The guy in the image looks like he has had a significant trauma to his head that could have resulted in a skull fracture. Now the question is whether racoon eyes is more commonly associated with basilar skull # ( since most if you seem to have gone for basilar skull # ) or fracture of cranial vault. For a start, basilar skull fractures are less common ( 5 - 6 % ) than vault fractures ( approx - 95 % ) In case of Basilar skull # the periorbital ecchymosis is usually unilateral ( unless the fracture is bilateral ) and is associated with - Battle's sign - is ecchymosis of the mastoid process of the temporal bone. Cerebrospinal fluid rhinorrhea Cranial nerve palsy Bleeding from the nose and ears Hemotympanum conductive or perceptive deafness, nystagmus, vomitus In 1 to 10% of patients, optic nerve entrapment occurs:[SUP][/SUP]the optic nerve is pressed by the broken skull bones, causing irregularities in vision. Serious cases usually result in death In cranial vault fractures, the periorbital ecchymosis is usually bilateral ( typical racoon eyes ) and WHY is that so ? first a quick recall of the 5 layers of the scalp - 1) Skin 2) Dense subcutaneous tissue 3) Epicranius muscle and it's aponeurosis 4) Loose subaponeurotic tissue 5) Pericranium let's see what happens in a little detail with a cranial vault # - dura and pericranium tears --> blood from the intracranial hemorrhage communicates with the subaponeurotic space through the line of fracture --> even if the fracture is limited to one side, the blood will spread to both sides in the subaponeurotic space as this space does not respect laterality ( no midline partition ) ---> the blood in the subaponeurotic space, now slowly gravitates into the eyelids as the frontalis muscles has no bony atttachment ( usually to both eyelids, but more pronounced on the side of the # ). But is skull # the most common cause of racoon eyes ? Ans No Professional Boxers usually have black eyes 1 - 2 days following the end of an intense match. Is it because they have sustained a skull fracture ? Ans No It's usually because of the rupture of the emissary veins contained in the subaponeurotic space and the rest of the mechanism is same as explained for skull vault fracture. So my differentials in order of preference racoon eyes due to skull vault fracture racoon eyes due to basilar skull fracture Comments for or against are welcome (-: