Comparison of simultaneous continuous intracranial pressure (ICP) signals from ICP sensors placed within the brain parenchyma and the epidural space

2008 ◽  
Vol 30 (1) ◽  
pp. 34-40 ◽  
Author(s):  
Per Kristian Eide
2010 ◽  
Vol 113 (6) ◽  
pp. 1317-1325 ◽  
Author(s):  
Per Kristian Eide ◽  
Wilhelm Sorteberg

Object In this study, the authors compare simultaneous measurements of static and pulsatile pressure parameters in the epidural space and brain parenchyma of hydrocephalic patients. Methods Simultaneous intracranial pressure (ICP) signals from the epidural space (ICPEPI) and the brain parenchyma (ICPPAR) were compared in 12 patients undergoing continuous ICP monitoring as part of their diagnostic workup for hydrocephalus. The static ICP was characterized by mean ICP and the frequency of B waves quantified in the time domain, while the pulsatile ICP was determined from the cardiac beat–induced single ICP waves and expressed by the ICP pulse pressure amplitude (dP) and latency (dT; that is, rise time). Results The 12 patients underwent a median of 22.5 hours (range 5.9–24.8 hours) of ICP monitoring. Considering the total recording period of each patient, the mean ICP (static ICP) differed between the 2 compartments by ≥ 5 mm Hg in 8 patients (67%) and by ≥ 10 mm Hg in 4 patients (33%). In contrast, for every patient the ICP pulse pressure readings from the 2 compartments showed near-identical results. Consequently, when sorting patients to shunt/no shunt treatment according to pulsatile ICP values, selection was independent of sensor placement. The frequency of B waves also compared well between the 2 compartments. Conclusions The pulsatile ICP is measured with equal confidence from the ICPEPI and ICPPAR signals. When using the pulsatile ICP for evaluation of hydrocephalic patients, valid measurements may thus be obtained from pressure monitoring in the epidural space. Recorded differences in the mean ICP between the epidural space and the brain parenchyma are best explained by differences in the zero setting of different sensors.


2009 ◽  
Vol 111 (6) ◽  
pp. 1127-1130 ◽  
Author(s):  
Vicknes Waran ◽  
Narayanan Vairavan ◽  
Sheau Fung Sia ◽  
Basri Abdullah

The authors describe a newly developed expandable cannula to enable a more efficient use of an endoscope in removing intraparenchymal spontaneous hypertensive intracerebral hematomas. The cannula is introduced like a conventional brain cannula, using neuronavigation techniques to reach the targeted hematoma accurately, and, once deployed, conventional microsurgical techniques are used under direct endoscopic visualization. This method was used in 6 patients, and, based on the results of intraoperative intracranial pressure monitoring and postoperative CT scanning, the authors were able to achieve good hematoma removal. They found that by using the expandable cannula, efficient endoscopic surgery in the brain parenchyma was possible.


1987 ◽  
Vol 67 (2) ◽  
pp. 206-209 ◽  
Author(s):  
Richard C. Ostrup ◽  
Thomas G. Luerssen ◽  
Lawrence F. Marshall ◽  
Mark H. Zornow

✓ A No. 4 French fiberoptic catheter initially developed as an intravascular pressure sensor was incorporated into a system to be used as an intracranial pressure (ICP) monitor. Initially, a series of acute and chronic animal experiments carried out in the rabbit and pig, respectively, demonstrated the reliability and safety of the device. Subsequently, this new monitor was compared to a concurrently functioning ICP monitor in 15 adult and five pediatric patients. This clinical experience also confirmed the safety, accuracy, and reliability of the device. Since these initial studies, this monitor has been used to routinely measure ICP in a large number of adult and pediatric patients. The monitor has functioned well, and there have been no complications related to its use except for an occasional problem with breakage of the optic fiber as a result of patient movement or nursing maneuvers, which has been easily corrected by replacement of the probe. As nursing personnel and ancillary services have become familiar with this new monitor, breakage has not been a problem. This new device can be placed into the ventricular system, the brain parenchyma, or the subdural space, and appears to offer substantial advantages over other monitors presently in use.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Alice Buonfiglioli ◽  
Dolores Hambardzumyan

AbstractGlioblastoma (GBM) is the most aggressive and deadliest of the primary brain tumors, characterized by malignant growth, invasion into the brain parenchyma, and resistance to therapy. GBM is a heterogeneous disease characterized by high degrees of both inter- and intra-tumor heterogeneity. Another layer of complexity arises from the unique brain microenvironment in which GBM develops and grows. The GBM microenvironment consists of neoplastic and non-neoplastic cells. The most abundant non-neoplastic cells are those of the innate immune system, called tumor-associated macrophages (TAMs). TAMs constitute up to 40% of the tumor mass and consist of both brain-resident microglia and bone marrow-derived myeloid cells from the periphery. Although genetically stable, TAMs can change their expression profiles based upon the signals that they receive from tumor cells; therefore, heterogeneity in GBM creates heterogeneity in TAMs. By interacting with tumor cells and with the other non-neoplastic cells in the tumor microenvironment, TAMs promote tumor progression. Here, we review the origin, heterogeneity, and functional roles of TAMs. In addition, we discuss the prospects of therapeutically targeting TAMs alone or in combination with standard or newly-emerging GBM targeting therapies.


