Is the Size of an Epidural Haematoma Related to Outcome?

Summary  Recently we treated 54 patients with acute epidural haematoma, diagnosed by early CT scan and operated on quickly, within 6 hours after trauma.  In 18 cases the volume of the haematoma, calculated by three different methods, was more than 150 cc, and GCS score was equal to or less than 8.  In all 18 patients, as well as in another 36, we obtained good results: all patients survived and 17 fully recovered (only one was left with moderate neurological disability).  Our experience leads us to the conclusion that even volumes of over 150 cc can be compatible not only with survival but also with very low morbidity, if rapid surgical treatment is performed.     

The Application of Transcranial Doppler Sonography in Patients with Chronic Subdural Haematoma

Summary  The aim of this study was to evaluate the haemodynamic changes of the middle cerebral artery (MCA) and their clinical significance before and after surgical aspiration in patients with chronic subdural haematoma (CSDH).  Nineteen patients with CSDH (17 unilateral and 2 bilateral) received transcranial Doppler sonography (TCD) examinations for cerebral blood flow velocity (CBFv) of the MCA prior to and 5 days after neurosurgical treatment. A total of 21 lesion and 10 non-lesion hemispheres were included. Cranial computerized tomography (CT) and clinical assessments were performed before and 3 months following surgery.  The preoperative TCD study revealed that the lesion hemisphere had a modest decrease in CBFv in the MCA as compared to the non-lesion hemisphere. Postoperatively, the CBFv significantly improved in the lesion hemisphere, but not in the non-lesion hemisphere, compared to the preoperative data (P<0.005). The improvement in CBFv showed no significant correlation with brain shift and haematoma volume of the initial cranial CT. Additionally, two patients, who were proved to have a postoperative complication of subdural pneumocephalus, failed to attend follow-up examinations of TCD.  Our results support TCD as an alternative follow-up examination for patients with CSDH, although it may not be sensitive enough as a preoperative screening tool. Postoperatively, improvements in the CBFv of the lesion hemisphere are characteristic. An unexplained difficulty of accessing cerebral basal arteries in follow-up TCD examinations should suggest pneumocephalus in the primary differential diagnosis.     

Spontaneous Chronic and Subacute Subdural Haematoma in Young Adults

Summary  Spontaneous subacute and chronic haematoma in young adults is rare. It has not been previously reported in this age group.  We present three cases of chronic and subacute subdural haematoma in young adults, in one of whom the diagnosis was certainly delayed.  All three patients underwent burrhole evacuation and made a full neurological recovery. A cause for the haematoma was never established. The literature on the subject, which is scanty, is reviewed and the condition is briefly discussed. The aetiology remains obscure.     

Spontaneous bilateral chronic subdural haematoma of the posterior fossa. Case report and review of the literature

Summary. Summary.   Introduction: Chronic subdural haematomas of the posterior fossa in adults without a history of trauma are very rare. To our knowledge, only 15 cases have so far been reported in the literature, including those with anticoagulation therapy. A case of spontaneous bilateral infratentorial chronic subdural haematoma associated with anticoagulation therapy in an alive adult is presented and the relevant literature is reviewed.   Case Report: A 70 year old female presented with progressive dizziness, vertigo and gait ataxia. She was on anticoagulation therapy for heart disease. Neuro-imaging revealed bilateral infratentorial subdural masses.  The subdural masses were suspects for chronic subdural haematomas by neuroradiological criteria. Because of the progressive symptomatology, the haematomas were emptied through burrhole trepanations. Chocolate-colored fluid, not containing clotted components, gushed out under great pressure. The source of bleeding could not be identified. The patient recovered well from surgery, but died 4 months later shortly after admission to another hospital from heart failure.   Discussion: The chronic subdural haematomas in this patient may have been due to rupture of bridging veins caused by a very mild trauma not noticed by the patient and possibly aggravated by the anticoagulation therapy. Infratentorial chronic subdural haematoma should at least be a part of the differential diagnosis in elderly patients with cerebellar and vestibular symptomatology even without a history of trauma.     

