Treatment of an Elusive Symptomatic Sinus Pericranii: Case Report and Review of the Literature

Sinus pericranii (SP) are abnormal vascular connections between extracranial scalp venous channels and intracranial dural sinuses. This vascular abnormality rarely results in significant sequelae, but in select cases, it can be symptomatic. We describe the case of a 7-year-old girl with an SP who experienced intermittent visual, motor, and sensory symptoms not previously described in the literature. Her symptoms resolved after surgical treatment of the SP. We propose a mechanism for her symptoms and the rationale for the role of neurosurgical intervention along with a review of the literature.

P.148 Children and teenagers with hydrocephalus: Are narrowed dural sinuses better predictors of shunt-failure than ventriculomegaly?

Background: Intracranial hypertension secondary to shunt-failure is a feared complication requiring cross-sectional imaging for diagnosis. We compared dural sinus narrowing and ventriculomegaly as predictors of shunt-failure. Methods: 60 head MRIs and 60 MR venographies of hydrocephalus patients age 0-18 years (n=25) were analyzed. MRI studies were included when f/u clinical data combined with intra-operative findings proved shunt-failure (positive Gold standard) or when MRI was available when the child was well (negative Gold standard). The absence or presence of concerning hydrocephalus was diagnosed. On MRV, the major dural sinuses were independently analyzed with respect to >50% narrowing, suggesting compression by increased CSF pressure. Ventriculomegaly and significant dural sinus narrowing was correlated to the presence/absence of shunt failure as per Gold standard. Results: Sinus narrowing substantially correlated with proven shunt-failure (Cohen’s kappa test 0.635/p<=0.00001 as per Fisher exact test) while ventriculomegaly correlated poorly (0.258/p=0.0751). Sensitivity/specificity was 0.69/0.92 for sinus narrowing and 0.43/0.81 for ventriculomegaly. Conclusions: In this patient cohort, dural sinus narrowing more reliably predicted shunt-failure compared to ventriculomegaly.

Augmented Reality for Retrosigmoid Craniotomy Planning

While medical imaging data have traditionally been viewed on two-dimensional (2D) displays, augmented reality (AR) allows physicians to project the medical imaging data on patient's bodies to locate important anatomy. We present a surgical AR application to plan the retrosigmoid craniotomy, a standard approach to access the posterior fossa and the internal auditory canal. As a simple and accurate alternative to surface landmarks and conventional surgical navigation systems, our AR application augments the surgeon's vision to guide the optimal location of cortical bone removal. In this work, two surgeons performed a retrosigmoid approach 14 times on eight cadaver heads. In each case, the surgeon manually aligned a computed tomography (CT)-derived virtual rendering of the sigmoid sinus on the real cadaveric heads using a see-through AR display, allowing the surgeon to plan and perform the craniotomy accordingly. Postprocedure CT scans were acquired to assess the accuracy of the retrosigmoid craniotomies with respect to their intended location relative to the dural sinuses. The two surgeons had a mean margin of davg = 0.6 ± 4.7 mm and davg = 3.7 ± 2.3 mm between the osteotomy border and the dural sinuses over all their cases, respectively, and only positive margins for 12 of the 14 cases. The intended surgical approach to the internal auditory canal was successfully achieved in all cases using the proposed method, and the relatively small and consistent margins suggest that our system has the potential to be a valuable tool to facilitate planning a variety of similar skull-base procedures.

Neonatal giant dural sinus ectasia: a multimodality imaging approach

Dural venous sinus ectasia is a rare anomaly characterised by the formation of a large vascular lake within the leaves of the dural sinuses, usually associated with thrombosis. These lesions can cause brain compression, cardiac insufficiency and disseminated intravascular coagulation, which may lead to poor prognosis. We present the case of a neonate who presented with an intracranial mass on prenatal ultrasound. Postnatal transcranial ultrasonography, cranial CT and cranial MRI demonstrated a large lesion predominantly occupying the dural sinus confluence, extending into the sagittal sinus, straight sinus and right transverse sinus. The left marginal sinus remains unfused and patent. Concomitant arteriovenous malformations were evident in the median interhemispheric fissure and the left Sylvian fissure. There are several published case reports and case series describing malformations of the dural sinuses in perinatal and neonatal patients in recent years, but this case is unique in that: (1) there is the presence of a vascular malformation concomitant to the dural sinus ectasia and (2) it highlights the importance of imaging in clinching the diagnosis of giant dural venous sinus ectasia, as it is often misdiagnosed as more common conditions such as extra-axial intracranial haemorrhage.

Dural venous sinus anatomy in children with external hydrocephalus: analysis of a series of 97 patients

