Magnetic Resonance Imaging of Dural Sinus Malformation in a Fetus: A Case Report

BACKGROUND

Dural sinus malformation (DSM) is a rather rare congenital condition that can be encountered in the fetus and infants. The cause and etiology of DSM remain unclear. Obstetric ultrasound plays a key role in screening fetal brain malformations, and MRI is frequently used as a complementary method to confirm the diagnosis and provide more details.

OBJECTIVE

Here, we present a fetus with DSM by multiple imaging methods to help better understand the imaging characteristics of this malformation.

CASE PRESENTATION

A 22-year-old primipara was referred to our hospital at 25 weeks of gestation following the detection of a fetal intracranial mass without any symptoms. A prenatal ultrasound performed in our hospital at 25 + 2 gestational weeks showed a large anechoic mass with liquid dark space, while no blood flow was detected. After the initial evaluation, this primipara received a prenatal MRI in our hospital. This examination at 25 + 5 gestational weeks delineated a fan-shaped mass in the torcular herophili, which was iso-to hyperintense on T1WI and hypointense on T2WI. At the lower part of this lesion, a quasi-circular hyperintense on T1WI and a signal slightly hyperintense on T2WI could be seen. Meanwhile, the adjacent brain parenchyma was compressed by the mass.

CONCLUSION

We reviewed the current literature to obtain a better understanding of the mechanisms, imaging characteristics, and survival status of DSM. Although the primipara of the present study regretfully opted for elective termination of pregnancy, the reevaluation of DSM survival deserves more attention because of the better survival data from recent studies.

Giant Arachnoid Granulations: Diagnostic Workup and Characterization in Three Symptomatic Adults

Giant arachnoid granulations (GAGs) are poorly investigated. Here, we document clinical findings associated with five new GAGs and illustrate the anatomical composition of these structures as well as diagnostic considerations in three symptomatic adults. The GAGs ranged from 1.1 to 3.6 cm (mean, 2.2 cm) in maximum dimension and manifested in middle-aged individuals who presented with long-standing brain mass and/or chronic headache. On imaging examinations, the tissues appeared as irregular parasagittal and/or perisinus structures that demonstrated heterogeneous internal elements. The GAGs abutted dura, extended through calvarial marrow spaces, and impinged on dural venous sinuses, causing their stenosis. The histologic workup of two GAG specimens resected from separate individuals revealed central collagen with pronounced internal vascular proliferation. One specimen additionally exhibited reactive changes within the lesion, including venous thrombosis, hemorrhage, and conspicuous inflammation. The salient immune component consisted of a foam cell-rich infiltrate that obstructed subcapsular and internal sinusoidal GAG spaces. Within this specimen, meningothelial hyperplasia was also appreciated. Notably, proliferated lymphatic vascular elements were additionally observed within the structure, extending into deep central collagen regions and engulfing many extravasated erythrocytes in the subcapsular space. In both surgically treated patients, symptoms resolved completely following resection. This report is the first to definitively depict reactive vascular and immunological changes within GAGs that were clinically associated with headache. The frequency of reactive changes within these meningeal structures is unclear in the literature, as GAGs are rarely sampled and investigated. Further systematic analyses are warranted to elucidate the causes and consequences of GAG genesis and their roles in physiology and disease states.

Acquired dural arteriovenous fistula after cerebellopontine angle meningioma: A case report

RATIONALE

Intracranial brain surgeries, including ventriculostomy, burr hole, craniotomy, and craniectomy, are the most common causes of acquired dural arteriovenous fistula (dAVF). Here we report a case of acquired dAVF after a cerebellopontine angle meningioma surgery.

PATIENT CONCERNS

A 51-year-old woman was diagnosed with a 40-mm cerebellopontine angle meningioma. The patient underwent surgery via a retrosigmoid suboccipital approach. A small craniotomy and an additional craniectomy were performed. At 7 months after the surgery, she presented with pulsating tinnitus and headache.

DIAGNOSIS

Magnetic resonance imaging and digital subtraction angiography showed a dAVF that was fed by the occipital artery and drained into transverse and sigmoid sinuses.

INTERVENTIONS

We performed Onyx® (Irvine, CA) embolization.

OUTCOMES

The patient's symptoms completely improved.

LESSONS

Craniectomy defects, partially exposed sinuses, and incomplete cranioplasty might be risk factors for iatrogenic dAVF after a retrosigmoid suboccipital craniotomy or craniectomy. Complete reconstructive cranioplasty is an essential procedure to prevent a direct connection between the venous sinus and the external carotid artery.

Brain herniation (encephalocele) into arachnoid granulations: prevalence and association with pulsatile tinnitus and idiopathic intracranial hypertension

PURPOSE

Brain herniation into arachnoid granulations (BHAG) of the dural venous sinuses is a recently described finding of uncertain etiology. The purpose of this study was to investigate the prevalence of BHAG in a cohort of patients with pulsatile tinnitus (PT) and to clarify the physiologic and clinical implications of these lesions.

METHODS

The imaging and charts of consecutive PT patients were retrospectively reviewed. All patients were examined with MRI including pre- and post-contrast T1- and T2-weighted sequences. Images were reviewed separately by three blinded neuroradiologists to identify the presence of BHAG. Their location, signal intensity, size, presence of arachnoid granulation, and associated dural venous sinus stenosis were documented. Clinical records were further reviewed for idiopathic intracranial hypertension, history of prior lumbar puncture, and opening pressure.

RESULTS

Two hundred sixty-two consecutive PT patients over a 4-year period met inclusion criteria. PT patients with BHAG were significantly more likely to have idiopathic intracranial hypertension than PT patients without BHAG (OR 4.2, CI 1.5-12, p = 0.006). Sixteen out of 262 (6%) patients were found to have 18 BHAG. Eleven out of 16 (69%) patients had unilateral temporal or occipital lobe herniations located in the transverse sinus or the transverse-sigmoid junction. Three out of 16 (19%) patients had unilateral cerebellar herniations and 2/16 (13%) patients had bilateral BHAG.

CONCLUSION

In patients with PT, BHAG is a prevalent MRI finding that is strongly associated with the clinical diagnosis of IIH. The pathogenesis of BHAG remains uncertain, but recognition should prompt comprehensive evaluation for IIH.

