Extra-axial Collections Research Articles

Chronic subdural hematoma: What precisely are we treating?

Subdural hematoma (SDH) refers to the collection of blood between the dura matter and the arachnoid membrane. Advancements in imaging technology have enabled the categorization of SDH based on specific imaging characteristics, causative factors, and the onset of symptoms. Given that the prognosis of SDHs varies significantly and is contingent upon the size and chronicity of the hemorrhage, a comprehensive understanding of its subtypes may carry crucial treatment implications. For example, an acute SDH classically results from severe traumatic brain injury and appears as a homogenous, crescent-shaped hyperdense extra-axial collection. If not treated, over the course of 1-3 weeks, this hematoma will evolve into a sub-acute phenotype as a consequence of subdural effusion and demonstrate mixed-density hemorrhage on imaging. Chronic SDH (cSDH) becomes the end result of an untreated SDH, with neo-membranization and neo-angiogenesis from branches of the middle meningeal artery driving a mass-like growth pattern. This review article aims to elucidate the complex anatomical features of the end-stage cSDH, with a particular focus on reconceptualization of this entity based on its mass-like growth patterns, and how this is driving a shift towards endovascular treatment.

Rediscovering extra-axial collections on medical imaging: subdural lymphatic hygroma.

Rediscovering extra-axial collections on medical imaging: subdural lymphatic hygroma.

Isolated traumatic retroclival interdural hematoma causing craniocervical instability: A case report of pathology in a rare location and literature review

Introduction. Retroclival hematomas (RCH) are a rare entity primarily as a post-traumatic phenomenon in the pediatric population. We present a case of Retroclival interdural hematoma in a 12 y/o female with a previous record of craniocervical trauma. A RCH is identified initially by CT and easily overlooked. MRI cervical spine to evaluate the Tectorial membrane and other craniocervical ligaments integrity. Case report. A 12-year-old female presented with bilateral abducens nerve palsies and a Glasgow Coma Score (GCS) of 13 following a high-speed motor vehicle accident. Initial CT brain revealed an infra-tentorial extra-axial focal hyperdense collection (hemorrhage) along the retroclival region in the interdural space measuring approximately 9 × 29 × 58 mm. Subsequent imaging and evaluations suggested cranio-cervical instability, leading to surgical intervention. Conclusions. Prompt diagnosis of RCH with conservative or surgical management is essential to avoid neurological deficits and mortality. Despite the significant potential for morbidity and mortality, the majority of patients show a benign clinical course with conservative care, underscoring the importance of quick diagnosis and close observation.

Atypical Presentation of Meningoencephalitis in an Infant Caused by Meningococcemia and Complicated by Ventriculitis with Bilateral Extra Axial Septated Collection

Background: The diagnosis of meningitis in the infancy period is a challenging. Clinical evaluation and high index of suspicion with early empirical treatment guidelines continue to evolve and support physician efforts to decrease the morbidity and mortality associated with pediatric meningitis. Case report: We report a case of a previously healthy 2-month-old male who presented with excessive crying, preceded by subjective fever and watery diarrhea, for one day without any other symptoms. Parents gave multiple antipyretic doses at home for irritability which might mask his fever. The patient was tachycardic with an unremarkable physical exam. Full septic work-up done after stabilization of the patient and empirical antibiotics started. His blood culture grew Neisseria meningitides which caused meningoencephalitis and ventriculitis with bilateral extra-axial collection, the patient was in septic shock with multiple organ dysfunction. Conclusion: Meningococcal meningitis in the neonatal and infancy periods remains a serious health threat with high morbidity and mortality. This case report urges the physician to keep a high index of suspicion by taking detailed history and frequent assessment in each suspected cases as the clinical presentations, signs and symptoms in the infancy period are not specific nor classic to guide the physician.

