Features of chronic subdural haematoma developed from definitely identified acute subdural haematoma

Follow-up results for 13 cases of acute subdural haematoma, which were identified by CT scan within two days of head injury and treated conservatively, were classified into two groups: In the first group of seven cases the acute subdural haematoma disappeared spontaneously within two weeks; in the second group the other six cases revealed clinical signs and CT scan findings which were identical to chronic subdural haematoma and underwent surgery within three weeks after the head injury. This group showed low ICP signs, such as the chronic stage of cerebral thrombosis, atrophic brain or subdural fluid collection with acute subdural haematoma at the initial CT scan, and most of these cases had only minor head injury. Common features of the operative findings in this second group, in which chronic subdural haematoma developed, included the identification of an external haematoma capsule based on the fibrin layer and granulation tissue beneath the dura. Also, fluid type haematoma was present under these structures, but no inner membrane of the haematoma could be identified other than the non-transparent white arachnoid membrane. Our results indicate the importance of a low ICP in determining whether or not acute subdural haematoma progresses to chronic subdural haematoma.     

Posttraumatic diffuse cerebral lesions. Relationship between clinical course, CT findings and ICP.

One hundred and fifty patients with posttraumatic diffuse cerebral lesions were reviewed. Criteria of inclusion were immediate coma and CT appearance of diffuse lesions, that were classified as follows: (a) Diffuse axonal injury (70 cases): patients with normal CT scan (50 cases) and patients with shearing injury (focal hemorrhages in corpus callosum, basal ganglia and brain stem; gliding contusions) (20 cases); (b) Diffuse brain swelling (80 cases): reduced or absent lateral ventricles, absence of 3rd ventricle and basal cisterns. Many of these patients had either subarachnoid haemorrhage or subdural blood effusion. Clinical course and mortality rate were in a ranking order in the considered groups. Patients with normal CT had a less severe coma and a better outcome than patients with shearing injury and diffuse brain swelling. There was evidence of high intracranial pressure in 75% of the patients with brain swelling, whereas no patient with normal CT had ICP elevation. Diffuse axonal injury represents a primary posttraumatic diffuse lesion. Secondary vascular involvement, due to hypoxia, shock and other unknown causes, is responsible for the appearance of vasoparesis, hyperemia and diffuse brain swelling.     

Acute subdural haematoma in the conscious patient: Outcome with initial non-operative management

Summary We have retrospectively reviewed 23 conscious patients, in whom a CT scan diagnosis of acute subdural haematoma was made, and in whom craniotomy for evacuation was not initially performed. These highly selected patients represent 3% of 837 patients with acute subdural haematoma, presenting over a five year, eight month period to the Institute of Neurological Sciences, in Glasgow (1986–1991). Patients with any other associated intracranial abnormalities, such as cerebral contusions, as shown on CT, were excluded from this report. All patients were followed by serial CT scanning, and neurological assessments.Cerebral atrophy was present in over half of the sample. In 17 of our patients, the acute subdural haematoma resolved spontaneously, without evidence of damage to the underlying brain, as shown by CT or neurological findings. Six subsequently required burr hole drainage of a hypodense liquid subdural haematoma. In each of these patients, haematoma thickness was greater than 10 mm. Haematoma volume was significantly larger (53±6 ml versus 32±2 ml) in the group who came to operation. The mean delay between injury and operation in this group was 15 days.We conclude that certain conscious patients with small acute subdural haematomas, without mass effect on CT, may be safely managed conservatively.     

Diffuse Axonal Injury (DAI) is not Associated with Elevated Intracranial Pressure (ICP)

