, the founder of modern neurobiology.
The establishment of the Brain Trauma Foundation (BTF) in the late twentieth century, which produced evidence-based clinical practice guidelines for TBI management that have led to marked improvement in patient outcomes. It emphasizes the benefits of compliance with these guidelines and the need for ongoing research and education to further TBI care.
The evolution of neuromonitoring, which is a vital component of TBI care that allows for the direct assessment of brain physiology. It reviews the history of ICP monitoring, from the lumbar puncture technique first described by Heinrich Quincke in 1891 to the current invasive and noninvasive methods. It also introduces other neuromonitoring techniques, such as cerebral autoregulation and oxygenation monitoring that provide additional information on the brain’s status.
In summary, this chapter offers a comprehensive historical perspective on TBI management, highlighting the key events and people that shaped its progress and the role of neuromonitoring in modern neurocritical care. It provides a valuable context for understanding the current state of the art and the future directions of TBI care.
... The Neurovent-P-tel is a parenchymal sensor, while the Sensor Reservoir is connected to a ventricular catheter. Technical comparisons were previously published [2,14]. Both sensors are activated by an external reader unit (Reader TDT1 readP (Neurovent-P-tel) or Antenna (Sensor Reservoir)) and connected through a cable to an external storage unit (Datalogger (Neurovent-P-tel) or Reader Unit Set (Sensor Reservoir)). ...
... However, in our cohort, only two-thirds of the parents stated that a home monitoring session in fact reflected or partly reflected the child's everyday life, as the children were physically limited by the size and weight of external monitoring equipment and by the need for skin-fixation of the reader-ring. The external monitoring equipment from both Raumedic and Miethke has previously been reported as a disadvantage [4,14], and a new and smaller design has therefore also recently been launched from Raumedic (RAUMED Home ICP: size 140 × 72 × 16 mm and weight 200 gramme). ...
... This was supported by most of the children, regardless of age. The cosmetic disadvantage found in our cohort has previously been briefly reported for the Miethke Sensor Reservoir [14]. ...
Purpose
Telemetric monitoring of intracranial pressure (ICP) facilitates long-term measurements and home monitoring, thus potentially reducing diagnostic imaging and acute hospital admissions in favour of outpatient appointments. Especially in paediatric patients, telemetric ICP monitoring requires a high level of collaboration and compliance from patients and parents. In this study, we aim to systematically investigate (1) patient and parent perception of telemetric ICP system utility and (2) hospital contact history and thus the potential cost-benefit of telemetric ICP monitoring in paediatric patients with a cerebrospinal fluid disorder.
Methods
We conducted a nationwide questionnaire study, including paediatric patients with either a current or previous telemetric ICP sensor and their parents. Additionally, a retrospective review of electronic health records for all included children was performed.
Results
We included 16 children (age range 3–16 years), with a total of 41 telemetric ICP sensors implanted. Following sensor implantation, the frequency of telephone contacts and outpatient visits increased. No corresponding decrease in hospital admissions or total length of stay was found. The telemetric ICP sensor provided most parents with an improved sense of security and was seen as a necessary and valuable tool in treatment guidance. The size and shape of the sensor itself were reported as disadvantages, while the external monitoring equipment was reported as easy to use but too large and heavy for a child to carry.
Conclusion
Though, in quantitative terms, there was no cost-benefit of the telemetric ICP sensor, it contributed to extended parental involvement and a sense of improved safety.
... The Neurovent-P-tel is a parenchymal sensor, while the Sensor Reservoir is connected to a ventricular catheter. Technical comparisons are previously published [2,14]. Both sensors are activated by an external reader unit (Reader TDT1 readP (Neurovent-P-tel) or Antenna (Sensor Reservoir)) and connected through a cable to an external storage unit (Datalogger (Neurovent-P-tel) or Reader Unit Set (Sensor Reservoir)). ...
... However, in our cohort, only two thirds of the parents stated that a home monitoring session in fact re ected or partly re ected the child's everyday life, as the children were physically limited by the size and weight of external monitoring equipment, and by the need of skin-xation of the reader-ring. The external monitoring equipment from both Raumedic and Miethke has previously been reported as a disadvantage [4,14], and a new and smaller design has therefor also recently been launched from Raumedic (RAUMED Home ICP: size 140x72x16 mm and weight 200 gram). ...
