Pediatric Radiology > Neurological > Head Ultrasound > Germinal Matrix Hemorrhage


Germinal Matrix Hemorrhage Grade 1

The germinal matrix is the stem source for neuroblasts and is a fetal structure only. It typically involutes by term but is still present in premature infants. The germinal matrix is very vascular and is prone to hemorrhage. It lies within the caudothalamic groove, which is the space between the caudate nucleus head and the thalamus. Hemorrhage is seen as echogenic material within the caudothalamic groove. Choroid plexus is also echogenic and care should be made not to misinterpret choroid for hemorrhage; normal choroid plexus does not extend anterior to the caudothalamic groove on the parasagittal views. Germinal matrix hemorrhage is classified into four grades, I-IV. Grade IV hemorrhage is thought to be a venous infarction hemorrhage rather than direct extension from the germinal matrix.

   
Grade I Hemorrhage confined to germinal matrix
Grade II Intraventricular hemorrhage without ventricular dilatation
Grade III Intraventricular hemorrhage with ventricular dilatation
Grade IV Intraparenchymal hemorrhage

   
Coronal, Grade I with hyperechoic hemorrhage in caudothalamic groove
   
Coronal, Grade I hemorrhage showing evolution to cystic changes
   
Sagittal, Hyperechoic hemorrhage in caudothalamic groove
   
Sagittal, Grade I hemorrhage showing evolution to cystic changes