Extradural hematomas of the posterior cranial fossa. Observations on a series of 32 consecutive cases treated after the introduction of computed tomography scanning

Traumatic posterior fossa extradural hematoma in children: a meta-analysis and institutional experience of its clinical course, treatment and outcomes

Posterior fossa extradural hematoma (PFEDH) is rare but has a greater incidence amongst children. It is also associated with a rapid deterioration. The aim of this study was to present the management of PFEDH through our institutional experience and a meta-analysis. A retrospective single institution review of all children from 2004 to 2024 who underwent craniotomy for PFEDH was undertaken. The collected variables included: demographics, type of trauma, clinical findings, computed tomography findings, and clinical course. A systematic review using Ovid Medline, Ovid Embase, and Cochrane Central Register of Controlled Trials (CENTRAL), and meta-analysis were performed. Nineteen children with PFEDH who underwent surgery were identified. All 19 (100%) patients benefited from good Glasgow Outcome Scale (GOS) score 4-5, and there were no incidences of in-hospital mortality. From the systematic review, 391 patients, across twenty-four studies and our series, were included. A total of 308 were treated with surgery, whereas 83 patients were treated conservatively. A comparative meta-analysis was not performed as the two groups were deemed too heterogeneous in clinical characteristics. Instead, single-arm meta-analyses were performed. The pooled incidence of patients initially under conservative management requiring surgery was 9.90% (95%CI 1.61;22.21%, I2 = 35.2). The incidence of good functional outcomes in patients managed surgically and conservatively were 93.68% (95%CI: 88.69;97.57%, I2 = 0.0%), and 99.99% (95%CI: 96.53;100%, I2 = 0.0%), respectively. Overall pooled of mortality in patients managed surgically and conservatively were 0.57% (95%CI: 0.00;2.87%, I2 = 0.0%) and 0.00% (95%CI: 0.00;1.18%, I2 = 0.0%). Overall, our study reiterates that pediatric PFEDH is uncommon, and patients often present atypically. Based on our institutional experience and extrapolating data from our meta-analysis of the wider literature, neurosurgical intervention is a reliable therapeutic option with good clinical outcomes.

Operative versus non-operative management of posterior fossa epidural hematoma: A systematic review and meta-analysis

BACKGROUND

Posterior fossa epidural hematoma (PFEDH) is rare, occurring in less than 3% of head injuries. It can be managed either operatively or non-operatively. Management guidelines date from 2006, without recent updates providing class III evidence.

METHOD

We searched PubMed and other databases for English language observational studies up to 2021 that compared the two treatment approaches for PFEDH and.

RESULTS

Twenty-four of the 350 references, for involving 874 patients, met the study criteria. Conservative management showed higher GOS 5 scores and lower mortality. GCS 13-15 patients were more prevalent in the conservative group. Surgical cases often involved ventriculomegaly/compression, hydrocephalus or contusion.

CONCLUSION

The study shed light on surgical versus conservative PFEDH management, although evidence is sparse. Generally, conservative methods showed better initial outcomes, and should be preferred. However, respect of individual patient traits and Brain Trauma Foundation guidelines is crucial: conservative management may not suit all cases. To enhance the evidence base, RCTs are important for optimal PFEDH management. Bridging this gap can substantially improve patient outcomes and clinical decision-making, emphasizing the need to consider both the available evidence and patient-specific factors for effective guidance.

Traumatic injury to the posterior fossa: a secondary analysis and description of case series from the NEXUS head injury dataset

Background

Traumatic brain injuries involving the posterior fossa are rare and case reports indicate they often result in severe outcomes. We seek to describe characteristics and outcomes of traumatic posterior fossa injuries.

Methods

We performed a planned secondary analysis of all patients with posterior fossa injuries enrolled in the NEXUS head computed tomography (CT) validation study dataset. The dataset includes prospectively collected data on all patients undergoing non-contrast cranial CT following blunt traumatic head injury from April 2006 to December 2015, at four emergency departments comprising community and university sites, as well as urban, suburban and rural settings in California (Antelope Valley Hospital, San Francisco General Hospital, UCLA Ronald Reagan Medical Center, UCSF Fresno Community Regional Medical Center). We classified each patient into one of three injury patterns: Type I-notable traumatic injuries primarily above the tentorium, with minimal posterior fossa involvement; Type II-notable traumatic injuries both above and within the posterior fossa; and Type III-notable traumatic injuries primarily within the posterior fossa. We extracted demographic data for each patient as well as physician assessments of the NEXUS head CT and Canadian Head CT rule clinical criteria, mechanisms of injury, patient outcomes, and the location and types of intracranial injuries sustained.

