chronic subdural hematoma ( csdh ) is an amount of liquid blood with dark red color surrounded by a thin capsule which usually formed for approximately 3 weeks . the old age increases greatly the incidence of csdh , which amounts to 8 - 58 per 100.000 residents over the age 65 . according to virchow chronic inflammation of the meninges , head trauma is usually considered responsible for the development of csdh , especially in older people , which initially seems insignificant , may be the cause for the genesis of csdh . most of patients with csdh , which is manifested with clinical symptoms , should be operated for evacuation of csdh . the surgical intervention can be performed with a range of procedures starting from twist drill craniostomy to craniotomy and membranectomy . burr - hole craniostomy is an easier and more efficient surgical procedure , which is usually selected for drainage of uncomplicated csdh . evacuation of csdh through burr - hole becomes the procedure of choice in many hospitals because of its simplicity and the lower operative risks . however , it has been reported that recurrence rate range from 9.2% to 26.5% after application of this procedure for surgical evacuation . however , there are some studies that have been reported of other recurrence values , which were from 2.3% to 37% . have mentioned some studies about numerous factors potentially associated with recurrences after the surgical procedures which are still highly controversial . the present retrospective study analyzed the results a single one versus two burr - hole trepanation with closed - system drainage or craniotomy . this is a retrospective study that included 137 patients with csdh treated in clinic of neurosurgery , university clinical center of kosova during the period 20082012 . the data were collected and analyzed from the archives and protocols of the university clinical center of kosova . diagnosis was confirmed by computed tomography ( ct ) scans and/or by magnetic resonance ( mr ) images in all patients . a surgical evacuation was performed when the hematoma 's thickness was larger than 10 mm , when focal symptoms were present , or when there were significant changes in neurologic status in patients with csdh of any thickness . in patients who have used oral anticoagulants , this therapy has been stopped until normalization of international normalized ratio ( inr ) . in case of an emergency procedure and coagulopathy , anticoagulant status was reversed with vitamin k and fresh frozen plasma , in order to immediately perform surgery procedure . in order to prevent infections preoperatively , we used antibiotics of third generation cephalosporin . we used different surgical procedures such as one or two burr - hole trepanation with closed - system drainage or craniotomy with membranectomy . the selection of the number of burr - holes was dependent on the neurosurgeon 's preference . the burr - hole trepanation was made at the site of the maximal existing hematoma . after the dura has been opened , the collection of blood was evacuated under its own tension , and irrigation was performed using physiological saline solution until clear fluid came out . thereafter , a closed subdural system has been placed , which works without any negative pressure , ( infant feeding tube was used instead of subdural catheter ) . after evacuation of the hematoma , the patients routinely received intravenous fluid therapy consisted of crystalloids approximately 2000 ml / day over at least 3 postoperative days . subcutaneous injection of 40 mg of enoxaparin was used after 24 h of surgical procedures for prophylaxis against deep vein thrombosis during the patient 's hospitalization . the patients were analyzed by age , sex , the presenting signs and symptoms , glasgow coma scale ( gcs ) , origin type of surgical procedure , side of the skull in which the hematoma occurred , days of hospitalization , glasgow outcome scale ( gos ) at discharge , recurrence and mortality . data testing is done with t - test and the difference is significant if p < 0.05 . in this retrospective study are included 137 patients in a 5 year period with csdh treated in clinic of neurosurgery , university clinical center of kosova . out of 137 patients , csdh was predominant in male gender with 106 cases or 77.3% , while 31 cases were female or 22.7% , and male to female ratio was 3.4:1 . patients with csdh had a very wide age distribution from 1 to 89 years with an average age of 62.85 years . regarding the age group , the age group 70 - 79 with 44 cases dominates , followed by the age group 60 - 69 years 30 cases , 80 - 89 years 22 cases , 40 - 49 years 11 cases , 10 - 19 years 5 cases , 01 - 09 years 4 cases , 20 - 29 years 2 cases , and 30 - 39 years 2 cases [ table 1 ] . clinical presentation of patients with csdh was characterized with a lot of symptoms [ table 2 ] , from which the headache was a common symptom , occurring in 92 patients ( 67.1% ) , which was followed by contralateral motor deficit 66 patients ( 48.1% ) , speech disturbance 37 patients ( 27% ) , and altered behavior 34 patients ( 24.8% ) . head trauma was the most frequent cause , which has been responsible for csdh in 88 patients or 64.2% while 49 patients ( 35.7% ) did not have definite history of head trauma [ table 3 ] . as shown in this table there are other presented factors associated with csdh such as : concomitant systemic disease was