Bilateral Simultaneous Magnetic Resonance-Guided Focused Ultrasound Pallidotomy for Life-Threatening Status Dystonicus

BACKGROUND

Invasive treatments like radiofrequency stereotactic lesioning or deep brain stimulation of the globus pallidus internus can resolve drug-resistant status dystonicus (SD). However, these open procedures are not always feasible in patients with SD.

OBJECTIVE

The aim was to report the safety and efficacy of simultaneous asleep bilateral transcranial magnetic resonance-guided focused ultrasound (MRgFUS) pallidotomy for life-threatening SD.

METHODS

We performed bilateral simultaneous MRgFUS pallidotomy under general anesthesia in 2 young patients with pantothenate kinase-associated neurodegeneration and GNAO1 encephalopathy. Both patients had medically refractory SD and severe comorbidities contraindicating open surgery.

RESULTS

SD resolved at 4 and 12 days after MRgFUS, respectively. Adverse events (intraoperative hypothermia and postoperative facial paralysis) were mild and transient.

CONCLUSION

Bilateral simultaneous MRgFUS pallidotomy under general anesthesia is safe and may be a valid alternative therapeutic option for fragile patients. Further studies are needed to assess long-term efficacy of the procedure. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Considering Psychological and Cognitive Factors in Interventional Neuroradiology: A Systematic Literature Review

BACKGROUND

Interventional neuroradiology is a relatively recent discipline that diagnoses and treats cerebral vascular diseases. However, specific literature on cognitive and psychological domains of patients undergoing interventional neuroradiology procedures is limited.

PURPOSE

Our aim was to review the existent literature on cognitive and psychological domains in patients undergoing interventional neuroradiology procedures to raise clinicians' awareness of their mental status.

DATA SOURCES

Articles were searched in PubMed, EMBASE, and Scopus from 2000 to 2022 using terms such as "interventional neuroradiology," "psychology," and "cognition" according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

STUDY SELECTION

Of 1483 articles in English, 64 were included and analyzed. Twelve focused on psychological aspects; 52, on cognitive ones.

DATA ANALYSIS

Regarding psychological aspects, it appears that early psychological consultations and "nonpharmacologic" strategies can impact the anxiety and depression of patients undergoing endovascular procedures. Regarding cognitive aspects, it appears that endovascular treatment is safe and generates similar or even fewer cognitive deficits compared with analogous surgical procedures.

DATA SYNTHESIS

Among the 12 articles on psychological aspects, 6/12 were retrospective with one, while 6/12 were prospective. Among the 52 articles on cognitive aspects, 7/54 were retrospective, while 45/52 were prospective.

LIMITATIONS

The main limitation derives from the inhomogeneity of the cognitive and psychological assessment tools used in the articles included in our analysis.

CONCLUSIONS

Our review highlights the need to include cognitive and psychological assessments in clinical practice in case patients eligible for interventional neuroradiology procedures. In the future, much more research of and attention to cognitive and psychologic aspects of neurovascular disease is needed. Systematic incorporation of strategies and tools to access and address pre, peri-, and postprocedural psychological and cognitive components could have major benefits in patient satisfaction, recovery, and the success of endovascular practice.

Neuroimaging Modalities Used for Ischemic Stroke Diagnosis and Monitoring

Strokes are one of the global leading causes of physical or mental impairment and fatality, classified into hemorrhagic and ischemic strokes. Ischemic strokes happen when a thrombus blocks or plugs an artery and interrupts or reduces blood supply to the brain tissue. Deciding on the imaging modality which will be used for stroke detection depends on the expertise and availability of staff and the infrastructure of hospitals. Magnetic resonance imaging provides valuable information, and its sensitivity for smaller infarcts is greater, while computed tomography is more extensively used, since it can promptly exclude acute cerebral hemorrhages and is more favorable speed-wise. The aim of this article was to give information about the neuroimaging modalities used for the diagnosis and monitoring of ischemic strokes. We reviewed the available literature and presented the use of computed tomography, CT angiography, CT perfusion, magnetic resonance imaging, MR angiography and MR perfusion for the detection of ischemic strokes and their monitoring in different phases of stroke development.

Watch brain circulation in unexplained progressive myelopathy: a review of Cognard type V arterio-venous fistulas

BACKGROUND

Intracranial dural arterio-venous fistulas are pathological anastomoses between arteries and veins located within dural sheets and whose clinical manifestations depend on location and hemodynamic features. They can sometimes display perimedullary venous drainage (Cognard type V fistulas-CVFs) and present as a progressive myelopathy. Our review aims at describing CVFs' variety of clinical presentation, investigating a possible association between diagnostic delay and outcome and assessing whether there is a correlation between clinical and/or radiological signs and clinical outcomes.

METHODS

We conducted a systematic search on Pubmed, looking for articles describing patients with CVFs complicated with myelopathy.

RESULTS

A total of 72 articles for an overall of 100 patients were selected. The mean age was 56.20 ± 14.07, 72% of patients were man, and 58% received an initial misdiagnosis. CVFs showed a progressive onset in 65% of cases, beginning with motor symptoms in 79% of cases. As for the MRI, 81% presented spinal flow voids. The median time from symptoms' onset to diagnosis was 5 months with longer delays for patients experiencing worse outcomes. Finally, 67.1% of patients showed poor outcomes while the remaining 32.9% obtained a partial-to-full recovery.