Dural sinus collapsibility, idiopathic intracranial hypertension, and the pathogenesis of chronic migraine

Available evidences suggest that a number of known assumption on idiopathic intracranial hypertension (IIH) with or without papilledema might be discussed. These include (1) the primary pathogenetic role of an excessive dural sinus collapsibility in IIH, allowing a new relatively stable intracranial fluids pressure balance at higher values; (2) the non-mandatory role of papilledema for a definite diagnosis; (3) the possibly much higher prevalence of IIH without papilledema than currently considered; (4) the crucial role of the cerebral compliance exhaustion that precede the raise in intracranial pressure and that may already be pathologic in cases showing a moderately elevated opening pressure; (5) the role as "intracranial pressure sensor" played by the trigeminovascular innervation of dural sinuses and cortical bridge veins, which could represent a major source of CGRP and may explain the high comorbidity and the emerging causative link between IIHWOP and chronic migraine (CM). Accordingly, the control of intracranial pressure is to be considered a promising new therapeutic target in CM.

Endovascular stenting for idiopathic intracranial hypertension with venous sinus stenosis

OBJECTIVES

Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure of unknown etiology and venous sinus stenting may be an optional treatment. We aimed to evaluate the effects of venous sinus stenting on visual function, intracranial pressure, and trans-stenotic pressure gradient of the patients with IIH and to determine effects of baseline BMI or weight changes on subjective vision outcome and intracranial pressure.

METHODS

From July 2009 to Aug 2016, 88 eligible patients with IIH and venous sinus stenosis who underwent stenting were retrospectively studied.

RESULTS

In this study, 67 women and 21 men were included with an average age of 39.01 (18-60) years. The average BMI was 26.75 kg/m² . Here, 66 (75.9%) patients had papilledema, 39 had impaired vision before stenting; 57 patients were followed-up, 48 (84.2%) showed significant subjective improvement or recovery in visual acuity, 4 (7.0%) patients reported no significant change in visual functions, and 5 (8.8%) suffered permanent vision loss. The cerebrospinal fluid opening pressure and trans-stenotic pressure gradient were significantly decreased postoperatively. Baseline BMI was associated with pre-and postoperative trans-stenotic pressure gradients, as well as changes in cerebrospinal fluid opening pressure. However, baseline BMI and body weight changes during follow-up were not necessarily associated with subjective visual outcomes after stenting. Stenting efficacy was limited in patients with severe preoperative optic symptoms.

CONCLUSIONS

Venous sinus stenting represented an effective treatment for resolving visual dysfunction and intracranial pressure associated with venous sinus stenosis. BMI seemed to be associated with intracranial pressure but not subjective visual outcomes after stenting.

Idiopathic intracranial hypertension in a paediatric population: a retrospective observational study on epidemiology, symptoms and treatment

Idiopathic intracranial hypertension (IIH) is a disorder of unknown origin, which is characterized by elevated intracranial pressure (ICP) without underlying etiological evidence of neurological disease. The purpose of the current study was to evaluate epidemiological features, clinical presentation, diagnostic findings and treatment of sixteen children (7 males and 9 females) with IIH. Medical records of the patients were obtained from the University Paediatric Hospital of Catania, Italy. Clinical features, investigations and treatment approaches were retrieved. The mean age of the sixteen children at onset of symptoms was 9 years (range: 4 to 16 years). Most of the patients were classified as pre-pubertal. Mean BMI was 28.9 kg/m2. In 93.75% of patients headache was the presenting clinical symptom; and in the same percentage papilledema was detected as the accompanied sign during diagnostic flow-chart. The mean lumbar puncture opening pressure (LPOP) was 350 mm H2O. Fifty percent of the cases had normal brain imaging, while 12.5% showed enlarged optic nerve diameter and one patient had an intraocular protrusion of the optic nerve on MRI. Two patients (12.5%) had venous sinus stenosis, and one case showed an abnormal spinal MRI. With regard to therapeutic approaches, 93.75% of the cases were successfully treated with Acetazolamide. None of the patients required surgical procedures, and all neuroimaging findings disappeared after receiving treatment. In the present study we investigated the association of IIH with venous sinus stenosis. We also found ocular ultrasound to be a useful non-invasive alternative method for determining papilledema in paediatric IIH, specifically in an emergency.

Lessons from surgical outcome for intracranial meningioma involving major venous sinus

Intracranial meningiomas involving the major venous sinus (MVS) pose several complication risks upon performing radical resection. Some surgeons consider MVS invasion a contraindication for a complete resection of meningioma, and others suggest total resection followed by venous reconstruction. The aim of the study was to analyze our surgical results and discuss management strategy for intracranial meningiomas involving the MVS. Between 1993 and 2011, 107 patients with intracranial meningiomas involving MVS underwent surgery in our institution. Clinicoradiological features including pathological features and operative findings were retrospectively analyzed. Median follow-up duration was 60.2 months (range, 6.2-218.2 months). Distributions of tumor cases according to the involved sinus were as follows: 86% parasagittal, 10.3% tentorial, and 3.7% peritorcular. Simpson Grade I/II removal was achieved in 93 of 107 patients (87%). Partially or totally occluded MVS by their meningiomas (Sindou classification IV and V) was found in 39 patients (36%). Progression rate was 12% (13/107) and progression-free survival rates were 89%, 86%, and 80% at 5, 7, and 10 years, respectively. Sindou classification (IV/V) and Karnofsky performance status (KPS) score 6 month after the surgery (KPS < 90) were predictive factors for progression in our study (P = 0.044 and P = 0.001, respectively). The resection degree did not reach statistical significance (P = 0.484). Interestingly, there was no progression in patients that underwent radiation therapy or gamma knife radiosurgery for residual tumor. There were no perioperative deaths. Complication rate was 21% with brain swelling being the most common complication. There was no predictive factor for occurrence of postoperative complication in this study. In conclusion, complete tumor resection with sinus reconstruction did not significantly prevent tumor recurrence in intracranial meningioma involving MVS. Considering the complications from this procedure as it has possibly related with reduced postoperative KPS score, the tumor should be removed as much as possible while leaving remnant portion with significant invasion of sinus or drainage vein. Following radiation therapy or gamma knife radiosurgery for a remnant or recurred meningioma might then be justified.