Summary Objective. Traditionally, intracranial pressure (ICP) monitoring has been utilized in all patients with severe head injury (Glasgow coma score of 3–8). Ventriculostomy placement, however, does carry a 4 to 10 percent complication rate consisting mostly of hematoma and infection. The authors propose that a subgroup of patients presenting with severe head trauma and diffuse axonal injury without associated mass lesion, do not need ICP monitoring. Additionally, the monitoring data from ICP, MAP, and CPP for a comparison severe head injury group, and subgroups of DAI would be presented. Materials and methods. Thirty-six patients sustaining blunt head trauma and fitting our strict clinical and radiographic diagnosis of DAI were enrolled in our study. Inclusion criteria were severe head injury patients who did not regain consciousness after the initial impact, and whose CT scan demonstrated characteristic punctate hemorrhages of <10 mm diameter at the greywhite junction, basal ganglia, corpus callosum, upper brainstem, or a combination of the above. Patients with significant mass lesions and documented anoxia were excluded. Their intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were compared to a control group of 36 consecutive patients with severe non-penetrating non-operative head injury, using the Analysis for Variance method. Results. Eighteen (50.0%), six (16.7%), and twelve (33.3%) patients had types I, II, and III DAI, respectively. The admission Glasgow Coma Score (GCS) was higher for types I and II than for type III DAI. ICP was monitored from 23 to 165 hours, with a mean ICP for 36 patients of 11.70 mmHg (SEM=75) and a range from 4.3 to 17.3 mmHg. Of all ICP recordings, of which 89.7% (2421/2698) were ≤20 mmHg. Average mean arterial pressure (MAP) was 96.08 mmHg (SEM=1.69), and 94.6% (2038/2154) of all MAP readings were greater than 80 mmHg. Average cerebral perfusion pressure (CPP) was 85.16 mmHg (SEM=1.68), and 90.1% (1941/2154) of all CPP readings were greater than 70 mmHg. This is compared to the control group mean ICP, MAP, and CPP of 16.84 mmHg (p=0.000021), 92.80 mmHg (p=0.18), and 76.49 mmHg (p=0.0012). No treatment for sustained elevated ICP>20 mmHg was needed for DAI patients except in two; one with extensive intraventricular and subarachnoid hemorrhage who developed communicating hydrocephalus, and another with ventriculitis requiring intrathecal and intravenous antibiotic treatments. Two complications, one from a catheter tract hematoma, and another with Staph epidermidis ventriculitis, were encountered. All patients, except type III DAI, generally demonstrated marked clinical improvement with time. The outcome, as measured by Glasgow Coma Score (GCS) and Glasgow Outcome Score (GOS) was similarly better with types I and II than type III DAI. Conclusion. The authors conclude that ICP elevation in DAI patients without associated mass lesions is not as prevalent as other severe head injured patients, therefore ICP monitoring may not be as critical. The presence of an ICP monitoring device may contribute to increased morbidity. Of key importance, however, is an accurate clinical history and interpretation of the CT scan.     

Post-traumatic diffuse axonal brain injury. Analysis of 78 patients studied with Computed Tomography

Summary A group of 78 severe head injury patients showing computerized tomography (CT) findings of the so-called diffuse axonal injury is analyzed. These patients represent 20% of the authors' series of severe head injury. Twenty-three patients showed small intraparenchymal haemorrhages in the CT scan study, 15 intraventricular haemorrhage and 40 patients had both intraparenchymal and intraventricular haemorrhages. Signs of brainstem haemorrhagic contusion were seen in 29 (38%) patients. Generalized brain swelling superimposed on the above findings was present in 75% of the cases. Raised intracranial pressure, which was found in 50% of the patients, correlated with the presence of ventriculocisternal collapse in the CT scan and an unfavourable outcome. Only 4 patients in this series made a good recovery, 13 developed a moderate disability, 11 a severe disability, 12 became vegetative and 38 (49%) died. The prognosis with this post-traumatic lesion is the worst in the authors' severe head injury series after excluding cases with subdural haematoma.     

