Internal jugular vein fistula mimicking dural arteriovenous fistula after cardiac pacemaker placement.

Carotid jugular arteriovenous fistulas are a documented complication of cannulation of the internal jugular vein. They may present with neck pain, headache, and cardiovascular aberrations. However, carotid jugular fistula secondary thrombus formation after jugular cannulation with radiographic presentation similar to dural arteriovenous fistula has not yet been reported in the literature. Below, we report the case of a 68-year-old male with an incidentally found carotid-jugular fistula secondary to pacemaker placement who had intracranial reflux on imaging, which was ultimately treated successfully through an endovascular approach.

Eagle syndrome causing cerebral sinus hypertension: Case report.

Eagle Syndrome is a rare condition with a variety of presentations, resulting from an enlarged styloid process or calcified stylohyoid ligament. Due to the variety of presentations, diagnosis can be difficult. In this report, we present a case of ES that presented with a constellation of neurological symptoms, including headache and visual disturbance, ultimately found to be due to cerebral sinus hypertension, exacerbated by certain movements, caused by an enlarged styloid process with calcification of the stylohyoid ligament, consistent with ES. The patient underwent styloidectomy with immediate resolution of symptoms. This case report illustrates the diagnostic quandary often posed by ES and hopes to add further understanding to its presentation and diagnosis.

Cone Beam CT With Flat Panel Detector and Biplane Fluoroscopy-Guided Percutaneous Trigeminal Nerve Rhizotomy Using Three-Dimensional Needle Trajectory Planning.

Trigeminal-mediated pain disorders can be devastating for patients refractory to medical therapy. Gasserian ganglion blocks and percutaneous trigeminal rhizotomy have been used with success to treat these patients, however, serious complication risks include facial hematoma, cranial nerve palsy, and stroke. Cone beam CT, combined with fluoroscopy and needle navigation has been shown to decrease needle pass rates, procedure time, radiation exposure, and complications in multiple interventional radiology procedures, but hitherto has not been utilized for Gasserian ganglion interventions. Here, we present two cases of trigeminal-mediated pain successfully treated via cone beam CT combined fluoroscopy and needle navigation.

Intra-arterial Bevacizumab for Posterior Fossa Hemangioblastoma.

Hemangioblastoma (HB) is a rare, highly vascularized, and benign central nervous system (CNS) tumor. This vascularity is due to a high degree of signaling by vascular endothelial growth factor (VEGF). Consequently, anti-VEGF agents, such as bevacizumab, have been postulated and shown in a few cases to be effective in treating these tumors when surgical therapy is not feasible. Additionally, selective intra-arterial (IA) administration of bevacizumab has shown promise in treating other cancers such as glioblastoma (GBM). Here, we present the case of a 60-year-old female with a symptomatic posterior fossa HB where embolization and surgery were not feasible due to tumor location. She underwent selective IA treatment with bevacizumab, which led to tumor stability and symptomatic improvement. Bevacizumab has been used intravenously (IV) as a treatment for HB, however, its efficacy has not been well-established. This case demonstrates the potential viability of selective bevacizumab in HB, as demonstrated by symptomatic improvement and decreased tumor size on MRI. Further research is needed to demonstrate the specific efficacy of IA bevacizumab for CNS HB when surgery or other treatment modalities are not viable options.

Iatrogenic Spinal Epidural Hematoma Associated with Intracranial Hypotension.

Epidural steroid injections (ESIs) are one of the few modalities currently in use for treating chronic spinal pain. There are two approaches: interlaminar ESIs and transforaminal ESIs. Complications arising from either approach are rare, but one such complication is cerebrospinal fluid (CSF) leak leading to intracranial hypotension. Even rarer is the development of iatrogenic spinal epidural hematoma in the context of the injections. Interestingly, an association with intracranial hypotension and spinal epidural hematoma has yet to be established. Even the characteristics of an iatrogenic spinal epidural hematoma are not well defined as there are different theories of how this develops and whether we are dealing with arterial or venous blood. Our case is unique as it appears our patient had developed not one, but both clinical symptoms supportive of intracranial hypotension from a CSF leak induced iatrogenically from a cervical epidural injection and imaging demonstrated thoracic-level spinal epidural hematoma. It is unclear whether the injection directly led to the spinal leak causing the intracranial hypotension, which then brought on the formation of the hematoma or if the injection led to both intracranial hypotension and hematoma formation independent of each other. From a clinical practice standpoint, given our case suggests the hematoma was concomitantly associated with intracranial hypotension, and the possibility exists that the hematoma may have formed in the context of the intracranial hypotension, then targeted blood patches may need to be done with greater urgency to preventing hematoma formation. Further studies are needed involving clotting factors comparing arterial and venous blood. It is also puzzling why the epidural blood from the hematoma did not clot the leak. This concomitancy deserves further attention and may lead to changes in how we manage cervical epidural injection patients who are found to have CSF leak and a spinal epidural hematoma.

