Traumatic Subdural Hygromas: Proposed Pathogenesis Based Classification

A Subdural Hygroma Necessitating a Subdural-Peritoneal Shunt in a Pediatric Patient Following Total Cranial Vault Remodeling Surgery

Sagittal synostosis is a common non-syndromic synostosis treated with open or endoscopic cranial vault remodeling. Early intervention is recommended to avoid restricted brain growth, increased intracranial pressure, and resultant developmental delay. Common complications such as failure or reconstruction, cerebrospinal fluid leak, blood loss, and stroke are well-reported in the literature. Here, we present a rare case of the development of a subdural hygroma following cranial vault remodeling in a seven-month-old male, necessitating the insertion of a subdural-peritoneal shunt.

Subdural fluid accumulation caused by ventriculoperitoneal shunt underdrainage: A rare and paradoxical complication

Background:

Subdural fluid collection in patients with internal cerebrospinal fluid (CSF) shunts has generally been linked to overdrainage and more rarely to pus accumulation. The authors present a previously unrecognized condition leading to extra-axial CSF accumulation: shunt underdrainage. Treatment of coexisting subdural fluid collection and hydrocephalus, disorders that have previously only been reported concurrently following head trauma or subarachnoid hemorrhage, is controversial. In addition, we intend to provide insight into the physiopathology of abnormal CSF accumulation within both the subdural space and ventricles simultaneously.

Case Description:

A 42-year-old female with a history of hypothalamic glioma and obstructive hydrocephalus during childhood presented with headache, vomiting, and gait disturbance. Following the insertion of her first ventriculoperitoneal shunt (VPS) by the age of 8, she underwent several surgeries due to shunt failure, all of them associating ventriculomegaly. Ventricles remained notably enlarged following insertion of her most recent VPS, and the computed tomography scan performed 2 months later at her admission showed a large subdural collection. Afterward, a malpositioned distal catheter causing shunt blockage was confirmed. Both, the subdural accumulation and hydrocephalus, were resolved following adequate placement of the peritoneal catheter.

Conclusion:

This case demonstrates that subdural fluid accumulations may occur following VPS underdrainage with hydrocephalus. Development of such extra-axial collection was probably caused by pressure related to CSF spillage from the ventricles into the subdural space. Our case also supports that a mass-effect subdural accumulation with hydrocephalus can be satisfactorily treated with adequate VPS alone, without directly treating the subdural collection.

Traumatic Brain Injury: Imaging Patterns and Complications

While the diagnosis of traumatic brain injury (TBI) is a clinical decision, neuroimaging remains vital for guiding management on the basis of identification of intracranial pathologic conditions. CT is the mainstay of imaging of acute TBI for both initial triage and follow-up, as it is fast and accurate in detecting both primary and secondary injuries that require neurosurgical intervention. MRI is more sensitive for the detection of certain intracranial injuries (eg, axonal injuries) and blood products 24-48 hours after injury, but it has limitations (eg, speed, accessibility, sensitivity to motion, and cost). The evidence primarily supports the use of MRI when CT findings are normal and there are persistent unexplained neurologic findings or at subacute and chronic periods. Radiologists should understand the role and optimal imaging modality to use, in addition to patterns of primary brain injury and their influence on the risk of developing secondary brain injuries related to herniation. ^©RSNA, 2019 See discussion on this article by Mathur and Nicolaou.

Incidence and risk factors of early postoperative complications in patients after decompressive craniectomy: a 5-year experience

PURPOSE

Decompressive craniectomy is an effective measure to reduce a pathologically elevated intracranial pressure. Patients' survival and life quality following this surgery have been a subject of several studies and significantly differ according to the primary diagnosis. Since this operation is often associated with a wide spectrum of possibly serious complications, we aimed to describe their incidence and possible associated risk factors.