Occlusion of Posterior Fossa Dural Sinuses in Vein of Galen Malformation

BACKGROUND AND PURPOSE

Spontaneous or progressive occlusion of the posterior fossa dural sinuses is often observed in patients with vein of Galen malformation, which can affect the clinical course. The aim of this study was to examine the patency of the posterior fossa dural sinuses in patients with vein of Galen malformation and to analyze the clinical and angiographic course of this condition.

MATERIALS AND METHODS

We retrospectively reviewed 61 consecutive children with vein of Galen malformations. Clinical presentation, management, outcome, and angiographic change were analyzed for the patients with attention paid to all dural sinus occlusions.

RESULTS

Twenty patients (32.8%) demonstrated spontaneous sinus occlusion, mostly in the sigmoid sinus. This condition was not observed in neonates and was first discovered during infancy or childhood. Progression of sinus occlusion was seen in 10 patients, and the conditions of 6 of them deteriorated in accordance with the progression of sinus occlusion. After total or subtotal obliteration of the malformation by transarterial glue embolization, 13 patients recovered to healthy, 3 patients had only mild developmental delay, and 4 patients remained neurologically disabled.

CONCLUSIONS

Spontaneous sinus occlusion is not a rare condition and can result in neurologic deterioration in the natural history of untreated vein of Galen malformation. If signs of progressive sinus occlusion are noticed, early arteriovenous shunt reduction or elimination by transarterial glue embolization is expected to prevent permanent brain damage.

[Mother and son with enlarged parietal foramina, persistent fetal vein, and ALX4 mutation]

Enlarged parietal foramina (EPF) are rare congenital skull defects. These round or oval defects are situated on each parietal bone approximately 1 cm from the midline. Most patients with EPF have a positive family history. The condition is inherited as an autosomal dominant trait with relatively high, but not full, penetrance. Mutation in either MSX2 or ALX4 genes is associated with enlarged parietal foramina. Case 1 is a boy who was noticed to have a large anterior fontanelle, large posterior fontanelle, and widely opened sagittal suture at 2 months. During development, the anterior fontanelle and sagittal suture closed at 3 years and the posterior fontanelle subsequently divided into two foramina with ossification of the midline bridge by 4 years. The foramina were about 2.5 x 2.5 cm in diameter at 8 years. Case 2 is the 34-year-old mother of Case 1. She showed similar bone defects in her cranium, again about 2.5 x 2.5 cm in diameter. Neither patient showed any neurological symptoms. Genetic analysis revealed a mutation in the ALX4 gene in both patients, and magnetic resonance imaging showed a persistent falcine sinus and a hypoplastic straight sinus. Further evaluation revealed that the mother of Case 2 also had a mutation in the ALX4 gene, but no enlarged parietal foramina. Although high penetrance of this condition has been reported, this family suggests incomplete penetrance of this disorder.

Pulsatile tinnitus caused by a dilated left petrosquamosal sinus

The emissary veins, like the petrosquamosal sinus (PSS), are residual valveless veins, which connect the intracranial dural venous sinuses and the extracranial venous system. Rarely, they may cause pulsatile tinnitus (PT). A 22-year-old woman developed in the first week of puerperium worsening headaches, vomiting, and diplopia, and the accentuation of a PT in the left ear that she presented for eight years. The clinical examination findings nine days after delivery were unremarkable, with the exception of a left sixth nerve palsy, and a peculiar sensibility of the left temporo-mandibular joint. High-resolution computed tomography (HRCT) revealed an osseous canal in the air cells of the left temporal bone compatible with a PSS. CT and magnetic resonance (MR) imaging÷MR-venogram detected signs of thrombosis of the superior sagital sinus, and of the left lateral sinus. Laboratory tests revealed severe inherited thrombophilia. We used antithrombotic therapy (body weight-adjusted subcutaneous low-molecular weight heparin for three weeks, followed by indefinite therapy with warfarin), and the headaches, vomiting, and diplopia resolved within four days of treatment. A follow-up MR-venogram performed two weeks later indicated complete recanalization of the intracranial dural venous sinuses. The PT was improved after two weeks of medical therapy, so she could adapt to it without intervention on the PSS. The early initialization of an efficient medical therapy had a great impact on her favorable evolution. PSS could be identified in her case on HRCT.

Diploic arteriovenous fistulas--classification and endovascular management

BACKGROUND

The authors report on two cases of diploic arteriovenous fistulas (AVFs) in the left parieto-occipital region of a 20-year-old female and the right parietal region of a 68-year-old male. The clinical presentation, angiographic appearance, and endovascular management of these rare lesions are discussed.

METHODS

Retrospective data from two patients with diplopic AVFs are examined with a review of all published cases of diploic arteriovenous fistulas.

RESULTS

Where previously reported diploic AVFs showed venous drainage to be intracranial or combined, two case studies examined by the authors found exclusively extracranial drainage in the AVFs. In both case studies the lesions were primarily fed by the middle meningeal artery and treated via a transarterial endovascular approach using n-BCA glue.

CONCLUSIONS

After reviewing all reported cases of AVF in the literature and combining our two new observations, we concluded that diploic AVFs can have three types of venous outflow: draining toward dural sinuses only, toward extracranial veins only, and combining the dural and extracranial pathways.

Non-puerperal uterine inversion in a patient with intracranial sigmoid sinus thrombosis and facial palsy

Non-puerperal uterine inversion and cranial nerve palsies in patients with sigmoid sinus thrombosis are both extremely rare. We report a case of a patient who presented with both simultaneously. The symptoms of sigmoid sinus thrombosis resolved with subcutaneous enoxaparin, and an abdominal dissection with removal of the uterus vaginally resulted in a successful outcome for the patient.

[Sinus pericranii; a congenital swelling on the scalp]

BACKGROUND

Sinus pericranii is a rare congenital disorder of the skull. It involves a venous connection between the intracranial and extracranial venous systems caused by a defect at the level of a cranial sinus.

CASE DESCRIPTION

We present the case of a 20-year-old woman with a soft compressible swelling on the back of her head from birth. MRI examination revealed sinus pericranii. The treatment consisted of coagulating the venous connection and closing the cranial malformation.