Dural Arteriovenous Fistula Associated With a Vestibular Tumor: An Unusual Case and Review of the Literature.

Intracranial dural arteriovenous fistulae (DAVF) are rare vascular malformations. They are generally considered to be acquired lesions, often attributed to dural sinus thrombosis and intracranial venous hypertension. The authors encountered a case of DAVF associated with an octreotide-positive vestibular schwannoma. A 46-year-old female had symptoms of right ear congestion accompanied by pulsatile tinnitus and mild hearing loss. Magnetic resonance imaging (MRI) identified a lobulated mass centered at the cerebellopontine angle. Preoperatively, on cerebral angiography, there was an incidental discovery of a DAVF in the right posterior fossa. The decision was made to proceed with resection of the tumor in a staged fashion. Her latest follow-up MRI showed no evidence of recurrent tumor. This is the second reported case of DAVF associated with an intracranial schwannoma. Findings are discussed along with a thorough review of the literature. This case, combined with the data from the literature review, led us to believe that tumor-related angiogenesis might contribute to DAVF formation.

Loading and elution characteristics of quadrasphere microspheres loaded with bevacizumab.

AIM: Super absorbent polyvinyl alcohol-sodium acrylate copolymer microspheres, Quadrasphere microspheres (QSM), are commonly used for drug-eluting bead therapy, however, the literature only reports its use with small molecule chemotherapeutics. This study evaluates the loading and elution characteristics of bevacizumab-loaded QSM. METHODS & RESULTS: A single vial of QSM was reconstituted with 200 mg of bevacizumab. Drug concentration was determined by ELISA immunoassay. At approximately 90 min, there was maximal loading at 59% of the starting dose. In vitro elution demonstrated 52% of bound bevacizumab was released within the first hour and 68% by 16 h. CONCLUSION: Bevacizumab can load onto QSM and elute over time. This targeted delivery vehicle may potentially result in more effective treatment and fewer complications related to systemic toxicity.

Big Data and the Future of Radiology Informatics.

Rapid growth in the amount of data that is electronically recorded as part of routine clinical operations has generated great interest in the use of Big Data methodologies to address clinical and research questions. These methods can efficiently analyze and deliver insights from high-volume, high-variety, and high-growth rate datasets generated across the continuum of care, thereby forgoing the time, cost, and effort of more focused and controlled hypothesis-driven research. By virtue of an existing robust information technology infrastructure and years of archived digital data, radiology departments are particularly well positioned to take advantage of emerging Big Data techniques. In this review, we describe four areas in which Big Data is poised to have an immediate impact on radiology practice, research, and operations. In addition, we provide an overview of the Big Data adoption cycle and describe how academic radiology departments can promote Big Data development.

Intermittent enhancement in chronic nodular calcified neurocysticercosis.

Neurocysticercosis (NCC) is the most common cause of new onset seizures and epilepsy in the developing and tropical world. There has been a marked increase in domestic cases of diseases traditionally associated with developing countries, and now NCC should be high on a radiologist's differential diagnosis list for a patient with seizures. Radiologic findings of NCC correlate with the parasite's life cycle within the host. The calcified granulomas signify the final stage (nodular calcified) as nonenhancing punctate calcifications on imaging and are traditionally known to remain without enhancement. Here we describe a unique case of intermittent enhancement of a cortical calcified nodule secondary to NCC that was followed for over 10 years. Radiologists must challenge the traditionally accepted progression of imaging findings and accept that calcified nodules of chronic NCC may intermittently enhance.

Low-dose cardiotonic steroids increase sodium-potassium ATPase activity that protects hippocampal slice cultures from experimental ischemia.

