Straight Sinus Research Articles

Sinus Pericranii associated with Hypoplastic Straight Sinus and Persistent Falcine Sinus

Sinus Pericranii associated with Hypoplastic Straight Sinus and Persistent Falcine Sinus

Paroxysmal nocturnal hemoglobinuria with sagittal vein thrombosis as the initial presentation

Introduction: Paroxysmal nocturnal hemoglobinuria is a rare disease that presents with a variety of symptoms including hematuria, thrombosis, and other non-specific symptoms. Venous thrombosis is not uncommon in paroxysmal nocturnal hemoglobinuria (PNH). However, a thromboembolic event as the presenting symptom of PNH is rare and can be life-threatening, when affects the sagittal veins in the brain. Case Report: A 28-year-old female presented to the facility with left-sided hemiparesis. Initial workup revealed a right-sided subacute hemorrhagic infarct of the parietal lobe, and magnetic resonance imaging (MRI) venography demonstrated extensive venous thrombosis involving the sagittal, straight, and transverse sinuses, with secondary edema in the involved hemisphere. Thrombotic events may affect up to 50% of PNH patients and account for at least one-third of mortality in PNH. Although disease presentation in PNH is variable, cerebral venous sinus thrombosis as the first thrombotic event in disease presentation along with the absence of hematuria makes this case unique. High suspicion of thrombosis and a differential diagnosis of PNH should be considered in young patients presenting with these symptoms, even in the absence of hematuria. Ravulizumab has significantly reduced thrombotic events, and these therapies should be immediately commenced upon high suspicion of thrombosis. Allogeneic hematopoietic stem cell transplantation offers the only curative approach for PNH to date. Conclusion: Paroxysmal nocturnal hemoglobinuria is a very rare and life-threatening disease. Hematuria is not always present in this disease. Complement inhibitor therapy should be started immediately upon confirmation of the diagnosis to decrease future thrombotic events. Paroxysmal nocturnal hemoglobinuria patients may need allogeneic hematopoietic stem cell transplantation, which is the only curative approach available today.

Outflow Patency Correlates with Radiosurgical Outcomes of Lateral Sinus Dural Arteriovenous Fistula.

To explore the impact of outflow patency on radiosurgical outcomes of lateral sinus dural arteriovenous fistulas (DAVFs). We retrospectively examined 83 lateral sinus DAVFs treated with Gamma Knife radiosurgery (GKRS) between 1995 and 2020. Two neuroradiologists blinded to the therapeutic outcomes served as imaging evaluators on pre-GKRS digital subtraction angiography and magnetic resonance images. The sinovenous outflow of lateral sinus DAVF was scored using combined conduit score (CCS), ranging from 0 (total occlusion) to 8 (full patency). The patients' follow-up magnetic resonance and digital subtraction angiography images were used to validate the radiosurgical outcomes (obliteration or non-obliteration) of lateral sinus DAVF. Cox regression and Kaplan-Meier analyses were performed to determine the correlations between the variables and outcomes. Among the 83 cases, 60 (72%) lateral sinus DAVFs achieved obliteration after a GKRS at a median latency period of 24.5months. After adjustment for aggressive presentation, cortical venous reflux, straight sinus reflux, and optic nerve sheath enlargement, a CCS of >6 was independently associated with lateral sinus DAVF obliteration (hazard ratio: 2.335, P=0.007). The estimated 36-month probabilities of obliteration were 80% versus 53.6% for lateral sinus DAVFs with a CCS of >6 versus ≤6. Lateral sinus DAVFs with a CCS of >6, indicating a nearly patent sinovenous outflow, were more likely to be obliterated after GKRS. Sinovenous outflow patency is a factor associated with therapeutic outcomes in radiosurgery for lateral sinus DAVFs.

Ruptured aneurysm of the artery of Davidoff and Schechter: illustrative case.