Symptomatic calcified chronic subdural hematoma in an elderly patient: a case report

IntroductionCalcified chronic subdural hematoma is a rare and infrequent diagnosis made in clinical practice according to the literature. Calcification of chronic subdural hematoma is found more frequently in children and young adults than in the aged. The proposed mechanism of calcification may involve poor circulation and absorption in the subdural space together with intravascular thrombosis and prolonged existence of the hematoma in the subdural space.Clinical presentationAn 84-year-old Ethiopian male patient presented with progressive right-sided body weakness of 8-month duration. The weakness started in the right lower extremity and progressively involved the upper extremity. Associated with the above complaint, he had had also a globalized headache of the same duration. Pre- and post-contrast brain computed tomography scans showed a right hemispheric extra-axial collection that crossed the suture line, with a maximum depth of 2.3 cm. Subsequently, craniotomy and hematoma evacuation were carried out and the patient was discharged improved.ConclusionThe most common symptom of calcified chronic subdural hematoma is headache followed by lethargy, confusion, memory impairment weakness, and seizures. A diminished level of consciousness is relatively common and motor deficits are usually manifested as hemiparesis or gait disturbance. Most calcified chronic subdural hematomas can be diagnosed by computed tomography or magnetic resonance imaging and differentiated from the usual chronic subdural hematoma by imaging studies and gross pathology. Surgical treatment is advised in symptomatic patients when feasible, and often results in neurological improvement. Here we presented a patient with an uncommon calcified chronic subdural hematoma, which was successfully evacuated, resulting in a good recovery.

Imaging, Clinical, and Demographic Differences in Patients With Type III Spinal Cerebrospinal Fluid Leak (Cerebrospinal Venous Fistulas) Compared With Patients With Types I and II Spinal Cerebrospinal Fluid Leak.

Spinal cerebrospinal fluid (CSF) leaks are an underdiagnosed cause of neurologic symptoms. The most common types of spinal CSF leaks are from dural tears (type I) and meningeal diverticula (type II). Cerebrospinal fluid-venous fistulas (type III) are less common and underrecognized. The purpose of this study was to evaluate the intracranial and spinal imaging findings in patients with types I/II versus type III leaks. This was a retrospective, institutional review board-approved study performed on adult patients between January 2020 to September 2021 with surgically confirmed type I/II/III spinal CSF leak. Patients had preoperative brain magnetic resonance imaging (MRI) with contrast and medical records detailing symptoms and clinical diagnoses. Patients were excluded for nondiagnostic brain MRIs. Demographic and clinical information were recorded. The presence of extra-axial collections, pachymeningeal thickening, brain sagging, and decreased pontomamillary distance were evaluated on MRI. Seven patients had type III leaks, and 16 had type I/II leaks. Patients with type III leaks were older ( P = 0.0003) and had higher rates of initial misdiagnosis (100% vs 31%) and longer times to correct diagnosis ( P = 0.03) compared with type I/II leaks. Intracranial extra-axial collections were never seen with type III leaks but were seen in 50% of type I/II leaks. Pachymeningeal thickening and brainstem sagging occurred in nearly equal frequency between groups. Smaller pontomamillary distances were seen in type III leaks versus type I/II leaks ( P = 0.047). When evaluating patients with suspected spinal CSF leak, findings of older age, absence of intracranial extra-axial collections, and small pontomamillary distances may raise suspicion for type III versus type I/II leak.

ID:16405 Look Before You Leap: The Importance of Preoperative Imaging Prior to Intrathecal Therapies

An 84-year-old, male with longstanding chronic low back pain was referred to outpatient pain clinic for intrathecal drug delivery system planning. After the patient was deemed a candidate for placement, a pre-operative MRI of the spine was ordered which revealed an extra-axial T2 hyperintense collection overlying the right frontoparietal region measuring 1.8 cm in thickness with some associated mass effect (see image). This was later evaluated with CT imaging and determined to be a chronic right sided subdural hematoma.

Tuberculous myelitis: a prospective follow-up study.

