頸動脈造影による正常脳血管像の計測的研究—ＩＩ．静脈像

TOPOMETRIC STUDY OF THE NORMAL CAROTID ANGIOGRAMS: II. PHLEBOGRAMS

Ｉ．はじめに

　一般に表在性脳静脈の走行は個体による正常変異がきわめて大であるが，深部脳静脈系の走行および形態は変異が少なく定常的である。

　また脳血管は他の身体部位とは異なり動脈と静脈が随伴せず，大脳深部の正中部や傍正中部では深部静脈系のみがよく造影されるため，これらの部位の空間占有性病変では動脈系にあまり影響を与えず，深部脳静脈系のみに変化を与えることがある。そのために頭蓋内空間占有性病変，特に深部病変の局在診断における深部脳静脈系に関する研究が古くから行なわれてきた^1）〜22）。

Topometric study of the normal cerebral phle-bograms was made, using about 120 normal phle-bograms with good filling of the deep cerebral veins which came from only the patients over the ages of twenty. All of these cerebral phlebograms used in this study were interpreted as being normal, since the history, neurologic and ophthalmological exa-mination, C. S. F. study, electroencephalographic examination and subsequent follow up have failed to reveal any intracranial organic lesions.

The angiographic measurements of the position and the configuration of the venous angle, the in-ternal cerebral vein, the cerebral basal vein and the great vein of Galen were statistically analysed in both the lateral and the antero-posterior view, to establish the normal limits of the position and the configuration of the deep cerebral veins.

The cranial landmarks and basic lines used for measurement were illustrated in Figure 1 in the lateral and in Figure 2 in antero-posterior view.

Lateral view ; The two basic lines were drawn, one the line endobregma-basion, the other the line endolambdo-junction point of the anterior leg of the basal angle with inner table of the skull.

The venous angle lie within a circle 3. 9 mm in diameter which has center in cross point of the two basic lines.

The distances from the parietal inner table of the skull to the venous angle, to the midpoint of the internal cerebral vein and to the most proximal point of the great vein of Galen are 46. 4 ±2%, 45. 5±2. 3% and 54. 5±1. 7% of the distance of the supero-inferior line of the skull respectively.

The distances from the parietal inner table of the skull to the most anterior point of the basal vein and to the midpoint of the basal vein are 62. 8 ± 2. 5% and 62. 1 ± 2. 2% of the distance of the supero-inferior line of the skull.

The distance from the internal cerebral vein to the basal vein is 24. 3±3. 0 mm at its most anterior portion and at the midpoint.

Antero-posterior view ;

The distance from the tip of the thalamostriate vein to the midline of the skull is 27. 2±2. 4% of the horizontal distance from the midline to the outer surface of the skull.

The venous angle is normaly situated at a distance of 1 mm from the midline.

The distance from the midline to the most lateral point and to the most medial point of the basal vein are 30. 7±2. 5% and 18. 8±2. 4% respectively.

The deep cerebral venous system was less var-able than the other cerebral vessels in its position iand configuration. It could be statistically proved that there were intimate correlation between the shape of the skull and the position and the con-figuration of the median and paramedian running vessels.