BACKGROUNDThe artery of Davidoff and Schechter (ADS) is an uncommonly encountered meningeal branch originating from the posterior cerebral artery typically identified in the setting of pathology, often dural arteriovenous fistulas (DAVFs). Here, the authors describe the first reported case of an ADS aneurysm, discovered in the setting of subarachnoid hemorrhage (SAH) and complicating a high-grade DAVF.OBSERVATIONSA 57-year-old female presented after experiencing the worst headache of her life. Noncontrast computed tomography scanning of the head demonstrated SAH. Angiography revealed a high-grade DAVF centered around the anterior straight sinus, consistent with the Galenic subtype of tentorial DAVF. Predominant arterial supply was from the bilateral middle meningeal and occipital arteries. Vertebral artery imaging revealed a 12-mm irregular aneurysm. The prospect that the target artery represented the noneloquent ADS was confirmed by Wada testing. Given the fusiform nature of the aneurysm, treatment required concomitant coil embolization of the aneurysm and parent artery sacrifice. A week later, the DAVF was treated with liquid embolic. The patient tolerated treatment without neurological compromise.LESSONSThe authors describe the first reported case of an ADS aneurysm discovered in the setting of SAH complicating a high-grade DAVF and the lessons learned during our experience managing this unique pathology.

Modelling of the dilated sagittal sinuses found in multiple sclerosis suggests increased wall stiffness may be a contributing factor

The cross-sectional area of the superior sagittal sinus (SSS) is larger in multiple sclerosis than normal and correlates with disease severity and progression. The sinus could be enlarged due to a decrease in the pressure difference between the lumen and the subarachnoid space, an increase in wall thickness or increased wall stiffness. The cross-sectional area of the SSS and straight sinus (ST) were measured in 103 patients with multiple sclerosis and compared to 50 controls. The cross-sectional area of the SSS and ST were increased by 20% and 13% compared to the controls (p = 0.005 and 0.02 respectively). The deflection of the wall of the sinus was estimated. The change in pressure gradient, wall thickness or elastic modulus between groups was calculated by modelling the walls as simply supported beams. To account for these findings, the modelling suggests either a 70% reduction in transmural venous pressure or a 2.4 fold increase in SSS wall stiffness plus an 11% increase in wall thickness or a combination of changes. An increase in sinus pressure, although the most straight forward possibility to account for the change in sinus size may exist in only a minority of patients. An increase in sinus wall stiffness and thickness may need further investigation.

Morphometric evaluation of great vein of Galen and its clinical implications.

The Galenic venous system plays a vital role in the drainage of blood from deeper parts of the brain. This venous system is contributed by many major veins. These veins are located closer to the pineal gland making the surgical approach in this region difficult. Any accidental injury or occlusion of the vein of Galen could lead to devasting results. Thus, studying the dimensions of the vein of Galen is more important. Hence, we aimed to evaluate the morphometry and trajectory to the vein of Galen. About 100 computed tomographic venography records were evaluated and the length, diameter of vein of Galen, angle between straight sinus and vein of Galen and distance from internal occipital protuberance and roof of fourth ventricle to vein of Galen were studied. The mean length and diameter of vein of Galen were 9.8±2.7 and 4.08±1.04 respectively. The mean angle between straight sinus and vein of Galen was 64.2°. The mean distance between external occipital protuberance and roof of fourth ventricle to vein of Galen were 52±6.9 and 33.3±4.5 respectively. No significant morphometric differences were observed between the age groups as well as between the sexs. The results obtained from this study may be helpful for the neurosurgeons in better understanding of the anatomy of the Galenic venous system and to adopt a safe surgical approach to improve the efficacy of the surgeries of the pineal gland and also in the region of vein of Galen.