CONCLUSIONS

We confirmed CVFs' broad clinical spectrum of presentation and found that the outcome is not associated with the severity of the clinical picture at onset, but it has a negative correlation with the length of diagnostic delay. We furthermore underlined the importance of cervico-dorsal perimedullary T1/T2 flow voids as a reliable MRI parameter to orient the diagnosis and distinguish CVFs from most of their mimics.

Case 310: Posterior Epidural Migration of a Lumbar Disk Herniation

HISTORY

A 49-year-old man presented with right foot drop, bilateral cruralgia mainly on the left side, and genital and perianal hypoesthesia, which started suddenly 12 days before. After onset of symptoms, the patient also experienced an accidental fall at home, resulting in a left fibular fracture, which was treated with reduction and with seven-hole plate Synthes Locking Compression Plate at the orthopedic clinic. The neurologic examination showed paresthesias on the posterior aspect of both thighs and crural regions that was worse on the left side, hypoesthesia in the L5 root region on the right side, and right foot drop. There was no urinary retention or fecal incontinence. The patient denied past surgery, back trauma, heavy manual labor, hypermobility, or any other remarkable medical history. The patient was afebrile. Laboratory results on the 1st day of hospitalization showed increased C-reactive protein level (0.62 mg/dL; reference range, 0.0-0.5 mg/dL), elevated erythrocyte sedimentation rate (60 mm/h; reference range, 0-20 mm/h), and increased aspartate transaminase (38 U/L [0.63 μkat/L]; reference range, 0-31 U/L [0-0.52 μkat/L]), alanine transaminase (70 U/L [1.17 μkat/L]; reference range, 0-31 U/L [0-0.52 μkat/L]), and high lymphocyte (4.55 × 103/mL; reference range, [1.0-3.0] ×103/mL), and neutrophil (8.79 × 103/mL; reference range, [2.0-7.0] × 103/mL) levels. Absence of coagulopathy was demonstrated by normal coagulation values (international normalized ratio, 1.19; reference value, 0.80-1.25; activated partial thromboplastin time ratio, 0.88 second; reference range, 0.79-1.27 seconds). Electroneurography showed marked hypoevocable F response in the right tibia. Electromyography indicated severe reduction of muscle recruitment pertaining to right L4, L5, and S1 nerve territory and, to a lesser extent, of muscles pertaining to L3 territory bilaterally in the absence of spontaneous denervation. Unenhanced CT and contrast-enhanced MRI of the lumbosacral spine were performed.

The Role of Bypass Surgery for the Management of Complex Intracranial Aneurysms in the Anterior Circulation in the Flow-Diverter Era: A Single-Center Series

Despite the increasing popularity of flow diverters (FDs) as an endovascular option for intracranial aneurysms, the treatment of complex aneurysms still represents a challenge. Combined strategies using a flow-preservation bypass could be considered in selected cases. In this study, we retrospectively reviewed our series of patients with complex intracranial aneurysms submitted to bypass. From January 2015 to May 2022, 23 patients were selected. We identified 11 cases (47.8%) of MCA, 6 cases (26.1%) of ACA and 6 cases (26.1%) of ICA aneurysms. The mean maximal diameter was 22.73 ± 12.16 mm, 8 were considered as giant, 9 were fusiform, 8 presented intraluminal thrombosis, 10 presented wall calcification, and 18 involved major branches or perforating arteries. Twenty-five bypass procedures were performed in 23 patients (two EC–IC bypasses with radial artery graft, seventeen single- or double-barrel STA–MCA bypasses and six IC–IC bypasses in anterior cerebral arteries). The long-term bypass patency rate was 94.5%, and the total aneurysm exclusion was 95.6%, with a mean follow-up of 28 months. Median KPS values at last follow-up was 90, and a favorable outcome (KPS ≥ 70 and mRS ≤ 2) was obtained in 87% of the cases. The use of bypass techniques represents, in selected cases, a valid therapeutic option in the management of complex anterior circulation aneurysms when a simpler direct approach, including the use of FD, is considered not feasible.

Case 310

HISTORY

A 49-year-old man presented with right foot drop, bilateral cruralgia mainly on the left side, and genital and perianal hypoesthesia, which started suddenly 12 days before. After onset of symptoms, the patient also experienced an accidental fall at home, resulting in a left fibular fracture, which was treated with reduction and with seven-hole plate Synthes Locking Compression Plate at the orthopedic clinic. The neurologic examination showed paresthesias on the posterior aspect of both thighs and crural regions that was worse on the left side, hypoesthesia in the L5 root region on the right side, and right foot drop. There was no urinary retention or fecal incontinence. The patient denied past surgery, back trauma, heavy manual labor, hypermobility, or any other remarkable medical history. The patient was afebrile. Laboratory results on the 1st day of hospitalization showed increased C-reactive protein level (0.62 mg/dL; reference range, 0.0-0.5 mg/dL), elevated erythrocyte sedimentation rate (60 mm/h; reference range, 0-20 mm/h), and increased aspartate transaminase (38 U/L [0.63 μkat/L]; reference range, 0-31 U/L [0-0.52 μkat/L]), alanine transaminase (70 U/L [1.17 μkat/L]; reference range, 0-31 U/L [0-0.52 μkat/L]), and high lymphocyte (4.55 × 10³/μL; reference range, [1.0-3.0] × 10³/μL), and neutrophil (8.79 × 10³/μL; reference range, [2.0-7.0] × 10³/μL) levels. Absence of coagulopathy was demonstrated by normal coagulation values (international normalized ratio, 1.19; reference value, 0.80-1.25; activated partial thromboplastin time ratio, 0.88 second; reference range, 0.79-1.27 seconds). Electroneurography showed marked hypoevocable F response in the right tibia. Electromyography indicated severe reduction of muscle recruitment pertaining to right L4, L5, and S1 nerve territory and, to a lesser extent, of muscles pertaining to L3 territory bilaterally in the absence of spontaneous denervation. Unenhanced CT (Fig 1) and contrast-enhanced MRI of the lumbosacral spine were performed (Figs 2, 3).