Author(s):  
F. Riva ◽  
T. Fracasso ◽  
A. Guerra ◽  
P. Genet

AbstractIn shooting crimes, ballistics tests are often recommended in order to reproduce the wound characteristics of the involved persons. For this purpose, several “simulants” can be used. However, despite the efforts in the research of “surrogates” in the field of forensic ballistic, the development of synthetic models needs still to be improved through a validation process based on specific real caseworks. This study has been triggered by the findings observed during the autopsy performed on two victims killed in the same shooting incident, with similar wounding characteristics; namely two retained head shots with ricochet against the interior wall of the skull; both projectiles have been recovered during the autopsies after migration in the brain parenchyma. The thickness of the different tissues and structures along the bullets trajectories as well as the incident angles between the bullets paths and the skull walls have been measured and reproduced during the assemblage of the synthetic head models. Two different types of models (“open shape” and “spherical”) have been assembled using leather, polyurethane and gelatine to simulate respectively skin, bone and soft tissues. Six shots have been performed in total. The results of the models have been compared to the findings of post-mortem computed tomography (PMCT) and the autopsy findings.Out of the six shots, two perforated the models and four were retained. When the projectile was retained, the use of both models allowed reproducing the wounds characteristics observed on both victims in terms of penetration and ricochet behaviour. However, the projectiles recovered from the models showed less deformation than the bullets collected during the autopsies. The “open shape” model allowed a better controlling on the shooting parameters than the “spherical” model. Finally, the difference in bullet deformation could be caused by the choice of the bone simulant, which might under-represent either the strength or the density of the human bone. In our opinion, it would be worth to develop a new, more representative material for ballistic which simulates the human bone.


2021 ◽  
pp. 1118-1123
Author(s):  
Kengo Setta ◽  
Takaaki Beppu ◽  
Yuichi Sato ◽  
Hiroaki Saura ◽  
Junichi Nomura ◽  
...  

Malignant lymphoma of the head rarely arises outside of the brain parenchyma as primary cranial vault lymphoma (PCVL). A case of PCVL that invaded from subcutaneous tissue into the brain, passing through the skull, and occurred after mild head trauma is reported along with a review of the literature. The patient was a 75-year-old man with decreased activity. One month before his visit to our hospital, he bruised the left frontal area of his head. Magnetic resonance imaging showed homogeneously enhanced tumors with contrast media in the subcutaneous tissue corresponding to the head impact area and the cerebral parenchyma, but no obvious abnormal findings in the skull. A biopsy with craniotomy was performed under general anesthesia. The pathological diagnosis was diffuse large B-cell lymphoma. On histological examination, tumor cells grew aggressively under the skin. Tumor cells invaded along the emissary vein into the external table without remarkable bone destruction and extended across the skull through the Haversian canals in the diploe. Tumor cells were found only at the perivascular areas in the dura mater and extended into the brain parenchyma. Considering the history of head trauma and the neuroimaging and histological findings, the PCVL in the present case arose primarily under the skin, passed though the skull and dura mater, and invaded along vessels and reached the brain.


Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 957
Author(s):  
Brad T. Casali ◽  
Erin G. Reed-Geaghan

Microglia are the resident immune cells of the brain, deriving from yolk sac progenitors that populate the brain parenchyma during development. During development and homeostasis, microglia play critical roles in synaptogenesis and synaptic plasticity, in addition to their primary role as immune sentinels. In aging and neurodegenerative diseases generally, and Alzheimer’s disease (AD) specifically, microglial function is altered in ways that significantly diverge from their homeostatic state, inducing a more detrimental inflammatory environment. In this review, we discuss the receptors, signaling, regulation and gene expression patterns of microglia that mediate their phenotype and function contributing to the inflammatory milieu of the AD brain, as well as strategies that target microglia to ameliorate the onset, progression and symptoms of AD.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii41-ii41
Author(s):  
Junjie Zhen ◽  
Lei Wen ◽  
Shaoqun Li ◽  
Mingyao Lai ◽  
Changguo Shan ◽  
...  

Abstract BACKGROUND According to EANO-ESMO clinical practice guidelines, the MRI findings of LM are divided into 4 types, namely linear enhancement (type A), nodular enhancement (type B), linear combined with nodular enhancement (type C), and sign of hydrocephalus (type D). METHODS The MRI features of brain and spinal cord in patients diagnosed with NSCLC-LM in Guangdong Sanjiu Brain Hospital from 2010 until 2019 were investigated, and then were classified into 4 types. The imaging features were analyzed. RESULTS A total of 80 patients were enrolled in the study. The median age of the patients was 53.5 years old, and the median time from the initial diagnosis to the confirmed diagnosis of LM was 11.6 months. The results of enhanced MRI examination of the brain in 79 cases showed that the number of cases with enhancements of type A, B, C and D were 50 (63.3%), 0, 26 (32.9%) and 3 (3.8%), respectively, and that LM with metastases to the brain parenchyma was found in 42 cases (53.2%). The results of enhanced MRI examination of spinal cord in 59 cases showed that there were only enhancements of type A and C in 40 cases (67.8%) and 3 cases (5.0%), and no enhancement sign in the other 16 cases (27.2%). CONCLUSION MRI examination of brain and spinal cord will improve the detection rate of LM. The MRI features of NSCLC-LM in real world are mainly characterized by the linear enhancements of brain and spinal cord, followed by linear combined with nodular enhancement. The enhancements of type B and type D are rare in clinic. Almost half of the patients have LM and metastases to the brain parenchyma. Therefore, the differentiation of tumor metastases is needed to be paid attention to for the early diagnosis and the formulation of reasonable treatment plans.


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