DELAYED CEREBRAL VENOUS SINUS THROMBOSIS (CSVT) AFTER AN INVASIVE MENINGIOMA RESECTION: AN UNCOMMON PRESENTATION OF A COMMON COMPLICATION

DELAYED CEREBRAL VENOUS SINUS THROMBOSIS (CSVT) AFTER AN INVASIVE MENINGIOMA RESECTION: AN UNCOMMON PRESENTATION OF A COMMON COMPLICATION

Changes in venous drainage after posterior cranial vault distraction and foramen magnum decompression in syndromic craniosynostosis.

The authors' objective was to measure the effect of posterior cranial vault distraction (PCVD) plus foramen magnum decompression (FMD) on dural sinus volume and venous flow in patients with syndromic craniosynostosis. The volumes of the sagittal, straight, transverse, and sigmoid sinuses of 5 consecutive patients with syndromic craniosynostosis who underwent PCVD+FMD were calculated in cubic centimeters with T2-weighted volumetric MRI sequences before surgery, immediately after surgery, and after the end of the distraction process. Tridimensional reconstructions of phase-contrast magnetic resonance angiography (PC-MRA) images were obtained with multiplanar reconstruction (MPR). The average total volume of all dural sinuses increased immediately after surgery (from 10.06 cm3 to 12.64 cm3) and continued to increase throughout the 30-day distraction period (from 12.64 cm3 to 14.71 cm3) (p = 0.04), except that the right sigmoid sinus remained stable after the initial increase. The most important increases were observed for the left transverse sinus (+113.2%), right transverse sinus (+104.3%), left sigmoid sinus (+91.3%), and sagittal sinus (+41.8%). Less important modifications were evident for the right sigmoid sinus (+33.7%) and straight sinus (+23.4%). Significant improvements in venous flow were noted on the tridimensional reconstructions of the PC-MRA images. Venous obstruction grading score improved in 4 patients (average [range] 2.4 [ 2-5]) (p = 0.023) and remained stable in 1 patient. All patients had chronic tonsillar herniation (CTH) (mean [range] 16.6 [8-26] mm), and 3 had syringomyelia. CTH showed improvement on the last follow-up MRI evaluation in 4 patients (mean [range] 10.5 [0-25] mm) and worsened from 15 mm to 19 mm in 1 patient. Syringomyelia improved in 2 patients and remained unchanged in 1. This study has provided the first radiological evidence of the impact of craniofacial surgery on dural sinus anatomy and venous drainage. The venous anomalies described in patients with syndromic craniosynostosis are not static, and PCVD+FMD triggers a dynamic process that can lead to significant modifications of intracranial venous drainage. The traction exerted by the distracted bone flap onto the occipitoparietal dura mater adherent to the inner calvaria may account for the enlargement of the dural sinus throughout the distraction period. The impact of these modifications on venous pressure, intracranial pressure, CTH, and hydrocephalus remains to be determined.

Retraction: A Transvenous Endovascular Approach in Straight Sinus has Minor Impacts on Chordae Willisii.

[This corrects the article DOI: 10.4103/0028-3886.355179].

Intracranial Magnetic Resonance Venography of Superior Sagittal Sinus, Straight Sinus and Cerebral Venous Channels: Normal Anatomy and Variations in North Indian Population