Traumatic intracerebral lesions without extracerebral haematoma in 218 patients

Summary 218 of the 852 patients in the HIT-2 study of head injury had intracerebral lesions only. They were analysed to get more information on the optimal treatment of these severely injured patients. The initial CT scans were reviewed to exclude patients with extracerebral lesions, and to make a radiological diagnosis of contusion, contusion under a depressed fracture, diffuse axonal injury, or intracerebral haematoma. Deterioration after admission to hospital was seen in 71% of patients. Patients with contusions, and contusions from depressed fractures in particular showed a worse outcome than expected, while patients with diffuse injury had a tendency to improve rather than to deteriorate. Patients with intracerebral haematoma seemed to improve if the mass was evacuated. Nimodipine had an impact only in patients with contusions. Our findings mandate surgical evacuation of contusions and intracerebral haematomas in patients with lesions larger than 20 ml who also have radiological signs of a mass effect. Regardless of an apparently good clinical state in the early phase, intracerebral lesions larger than 50 ml seemed to benefit from surgery as compared to nonsurgical treatment.The findings indicated that a further refinement of diagnostic criteria may enable individually tailored head injury treatment to interfere with most important pathogenic mechanisms. More accurate diagnoses will improve head injury treatment and outcome, and are a prerequisite for making successful pharmaceutical trials of head injury in the future.     

Outcome of patients with diffuse axonal injury: the significance and prognostic value of MRI in the acute phase

BACKGROUND: To compare the magnetic resonance imaging (MRI) findings in the acute phase with outcome in patients with diffuse axonal injury (DAI). METHODS: A group of 33 patients with closed head injury and discrepancy between the apparently normal computed tomographic scan findings and their neurologic statuses were studied with MRI during the first 48 hours. Among them, 24 were found to suffer from DAI-type lesions. According to the Glasgow Coma Scale (GCS), 19 patients suffered from severe head injury (GCS score <8) and 5 patients had moderate head injury (GCS score of 9-12). Four MRI sequences in various planes were applied. Patients were divided into three groups, according to staging described in the literature. RESULTS: In five patients, MRI demonstrated nonhemorrhagic DAI lesions stage 1. In 11 patients, findings were consistent with DAI lesions stage 2, eight nonhemorrhagic and three hemorrhagic. Eight patients showed DAI lesions stage 3, six of which were nonhemorrhagic. CONCLUSIONS: MRI is more sensitive compared with computed tomography in the detection of traumatic brain lesions, especially the nonhemorrhagic DAI. The presence of hemorrhage in DAI-type lesions and the association with traumatic space-occupying lesions is a poor prognostic sign. Isolated nonhemorrhagic DAI-type lesions are not associated with poor clinical outcome.     

Is computed tomographic scanning necessary in patients with tentorial herniation? Results of immediate surgical exploration without computed tomography in 100 patients

Computed tomographic (CT) scans are performed on virtually all patients with severe head injury at the time of admission. Because of the time involved in obtaining these studies, the evacuation of significant intracranial mass lesions is delayed. To avoid such delays, the authors performed burr-hole exploration for the diagnosis of intracranial hematomas before CT scans were obtained in 100 consecutive head-injured patients with clinical signs of tentorial herniation or upper brain stem dysfunction upon admission to the emergency room. Patients in whom a hematoma was discovered had a craniotomy for evacuation of the clot; those in whom the exploration was negative had a CT brain scan immediately after operation. Burr-hole exploration revealed extracerebral mass lesions in 56 patients. In 38 patients, the exploration was negative, and postoperative CT scanning showed no significant hematoma. Of 6 patients in whom the CT scan demonstrated extraaxial hematomas requiring surgical evacuation, 4 had subdural hematomas that were missed because the exploration was incomplete; 1 patient had an epidural hematoma and 1 had a subdural hematoma contralateral to a craniotomy on the side of a positive initial burr-hole exploration. Our results indicate that the relatively small subgroup of head-injured patients with early tentorial herniation or upper brain stem compression have a high incidence of immediate extraaxial hematomas and a low incidence of intracerebral hematomas. This is particularly true of patients over 30 years of age and those who suffer low speed trauma, such as falls and vehicle-pedestrian accidents.     

Acute subdural haematoma mimicking an epidural haematoma on a CT scan

This paper reports an acute subdural haematoma mimicking an epidural haematoma as seen on a non-enhanced computerized tomography (CT) scan of the head in a patient who had sustained a traumatic head injury. The patient had undergone a craniotomy 4 years prior to the injury described here.     