Coagulopathy Induced Spinal Intradural Extramedullary Haematoma: Report of Three Cases and Review of the Literature

Summary  In a retrospective review of 3 patients operated for coagulopathy induced spinal intradural-extramedullary haematoma the literature regarding coagulopathy induced spinal haemorrhage is reviewed and the etiology of these rare spinal subdural and subarachnoid haemorrhages is discussed.  Spinal intradural haematomas are usually related to trauma or a previous lumbar puncture. A review of the literature revealed only a handful cases of spinal intradural haemorrhages occurring secondary to an underlying haematological disorder or an iatrogenic coagulopathy.  Coagulopathy induced spinal haemorrhage should be included in the differential diagnosis of acute paraparesis in patients with co-existent haematological disorders or undergoing anticoagulation therapy. Due to the often mixed subdural and subarachnoid bleeding patterns we have termed this entity spinal intradural-extramedullary haematoma.     

Microsurgical Treatment of Spontaneous and non-Spontaneous Spinal Epidural Haematomas: Neurological Outcome in Relation to Aetiology

Summary  Background. This retrospective study evaluated the neurological outcome of 26 patients with spontaneous and non-spontaneous spinal epidural haematoma (SEH) who underwent microsurgical clot removal. It was the objective of the present study to investigate whether the aetiology of the SEH has an influence on the neurological outcome.  Methods. The medical records and radiological investigations of 26 patients with SEH were re-examined, and the latency between symptom onset and operation, and the size of the haematoma were determined. Motor and sensory function had been evaluated before surgery and 90 days after discharge.  Findings. Fourteen patients with non-spontaneous SEH and 12 patients with spontaneous SEH were identified. After surgery, neurological deficits improved in 9 of the patients with spontaneous (75%) and in 13 of the patients with non-spontaneous SEH (93%). In cases of spontaneous SEH, the median latency between symptom onset and operation was longer (72 hrs vs 7 hrs) and the median extent of the haematoma was larger (3.5 vs 2 spinal segments), than in the non-spontaneous cases.  Interpretation. Neurological outcome seems to be related to the aetiology of the SEH. Better outcome was observed in patients with surgically treated non-spontaneous SEH. Two explanations for this finding are worth considering. First, patients with non-spontaneous SEH usually are already under medical surveillance and can undergo medullary decompression more rapidly. Second, the compression of the spinal cord is possibly less severe in non-spontaneous SEH because of their smaller size.     

Burr Hole Evacuation of Chronic Subdural Haematomas Followed by Continuous Inflow and Outflow Irrigation

Summary  Chronic subdural haematomas are prone to recollect, increasing the risk of further complications and death. Burr hole evacuation followed by continuous irrigation of a Ringer solution into the remaining subdural cavity, allows remaining blood to be washed out and the brain to re-expand.  This technique was compared with burr hole evacuation either without or with a passive drainage and craniotomy, respectively.  Reformation of haematomas after continuous irrigation occurred in 2,6% (2/77); more than a twelve (32,6%; 15/46) and a nine (23,8%; 5/21) times rate reduction compared to burr hole evacuation without and with passive drainage, respectively. Compared to the craniotomy results, the rate dropped seventeen times (44,4%; 4/9).  Expect from the two rebleedings in 77 haematomas operated on through burr holes followed by irrigation, all patients recovered including nine recurrent haematomas re-operated on by this method.  Recurrent haematomas operated on through burr hole evacuation alone or with insertion of a passive drainage, recollected in 50% (2/4) and 33,3% (2/6). Similar rate after craniotomies was 11,1% (1/9).  Neither infections nor deaths followed burr hole evacuation combined with continuous irrigation, whereas 5,3% (2/38) and 5,9% (1/17) suffered from empyema after burr hole evacuation alone or combined with a passive drainage, respectively. Five (9,1%) of these 55 patients died either from empyemas (three) or rebleedings (two).  Recurrent haematomas evacuated through a craniotomy had no complications from infections.  Compared to other methods, continuous irrigation reduces the need for re-operation significantly by preventing haematoma recurrence and empyema formation. Contrary to other surgical techniques, haematoma recurrence after second time surgery did not occur.     