Abstract The intracranial dural venous sinuses can be injured leading to thrombosis with in the dural sinuses causing headache, abnormal vision, weakness of the face and limbs on one side of the body, and seizures.Magnetic Resonance Venography (MRV) is one of the preferred methods of evaluation of the cerebral venous sinus anatomy, variations and pathology, particularly in the diagnosis of venous sinus thrombosis. The purpose of this study is to evaluate the use of MRV to depict the normal intracranial venous anatomy and its variants in North Indian population which can help to avoid potential pitfalls in the diagnosis of dural venous sinus thrombosis, venous infarcts and venous hemorrhage. Aim:The purpose of this study is to evaluate the use of MRV to depict the normal intracranial venous anatomy and its variants in North Indian population, which can help to avoid potential pitfalls in the diagnosis of dural venous sinus thrombosis, venous infarcts and venous hemorrhage. Materials:The present study was undertaken in the Departments of Anatomy and Radiodiagnosis at a North Indian tertiary care teaching hospital over a period of two years. Magnetic Resonance Venograms (MRV) of patients attending the radiology department were used to study the normal anatomy and variations in the dural venous sinuses. 50 MRV scans of which 26 were of females and 24 of male, were included in the study. Anatomical variations and variations in drainage of the dural venous sinuses were assessed and statistical analysis was done. Results:For both superior sagittal sinus drainage and straight sinus drainage, the proportion of veins draining in right and left transverse sinuses and confluence of sinuses was significantly different in the two age groups (p<0.001) in both males and females. Partial splitting of superior sagittal sinus in anterior one third or posterior one third was also seen. Statistically significant findings were observed regarding the laterality for vein of Labbe & vein of Trolard. Conclusion:MR venography is an excellent diagnostic technique to visualise anatomy and anatomic variations of venous sinuses as observed in our study. The partial splitting of superior sagittal sinus in either anterior one third or posterior one third as seen in our study, can cause misdiagnosis of thrombosis. Hence, knowledge of normal anatomy and anatomic variations in the intracranial venous sinuses is very important to diagnose cerebral venous sinus thrombosis accurately.

Dilatation of the bridging cerebral cortical veins in childhood hydrocephalus suggests a malfunction of venous impedance pumping

Dogs with a naturally occurring form of hydrocephalus have an elevated transmural venous pressure leading to cortical vein dilatation. The purpose of this study is to discover if there is vein dilatation in childhood hydrocephalus and to estimate the pressure required to maintain any enlargement found. Children with hydrocephalus between the ages of 4 and 15 years were compared with a control group. Magnetic resonance venography (MRV) and flow quantification were performed. The arterial inflow, sagittal sinus and straight sinus venous outflow were measured and the outflow percentages compared to the inflow were calculated. The cross-sectional area of the veins were measured. There were a total of 18 children with hydrocephalus, compared to 72 age and sex matched control MRV’s and 22 control flow quantification studies. In hydrocephalus, the sagittal sinus venous return was reduced by 12.9%, but the straight sinus flow was not significantly different. The superficial territory veins were 22% larger than the controls but the vein of Galen was unchanged. There is evidence of a significant increase in the superficial vein transmural pressure in childhood hydrocephalus estimated to be approximately 4 mmHg. An impedance pump model is suggested to explain these findings.

Quantitative Evaluation of a Cross-Sectional Area of the Fetal Straight Sinus by Magnetic Resonance Imaging and Its Clinical Value

ObjectiveThe intracranial venous system plays an important role in ensuring blood circulation and a stable blood supply to the fetal brain. In the present study, a cross-sectional area of the fetal straight sinus was quantitatively evaluated by fetal magnetic resonance imaging (MRI) to explore the method's clinical value.MethodsThe clinical and MRI data of 126 normal fetuses in mid-to-late stage pregnancies were retrospectively analyzed. The “dominant” sequence of the fetal straight sinus was selected, and the cross-sectional area of the lumen was measured at each gestational age to obtain the normal range at different ages and to analyze the developmental pattern and characteristics of the fetal straight sinus.ResultsThere were statistically significant differences in the cross-sectional area of the fetal straight sinus among different gestational ages (P < 0.05). The cross-sectional area of the fetal straight sinus was positively correlated with gestational age (coefficient of determination = 0.6892, P < 0.05). That is, the cross-sectional area of the fetal straight sinus grew with increasing gestational age, and the regression equation was y = 0.27 x – 2.14 (P < 0.05). Additionally, there were five fetuses with cerebral venous abnormalities, including four with heart failure and one with venous sinus thrombosis.ConclusionQuantitative measurement of a cross-sectional area of the fetal straight sinus by MRI enhanced understanding of the anatomical features and developmental pattern of fetal cerebral veins and provided a reference for the clinical diagnosis of related diseases and investigation concerning pathogenesis.

