Introduction: Variety of tumors could involve the skull; however, very few may occur over the midline. Some may affect venous blood flow of superior sagittal sinus. Few challenging cases are presented Material: 1-Rare case of osteoblastoma over the torcula, (headache, visual symptoms, papilledema, VI nerve palsy). 2- Rare case of metastatic liposarcoma involving midsagital sinus, partially occluding it (headache and visual blurring). 3- A huge atypical (grade2) meningioma over the vertex Method: Case #1, the tumor over the venous confluences (torcula) was removed easily, without any complications. Complete resolution of symptoms Case #2, complete en-block resection of tumor, with sacrifice of mid-sagittal portion of sinus, without any neurological sequellae. Case #3, subtotal resection, followed by radiotherapy.
Discussion &Conclusion: Anterior 3rd of sagital sinus could be sacrificed (if necessary), without major consequences. However, whenever mid or posterior portion of the sinus is involved, interruption of venous flow could pose very serious complications. Occasionally, chronic compression of sinus may force increasing collateral venous return, in which case one may attempt a complete resection of the lesion, with sacrifice of part of the sinus, as in our second case. In the region of torcula, however, one should be very careful not to damage it