Correlation of Computed Tomography Findings and Serum Brain Damage Markers Following Severe Head Injury

Summary  The objective of our study was to investigate the association between the initial levels of serum S-100B protein and neuron specific enolase and the severitiy of radiologically visible brain damage and outcome after severe head injury.  Admission computed tomography (CT) scans of forty-four patients with severe head injury were analysed. Initial levels of S-100B protein and neuron specific enolase were compared between the different outcome groups at 6 month, the different categories of the Marshall classification, the presence of traumatic subarachnoid haemorrhage, the type of haematoma and the volume of contusion.  Serum S-100B was significantly higher in patients with unfavourable outcome (1.1 μg/1 versus 0.3 μg/1, p<0.005, Mann-Whitney U test). In diffuse injury, unfavourable outcome significantly increased with higher Marshall grades (p<0.05). There was a significant correlation between the four grades of diffuse injury and initial serum S-100B protein (r=0.48, p<0.001). Patients with focal mass lesions and a favourable outcome after 6 month had significantly lower S-100B values than those who had an unfavourable outcome (0.51 μg/l versus 1.3 μg/1, p<0.05). A significant correlation was demonstrated between the volume of contusion visible on CT scans and serum S-100B (r=0.58, p<0.001).  In our study, initial serum S-100B protein was a powerful predictor of outcome even within the same category of radiologically visible brain damage. Serum S-100B protein may provide independent information about the severity of primary brain damage after head injury.     

The Factors Influencing Haematoma Volume due to Arteriovenous Malformations

Summary  Haemorrhage due to cerebral arteriovenous malformations (AVMs) varies from massive, requiring urgent operations, to clinically silent. The present study was designated to identify factors influencing haematoma size, and the pathophysiological mechanisms of massive haemorrhage were studied. 55 patients with intracerebral haematomas due to supratentorial AVMs were included in this study. Angiographic and clinical findings were retrospectively evaluated in relation to haematoma size.  Statistical analysis demonstrated that small size and the presence of only one draining vein were high risk factors for massive haemorrhage. The haematoma volume in small AVMs (30±4 cm³) was significantly larger than in other AVMs (7±3 cm³) (p=0.0005). AVMs with only one draining vein were associated with massive haematoma volume as compared to AVMs with two or more draining veins (30±4 versus 11±3 cm³, p=0.0023).  Our previous study demonstrated that feeding artery pressure (FAP) was significantly higher in AVMs with haemorrhage than in those without, as was draining vein pressure (DVP), and FAP and DVP were inversely related to the number of draining veins and the size of the AVMs. Thus, in small AVMs and AVMs with only one draining vein, local increase in DVP may thus contribute to massive haemorrhage.     

Local Coagulofibrinolysis in the Postsurgical Recovery of Patients with Chronic Subdural Haematoma

Summary  Postoperative recovery of patients with chronic subdural haematoma (CSH) was investigated by comparing pre- and postoperative coagulant and fibrinolytic activity in the haematoma contents of 15 patients with SCH. Patients in this study were treated draining the haematoma cavity without irrigation, a procedure dubbed the closed drainage. Haematomas were collected during, and 24 hrs after, surgery. Postoperative fibrinolytic activity was lower than that observed pre-operatively. In particular, levels of tissue plasminogen activator activity (TPA), and fibrin and fibrinogen degradation products (FDP) all decreased. In contrast, coagulant activity increased postoperatively.  This paper will discuss the role of local coagulofibrinolysis in the postoperative recovery of CSH patients.     

Spinal Subdural and Epidural Haematomas: Diagnostic and Therapeutic Aspects in Acute and Subacute Cases

Summary  Background. The diagnosis of spontaneous spinal haematomas mainly depends on magnetic resonance imaging. This study evaluates the MRI characteristics of spinal epidural and subdural haematomas. The results were correlated with medical history, coagulation abnormalities and therapeutic outcome to provide guidelines for early diagnosis and treatment of spinal epidural and subdural hematomas.  Summary of Background Data. Imaging signs of epidural and subdural haematomas have been reported before, however without special attention to the differential-diagnostic and therapeutic implications of haematoma localisation.  Method. Seven patients (3 women, 4 men, age range 55–86 years) with acute progressive neurological deficits and without a history of severe trauma were studied. In all cases neurological examinations were performed after admission followed by MRI studies with T2 and T1 weighted images, before and after administration of contrast agent. Spinal angiography was performed twice to exclude a vascular malformation. All patients underwent open surgery.  Findings. Acute and subacute hematomas were detected once in the cervical spine, in five cases in the thoracic region and once in the lumbar region. The hematomas had an epidural location in three cases and a subdural in four. In the thoracic region subdural haemorrhage was much more common than epidural hematomas. Subdural blood collections were mainly found ventral to the spinal cord. Epidural haemorrhage was always located dorsal to the spinal cord. The evaluation of the haematoma localisation may be difficult occasionally, but delineation of the dura is frequently possible in good quality MRI. The clue to the diagnosis of ventrally located subdural haemorrhage is the absence of the “curtain sign”, which is typical for epidural tumours.  Interpretation. Spontaneous spinal hematomas are frequently located in the thoracic spine. Subdural spinal haemorrhage is more frequent than epidural. Epidural haemorrhage is frequently located dorsal to the spinal cord because of the tight fixation of the dura to the vertebral bodies.     