Coating (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) study. The first randomized controlled trial evaluating a coated flow diverter (p64 MW HPC): study design

BACKGROUND

Due to its high efficacy, flow diversion is increasingly used in the management of unruptured and recanalized aneurysms. Because of the need for perioperative dual antiplatelet treatment (DAPT), flow diversion is not indicated for the treatment of ruptured aneurysms. To overcome this major limitation, surface modification-'coating'-of flow diverters has been developed to reduce platelet aggregation on the implanted device, reduce thromboembolic complications, and facilitate the use of coated flow diverter treatment in patients with single antiplatelet treatment (SAPT). COATING (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) is a prospective, randomized, multicenter trial that aims to determine whether the use of the coated flow diverter p64 MW HPC under SAPT is non-inferior (or even superior) to the use of the bare flow diverter p64 MW under DAPT in relation to thromboembolic and hemorrhagic complications.

METHODS

Patients with unruptured or recanalized aneurysms for which endovascular treatment with a flow diverter is indicated will be enrolled and randomly assigned on a 1:1 ratio to one of two treatment groups: p64 MW HPC with SAPT or p64 MW with DAPT.

RESULTS

The primary endpoint is the number of diffusion-weighted imaging lesions visualized via MRI assessed within 48 hours (±24 hours) of the index procedure. Secondary primary endpoints are comparing safety and efficacy in both arms.

CONCLUSIONS

This randomized controlled trial is the first to directly compare safety and efficacy of coated flow diverters under SAPT with bare flow diverters under DAPT.

TRIAL REGISTRATION NUMBER

http://clinicaltrials.gov/ - NCT04870047.

The Pre-Lumbar puncture Intracranial Hypertension Scale (PLIHS): A practical scale to identify subjects with normal cerebrospinal fluid pressure in the management of idiopathic intracranial hypertension

BACKGROUND

Idiopathic Intracranial Hypertension (IIH) diagnosis requires lumbar puncture to measure cerebrospinal fluid (CSF) pressure. The Pre-Lumbar puncture Intracranial Hypertension Scale (PLIHS) is aimed to detect cases that will show raised or normal CSF opening pressure.

METHODS

Retrospective analysis of records of patients who underwent lumbar puncture for suspect IIH. The target was CSF opening pressure ≥ 250 mmH2O, whereas a set of known neurological, neuro-ophthalmological and neuro-radiological parameters, plus obesity, were used as predictors in a logistic regression model. The PLIHS was based on significant predictors and a cut-off was validated using chi-squared test around CSF opening pressure ≥ 250 and < 200 mmH2O.

RESULTS

Records of 162 patients were included: CSF opening pressure was <200 mmH2O in 40 and ≥ 250 mmH2O in 95 patients; 85 fulfilled IIH diagnosis. PLIHS is based on Frisén grade 2 or higher papilledema, tinnitus, empty sella, perioptic subarachnoid space distension, and obesity. Score range is 0-7: correlation with CSF opening pressure is 0.508 (p < .001), and PLIHS score is different between subjects not diagnosed with IIH, and those diagnosed with IIH both with and without papilledema (p < .001). PLIHS score ≤ 2 identifies cerebrospinal fluid pressure < 200 mmH2O; PLIHS score ≥ 3 identifies CSF opening pressure ≥ 250 mmH2O, IIH diagnosis, visual acuity ≤0.7, and optic nerve atrophy.

CONCLUSIONS

The PLIHS, can be used to identify patients who will particularly need LP, thus helping with the organization of the diagnostic work-up by optimising healthcare resources and potentially limit the likelihood to incur in LP-related adverse events.

Long-term follow-up of the Derivo® Embolization Device (DED®) for intracranial aneurysms: the Italian Multicentric Registry

BACKGROUND

The flow-diverter devices (FDDs) safety and effectiveness have been demonstrated by large series and meta-analyses. Due to the high occlusion rates and the acceptable morbidity rates of FDDs, the indications for their use are continuously expanding. We presented our Italian multicentric experience using the second generation of DERIVO® Embolization Device (DED^®; Acandis, Pforzheim, Germany) to cure cerebral aneurysms, evaluating both middle and long-term safety and efficacy of this device.

METHODS

Between July 2016 and September 2017 we collected 109 consecutive aneurysms in 108 patients treated using DED^® during 109 endovascular procedures in 34 Italian centers (100/109 aneurysms were unruptured, 9/109 were ruptured). The collected data included patient demographics, aneurysm location and characteristics, baseline angiography, adverse event and serious adverse event information, morbidity and mortality rates, and pre- and post-treatment modified Rankin Scale scores. Midterm and long-term clinical, angiographic and cross-sectional CT/MR follow-up were recorded and collected until December 2018.

