Torcular Herophili Research Articles

EP08.12: Prenatal diagnosis of torcula herophili thrombosis: a report of three cases

EP08.12: Prenatal diagnosis of torcula herophili thrombosis: a report of three cases

Dandy-Walker malformation

The Dandy-Walker malformation is the most frequent cerebral malformation. It is defined by hypoplasia and upward rotation of the vermis cerebelli, acystic enlargement of the fourth ventricle and in total an enlarged posterior fossa with cranially shifted position of the lateral sinus, tentorium and torcula herophili. This malformation was first described by Dandy and Blackfan in 1914 then supplemented again by Taggart and Walker in 1942. The current description as Dandy-Walker malformation was introduced in 1954 by Bender. In addition to these classical findings, the Dandy-Walker malformation is characterized by other abnormalities and malformations of the central nervous system (CNS) including agenesis of the corpus callosum, heterotopia, occipital meningocele, visual deficits and epilepsy. Neurogenetic and imaging examinations have led to abetter understanding of this malformation.

Anatomical variations of the torcular Herophili: macroscopic study and clinical aspects.

The anatomical variations of the confluence of sinuses were examined, focusing on the continuity of the superior sagittal sinus (SSS) and the transverse sinuses (TSs). In the 142 specimens studied, there were 72 symmetric cases (50.7%) and 70 asymmetric cases (49.3%). The symmetric group (no dominant type) was categorized into 34 cases of bifurcation (23.9%) and 38 cases of confluence (26.8%). The asymmetric group was categorized into 54 cases of the right-dominant type (38.0%) and 16 cases of the left-dominant type (11.3%). The right-dominant type was further categorized into 38 partially-communicating (26.8%) and 16 non-communicating types (11.3%). The left-dominant type was categorized into 11 partially-communicating (7.7%) and 5 non-communicating types (3.5%). In summary, the SSS asymmetrically drained into one TS in about half of the cases studied. The right-dominant type was about three to four times as common as the left-dominant type. The draining pattern shown by the asymmetric group could provoke intracranial hypertension due to unilateral jugular vein obstruction. In order to avoid this risk in cases of neck dissection, jugular vein catheterization, or hypercoagulopathy, preoperative evaluations of the dural sinus variations via MR venography, three-dimensional CT, or plain X-ray of the skull are recommended.

Pressure Mapping and Hemodynamic Assessment of Intracranial Dural Sinuses and Dural Arteriovenous Fistulas with 4D Flow MRI.

The feasibility of 4D flow MR imaging to visualize flow patterns and generate relative pressure maps in the dural venous sinus in healthy subjects (n = 60) and patients with dural arteriovenous fistulas (n = 7) was investigated. Dural venous drainage was classified based on torcular Herophili anatomy by using 4D flow MR imaging-derived angiograms and magnitude images. Subjects were scanned in a 3T clinical MR imaging system. 4D flow MR imaging enabled noninvasive characterization of dural sinus anatomy and mapping of relative pressure differences.

P09.02: Typical and atypical dural sinus malformation imaging in the fetus: based on 4 cases

To describe the atypical imaging characteristic of dural sinus malformation in fetuses by ultrasound and MRI. We report a series of four fetuses with dural sinus malformation in Hubei Maternal and children's hospital from July, 2013 to February 2016. All the mothers undertook the prenatal MR imaging because of the intracranial space occupying lesions discovered by prenatal ultrasound. In all four cases, two of them represented the typical MR imaging of dural sinus ectasia with thrombosis in the vicinity of torcular Herophili (also known as sinus confluence), while in the other two cases lesions located mainly in superior sagittal sinus and transverse sinus separately. Two pregnancies were terminated, while the outcomes of other two cases were not available. Atypical location of the dural sinus malformation, such as superior sagittal sinus and transverse sinus, should be paid special attention to. Sonographer should realise the atypical sign of dural sinus malformation, and prenatal MRI is necessary to identify the lesion.