BackgroundProspective studies regarding tuberculous myelitis are lacking. We aimed to prospectively evaluate patients with tuberculous myelitis to identify the features that distinguish tuberculous myelitis from other myelitis.MethodsThis was a prospective study. Patients presenting with paraparesis/quadriparesis, and MRI showing myelitis were included. All patients were subjected to clinical, neuroimaging, and laboratory evaluation. Diagnosis of definite tuberculous myelitis was made if GeneXpert test in CSF was positive. Probable tuberculous myelitis was diagnosed if there was evidence of tuberculosis elsewhere in the body. Patients were treated with methylprednisolone and antituberculosis treatment. Patients were followed for 6 months. We compared the clinical, laboratory, and neuroimaging parameters and response to treatment of tuberculous myelitis with other myelitis. P values were adjusted using the Benjamini-Hochberg (BH) procedure to control false discovery rate.ResultsWe enrolled 52 patients. Eighteen (34.6%) patients had tuberculous myelitis. Headache (P = 0.018) was significantly more common in tuberculous myelitis. The CSF protein (P < 0.001), and CSF cell count (P < 0.001) were significantly higher in tuberculous myelitis. On neuroimaging, a LETM was common in tuberculous myelitis. Spinal meningeal enhancement (14; 77.8%), extra-axial collection, and CSF loculation (6; 33.4%), arachnoiditis (3;16.7%), and concomitant spinal tuberculoma (2;11.1%) were other common imaging features of tuberculous myelitis. Tuberculous myelitis patients showed a better response (P = 0.025) to treatment.ConclusionTuberculous myelitis was seen in approximately 35% of all myelitis cases, in a high tuberculosis endemic zone. Headache, markedly elevated CSF protein and spinal meningeal enhancement were distinguishing features. Tuberculous myelitis patients responded well to corticosteroids.

Preexisting Ventricular Shunts Are Associated with Failed Evacuation of Acute Subdural Hematomas: Single-Institution Case Series of Complications and Management Strategies

The effect of ventricular shunts on radiographic outcomes after evacuation of acute subdural hematomas (aSDHs) has not yet been established. We studied a series of patients who had undergone craniotomy for aSDH, exploring a possible relationship between the occurrence of a postoperative extra-axial collection (EAC) and the presence of a ventricular shunt. We reviewed all craniotomies for convexity aSDH performed between July 2015 and June 2020. The medical record review included perioperative coagulation studies, platelet counts, and antiplatelet and anticoagulation agent use. Univariate and multivariate analyses were conducted to identify the factors associated with postoperative EACs and reevacuation. A total of 58 patients had undergone craniotomy for aSDHs, including 9 with ventricular shunts. The median age was 67 years (interquartile range, 54-78 years), and 40% of the patients were women. Of the 58 patients, 16 were taking antiplatelet agents, and 6 were taking anticoagulation agents. Ten patients had developed perioperative thrombocytopenia (platelet count, <100,000/μL). Twelve patients had perioperative coagulopathy (international normalized ratio, ≥1.5). A postoperative EAC >10 mm occurred in 17 patients (29.3%). Eight patients (13.8%) had undergone reevacuation. The presence of a shunt and an increasing preoperative aSDH size were independently associated with an EAC >10 mm (P= 0.013 and P= 0.003, respectively). Only the presence of a shunt predicted for the need for reevacuation (P= 0.001). The shunts were explanted (n= 3) or valves were adjusted (n= 3) in all but 3 cases. We found that a lack of brain reexpansion after aSDH evacuation worsens radiographic outcomes and was more common in patients with shunts. Increasing shunt valve resistance might help prevent the formation of large EACs after aSDH evacuation.