Purpose To evaluate the anatomical variations of dural venous sinuses in children with external hydrocephalus, proposing a radiological grading of progressive anatomic restriction to venous outflow based on brain phase-contrast magnetic resonance venography (PC-MRV); to evaluate the correlation between positional plagiocephaly and dural sinuses patency; and to compare these findings with a control group to ascertain the role of anatomical restriction to venous outflow in the pathophysiology of external hydrocephalus. Methods Brain MRI and PC MRV were performed in 97 children (76 males, 21 females) diagnosed with external hydrocephalus at an average age of 8.22 months. Reduction of patency of the dural sinuses was graded as 1 (stenosis), 2 (complete stop) and 3 (complete agenesis) for each transverse/sigmoid sinus and sagittal sinus. Anatomical restriction was graded for each patient from 0 (symmetric anatomy of patent dural sinuses) through 6 (bilateral agenesis of both transverse sinuses). Ventricular and subarachnoid spaces were measured above the intercommissural plane using segmentation software. Positional plagiocephaly (PP) and/or asymmetric tentorial insertion (ATI) was correlated with the presence and grading of venous sinus obstruction. These results were compared with a retrospective control group of 75 patients (35 males, 40 females). Results Both the rate (84.53% vs 25.33%) and the grading (mean 2.59 vs mean 0.45) of anomalies of dural sinuses were significantly higher in case group than in control group. In the case group, sinus anomalies were asymmetric in 59 cases (right-left ratio 1/1) and symmetric in 22. A significant association was detected between the grading of venous drainage alterations and diagnosis of disease and between the severity of vascular anomalies and the widening of subarachnoid space (SAS). Postural plagiocephaly (39.1% vs 21.3%) and asymmetric tentorial insertion (35.4% vs 17.3%) were significantly more frequent in the case group than in the control group. When sinus anomalies occurred in plagiocephalic children, the obstruction grading was significantly higher on the flattened side (p ≤ 0.001). Conclusion Decreased patency of the dural sinuses and consequent increased venous outflow resistance may play a role in the pathophysiology of external hydrocephalus in the first 3 years of life. In plagiocephalic children, calvarial flattening may impact on the homolateral dural sinus patency, with a possible effect on the anatomy of dural sinuses and venous drainage in the first months of life.

No Arachnoid Granulations—No Problems: Number, Size, and Distribution of Arachnoid Granulations From Birth to 80 Years of Age

Introduction: The study aims to quantify changes in the number, size, and distribution of arachnoid granulations during the human lifespan to elucidate their role in cerebrospinal fluid physiology.Material and Methods: 3T magnetic resonance imaging of the brain was performed in 120 subjects of different ages (neonate, 2 years, 10 years, 20 years, 40 years, 60 years, and 80 years) all with the normal findings of the cerebrospinal fluid system (CSF). At each age, 10 male and 10 female subjects were analyzed. Group scanned at neonatal age was re-scanned at the age of two, while all other groups were scanned once. Arachnoid granulations were analyzed on T2 coronal and axial sections. Each arachnoid granulation was described concerning size and position relative to the superior sagittal, transverse, and sigmoid sinuses and surrounding cranial bones.Results: Our study shows that 85% of neonates and 2-year-old children do not have visible arachnoid granulations in the dural sinuses and cranial bones on magnetic resonance imaging. With age, the percentage of patients with arachnoid granulations in the superior sagittal sinus increases significantly, but there is no increase in the sigmoid and transverse sinuses. However, numerous individuals in different age groups do not have arachnoid granulations in dural sinuses. Arachnoid granulations in the cranial bones are found only around the superior sagittal sinus, for the first time at the age of 10, and over time their number increases significantly. From the age of 60 onwards, arachnoid granulations were more numerous in the cranial bones than in the dural sinuses.Conclusion: The results show that the number, size, and distribution of arachnoid granulations in the superior sagittal sinus and surrounding cranial bones change significantly over a lifetime. However, numerous individuals with a completely normal CSF system do not have arachnoid granulations in the dural sinuses, which calls into question their role in CSF physiology. It can be assumed that arachnoid granulations do not play an essential role in CSF absorption as it is generally accepted. Therefore, the lack of arachnoid granulations does not appear to cause problems in intracranial fluid homeostasis.

Chronic headache as a clinical manifestation of cerebral venous sinus thrombosis

Patients with cerebral venous thrombosis (CVT) pre-sent with a range of symptoms, which varies widely from headache to coma. Chronic occlusion of venous dural sinuses leads to the initiation of compensation processes, such as vascular collatera-lization, recanalization of the organized thrombus. Consequently, their efficacy determines disease course and severity. The purpose of our study was to highlight the clinical challenges while managing a patient with subcompensated CVT. Taking into account the fact that mild severity is observed in 20 % of cases, eventually, about a quarter of patients presenting with the headache of unclear etio-logy becomes unnoticed and results in low quality of life. To analyze the disease outcome and prognosis, we accurately studied compensation mechanisms, which occur in a patient due to cerebral venous sinus thrombosis, notably venous collateral circulation and thrombus recanalization. However, the most important “pitfall” of chronic dural sinuses occlusion, when not appropriately treated, is the fact that hemodynamic compensation also leads to a high risk of cerebrovascular events, which may lead to death or disabi-lity. The patient with cerebral venous thrombosis of the transverse and sigmoid sinuses manifested migraine-like headache with a vegetative issue and signs of increased intracranial pressure. Due to the absence of anticoagulant therapy, venous drainage through collateral pathways and recanalization of thrombosed sinuses were insufficient to maintain a cerebral blood supply, resulting in diffuse cerebral edema, secondary brain injury. After an accurate survey, diagnostic procedures, prescribing of individualized treatment, and long-term follow-up with correction of therapy the patient experienced regression of CVT symptoms. Cerebral MRI venography is an important tool for the diagnosis and prediction of the prognosis of this condition. Thus, patients with a long history of untreatable headache and signs of intracranial hypertension should undergo this procedure. To consider intracranial vascular events and outcomes, the venous hemodynamics should be evaluated. Moreover, it is often necessary to examine cerebral veins and sinuses, when hemorrhagic stroke does not correspond to cerebral arterial territories and has unclear etiology.