Temporal lobe lesions in head injury

Summary In cases of closed head injury temporal lobe lesionse.g. contusion, laceration, pulping, or intracerebral haematoma frequently result in an expanding process. These are frequently associated with an overlying subdural haematoma. Eighty five cases of such lesions from a consecutive series of 1,000 cases of head injury have been analyzed. The lesions are caused by severe injury resulting in loss of concsiousness and skull fracture. Most of them are contre-coup lesions. Clinically they manifest themselves like any other acute or subacute intracranial hematoma. The majority of the patients have contralateral hemiparesis and pupillary abnormalities. Carotid angiography is valuable for diagnosis. These lesions are likely to be missed when exploratory burr holes are made or, are erroneously diagnosed as acute subdural haematoma or brain oedema. Smaller lesions, not showing progressive deterioration, may respond to conservative treatment. However, surgical decompression is essential in most cases. A fronto-temporal osteoplastic craniotomy or a large Scoville trephine hole is essential to deal with these lesions adequately.     

Justification for evacuating acute subdural haematomas in patients above the age of 75 years

The author has reviewed the outcome of 27 patients aged 75 years and over who had an operation for acute traumatic subdural haematoma at Frenchay Hospital Bristol over a 10-year period. There were 15 men and 12 women with a mean age of 79.2 years. The outcome at 6 months was determined using the Glasgow Outcome Score. Of the patients, 15 per cent made a good recovery, 15 per cent a poor recovery and 70 per cent died. The influence of age, sex, mechanism of injury, preoperative Glasgow Coma Score (GCS), pupillary reactivity to light, skull and limb fractures, clinical course, CT scan appearance and timing of operation were analysed in relation to the outcome. The results showed that a preoperative GCS of 4 or less and unilateral pupillary dilatation and non-reactivity to light were not compatible with good survival in the very elderly patient with acute subdural haematoma. Under these circumstances, operation is not justified. The prognosis was worse in patients who were unconscious immediately after injury and with a CT scan showing a subdural haematoma and a haemorrhagic contusion which required urgent early intervention. The prognostic indicators present may prove useful in the selection of patients for active surgical intervention.     

Subdural Haematoma. A Rare But Life-Threatening Complication after Spinal Anaesthesia

A 70-year-old patient developed severe headache after spinal anaesthesia. He was treated with an epidural autologous blood patch with only temporary relief. Three weeks after the spinal anaesthesia, the headache became more intense and was accompanied by nausea and vomiting. A second epidural blood patch was performed without effect. The patient became unconscious and an acute CT scan revealed a large subdural haematoma. This was immediately evacuated and the patient made a good recovery. This case demonstrates that subdural haematoma should be considered as a possible aetiology in severe postspinal headache.     

螺旋CT对弥漫性轴索损伤的诊断价值

目的分析脑弥漫性轴索损伤(diffuse axonal injury,DAI)的CT表现,评价螺旋CT对DAI的诊断价值。方法回顾性分析43例DAI患者的CT表现。结果 DAI在CT影像上可见弥漫性脑肿胀,皮层下及脑深部小出血灶,中线结构无明显移位。43例患者检出58个病灶,非出血性病灶37个,呈斑片状大小不一低或稍底密度影,边界不清晰;出血性病灶21个,呈斑片状大小不一高密度影。结论螺旋CT检查是DAI的影像学诊断依据之一,结合临床能协助判断伤情,并为动态观察预后提供帮助。     

Computed tomography in diagnosis of diffuse axonal injury

Diffuse axonal injury (DAI) has been described in instances of prolonged traumatic coma on the basis of the neuropathological findings, but the same findings are also found in patients with cerebral concussion. Experimental studies confirm that the quality of survivors following trauma is directly proportional to the amount of primarily injured-axon. When the injured axon lies in a widespread area of the brain, outcome for the patient is always poor. In a series of 260 severely head-injured patients, based on their poor outcome, 69 (27%) were diagnosed as DAI. Because of their relatively good outcome, eighty-two patients (32%) were classified into non-DAI group. The predominant CT finding of DAI patients was intraparenchymal deep-seated hemorrhagic lesion. This was observed in 28 patients (41%). Normal CT was also observed in 11 patients (16%). On the other hand, 8 of the non-DAI group (10%) manifested deep-seated lesions. Diffuse cerebral swelling (DCS) appeared in both groups in the same incidence. Subarachnoid hematoma in the perimesencephalic cistern (SAH (PMC] and intraventricular hematoma (IVH) were observed in 64% of the DAI group, and in 23% of the non-DAI group. The available evidence indicates that various types of hematoma seen in the deep-seated structures of the brain do not have an absolute diagnostic value, but the frequency of hematoma is thought to increase in proportion to the amount of injured-axon.     