Synthetic MRI in subarachnoid haemorrhage

To evaluate the reliability of synthetic magnetic resonance imaging (SyMRI) for detecting complications associated with subarachnoid haemorrhage (SAH), such as ischaemic lesions, hydrocephalus, or bleeding complications. Twenty patients with SAH, who underwent a conventional brain MRI and a SyMRI on a 3 T MRI machine. Comparable conventional and synthetic T2-weighted fluid attenuated inversion recovery (FLAIR) images were acquired. The presence of ischaemic lesions, hydrocephalus, extra-axial blood collections as well as the volumes of grey matter (GMv), white matter (WMv), and cerebrospinal (CSFv) were compared. The acquisition times of both sequences was also analysed. The concordance between the two techniques was excellent for the detection of ischaemic lesions and extra-axial collections (kappa=0.80 and 0.88 respectively) and good for the detection of hydrocephalus (kappa=0.69). No significant differences were detected in the number of ischaemic lesions (p=0.31) or in the Evans index (p=0.11). The WMv and CSFv measures were also similar (p=0.18 and p=0.94, respectively), as well as the volume of ischaemic lesions (p=0.79). Compared to conventional MRI, the SyMRI acquisition time was shorter regardless of the number of sections (32% and 6% time reduction for 4 or 3 mm section thickness, respectively). SyMRI allows the detection of potential complications of SAH in a similar way to conventional MRI with a shorter acquisition time.

Complication Rates in Early Versus Late Cranioplasty-A 14-Year Single-Center Case Series.

Cranioplasty (CP) following decompressive craniectomy (DC) is a common neurosurgical procedure for cranial cosmesis and protection. There is uncertainty regarding the complication rates and potential benefits related to the timing of CP. To investigate the impact of the timing of CP on complication rates for different etiologies of DC. A retrospective chart review was performed of all CP cases between 2004 and 2018 for traumatic and nontraumatic indications of DC. Demographics, clinical characteristics, and complications were collected. Early and late CP were defined as replacement of the bone flap at ≤90 and >90 d following DC, respectively. A total of 278 patients were included, receiving 81 early and 197 late CPs. When analyzing all patients, early CP was associated with a statistically significant higher odds of any complication (odds ratio [OR]: 3.25, P<.001), reoperation (OR: 2.57, P=.019), hydrocephalus (OR: 6.03, P=.003), and symptomatic extra-axial collections (OR: 9.22, P=.003). Subgroup analysis demonstrated statistically significant higher odds of these complications only for the CP trauma subgroup, but not the nontrauma subgroup. The odds of complications postCP demonstrated a statistically significant decrease of 4.4% for each week after DC (Unit Odds Ratio [U-OR]: 0.956, P=.0363). In our retrospective series, early CP was associated with higher odds of postoperative complications compared to late CP in the trauma subgroup. Greater care should be taken in preoperative planning and increased vigilance postoperatively for complications with this potentially more vulnerable subpopulation. Future prospective controlled trials are needed to elucidate optimal timing for CP.

The Role of MR Imaging and MR Angiography in the Evaluation of Patients with Headache

BACKGROUND: Headache is one of the most common complaint in medical practice and the most often neurological symptom.&#x0D; AIM: The aim of our study was to estimate the frequency of abnormal magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) findings in patients with non-acute headache without focal neurological abnormalities.&#x0D; MATERIAL AND METHODS: The results of the MRI and MRA were retrospectively analyzed. As major abnormalities, we took into account tumor, stroke, extraaxial collection, Chiari malformations, and vascular pathology (aneurysm and arterial-venous malformation).&#x0D; RESULTS: Two hundred twenty-five patients fulfilled the criteria. Out of 225 patients with median age of 37 (18–85) years, 78% of the patients were female and 22% were male. In total, we found 8.4% of major abnormalities. On MRI head scan without MRA analysis, we found 50.7% of normal finding, 47.1% of minor abnormalities and 2.2% of major abnormalities. On MRA scan, we found we found 52.9% of normal finding, 40.9% of minor abnormalities, and 6.2% of major abnormalities.&#x0D; CONCLUSION: Our study demonstrates a low but important diagnostic yield of MRI and MRA examination for patients with non-acute headache without focal neurological abnormalities.

