Description
The ocular ultrasonography has evolved over years; the combined mode using A-scan and B-scan is very useful in the diagnosis of posterior segment pathology. Brightness mode helps in better evaluation of the mass lesion regarding their size, shape, extent and relationship with the remaining posterior segment structures. The frequency used for ophthalmic diagnosis is 8–10 MHz. The eyeball mainly encompasses the three coats: the sclera, choroid and retina. On B-scan, the normal spikes correspond to anterior lens capsule, posterior capsule, hypoechoic vitreous followed by the first high spike of the retina followed by the sclera. The retrobulbar fat is echogenic, and between this, the optic nerve can be seen as a tube-like hypoechoic channel extending from the sclera posteriorly towards the apex.12
Usual ocular scanning probe positions are transverse scan (gives the lateral extent of the lesion), longitudinal scan (gives the anteroposterior extent...
http://ift.tt/2kQKlBB
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου