ischemia

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Single photon emission computed tomography (SPECT) can be used to image blood flow to the heart (left) in order to monitor conditions such as ischemia (decreased blood flow). When information gathered via SPECT is combined with imaging information from computed tomography (CT), a fusion image (centre and right) can be obtained.

ischemia

pathology

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June 24, 2026

Quick Summary

Single photon emission computed tomography (SPECT) can be used to image blood flow to the heart (left) in order to monitor conditions such as ischemia (decreased blood flow). When information gathered via SPECT is combined with imaging information from computed tomography (CT), a fusion image (centre and right) can be obtained.

Ischemia is a condition characterized by a reduced supply of blood to an organ or part of the body, leading to a deficiency in oxygen and nutrients. This can cause damage to tissues and organs.

There are different types of ischemia:
* Ischemic stroke occurs when a blood vessel supplying the brain is narrowed or blocked, most commonly due to a blood clot.1
* Myocardial ischemia is a reduced blood supply to the heart muscle, which can be diagnosed using procedures like myocardial perfusion imaging.2
* Arteriolosclerosis can lead to ischemia by thickening the walls of small arteries, narrowing their passageways. This is often seen in individuals with diabetes or high blood pressure.3

When circulation is interrupted, it can disrupt nervous function, and if not restored quickly, can result in irreversible damage to neurons, creating an infarct.4

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apoptosis
Apoptosis in medicine
…damage resulting from episodes of ischemia in cardiac and neural tissue (ischemia is a reduction in blood flow to affected tissues). In addition, the selective control of apoptosis in the immune system can dramatically improve therapy for diseases from diabetes mellitus to HIV/AIDS. These opportunities and a basic curiosity about…
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…damage resulting from episodes of ischemia in cardiac and neural tissue (ischemia is a reduction in blood flow to affected tissues). In addition, the selective control of apoptosis in the immune system can dramatically improve therapy for diseases from diabetes mellitus to HIV/AIDS. These opportunities and a basic curiosity about…
Read More

arteriosclerosis
…of arteriolosclerosis can lead to ischemia, or insufficient blood flow to organs supplied by the blocked vessels. Arteriolosclerosis is most often seen in people who have diabetes mellitus or high blood pressure, though it is also a normal part of aging.
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…of arteriolosclerosis can lead to ischemia, or insufficient blood flow to organs supplied by the blocked vessels. Arteriolosclerosis is most often seen in people who have diabetes mellitus or high blood pressure, though it is also a normal part of aging.
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cardiovascular disease
Coronary heart disease
Ischemic heart disease, an alternative term, is actually more correct because the syndromes described are all to some degree manifestations of myocardial ischemia (a lack of blood supply to the myocardium, or heart muscle).
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Ischemic heart disease, an alternative term, is actually more correct because the syndromes described are all to some degree manifestations of myocardial ischemia (a lack of blood supply to the myocardium, or heart muscle).
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eye disease
Diabetes
…blood flow, a condition called ischemia, can also appear. Visual loss at this stage may be absent or caused by retinal swelling or ischemia. If unchecked, nonproliferative diabetic retinopathy can lead to worsened blood flow to the retina, more severe damage, and the appearance of new abnormal blood vessels on…
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…blood flow, a condition called ischemia, can also appear. Visual loss at this stage may be absent or caused by retinal swelling or ischemia. If unchecked, nonproliferative diabetic retinopathy can lead to worsened blood flow to the retina, more severe damage, and the appearance of new abnormal blood vessels on…
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renal system disease
Acute renal failure
…poor supply of blood (ischemia) has many causes, the most common and most important being multiple injuries, septicemia (infections invading the bloodstream), abortion with abnormal or excessive bleeding from the female genital tract, internal or external hemorrhage, loss of fluid from the body as in severe diarrhea or burns,…
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…poor supply of blood (ischemia) has many causes, the most common and most important being multiple injuries, septicemia (infections invading the bloodstream), abortion with abnormal or excessive bleeding from the female genital tract, internal or external hemorrhage, loss of fluid from the body as in severe diarrhea or burns,…
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nervous system disease
Clinical syndromes
…is one common sign of ischemia of the retina. Similar brief episodes of numbness or weakness of a limb or difficulty in speech suggest an attack in the carotid artery, while a brief reduction in consciousness, vertigo, slurred speech, impaired vision in both eyes, or imbalance may signify ischemia in…
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…is one common sign of ischemia of the retina. Similar brief episodes of numbness or weakness of a limb or difficulty in speech suggest an attack in the carotid artery, while a brief reduction in consciousness, vertigo, slurred speech, impaired vision in both eyes, or imbalance may signify ischemia in…
Read More