CONCLUSION

In a patient with soft-tissue swelling on the back of the head that has been present since birth, differential diagnostics should extend beyond epidermoid cysts alone and also include consideration of sinus pericranii. This is particularly important if the swelling is in the midline.

The role of dural sinus stenosis in idiopathic intracranial hypertension pathogenesis: the self-limiting venous collapse feedback-loop model

In recent years the efficacy of endovascular venous stenting in idiopathic IIH treatment has been consistently reported, strongly suggesting that sinus stenosis should be viewed as a causative factor rather than a secondary phenomenon. We propose that in subjects carrying one or more collapsible segments of large cerebral venous collectors and exposed to a number of different promoting factors, sinus venous compression and cerebrospinal fluid (CSF) hypertension may influence each other in a circular way, leading to a new relatively stable venous/CSF pressures balance state at higher values. The mechanism relay on self-limiting venous collapse (SVC) feedback-loop between the CSF pressure, that compresses the sinus, and the consequent venous pressure rise, that increases the CSF pressure. The result is the "coupled" increase of both pressure values, a phenomenon not expected in presence of sufficiently rigid central veins. Once the maximum stretch of venous wall is reached the loop stabilize at higher venous/CSF pressure values and become self-sustaining, therefore persisting even after the ceasing of the promoting factor. Notably, the SVC is reversible provided an adequate perturbation is carried to whichever side of the loop such as sinus venous stenting, on one hand, and CSF diversion or even a single CSF withdrawal by lumbar puncture (LP), on the other. The SVC model predicts that any condition leading to an increase of either, cerebral venous pressure or CSF pressure may trigger the feedback loop in predisposed individuals. Migraine with and without aura, a disease sharing with IIH a much higher prevalence among women of childbearing age, is associated with waves of significant brain hyperperfusion. These may lead to the congestion of large cerebral venous collectors and could represent a common SVC promoting condition in susceptible individuals. The SVC model give reason of the high specificity and sensitivity of sinus stenosis as IIH predictor and of the multiplicity of the factors that have been found associated with IIH. Moreover it might explain why, among the sinus stenosis carriers, young and overweight women are at higher risk of developing the disease. Finally, the SVC model fully explain the enigmatic longstanding remissions that can be commonly observed after a single LP with CSF subtraction in IIH with or without papilledema.

Clinical features and underlying causes of cerebral venous thrombosis in Japanese patients

The clinical symptoms, causative factors, and prognosis in Japanese patients with cerebral venous thrombosis have not been adequately characterized. The present study describes these features in patients in Japan. Twenty-two patients with cerebral venous thrombosis were retrospectively identified. Diagnosis was confirmed by either digital subtraction angiography, magnetic resonance venography, or contrast-enhanced computed tomography. Demographic data and clinical and radiological features were recorded and analyzed for each patient. Prognosis was evaluated by the modified Rankin scale (mRS) at the time of hospital discharge. The most frequent symptom of cerebral venous thrombosis was headache (59.1 %). Causative factors included congenital thrombophilia (31.8 %), acquired thrombophilia (27.3 %), and iron-deficiency anemia (13.6 %). Of seven patients with congenital thrombophilia, four had mutations in the protein S gene, two had mutations in the protein C gene, and one had mutations in the antithrombin gene. All patients were alive at discharge from hospital. Nineteen of the 22 patients (86.4 %) recovered completely or exhibited only mild residual symptoms (mRS 0-2). However, three patients (13.6 %) had a poor prognosis (mRS 3-5). Cerebral venous thrombosis in Japanese patients is frequently associated with congenital thrombophilia and protein S gene mutation.

[Thrombosis of the sinus durae matris as a complication of therapy in patients with Hodgkin lymphoma]

AIM

To describe thrombosis of the sinus durae matris (TSDM) in lymphomas.

SUBJECTS AND METHODS

402 patients with Hodgkin lymphoma were treated using the BEACOPP-14 protocol in 2006 to 2013. Thrombotic events occurred in 6% of the patients, including 3 (0.8%) who developed brain magnetic resonance imaging-verified TSDM.

RESULTS

TSDM developed in 3 women aged 17, 18, and 25 years during 3-6 chemotherapy cycles involving glucocorticosteroids in a dose of 80 mg/m2 on days 1-7 and an oral contraceptive used continuously for 1.5-3 months. The symptoms of thrombosis were severe headache; 2 patients had convulsive syndrome with short-term loss of consciousness. Anticoagulant therapy with intravenous heparin 20,000--24,000 U/day led to thrombus recanalization within 4-10 days. No rethromoboses were observed during a subsequent follow-up.

CONCLUSION

The BEACOPP-14 treatment in young women with Hodgkin lymphoma who continuously take oral contraceptives should be combined with anticoagulant therapy, by monitoring their coagulogram.

Prenatal diagnosis of torcular herophili thrombosis: report of 2 cases and review of the literature

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.

In utero magnetic resonance imaging for diagnosis of dural venous sinus ectasia with thrombosis in the fetus

BACKGROUND

Dural venous sinus ectasia with thrombosis (DVSET) in the fetus is a rare condition that can be diagnosed prenatally with the use of fetal MR imaging, yet with limited indication of long-term clinical significance.

OBJECTIVE

To describe and evaluate the diagnostic value of fetal MR imaging in the prenatal diagnosis of dural venous sinus ectasia with thrombosis and its clinical significance.

MATERIALS AND METHODS

We report a series of nine fetuses with dural venous sinus ectasia with thrombosis. The mothers, located in four feto-maternal centres, were referred for fetal MR imaging due to space occupying lesions identified on second-trimester antenatal ultrasound.

RESULTS

In all but one case the dural venous sinus ectasia with thrombosis was in the vicinity of the venous confluence (VC) with various extension in the posterior dural sinuses. Antenatal follow-up imaging was performed in seven cases and showed progression in one, stable appearances in one and regression in five cases. Three pregnancies were terminated. In the remaining six cases there was no reported neurological deficit at up to 44 months of clinical follow-up.

CONCLUSION

This is among the largest series of postnatal clinical follow-up in cases of prenatal diagnosis of dural venous sinus ectasia with thrombosis in the literature. Clinical follow-up suggests a good prognosis when antenatal follow-up shows partial or complete thrombus resolution.

