Jefferson Browder

Variations of the cerebral dural sinuses at the torcular herophili: Importance in radical neck dissection☆

Abstract The cerebral dural sinuses of 215 specimens of dura obtained at autopsy were studied and diagrammed. Particular attention was accorded the anatomic arrangement of the major sinuses that converge to form the torcular. In 57 per cent of the specimens there was free communication between the superior sagittal, the straight, the occipital, and the transverse sinuses at the torcular. In 43 per cent there was maldevelopment of one or more of these major sinuses at or near the torcular. Consideration is given to the clinical import of these variations subsequent to ablation of a part or all of the jugular venous system in the neck.

Venous Channels within the Intracranial Dural Partitions

Complete dura maters exclusive of their midline basilar attachments were obtained by autopsy from persons of all age groups. Vinylite casts of the venous channels in the diaphragma sellae, falx cerebelli, falx cerebri, and tentorium cerebelli were made by injecting a mixture of Vinylite and acetone, after which the specimens were fixed in formalin and subsequently corroded with concentrated hydrochloric acid. Studies showed that the size and position of the channels within the diaphragma sellae were quite constant. Large venous lakes were present in the falx cerebelli and contiguous suboccipital dura mater, and venous pools were also seen connecting the caudal end of the inferior sagittal sinus and the superior sagittal sinus. A great variety of channels were observed in the tentorium cerebelli.

Narrow and Atretic Transverse Dural Sinuses: Clinical Significance

In 422 specimens of cerebral dural sinuses obtained at autopsy, there were 13 with marked narrowing of a segment of one or the other transverse sinuses, and 11 with absence of a part or all of a transverse sinus. In both groups a variety of compensatory venous channels had formed during embryonal development, apparently serving as bypasses for the partially or completely occluded transverse sinus. A knowledge of the anatomical variances at the confluence of sinuses is important to surgeons who manage patients with inflammatory problems implicating a transverse sinus and those performing radical dissection of the neck for cancer.

Atresia of the rostral superior sagittal sinus: Associated cerebral venous patterns

SummaryIt has been accepted generally that the supperior sagittal sinus takes origin at the foramen caecum. While this obtains in a few, 58 per cent of the cadaver specimens examined have a one-to-three centimeter atresia of the most rostral end of the sinus. In these the veins of the frontal poles of the brain were directed medially and caudally to join in the midline, thus establishing the lumen of the sinus. In instances of more extensive atresia, the anterior superior cerebral veins, as well as those from the infero-mesial poles, all course medially and caudally to form the sinus. In other words, the longer the atretic segment, the more striking the change in venous patterns of the superior and mesial frontal lobes of the brain.RésuméOn admet généralement que le sinus sagittal supérieur naît dans le foramen caecum. Mais 58% des cadavres examinés présentaient une atrésie de 1à 3 cm de l’extrémité la plus rostrale du sinus. Dans ces cas, les veines des pôles frontaux du cerveau se dirigeaient vers le milieu et le bas pour se joindre sur la ligne médiane, formant le lument du sinus. En cas d’atrésie plus étendue, les veines cérébrales antéro-supérieures et les veines des pôles inféro-médians sont médianes et se dirigent vers l’arrière pour former le sinus. En d’autres termes, plus l’atrésie est étendue, plus les modifications des veines sont importantes sur les parties supérieures et médio-frontales du cerveau.ZusammenfassungBei einer Atresie des rostralen Sinus-Abschnitts die mehr oder weniger ausgeprägt sein kann, kommt es zu einer bestimmten Veränderung des venösen Abflusses im Bereich der Frontallappen.