Findings

Of 11,770 patients in the database, 184 (1.6%) had posterior fossa injuries on CT imaging. Mean age was 55.4 years (standard deviation 22.5 years, range 2-96 years); 131 (71.2%) were males. We identified 63 patients with Type I injuries, 87 with Type II injuries, and 34 Type III injuries. The most common mechanisms of injury were falls (41%), pedestrian vs automobile (15%), and motor vehicle collisions (13%). On presentation most patients had altered mental status (72%), abnormal behavior (53%), or a neurologic deficit (55%). The majority of individuals, 151 (82%), had clinically important injuries and 111 (60%) required neurosurgical intervention. The dispositions for the subjects included 52 deaths (28%), 49 (27%) patients discharged home, and 48 (26%) discharged to rehabilitation facilities. When compared to individuals with Type I and Type II injuries, patients with Type III injuries had lower mortality (6% vs 30% and 35%) and higher percentage of patients discharged home (60% vs 19% and 21%).

Interpretation

Patients with Type I and II injury patterns (those that involve both the posterior fossa and supratentorium) experienced high mortality and disability. Patients with Type III injuries (isolated posterior fossa) had a better prognosis.

Funding

None.

Exploring Rare Traumatic Injuries: A Miniseries of 4 Cases Discussing Epidural Hematomas Bridging the Infratentorial and Supratentorial Regions

Supratentorial-infratentorial epidural hematomas (SIEH) are a rare occurrence following traumatic head injuries, representing only 2% of traumatic epidural hematomas. Given the unique anatomical characteristics of the infratentorial region, mainly its small size, surgical intervention is commonly undertaken to alleviate the pressure on the posterior fossa components. Consequently, there is ongoing debate surrounding the optimal surgical approaches.In this report, we present four cases of SIEH that were treated surgically. Furthermore, we conduct a comprehensive review of existing literature, encompassing clinical, radiological, and therapeutic aspects associated with this condition.SIEH are uncommon post-traumatic lesions that require urgent and individualized management on a case-by-case basis, as guided by multiplanar cerebral computed tomography scan findings. Preoperative planning is essential; however, intraoperative exploration and identification of transverse sinus and torcula lesions are crucial for optimal patient care. The surgical approach may be modified intraoperatively based on the nature and extent of these lesions. In all cases, prompt hematoma evacuation and meticulous hemostasis are the two primary objectives of this surgery.

Axial Convex-Shaped Hematoma was Associated with Poor Curative Effect of Surgical Treatment for Traumatic Posterior Fossa Epidural Hematoma in Children

BACKGROUND

Posterior fossa epidural hematoma (PFEDH) is rare which accounts for just 4-12.9% of all EDH cases. Since its frequently subtle and nonspecific clinical presentation, CT scan has great importance for early diagnosis and treatment of PFEDH. However, indications for surgery depending on the findings of CT image are still controversial.

METHODS

We retrospectively analyzed 40 pediatric cases of PFEDH. Their baseline characteristic, clinical presentation, imaging findings and outcomes were collected and analyzed. The ellipsoid volume equation X × Y × Z/2 was used to measure the hematoma volume. The Glasgow Outcome Scale (GOS) was used to assess the neurologic functional outcome.

RESULTS

A total of 40 pediatric PFEH patients were included with 8 patients having poor outcome and 32 patients having a relatively good prognosis. GCS score showed a significant difference between good and poor outcome groups (p < 0.001). Y value on CT image was significantly bigger in poor outcome group than good outcome group (p < 0.01). Similar results were got in X/Z value (p < 0.05) and Y/Z value (p < 0.01) which reflected the shape of hematoma. A predictive model with Y + X/Z showed the largest area under the ROC curve with a sensitivity of 75.0% and specificity of 93.7%.

CONCLUSIONS

GCS score at admission was closely related to the prognosis of the pediatric patients with PFEDH. The morphometry of PFEDH has a crucial role in judging the prognosis. Axial convex-shaped hematoma was associated with poor curative effect of surgical treatment.