Dissociated recovery between dementia and parkinsonism by transvenous embolization of recurrent dural arteriovenous fistula

AbstractDementia and parkinsonism are rarely observed in dural arteriovenous fistula. Here, we report a case of a 63‐year‐old man with recurrent dural arteriovenous fistula, who developed progressive dementia and parkinsonism as a result of a dural arteriovenous fistula at the torcular herophili. A sinus thrombosis induced the abnormal cortical venous reflux from the isolated straight sinus, resulting in the deep venous congestion of the thalamus and basal ganglia, which led to dementia and parkinsonism. However, the third endovascular embolization ameliorated memory disturbance and apathy with a slight improvement of parkinsonism. Although recoveries from dural arteriovenous fistula‐associated neurological deficits are variable depending on the severity, duration and, furthermore, selective vulnerability of the responsible ischemic lesions, early treatment should be essential for better recovery.

An ovine model of cerebral catheter venography for implantation of an endovascular neural interface.

OBJECTIVE Neural interface technology may enable the development of novel therapies to treat neurological conditions, including motor prostheses for spinal cord injury. Intracranial neural interfaces currently require a craniotomy to achieve implantation and may result in chronic tissue inflammation. Novel approaches are required that achieve less invasive implantation methods while maintaining high spatial resolution. An endovascular stent electrode array avoids direct brain trauma and is able to record electrocorticography in local cortical tissue from within the venous vasculature. The motor area in sheep runs in a parasagittal plane immediately adjacent to the superior sagittal sinus (SSS). The authors aimed to develop a sheep model of cerebral venography that would enable validation of an endovascular neural interface. METHODS Cerebral catheter venography was performed in 39 consecutive sheep. Contrast-enhanced MRI of the brain was performed on 13 animals. Multiple telescoping coaxial catheter systems were assessed to determine the largest wide-bore delivery catheter that could be delivered into the anterior SSS. Measurements of SSS diameter and distance from the motor area were taken. The location of the motor area was determined in relation to lateral and superior projections of digital subtraction venography images and confirmed on MRI. RESULTS The venous pathway from the common jugular vein (7.4 mm) to the anterior SSS (1.2 mm) was technically challenging to selectively catheterize. The SSS coursed immediately adjacent to the motor cortex (< 1 mm) for a length of 40 mm, or the anterior half of the SSS. Attempted access with 5-Fr and 6-Fr delivery catheters was associated with longer procedure times and higher complication rates. A 4-Fr catheter (internal lumen diameter 1.1 mm) was successful in accessing the SSS in 100% of cases with no associated complications. Complications included procedure-related venous dissection in two major areas: the torcular herophili, and the anterior formation of the SSS. The bifurcation of the cruciate sulcal veins with the SSS was a reliable predictor of the commencement of the motor area. CONCLUSIONS The ovine model for cerebral catheter venography has generalizability to the human cerebral venous system in relation to motor cortex location. This novel model may facilitate the development of the novel field of endovascular neural interfaces that may include preclinical investigations for cortical recording applications such as paralysis and epilepsy, as well as other potential applications in neuromodulation.

The research of color-coded digital subtraction angiography in the normal cerebral hemodynamic parameters

Objective To investigate the value of color-coded digital subtraction angiography (iFlow) in the study of normal cerebral hemodynamic parameters, so as to set up parameter for normal cerebral hemodynamic. Methods From march 2013 to september 2016, We retrospectively analyze a total of 60 patients in wuhan general hospital of PLA. These patients were reexamined with digital subtraction angiography (DSA) due to follow-up for postembolization with aneurysms by naked coins, and were suspected as intracranial vascular diseases with normal angiography findings in DSA. In order to measure the time to peak (TTP) of contrast medium in region of interest (ROI). we set the ROI at these rigion: ROI-1: internal carotid artery bifurcation; ROI-2: cerebral middle artery bifurcation; ROI-3: the middle of superior sagittal sinus; ROI-4: torcular herophili area; ROI-5: the end of basilar artery. Results The TTPs of ROI-1 to ROI-4 in left internal carotid artery angiography and ROI-5 in left vertebral artery angiography are (2.70±0.37), (2.85±0.36), (7.98±1.54), (8.85±1.77), (3.02±0.58) s respectively. The TTPs of ROI-1 to ROI-4 in right internal carotid artery and ROI-5 in right vetebral artery angiography are (2.77±0.35), (2.87±0.36), (8.01±1.14), (8.77±1.26), (3.06±0.55) s respectively. Conclusion The technique of iFlow provides a reference value index in normal cerebral hemodynamic, and set up a noval method in the research of cerebral hemodynamic. Key words: Color-coded digital subtraction angiography; Cerebral perfusion; Hemodynamic; Time to peak