RESULTS

In 2/109 cases, DED^® placement was classified as technical failures. The overall mortality and morbidity rates were respectively 6.5% and 5.5%. Overall DERIVO® related mortality and morbidity rates were respectively 0% and 4.6% (5 out of 108 patients). Midterm neuroimaging follow-up showed the complete or nearly complete occlusion of the aneurysm in 90% cases, which became 93% at long-term follow-up. Aneurysmal sac shrinking was observed in 65% of assessable aneurysms.

CONCLUSIONS

Our multicentric experience using DED^® for endovascular treatment of unruptured and ruptured aneurysms showed a high safety and efficacy profile, substantially equivalent or better compared to the other FDDs.

Endovascular Thrombectomy for Acute Ischemic Stroke Beyond 6 Hours From Onset

Background and Purpose:

To evaluate outcome and safety of endovascular treatment beyond 6 hours of onset of ischemic stroke due to large vessel occlusion in the anterior circulation, in routine clinical practice.

Methods:

From the Italian Registry of Endovascular Thrombectomy, we extracted clinical and outcome data of patients treated for stroke of known onset beyond 6 hours. Additional inclusion criteria were prestroke modified Rankin Scale score ≤2 and ASPECTS score ≥6. Patients were selected on individual basis by a combination of CT perfusion mismatch (difference between total hypoperfusion and infarct core sizes) and CT collateral score. The primary outcome measure was the score on modified Rankin Scale at 90 days. Safety outcomes were 90-day mortality and the occurrence of symptomatic intracranial hemorrhage. Data were compared with those from patients treated within 6 hours.

Results:

Out of 3057 patients, 327 were treated beyond 6 hours. Their mean age was 66.8±14.9 years, the median baseline National Institutes of Health Stroke Scale 16, and the median onset to groin puncture time 430 minutes. The most frequent site of occlusion was middle cerebral artery (45.1%). Functional independence (90-day modified Rankin Scale score, 0–2) was achieved by 41.3% of cases. Symptomatic intracranial hemorrhage occurred in 6.7% of patients, and 3-month case fatality rate was 17.1%. The probability of surviving with modified Rankin Scale score, 0–2 (odds ratio, 0.58 [95% CI, 0.43–0.77]) was significantly lower in patients treated beyond 6 hours as compared with patients treated earlier No differences were found regarding recanalization rates and safety outcomes between patients treated within and beyond 6 hours. There were no differences in outcome between people treated 6-12 hours from onset (278 patients) and those treated 12 to 24 hours from onset (49 patients).

Conclusions:

This real-world study suggests that in patients with large vessel occlusion selected on the basis of CT perfusion and collateral circulation assessment, endovascular treatment beyond 6 hours is feasible and safe with no increase in symptomatic intracranial hemorrhage.

Magnetic resonance diffusion-tensor imaging metrics in High Grade Gliomas: Correlation with IDH1 gene status in WHO 2016 era

PURPOSE

To evaluate any possible correlation between the presence of Isocitrate DeHydrogenase 1 mutation (IDH1m) and specific DTI (Diffusion Tensor Imaging) metrics, such as Fractional Anisotropy (FA), Mean Diffusivity (MD), Radial Diffusivity (RD) and Axial Diffusivity (AD).

METHODS

We retrospectively analyzed 47 patients who underwent an advanced-MR study with DTI followed by surgical intervention with a subsequent histologic diagnosis of High-Grade Glioma (HGG) and immunohistochemical evaluation of IDH1 (Isocitrate DeHydrogenase) mutation status. For each DTI metrics we measured the ratio between tumor and normal tissue and we evaluated the correlation with IDH1 mutation.

RESULTS

We observed a positive correlation with IDH1 status and RD and MD data. No correlation was demonstrated between IDH1 status and FA and AD.

DISCUSSION

Our results support the hypothesis that the number of residual axonal fibers, extracellular matrix composition and the presence of colliquated tissue, may together contribute to a global RD increase in HGG, with a relatively higher increase in IDH1m tumors.

CONCLUSIONS

Our data are in favor of a need for multimodal advance evaluation of HGG. DTI metrics help to analyze IDH1 mutation status, in order to better characterize the lesions and to tailor treatment and follow up.

GEN-O-MA project: an Italian network studying clinical course and pathogenic pathways of moyamoya disease-study protocol and preliminary results

BACKGROUND

GENetics of mOyaMoyA (GEN-O-MA) project is a multicenter observational study implemented in Italy aimed at creating a network of centers involved in moyamoya angiopathy (MA) care and research and at collecting a large series and bio-repository of MA patients, finally aimed at describing the disease phenotype and clinical course as well as at identifying biological or cellular markers for disease progression. The present paper resumes the most important study methodological issues and preliminary results.

METHODS

Nineteen centers are participating to the study. Patients with both bilateral and unilateral radiologically defined MA are included in the study. For each patient, detailed demographic and clinical as well as neuroimaging data are being collected. When available, biological samples (blood, DNA, CSF, middle cerebral artery samples) are being also collected for biological and cellular studies.

RESULTS

Ninety-eight patients (age of onset mean ± SD 35.5 ± 19.6 years; 68.4% females) have been collected so far. 65.3% of patients presented ischemic (50%) and haemorrhagic (15.3%) stroke. A higher female predominance concomitantly with a similar age of onset and clinical features to what was reported in previous studies on Western patients has been confirmed.