Neuropsychological Follow-up of Twenty Two Adult Patients After Surgery for Craniopharyngioma

Summary  The optimal management of craniopharyngioma today remains an unconcluded debate. This prospective study examines the cognitive status and quality of life of 22 patients one year after surgery for craniopharyngioma.  Pterional approach (5 left, 15 right) was used in 20 patients (90%), whereas two were operated on using a rhinoseptal approach.  Neuropsychological examination was performed twelve months after the operation. For twelve patients, neuropsychological examination was performed before operation.  The preoperative evaluation revealed that six patients had impaired neuropsychological testing with memory and frontal dysfunction. Four of these patients have no postoperative neuropsychological defect.  After surgery, there were 5 patients in whom abnormalities could be detected on the extended psychometric assessment: two were severe (a Korsakoff's syndrome and a memory defect associated with an intellectual deterioration), and three moderate (recent memory defects with frontal dysfunction, isolated learning defects). Four patients of the 22 were not able to return to their pre-illness activity.  The present evaluation emphasizes that a good quality of life and neuropsychological performance were maintained in the majority of patients. Preoperative frontal dysfunction is probably correlated to tumour location, and precisely to the interruption of the direct efferent projections from the frontal cortex to the hypothalamus.  Postoperative alterations of neuropsychological function were noticed only in patients with pterional approach. These patients had a poor surgical outcome, preoperative neuropsychological defects or treatment combined with radiotherapy. The two patients who were operated on using a rhinoseptal approach had no neuropsychological deficit. But this surgical approach is best reserved for patients with smaller intrasellar tumours. Further studies are needed to evaluate the neuropsychological advantage of these different approaches.     

Pure Acute Subdural Haematoma Without Subarachnoid Haemorrhage Caused by Rupture of Internal Carotid Artery Aneurysm

Summary  A 52-year-old female presented with disturbance of consciousness and clinical signs of tentorial herniation. Computed tomography showed a pure acute subdural haematoma (SDH) over the left convexity without subarachnoid haemorrhage. Cerebral angiography showed a saccular aneurysm at the junction of the left internal carotid artery and the posterior communicating artery. Surgery to remove the haematoma and clip the aneurysm showed the rupture point was located in the anterior petroclinoid fold (subdural space). The patient recovered without neurological deficits. Pure SDH caused by ruptured aneurysm is rare. Rupture of an aneurysm adhered to either the dura or falx and located in the subdural space may cause pure SDH. Therefore, ruptured intracranial aneurysm should be considered as a cause of non-traumatic SDH. Immediate removal of the SDH and aneurysmal clipping is recommended in such patients, even those in poor neurological condition.     

Acute subdural haematoma from ruptured intracranial aneurysms

Summary Acute subdural haematoma (SDH) secondary to a raptured intracranial aneurysm is a rare event. Out of a total of 292 patients with a verified aneurysm (period 1986–1992) in five cases SDH was the diagnosis on CT-evaluation. One patient was in such a bad condition that no treatment was indicated. The remaining four patients were operated on: craniotomy and haematoma evacuation in two cases, craniotomy for haematoma evacuation and aneurysm-clipping in the other two cases. Two patients died and two achieved a good outcome.     

Volume of chronic subdural haematoma: Is it one of the radiographic factors related to recurrence?

Background

Recurrence of chronic subdural haematoma (CSDH) is a significant issue in neurosurgical practice, and to distinguish individuals at high risk is important. In this study, we aim to clarify the relationship between quantitative haematoma volume and recurrence of CSDH.

Methods

For this two-year retrospective study, 94 patients with CSDH were enrolled and all underwent burr-hole craniostomy with closed-system drainage. The volume of haematoma before surgery was quantitatively analysed by computed tomography (CT) of the brain. The patients were subdivided into 2 groups based on whether recurrence of CSDH was present or not. We investigated the intergroup differences in the volume of haematoma and other radiographic parameters.