METHODS

We evaluated 118 patients who underwent decompressive craniectomy at our clinic during years 2013-2017. The indications included traumatic brain injuries, ischaemic or haemorrhagic strokes and postoperative complications of planned neurosurgical procedures. Subsequently, we assessed the incidence of early postoperative complications (occurring during the first 3 postoperative weeks). The results were statistically analysed with relation to a wide selection of possible risk factors.

RESULTS

At least one early surgical postoperative complication occurred in 87 (73.73%) patients, the most frequent being a development of an extraaxial fluid collection in 41 (34.75%) patients. We were able to identify risk factors linked with extraaxial fluid collections, subcutaneous and extradural haematomas, postoperative seizures and meningitis. An overall need for reoperation was 13.56%. Neither the duration of the surgery nor the qualification of the operating surgeon had any effect on the complications' occurrence.

CONCLUSIONS

Decompressive craniectomy is associated with numerous early postoperative complications with a various degree of severity. Most cases of complications can, however, be managed in a conservative way. The risk factors linked with postoperative complications should be taken into account during the indication process in each individual patient.

Risk factors for the development of chronic subdural hematoma in patients with subdural hygroma

OBJECTIVE

Patients with subdural hygroma (SDG) are at increased risk of developing chronic subdural hematoma (CSDH). However, the factors that increase the risk of conversion are not fully understood. This study was to assess the risk factors of SDG conversion to CSDH.

METHODS

We reviewed the literature and retrospectively studied a series of cases in which CSDH was preceded by SDG to understand the natural history. We reviewed 45 cases of SDG from our hospital between 2015 and 2018. The cases were divided into two groups according to whether SDG converted into CSDH. Data were collected clinical presentation, imaging findings et al. Univariate and multivariate logistic regression analyses were performed to identify factors associated with SDG conversion.

RESULTS

Univariate analysis showed that the SDG thickness (p = .009), SDG location (p = .026), and bilateral SDG (p = .042) were significantly associated with CSDH development. Multivariate analysis revealed that SDG thickness (odds ratio, 1.6; 95% confidence interval, 1.111-2.324; p = .012) and bilateral SDG (odds ratio, 27.6; 95% confidence interval 2.889-263.548; p = .004) were independent risk factors for SDG development. Receiver operating characteristic curve analysis revealed that SDG thickness was a significant variable for predicting SDG development. A thickness >11.37 mm was an appropriate cutoff value, and the possibility of SDG conversion had a sensitivity 50.0% and specificity of 87.0%.

CONCLUSIONS

Bilateral SDG and SDG thickness were independent risk factors for SDG progression into CSDH. An SDG thickness >11.37 mm had a high risk of SDG conversion.

High-degree centrum semiovale-perivascular spaces are associated with development of subdural fluid in mild traumatic brain injury

Background

Severe centrum semiovale perivascular spaces (CSO-PVSs) are associated with the onset of brain atrophy and dementia. This study explored the relationship between severity of CSO-PVS and development of subdural fluid (SDF) in patients with mild traumatic brain injury (TBI), with the aim of investigating independent radiological risk factors for development of SDF.

Methods

The study cohort comprised 222 patients with a mean age of 51 years (64.0% men) who presented with mild TBI from January 2013 to November 2016. In this study, mild TBI was defined as a Glasgow Coma Scale (GCS) of ≥ 13, Post-Traumatic Amnesia (PTA) of <1 day, and Loss of Consciousness (LOC) of <30 minutes. The severity of CSO-PVS was categorized as low or high-degree.

Results

Among the 222 enrolled patients, 38 (17.1%) and 90 (40.5%) had high-degree PVS in the basal ganglia (BG) and centrum semiovale, respectively. Compared with patients who did not develop SDF, the mean age of patients who developed SDF was significantly higher (47.41 years versus 60.33 years, P < 0.0001). The incidence of de novo SDF was significantly higher in men than in women (77.8% versus 59.5%, P = 0.0151). Patients who showed SDF on brain computed tomography at admission more frequently developed de novo SDF (68.5% versus 38.1%, P < 0.0001). In multivariate logistic regression analysis of risk factors, high-degree CSO-PVS, male sex, initial SDF on admission, and old age were independently associated with development of de novo SDF after mild TBI. In Cox proportional hazards models of risk factors for SDF-development free survival rate, high-degree CSO-PVS, old age, and initial subdural hemorrhage showed statistically significant differences.

