The present invention relates to a medical device, in particular blood cassette (200), having a device body (201) and having at least one fluid reception chamber (1) for receiving at least one first medical fluid (5), in particular blood and having at least one hydrophobic filter device with a filter surface through which the fluid reception chamber (1) is supplied with at least a second gaseous fluid (19), in particular air, wherein the filter device comprises at least one filter membrane (9) wherein the filter membrane has a rear side (9a) and a front side (9b) wherein the filter membrane (9) is welded to the fluid reception chamber (1), to a wall thereof or to another section of the cassette body (201) along a weld section (203) wherein the filter device comprises a front support structure (27) on or at front side (9b), which is arranged for supporting the filter membrane (9) wherein the front support structure (27) is arranged to contact the weld seam section (203) by means of a first contact section (27a) of the front support structure (27).本發明有關一種醫療裝置,尤其有關一種血液盒(200)。此種醫療裝置具有一裝置本體(201)及具有至少一個流體容置室(1)用以容置至少一第一醫療流體(5),尤其是血液;以及具有至少一疏水性過濾裝置,其具有一過濾表面,經由該過濾表面,至少一第二氣態流體(19),尤其是空氣,可而供應至該流體容置室(1);其中,該過濾裝置包括至少一濾膜(9);其中,該濾膜(9)具有一後側(9a)及一前側(9b);其中,該濾膜(9)係沿一熔接區段(203)熔接至該流體容置室(1)、至其一壁部或熔接至該裝置本體(201)之另一區段;其中,該過濾裝置在該前側(9b)或該前側(9b)之上包括一前支撐結構(27)用以支撐該濾膜(9);其中,該前支撐結構(27)係經由其一第一接觸部(27a)而接觸該熔接縫區段(203)。9‧‧‧濾膜11‧‧‧後支撐結構11a‧‧‧突節或突出部27a‧‧‧前支撐結構之第一接觸部27b‧‧‧突節或突出部203‧‧‧熔接區段203a‧‧‧熔接縫203b‧‧‧區段I‧‧‧方向I