Results

Recurrence of CSDH was identified in 13 of 94 patients (14%). Univariable analysis of CT features revealed significant differences in the volume of haematoma, bilateral cerebral convexity, and layering of the haematoma. To adjust for the confounding effect, these 3 parameters were entered into multivariable logistic regression analysis. Ultimately, neither the volume of haematoma (p = 0.449) or bilateral cerebral convexity (p = 0.123) was relevant in this model. Only the presence of layering of the haematoma was independently associated with recurrence of CSDH (p = 0.009).

Conclusion

The volume of CSDH is not related to recurrence in patients undergoing burr-hole craniostomy with closed-system drainage. Layering of the haematoma was the only independent risk factor on CT images for recurrence of CSDH in our series.     

Regrowth of Residual Ruptured Aneurysms Treated by Guglielmi's Detachable Coils Which Demanded Further Treatment by Surgical Clipping: Report of 7 Cases and Review of the Literature

Summary. Summary.   Object: The management of intracranial aneurysms has truly evolved after the introduction of endovascular treatment by Guglielmi Detachable Coils (GDC). In our department, for every case (ruptured or unruptured aneurysm) we discuss in the first place endovascular treatment. When coiling is feasible, it is done as a first choice. If not (intracranial compressive haematoma, coiling unfeasible or dangerous), the patient is operated upon. Failure of the endovascular technique, like incomplete treatment and regrowth of the residual sac, becomes a subject of discussion. Some cases need complementary treatment for large or unstable residual aneurysm.   Methods: Thus, between 1997 and 2000, 59 ruptured aneurysms were treated using an endovascular method by means of GDC. In 15 of this cases complementary treatment was needed, due to the size or instability of the residual aneurysm. In 8 cases a new embolization was possible and in 7 cases a complementary surgical procedure was needed, due to the impossibility of further endovascular treatment.   Results: Out of these 7 cases who were operated upon after coiling, clipping of the residual neck was possible in 4 cases; in 3 cases clipping was impossible due to the partial filling of the aneurysm neck by the coils. In these 3 cases, a ligation of the residual neck, associated with coagulation of the sac was performed.   Discussion: The difficulty of the treatment of an residual aneurysm after coiling is discussed as well as those surgical techniques alternative to clipping (wrapping or coagulation of the residual sac).     

Eight year outcome after surgery for lumbar disc herniation: a comparison of reoperated and not reoperated patients

Summary  A retrospective study of 211 patients with unilateral sciatica operated on for lumbar disc herniation during 1988 and 1989 was performed in order to compare the results of reoperated patients with the results of patients operated on only once. The patients completed a standardized questionnaire in 1997 which included questions about reoperations, back and leg pain, functional status and disability pension. Outcome scores were calculated, giving values from 0 (no pain/normal function) to 100 (totally disabled).  A follow-up status of 80.1% was obtained; 163 patients answered the questionnaire while six patients had died. 23.9% of the patients (n=39) had been reoperated on. A recurrent disc herniation at the same level was suspected before the reoperation in 18.4%, but a recurrence was found in only 8.6%. 3.7% were reoperated on more than once. Outcome score was worse among “reoperated” patients (median 45.0, range 0–94) than among patients who only had the primary operation (median 10.5, range 0–81) (P<0.001). In addition, 34,3% of the “reoperated” patients received a disability pension compared to 9,9% of the patients not reoperated on (P<0.01). Patients reoperated upon at the same level without peroperative signs of recurrent disc herniation, had an outcome score of 53.0 (range 0–82) compared to a score of 30.0 (range 0–66) in patients with a confirmed recurrence (P<0.05). The percentage of disability pension was 53.8% versus 9.1%, respectively, for those two groups (P<0.05).  Eight years after operation for lumbar disc herniation, the outcome was significantly worse in “reoperated” patients than in patients operated on once. In addition, reoperated patients with peroperatively confirmed recurrence of the same disc, seemed to have a better outcome than patients without peroperative signs of a recurrence.     

Decompressive craniectomy for the management of patients with refractory hypertension: should it be reconsidered?