CONCLUSION

An accurate and detailed clinical and neuroimaging classification represents the best strategy to provide the characterization of the disease phenotype and clinical course. The collection of a large number of biological samples will permit the identification of biological markers and genetic factors associated with the disease susceptibility in Italy.

Hippocampal Subfield Volumes in Patients With First-Episode Psychosis

Background

Hippocampal abnormalities have been largely reported in patients with schizophrenia and bipolar disorder, and are considered to be involved in the pathophysiology of the psychosis. The hippocampus consists of several subfields but it remains unclear their involvement in the early stages of psychosis.

Aim

The aim of this study was to investigate volumetric alterations in hippocampal subfields in patients at the first-episode psychosis (FEP).

Methods

Magnetic resonance imaging (MRI) data were collected in 134 subjects (58 FEP patients; 76 healthy controls [HC]). A novel automated hippocampal segmentation algorithm was used to segment the hippocampal subfields, based on an atlas constructed from ultra-high resolution imaging on ex vivo hippocampal tissue. The general linear model was used to investigate volume differences between FEP patients and HC, with age, gender and total intracranial volume as covariates.

Results

We found significantly lower volumes of bilateral CA1, CA4, and granule cell layer (GCL), and of left CA3, and left molecular layer (ML) in FEP patients compared to HC. Only the volumes of the left hippocampus and its subfields were significantly lower in FEP than HC at the False Discovery Rate (FDR) of 0.1. No correlation was found between hippocampal subfield volume and duration of illness, age of onset, duration of medication, and Positive and Negative Syndrome Scale (PANSS).

Conclusion

We report abnormally low volumes of left hippocampal subfields in patients with FEP, sustaining its role as a putative neural marker of psychosis onset.

Indocyanine Green Videoangiographic-Guided Cannulation of the Superior Ophthalmic Vein for Endovascular Treatment of Carotid-Cavernous Fistulas

Direct exposure and cannulation of the superior ophthalmic vein (SOV) provides an alternative access to reach the cavernous sinus for carotid-cavernous fistula (CCF) embolization, when classic transvenous routes through the inferior petrosal sinus (IPS) or facial vein are not feasible. We have used indocyanine green (ICG)-videoangiography to study intraoperatively the flow inside the SOV in two cases of indirect CCF. In this paper, we report the operative technique and the result of ICG videoangiographic-guided cannulation of the SOV for endovascular treatment of CCF. Two male patients, of 59 and 66 years of age respectively, presented at our Institution with right decreased visual acuity, persistent binocular diplopia and painful ophthalmoplegia, chemosis and proptosis, due to right unilateral indirect CCF fistula. The endovascular transvenous approach failed in one case due to thrombosis of the inferior petrosal sinus (IPS) and the extreme tortuosity of the angular vein. In the other case, it was considered unfeasible due to an unfavourable vascular angioarchitecture. For this reason, an ICG videoangiographic-guided cannulation of the SOV, followed by endovascular obliteration of the CCF, was performed. CCF was cured in both cases with this approach. No additional neurological deficits and no complications due to SOV cannulation were registered during the hospital stay. There were no fistula recurrences during the mean follow-up of 18 months. ICG-videoangiography is a simple, fast and cost-effective technique that can be reliably applied in SOV cannulation for subsequent indirect CCF embolization.

Sacral dural arteriovenous fistulas: a diagnostic and therapeutic challenge – single-centre experience of 13 cases and review of the literature

Background

Sacral dural arteriovenous fistulas (DAVFs) are rare vascular abnormalities of the spine characterised by slowly progressive symptoms that can mimic different myelopathy disorders.

Object

To report our single Institution experience with sacral DAVFs.

Methods

We retrospectively reviewed the clinical records of patients admitted from 1 January 2006 to 31 December 2016 with a diagnosis of sacral DAVFs, treated by endovascular embolisation or surgical clipping. Clinical presentation, imaging characteristics, treatment results and follow-up were analysed.

Results

We identify 13 patients with sacral DAVFs supplied by lateral sacral arteries. Clinical presentation was characterised by different degrees of motor weakness and sphincter disturbances. In all patients, spinal MRI showed spinal cord hyperintensities with enhancement and prominent perimedullary vessels. Selective internal iliac angiography was mandatory to identify the exact location of the fistula. A complete embolisation was achieved in eight patients performing a single endovascular embolisation and in three patients performing a single surgical disconnection: two patients required combined procedures. Follow-up imaging showed a complete resolution of the spinal cord hyperintensities in 81% of patients and a reduction of the intramedullary enhancement in 91%. Gait improvement was observed in 73% of patients, while remaining stable in 27%. Sphincter disturbances improved in 36% of patients and remained stable in 64%.

Conclusion

Awareness of sacral location of DAVFs is critical because standard spinal angiography will not identify sacral supplies, unless internal iliac arteries are properly examined. In our experience, the endovascular treatment show results comparable to surgery when the fistula point is correctly disconnected.