Dural arteriovenous malformations of the skull base

Dural arteriovenous malformations (AVMs) are interesting lesions, which can present as diagnostic and therapeutic challenges. Such AVMs were initially described as located solely in the dural venous sinuses, but during the last decade researchers have discovered them in other locations such as the tentorium and foramen magnum. It is understandable that they can develop in other locations because numerous arteriovenous shunts normally occur all over the dura. Early reports emphasize that they are congenital; however, some investigators have proposed that they are acquired lesions arising after sinus thrombosis and trauma. They also have variable clinical features. From 1975 to 2000 we treated 400 AVMs, of which 46 were dural. Of these 46 dural AVMs, 18 could be classified as skull base AVMs. We restricted the designation of skull base AVMs to those AVMs located in the tentorium or adjacent to bones of the skull base. Two of these AVMs actually had their vascular nidus located in the bone. The common dural sinus AVMs were excluded from this category. The presenting clinical features of these skull base AVMs ranged from headache and pulsatile tinnitus to intracranial hemorrhage. They were treated by a combination of endovascular and microsurgical treatment. The majority of patients had a good clinical outcome. Skull base dural AVMs are an interesting clinical entity. Their clinical course, treatment and final outcome are variable depending on their location. They should be managed by a multidisciplinary approach.

Reflux venous flow in dural sinus and internal jugular vein on 3D time-of-flight MR angiography

INTRODUCTION

Reflux venous signal on the brain and neck time-of-flight magnetic resonance angiography (TOF MRA) is thought to be related to a compressed left brachiocephalic vein. This study is aimed to assess the prevalence of venous reflux flow in internal jugular vein (IJV), sigmoid sinus/transverse sinus (SS/TS), and inferior petrosal sinus (IPS) on the brain and neck TOF MRA and its pattern.

METHODS

From the radiology database, 3,475 patients (1,526 men, 1,949 women, age range 19-94, median age 62 years) with brain and neck standard 3D TOF MRA at 3 T and 1.5 T were identified. Rotational maximal intensity projection images of 3D TOF MRA were assessed for the presence of reflux flow in IJV, IPS, and SS/TS.

RESULTS

Fifty-five patients (1.6%) had reflux flow, all in the left side. It was more prevalent in females (n = 43/1,949, 2.2%) than in males (n = 12/1,526, 0.8%) (p = 0.001). The mean age of patients with reflux flow (66 years old) was older than those (60 years old) without reflux flow (p = 0.001). Three patients had arteriovenous shunt in the left arm for hemodialysis. Of the remaining 52 patients, reflux was seen on IJV in 35 patients (67.3%). There were more patients with reflux flow seen on SS/TS (n = 34) than on IPS (n = 25).

CONCLUSION

Venous reflux flow on TOF MRA is infrequently observed, and reflux pattern is variable. Because it is exclusively located in the left side, the reflux signal on TOF MRA could be an alarm for an undesirable candidate for a contrast injection on the left side for contrast-enhanced imaging study.

Clinical and angiographic results of patients with dural arteriovenous fistula

Endovascular embolization has been regarded as the primary treatment for dural arteriovenous fistula (dAVF). The aim of this study was to describe our experience with treatment and outcomes for patients with dural AVF, and to determine optimal treatment modalities. Between November 2007 and March 2011, 43 patients with dAVF (14 cavernous sinus, 20 transverse-sigmoid sinus, and nine patients with other types) were admitted to our Institute for treatment. For cavernous sinus dAVF, transvenous embolization was attempted as the first-line treatment with residual AVF obliterated by transarterial embolization (TAE), except for three patients who were treated conservatively. For transverse-sigmoid sinus dAVF, TAE was the primary treatment method. Nine of 14 (64.3%) patients with cavernous sinus dAVF had complete angiographic resolution. For transverse-sigmoid sinus dAVF, 14 of 17 (82.4%) patients were treated by TAE using Onyx Liquid Embolic System (eV3 Neurovascular, Irvine, CA, USA). Nine of these patients (64.3%) were angiographically cured or improved clinically with no serious complications, and the other five (35.7%) patients showed significant reductions in arteriovenous shunt. The other nine dAVF were treated by TAE or surgical disconnection depending upon the accessibility of the lesion and risk of complications. Six of nine (66.7%) patients had complete angiographic obliteration or clinical improvement. With developments in diagnostic tools and endovascular interventions, dAVF have become an important neurovascular issue. The results of this study suggest that a new approach to treatment of dAVF is needed.

Evaluation of the effect of hemoglobin or hematocrit level on dural sinus density using unenhanced computed tomography

PURPOSE

To identify the relationship between hemoglobin (Hgb) or hematocrit (Hct) level and dural sinus density using unenhanced computed tomography (UECT).

MATERIALS AND METHODS

Patients who were performed UECT and had records of a complete blood count within 24 hours from UECT were included (n=122). We measured the Hounsfield unit (HU) of the dural sinus at the right sigmoid sinus, left sigmoid sinus and 2 points of the superior sagittal sinus. Quantitative measurement of dural sinus density using the circle regions of interest (ROI) method was calculated as average ROI values at 3 or 4 points. Simple regression analysis was used to evaluate the correlation between mean HU and Hgb or mean HU and Hct.

RESULTS

The mean densities of the dural sinuses ranged from 24.67 to 53.67 HU (mean, 43.28 HU). There was a strong correlation between mean density and Hgb level (r=0.832) and between mean density and Hct level (r=0.840).

CONCLUSION

Dural sinus density on UECT is closely related to Hgb and Hct levels. Therefore, the Hgb or Hct levels can be used to determine whether the dural sinus density is within the normal range or pathological conditions such as venous thrombosis.

Endovascular management of sigmoid sinus dural arteriovenous fistula associated with sinus stenosis in an infant

A 4-month-old female presented with a dural arteriovenous fistula (DAVF), which was successfully managed using endovascular techniques. There are very few case series reporting DAVF in infants younger than 12 months and, to our knowledge, only 60 pediatric patients with DAVF have been reported to date. Although most DAVF have a benign course, they can result in life-threatening hemorrhage. Endovascular therapies are usually indicated in the management of these neurosurgical vascular malformations. Endovascular therapy of DAVF in neonatal patients presents some major issues. Gaining arterial access may be problematic in femoral arteries too small for the introduction of a sizeable guiding catheter. The volumes of contrast and infused fluids must be carefully monitored to prevent fluid overload. Radiation exposure should be restricted as far as possible. This report contributes to the limited body of evidence on neonatal DAVF and its endovascular management.