Summary. Summary.   Introduction: The management of refractory post-traumatic cerebral oedema remains a frustrating endeavor for the neurosurgeon and the intensivist. Mortality and morbidity rates remain high, despite refinements in medical and pharmacological means of controlling intracranial hypertension.   Method and Material: In this retrospective study we have evaluated the efficacy of decompressive craniectomy as a last resort therapy, from the data of nine patients with severe brain injury and delayed cerebral oedema (diffuse injury type III), treated between January 1997 and September 1999. The following parameters were considered: age, Glascow Coma Scale, injury severity, intracranial pressure, CT findings, pupil reaction/posturing. Follow-up period was over at least 2 years and outcome measured on the GOS.   Results: Patients have been operated on post-trauma median day 3, mean age 26±9, GCS 7±3.7, mean APACHE II 16±6.4, mean ISS 27.8±16.1, mean preoperative ICP 37.7±10.0, mean postoperative ICP 18.1±16.01. Seven patients have been operated by a frontotemporoparietal approach (six of them bilateral, one unilateral) and two patients have been operated on by a bilateral subtemporal approach. Mortality rates 22%, severe disability 11%, good recovery 66%.   Discussion: Patients with STBI, developing delayed intracranial hypertension caused by diffuse cerebral oedema, definitely benefit from craniectomy when current medical treatment has failed. The encouraging results of outcome in this and more recent studies, indicate the need for a multi-institutional randomized prospective study evaluating early indicators of raised ICP, timing, efficacy of treatment, operative technique and complications of decompressive craniectomy. Published online August 12, 2002     

Minor Head Injuries: One Year Experience According to the New Italian Guideline

Summary  Background. The data concerning a consecutive series of 4,536 adult patients suffering from minor head injuries treated at the Department of Neurosurgery over a period of one year are reported.  Method. The patients' age, sex and the circumstances of the injury have been taken into consideration. The patients, according to the new method, were divided into four groups.  Group 0 (3,864 patients) included all patients with Glasgow Coma Scale (GCS) score 15. They did not present any clinical features such as loss of consciousness (LOC), post-traumatic amnesia (PTA), headache or vomiting. No risk factors (RF) such as coagulopaties, alcoholism, drug abuse, epilepsy, previous neurological treatment or disabled elderly patients were detected.  Group 1 (600 patients) included patients with GCS score 15. The patients presented one or more clinical features (LOC, PTA, headache, vomiting). No RF were presented.  Group 2 (24 patients) included patients with GCS score 14 with or without clinical features (LOC, PTA, headache, vomiting) and with or without RF.  Group 0-1R (48 patients) included patients with GCS score 15 with or without clinical features (LOC, PTA, headache, vomiting). All of them presented RF.  The presence of focal neurological signs, open injury and GCS score≦13 were considered criteria for exclusion.  Findings. All the patients from groups 1, 0-1R, 2 and 187 patients from group 0 underwent CT scan for a total of 859 exams which are analyzed and discussed. 458 patients were admitted and are divided as follows: 216 from group 0, 192 from group 1, 26 from group 0-1R and all the 24 belonging to group 2. Six patients were treated surgically (3 extradural haematomas, 2 lobe contusions, 1 acute subdural haematoma) and one of them (0.02% of the total) died (extradural haematoma). The patients who were not admitted were sent home with an information sheet after at least a six hour observation period.  Interpretation. The authors draw the conclusion that they have evaluated the applicability and efficacy of guidelines, developed by the study group on head injury of the Italian Society of Neurosurgery [19]. A critical part of our guidelines is not only to identify all the intracranial lesions, but to identify patients harbouring relevant intracranial mass before clinical deterioration.     

Continuous irrigation-drainage of the subdural space for the treatment of chronic subdural haematoma. A prospective clinical trial

Summary Thirty seven adult patients which chronic subdural haematoma were randomized into two groups. Eighteen patients served as controls and underwent evacuation of the haematoma via burr holes and a gravity dependent closed-system drainage. Nineteen patients comprised the study group. These patients had a continuous irrigation-drainage system installed in an attempt to facilitate the removal of fibrinolytic substances present in the haematoma fluid and to try to reduce the rate of rebleeding from the haematoma membranes. No differences were found between the pre- and post-operative clinical status, haematoma volumes and the degree of CT changes between the two groups. The complication rate was similar in the two groups. One patient in the study group and three patients in the control group required an extended period of drainage (24–48 hours) prior to the removal of the drains. All patients improved following the procedures. Within 30 days post the initial evacuation of the chronic subdural haematoma, re-operation was required in only one patient in the study group as opposed to four of the controls. This difference was not however statistically significant. When the need for re-operation was combined with the need for extended drainage period, a significant difference was shown in favour of the study group. These results indicate that drainage combined with continuous irrigation of the subdural space does not affect the clinical outcome of the patients, but significantly reduces the frequency of inadequate drainage of the haematoma and prevents longer drainage periods and repeated operations.