Head Trauma Associated with Supra- and Infratentorial Epidural Hematoma: Diagnostic and Surgical Considerations

BACKGROUND

Supra- and infratentorial epidural hematoma (SIEDH) is a rare type of intracranial epidural hematoma. Due to the potential of vigorous hemorrhage from the injured transverse sinus (TS), it poses a challenge for neurosurgeons to evacuate the SIEDH.

METHODS

The medical records and radiographic studies were retrospectively reviewed to investigate the clinical and radiographic characteristics, clinical course, surgical findings and outcome in 34 patients with head trauma associated with SIEDH.

RESULTS

Patients treated surgically had a lower Glasgow Coma Scale score than those treated conservatively (P = 0.005). The surgical group had statistically larger thickness and volume of the SIEDH than those in the conservative group (P < 0.0001 and P < 0.0001, respectively). Six patients experienced significant intraoperative blood loss, and copious bleeding from the injured TS was noted in 5 (83.3%) of these patients. Five (50%) of 10 patients undergoing simple craniotomy experienced significant blood loss. However, only 1 patient (11.1%) undergoing strip craniotomy experienced significant blood loss, but no intraoperative shock. All patients experiencing massive blood loss and intraoperative shock underwent simple craniotomy. There was no statistical difference in the outcome between the conservative and surgical groups.

CONCLUSIONS

When operating on SIEDH, the possibility of vigorous bleeding from the injured TS and intraoperative massive bleeding should be kept in mind. Strip craniotomy that allows hitching the stripped dura to the bone strip overlying the TS may be a better method for the evacuation of SIEDH.

Management of traumatic posterior fossa epidural hematomas in pediatrics: our experience and review of the literature

BACKGROUND AND AIMS

Conservative management of posterior fossa epidural hematoma in the pediatric age group has been increasingly considered in the last decade with good clinical outcomes and comparable results to surgical intervention in carefully selected patients. The purpose of this study is to evaluate the outcome of observation in the management of pediatric patients with posterior fossa epidural hematoma (PFEDH) in our tertiary hospital and present a literature review on PFEDH pediatric patients.

METHODS

We conducted a retrospective observational study at King Abdullah University Hospital (KAUH), a tertiary hospital in North Jordan. All pediatric patients (≤ 18 years) who were admitted with a diagnosis of PFEDH from January 2010 to December 2020 were included. Demographic data, trauma type, clinical signs and symptoms on admission, CT findings, treatment type, and outcomes were collected and assessed. The outcome was measured using the Glasgow outcome scale (GOS) on discharge from the hospital.

RESULTS

A total of 16 patients were identified and included in this study. Nine patients were managed conservatively and 7 surgically. The mean age was 7.7 ± 6 years ranging from 1 to 18 years. Falls were the most common cause of injury. Vomiting was the most frequent presenting symptom. Except for 1 patient, 14 patients had good outcomes with a GOS of 5. One case of mortality was seen in our series.

CONCLUSION

Posterior fossa epidural hematoma is a rare clinical condition among the pediatric age group. Early and consecutive CT scans must be obtained for all suspected cases. Successful conservative management can be achieved depending on multiple factors such as hematoma thickness or volume, neurological status on admission, and other radiological findings as shown in our study. The overall prognosis was good in our patients.

Traumatic Posterior Fossa Epidural Hematomas in Children : Experience with 48 Cases and a Review of the Literature

OBJECTIVE

Epidural haematoma (EDH) most commonly occurs in the supratentorial area, particularly in the temporal region, of the brain. Posterior fossa epidural haematoma (PFEDH) is less frequently observed, accounting for only 1.2% to 12.9% of all EDH cases. Because of the non-specific symptoms and the potential for rapid and fatal deterioration in children, an early computed tomography (CT) scanning is necessary for all suspicious cases. The aim of the present study was to share the experience of 48 cases and review the literature concerning PFEDH.

METHODS

A retrospective analysis was conducted for 48 paediatric cases diagnosed with PFEDH and admitted to Yuying Children's Hospital of Wenzhou Medical University from January 2010 to August 2015. The clinical features and outcomes were analyzed and compared with previous literature.

RESULTS

Seventeen patients were surgically treated in this series and 31 patients received non-operative treatment. The outcomes were good in 46 patients, evaluated using the Glasgow outcome score (GOS), while mild disability was observed in one patient, and only one case showed severe disability. There were no cases of mortality in this series.

