A cerebrospinal fluid flow diverter, comprising: a cover level having a cover top side and a cover underside, the cover level comprising a cap-like structure having a plurality of securing holes (210D, 220D, 230D) from the cover top side through the cover underside; a membrane level, the membrane level comprising a plurality of membrane level securing members, a flexible membrane, a tapered side portion, and a chamber, wherein the flexible membrane forms the bottom boundary of the chamber and covers it; a retaining level, comprising a ring-like structure having a substantially circular retaining member with a hollow center; a plurality of skull-securing mechanism passing through the plurality of securing holes and into the skull of the patient; a nib passing through the cover top side, through the cover underside and opening into the chamber; wherein the membrane level is attached to the cover underside by securing the plurality of membrane level securing members between the substantially circular retaining member and the cover underside so that the flexible membrane, the tapered side portion, and the chamber pass through the hollow center of the substantially circular retaining member and the top of the chamber is covered by the cover underside; wherein the chamber is filled with compressible matter; wherein after the tapered side portion and the flexible membrane are inserted in a skull of a patient, the volume of the chamber is selectively increased and decreased in volume by the ongoing displacement of the flexible membrane during a cardiac cycle in the patient, thereby modulating the cerebrospinal flow in the patient. a cover level having a cover top side and a cover underside, the cover level comprising a cap-like structure having a plurality of securing holes (210D, 220D, 230D) from the cover top side through the cover underside; a membrane level, the membrane level comprising a plurality of membrane level securing members, a flexible membrane, a tapered side portion, and a chamber, wherein the flexible membrane forms the bottom boundary of the chamber and covers it; a retaining level, comprising a ring-like structure having a substantially circular retaining member with a hollow center; a plurality of skull-securing mechanism passing through the plurality of securing holes and into the skull of the patient; a nib passing through the cover top side, through the cover underside and opening into the chamber; wherein the membrane level is attached to the cover underside by securing the plurality of membrane level securing members between the substantially circular retaining member and the cover underside so that the flexible membrane, the tapered side portion, and the chamber pass through the hollow center of the substantially circular retaining member and the top of the chamber is covered by the cover underside; wherein the chamber is filled with compressible matter; wherein after the tapered side portion and the flexible membrane are inserted in a skull of a patient, the volume of the chamber is selectively increased and decreased in volume by the ongoing displacement of the flexible membrane during a cardiac cycle in the patient, thereby modulating the cerebrospinal flow in the patient.