From Spot Sign to Bleeding on the Spot: Classic and Original Signs of Expanding Primary Spontaneous Intracerebral Hematoma

Table 1

Signs of hematoma heterogeneity or in predicting its expansion.

Signs	Imaging modality	Author	Definition
Flood phenomenon	MRI	First reported in the current article	Increase in the size of the intracranial hematoma between the first and last MRI sequences during the same examination
Margin irregularity	NCCT or CTA	Blacquiere et al. [7]	Indicates bleeding multifocality
Mean CT attenuation value	NCCT	Chu et al. [12]	If <31 UH, it indicates an impaired coagulation and higher risk of expansion
Extension into the ventricles	NCCT or CTA	Deng et al. [13]	The parenchymal bleed dissects into the ventricles
Spot sign	Enhanced CT	Demchuk et al. [4]	>1.5 mm dot-like appearance without connection to an outside vessel or corresponding density on NCCT twice as dense as the remaining hematoma
Blend sign	NCCT	Li et al. [14]	The mixture of the fresh central hyperdense blood with the older peripheral blood
Black hole sign	NCCT or CTA	Li et al. [15]	Central hypodense streaming blood encapsulated within the hyperdense coagulating hematoma (minimum of 28 HU difference between both)
Island sign	NCCT or CTA	Li et al. [16]	Either at least 3 small hematomas totally separate from the main focus or 4 small foci that may bud from the initial hematoma
Satellite sign	NCCT or CTA	Shimoda et al. [17]	Single small , completely isolated from the initial bleed
Swirl sign	NCCT	Boulouis et al. [18]	Hypodense area found on 2 consecutive 5 mm axial CT slices
Leakage sign	Contrast-enhanced CT between arterial and delayed phase	Koculym et al. [19]	A 10% increase in the density of the hematoma over a region of interest of 1 cm diameter between the arterial and the delayed phase