A fluid interface device for delivering fluid to and/or withdrawing fluid from a patient, the device comprises a peripheral base element (2) and a fluid transmission element (4) sealingly connected to the base element and forming a central portion of the device. The fluid transmission element comprises a front platelet (6) with a primary face (8) and a secondary face (10) opposed thereto, the primary face being in contact with a patient's body fluid region (12) when the device is implanted in the patient, the fluid transmission element further comprising a counterplate (14) sealingly stacked against the secondary face of the front platelet and forming a buffer volume (16) therebetween. The front platelet comprises at least one array of microchannels (18) defining a fluid passage between the buffer volume and the primary face, the microchannels having an opening of 0.2 to 10μηι. The counterplate has at least one fluid port (20； 20a, 20b) for fluid delivery to and/or fluid withdrawal from the buffer volume.