Sinus venous stenosis, intracranial hypertension and progression of primary headaches

The recently advanced hypothesis that idiopathic intracranial hypertension without papilledema (IIHWOP) is a powerful risk factor for the progression of pain in individuals prone to episodic primary headache implies that IIHWOP is much more prevalent than it is believed to be in the general population and that it can run almost asymptomatic in most of the affected individuals. In this review, we discuss the evidence available supporting that: (a) sinus venous stenosis-associated IIHWOP is much more prevalent than believed in the general population and can run without symptoms or signs of raised intracranial pressure in most of individuals affected, (b) sinus venous stenosis is a very sensitive and specific predictor of intermittent or continuous idiopathic intracranial hypertension with or without papilledema, even in asymptomatic individuals, (c) in primary headache prone individuals, a comorbidity with a hidden stenosis-associated IIHWOP represents a very common, although largely underestimated, modifiable risk factor for the progression and refractoriness of headache.

[The arrest of bleeding from the sigmoid sinus and the upper segments of internal jugular vein]

The objective of the present work was to develop an efficacious non-injurious technique for the arrest of hemorrhage from the sigmoid sinus and the upper segments of the internal jugular vein. The authors proposed a relatively simple and highly effective method to be used to the blockade of the sigmoid sinus. It was employed to treat 8 patients none of whom suffered complications in the late postoperative period (the follow-up study lasting from 6 months to 2 years after the intervention).

Cerebral venous sinus thrombosis in Saudi Arabia

OBJECTIVE

To analyze the clinical patterns, etiologies, treatment, and outcome of cerebral venous sinus thrombosis (CVST) in 2 major cities of Saudi Arabia, Jeddah and Al-Baha.

METHODS

One hundred and eleven patients diagnosed as CVST were identified from the medical records at King Abdulaziz Medical City, Jeddah, and King Fahad Hospital, Al-Baha, Saudi Arabia, from January 1990 through November 2010. We retrospectively analyzed the data, compared it with local and international studies, and reviewed the literature.

RESULTS

There were 92 adults and 19 children. Among adults, females predominated, while more boys were affected than girls. The mean age of onset was 29.5 years. The most common clinical presentations were headache, focal neurologic deficits, seizures, papilledema, and decreased level of consciousness. The main risk factors identified were pregnancy/ puerperium, antiphospholipid antibody syndrome, oral contraceptive pills, malignancy, and infections. Multiple sinuses were affected in 51 patients (45.9%). When a single sinus was involved, the superior sagittal sinus (24.3%) was the most common. Seventy-four patients recovered completely, 23 patients recovered partially, and 10 patients died. Bad prognostic factors included incurable co-morbid conditions, late presentation, and status epilepticus.

CONCLUSION

Pregnancy/puerperium was the most common etiological factor in our series. Clinical features were similar to international series. Behcet`s disease was not a major etiological factor in our series. Most patients had involvement of multiple sinuses. Prompt treatment with anticoagulation resulted in complete or partial recovery in 87.4% of patients.

Spontaneous otogenic pneumocephalus

The diagnosis and management of spontaneous otogenic pneumocephalus with literature review is described. A young sportsman experienced headache and fluctuating mass in his occiput during increased physical activity. A large extradural intracranial pneumocephalus with corresponding emphysema was imaged on a CT scan. Transmastoid identification and plugging of temporal bone defect solved the problem with complete pneumocephalus and emphysema resorption.

Temporo-sylvian arachnoidal cyst and an extreme pneumatization of the cranial sinuses: a case report

We present a patient who showed MRI evidence of a giant temporo-sylvian arachnoidal cyst of the left hemisphere and an extreme pneumatization of the sphenoid and frontal sinuses. No sign of mass effect or cerebral atrophy was detected. This patient presented a deficit of memory and control functions, but quality of life was not affected. Surgery was not performed. Arachnoidal cyst and anatomic variants of the sinus region have not a common etiology. This is the first report that describes a giant temporo-sylvian arachnoidal cyst with anatomic variants of the paranasal sinuses.

Intracranial dural arteriovenous fistula presenting as parkinsonism and cognitive dysfunction

There are few syndromes of parkinsonism with dementia which can be treated. We report two patients with dural arteriovenous fistula (DAVF) who presented with rapidly progressive parkinsonism and cognitive dysfunction. DAVF are rare lesions resulting from abnormal connections between meningeal arteries and dural sinuses. Angiography in both patients revealed DAVF associated with multiple occlusive changes in the dural venous sinus. This report emphasizes the need for a high level of clinical suspicion to diagnose DAVF and consider it as one of the causes of rapidly progressive cognitive dysfunction in patients with parkinsonism.

Transverse-sigmoid sinus dural arteriovenous fistulae

Transverse-sigmoid sinus dural arteriovenous fistulae are abnormal arteriovenous communications within the dural wall of the transverse-sigmoid sinuses. They present with a variety of clinical features, ranging from benign bruits to intracranial hemorrhage and neurologic deficits. The presentation and natural history of these fistulae are largely determined by the pattern of venous drainage. Knowledge of natural history and careful study of the angioarchitecture by angiography is therefore mandatory for correct management of these lesions. In this review, anatomy and pathology, principles of management, and the various factors that influence treatment decisions are discussed, with a focus on endovascular therapy. Indications for endovascular treatment, therapeutic goals, approaches, and techniques are reviewed. The role of surgical treatment is also briefly discussed.