Conclusions

Our study might help neurosurgeons determine the frequency of brain CT or the duration of follow-up for patients who present with mild TBI with high-degree CSO-PVS.

Subdural haematoma mimics

A subdural haematoma (SDH) is a frequently encountered pathology seen on an emergency room computed tomography (CT) head scan. An extra-axial crescentic density along the convexity of the brain or within the interhemispheric fissure is generally thought to represent a SDH; however, SDH mimics are known to occur in nature, and can be broadly classified under the subcategories of normal anatomy, artefacts, tumour, inflammation, infection, ischaemia, trauma, and iatrogenic. Understanding the typical characteristics of a SDH, knowledge of normal anatomy, close inspection of the morphology of the subdural process, changes to the adjacent structures, and rigorous attention to clinical details may reveal subtle clues that distinguish a true SDH from a mimic. This is crucial in appropriately directing clinical management. This review amalgamates most of the rare subdural processes that have been reported to mimic SDH, and discusses the imaging and clinical features that help to differentiate between them. This topic is highly valuable for radiology trainees, general radiologists, and emergency room physicians, and may serve as a refresher for the practising neuroradiologist.

Management of subdural effusion and hydrocephalus following decompressive craniectomy for posttraumatic cerebral infarction in a patient with traumatic brain injury: a case report

Background

Subdural effusion with hydrocephalus (SDEH) is a rare complication of traumatic brain injury, especially following decompressive craniectomy (DC) for posttraumatic cerebral infarction. The diagnosis and treatment are still difficult and controversial for neurosurgeons.

Case presentation

A 45-year-old man developed traumatic cerebral infarction after traumatic brain injury and underwent DC because of the mass effect of cerebral infarction. Unfortunately, the complications of traumatic subdural effusion (SDE) and hydrocephalus occurred in succession following DC. Burr-hole drainage and subdural peritoneal shunt were performed in sequence because of the mass effect of SDE, which only temporarily improved the symptoms of the patient. Cranioplasty and ventriculoperitoneal shunt were performed ultimately, after which SDE disappeared completely. However, the patient remains severely disabled, with a Glasgow Outcome Scale of 3.

Conclusions

It is important for neurosurgeons to consider the presence of accompanying hydrocephalus when treating patients with SDE. Once the diagnosis of SDEH is established and the SDE has no mass effect, timely ventriculoperitoneal shunt may be needed to avoid multiple surgical procedures, which is a safe and effective surgical method to treat SDEH.

History of Chronic Subdural Hematoma

Trephination or trepanation is an intentional surgical procedure performed from the Stone Age. It looks like escaping a black evil from the head. This technique is still used for treatment of chronic subdural hematoma (SDH). Now, we know the origin, pathogenesis and natural history of this lesion. The author try to explore the history of trephination and modern discovery of chronic SDH. The author performed a detailed electronic search of PubMed. By the key word of chronic SDH, 2,593 articles were found without language restriction in May 2015. The author reviewed the fact and way, discovering the present knowledge on the chronic SDH. The first authentic report of chronic SDH was that of Wepfer in 1657. Chronic SDH was regarded as a stroke in 17th century. It was changed as an inflammatory disease in 19th century by Virchow, and became a traumatic lesion in 20th century. However, trauma is not necessary in many cases of chronic SDHs. The more important prerequisite is sufficient potential subdural space, degeneration of the brain. Modifying Virchow's description, chronic SDH is sometimes traumatic, but most often caused by severe degeneration of the brain. From Wepfer's first description, nearly 350 years passed to explore the origin, pathogenesis, and fate of chronic SDH. The nature of the black evil in the head of the Stone Age is uncovering by many authors riding the giant's shoulder. Chronic SDH should be categorized as a degenerative lesion instead of a traumatic lesion.

Surgical management of the patients with chronic subdural haematoma and contralateral subdural effusion: Operation or no-operation?

OBJECTIVE

Patients with chronic subdural haematoma and contralateral subdural effusion are rare after head injury. Surgery might reduce clinical progression of subdural effusion, but is not used routinely. This study aimed to investigate the effect of surgery on subdural effusion and clinical outcome.

METHODS

A retrospective study was performed, comparing operation and non-operation in the patients with chronic subdural haematoma and contralateral subdural effusion, in a series of 47 patients divided into two groups. The operation group of 21 patients underwent bilateral surgery. The non-operation group of 26 patients underwent surgery on the side with chronic subdural haematoma. Neurological status was assessed by the Glasgow Coma score and Modified Rankin Scale score on admission and at follow-up. All cases underwent pre- and post-operative computed tomography scans.

RESULTS

Pre-operative clinical and radiological data were similar in the two groups. The rate of subdural effusion progression was significantly lower in the operation group than in the non-operation group (p < 0.05). Thirteen cases (50%) in the non-operation group and three cases (14.3%) in the operation group had progression of subdural effusion to chronic subdural haematoma (p < 0.05). Chronic subdural haematoma recurrence rate, mortality and neurological recovery were similar, with no significant difference between groups.

CONCLUSIONS

The patients benefitted from surgery for subdural effusion when they had chronic subdural haematoma and contralateral subdural effusion.

Subdural hygromas in abusive head trauma: pathogenesis, diagnosis, and forensic implications

Are subdural hygromas the result of abusive head trauma? CT and MR imaging represent important tools for the diagnosis of abusive head trauma in living infants. In addition, in-depth understanding of the pathogenesis of subdural hygromas is increasingly required by neuroradiologists, pediatricians, and forensic physicians. Therefore, the current knowledge on subdural hygromas is summarized and forensic conclusions are drawn. The most important diagnostic pitfalls, benign enlargement of the subarachnoid space, and chronic subdural hematoma, are discussed in detail. Illustrative cases from forensic practice are presented. Literature analysis indicates that subdural hygromas can occur immediately or be delayed. If other infrequent reasons can be excluded, the presence of subdural hygromas strongly suggests a posttraumatic state and should prompt the physician to search for other signs of abuse. To differentiate subdural hygromas from other pathologies, additional MR imaging of the infant's head is indispensable after initial CT scan.

Intracranial subdural hygroma after Le Fort I osteotomy

Various intra- and postoperative complications have been well-documented after Le Fort I osteotomies; however, an intracranial subdural hygroma has not yet been reported in oral and maxillofacial studies. We report a unique case of an intracranial subdural hygroma requiring neurosurgical intervention after Le Fort I advancement.

Acute enlargement of subdural hygroma due to subdural hemorrhage in a victim of child abuse

An 11-month-old female baby was found dead by her mother. Cranial postmortem CT prior to the forensic autopsy showed dilatation of bilateral extra-axial spaces and ventricles. The autopsy revealed a new linear fracture of the left parietal bone and occipital bone, and a healed linear fracture of the right parietal bone and occipital bone like a mirror image of the left one as well. Intracranially, 230ml of subdural fluid were collected, which was mixed with blood. There was a fresh hemorrhage around a bridging vein of the left parietal lobe and the dura mater. Moreover, the outer side of the cerebrum and the inner side of the dura mater were covered by a thin membrane, which mater might have been previously formed because of being positive for Fe-staining and anti-CD68 antibody. A subdural hematoma might have been developed when the right side of the skull was previously fractured, which was transformed into a subdural hygroma. Subsequently, it is likely that, after the left side fracture of the skull occurred, the subdural hygroma rapidly enlarged due to hemorrhaging from the bridging vein, which resulted in intracranial hypertension, because microbleeding was detected in the brain stem. Accordingly, we diagnosed the cause and manner of death as intracranial hypertension due to subdural hemorrhage in subdural hygroma, and homicide, including child abuse, respectively.