Neuroendoscopic treatment of arachnoid cysts in the paediatric population. Series results for 20 patients

IntroductionNeuroendoscopy has become an effective and safe treatment for arachnoid cysts in the paediatric population. We review the paediatric patients with arachnoid cysts treated by neuroendoscopy in our hospital and analyse the results. Material and methodsA retrospective analysis of 20 patients operated on from 2005 to 2018. The variables assessed are: gender, age, clinical presentation, cyst site, presence of hydrocephalus and/or extra-axial collections, endoscopic procedures and complications. Procedure success is defined as an improvement in symptoms and reduction in cyst size until end of follow-up. ResultsOur series comprised 13 males and 7 females (mean age: 64.6 months, range: 4–172 months). The most frequent site was suprasellar-prepontine (7), followed by intraventricular (6), quadrigeminal (3), interhemispheric (2) and Sylvian (2).A total of 70% (14/20) of patients had hydrocephalus at diagnosis, which increased to 85% in suprasellar-prepontine cysts and 100% in quadrigeminal cysts. Only 4/14 patients with required a ventriculoperitoneal shunt (median age at diagnosis: 12.5 months). Of these 4 patients, 3 developed severe shunt overdrainage.The procedure was successful in 60% (12/20) of the patients in the series. Success by location was 57% (4/7) in suprasellar cysts, 33% (1/3) in quadrigeminal cysts, 66% (4/6) in intraventricular cysts, 100% (2/2) in interhemispheric cysts and 50% (1/2) in Sylvian cysts. Treatment thus failed in 8 cases, with a mean time to failure of 12.12 months (range: 0–45 months). A new neuroendoscopic procedure was performed in 4 of these 8 cases (success in 2/4), a ventriculoperitoneal shunt was placed in 2 cases, a cystoperitoneal shunt was placed in 1 case and the remaining case was managed conservatively. Mean follow-up time was 52.45 months (range: 3–129 months). ConclusionsNeuroendoscopy is an effective and safe treatment for arachnoid cysts in paediatric patients that also enables managing associated hydrocephalus in most cases. The choice of neuroendoscopic procedure and success rate depend on cyst location. Younger patients have been found to have a higher shunt dependency rate. In these cases, measures to prevent shunt overdrainage are recommended.

Acute subdural hematoma of the posterior cerebral fossa

Our work is about a 28-year-old man, admitted to the emergency room for a head trauma. A cerebral CT was performed who shows a biconvex sub-tentorial extra-axial collection spontaneously hyperdense suggesting an extra dural hematoma of the posterior cerebral fossa. The surgical evacuation found that it was an acute subdural hematoma (ASDH) (A,B). The ASDH is a subdural blood collection, complicating venous more than arterial bleeding. with male predominance and an age between 20 and 40. Most commonly supra tentorial, Sub tentorial location is rare it represents less than 5%. The clinic associate alteration of consciousness, signs of focusing, vegetative manifestations and epilepsy. The diagnosis is based on a CT scan which shows an extra-axial hyperdense collection with more or less associated lesions. After medical management the treatment is surgical, based on the removal of the hematoma by suboccipital craniectomy.

Neuroendoscopic treatment of arachnoid cysts in the paediatric population. Series results for 20 patients.

Neuroendoscopy has become an effective and safe treatment for arachnoid cysts in the paediatric population. We review the paediatric patients with arachnoid cysts treated by neuroendoscopy in our hospital and analyse the results. A retrospective analysis of 20 patients operated on from 2005 to 2018. The variables assessed are: gender, age, clinical presentation, cyst site, presence of hydrocephalus and/or extra-axial collections, endoscopic procedures and complications. Procedure success is defined as an improvement in symptoms and reduction in cyst size until end of follow-up. Our series comprised 13 males and 7 females (mean age: 64.6 months, range: 4-172 months). The most frequent site was suprasellar-prepontine (7), followed by intraventricular (6), quadrigeminal (3), interhemispheric (2) and Sylvian (2). A total of 70% (14/20) of patients had hydrocephalus at diagnosis, which increased to 85% in suprasellar-prepontine cysts and 100% in quadrigeminal cysts. Only 4/14 patients with required a ventriculoperitoneal shunt (median age at diagnosis: 12.5 months). Of these 4 patients, 3 developed severe shunt overdrainage. The procedure was successful in 60% (12/20) of the patients in the series. Success by location was 57% (4/7) in suprasellar cysts, 33% (1/3) in quadrigeminal cysts, 66% (4/6) in intraventricular cysts, 100% (2/2) in interhemispheric cysts and 50% (1/2) in Sylvian cysts. Treatment thus failed in 8 cases, with a mean time to failure of 12.12 months (range: 0-45 months). A new neuroendoscopic procedure was performed in 4 of these 8 cases (success in 2/4), a ventriculoperitoneal shunt was placed in 2 cases, a cystoperitoneal shunt was placed in 1 case and the remaining case was managed conservatively. Mean follow-up time was 52.45 months (range: 3-129 months). Neuroendoscopy is an effective and safe treatment for arachnoid cysts in paediatric patients that also enables managing associated hydrocephalus in most cases. The choice of neuroendoscopic procedure and success rate depend on cyst location. Younger patients have been found to have a higher shunt dependency rate. In these cases, measures to prevent shunt overdrainage are recommended.