... This was supported by most of the children, regardless of age. The cosmetic disadvantage found in our cohort has previous been brie y reported for the Miethke Sensor Reservoir [14]. ...
Purpose
Telemetric monitoring of intracranial pressure (ICP) facilitates long-term measurements and home-monitoring, thus potentially reducing diagnostic imaging and acute hospital admissions in favour of outpatient appointments. Especially in pediatric patients, telemetric ICP-monitoring requires a high level of collaboration and compliance from patients and parents. In this study, we aim to systematically investigate 1) patient- and parent perception of telemetric ICP system utility and 2) hospital contact history and thus potential cost-benefit of telemetric ICP monitoring in pediatric patients with a cerebrospinal fluid disorder.
Methods
We conducted a nationwide questionnaire study including pediatric patients with either a current or previous telemetric ICP sensor and their parents. Additionally, a retrospective review of electronic health records for all included children was performed.
Results
We included 16 children (age range 3-16 years), with a total of 41 telemetric ICP sensors implanted. Following sensor implantation, the frequency of telephone contacts and outpatient visits increased. No corresponding decrease in either hospital admissions or total length of stay was found.
The telemetric ICP sensor provided most parents with an improved sense of security and was seen as a necessary and valuable tool in treatment guidance. Size and shape of the sensor itself were reported as a disadvantage, while the external monitoring equipment was reported as easy to use, but too large and heavy for a child to carry.
Conclusion
Though, in quantitative terms, there was no cost-benefit of the telemetric ICP sensor, it contributes to an extended parental involvement and a sense of improved safety.
... Evaluation of IVP dynamics clearly demonstrated the influence of body position on CSF drainage in hydrocephalic human adults. [42][43][44][45][46][47] Higher CSF draining was associated with a standing position and the addition of the hydrostatic pressure in the shunt system to IVP that in sum act on the valve's resistance to CSF flow. 48,49 The use of shunts without antisiphoning devices is another major risk factor for overdrainage and hematoma in most human studies. ...
Background
Overshunting and hemispheric collapse are well‐known complications after ventriculoperitoneal shunt (VPS) implantation. Risk factors that predispose to overshunting, treatment options, and prognosis after therapeutic intervention have not been described.
Hypothesis/Objectives
To identify preoperative risk factors for overshunting, the effect of surgical decompression, and their outcomes.
Animals
Seventy‐five dogs and 7 cats.
Methods
Retrospective case cohort study. Age, breed, sex, body weight, number of dilated ventricles, ventricle brain ratio, intraventricular pressure, and implanted pressure valve systems were evaluated as possible risk factors.
Results
Overshunting had a prevalence of 18% (Cl 95% 9.9‐26.66). An increase of 0.05 in VBR increased the risk of overshunting by OR 2.23 (Cl 95% 1.4‐3.5; P = .001). Biventricular hydrocephalus had the highest risk for overshunting compared to a tri‐ (OR 2.48 with Cl 95% 0.5‐11.1) or tetraventricular hydrocephalus (OR 11.6 with Cl 95% 1.7‐81.1; P = .05). There was no influence regarding the use of gravitational vs differential pressure valves (P > .78). Overshunting resulted in hemispheric collapse, subdural hemorrhage, and peracute deterioration of neurological status in 15 animals. Subdural hematoma was removed in 8 dogs and 2 cats with prompt postoperative improvement of clinical signs.
Conclusions and Clinical Importance
Biventricular hydrocephalus and increased VBR indicate a higher risk for overshunting. The use of differential valves with gravitational units has no influence on occurrence of overshunting related complications and outcomes. Decompressive surgery provides a favorable treatment option for hemispheric collapse and has a good outcome.
... The current ICP minimally invasive monitoring methods, such as intraventricular ICP monitoring and epidural ICP monitoring, all need craniotomy. [4][5][6] The doctor needs to implant the pressure probe into the patient's brain, which leads to the high probability of complications, a high risk of infection, and high cost. Meanwhile, noninvasive monitoring methods for patients with craniocerebral injury are under study. ...