identified in 45 patients ( 32.8% ) , arterial hypertension in 35 patients ( 25.5% ) , cardiopathy in 17 ( 12.4% ) , psycho - organic syndrome in 13 ( 9.4% ) , diabetes 20 ( 14.5% ) , obstructive chronic bronchopathy in 3 ( 2.1% ) , chronic renal failure in 2 cases ( 1.4% ) , after v - p shunt in 2 cases ( 1.4% ) , hematological disease in 2 cases ( 1.4% ) , chronic alcoholism in 3 cases ( 2.1% ) , anticoagulant drug use in 8 ( 5.8% ) and antiaggregant drug use in 17 ( 12.4% ) . in table 2 , patients are presented based on gcs at admission as follows : 91 patients ( 66.4% ) had gcs of 15 - 14 points , 31 patients ( 22.6% ) had gcs of 13 - 9 points and 15 patients ( 10.9% ) had gcs of 8 - 3 points ( table per gcs ) . general characteristics of patients with csdh clinical presentation of patients with csdh factors associated with development of csdh in our series out of the total number of patients ( 137 ) , 119 or 86.8% of them had positive outcome ( gos 5 ) , while 14 patients or 10.2% ( gos 4 - 2 ) had poor outcome . the general outcome at the time of discharge were assessed according to gos with range 1 - 5 . in 105 ( 76.6% ) patients , diagnosis of csdh was confirmed with computed tomography ( ct ) , while in 32 ( 23.4% ) patients with magnetic resonance imaging ( mri ) . the majority of patients ( 92 or 67.1% ) were operated under local anesthesia ( monitored anesthesia care ) , while the remaining ( 45 or 32.8% ) under general anesthesia [ table 4 ] . localization of hematomas , diagnosis , type of anesthesia and applied surgical procedure hematoma localization has been greater on the left side ( 62 patients or 45.2% ) than on the right side ( 54 patients or 39.4% ) , while bilateral hematomas were present in 21 patients or 15.3% . our patients were treated with one versus two burr - hole trepanation , but some of them by craniotomy . forty - seven patients with the hematoma of the left side were treated with a one burr - hole trepanation , whereas 10 of them were treated with two burr - hole trepanation , and 5 of them with craniotomy . the treatment of hematoma on the right side is made similar to that on the left side : 36 with one burr - hole trepanation , 14 with two burr - hole trepanation and 4 with craniotomy . of 21 patients with bilateral hematoma , 18 of them are treated with one burr - hole trepanation per side , in 2 cases are made two burr - hole trepanation per side and only 1 patient was treated with bilateral craniotomy [ table 4 ] . the duration of hospitalization ranged from 2 to 46 days , with a mean of 8.6 days of hospitalization . duration of treatment in 26 cases ( 18.9% ) was over 10 days , with the maximum days of hospitalization up to 46 days , whereas in 23 cases ( 16.7% ) it was up to 5 days . in 88 cases ( 64.2% ) , hospitalization lasted up to 10 days . reviewed by the years that have been analyzed , it is seen that distribution of csdh had the following features : in 2012 the incidence of csdh was the highest ( 35 cases or 25.5% ) , while in 2010 it was the lowest ( 21 cases or 15.3% ) . distribution of csdh in years had the following features : 2012 is the year in which the incidence of csdh was the highest with 35 cases ( 25.5% ) , followed by 2009 with 28 cases ( 20.4% ) , 2011 with 27 cases ( 19.8% ) , 2008 with 26 cases ( 18.9% ) , and 2010 with 21 cases ( 15.4% ) . among 137 operated patients , 9 patients ( 6.5% ) we did not register any case of further recurrence ( re - recurrence ) , as well as for other complication such as : postoperative subdural empyema , meningitis and wound infection . it is worth - mentioning that of the total number of operated patients , four of them ( 2.9% ) died in the early post - operative period . csdh is relatively common in neurosurgical practice , which is caused by a large number of etiological factors , first of all by the action of various traumatic factors . however , the etiology of csdh is not completely understood until now . the purpose of this retrospective paper was to present the cases with csdh which were surgically treated in our clinic ( 137 patient ) during the period of 5 years , from 2008 to 2012 . patients who were treated in our clinic were analyzed in many aspects such as age , gender , etiological factors , clinical features , localization , diagnosis , methods of surgical interventions of csdh , gcs and gos , distribution of csdh over years , concomitant diseases , duration of hospitalization , recurrences and mortality of patients . according to the data from literature , csdh is pathologic condition which is mostly present in older people from 50 to 70 years . the average age of our patients ( 62.85 years ) was younger than the average age reported by other authors such as gelabert - gonzales et al . the ratio of male to female which we found in our patients ( 3.4:1 ) was higher than ratio which is found by above authors , which was 1.68:1 . also , the higher frequency of csdh in males compared to females was found by other authors . as reported in our results , head trauma was the most frequent cause responsible for csdh in 88 patients or 64.2% , while 49 patients ( 35.7% ) did not have definite history of head trauma , but may be due to some other pathological conditions such as : arterial hypertension , hematological disease , chronic renal failure , after v - p shunt , chronic alcoholism , patients under anticoagulant and antiaggregant therapy . our results about