CONCLUSION

Posterior fossa epidural haematoma is relatively rare compared with supratentorial epidural haematoma. Early and serial CT scans should be performed for all suspicious cases. The criteria for the surgical treatment of paediatric patients with PFEDH were concluded. The overall prognosis was excellent in paediatric patients.

Traumatic Posterior Fossa Extradural Hematoma: Experience at Level I Trauma Center

INTRODUCTION

Posterior fossa extradural hematoma (PFEDH) is rare among the traumatic brain injury and represent about 4-7% cases of all EDHs. This rare condition is rapidly fatal unless identified and intervened timely. Because of limited space in posterior fossa, comparatively small volume can cause clinical deterioration. Early diagnosis by cranial computed tomography and emergent evacuation is vital for a good outcome.

MATERIALS AND METHODS

This study was conducted at Level I trauma center at All India Institute of Medical Sciences, New Delhi, India. Hospital medical records were reviewed from September 2007 to June 2015. There were 856 cases of acute EDHs and of these 69 cases had PFEDHs. Records of patients with PFEDHs were reviewed for the mode of injury, Glasgow Coma Scale (GCS) at admission, imaging, type of intervention, outcome, and follow-up. GCS was assessed at 6 months and 12 months follow-up. Pertinent literature is reviewed.

RESULTS

Of these 69 patients, 51 were males and 18 females. The mean age of patients was 28.6 years (range 4-43 years). Forty-three patients had GCS 15 at admission, and only 4 of them had admission GCS <8. Mean EDH volume was 29.2 ml. Sixty-six patients were operated, three managed conservatively. Sixty-seven patients were discharged, of which, 56 (81.1%) had GCS 15. Two patients died. Most common associated injuries were long bone fractures (18, 26.1%) followed by blunt injury thorax (11, 15.9%). Mean follow-up duration was 69.2 months (range 6-94 months). At 6 months follow-up, 61 (88.4%) patients had good recovery (Glasgow Outcome Score [GOS] 5) and at 12 months, 62 (89.8%) had GOS 5.

CONCLUSION

PFEDH are rare. They are usually associated with occipital bone fractures and may also have a supratentorial hematoma. It may be rapidly fatal due to the expansion of hematoma and compromise of the posterior cranial fossa space leading to brainstem compression, tonsillar herniation, and/or obstructive hydrocephalus. Early diagnosis and emergent evacuation lead to good outcome.

Imaging Evaluation of Acute Traumatic Brain Injury

Traumatic brain injury (TBI) is a major cause of morbidity and mortality worldwide. Imaging plays an important role in the evaluation, diagnosis, and triage of patients with TBI. Recent studies suggest that it also helps predict patient outcomes. TBI consists of multiple pathoanatomic entities. This article reviews the current state of TBI imaging including its indications, benefits and limitations of the modalities, imaging protocols, and imaging findings for each of these pathoanatomic entities. Also briefly surveyed are advanced imaging techniques, which include several promising areas of TBI research.

Traumatic Pediatric Posterior Fossa Extradural Hematomas: A Tertiary-Care Trauma Center Experience from India

INTRODUCTION

Traumatic posterior fossa extradural hematomas (PFEDH) are rare lesions constituting <10% of all extradural hematomas. Reliance on clinical findings alone is not recommended as these are nonspecific; for all suspicious cases, it is advisable to conduct a CT scan. Only a handful of pediatric studies have been reported analyzing the outcome of such lesions. The aim of our study was to analyze outcomes for children with PFEDH managed at our apex trauma center.

MATERIALS AND METHODS

We conducted a retrospective analysis of pediatric patients (≤18 years) admitted with a diagnosis of traumatic PFEDH from January 2008 to February 2014.

RESULTS

Of 22 patients, 16 were managed surgically (group 1) and 6 conservatively (group 2); 1 failed conservative treatment (due to an increased EDH volume). Mean age was 11.7 years (range 2-18 years). Falls were the most common cause of injury. Vomiting and loss of consciousness were the most frequent presenting features. There were 18 mild, 2 moderate and 2 severe head injuries. The mean volume of EDH was 37.1 ml (range 18-100 ml) and 10.3 ml (8-16 ml) in the operative and conservative subgroups, respectively. Occipital bone fracture was seen in 16 cases with supratentorial extension in 11. Four complications were noted in 3 cases. Mean follow-up duration was 25.1 months (range 3-34 months). Except for 1 patient, all had excellent outcomes. There was no mortality.

