Symptoms pointing to fracture of the Anterior Fossa.
Hæmorrhages:
(a) Subconjunctival hæmorrhage
usually makes its appearance at the outer canthus of the eye, progressing inwards towards the corneo-scleral margin, and, in the most severe cases, completely surrounding the cornea, bulging the conjunctiva forwards in such a manner as to constrict the field of vision. The extravasated blood is usually bright red in colour, makes its appearance within a few hours of the accident, and reaches its maximum within thirty-six to forty-eight hours.
In some cases a condition of subconjunctival œdema (chemosis) is observed. This also usually originates at the outer canthus.
Taken by themselves, neither hæmorrhage nor œdema are of any great diagnostic value. Both conditions, however, aid materially in confirming the diagnosis.
The blood is almost invariably completely absorbed, and no ill effects remain.
(b) Palpebral and peri-palpebral hæmorrhage
is seen in most cases of fracture of the anterior fossa. This form of hæmorrhage differs from the one mentioned above in that it usually commences at the inner canthus of the eye, thence progressing in the outward direction. The extravasated blood may be wholly anterior to the suspensory ligaments of the lid, in which case it may be surmised that the fracture only involves the perpendicular plate of the frontal bone. More commonly, however, the cribriform plate of the ethmoid shares in the lesion, in which case palpebral, peri-palpebral, and subconjunctival hæmorrhage are all present.