Age related increase in internal jugular vein size parallels temporal development of periventricular white matter hyperintensities.

Age-related white matter hyperintensities are associated with cognitive impairment and dementia. Venous insufficiency has recently been proposed as a potential mechanism for the development of periventricular white matter hyperintensities based on the neuroanatomic distribution. The current study assesses age related changes of the internal jugular veins and its association with white matter hyperintensities. A retrospective study was performed assessing patients with computed tomography angiography (CTA) and magnetic resonance imaging (MRI) within a 4-week window. The size of the internal jugular veins, straight sinus, vein of Galen and internal cerebral veins were measured on the CT angiography. A normalized neck venous ratio was developed. Burden of white matter hyperintensities were quantified on MRI using periventricular/deep Fazekas scores. Association was assessed using correlation analysis and multrivariate linear modeling, and differences between groups were assessed using t test, ANOVA or Kruskal-Wallis test, using p < 0.05 for significance. One hundred eighty-two patients were included with a mean age of 65.2 ± 16.8 (51.6% females). Age was correlated with the normalized neck venous ratio (rs =0.25, p < 0.001), and, with both, the periventricular Fazekas (rs =0.63, p < 0.001) and the deep Fazekas (rs =0.57, p < 0.001) grades. The periventricular Fazekas score was positively correlated with the normalized neck venous ratio (rs =0.21, p=0.003), but not significant on multivariate analysis accounting for age. The internal jugular veins demonstrate age related increase in size, paralleling the progression of periventricular white matter hyperintensities. Age remains the strongest predictor of white matter hyperintensities. Further work is needed to evaluate any causal role of venous changes on white matter hyperintensities.

Cerebral Venous Thrombosis after SARS-CoV-2 Infection and Pfizer-BioNTech Vaccination against COVID-19.

In the last 3 years, COVID-19 pandemic has produced great impacts on global population in terms of health and social costs. Pneumonia represents only one of several pathologies associated to COVID-19 disease. Among these, the cerebral venous thrombosis (CVT), constitutes an important cause of stroke. Here, we report a case of CVT diagnosed approximately 2 weeks after first dose of Pfizer-BioNTech vaccination, in a patient affected by COVID-19 few months earlier. He presented with headache and severe asthenia. The laboratory tests put in evidence thrombocytopenia and D-dimer elevation. A brain magnetic resonance imaging (MRI) and a computed tomography (CT) demonstrated hemorrhagic and ischemic phenomena on the right ventral thalamic nuclei, left thalamus, hippocampal and parahippocampal regions and the splenium of the corpus callosum. The study revealed a poorly opacified vein of Galeno and straight sinus. Heparin administration improved his clinical status; platelets values also arose over time.

Occipito-transtentorial approach for falcotentorial meningiomas: how I do it

BackgroundFalcotentorial meningiomas are rare tumors that arise at the junction of the dural folds of the tentorium and falx cerebri, at the junction of the vein of Galen with the straight sinus with possible extensions along the course of the straight sinus. Surgery of falcotentorial meningiomas remains challenging due to the intimate neurovascular relationships in the posterior incisural space.MethodsWe describe the key steps of the occipito-transtentorial approach for falcotentorial meningiomas with a video illustration. The surgical anatomy is described along with the advantages and limitations of this approach.ConclusionThe occipito-transtentorial approach offers good surgical exposure and outcomes in carefully selected patients harboring falcotentorial meningiomas. Precise understanding of the relationship between the tumor and the internal cerebral veins, basal veins, and vein of Galen should be thoroughly analyzed as these structures may be infiltrated or displaced.