Headache in Cerebral Venous Thrombosis: incidence, pattern and location in 200 consecutive patients

We analyzed the incidence, pattern and location of headache in consecutive 200 patients with proven diagnosis of CVT to identify an association between localization of headache and site of sinus involvement. Headache was present in 136 (68%) patients. The duration of headache (reported in 128 patients) was reported as acute (1–3 days), 81 patients (60%); sub-acute (4–14 days), 33 patients (24%); and chronic (more than 14 days), 14 patients (10%). The quality of headache (reported in 72 patients) was reported as throbbing 12 (9%), band like 27 (20%), thunderclap 7 (5%), and other (pounding, exploding, stabbing, etc.) 26 (20%). The location of headache (reported in 101 patients) was reported as unilateral (one side of head) 48 (37%), localized (frontal, temporal, occipital, and neck) 25 (19%), and diffuse (whole head) 28 (20%). 43 (32%) patients had normal neurological examination (normal mental status, cranial nerves, motor and sensory examination with down going planters). 93 (68%) patients have abnormal findings on neurological examination including papilledema 29 (15%) patients, altered mental status 38 (19%), and focal neurological deficit 45 (22%) patients. There was no association between headache and presence of hemorrhage on CT and MRI (P = 0.1) or hydrocephalus (P = 0.09). There was no association between localization of headache and site of sinus thrombosis except sigmoid sinus thrombosis, where 17 out of 28 patients with involvement of sigmoid sinus alone or in combination with transverse sinus had pain in the occipital and neck region (P < 0.05). There was no association between lateralization of pain and site of thrombosis (P = 0.66).

Transverse dural sinuses: incidence of anatomical variants and flow artefacts with 2D time-of-flight MR venography at 1 Tesla

PURPOSE

This study sought to identify imaging criteria useful in discriminating anatomical variants from thrombosis of the posterior intracranial venous system.

MATERIALS AND METHODS

A total of 102 patients underwent coronal unenhanced two-dimensional time-of-flight (2D ToF) magnetic resonance (MR) venography. Transverse sinus (TS) calibre and asymmetry were considered. Oval (O-FG) and linear (L-FG) flow gaps were recorded. Several slices of the 2D ToF sequence were applied perpendicularly to the TS within each FG to avoid in-plane saturation.

RESULTS

Mean calibre of the right TS was significantly greater than the contralateral sinus (6.5 mm+/-1.84 vs 5.1 mm+/-1.72). Right and left dominance was observed in 61% and 17% of cases, respectively. The mean right-left TS diameter was 5.77 mm. Among 204 TS, 44 L-FG and 42 O-FG were observed. Partial L-FG (<2/3 of TS) never involved the distal TS. No L-FG was observed in a dominant TS. Supplementary sagittal 2D ToF images disclosed blood flow in all but two L-FGs. O-FGs were mostly observed laterally (91%).

CONCLUSIONS

L-FGs in a dominant TS, partial L-FGs in the distal part or O-FG in the medial part of any TS, a left-right mean diameter <3 mm and absence of flow even in ToF images perpendicular to the direction of blood flow should raise the suspicion of sinus pathology.

Roles of inflammation and the activated protein C pathway in the brain edema associated with cerebral venous sinus thrombosis

BACKGROUND AND PURPOSE

Increased blood-brain barrier (BBB) permeability, brain edema, and hemorrhage are important consequences of cerebral venous sinus thrombosis (CVST). The objective of this study was to define the role of the protein C pathway in the BBB permeability and edema elicited by experimental CVST. The role of neutrophil recruitment was also evaluated.

METHODS

Edema, BBB permeability, leukocyte-endothelial cell adhesion (LECA) and inflammatory cytokine levels were monitored in a murine model of CVST. The role of activated protein C (APC) was assessed in wild type mice (WT) receiving APC neutralizing antibody and in endothelial protein C receptor overexpressing mice (EPCR-tg). Neutrophil involvement was evaluated using an anti-CD18 antibody (Ab) and antineutrophil serum.

RESULTS

Brain edema and increases in BBB permeability and LECA were noted 48 hours after CVST. APC immunoblockade exacerbated these responses, while EPCR-tg exhibited blunted responses, as did WT treated with either antineutrophil serum or the CD18 Ab.

CONCLUSIONS

The protein C pathway protects the brain against the deleterious microvascular responses to CVST, a response that appears to be linked to the recruitment of inflammatory cells.

Traumatic fistula between the middle meningeal artery and the sphenoparietal sinus

PURPOSE

Post-traumatic fistulas between the middle meningeal artery and the cranial venous system are extremely rare. We describe clinical presentation and successful endovascular management of a case of post-traumatic fistula between the middle meningeal artery and the sphenoparietal sinus.

METHODS

A 53-year-old man was admitted with multiple brain contusions and a temporoparietal fracture after a head trauma. On day 3 after trauma he developed unilateral signs of a cavernous sinus syndrome. Digital subtraction angiography showed a fistula between the middle meningeal artery and the sphenoparietal sinus.

RESULTS

The fistula was occluded by endovascular coil embolization, resulting in complete remission of the clinical symptoms.

CONCLUSION

A high index of suspicion is necessary to detect subtle signs of venous congestion of the cavernous sinus in an intubated patient. Angiography is the diagnostic modality of choice and should include the selective investigation of the external carotid artery vascular territory. Endovascular therapy provides minimal invasive and definitive treatment of this rare condition.

A case of mushroom shape temporal bone osteoma

A cranial vault Osteoma is relatively common benign tumor. Mushroom shaped skull osteoma is, however, extremely rare. Twenty seven years old female developed slow growing hard mass posterior to the ear. CT scan revealed a mushroom shaped osseous mass approximately 2.5 cm in diameter protruding from the temporal bone at the site of asterion. And the tumor was located over the right sigmoid sinus. The sigmoid sinus engraved approximately 4mm to the tumor and had a branching to one emissaries' vein. Operation was performed under general anesthesia. The tumor was excised first by cutting the base of the tumor, and then residual tumor was grinded using a round head cutting bar. A chisel dissection was not recommended because of underlining sinus. Histological findings were consistent with a benign osteoma. The postoperative course was uneventful. CT examination immediately done after operation revealed no evidence of intracranial hemorrhage, or injury of vessels. Osetoma was excised, and the surface of cranial bone at the operation site was smooth and cosmetically acceptable. At 6-months follow up, patient remains asymptomatic and recurrence free. CT examination with Multi Planer Reconstruction imaging or 3D reconstruction is highly recommended for the operational planning of cranial osteoma.

