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Computed tomography (CT scan): A CT scan may be normal if it is done soon after the onset of symptoms. A CT scan is the best test to look for bleeding in or around your brain. In some hospitals, a perfusion CT scan may be done to see where the blood is flowing and not flowing in your brain.
Magnetic resonance imaging (MRI scan): A special MRI technique (diffusion MRI) may show evidence of an ischemic stroke within minutes of symptom onset. In some hospitals, a perfusion MRI scan may be done to see where the blood is flowing and not flowing in your brain.
Angiogram: a test that looks at the blood vessels that feed the brain. An angiogram will show whether the blood vessel is blocked by a clot, the blood vessel is narrowed, or if there is an abnormality of a blood vessel known as an aneurysm.
Carotid duplex: A carotid duplex is an ultrasound study that assesses whether or not you have atherosclerosis (narrowing) of the carotid arteries. These arteries are the large blood vessels in your neck that feed your brain.
Transcranial Doppler (TCD): Transcranial Doppler is an ultrasound study that assesses whether or not you have atherosclerosis (narrowing) of the blood vessels inside of your brain. It can also be used to see if you have emboli (blood clots) in your blood vessels.
Antenatal corticosteroids have a role in reducing incidence of germinal matrix hemorrhage in premature infants.
Four grades are distinguished (by imaging or histology):
- grade I - hemorrhage is confined to the germinal matrix
- grade II - intraventricular hemorrhage without ventricular dilatation
- grade III - intraventricular hemorrhage with ventricular dilatation
- grade IV - intraventricular rupture and hemorrhage into the surrounding white matter
Lumbar puncture, in which cerebrospinal fluid (CSF) is removed from the subarachnoid space of the spinal canal using a hypodermic needle, shows evidence of hemorrhage in 3 percent of people in whom CT was found normal; lumbar puncture is therefore regarded as mandatory in people with suspected SAH if imaging is negative. At least three tubes of CSF are collected. If an elevated number of red blood cells is present equally in all bottles, this indicates a subarachnoid hemorrhage. If the number of cells decreases per bottle, it is more likely that it is due to damage to a small blood vessel during the procedure (known as a "traumatic tap"). While there is no official cutoff for red blood cells in the CSF no documented cases have occurred at less than "a few hundred cells" per high-powered field.
The CSF sample is also examined for xanthochromia—the yellow appearance of centrifugated fluid. This can be determined by spectrophotometry (measuring the absorption of particular wavelengths of light) or visual examination. It is unclear which method is superior. Xanthochromia remains a reliable ways to detect SAH several days after the onset of headache. An interval of at least 12 hours between the onset of the headache and lumbar puncture is required, as it takes several hours for the hemoglobin from the red blood cells to be metabolized into bilirubin.
After a subarachnoid hemorrhage is confirmed, its origin needs to be determined. If the bleeding is likely to have originated from an aneurysm (as determined by the CT scan appearance), the choice is between cerebral angiography (injecting radiocontrast through a catheter to the brain arteries) and CT angiography (visualizing blood vessels with radiocontrast on a CT scan) to identify aneurysms. Catheter angiography also offers the possibility of coiling an aneurysm (see below).
Intracerebral hemorrhages is a severe condition requiring prompt medical attention. Treatment goals include lifesaving interventions, supportive measures, and control of symptoms. Treatment depends on the location, extent, and cause of the bleeding. Often, treatment can reverse the damage that has been done.
A craniotomy is sometimes done to remove blood, abnormal blood vessels, or a tumor. Medications may be used to reduce swelling, prevent seizures, lower blood pressure, and control pain.
CT scan (computed tomography) is the definitive tool for accurate diagnosis of an intracranial hemorrhage. In difficult cases, a 3T-MRI scan can also be used.
When ICP is increased the heart rate may be decreased.
Treatment focuses on monitoring and should be accomplished with inpatient floor service for individuals responsive to commands or neurological ICU observation for those with impaired levels of consciousness. Extra attention should be placed on intracranial pressure (ICP) monitoring via an intraventricular catheter and medications to maintain ICP, blood pressure, and coagulation. In more severe cases an external ventricular drain may be required to maintain ICP and evacuate the hemorrhage, and in extreme cases an open craniotomy may be required. In cases of unilateral IVH with small intraparenchymal hemorrhage the combined method of stereotaxy and open craniotomy has produced promising results.
It is important that a person receive medical assessment, including a complete neurological examination, after any head trauma. A CT scan or MRI scan will usually detect significant subdural hematomas.
Subdural hematomas occur most often around the tops and sides of the frontal and parietal lobes. They also occur in the posterior cranial fossa, and near the falx cerebri and tentorium cerebelli. Unlike epidural hematomas, which cannot expand past the sutures of the skull, subdural hematomas can expand along the inside of the skull, creating a concave shape that follows the curve of the brain, stopping only at the dural reflections like the tentorium cerebelli and falx cerebri.