Sle With Antiphoslipid Antibody Syndrome And Autoimmune Hemolytic Anaemia Presenting Cerebral Venous Sinus Thrombosis - A Rare Combination

The combination of Antiphospholipid Antibody Syndrome (APS) and Autoimmune Haemolytic Anemia (AIHA) is extremely unusual. However, APS with underlying SLE has a well-documented link to Coomb’s positive AIHA. Antiphospholipid antibody syndrome and autoimmune haemolytic anaemia can cause cerebral venous sinus thrombosis, which is a rare neurologic symptom. We reported a 16- year-old girl reported to the neurology ward with a dull aching headache in the occipital region, as well as a fever. MRI and MRV of brain was done and showed thrombosis in the posterior half of superior sagittal sinus, right transverse, sigmoid and straight sinus. Anti-Ds DNA, ANA, and direct and indirect Coomb’s tests were all positive. Anti-Cardolipin IgM levels were high, and lupus anticoagulants (LA1 and LA2) were positive. The importance of recognizing an uncommon presentation of SLE with antiphospholipid syndrome and autoimmune haemolytic anemia (AIHA) with cerebral venous sinus thrombosis is highlighted in this case report. Bangladesh J Medicine 2022; 33: 220-223

A clinico-radiological study of deep cerebral venous thrombosis.

Isolated deep cerebral venous thrombosis (DCVT) may have different presentation and outcome compared to DCVT with additional sinus thrombosis. We compare clinico-radiological findings and outcomes of patients with isolated DCVT with those having additional sinus thrombosis. Forty-one DCVT patients with or without additional sinus thrombosis were included. Deep CVT was diagnosed if there was thrombosis of straight sinus, vein of Galen, internal cerebral vein, or basal vein of Rosenthal on MR venography (MRV). Isolated DCVT patients were classified as Group A and those with additional sinus thrombosis as Group B. The clinical features, risk factors, MRI findings, and outcomes at 1, 3, and 6months were compared between Groups A and B. Median age was 28years, and 22 (54%) were females. Eight (19.5%) patients were in Group A and 33 (80.5%) in Group B. Group B patients had shorter duration of illness (7 vs 30days; p = 0.01), frequent vomiting [25 (75.7%) vs 2 (25%); p = 0.01], and papilledema [13 (39%) vs 0 (0%); p = 0.04]. Risk factors were comparable. MRI revealed bilateral thalamic [5 (62.5%) vs 6 (18.2%)] and basal ganglia [(4 (50%) vs 6 (18.2%)] lesions more frequently in Group A. At 1month, 2 (6%) patients died in Group B and none in Group A, and 24 had good outcome (50% Group A and 60.6% in Group B). At 3months, 30 had good outcome (62.5% Group A and 80.6% in Group B). Improvement after 3months was negligible. Isolated DCVT is rare, and additional sinus thrombosis is associated with more severe illness and death. However, long-term outcomes in the survivors are similar between the two groups.

Sub-acute Changes on MRI Measures of Cerebral Blood Flow and Venous Oxygen Saturation in Concussed Australian Rules Footballers

BackgroundSports-related concussion (SRC) is common in collision sport athletes. There is growing evidence that repetitive SRC can have serious neurological consequences, particularly when the repetitive injuries occur when the brain has yet to fully recover from the initial injury. Hence, there is a need to identify biomarkers that are capable of determining SRC recovery so that they can guide clinical decisions pertaining to return-to-play. Cerebral venous oxygen saturation (SvO2) and cerebral blood flow (CBF) can be measured using magnetic resonance imaging (MRI) and may provide insights into changing energy demands and recovery following SRC.ResultsIn this study we therefore investigated SvO2 and CBF in a cohort of concussed amateur Australian Football athletes (i.e., Australia’s most participated collision sport). Male and female Australian footballers (n = 13) underwent MRI after being cleared to return to play following a mandatory 13-day recovery period and were compared to a group of control Australian footballers (n = 16) with no recent history of SRC (i.e., > 3 months since last SRC). Despite the concussed Australian footballers being cleared to return to play at the time of MRI, we found evidence of significantly increased susceptibility in the global white matter (p = 0.020) and a trend (F5,21 = 2.404, p = 0.071) for reduced relative CBF (relCBF) compared to the control group. Further, there was evidence of an interaction between sex and injury in straight sinus susceptibility values (F1,25 = 3.858, p = 0.061) which were decreased in female SRC athletes (p = 0.053). Of note, there were significant negative correlations between straight sinus susceptibility and relCBF suggesting impaired metabolic function after SRC.ConclusionsThese findings support the use of quantitative susceptibility mapping (QSM) and relCBF as sensitive indicators of SRC, and raise further concerns related to SRC guidelines that allow for return-to-play in less than two weeks.