Torcular pseudomass: a potential diagnostic pitfall in infants and young children.

Incidental findings on brain MRI may constitute a diagnostic pitfall. We observed an incidental extra-axial midline rounded pseudomass between the torcular Herophili and the occipital squama, with spontaneous resolution, which we called "torcular pseudomass." We investigated the frequency, imaging features, natural history and developmental background of this finding in a large group of infants and young children. We conducted a single-center retrospective study by reviewing all brain MRIs performed in children younger than 3years between 2007 and 2013 in a specialized pediatric hospital. We looked for soft tissue (minimum 2mm thick) interposed between the torcula and the occipital squama on midsagittal T1 and T2 images; we recorded the maximal diameters and outcome. Of 2,283 the children who had brain MRIs during the study period, 291 (12.7%, 95% confidence interval [CI] 0.11, 0.14) presented with a torcular pseudomass (median age 4months, range 0days to 35months, 56% male). MRI features were the same in all of these children: T1 isointensity and T2 hyperintensity to the cerebral cortex, facilitated diffusion on diffusion-weighted imaging and apparent diffusion coefficient maps, and contrast enhancement. The median diameters were: anteroposterior, 5.8mm; transverse, 10.5mm; cranio-caudal, 20.6mm. Follow-up MRI was available in 34.7% (95% CI: 0.20, 0.40) of the children; median follow-up time was 18months. Among these children, 35.6% (95% CI: 0.26, 0.45) had total involution, 52.5% (95% CI: 0.26, 0.62) had partial involution and 4.1% (95% CI: 0.05, 0.18) showed stability. Redundant soft tissue in the torcular region, or torcular pseudomass, is not an infrequent finding in infants and young children. It should be considered a physiological tissue, reflecting the postnatal developmental process of the brain and cranial vault, without the need for further investigation or follow-up imaging studies.

Skull sclerosing epithelioid fibrosarcoma: A case report and review of the literature.

Sclerosing epithelioid fibrosarcoma (SEF) is an unusual variant of fibrosarcoma that was previously considered to be a low-grade tumor with an indolent course. The tumor occurs most commonly in the soft tissue of the limb, trunk, head and neck, and occasionally in the bone and visceral organs. The skull is a rare primary site for SEF, with only 3 cases reported to date. The current study reports a case of SEF occurring in the occipital bone of a 24-year-old man, who lacked neurological symptoms. Imaging revealed a large mass emanating from the occipital bone and involving the superior sagittal sinus, torcular herophili and adjacent brain tissue. Histological and immunohistochemical characteristics confirmed the diagnosis of SEF. The patient experienced local recurrence and distant metastasis at 10 and 15 months, respectively, subsequent to the resection of the primary mass. The current case and review of the literature suggest that skull SEF may behave clinically as an aggressive malignant sarcoma. Radiological findings indicated the biological and histopathological characteristics of the tumor. Thus, its clinical behavior and certain imaging features may suggest this diagnosis.

Microsurgical Treatment of Meningiomas in the Torcular Herophili Region.

