Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Cerebral Edema l: Introduction01:19

Cerebral Edema l: Introduction

Cerebral edema is a pathological increase in brain water content that disrupts intracranial pressure regulation and impairs neurological function. Because the cranial vault is rigid, even modest increases in tissue volume can compromise cerebral perfusion, distort neural structures, and initiate secondary injury. Cerebral edema develops through four principal mechanisms: vasogenic, cytotoxic, interstitial, and ionic.Vasogenic EdemaVasogenic edema arises from disruption of the blood–brain...
Cerebral Edema ll: Pathophysiology01:22

Cerebral Edema ll: Pathophysiology

Vasogenic edema is a major form of cerebral edema characterized by abnormal accumulation of fluid in the brain’s extracellular space due to disruption of the blood–brain barrier (BBB). The BBB is a specialized structure composed of endothelial cells connected by tight junctions, supported by astrocytic endfeet and a basement membrane. Under normal conditions, it tightly regulates the movement of ions, proteins, and solutes between the bloodstream and brain parenchyma. When this barrier loses...
Increased Intracranial Pressure ll: Pathophysiology01:29

Increased Intracranial Pressure ll: Pathophysiology

Increased intracranial pressure (ICP) refers to a potentially life-threatening rise in pressure inside the skull. This usually happens when there is a major change in the volume of brain tissue, blood, or cerebrospinal fluid (CSF) — the three components inside the skull. According to the Monro-Kellie doctrine, if the volume of one component increases, the volumes of the other components must decrease to maintain normal pressure. If this does not happen, ICP rises.The process often begins with...
Increased Intracranial Pressure l: Introduction01:14

Increased Intracranial Pressure l: Introduction

Intracranial hypertension is a sustained elevation of intracranial pressure (ICP) above 22 mm Hg. In supine adults, normal ICP is ~7–15 mm Hg.The rigid, nonexpandable cranium contains three components—brain tissue, blood, and cerebrospinal fluid (CSF)—that total ~1,700 mL in a typical adult: 1,400 mL brain (~80%), 150 mL blood (~10%), and 150 mL CSF (~10%). According to the Monro–Kellie doctrine, total intracranial volume is effectively fixed. When one component expands, CSF and venous blood...
Cytotoxic Edema: Pathophysiology01:21

Cytotoxic Edema: Pathophysiology

Cytotoxic edema is a form of cerebral edema characterized by intracellular swelling of neurons, astrocytes, and other glial cells. It develops when the mechanisms responsible for maintaining ionic gradients across the cell membrane become impaired. Under normal physiological conditions, the sodium–potassium ATPase actively transports sodium ions out of the cell and potassium ions into the cell, preserving osmotic balance and enabling electrical signaling. This pump requires a continuous supply...
Specific Gravity of Aggregate01:19

Specific Gravity of Aggregate

Aggregates typically contain pores, which can be either permeable or impermeable. Considering the pores in the aggregates, the specific gravity of aggregates is defined in three different forms, namely, bulk or gross specific gravity, apparent specific gravity, and absolute specific gravity.
Bulk or gross specific gravity is calculated by taking the ratio of the mass of aggregates in the saturated surface-dry state to the total volume that includes both the solids and the voids within the...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Quantitative CT-scan to evaluate cerebral edema secondary to hyperammonemia in ICU: A proof-of-concept study.

Journal of intensive medicine·2026
Same author

Association of Socioeconomic Deprivation with 1-Year Functional Outcomes in Mechanically Ventilated Patients with Stroke.

Neurocritical care·2026
Same author

Tolerability and efficacy profile of S-ketamine compared with racemic ketamine in surgical patients, a prospective observational before-and-after study in the perioperative setting.

BJA open·2026
Same author

Neurological outcome of patients with a non-traumatic infratentorial cerebellar haematoma admitted to the intensive care unit.

Anaesthesia and intensive care·2026
Same author

Supratentorial Brain Lesions in Unconscious Patients Map to a Common Human Brain Circuit.

Annals of neurology·2026
Same author

Association between invasive intracranial pressure monitoring and 1-year functional outcome in ICU patients with severe stroke: a pre-planned ancillary study of the SPICE prospective cohort (SPICE-ICP).