Changes produced by CT scanning in the outlook of severe head injury

Summary This is a study of the changes that have occurred in the field of severe head injury since the advent of CT scanning, comparing two homogeneous series of patients selected by clinical status (Glasgow Coma Scale 8), namely a series of 1,000 cases admitted to our Department between 1973 and 1976, already published in this Journal³¹, and one of 385 cases cared for between 1979 and 1980, when CT scanning had become generally available. The two series of patients compare very closely in many respects, particularly in the incidence of surgical cases. In the more recent series the overall outcome was better both in surgical and in non-surgical cases. Among patients in the CT scan series the incidence of brain contusion associated with haematoma was greater than that of pure subdural haematomas. In non-surgical patients the CT scan, unlike cerebral angiography, afforded better identification of traumatic lesions and the grouping of patients into homogeneous categories correlating with a given outcome.On admission, cerebral angiography and CT scanning were equally effective in detecting lesions of surgical import; later in the course of the illness, however, CT scanning proved far more effective in detecting changes, with fully 15% of the patients being referred for surgery in the light of repeat CT scan findings as opposed to only 4% undergoing surgery on the indications of repeat angiography. Also, in the new series the mean interval from injury to surgery was shorter, with 64% of patients being operated on within 6 hours of the injury. The incidence of lucid intervals dropped from 30% in the first series to 16% in the second, both among surgical and non-surgical patients.That the systematic repetition of CT scans was instrumental in preventing the worsening of clinical status is demonstrated by the fact that 54 patients treated surgically for expanding lesions were excluded from the second series because they could be treated before they reached a GCS score of 8 or less, whereas such cases were quite exceptional in the older series. The CT scan approach resulted in a material increase of surgical interventions.Overall, the comparison of these two series of cases selected only by the criterion of clinical severity fails to provide a complete expression of the impact of CT scanning on our daily dealing with severe head injuries.     

Diffusion tensor imaging fiber tractography for evaluating diffuse axonal injury

Patients with Diffuse axonal injury (DAI) frequently exhibit cognitive disorders chronically. Radiologic recognition of DAI can help understand the clinical syndrome and to make treatment decisions. However, CT and conventional MRI are often normal or demonstrate lesions that are poorly related to the cognitive disorders. Recently, diffusion tensor imaging (DTI) fiber tractography has been shown to be useful in detecting various types of white matter damage. The aim of this study was to evaluate the feasibility of using DTI fiber tractography to detect lesions in DAI patients, and to correlate the DAI lesions with the cognitive disorders. We investigated two patients with chronic DAI. Both had impaired intelligence, as well as attention and memory disorders that restricted their activities of daily living. In both patients, DTI fiber tractography revealed interruption of the white matter fibers in the corpus collosum and the fornix, while no lesions were found on conventional MRI. The interruption of the fornix which involves the circuit of Papez potentially correlates with the memory disorder. Therefore, DTI fiber tractography may be a useful technique for the evaluation of DAI patients with cognitive disorders.     

Diffuse axonal injury and early intracranial sequelae in severe head injury.

The importance of diffuse axonal injury (DAI) and early intracranial sequelae was studied in 107 patients with diffuse and focal brain injuries. Comprehensive neuropathological study was also undertaken in 24 fatal patients. The mortality rate was clearly the highest in traumatic subarachnoid hemorrhage, followed by acute subdural hematoma, cerebral contusion with delayed hematoma formation, traumatic intracerebral hematoma, diffuse cerebral swelling, DAI with classical features, and finally nearly normal on computed tomographic scans. The mean flow velocities in the middle cerebral artery recorded by transcranial Doppler ultrasound were variable in diffuse brain injury, but commonly decreased on the hematoma side depending on increased intracranial pressure and decreased cerebral perfusion pressure in focal brain injury. Deep-seated hemorrhagic lesions did not expand in diffuse brain injury, but sizable hematoma developed within 24 hours in focal brain injury. The platelet count was significantly lower in patients with poor outcomes in focal brain injury. Histological evidence of classical DAI was found in eight (50%) of 16 cases with focal brain injury. DAI of varying severity is the common subjacent lesion in patients with severe head injury, but the final outcome varies greatly with different lesion types.     