CONCLUSIONS

Traumatic pediatric PFEDHs are rare. Both the clinical status of the patient and the volume of the hematoma need to be assessed before deciding on surgery. Most cases have associated occipital bone fractures and around half have supratentorial extension; these need to be carefully assessed preoperatively. Torrential venous bleeding can be a major problem due to rupture of the adjacent sinuses. Timely intervention is crucial for achieving good outcome, keeping in view a low threshold for surgical evacuation. Although not innovative, this second-largest case series provides additional data and contributes to the existing literature on such lesions in pediatric patients.

Posterior fossa epidural hematomas in children: clinical experience with 40 cases

OBJECT

Traumatic posterior fossa epidural hematoma (PFEDH) is rare, but among children it may have a slightly higher incidence. With the widespread use of CT scanning, the diagnosis of PFEDH can be established more accurately, leading to an increased incidence of the lesion and possibly to a better patient prognosis. This study presents 40 pediatric cases with PFEDH.

METHODS

The authors assessed the type of trauma, clinical findings on admission, Glasgow Coma Scale scores, CT findings (thickness of the hematoma, bone fracture, compression of the fourth ventricle, and ventricle enlargement), type of treatment, clinical course, and prognosis. Early postoperative CT scans (within the first 6 hours) were obtained and reviewed in all surgical cases.

RESULTS

Twenty-nine patients underwent surgery and 11 patients received conservative therapy and close follow-up. All patients fared well, and there was no surgical mortality or morbidity.

CONCLUSIONS

Based on the data in this large series, the authors conclude that PFEDH in children can be treated in experienced centers with excellent outcome, and there is no need to avoid surgery when it is indicated.

Trephine craniotomy for evacuation of posterior fossa extradural hematoma

Extradural hematomas (EDH) commonly occur in the supratentorial region where these are evacuated by trephine or craniotomy. Posterior fossa EDH (PFEDH) account for 4% to 12.9% of all cranial EDH and the standard method for evacuation of PFEDH involves a suboccipital craniectomy. Use of a trephine craniotomy for evacuation of PFEDH has not yet been described. This is the first report describing our experience in 8 patients with PFEDH where a sub occipital trephine craniotomy was used for evacuation of PFEDH. Eight patients with PFEDH were operated at our institution using a trephine for making a sub occipital craniotomy. Park bench position was used in all patients. The procedure was safely and expeditiously completed with no significant peri-operative complications related to the procedure. Operative time was comparatively shorter than for traditionally described procedures. Replacing the bone flap also avoids any scope for the possibility of occurrence of the sinking skin flap syndrome. We think that using a trephine for making a sub occipital craniotomy for evacuation of PFEDH is a feasible and safe option. There is no added risk of venous sinus injury. Replacing the bone flap helps to restore the normal anatomy. Use of central and peripheral dural hitch sutures in patients of traumatic PFEDH is feasible and avoids any possible reaccumulation of hematoma.

[Epidural hematomas of the posterior fossa]

BACKGROUND

Posterior fossa epidural hematomas represent 7-14% of all traumatic intracranial epidural hematomas. They are most frequently encountered posttraumatic mass lesions in the posterior fossa. The aim of this study was to identify clinical features that could lead to the early diagnosis of posterior fossa epidural hematoma.

METHODS

Between 1980 and 2002, 28 patients with epidural hematoma of the posterior fossa were operated on at the Institute for Neurosurgery, Belgrade. Clinical course, neuroradiological investigations, and the results of surgical treatment of the patients with posterior fossa epidural hematomas were analyzed retrospectively.

RESULTS

Almost two thirds of patients were younger than 16 years of age. In 20 cases injury was caused by a fall, in 6 cases by a traffic accident, and in 2 by the assault. Clinical course was subacute or chronic in two thirds of the patients. On the admission Glasgow Coma Scale was 7 or less in 9 injured, 8-14 in 14 injured, and 15 in 5 injured patients. Linear fracture of the occipital bone was radiographically evident in 19 patients, but was intraoperatively encountered in all the patients except for a 4-year old child. In 25 patients the diagnosis was established by computer assisted tomography (CAT) and in 3 by vertebral angiography. All the patients were operated on via suboccipital craniotomy. Four injured patients who were preoperatively comatose were with lethal outcome. Postoperatively, 24 patients were with sufficient neurologic recovery.