Arteriovenous fistulae of the filum terminale

Filum terminale arteriovenous fistulae are a rare type of arteriovenous shunt generally characterized by a single direct communication between the artery of the filum terminale and a single draining vein. These intradural arteriovenous shunts are three times more common in men than women (mean age 55 years). Symptoms are related to venous congestion, vascular hypertension, and a putative chronic steal phenomenon which result in spinal cord ischemia and myelopathy. Interestingly, hemorrhage has never been reported as a mode of presentation. MRI demonstrates increased flow voids and T2 changes involving the conus and the lower spinal cord, and these findings are not dissimilar from those seen with the more common type 1 spinal dural arteriovenous fistulae. Thus conventional spinal angiography is necessary for a definitive diagnosis and to localize exactly the site of the fistula. Both surgical interruption of the fistula and endovascular embolization are safe and effective therapeutic modalities. However, because of the very small caliber of the feeding artery, endovascular therapy is often not feasible; and thus, surgery remains the method more commonly utilized for their treatment. Definitive treatment consists of obliteration of the direct arteriovenous shunt. In this review, we describe the anatomy, pathophysiology, clinical presentation, imaging, and treatment options of these less common intradural arteriovenous shunts.

Erratum to: Activations in gray and white matter are modulated by uni-manual responses during within and inter-hemispheric transfer: effects of response hand and right-handedness

The original version of this article unfortunately contained a mistake. The family name of Paolo Brambilla was incorrectly spelled as Bambilla.

Medial Tentorial Dural Arteriovenous Fistula Embolization: Single Experience with Embolic Liquid Polymer SQUID and Review of the Literature

BACKGROUND

Tentorial dural arteriovenous fistulas (DAVFs) are uncommon, complex fistulas located between the leaves of the tentorium cerebelli with a specific anatomic and clinical presentation characterized by high hemorrhagic risk. We present a rare case of a medial tentorial DAVF successfully managed via transarterial embolization using SQUID liquid polymer.

CASE DESCRIPTION

A 60-year-old woman presented with a history of left progressive hearing loss and tinnitus for >1 year. Cerebral angiography demonstrated the presence of a medial tentorial DAVF with multiple arterial feeders, including the artery of Davidoff and Schechter; reverse venous outflow was observed in the inferior sagittal sinus and in multiple cortical veins. The patient underwent transarterial embolization with SQUID liquid polymer, an embolic agent that provides 2 different viscous formulations to cast the DAVF. The procedure went well without any complication, and the patient regained her preoperative status. In the postprocedural period, the patient experienced complete resolution of tinnitus. At 6 months, she remained asymptomatic, and cerebral angiography confirmed complete, stable occlusion of the fistula and normalization of cerebral deep venous outflow.

CONCLUSIONS

Medial tentorial DAVFs are considered the most complex DAVFs because of their location and extensive vascular supply. Our literature review focused on endovascular treatment of tentorial DAVFs to highlight the usefulness of new embolic agents in management of these diseases. To our knowledge, we report the first successful use of SQUID liquid polymer in management of a tentorial DAVF.

Vasculogenic and Angiogenic Pathways in Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) is a slowly progressing steno-occlusive cerebrovascular disease. The typical moyamoya vessels, which originate from an initial stenosis of the internal carotid, highlight that increased and/or abnormal angiogenic, vasculogenic and arteriogenic processes are involved in the disease pathophysiology.

OBJECTIVE

Herein, we summarize the current knowledge on the most important signaling pathways involved in MMD vessel formation, particularly focusing on the expression of growth factors and function of endothelial progenitor cells (EPCs).

METHODS AND RESULTS

Higher plasma concentrations of vascular endothelial growth factor, matrix metalloproteinase, hepatocyte growth factor, and interleukin-1β were reported in MMD. A specific higher level of basic fibroblast growth factor was also found in the cerebrospinal fluid of these patients. Finally, the number and the functionality of EPCs were found to be increased. In spite of the available data, the approaches and findings reported so far do not give an evident correlation between the expression levels of the aforementioned growth factors and MMD severity. Furthermore, the controversial results provided by studies on EPCs, do not permit to understand the true involvement of these cells in MMD pathophysiology.

CONCLUSION

Further studies should thus be implemented to extend our knowledge on processes regulating both the arterial stenosis and the excessive formation of collateral vessels. Moreover, we suggest advances of integrated approaches and functional assays to correlate biological and clinical data, arguing for the development of new therapeutic applications for MMD.

Alterazioni meningee da ipotensione liquorale essenziale

Gli autori descrivono un caso di ipotensione liquorale essenziale con sindrome clinica ad esordio acuto, costituita da cefalea gravativa che si riduceva parzialmente in decubito orizzontale, regredita in cinque mesi. Vari esami RM dimostrarono la presenza di un ispessimento durale con accentuazione dopo contrasto, sia in sede endocranica che a livello cervicale, ed anche un sottile e circoscritto scollamento durale con lievi fenomeni emorragici; alla remissione clinica si accompagnò la normalizzazione del quadro neuroradiologico. Vengono discussi i possibili meccanismi patogenetici delle alterazioni durali alla luce dell'anatomia degli strati profondi della dura e ne vengono sottolineati gli aspetti radiologici.

La risonanza magnetica nelle encefalomiopatie mitocondriali

Le encefalopatie mitocondriali sono un gruppo eterogeneo di malattie, in parte ancora in corso di definizione, per cui è sempre necessaria una conferma biochimica.