the frequency of head trauma ( 64.2% ) as a causative factor for csdh are similar to those of other authors , which report that head trauma is responsible for csdh in 35 - 75% of patients . the dominant symptom was headache ( 67.1% ) , whereas seizure was present in only 3.6% of cases [ table 2 ] . the similarly symptoms and the same frequency were reported also by gelabert - gonzlez et al . , mori and maeda , and sousa et al . our results are in accordance with the results of sousa et al . about the finding that headache is more frequent in younger patients . we have found that the csdh is more frequent on the left side ( 45.3% ) , compared with the right side ( 39.4% ) , while bilateral csdh have been in lowest percentage ( 15.3% ) . also , other authors have reported the higher frequency of the csdh on the left side . surgical procedures for patients with csdh were performed with one versus two burr - hole trepanation with a closed drainage system and craniotomy . some authors agree that the optimal surgical treatment of patients with csdh can be achieved with one burr - hole trepanation with a closed drainage system . we have used this surgical procedure in our clinic in 101 patients or in 73.7% of them . although the opinion of the other authors is different , they think that extended craniotomy enables better exposure of csdh with solid components . the data from literature show that regardless of surgical procedures , the operation is accompanied by recurrence rates of 4% to 26% . the number of recurrence in our series was 6.5% equals those of the other authors . according to the robinson , old age considered to be a risk factor for recurrence . our results are in accordance with this conclusion , because the average age ( 71.44 years ) of our 9 re - operated patients has been higher than the average age ( 62.25 years ) of non - re - operated patients . in the present study , recurrence of csdh was found at 1 to 12 weeks ( mean 4.5 weeks ) after the first operation . however , in some studies , it is not demonstrated the relationship between recurrence rate and age . furthermore , acquired or inherited disorders of homeostasis represent a very important clinical factor , which are responsible for the csdh and consequently for recurrence and mortality rate . in the present study , we have found five cases with iatrogenic csdh , who have been under uncontrolled treatment with oral anticoagulants ( four cases ) and antiaggregants ( one case ) . four patients ( 2.9% ) of our series have died in the early post - operative period , in comparison to 2.7% mortality reported in the literature . however , according to some authors , mortality varies from 0% to 13% . one of the most frequent neurosurgical problems is the csdh , which unfortunately can lead to the death of the patients . for this reason , there are a lot of retrospective studies , which describe the basic characteristics of the csdh such as : the incidence , etiology and pathogenesis , clinical symptoms , diagnostic and surgical procedures , success of treatment , recurrence and mortality . in the present study , the most common etiological factor was the head trauma , whereas the headache was the most frequent symptom in younger patients . diagnosis and localization of the csdh were done with ct or mri , while in the majority of the patients , the operative treatment was performed with burr - hole trepanation with closed drainage system , which according to some authors is a simple , safe and efficient method . we expect even better results if we use subdural catheter instead of infant feeding tub . however , the kind of surgical method is still controversial , and a standard method does not exist . in our experience , there are several factors ( concomitant disease , diabetes , arterial hypertension , etc . ) , which act negatively on operating outcome . despite any cases of perioperative deaths
background : chronic subdural hematoma ( csdh ) is frequent pathology in neurosurgical practice . 
 the aim of this study is to present the first series of patients with csdh , who got surgically treated in clinic of neurosurgery , university clinical center of kosovo.materials and methods : this is a retrospective study that included 137 patients with csdh who had been treated during the period 20082012 . 
 the data were collected and analyzed from the archives and protocols of the university clinical center of kosovo . 
 patients were analyzed in many aspects such as age , gender , etiological factors , clinical features , localization , diagnoses , methods of surgical interventions , recurrences and mortality of patients.results:from 137 patients with csdh , 106 ( 77.3% ) were males and 31 ( 22.7% ) females . 
 average age of patients was 62.85 years . analyzed according to the decades , the highest number of causes with csdh was between 70 and 79 years ( 46% ) . 
 the head trauma has been responsible for csdh in 88 patients ( 64.3% ) , while the main symptom was headache ( 92 patients or 67.1% ) . 
 one burr - hole trepanation with closed drainage system has been used in majority of cases ( in 101 patients or 73.7% ) . 
 the recurrence of csdh was 6.5% , whereas mortality 2.9%.conclusion : csdh is more common in elderly patients . 
 the male - female ratio is 3.4:1 . 
 like other authors we also think that treatment with one burr - hole and drainage is a method of choice , because of its simplicity and safety .