ObjectiveThe population suffering from chronic/subacute subdural hematomas (SDHs) generally includes elderly patients with co-morbidities; therefore the success of less invasive surgical techniques has been of long standing interest. The optimum treatment option for chronic/subacute SDH has not been well established. We report our retrospective outcomes of SDH drainage through a subdural evacuating port system (SEPS). Patients and methodsFifty-two consecutive adult patients with chronic/subacute SDH treated with SEPS (total 64 procedures), over a period of 3years (June 2006–June 2009), were included. 9/52 patients had SEPS performed for bilateral SDHs. Three patients had SEPS placed for recurrent SDH. This retrospective study was approved by the Institutional Review Board of SUNY Upstate Medical University and Crouse Hospital. ResultsOverall 38/52 patients (73%) showed clinical improvement, 10/52 patients (19%) did not show any clinical improvement and 4/52 (8%) patients became clinically worse after the SEPS placement during initial hospitalization. 41/52 patients, treated initially with SEPS were followed as outpatients. 32/41 patients improved, returning to baseline neurological status, 5/41 patients improved, but still had some residual symptoms. The remaining 4/41 patients, presented with recurrent symptoms and had recurrent SDH on CT scans. During the in-hospital post-SEPS period, 8 SDH had >75% decrease, 17 SDH had between 50 and 75% decrease, 23 SDH had between 25 and 50% decrease and 14 procedures had <25% decrease in maximal width of the SDH on postoperative scans. Outpatient follow up CT scans after SEPS placement were available for 46/64 procedures. At final outpatient follow up, 33/46 SDHs showed >75% decrease in maximal thickness, 4/46 SDH showed between 50 and 75% and 2/46 SDH showed between 25 and 50% decreases in maximal width of chronic SDH. However, in 7/46 patients, SDH re-accumulated (i.e. increased in thickness) as outpatients, after initial response to treatment on post-operative in-hospital CT scans. ConclusionSEPS is an effective, relatively safe and convenient treatment strategy with low invasiveness; among management options of chronic/subacute SDH.