Alcune malattie mitocondriali, come i difetti della β- ossidazione degli acidi grassi, possono causare gravi squilibri metabolici con ipoglicemia e coma che si ripercuotono in modo aspecifico sul sistema nervoso centrale determinando quadri di sofferenza cerebrale diffusa. Altre malattie mitocondriali determinano danni più specifici sul SNC. Nella prima infanzia la malattia più caratteristica è la malattia di Leigh, che determina alterazioni principalmente nel tegmento pontino e mesencefalico e nei nuclei della base. Alcuni casi presentano lesioni caratteristiche nei nuclei subtalamici, altri presentano reperti più aspecifici e diffusi simili a quadri di leucodistrofia.

In età più tardiva (seconda infanzia o età adulta) la malattia più interessante dal punto di vista neuroradiologico è il MELAS, che presenta lesioni cortico-sottocorticali nelle regioni posteriori con distribuzione non tipicamente vascolare, sopra e sottotentoriali, che tuttavia possono essere ricondotte ai territori più distali dei vasi. Calcificazioni nei nuclei della base sono presenti in circa la metà dei casi.

Un'altra encefalopatia mitocondriale dell'età giovanile o adulta è la sindrome di Kearns-Sayre, in cui la RM può dimostrare alterazioni nel tronco, nei talami, nei nuclei della base e nella sostanza bianca sottocorticale.

Alterazioni nel neostriato possono essere osservate nelle sindromi distoniche associate ad atrofia ottica di Leber. Non sono descritte invece lesioni specifiche nel MERRF, in cui atrofia ed alterazioni della sostanza bianca sono state occasionalmente osservate. Esistono infine casi che presentano quadri clinici e neuroradiologici intermedi tra le varie sindromi mitocondriali.

L'obiettivo di questa revisione è dimostrare alcuni aspetti tipici delle sindromi più comuni e indicare quali aspetti neuroradiologici, a volte inattesi, devono suggerire l'ipotesi di encefalopatia mitocondriale, permettendo cosi di indirizzare in modo corretto ulteriori indagini diagnostiche.

Aneurysm Study of Pipeline in an Observational Registry (ASPIRe)

BACKGROUND AND OBJECTIVE

Few prospective studies exist evaluating the safety and efficacy of the Pipeline Embolization Device (PED) in the treatment of intracranial aneurysms. The Aneurysm Study of Pipeline In an observational Registry (ASPIRe) study prospectively analyzed rates of complete aneurysm occlusion and neurologic adverse events following PED treatment of intracranial aneurysms.

MATERIALS AND METHODS

We performed a multicenter study prospectively evaluating patients with unruptured intracranial aneurysms treated with PED. Primary outcomes included (1) spontaneous rupture of the Pipeline-treated aneurysm; (2) spontaneous nonaneurysmal intracranial hemorrhage (ICH); (3) acute ischemic stroke; (4) parent artery stenosis, and (5) permanent cranial neuropathy. Secondary endpoints were (1) treatment success and (2) morbidity and mortality at the 6-month follow-up. Vascular imaging was evaluated at an independent core laboratory.

RESULTS

One hundred and ninety-one patients with 207 treated aneurysms were included in this registry. The mean aneurysm size was 14.5 ± 6.9 mm, and the median imaging follow-up was 7.8 months. Twenty-four aneurysms (11.6%) were small, 162 (78.3%) were large and 21 (10.1%) were giant. The median clinical follow-up time was 6.2 months. The neurological morbidity rate was 6.8% (13/191), and the neurological mortality rate was 1.6% (3/191). The combined neurological morbidity/mortality rate was 6.8% (13/191). The most common adverse events were ischemic stroke (4.7%, 9/191) and spontaneous ICH (3.7%, 7/191). The complete occlusion rate at the last follow-up was 74.8% (77/103).

CONCLUSIONS

Our prospective postmarket study confirms that PED treatment of aneurysms in a heterogeneous patient population is safe with low rates of neurological morbidity and mortality. Patients with angiographic follow-up had complete occlusion rates of 75% at 8 months.

Republished: Advanced digital subtraction angiography and MR fusion imaging protocol applied to accurate placement of flow diverter device

In recent years there has been a progressive increase in interventional neuroradiology procedures, partially due to improvements in devices, but also to the simultaneous development of technologies and radiological images. Cone beam CT (Dyna-CT; Siemens) is a method recently used to obtain pseudo CT images from digital subtraction angiography (DSA) with a flat panel detector. Using dedicated software, it is then possible to merge Dyna-CT images with images from a different source. We report here the usefulness of advanced DSA techniques (Syngo-Dyna CT, three-dimensional DSA iPilot) for the treatment of an intracranial aneurysm with a flow diverter device. Merging MR and Dyna-CT images at the end of the procedure proved to be a simple and rapid additional method of verifying the success of the intervention.

Advanced digital subtraction angiography and MR fusion imaging protocol applied to accurate placement of flow diverter device

In recent years there has been a progressive increase in interventional neuroradiology procedures, partially due to improvements in devices, but also to the simultaneous development of technologies and radiological images. Cone beam CT (Dyna-CT; Siemens) is a method recently used to obtain pseudo CT images from digital subtraction angiography (DSA) with a flat panel detector. Using dedicated software, it is then possible to merge Dyna-CT images with images from a different source. We report here the usefulness of advanced DSA techniques (Syngo-Dyna CT, three-dimensional DSA iPilot) for the treatment of an intracranial aneurysm with a flow diverter device. Merging MR and Dyna-CT images at the end of the procedure proved to be a simple and rapid additional method of verifying the success of the intervention.