Natural course of initially non-operated cases of acute subdural hematoma : the risk factors of hematoma progression

Objective

The objectives of the present study were to characterize the natural course of initially non-operated traumatic acute subdural hematoma (ASDH) and to identify the risk factors of hematoma progression.

Methods

Retrospective analysis was performed using sequential computed tomography (CT) images maintained in a prospective observational database containing 177 ASDH cases treated from 2005 to 2011. Patients were allocated to four groups as followings; 136 (76.8%) patients to the spontaneous resolution group, 12 (6.8%) who underwent operation between 4 hours and 7 days to the rapid worsening group (RWG), 24 (13.6%) who experienced an increase of hematoma and that underwent operation between 7 and 28 days to the subacute worsening group (SWG), and 5 (2.8%) who developed delayed aggravation requiring surgery from one month after onset to the delayed worsening group (DWG). Groups were compared with respect to various factors.

Results

No significant intergroup difference was found with respect to age, mechanism of injury, or initial Glasgow Coma Scale. The presence of combined cerebral contusion or subarachnoid hemorrhage was found to be a significant prognostic factor. Regarding CT findings, mixed density was common in the RWG and the SWG. Midline shifting, hematoma thickness, and numbers of CT slices containing hematoma were significant prognostic factors of the RWG and the SWG. Brain atrophy was more severe in the SWG and the DWG.

Conclusion

A large proportion of initially non-operated ASDHs worsen in the acute or subacute phase. Patients with risk factors should be monitored carefully for progression by repeat CT imaging.

The pathophysiology of brain swelling associated with subdural hemorrhage: the role of the trigeminovascular system

INTRODUCTION

This paper reviews the evidence in support of the hypothesis that the trigeminal system mediates brain swelling associated with subdural bleeding. The trigeminovascular system has been extensively studied in migraine; it may play an important but under-recognized role in the response to head trauma. Nerve fibers originating in trigeminal ganglion cells are the primary sensors of head trauma and, through their collateral innervation of the intracranial and dural blood vessels, are capable of inciting a cascade of vascular responses and brain swelling. The extensive trigeminal representation in the brainstem initiates and augments autonomic responses. Blood and tissue injury in the dura incite neurogenic inflammatory responses capable of sensitizing dural nerves and potentiating the response to trauma.

DISCUSSION

The trigeminal system may provide the anatomo-physiological link between small-volume, thin subdural bleeds and swelling of the underlying brain. This physiology may help to explain the poorly understood phenomena of "second-impact syndrome," the infant response to subdural bleeding (the "big black brain"), as well as post-traumatic subdural effusions. Considerable age-specific differences in the density of dural innervation exist; age-specific responses of this innervation may explain differences in the brain's response to trauma in the young. An understanding of this pathophysiology is crucial to the development of intervention and treatment of these conditions. Antagonists to specific neuropeptides of the trigeminal system modify brain swelling after trauma and should be further explored as potential therapy in brain trauma and subdural bleeding.

Treatment of patients with traumatic subdural effusion and concomitant hydrocephalus

Object

Traumatic subdural effusion (TSE) is a common sequela of traumatic brain injury. Surgical intervention is suggested only when TSE exerts mass effect. The authors have found that many patients with TSE exerting mass effect have concomitant hydrocephalus. Patient experiencing this occurrence were studied, and the pathogenesis of this phenomenon was discussed in the context of recent advances in the understanding of CSF circulation.

Methods

During a 2-year period, the authors' institution treated 14 patients with TSE who developed hydrocephalus, after 1 of the patients suffered subdural drainage and other 13 received subdural peritoneal shunt (SPSs). Thirteen of those who had SPSs received programmable ventriculoperitoneal shunts (VPSs) for the hydrocephalus. The clinical characteristics as well as the imaging and operative findings of these patients were reviewed.

