Abstract: Objective    To investigate the incidence and imaging anatomical features of intracranial falcine sinus in healthy human.   Methods    The data of three-dimensional enhanced magnetic resonance angiography (3D CE-MRV) of 177 healthy patients (81 males and 96 females) with complete falcine and dural venous sinus were analyzed, and volume rendering technique (VRT) was used to observe the falcine sinus. Results     The falcine sinus was found in the cerebral falx of 43 patients, of which 37 patients were located at the junction of the middle and posterior one third region of the cerebral falx. Six patients were located at the posterior one third region of the cerebral falx. According to the structure of the veins connecting to the two ends, the falcine sinus was divided into three types: type Ⅰ (derived from the cerebral falx, injected into the inferior sagittal sinus, vein of Galen or straight sinus), type Ⅱ (derived from the cerebral falx and injected into the posterior part of the superior sagittal sinus) and type Ⅲ (connected the superior sagittal sinus to the inferior sagittal sinus、vein of Galen or straight sinus). Type I falcine sinus consisted of mass-type, triangle-type, strip-type and irregular shape-type. Type II falcine sinus included straight strip-type and curved strip-type. Type III falcine sinus included thin strip-type, wide band-type and V-type. The V-type was usually formed by the fusion of type I and type II falcine sinuses. A total of 11 cases of type Ⅰ falcine sinus, 21 cases of type Ⅱ falcine sinus and 14 cases of type Ⅲ falcine sinus were found (figure 1). Among them, 4 patients had type Ⅰ falcine sinus and type Ⅱ falcine sinus simultaneously, 6 patients had type Ⅱ falcine sinus and type Ⅲ falcine sinus simultaneously, 5 patients had double type Ⅱ falcine sinus, and 4 patients had triple type Ⅱ falcine sinus in their cerebral falx.   Conclusions   3D CE-MRV combined with VRT is a good method for observing falcine sinus. Falcine sinus is not rare and has various types.

Key words: Cerebral falx,  ,  , Falcine sinus,  ,  , Magnetic resonance venography,  ,  , Volume rendering technique