The Torcular Herophili region of the brain is anatomically complex, and surgery in this area requires much skill and care. Retrospective analysis on 35 cases of meningiomas in the Torcular Herophili region treated by microsurgery and confirmed by pathology. Tumor resection range was evaluated using the Simpson grading criteria. Postoperative complications and tumor recurrence were evaluated. Patients were followed up. The Karnofsky performance status was used to evaluate neurologic functions. Magnetic resonance venography (MRV) and magnetic resonance imaging (MRI) revealed the extent of disease in all patients. Simpson level I excision was done in 27 patients, level II in 5 patients, and level IV in 3 patients. Gamma knife treatment after surgery was performed in 3 patients. Symptoms of increased intracranial pressure were relieved after surgery. No patient died, and no patient suffered from any relevant operative complications and disabilities. Pathology reported typical meningioma (World Health Organization [WHO] level I) in 32 patients, and atypical meningioma (WHO level II) in 3 patients. Thirty-two patients were followed up for 0.5 to 5 years: 1 patient relapsed 2 years after operation (Simpson level IV excision), and 2 patients relapsed 3 years after operation (one Simpson level I and one level II). These results indicated that MRV should be performed to confirm the exact relationship between the tumor and venous sinus. The operative approach should be planned according to the MRI results, and the venous sinus should be preserved. Gamma knife might be a beneficial auxiliary treatment of meningioma in the Torcular Herophili region.

Transumbilical arterial embolization of a large dural arteriovenous fistula in a low-birth-weight neonate with congestive heart failure

The purpose of this study was to report transumbilical arterial embolization of a large dural arteriovenous fistula (AVF) in a low-birth-weight neonate with congestive heart failure (CHF). A female neonate was delivered by cesarean section at 31 weeks of gestation. Her birth weight was 1538 g and Apgar scores were 6 at both 1 and 5 min. Because of dyspnea and retracted respiration immediately after birth, she required mechanical ventilation. Ultrasound revealed right cardiac overload and a large cystic mass at the posterior brain. Magnetic resonance imaging on day 1 showed a large dural AVF (dural sinus malformation with arteriovenous (AV) shunts) at the torcular herophili. Umbilical artery and vein catheterization were performed on the same day for neurointervention. CHF prompted emergency embolization on day 8. The transfemoral arterial route could not be used because of its small size and compromised femoral artery blood flow. Transumbilical arterial embolization shrank the AV shunts markedly, resulting in clinical improvement, thus requiring no further intervention. Follow-up angiography at 4 months confirmed no residual AVF. Her growth and development were normal at the last follow-up at age 4 years. This patient apparently was the lowest birth weight neonate with a large AVF successfully treated by embolization, which is usually performed through the transfemoral arterial route. The transumbilical arterial route is an alternative for neonates with birth weight <2000 g and very small femoral arteries.

E-006 Familial Incidence of the Congenital Torcular Dural Arteriovenous Shunt

PurposeThere are several hereditary disorders that are well known to be associated with arteriovenous malformations (AVMs) involving the central nervous system including Sturge-Weber, Klippel-Trenaunay-Weber, and Parkes-Weber syndromes as well as...

Primary intracranial leiomyosarcoma of the torcular Herophili associated with Fanconi anemia and allogenic stem cell transplantation

Fanconi anemia is associated with a high risk for developing malignant tumors. The occurrence of primary intracranial leiomyosarcoma, however, which in general has a poor prognosis, has not been described thus far. The purpose of this study is to report on management and outcome of leiomyosarcoma of the torcular Herophili associated with Fanconi anemia in a pediatric patient. A 12-year-old girl with Fanconi anemia presented with a primary intracranial leiomyosarcoma arising from the torcular Herophili and infiltrating the adjacent venous sinuses after previous allogenic hematopoietic stem cell transplantation. Radical tumor resection followed by radiotherapy resulted in tumor-free survival and good outcome at a 2-year follow-up. Despite occurrence of leiomyosarcoma in a site thought unfavorable for surgery, combined tumor resection and radiosurgery may yield excellent outcome.

