12 imaging signs you must know about cerebral hemorrhage!

In recent years, many studies have shown that some specific imaging signs in plain CT and CTA can predict the expansion of cerebral hemorrhage hematoma.

1.

• Density similar to brain parenchyma with clear boundaries
• Density similar to brain parenchyma but ill-defined
• Density similar to edema or cerebrospinal fluid
• Uneven density and presence of liquid level

Intrahematoma low density was an independent risk factor for hematoma expansion (OR=3.

2.

A: Irregular black hole sign, 35 HU difference from the HU value of the surrounding hematoma; B: round black hole sign; C: strip black hole sign, the low-density area in the hematoma separated from the brain tissue; D: small round black hole

The sensitivity, specificity, positive predictive value, and negative predictive value of the black hole sign were 33%, 94%, 73%, and 73%, respectively

3.

ac showed three distinct swirl signs, i.

4.

 A and B are confounding signs, and there is an obvious demarcation between the two density areas; C has no obvious demarcation; D is a vortex sign in which the high-density area completely wraps the low-density area

The mechanism of its formation is that the coagulated blood clot in the hematoma shows high density on CT, while the low density area may be due to the continuous bleeding of the ruptured blood vessel , and the blood has not yet coagulated

5.

A: In patients with basal ganglia hemorrhage, 3 scattered small hematomas can be seen, each separated from the main hematoma; B: In patients with putamen hemorrhage, 3 independent small hematomas can be seen, note the low level between the small hematoma and the main hematoma Signal area; C: In patients with lobar hemorrhage, 4 scattered small hematomas were seen D: In patients with basal ganglia hemorrhage and protrusion into the ventricle, 4 small vesicular or budding hematomas were seen connected to the main hematoma, and a separate Scattered small hematoma

The reason for its formation may be that with the expansion of the hematoma, the adjacent arterioles are damaged, causing the appearance of small islands around the main hematoma
.
The study showed that the sensitivity, specificity, positive and negative predictive values ​​of "island sign" in predicting hematoma expansion were 44.
7%, 98.
2%, 92.
7%, and 77.
7%, respectively
.
Therefore, it can be used as a reliable indicator for predicting early hematoma expansion in patients with ICH, and is an independent risk factor for poor prognosis at 90 days (OR=3.
51, 95%CI: 1.
26-9.
81)
.

6.
Satellite sign

Proposed by Shimoda et al.
, is an independent predictor of the prognosis of intracerebral hemorrhage
.
Defined as:
there is a small hematoma separated from the main hematoma on at least one level;
the largest diameter of the small hematoma is <10 mm;
the minimum distance of the small hematoma from the main hematoma is 1-20 mm;

Subarachnoid hematoma and intraventricular hematoma were excluded
.

7.
Inhomogeneous hematoma density and irregular shape of hematoma

Barras et al reported for the first time the imaging predictive value of hematoma shape and density under CT scan for hematoma expansion, and divided it into 5 types according to the shape and density of hematoma
.
As shown below (shape classification on the left, density classification on the right):

 8.
Liquid level

Recent studies have also found that fluid levels are associated with hematoma expansion and poor prognosis
.
The appearance of this sign may reflect abnormalities in the hemorrhagic coagulation process, which results in early high-density protein deposits
.
Fluid levels are rare in patients with bleeding, and their incidence has been reported to be about 1% to 7% in the past
.

Combining the above non-enhanced CT signs, some scholars suggested that the hematoma with a tendency to expand, that is, one or more of the mixed sign, black hole sign and island sign were positive, which was the hematoma enlargement (OR=28.
33, 95%CI: 12.
95~61.
98) and a strong predictor of poor prognosis (OR=5.
67, 95%CI: 2.
82-11.
40)
.

1.
Point sign

In 2007, Canadian scholars first proposed the point sign, which is defined as:

At least 1 contrast medium concentration appears at the site of contrast medium extravasation in the intracranial hematoma
.

Peripheral hematoma with a CT measurement of at least 120HU compared to its density

Adjacent, discontinuous, normal or abnormal blood vessels surrounding the hematoma

The dot sign exists within the scope of the intracranial hematoma
.

The high-risk patients with hematoma expansion can be identified by the point sign.
The sensitivity, specificity, positive and negative predictive values ​​of the CTA point sign in predicting hematoma expansion were 63%, 90%, 73%, and 84%, respectively
.
And the more high-density "spots", the higher the risk of hematoma expansion
.

In addition, the spot sign is associated with poor prognosis, early clinical deterioration, high mortality, and intraventricular hemorrhage, and is considered one of the most reliable predictors of early hematoma expansion and poor prognosis
.

However, in clinical practice, it is necessary to be alert to false-positive conditions such as aneurysm, small arteriovenous malformation, moyamoya disease, tumor and choroid plexus calcification
.

Then the point sign score is proposed:

• The number of enhanced spots: 1~2 points for 1 point, ≥3 points for 2 points
• The maximum diameter of the shaft: 0 points for 1~4mm, 1 point for ≥5mm
• Maximum CT value: 0 points for 120~179HU, 1 point for ≥180HU

The spot sign score was the strongest independent risk factor for hematoma expansion, suggesting that the number and morphological indicators of enhancing spots were associated with the risk of hematoma expansion
.
In addition, the point sign score also has predictive value for in-hospital death and poor 3-month prognosis
.

2.
Leak sign

Japanese scholars proposed to compare the original CTA image in the arterial phase and the delayed phase to determine a region of interest with a diameter of 10 mm on the delayed phase image.
positive
.
The sensitivity and specificity for predicting hematoma expansion were 93.
3% and 88.
9%
.

3.
Iodine sign

It was proposed by Chinese scholars that the diagnostic criteria of positive iodine sign on the original image of CTA by gemstone energy spectrum imaging technology synthesis map are: ≥ 1 enhanced spot in the hematoma and the spot needs to be clearly visible to the naked eye, and the iodine concentration in the spot needs to be > 7.
82 ( 100ug/ml) and the spots are not located in the area of ​​normal blood vessels
.

The iodine sign independently predicted hematoma expansion (OR=53.
67, 95%CI: 11.
88-242.
42), and had higher sensitivity (91.
5% vs 63.
8%) and accuracy (85.
7% vs 75.
8%) than the point sign
.

4.
Congestion sign

Proposed by a Singaporean scholar, it refers to the leakage of contrast medium larger than 1mm*2mm in the hematoma, and it is in the shape of a curved nozzle
.
The results suggested that hyperemia was an independent risk factor for hematoma expansion (OR=6.
05, 95%CI: 1.
03-15.
95) and death (OR=3.
31, 95%CI: 1.
24-25.
41)
.