There is a lack of a safe and effective technology to monitor intracranial pressure accurately and non‐destructively. In this paper, the relationship between reduced scattering coefficient and intracranial pressure in clinical patients under different brain edema states was studied. First, the brain edema MC simulation model was constructed based on different types of brain edema. The results laid a foundation for clinical ICP detection. Second, the changes of ICP and reduced scattering coefficient caused by brain edema were studied in clinical application. It was found that when the patient developed brain edema, the reduced scattering coefficient and ICP showed corresponding changes. Finally, the mathematical model of invasive ICP and reduced scattering coefficient was established. It was found that the sensitivity of 834 nm light to brain tissue changes was higher than that of 692 nm light, which could be used to reflect the changes of brain tissue physiological state.
... This is a reservoir with a measuring cell inserted in line with the ventricular catheter proximal to the valve and allows non-invasive measurement of the ICP. The technology has high accuracy and reliability in recording ICP, and its purpose is to interrogate the shunt function and guide the adjustment of the valve [25]. However, the current literature on the interpretation of the data that this system provides is scarce [22]. ...
Background
The M.scio telesensor (Aesculap-Miethke, Germany) is a device integrated within a ventriculoperitoneal (VP) shunt for non-invasive measurement of the intracranial pressure (ICP). The purpose of this study was to analyze the telemetric recordings with the M.scio system in shunted patients with idiopathic intracranial hypertension (IIH), in order to determine reference values and assist the interpretation of telemetric data.
Methods
This was a cohort study of consecutive patients with fulminant IIH who underwent primary VP shunt insertion between July 2019 and June 2022. The first telemetric measurements after surgery in the sitting and supine positions were analyzed. Telemetric ICP values, wave morphology, and pulse amplitude were determined for functioning and malfunctioning shunts.
Results
Fifty-seven out of 64 patients had available telemetric recordings. The mean ICP was − 3.8 mmHg (standard deviation (SD) = 5.9) in the sitting and 16.4 mmHg (SD = 6.3) in the supine position. The ICP curve demonstrated pulsatility in 49 (86%) patients. A pulsatile curve with mean ICP in the above ranges indicated a functioning shunt, whereas the lack of pulsatility was challenging to interpret. There was a significant positive correlation between ICP versus amplitude, ICP versus body mass index (BMI), and amplitude versus BMI.
Conclusions
This clinical study defined ICP values and curves in IIH patients with a shunt. The results will assist the interpretation of telemetric ICP recordings in clinical decision making. More research is required to model longitudinal recordings and explore the link between telemetric measurements with clinical outcomes.
... Clinical studies of CSFP in cranium using telemetric methods in healthy and ill subjects also show such a phenomenon in humans. When changing the position of the body from supine to head-up position (sitting or standing), CSFP in the cranium always falls and takes a long-lasting negative (subatmospheric) value (Andresen et al., 2015;Ertl et al., 2017;Rot et al., 2020). ...
Interpersonal differences can be observed in the human cerebrospinal fluid pressure (CSFP) in the cranium in an upright body position, varying from positive to subatmospheric values. So far, these changes have been explained by the Monroe–Kellie doctrine according to which CSFP should increase or decrease if a change in at least one of the three intracranial volumes (brain, blood, and CSF) occurs. According to our hypothesis, changes in intracranial CSFP can occur without a change in the volume of intracranial fluids. To test this hypothesis, we alternately added and removed 100 or 200 μl of fluid from the spinal CSF space of four anesthetized cats and from a phantom which, by its dimensions and biophysical characteristics, imitates the cat cerebrospinal system, subsequently comparing CSFP changes in the cranium and spinal space in both horizontal and vertical positions. The phantom was made from a rigid “cranial” part with unchangeable volume, while the “spinal” part was made of elastic material whose modulus of elasticity was in the same order of magnitude as those of spinal dura. When a fluid volume (CSF or artificial CSF) was removed from the spinal space, both lumbar and cranial CSFP pressures decreased by 2.0–2.5 cm H 2 O for every extracted 100 μL. On the other hand, adding fluid volume to spinal space causes an increase in both lumbar and cranial CSFP pressures of 2.6–3.0 cm H 2 O for every added 100 μL. Results observed in cats and phantoms did not differ significantly. The presented results on cats and a phantom suggest that changes in the spinal CSF volume significantly affect the intracranial CSFP, but regardless of whether we added or removed the CSF volume, the hydrostatic pressure difference between the measuring sites (lateral ventricle and lumbar subarachnoid space) was always constant. These results suggest that intracranial CSFP can be increased or decreased without significant changes in the volume of intracranial fluids and that intracranial CSFP changes in accordance with the law of fluid mechanics.