Anaesthesia, critical care & pain medicine·2026

Related Experiment Video

Updated: Jun 30, 2026

Measuring Post-Stroke Cerebral Edema, Infarct Zone and Blood-Brain Barrier Breakdown in a Single Set of Rodent Brain Samples
04:32

Measuring Post-Stroke Cerebral Edema, Infarct Zone and Blood-Brain Barrier Breakdown in a Single Set of Rodent Brain Samples

Published on: October 23, 2020

Does brain swelling increase estimated specific gravity?

Vincent Degos1, Ana-Rosa Pereira, Thomas Lescot

  • 1Department of Anesthesiology and Critical Care, Pitié-Salpêtrière Teaching Hospital, Assistance Publique-Hôpitaux de Paris, Pierre and Marie Curie Paris 6 University, Paris, France.

Neurocritical Care
|September 27, 2008
PubMed
Summary
This summary is machine-generated.

Estimated brain specific gravity (eSG) was higher in severe traumatic brain injury (TBI) patients compared to those with subarachnoid hemorrhage (SAH). However, this increase in eSG is not caused by brain swelling in TBI.

More Related Videos

A Scalable Model to Study the Effects of Blunt-Force Injury in Adult Zebrafish
08:13

A Scalable Model to Study the Effects of Blunt-Force Injury in Adult Zebrafish

Published on: May 31, 2021

Quantitative Measurement of Intrathecally Synthesized Proteins in Mice
08:23

Quantitative Measurement of Intrathecally Synthesized Proteins in Mice

Published on: November 29, 2019

Related Experiment Videos

Last Updated: Jun 30, 2026

Measuring Post-Stroke Cerebral Edema, Infarct Zone and Blood-Brain Barrier Breakdown in a Single Set of Rodent Brain Samples
04:32

Measuring Post-Stroke Cerebral Edema, Infarct Zone and Blood-Brain Barrier Breakdown in a Single Set of Rodent Brain Samples

Published on: October 23, 2020

A Scalable Model to Study the Effects of Blunt-Force Injury in Adult Zebrafish
08:13

A Scalable Model to Study the Effects of Blunt-Force Injury in Adult Zebrafish

Published on: May 31, 2021

Quantitative Measurement of Intrathecally Synthesized Proteins in Mice
08:23

Quantitative Measurement of Intrathecally Synthesized Proteins in Mice

Published on: November 29, 2019

Area of Science:

  • Neurology
  • Radiology
  • Critical Care Medicine

Background:

  • Brain swelling is a significant factor in secondary neurological damage following traumatic brain injury (TBI).
  • Understanding the mechanisms of brain swelling is vital for improving TBI patient outcomes.
  • Previous research indicated a correlation between higher specific gravity (SG) and severe brain swelling in TBI patients.

Purpose of the Study:

  • To investigate the relationship between estimated specific gravity (eSG) and clinical indicators of brain swelling.
  • To determine if elevated eSG in TBI patients is directly linked to brain swelling.

Main Methods:

  • Retrospective analysis of prospectively collected data from a neurology intensive care unit.
  • Inclusion of 20 severe TBI patients, 20 high-grade subarachnoid hemorrhage (SAH) patients, 20 low-grade SAH patients, and 20 healthy controls.
  • Estimation of eSG from computed tomography (CT) images obtained at intensive care unit admission, focusing on overall intracerebral content and a white matter/diencephalon region of interest.

Main Results:

  • Estimated specific gravity (eSG) was significantly higher in the region of interest for severe TBI patients compared to high-grade SAH patients (1.0350 ± 0.0041 vs. 1.0310 ± 0.0019 g/ml, P < 0.05).
  • eSG values were comparable across the high-grade SAH, low-grade SAH, and control groups.
  • The study did not find a causal relationship between brain swelling and elevated eSG.

Conclusions:

  • The observed increase in eSG in severe TBI patients is not attributable to brain swelling.
  • Further research is needed to elucidate the underlying causes of elevated eSG in TBI.