Imaging findings of penetrating spinal cord injuries secondary to stab wounds on magnetic resonance imaging in a tertiary trauma unit, South Africa.

BackgroundIn South Africa, the leading cause of spinal cord injuries is motor vehicle accidents, followed by violence-related injuries, including gunshot injuries and stab wounds. Controversy regarding management persists. Magnetic resonance imaging (MRI) is the gold standard to rule out surgical causes of neurological deficit.ObjectivesTo determine the spectrum of imaging findings in penetrating spinal cord injuries, specifically related to stab wounds, in a Tertiary Academic Hospital in the Free State province and whether these imaging findings influenced immediate surgical decision-making and outcomes of patients.MethodConsecutive sampling was used to retrospectively select patients who presented with spinal penetrating injuries secondary to stab wounds during the period 01 August 2013–30 September 2016 and received MRI investigation. Fifty-six patients were included. Magnetic resonance imaging investigations were reviewed by the authors, with documentation of MRI findings, relevant patient demographics and clinical information into Excel spread sheets. Statistical analysis was performed by the Biostatistics Department of the University of the Free State.ResultsThe most common MRI finding was a high signal intensity wound tract (96.6%), followed by cord signal changes (91.1%) and cord oedema (82.1%). Thirty-nine extra-axial collections were diagnosed in 30 penetrating injuries, of which only one had spinal compressive effects. Four patients (7.1%) demonstrated pseudo-meningoceles. None of the included patients had an indication for emergency spinal surgery on review of imaging.ConclusionMagnetic resonance imaging findings did not alter the surgical course of action in our study patients. Despite this, MRI is a valuable modality in evaluation of penetrating spinal cord injuries in the post-traumatic phase (<24 h) for the presence of pseudo-meningoceles that pose an infection and delayed complication risk.

Comparison between postmortem computed tomography and autopsy in the detection of traumatic head injuries

IntroductionThe aim of this study was to assess the agreement between postmortem computed tomography (PMCT) and autopsy in detecting traumatic head injuries. Materials and MethodsConsecutive cases of death that underwent both unenhanced PMCT and conventional autopsy were collected from our institution database during a period of 3 years and reviewed retrospectively. PMCT images were reviewed for the presence of fractures (cranial vault, skull base, facial bones and atlas/axis) and intracranial hemorrhage. Kappa values were calculated to determine the agreement between PMCT and autopsy reports. Results73 cases were included, of which 44 (60%) had head trauma. Agreement between PMCT and autopsy was almost perfect (κ = 0.95) for fractures and substantial (κ = 0.75) for intracranial hemorrhage. PMCT was superior to autopsy in detecting facial bone and upper cervical spine fractures, and intraventricular hemorrhage. However, in some cases thin extra-axial blood collections were missed on PMCT. ConclusionsThe agreement between PMCT and autopsy in detecting traumatic head injuries was good. Using a combination of both techniques increases the quality of postmortem evaluation because more lesions are detected.