A pathogenesis of chronic subdural hematoma; it's relationship to subdural membrane]

Our report concerns 112 cases of chronic subdural hematoma (CSH). M:F ratio is 3.5:1. (Fig. 1). The etiology of CSH is as follows; mild head injury (71 pts.), post-craniotomy (3 pts.), post-V-P shunt (1 pt.) and unknown (37 pts.). All patients are diagnosed by CT scan. Twenty patients were followed up after the subdural space was expressed as low density on CT (Fig.2). 14 of these were found to have extremely thin subdural fluid collection without compression of the brain. Cisternography by using radioisotope and/or metrizamide was carried out in seven patients in whom the subdural fluid collection was found on CT, and in five of whom the dye flowing into the subdural space was retained for 24-48 hours (Fig. 3 a). For treatment, burr holes and irrigation of the hematoma was carried out and then a drain was inserted into the subdural space. The inner membrane of the chronic subdural hematoma was looked at in 19 patients during surgery. All but one showed the inner membrane totally covering the brain surface. However, in one patient the inner membrane didn't entirely cover the brain surface, suggesting that this was the condition just before the entire encapsulation of the hematoma (Fig. 4 b). It used to be considered that a blood clot in the subdural space is needed to develop a chronic subdural hematoma. However, since the introduction of CT scan, there have been many reports suggesting that chronic subdural hematoma has developed from subdural fluid collection without apparent evidence of blood clot after head injury. Therefore, it has been controversial whether the blood clot is absolutely essential to develop into the chronic subdural hematoma or not.(ABSTRACT TRUNCATED AT 250 WORDS)     

弥漫性脑肿胀临床分析(附46例报告)

目的　分析弥漫性脑肿胀 (DBS)的机理并探讨其诊断和治疗。方法　按Zimmerman的CT诊断标准对急诊 46例弥漫性脑肿胀 (DBS)患者临床资料进行研究 ,并对其诊断和鉴别诊断、治疗和预后进行分析。结果　DBS多发生于交通肇事 ,后即刻意识障碍 ,呈持续性昏迷 ,CT表现双侧大脑弥漫性肿胀 ,中线附近散在点状高密度灶。结论　DBS损伤机制与病理诊断的弥漫性轴索损伤 (DAI)是一致的 ,其致死、致残率高。     

Rapid resolution of acute subdural hematoma; report of two cases]

We reported two cases of rapid resolution of acute subdural hematoma. Case 1, a 21-year-old female, sustained head trauma and became unconscious for about 15 min. Probably she was suffering from posttraumatic amnesia for about 1 day. On admission J.C.S and G.C.S were 20 and 9 (2 + 2 + 5) points, respectively. Neurological examination showed no abnormalities. An initial computed tomography (CT) scan taken 2 hours after the injury showed a high dense subdural hematoma on the left cerebral hemisphere and hemispheric swelling. She was conservatively treated. A follow up CT scan taken 8 hours after the injury disclosed rapid disappearance of the hematoma and cerebral swelling. Case 2a 23-year-old male, sustained head trauma and became unconscious for about 30 min. On admission J.C.S and G.C.S were 1 and 14 (4 + 4 + 6) points, respectively, and slight right hemiparesis was noted. An initial CT scan taken 2 hours after the injury showed subdural hematoma of the left cerebral hemisphere and hemispheric swelling. He was conservatively treated. A follow up CT scan taken 24 hours after the injury revealed almost complete disappearance of the subdural hematoma and cerebral swelling. It was suggested that the rapid resolution of acute subdural hematoma was attributable to redistribution due to decrease of ICP, and washing out by cerebrospinal fluid.