The sodium-potassium ATPase (Na/K ATPase) is a major ionic transporter in the brain and is responsible for the maintenance of the Na(+) and K(+) gradients across the cell membrane. Cardiotonic steroids such as ouabain, digoxin and marinobufagenin are well-characterized inhibitors of the Na/K ATPase. Recently, cardiotonic steroids have been shown to have additional effects at concentrations below their IC(50) for pumping. The cardiotonic steroids ouabain, digoxin, and marinobufagenin all show an inverted U-shaped dose-response curve with inhibition of pumping at concentrations near their IC(50), while increasing Na/K ATPase activity at doses below their IC(50). This stimulatory effect of cardiotonic steroids was observed in vitro in hippocampal slice cultures as well as in the hippocampus in vivo. Increased Na/K ATPase activity has been shown to protect slice culture neurons from hypoxia-hypoglycemia. Ouabain protected slice culture neurons from experimental ischemia at concentrations that increased Na/K ATPase. This protective effect was observed when ouabain was dosed 30min before, or 2h following experimental ischemia. Ouabain no longer protected against experimental ischemia if the increase of Na/K ATPase was blocked. These data suggest that the protective effect of ouabain was due to increased Na/K ATPase activity. The demonstration of a neuroprotective effect of cardiotonic steroids could potentially assist in the treatment of stroke since digoxin, one of the cardiotonic steroids examined in this study, has approval by the Food and Drug Administration and can be safely administered at the concentrations that increase Na/K ATPase activity.

Conditional deletion of the NMDA-NR1 receptor subunit gene in the central nucleus of the amygdala inhibits naloxone-induced conditioned place aversion in morphine-dependent mice.

Preclinical behavioral pharmacological and neuropharmacological evidence indicates that the NMDA receptor plays an important role in opioid dependence, however, the neural substrates subserving these actions are poorly understood. The central nucleus of the amygdala (CeA) is a critical coordinator of autonomic, behavioral, and emotional systems impacted by opioids, however there is no evidence that the essential NMDA-NR1 (NR1) subunit gene in the amygdala plays a role in opioid dependence. To determine the role of the NR1 subunit gene in the amygdala with respect to physical and psychological opioid withdrawal, a spatial-temporal deletion of this gene was produced by microinjecting a recombinant adeno-associated virus (rAAV) expressing the GFP reporter and Cre recombinase (rAAV-GFP-Cre) into the CeA of adult "floxed" NR1 mice (fNR1). Amygdala microinjection of rAAV-GFP-Cre produced a decrease in NR1 gene expression and protein immunolabeling in postsynaptic sites of neurons without signs of compromised ultrastructural neuronal morphology. Amygdala NR1 gene deletion also did not affect locomotor, somatosensory, or sensory-motor behaviors. In addition, bilateral local NR1 gene deletion did not impact somatic or visceral withdrawal symptoms precipitated by naloxone in morphine-dependent mice. However, there was a significant deficit in the expression of an opioid withdrawal-induced conditioned place aversion in mice with amygdala NR1 deletion. These results indicate that functional amygdala NMDA receptors are involved in aversive psychological processes associated with opioid withdrawal. More generally, spatial-temporal deletion of the NR1 subunit by Cre-loxP technology is an effective means to elucidate the neurogenetic substrates of complex phenotypes associated with drug abuse.

Changes in the subcellular distribution of NADPH oxidase subunit p47phox in dendrites of rat dorsomedial nucleus tractus solitarius neurons in response to chronic administration of hypertensive agents.

NADPH oxidase-generated superoxide can modulate crucial intracellular signaling cascades in neurons of the nucleus tractus solitarius (NTS), a brain region that plays an important role in cardiovascular processes. Modulation of NTS signaling by superoxide may be linked to the subcellular location of the mobile NADPH oxidase p47(phox) subunit, which is known to be present in dendrites of NTS neurons. It is not known, however, if hypertension can produce changes in the trafficking of p47(phox) in defined NTS subregions, particularly the preferentially barosensitive dorsomedial NTS (dmNTS), or preferentially gastrointestinal medial NTS (mNTS). We used immunogold electron microscopy to determine if p47(phox) localization was differentially affected in dendritic profiles of neurons from these NTS subregions of the rat in response to distinct models of hypertension, namely chronic 7-day subcutaneous administration of angiotensin II (AngII), or phenylephrine. In small (<1 microm) dendritic processes, both AngII and phenylephrine produced a decrease in intracellular p47(phox) labeling selectively in dmNTS neurons. In intermediate-size (1-2 microm) dendritic profiles in the dmNTS region only, there was an increase in p47(phox) labeling in response to each hypertensive agent, although these changes occurred in different subcellular compartments. There was an increase in non-vesicular labeling in response to AngII, but an increase in surface labeling with phenylephrine. Moreover, each of the changes in p47(phox) targeting mentioned above occurred in dendritic profiles with, or without immunoperoxidase labeling for the AngII AT-1A receptor subtype (AT-1A). These results indicate that chronic administration of agents that induce hypertension can also produce changes in the subcellular localization in p47(phox) in dmNTS neurons. Thus, systemic hypertension may produce alterations in the trafficking of proteins associated with superoxide production in central autonomic neurons, thus revealing a potentially important neurogenic component of free radical production and systemic blood pressure elevation.