How do you interpret CT stroke perfusion?

How do you interpret CT stroke perfusion?

The key to interpreting CT perfusion in the setting of acute ischemic stroke is understanding and identifying the infarct core and the ischemic penumbra, as a patient with a small core and a large penumbra is most likely to benefit from reperfusion therapies.

What is mean transit time?

Definition. MTT is the average period of time that blood, or an element of blood such as a single red blood cell, spends within the blood vessels in a particular part of the brain. MTT is measured in seconds, and is typically on the order of 6 seconds in normal brain tissue (Mihara et al., 2003).

What is ischemic penumbra?

The ischemic penumbra was initially defined by Symon, Lassen and colleagues in the 1970s as an area of brain tissue with inadequate blood flow to maintain electric activity of neurons but adequate blood flow to preserve the function of the ion channels.

Does CT perfusion rule out stroke?

CT perfusion allows various aspects of cerebral perfusion to be determined. Its primary role in acute stroke is in determining whether brain tissue is hypoperfused and therefore at risk of infarction, or whether it is already irreversibly damaged. It can also make major contributions to diagnosis.

What is time to peak?

Time-to-peak (TTP) is the time at which contrast concentration reaches its maximum. For example, for a particular dynamic susceptibility contrast (DSC) imaging acquisition in which images are acquired every 1.5 seconds, possible TTP values could include 20.0 seconds, 21.5 seconds, 23.0 seconds, etc.

Which test provides the mean transit time for blood flow in the brain?

Positron emission tomography (PET) and dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI) are useful for the quantitative determination of MTT in the clinical setting.

What is CT perfusion?

Computed tomography (CT) perfusion imaging shows which areas of the brain are adequately supplied or perfused with blood and provides detailed information on delivery of blood or blood flow to the brain. CT perfusion scanning is a noninvasive medical test that helps physicians diagnose and treat medical conditions.

Why ischemic penumbra is important?

The ischemic penumbra refers to tissue at risk of infarction where perfusion is inadequate to support neuronal function, but just adequate to maintain cell viability (1).

How is ischemic penumbra treated?

Although treatments for ischemic stroke have been rigorously investigated for two decades, up to now there is only one FDA-approved pharmacological treatment for ischemic stroke, the intravenous thrombolytic treatment using recombinant tissue plasminogen activator (r-tPA).

How is a CTG used to monitor the fetal heart rate?

One transducer records the fetal heart rate using ultrasound and the other transducer monitors the contractions of the uterus by measuring the tension of the maternal abdominal wall (providing an indirect indication of intrauterine pressure). The CTG is then assessed by a midwife and the obstetric medical team. How to read a CTG

What is the purpose of a CTG scan?

It is most commonly used in the third trimester. Its purpose is to monitor fetal well-being and allow early detection of fetal distress. An abnormal CTG indicates the need for more invasive investigations and potentially emergency caesarian section.

What is cardiotocography (CTG)?

What is cardiotocography? Cardiotocography (CTG) is used during pregnancy to monitor the fetal heart and contractions of the uterus. It is most commonly used in the third trimester. Its purpose is to monitor fetal well-being and allow early detection of fetal distress.

How do you read a CTG?

How to Read a CTG | CTG Interpretation | Geeky Medics. Early deceleration. Early decelerations start when the uterine contraction begins and recover when uterine contraction stops. This is due to increased Variable deceleration. Late deceleration. Prolonged deceleration. Sinusoidal pattern.