[Incidence of venous system disease in pseudotumor cerebri]

OBJECTIVE

Pseudotumor cerebri (PC) is a complex syndrome characterized by increased intracranial pressure in the absence of any space occupying lesion, usually self-limiting, but often relapsing In recent years, some authors had researched the relationship between venous sinus disease and PC and they have suggested that it must be ruled out by magnetic resonance venography (MRV) before diagnosing this condition as idiopathic. Our aim is to determine the frequency of venous sinus disease and the need for MRV in these patients.

METHODS

We have studied 14 patients admitted between 1998 and 2005 in the Neurology Department of the University Clinical Hospital <<Lozano Blesa>> (Zaragoza; Spain) who had been diagnosed of PC. We reviewed the epidemiological and clinical features. The MRVs were reviewed and their appearances rated for focal narrowing and signal gaps.

RESULTS

Six patients had strong signal in both lateral and transverse sinus and their image was considered as normal. The other eight patients showed filling defects on the transverse sinus (focal unilateral narrowing in four cases, one or more signal gaps in four cases).

CONCLUSIONS

The presence of signal gaps in the venous sinus (stenosis/hypoplasia or absence of signal) is a frequent finding in patients with PC. That is why we have concluded that this test is important in patients with PC in order to search for a possible etiology and treatment option.

Duplication of falx cerebelli, occipital sinus, and internal occipital crest

The incidence of variations of falx cerebelli was studied in 52 adult cadavers of south Indian origin, at Kasturba Medical College Mangalore, after removal of calvaria. In eight (15.4%) cases, we observed duplicated falx cerebelli along with duplicated occipital sinus and internal occipital crest. The length and the distance between each of the falces were measured. The mean length of the right falces cerebelli was 38 mm and the left was 41 mm. The mean distance between these two falces was 20 mm. No marginal sinus was detected. Each of the falces cerebelli had distinct base and apex and possessed a distinct occipital venous sinus on each attached border. These sinuses were noted to drain into the left and right transverse sinus respectively. After detaching the dura mater from inner bony surface of the occipital bone, it was noted that there were two distinct internal occipital crests arising and diverging inferiorly near the posterolateral borders of foramen magnum. The brain from these cadavers appeared grossly normal with no defect of the vermis. Neurosurgeons and neuroradiologists should be aware of such variations, as these could be potential sources of hemorrhage during suboccipital approaches or may lead to erroneous interpretations of imaging of the posterior cranial fossa.

Expression of angiogenic growth factor in the rat DAVF model

OBJECTIVE

The precise mechanisms responsible for the development and growth of dural arteriovenous fistula (DAVF) remain unclear, but it has been hypothesized that vascular endothelial growth factor (VEGF) might be involved in the pathogenesis. The aim of this study was to examine the expression of VEGF in the rat DAVF model.

METHODS

Forty-five Sprague-Dawley rats were used in two experiments. In Experiment 1 (n = 20, including sham-operated controls), VEGF expression was analysed by Western blots in three different rat DAVF models: model I: common carotid artery-external jugular vein (CCA-EJV) anastomosis (n = 5); model II: sagittal sinus thrombosis and bipolar coagulation of the vein draining the transverse sinus (n = 5); model III: CCA-EJV anastomosis and bipolar coagulation of the vein draining the transverse sinus and sagittal sinus thrombosis to induce venous hypertension (n = 5). Based on the results of Experiment 1, Western blots were performed at weekly intervals 1, 2 and 3 weeks in Experiment 2 following induction of venous hypertension in model III (n = 5 at each time point and n = 5 sham controls); in addition, VEGF expression was immunohistochemically examined in the dura and the brain near the occluded sinus in five model III animals after 1 week.

RESULTS

In Experiment 1, Western blot analysis showed barely detectable bands with molecular weights of 45 kD, corresponding to VEGF, in the sham group, but the highest level of VEGF was induced in model III, followed by models I and II (model III>model I>model II). In Experiment 2, the expression of VEGF peaked 1 week after induction of venous hypertension in model III, decreasing in a linear fashion over 2 and 3 weeks (week 1>weeks 2 and 3). The expression of immunoreactive VEGF was restricted in the connective tissue and the endothelial layer of the dura matter, cerebral cortical tissue and neurons of the basal ganglia.

CONCLUSION

Our results strongly suggest a possible contribution of an angiogenic factor to the growth of DAVF. Venous ischemia by venous hypertension might be a mechanism for inducing up-regulation of angiogenic factor expression.

Fibrous dysplasia of the temporal bone complicated by cholesteatoma and thrombophlebitis of the transverse and sigmoid sinuses: a case report

Fibrous dysplasia is a benign condition that can affect the skull and facial bones and cause a broad spectrum of otolaryngologic conditions. We present the case of a boy with polyostotic fibrous dysplasia with involvement of the temporal bone that was first diagnosed when he was 9 years old. His condition eventually became complicated by cholesteatoma and thrombophlebitis of the left transverse and sigmoid sinuses, and he died of his disease at the age of 19 years. We discuss these and other complications of fibrous dysplasia of the temporal bone and their management.

A case of neonatal dural sinus malformation: clinical symptoms, imaging and neuropathological investigations

We report a case of neonatal dural sinus malformation already visible on antenatal ultrasound. This is a rare disease entity in infants and children. Clinical diagnosis was made by demonstrating a cranial murmur on auscultation; macrocrania and signs of progressive cardiac failure. Imaging studies as cerebral ultrasound, postnatal MRI scan and MR angiography demonstrated a large dural sinus malformation originating from the sagittal sinus with extensive arteriovenous fistulae. Due to the extent of the lesion, the existing ischemic brain damage and involvement of the torcular, no therapeutic options were available and the child died of irreversible cardiac failure. The diagnosis was confirmed with autopsy. We discuss the clinical presentation, imaging and neuropathological results and relate our findings to embryological data and the existing literature.

Cerebral sinovenous thrombosis in children

Sinovenous thrombosis in children is rare, and the symptoms and signs are nonspecific especially in the neonatal population. MR imaging seems to be the most sensitive for accurate diagnosis of dural sinus thrombosis. General medical and neurologic supportive care is the mainstay of treatment. However, more active medical treatment such as anticoagulation, as well as an aggressive form of treatment such as retrograde transvenous fibrinolytic therapy, in children whose condition declines despite adequate anticoagulation therapy can be justified.