... The manufacturer indicates a possible drift of < 2 mmHg in 4 years. A few reports have described the advantage of the system to be used also as "stand-alone" diagnostic tool offering ICP measurements and direct access to CSF for possible volume relieve [4][5][6][7]. ...
Introduction
Telemetric intracranial pressure measurement (tICPM) offers new opportunities to acquire objective information in shunted and non-shunted patients. The sensor reservoir (SR) provides tICPM modality at a decent sampling rate as an integrated component of the CSF shunt system. The aim of this study is to perform tICPM during a defined protocol of maneuvers in an outpatient setting as feasibility study including either shunt-dependent patients or candidates for possible shunt therapy.
Methods
A total of 17 patients received a SR and were investigated within a protocol of maneuver measurements involving different body postures (90°, 10°, 0°, and − 10°), breathing patterns (hypo- and hyperventilation), and mild venous congestion (Valsalva, Jugular vein compression), while the latter two were performed in lying postures (10° and 0°). The cohort included 11 shunted and 6 non-shunted (stand-alone-SR) patients. All measurements were evaluated using an ICP-analysis software (ICPicture, Miethke, Germany) looking at ICP changes and amplitude (AMP) characteristics.
Results
The shunted patient group consisted of 11 patients (median age: 15.8 years; range: 4–35.2 years) with either a primary shunt (n=9) and 2 patients received a shunt after stand-alone-SR tICPM. Six patients were enrolled with a stand-alone SR (median age 11.9 years, range 3.6–17.7 years). In the stand-alone SR group, maneuver related ICP and AMP changes were more sensitive compared to shunted patients. Postural maneuvers caused significant ICP changes in all body positions in both groups. The highest ICP values were seen during Valsalva maneuver, provoked by the patients themselves. In the stand-alone group, significant higher ICP values during hyperventilation were observed compared to shunted individuals. In shunted patients, a significant correlation between ICP and AMP was observed only during hyperventilation maneuver, while this correlation was additionally seen in Valsalva and jugular vein compression in stand-alone patients.
Conclusion
SR-related tICPM is helpful to objectify diagnostic evaluation in patients with CSF dynamic disturbances. The defined protocol did result in a wide range of ICP changes with promising potential for effective outpatient tICPM investigation. Since the correlation of ICP and AMP was observed during mild venous congestion maneuvers it appears to be specifically helpful for the evaluation of intracranial compliance. Further investigations of maneuver-related tICPM in a larger population, including variable pathologies, are needed to further establish the protocol in the clinical practice.
... The invasive ICP monitoring technology has the characteristics of accurate measurement and strong reliability, considered as the gold standard. 4,5 In clinical practice, the pressure sensor is placed under dura mater, ventricle or brain substance, and the doctor can directly achieve the pressure on the cranial cavity exerted by the contents of the cranial cavity. 6 However, after the pressure sensor probe is placed into brain tissue, long-term monitoring may cause cerebral hemorrhage or increase brain infection risk. ...
Intracranial hypertension is a serious threat to the health of neurosurgical patients. At present, there is a lack of a safe and effective technology to monitor intracranial pressure (ICP) accurately and nondestructively. In this paper, based on near infrared technology, the continuous nondestructive monitoring of ICP change caused by brain edema was studied. The rat brain edema models were constructed by lipopolysaccharide. The ICP monitor and the self-made near infrared tissue parameter measuring instrument were used to monitor the invasive intracranial pressure and the reduced scattering coefficient of brain tissue during the brain edema development. The results showed that there was a negative correlation between the reduced scattering coefficient (690nm and 834nm) and ICP, and then the mathematical model was established. The experimental results promoted the development of nondestructive ICP monitoring based on near infrared technology.
... First of all, compared to conventional ICP monitoring methods, it has the advantage of being a closed system decreasing the risk of infection [3,13]. This is particularly an argument for using the P-tel device for ICP monitoring in the neuro-intensive care setting which is usually the application field for cabled ICP probes [15,21]. ...