Intracranial subdural empyemas and epidural abscesses in children

The authors conducted a retrospective analysis of a consecutive series of children with intracranial subdural empyemas (SEs) and epidural abscesses (EAs) to highlight the important clinical difference between these two entities. They describe the delays and pitfalls in achieving accurate diagnoses and make treatment recommendations based on clinical and imaging findings. They reviewed their experience with children who had presented with intracranial SE and/or EA in the period from January 2013 to May 2018. They recorded presenting complaint, date of presentation, age, neurological examination findings, time from presentation to diagnosis, any errors in initial image interpretation, timing from diagnosis to surgical intervention, type of surgical intervention, neurological outcome, and microbiology data. They aimed to assess possible causes of any delay in diagnosis or surgical intervention. Sixteen children with SE and/or EA had undergone evaluation by the authors’ neurosurgical service since 2013. Children with SE (n = 14) presented with unmistakable evidence of CNS involvement with only one exception. Children with EA alone (n = 2) had no evidence of CNS dysfunction. All children older than 1 year of age had sinusitis. The time from initial presentation to a physician to diagnosis ranged from 0 to 21 days with a mean and median of 4.5 and 6 days, respectively. The time from diagnosis to neurosurgical intervention ranged from 0 to 14 days with a mean and median of 3 and 1 day, respectively. Delay in treatment was due to misinterpretation of images, a failure to perform timely imaging, progression on imaging as an indication for surgical intervention, or the managing clinician’s preference. Among the 14 cases with SE, initial imaging studies in 6 were not interpreted as showing SE. Four SE collections were dictated as epidural even on MRI. The only fatality was associated with no surgical intervention. Endoscopic sinus surgery was not associated with reducing the need for repeat craniotomy. Regardless of the initial imaging interpretation, any child presenting with focal neurological deficit or seizures and sinusitis should be assumed to have an SE or meningitis, and a careful review of high-resolution imaging, ideally MRI with contrast, should be performed. If an extraaxial collection is identified, surgical drainage should be performed expeditiously. Neurosurgical involvement and evaluation are imperative to achieve timely diagnoses and to guide management in these critically ill children. EA = epidural abscess; SE = subdural empyema.

Erratum: Impact of extra-axial cerebrospinal fluid collection in frontal morphology after surgical treatment of scaphocephaly.

[This corrects the article on p. 215 in vol. 9, PMID: 30505617.].

Complications of subdural and depth electrodes in 269 patients undergoing 317 procedures for invasive monitoring in epilepsy.

Intracranial monitoring is fundamental to epilepsy surgery, with reported complication rates of 3-17%. We aimed to assess the differences in complication rates between subdural and depth electrodes. We conducted a retrospective review of 317 electrode implantation procedures. All documented abnormal postoperative findings were recorded in our study. Those that resulted in a significant alteration of treatment course, including neurologic deficit, long-term medication use, reoperation, or hospital readmission, were deemed clinically significant. When possible, findings were attributed to a particular electrode type based on relative location to each electrode. Postoperative abnormalities were associated with SDE placement in 152 (47.9%) procedures and 40 (25.2%) DE placements (p < 0.001). Twenty-nine (9.1%) clinically significant complications were seen in the subdural electrode (SDE) group compared to 10 associated with DEs (6.3%, p = 0.37). SDEs were associated with increased rates of any postoperative hemorrhage (p < 0.001) or extraaxial collection (p = 0.007). Subdural grid placement was associated with an increased risk of any extraaxial collection (odds ratio [OR 2.42), as well as clinically significant collections (OR 9.47). Previous craniotomy was found to be associated with any abnormal postoperative finding (OR 1.71) as well as radiographic hemorrhage (OR 1.99). Concurrent resection is also associated with abnormal findings (OR 1.83) and extraaxial collections (OR 2.37). The overall complication rate was 9.1%, with 13 procedures (4.1%) resulting in neurologic deficit. However, only two patients (0.6%) had permanent neurologic sequelae resulting from lead placement. Subdural electrodes appear to have an increased rate of abnormal postoperative findings, including hemorrhage and extraaxial collections; however, there was no difference in clinically significant findings. Subdural grids also appear to be associated with symptomatic extraaxial collections, and previous craniotomy increases the risk of hemorrhage. Overall, intracranial monitoring remains a safe and effective procedure for localization of operative seizure foci. Patient selection and risk education for various modalities is an essential aspect of preoperative evaluation.