A previously undescribed variant of the confluence of sinuses

Circular configuration of Torcular Herophili presenting as childhood headache

“…In both cases, headache was the presentation presumably due to raised intracranial pressure and had an unilateral absent transverse sinus. Tardieu et al have proposed that circular con guration of the torcular herophili along with unilateral absence of transverse sinus may impair venous drainage causing cerebral oedema explaining the clinical symptom of the patient [2]. We propose that the association of circular torcular herophili with unilateral absent transverse sinus predisposes the patients to episodes of raised intracranial pressure and should be closely observed.…”

“…Several anatomical variations of the torcular herophili have been noted and Kobayashi et al classi ed variants of the torcular herophili into nine types with type 1 being the most common [1]. Tardieu et al reported a previously unreported variant of the torcular herophili with a circular con guration along with absent right transverse sinus [2]. A second case was reported by Lake et al in a cadaveric case [3] 3 .…”

A Cadaveric Case of a Circular Torcular Herophili

“…They reported that venous flow from the superior sagittal sinus to the transverse sinus could be either symmetric or asymmetric [ 5 ]. The findings of the Matsuda et al study added to the literature compilation that established venous drainage at the torcular as symmetric or asymmetric [ 1 - 2 , 4 , 6 - 7 ]. Despite the asymmetry of venous flow, on venography, the torcular usually forms an inverted T shape—with the superior sagittal sinus representing free communication between the superior sagittal, the straight, the occipital, and the transverse sinuses [ 6 ].…”

“…Recently, a circular variant of the torcular was reported on magnetic resonance imaging from a patient suffering from chronic headaches and questionable papilledema [ 4 ]. In the present case, a similar finding was seen in a cadaveric dissection.…”

“…The classical form of the torcular represents the most common subtype [ 2 - 3 ]. Other subtypes are under-reported throughout the literature and can have clinical/surgical implications [ 4 ].…”