[The posterior inferior cerebellar artery arising from the internal carotid artery directly: a variant of the persistent primitive hypoglossal artery].

We reported a rare case of the posterior inferior cerebellar artery arising from the internal carotid artery directly. A 33-year-old male was admitted to our hospital with the complaint of throbbing type headache. CT showed no abnormal findings. A saccular aneurysm at the bifurcation of the left middle cerebral artery was revealed by MR angiography and the left internal carotid angiography. The right internal carotid angiography demonstrated an anomalous branch originating at the level of the C1/2 in the cervical portion of the internal carotid artery. This branch terminated as the posterior inferior cerebellar artery without an interposed segment of the vertebro-basilar artery. The ipsilateral vertebral artery was aplasia. T2-weighted MR image showed a flow-void penetrating the right hypoglossal canal. This vessel was confirmed an artery passing through the hypoglossal canal with the source images of the three-dimensional time-of-flight MR angiography. We diagnosed it as a kind of variant of the persistent primitive hypoglossal artery. The persistent primitive hypoglossal artery is composed of the proximal segment derived from the primitive hypoglossal artery, and the distal segment consisting of portions of the lateral anastomotic channels (primitive lateral basillo-vertebral anastomosis) which give rise to the posterior inferior cerebellar artery. We speculated that this variant resulted from the persistence of the proximal segment, which communicated with the stem of the posterior inferior cerebellar artery via the distal segment, and next, the disconnection of the posterior inferior cerebellar artery origin with the vertebral artery due to the aplasia of right vertebral artery and the involution of the distal segment connected to the basilar artery.

Development of line-shaped optical system for green laser annealing used in the manufacture of low-temperature poly-Si thin-film transistors.

We have developed a new optical system that transforms the circle profile beam generated with near-Gaussian intensity distribution by a pulse green laser (YAG2omega laser; second harmonics of a Q-switched Nd:YAG laser) into a line-profile beam. For homogenization in the longitudinal direction, we employed a waveguide plate-type homogenizer. We successfully reduced interference fringes. In the width direction, the laser beam was focused up to the limited M2 value. This transformed beam has a uniform distribution to within 5% in the longitudinal direction, and it is approximately 100 mm long and 40 microm wide.