Results

All patients with symptomatic TSE exerting mass effect received SPSs. All of these patients had a modified Frontal Horn Index of more than 0.33 at presentation, and high opening pressure on durotomy. Following a brief period (4–7 days) of clinical improvement, the condition of all patients deteriorated due to hydrocephalus. Programmable VPSs were inserted with the initial pressure set at approximately 8–10 cm H2O according to opening pressure at ventriculostomy. Shunt valve pressure was gradually decreased to 5–7 cm H2O, according to clinical and radiological follow-up.

Conclusions

Elevated modified Frontal Horn Index in patients with TSE is suggestive of concomitant hydrocephalus. The authors propose that tearing of the dura-arachnoid plane following trauma contributes to TSE and may also impede CSF circulation, causing hydrocephalus. Shunt pressure was adjusted to relative low pressure, indicating the old age of the patients and poor reexpansion of brain parenchyma after the mass effect. Subdural peritoneal shunts and VPSs are indicated in those patients with TSE exerting mass effect with concomitant hydrocephalus.

Risk factors associated with subdural hygroma after decompressive craniectomy in patients with traumatic brain injury : a comparative study

OBJECTIVE

Subdural hygroma (SDG) is a complication occurring after head trauma that may occur secondary to decompressive craniectomy (DC). However, the mechanism underlying SDG formation is not fully understood. Also, the relationship between the operative technique of DC or the decompressive effect and the occurrence and pathophysiology of SDG has not been clarified. Purpose of this study was to investigate the risk factors of SDG after DC in our series.

METHODS

From January 2004 to December 2008, DC was performed in 85 patients who suffered from traumatic brain injury. We retrospectively reviewed the clinical and radiological features. For comparative analysis, we divided the patients into 2 groups : one group with SDG after craniectomy (19 patients; 28.4% of the total sample), the other group without SDG (48 patients; 71.6%). The risk factors for developing SDG were then analyzed.

RESULTS

The mean Glasgow Outcome Scale (GOS) scores at discharge of the groups with and without SDG were 2.8 and 3.1, respectively (p<0.0001). Analysis of radiological factors showed that a midline shift in excess of 5 mm on CT scans was present in 19 patients (100%) in the group with SDG and in 32 patients (66.7%) in the group without SDG (p<0.05). An accompanying subarachnoid hemorrhage (SAH) was seen in 17 patients (89.5%) in the group with SDG and in 29 patients (60.4%) in the group without SDG (p<0.05). Delayed hydrocephalus accompanied these findings in 10 patients (52.6%) in the group with SDG, versus 5 patients (10.4%) in the group without SDG (p<0.05). On CT, compression of basal cisterns was observed in 14 members (73.7%) in the group with SDG and in 18 members of the group without SDG (37.5%) (p<0.007). Furthermore, tearing of the arachnoid membrane, as observed on CT, was more common in all patients in the group with SDG (100%) than in the group without SDG (31 patients; 64.6%) (p<0.05).

CONCLUSION

GOS showed statistically significant difference in the clinical risk factors for SDG between the group with SDG and the group without SDG. Analysis of radiological factors indicated that a midline shifting exceeding 5 mm, SAH, delayed hydrocephalus, compression of basal cisterns, and tearing of the arachnoid membrane were significantly more common in patients with SDG.

Normal pressure subdural hygroma with mass effect as a complication of decompressive craniectomy

BACKGROUND

Subdural posttraumatic collections are called usually Traumatic Subdural Hygroma (TSH). TSH is an accumulation of cerebrospinal fluid (CSF) in the subdural space after head injury. These collections have also been called Traumatic Subdural Effusion (TSE) or External Hydrocephalous (EHP) according to liquid composition, or image features. There is no agreement about the pathogenesis of these entities, how to define them or if they are even different phenomena at all.

CASE DESCRIPTION

We present a case of a complex posttraumatic subdural collection, the role of cranioplasty as definite solution and review the literature related to this complication.

CONCLUSION

Patients who undergo decompressive craniectomy (DC) have a risk of suffering a subdural collection of 21-50%. Few of these collections will become symptomatic and will need evacuation. When this happens, cranioplasty might be the definitive solution.