Computed Tomography for Diagnosis of Persistent Hyperplastic Primary Vitreous (PHPV)

Leucocoric eyes with persistent hyperplastic primary vitreous (PHPV) were studied by computed tomography (CT). Maximum information was derived from use of an intravenous contrast agent and repetition of the scanning in the lateral decubitus position. Eight diagnostically helpful radiologic findings were noted, some for the first time. (1) Radiodense retrolental soft tissue can be demonstrated along Cloquet's canal. (2) The retrolental tissue enhances after administration of intravenous iodine-containing contrast material. (3) Congenital nonattachment of the retina is demonstrable by CT. (4) There may be localized or generalized increased radiodensity of the vitreous body. However, some minimally affected cases have vitreous chambers with normal attenuation values, and CT evidence for PHPV may be lacking in such patients. (5) There may also be layered, high density fluid (blood) in the retrohyaloid space, which shifts location in the lateral decubitus position. Thus far, this finding appears to be unique to PHPV, but computed scanning of other neonatal ocular conditions will be necessary before concluding it is pathognomonic. (6) There is absence of ocular and intraorbital calcification. (7) Abnormalities in configuration of the eyeball, including microphthalmos, can be demonstrated. (8) Retrobulbar tissues and other orbital structures appear normal, and the optic nerves appear normal or minimally reduced in size.