On a CT scan, subdural hematomas are classically crescent-shaped, with a concave surface away from the skull. However, they can have a convex appearance, especially in the early stage of bleeding. This may cause difficulty in distinguishing between subdural and epidural hemorrhages. A more reliable indicator of subdural hemorrhage is its involvement of a larger portion of the cerebral hemisphere since it can cross suture lines, unlike an epidural hemorrhage. Subdural blood can also be seen as a layering density along the tentorium cerebelli. This can be a chronic, stable process, since the feeding system is low-pressure. In such cases, subtle signs of bleeding such as effacement of sulci or medial displacement of the junction between gray matter and white matter may be apparent. A chronic bleed can be the same density as brain tissue (called isodense to brain), meaning that it will show up on CT scan as the same shade as brain tissue, potentially obscuring the finding.
Treatment of a subdural hematoma depends on its size and rate of growth. Some small subdural hematomas can be managed by careful monitoring until the body heals itself. Other small subdural hematomas can be managed by inserting a temporary small catheter through a hole drilled through the skull and sucking out the hematoma; this procedure can be done at the bedside. Large or symptomatic hematomas require a craniotomy, the surgical opening of the skull. A surgeon then opens the dura, removes the blood clot with suction or irrigation, and identifies and controls sites of bleeding. Postoperative complications include increased intracranial pressure, brain edema, new or recurrent bleeding, infection, and seizure. The injured vessels must be repaired.
Depending on the size and deterioration, age of the patient, and anaesthetic risk posed, subdural hematomas occasionally require craniotomy for evacuation; most frequently, simple burr holes for drainage; often conservative treatment; and rarely, palliative treatment in patients of extreme age or with no chance of recovery.
In those with a chronic subdural hematoma, but without a history of seizures, the evidence is unclear if using anticonvulsants is harmful or beneficial.
Symptoms of IVH are similar to other intracerebral hemorrhages and include sudden onset of headache, nausea and vomiting, together with an alteration
of the mental state and/or level of consciousness. Focal neurological signs are either minimal or absent, but focal and/or generalized seizures may occur. Xanthochromia, yellow-tinged CSF, is the rule. Diagnosis can be confirmed by the presence of blood inside the ventricles on CT.
A "subarachnoid hemorrhage" is bleeding into the subarachnoid space—the area between the arachnoid membrane and the pia mater surrounding the brain. Besides from head injury, it may occur spontaneously, usually from a ruptured cerebral aneurysm. Symptoms of SAH include a severe headache with a rapid onset ("thunderclap headache"), vomiting, confusion or a lowered level of consciousness, and sometimes seizures. The diagnosis is generally confirmed with a CT scan of the head, or occasionally by lumbar puncture. Treatment is by prompt neurosurgery or radiologically guided interventions with medications and other treatments to help prevent recurrence of the bleeding and complications. Since the 1990s, many aneurysms are treated by a minimal invasive procedure called "coiling", which is carried out by instrumentation through large blood vessels. However, this procedure has higher recurrence rates than the more invasive craniotomy with clipping.
Diagnostic methods include:
- Angiogram
Due to positive remodeling the plaque build-up shown on angiogram may appear further downstream on the x-ray where the luminal diameter would look normal even though there is severe narrowing at the real site. Because angiograms require x-rays to be visualized the number of times an individual can have it done over a year is limited by the guidelines for the amount of radiation they can be exposed to in a one-year period.
- Magnetic resonance imaging (MRI)
Magnetic resonance imaging has the ability to quantify the plaque anatomy and composition. This allows physicians to determine certain characteristics of the plaque such as how likely it is to break away from the wall and become an embolus. MRI does not use ionizing radiation, so the number of times that it is used on a single person is not a concern; however since it uses strong electric fields those who have metal implants in cannot use this technique.
- Computed tomography (CT)
Multidirectional computed tomography (MDCT) is better than regular CT scans, because it can provide a higher spatial resolution and it has a shorter acquisition time. MDCT uses x-rays to obtain the image; however it can identify the composition of the plaque. Thus it can be determined whether the plaque is calcified plaque and lipid-rich plaque, so the inherent risks can be determined. Subjects are exposed to a substantial amount of radiation with this procedure, so their use is limited.
The most important initial investigation is computed tomography of the brain, which is very sensitive for subarachnoid hemorrhage. If this is normal, a lumbar puncture is performed, as a small proportion of SAH is missed on CT and can still be detected as xanthochromia.
If both investigations are normal, the specific description of the headache and the presence of other abnormalities may prompt further tests, usually involving magnetic resonance imaging (MRI). Magnetic resonance angiography (MRA) may be useful in identifying problems with the arteries (such as dissection), and magnetic resonance venography (MRV) identifies venous thrombosis. It is not usually necessary to proceed to cerebral angiography, a more precise but invasive investigation of the brain's blood vessels, if MRA and MRV are normal.
Diagnosis is confirmed with CT, or bedside ultrasound for less stable patients. Exploratory laparotomy is rarely used, though it may be of benefit in patients with particularly severe hemorrhage. A set of CT scan grading criteria was created to identify the need for intervention (surgery or embolization) in patients with splenic injury. The criteria were established using 20 CT scans from a database of hemodynamically stable patients with blunt splenic injury. These criteria were then validated in 56 consecutive patients retrospectively and appear to reliably predict the need for invasive management in patients with blunt injury to the spleen (sensitivity of 100%, specificity 88%, overall accuracy was 93%).
The study suggested that the following three CT findings correlate with the need for intervention:
1. Devascularization or laceration involving 50% or more of the splenic parenchyma
2. Contrast blush greater than one centimeter in diameter (from active extravasation of IV contrast or pseudoaneurysm formation)
3. A large hemoperitoneum.
If a small amount of bleeding is seen in early pregnancy a physician may request:
- A quantitative human chorionic gonadotropin (hCG) blood test to confirm the pregnancy or assist in diagnosing a potential miscarriage
- Transvaginal pelvic ultrasonography to confirm that the pregnancy is not outside of the uterus
- Blood type and Rh test to rule out hemolytic disease of the newborn
For bleeding seen in later pregnancy tests may include:
- Complete blood count (CBC) and blood type and screen
- Ultrasound to determine placental location
- Kleihauer-Betke (KB) test especially if there was maternal trauma
Diagnosis of cerebrovascular disease is done by (among other diagnoses):
- clinical history
- physical exam
- neurological examination.
It is important to differentiate the symptoms caused by a stroke from those caused by syncope (fainting) which is also a reduction in cerebral blood flow, almost always generalized, but they are usually caused by systemic hypotension of various origins: cardiac arrhythmias, myocardial infarction, hemorrhagic shock, among others.
Prognostics factors:
Lower Glasgow coma scale score, higher pulse rate, higher respiratory rate and lower arterial oxygen saturation level is prognostic features of in-hospital mortality rate in acute ischemic stroke.
Pregnant patients may have bleeding from the reproductive tract due to trauma, including sexual trauma, neoplasm, most commonly cervical cancer, and hematologic disorders. Molar pregnancy (also called hydatiform mole) is a type of pregnancy where the sperm and the egg have joined within the uterus, but the result is a cyst resembling a grape-like cluster rather than an embryo. Bleeding can be an early sign of this tumor developing.
Treatment has traditionally been splenectomy. However, splenectomy is avoided if possible, particularly in children, to avoid the resulting permanent susceptibility to bacterial infections. Most small, and some moderate-sized lacerations in stable patients (particularly children) are managed with hospital observation and sometimes transfusion rather than surgery. Embolization, blocking off of the hemorrhaging vessels, is a newer and less invasive treatment. When surgery is needed, the spleen can be surgically repaired in a few cases, but splenectomy is still the primary surgical treatment, and has the highest success rate of all treatments.
In an ischemic stroke, blood supply to part of the brain is decreased, leading to dysfunction of the brain tissue in that area. There are four reasons why this might happen:
1. Thrombosis (obstruction of a blood vessel by a blood clot forming locally)
2. Embolism (obstruction due to an embolus from elsewhere in the body, see below),
3. Systemic hypoperfusion (general decrease in blood supply, e.g., in shock)
4. Venous thrombosis.
Stroke without an obvious explanation is termed "cryptogenic" (of unknown origin); this constitutes 30-40% of all ischemic strokes.
Asymptomatic individuals with intracranial stenosis are typically told to take over the counter platelet inhibitors like aspirin whereas those with symptomatic presentation are prescribed anti-coagulation medications. For asymptomatic persons the idea is to stop the buildup of plaque from continuing. They are not experiencing symptoms; however if more build up occurs it is likely they will. For symptomatic individuals it is necessary to try and reduce the amount of stenosis. The anti-coagulation medications reduce the likelihood of further buildup while also trying to break down the current build up on the surface without an embolism forming. For those with severe stenosis that are at risk for impending stroke endovascular treatment is used. Depending on the individual and the location of the stenosis there are multiple treatments that can be undertaken. These include angioplasty, stent insertion, or bypass the blocked area.
Treatment varies according to severity, ranging from monitoring of the hematoma (in haemodynamic stability) to emergency surgery (when patients develop hypovolemic shock requiring seminephrectomy or nephrectomy). Vascular causes lead to surgery due to severity of hemorrhage. Robotic-assisted partial nephrectomy has been proposed as a surgical treatment of a ruptured angiomyolipoma causing retroperitoneal hemorrhage, combining the advantages of a kidney preservation procedure and the benefits of a minimally invasive procedure without compromising the safety of the patient.
Wunderlich syndrome is spontaneous, nontraumatic renal hemorrhage confined to the subcapsular and perirenal space. It may be the first manifestation of a renal angiomyolipoma (AML), or rupture of renal artery or intraparechymal aneurysm.
Intracranial hemorrhage is the accumulation of blood anywhere within the skull vault. A distinction is made between intra-axial hemorrhage (blood inside the brain) and extra-axial hemorrhage (blood inside the skull but outside the brain). Intra-axial hemorrhage is due to intraparenchymal hemorrhage or intraventricular hemorrhage (blood in the ventricular system). The main types of extra-axial hemorrhage are epidural hematoma (bleeding between the dura mater and the skull), subdural hematoma (in the subdural space) and subarachnoid hemorrhage (between the arachnoid mater and pia mater). Most of the hemorrhagic stroke syndromes have specific symptoms (e.g., headache, previous head injury).