154 Prenatal diagnosis of atretic parietal cephalocele: A case report

Introduction and aims of the study: The term cephalocele refers to the herniation of intracranial structures through a fetal skull defect. The reported incidence of cephaloceles is 0.8-4 per 10000 live births, while atretic cephaloceles account for 4-17% of the total. Our objective is to present the prenatal diagnosis of an atretic parietal cephalocele, highlight the diagnostic pitfalls and discuss post diagnosis dilemmas. Methods: We present the case of a 34-year-old pregnant woman who presented to our Obstetrics Ultrasound Department for the routine second trimester (anomaly) scan. Her medical and family history was uneventful. She was Gravida 1 Para 0 (G1P0). The ultrasound examination revealed a singleton live fetus with a gestational age of 23 weeks. Biparietal diameter, head and abdominal circumference, femur length, estimated fetal weight and amniotic fluid index were within the normal range for the gestational age of the pregnancy. Detailed scanning of the fetal head revealed a posterior protruding sac-like structure, which appeared to originate from the right lambdoid suture. The mass measured 22.6x27x16mm and did not appear to include brain tissue. MRI revealed the apparent elevation of the straight venous sinus, a pathognomonic feature of congenital atretic parietal cephaloceles. Discussion: Theories regarding the origin of cephaloceles have suggested persistence of neural crest remnants or fetal neural blebs. A common sonographic find is the vertical position of the straight sinus. Prognosis determination is challenging as the condition is rare and it depends on the presence of concurrent central nervous system abnormalities. Conclusions: Thorough evaluation of the fetal head during the second trimester anomaly scan is essential for the diagnosis of atretic cephaloceles. The use of MRI facilitates the differential diagnosis of sculp lesions such as sinus pericranii, teratomas, lipomas, sarcomas and cephaloceles. Timely and accurate prenatal detection allows more time for parental counselling and delivery planning.

A Transvenous Endovascular Approach in Straight Sinus Has Minor Impacts on Chordae Willisii.

Cerebral dural sinuses contain different types of chordae willisii (CW). The transvenous endovascular approach, which has become an optimal method for the treatment of cerebrovascular diseases, such as malformation, fistula, and chronic intracranial hypertension, due to sinus thromboses, frequently uses retrograde navigation through dural sinuses. Whether or how much the endoscopic procedure damages the chordae willisii is often not well-assessed. In our study, an overall number of 38 cadaveric heads were analyzed for the distribution and features of the chordae willisii in the straight sinus. We used an endoscope on these samples mimicking a mechanical thrombectomy procedure performed in the straight sinus. Both endoscopic gross observation and light microscopic histological examination were used to assess the damages to the chordae willisii by the procedure. We found that the valve-like lamellae and longitudinal lamellae structures were mainly found in the posterior part of straight sinus whereas trabeculae were present in both anterior and posterior portions. We treated a group of samples with a stent and another with a balloon. The stent-treated group had a significantly higher rate of Grade 1 damage comparing with the balloon-treated group (p = 0.02). The incidence of damage to the surface of chordae willisii was also higher in the stent-treated group (p = 0.00). Neither the use of stent nor of balloon increased the rate of damage to chordae willisii during repeated experiments. These findings indicated that stent or balloon navigation through the straight sinus can cause minor damages to the chordae willisii and frequent uses of retrograde navigation through the straight sinus do not appear to increase the rates of damage to chordae willisii.