Prenatal Diagnosis of Torcular Herophili Thrombosis

Prenatally diagnosed thrombosis of the torcular herophili is very rare, and it is sometimes misdisgnosed due to unfamiliarity. Sonography with color Doppler imaging is the key imaging modality for prenatal diagnosis of torcular herophili thrombosis. Typical prenatal sonographic findings include a well-defined triangular anechoic collection in the occipital region and an echogenic structure within the collection, which represents the thrombus. Fetal magnetic resonance imaging is usually used as an adjunctive modality for prenatal diagnosis, as it confirms the diagnosis by providing more precise anatomic information and better characterization of the lesion. We present 2 cases of thrombosis of an ectatic torcular herophili with serial sonographic and magnetic resonance imaging examinations, as well as a review of the literature regarding the prenatal diagnosis of torcular herophili thrombosis.

Reproducibility of cerebrospinal venous blood flow and vessel anatomy with the use of phase contrast-vastly undersampled isotropic projection reconstruction and contrast-enhanced MRA.

The chronic cerebrospinal venous insufficiency hypothesis raises interest in cerebrospinal venous blood flow imaging, which is more complex and less established than in arteries. For accurate assessment of venous flow in chronic cerebrospinal venous insufficiency diagnosis and research, we must account for physiologic changes in flow patterns. This study examines day-to-day flow variability in cerebrospinal veins by use of 4D MR flow and contrast-enhanced MRA under typical, uncontrolled conditions in healthy individuals. Ten healthy volunteers were scanned in a test-retest fashion by use of a 4D flow MR imaging technique and contrast-enhanced MRA. Flow parameters obtained from phase contrast-vastly undersampled isotropic projection reconstruction and contrast-enhanced MRA scoring measurements in the head, neck, and chest veins were analyzed for internal consistency and interscan reproducibility. Internal consistency was satisfied at the torcular herophili, with an input-output difference of 2.2%. Percentages of variations in flow were 20.3%, internal jugular vein; 20.4%, azygos vein; 6.8%, transverse sinus; and 5.1%, common carotid artery. Retrograde flow was found in the lower internal jugular vein (4.8%) and azygos vein (7.2%). Contrast-enhanced MRA interscan κ values for the internal jugular vein (left: 0.474, right: 0.366) and azygos vein (-0.053) showed poor interscan agreement. Phase contrast-vastly undersampled isotropic projection reconstruction blood flow measurements are reliable and highly reproducible in intracranial veins and in the common carotid artery but not in veins of the neck (internal jugular vein) and chest (azygos vein) because of normal physiologic variation. Retrograde flow normally may be observed in the lower internal jugular vein and azygos vein. Low interrater agreement in contrast-enhanced MRA scans was observed. These findings have important implications for imaging diagnosis and experimental research of chronic cerebrospinal venous insufficiency.

Torcular Herophili classification and evaluation of dural venous sinus variations using digital subtraction angiography and magnetic resonance venographies

The configurations of cerebral veins and dural venous sinuses differ not only between individuals, but also between the two brain hemispheres of an individual, making the anatomical classification of the cerebral veins difficult. We evaluated the superior dural venous sinuses and classified their types and variations using magnetic resonance venography (MRV) and digital substraction angiography (DSA). A total of 394 patients were studied retrospectively. Superior dural venous sinuses were evaluated and the confluence of the sinuses was classified on 2-dimensional time-of-flight MRV, contrast-enhanced 3-dimensional spoiled gradient recalled echo magnetic resonance imaging, and/or cerebral DSA. Confluens sinuum was divided into three types: true confluence, partial confluence, and non-confluence. Of the three types, partial confluence (type II) was most frequently seen. Co-dominance of the transverse sinuses was most frequently observed. An occipital sinus was observed in 15 % of the patients. There were statistically significant differences between the left transverse sinus agenesis and the presence of the occipital sinus (p < 0.001), between the co-presence of the partial confluence type torcular and the occipital sinus (p = 0.040), and between the co-presence of the fenestrated straight sinus and the occipital sinus (p = 0.010). Although anatomical variations of dural venous sinuses are seen frequently, classification of venous sinuses helps surgeons in preoperative evaluation and management, and prevention of possible complications. In this study, we think that a comprehensive evaluation and classification of dural venous sinuses is a significant contribution to the literature.