CONCLUSION

Posterior fossa epidural hematoma should be suspected in cases of occipital injury, consciousness disturbances, and occipital bone fracture. In such cases urgent CAT-scan is recommended. Early recognition, early diagnosis, and prompt treatment are crucial for good neurological recovery after surgery.

Epidural hematomas of the posterior cranial fossa

Object

The authors present their experience in the management of posterior fossa epidural hematoma (PFEDH), which involved an aggressive diagnostic approach with the extensive use of head computerized tomography (CT) scanning.

Methods

The authors treated 43 cases of PFEDH in one of the largest health centers in Brazil. Diagnosis was established in all patients with the aid of CT scanning because the clinical manifestations were frequently nonspecific. Cases were stratified by clinical course, Glasgow Coma Scale score, and their radiological status. Based on clinical and radiological parameters the patients underwent surgical or conservative management.

Conclusions

Compared with outcomes reported in the available literature, good outcome was found in this series. This is primarily due to the broad use of CT scanning for diagnostic and observational purposes, which, in the authors' opinion, led to early diagnosis and prompt treatment.

Posterior fossa extradural hematoma

OBJECTIVE

To review the clinical profile, radiology and treatment of Pediatric posterior fossa extradural hematoma (PPFEDH) and evaluate the outcome.

METHODS

Posterior fossa extradural hematoma (PFEDH) is an uncommon trauma sequel and in pediatric age group is still rare. This article discusses 18 cases of PPFEDH seen over a period of 8 years and review the pertinent medical literature. Only a few studies discuss PPFEDH and in most of them outcome has been good. Trauma has been subtle and fracture of occipital bone is seen in majority of cases. Treatment has been operative in majority of the cases.

RESULTS

Most of the patients were diagnosed only on high index of suspicion with a history of trauma on the occipit, fracture of the occipital bone and persistent symptoms suggestive of increasing intracranial pressure and posterior fossa space occupying lesion. CT scanning was done liberally to confirm the suspicion and the patients with hematoma were treated aggressively by surgical evacuation with good recovery in most of them.

CONCLUSION

Authors suggest an aggressive approach in the event of PPFEDH. However some patients can be managed conservatively but they should be closely observed for clinical manifestation and CT scan routinely to evaluate the progress of hematoma radiologically. A strict criterion should be followed in choosing such patients for conservative treatment as highlighted in the study.

Extradural hematoma of the posterior cranial fossa

Fourteen cases of an extradural hematoma of the posterior fossa (EDHPF), are presented and the clinical and radiological finds are described. The onset of symptoms was acute in 10 patients and subacute in the other 4. Hematomas occurred in the younger age groups with a clear male predominance. Nine cases had suffered a blow to the head. A fracture of the occipital bone was seen in 86% of the patients. The bleeder could be identified in 10 cases, and in 6 of these the source was a bleeding transverse sinus. The overall mortality was 14.2%, but only patients with an acute course died (20%). All subacute cases survived. This study revealed that the most important factors influencing mortality were late diagnosis and late treatment. Coexisting intracranial lesions had no influence on mortality. According to the literature, there has been a certain decrease in mortality in the acute and subacute course patients since the introduction of computed tomography (CT) scanning. Emphasis is placed on the importance of occipital soft-tissue swelling and occipital fracture as clues to the possible presence of extradural hematomas, and of using the CT in all such patients even if no clinical symptoms are present.

The CT criteria for conservative treatment--but under close clinical observation--of posterior fossa epidural haematomas

In order to assess whether the indications for conservative treatment of supratentorial epidural haematomas are applicable also to posterior fossa epidural haematomas (PFEDH), the author reviewed the records of 25 patients. With a PFEDH volume of no more than 10 ml, a thickness of no more than 15 mm, a midline shift of no more than 5 mm, and in the absence of a significant intracranial haematoma elsewhere on computed tomography (CT) scans, the patients undergoing conservative treatment achieved the same excellent outcome as those undergoing early surgery. These CT criteria for conservative treatment of PFEDHs are similar to those of supratentorial epidural haematomas except the volume factor, namely, 10 ml in the former against 30 ml in the latter. That means a PFEDH of 10 ml or larger in the small posterior fossa may produce the same degree of midline shift and compression, and be as dangerous as an epidural haematoma of 30 ml or larger in the more capacious supratentorial compartment. But also for epidural haematomas of the posterior fossa, which initially are smaller than 10 ml, the general rule remains valid that they should be under close clinical supervision.