1902.] OLIVEE — BLINDNESS FROM MALFORMATION OF SKULL. 169 



unstable increases of intracranial pressure from ventricular disturb- 

 ances are frequent, giving rise to repeated optic nerve-head swell- 

 ings and retinal extravasations. 



The head of the leptocephalic type is small. This condition is 

 caused by a too early union of the fronto-sphenoidal suture between 

 the alae of the frontal and sphenoidal bones. In this type the in- 

 tracranial distortions, particularly thofe that affect the foramina and 

 fissures between the body and the greater and lesser wings of the 

 sphenoid bone, bring optic nerve atrophy from previous inflamma- 

 tion, and later palsies of the exterior ocular muscles, into existence 

 very soon after birth. < 



The trigonocephalic or three-cornered type of cranial deformity, 

 with its small end situated anteriorly, is dependent upon a prema- 

 ture or improper ossification of the frontal and parietal bones along 

 the coronal suture, particularly in the region of the bregma or 

 pterion ; or, at times, it may be due to a fault in osseous ankylosis 

 of the combined frontal bones along the metoptic suture-line. 

 Postneuritic atrophy, the principal ocular expression of the disease, 

 occurring quite early in postnatal life, is apt to appear in the gross 

 examples of the type. 



The rarely seen occipital or occipito-parietal type of cranial 

 deformity exhibits a flattened curving of the posterior portion of 

 the cranium. The condition seems to be dependent upon either a 

 too early syntosis of the occipital suture, especially at the lambdal 

 region, or an improper union of the medial portion of the lamb- 

 doidal and postero-inferior part of the sagittal suture in the region 

 of the posterior fontanelle. Here, in the superior and the posterior 

 parts of the deepest portion of the intracranial cavity (in the 

 interparietal parts of the occipital bone above the grooves for the 

 lateral sinus), the osseous tissues are distorted and flattened. In 

 certain places this condition is so pronounced, that in some situa- 

 tions the cerebral fossa are almost annihilated, and the inmost por- 

 tion of the elevation of the superior longitudinal sinus and falx 

 cerebri is increased. The most marked ocular signs are almost 

 wholly sensory in character. Vision in each eye is nearly or entirely 

 lost. The orbits are shallow, particularly at their postero-mesial 

 parts. The eyeballs are but slightly proptosed, somewhat enlarged, 

 and enjoy full freedom of movement. The motor apparatus of the 

 exterior of the eyes, with the exception of a few minor discrepan- 

 cies of probable improper nuclear action, is in good working 