US and MRI findings of fetal dural sinus thrombosis: report of two cases

Thrombosis of fetal dural sinuses is an uncommon condition which has a fairly characteristic appearance on fetal ultrasound and MRI. The entity is first diagnosed on routine fetal ultrasound with color Doppler, and as a referral, fetal MRI is done to confirm the diagnosis or better description of the intracranial structures [1, 2]. There are few reports with imaging features and details of different clinical outcomes of these fetuses. Almost all of the cases in the literature presented with large retrocerebellar masses at torcular Herophili with variable extensions into the superior sagittal or transverse sinuses. The reported ultrasound and MRI findings of thrombi are almost the same. The thrombus is echogenic on gray-scale ultrasound with no flow on color Doppler. The thrombus is hyperintense on T1-weighted (T1W) images and hypointense on T2weighted (T2W) images on fetal MRI [1–6]. We present two cases of dural sinus thrombosis that align with characteristic ultrasound and MRI findings described in the literature. Our cases had a good clinical outcome following good neurological and developmental assessments.

Color Doppler Ultrasound and MRI Findings of Vein of Galen Malformation in a Newborn, a Case Report.

The Vein of Galen aneurysmal malformation (VGAM) is a rare intracranial arteriovenous anomaly that has usually been diagnosed prenatally. We reported a near term boy, 2,140 grams body weight, with a large VGAM, who was diagnosed prenatally by color Doppler ultrasound. After birth, his APGAR scores were 2, 4, and 8, respectively. An emergency cranial ultrasound was performed promptly when his vital sign began to be stable. The image revealed a huge dilatation of the great vein of Galen, measured about 1.9 x 2.0 x 3.8 cm. in diameter, with mixed venous and arterial flow profiles. Abnormal dilatation of the right internal carotid artery, and circle of Willis were also identified and likely to be an arterial feeder to choroidal artery which directly draining into the great vein of Galen. MRI, MRA, and MRV of the brain were performed on the following day and also showed a huge aneurysmal dilatation of a median vein of prosencephalon (precursor of the great vein of Galen) and marked dilatation of falcine sinus. Torcular herophili, both transverse / sigmoid sinuses and both internal jugular veins showed abnormal dilatation on MRA and MRV. Endovascular transarterial embolization was planned to performe on this patient but his vital sign was not stable. He finally expired from severe congestive heart failure after 5 days of life.

Relation between bilateral differences in internal jugular vein caliber and flow patterns of dural venous sinuses

We measured the calibers of the left and right internal jugular veins (IJV) and sizes of the left and right transverse sinuses (TS) in 91 cadavers, compared them between the left and right sides, and also evaluated the drainage patterns of the superior sagittal sinus (SSS) and straight sinus (=rectal sinus, RS) in the torcular Herophili. In addition, the running type of groove for the SSS was investigated. The results were as follows: (1) The right IJV was larger in 81.3 %, while the left IJV was larger in only 11.0 %. (2) The drainage pattern of the SSS was the right type in 73.6 %, intermediate type in 14.3 %, and left type in 12.1 %. (3) The drainage pattern of the RS was the right type in 27.5 %, intermediate type in 25.3 %, and left type in 47.3 %. (4) The running type of groove for the SSS was mostly consistent with the drainage pattern of this sinus. (5) Concerning the relationships among these findings including the size of the TS, the drainage pattern of the SSS was mostly consistent with the side showing a larger TS as well as the side showing a larger IJV. These results suggest that the pattern of drainage of the SSS into the left and right TS affects the size of the TS and the running type of groove for the SSS, and is also closely involved in the caliber of the IJV. A discussion of the embryological, genetic, and clinical implications of these results is presented.