Cerebrovascular reactivity by quantitative magnetic resonance angiography with a Co₂ challenge. Validation as a new imaging biomarker

Assessment of cerebrovascular reactivity (CVR) is essential in cerebrovascular diseases, as exhausted CVR may enhance the risk of cerebral ischemic events. Transcranial Doppler (TCD) with a vasodilatory stimulus is currently used for CVR evaluation. Scanty data are available for Quantitative Magnetic Resonance Angiography (QMRA), which supplies higher spatial resolution and quantitative cerebral blood flow values. Aims of our pilot study were: (a) to assess safety and feasibility of CO2 administration during QMRA, (b) evaluation of CVR under QMRA compared to TCD, and (c) quantitative evaluation of blood flow from the major intracranial arterial vessels both at rest and after CO2. CVR during 5% CO2 air breathing was measured with TCD as a reference method and compared with QMRA. Fifteen healthy subjects (age 60.47 ± 2.24; male 11/15) were evaluated at rest and during CO2 challenge. Feasibility and safety of QMRA under CO2 were ensured in all subjects. CVR from middle cerebral artery territory was not statistically different between TCD and MRI (p>0.05). Mean arterial pressure (MAP) and heart rate (HR) increased during QMRA and TCD (MAP p=0.007 and p=0.001; HR p=0.043 and p=0.068, respectively). Blood flow values from all intracranial vessels increased after CO2 inhalation (p<0.001). CO2 administration during QMRA sessions is safe and feasible. Good correlation in terms of CVR was obtained comparing TCD and QMRA. Blood flow values significantly increased from all intracranial arterial vessels after CO2. Studies regarding CVR in physiopathological conditions might consider the utilization of QMRA both in routine clinical settings and in research projects.

Microembolization during carotid artery stenting in patients with high-risk, lipid-rich plaque. A randomized trial of proximal versus distal cerebral protection

OBJECTIVES

The goal of this study was to compare the rate of cerebral microembolization during carotid artery stenting (CAS) with proximal versus distal cerebral protection in patients with high-risk, lipid-rich plaque.

BACKGROUND

Cerebral protection with filters partially reduces the cerebral embolization rate during CAS. Proximal protection has been introduced to further decrease embolization risk.

METHODS

Fifty-three consecutive patients with carotid artery stenosis and lipid-rich plaque were randomized to undergo CAS with proximal protection (MO.MA system, n = 26) or distal protection with a filter (FilterWire EZ, n = 27). Microembolic signals (MES) were assessed by using transcranial Doppler during: 1) lesion wiring; 2) pre-dilation; 3) stent crossing; 4) stent deployment; 5) stent dilation; and 6) device retrieval/deflation. Diffusion-weighted magnetic resonance imaging was conducted before CAS, after 48 h, and after 30 days.

RESULTS

Patients in the MO.MA group had higher percentage diameter stenosis (89 ± 6% vs. 86 ± 5%, p = 0.027) and rate of ulcerated plaque (35% vs. 7.4%; p = 0.019). Compared with use of the FilterWire EZ, MO.MA significantly reduced mean MES counts (p < 0.0001) during lesion crossing (mean 18 [interquartile range (IQR): 11 to 30] vs. 2 [IQR: 0 to 4]), stent crossing (23 [IQR: 11 to 34] vs. 0 [IQR: 0 to 1]), stent deployment (30 [IQR: 9 to 35] vs. 0 [IQR: 0 to 1]), stent dilation (16 [IQR: 8 to 30] vs. 0 [IQR: 0 to 1]), and total MES (93 [IQR: 59 to 136] vs. 16 [IQR: 7 to 36]). The number of patients with MES was higher with the FilterWire EZ versus MO.MA in phases 3 to 5 (100% vs. 27%; p < 0.0001). By multivariate analysis, the type of brain protection was the only independent predictor of total MES number. No significant difference was found in the number of patients with new post-CAS embolic lesion in the MO.MA group (2 of 14, 14%) as compared with the FilterWire EZ group (9 of 21, 42.8%).

CONCLUSIONS

In patients with high-risk, lipid-rich plaque undergoing CAS, MO.MA led to significantly lower microembolization as assessed by using MES counts.

Percutaneous vertebroplasty in a series of myasthenic patients with steroid-induced symptomatic vertebral fractures

Vertebral compression fractures (VFs) are observed in 30-50 % of patients affected by steroid-induced osteoporosis, with consequentially severe back pain and functional limitation. An alternative treatment to medical therapy for pain caused by recent VFs is percutaneous vertebroplasty (PVP). Patients were treated by PVP after careful selection, based on the presence of persistent pain not resolved by standard medical therapy, correlation between pain and level of the VF, and neuroradiological features. We performed PVP in 4 patients with generalized MG associated with recent steroid-induced symptomatic VFs. Relief from pain was very rapid, usually within 24 h, and retained at a 3-month evaluation. No severe complication or MG worsening were observed in the post-operative period. Although clinical indication for PVP is still controversial, in our experience PVP is a useful and safe tool to be considered in the management of recent steroid-induced symptomatic VFs in selected MG patients.

White matter involvement in idiopathic Parkinson disease: a diffusion tensor imaging study

BACKGROUND AND PURPOSE

Diffusion tensor imaging (DTI) offers a unique window on the connectivity changes, extending beyond the basal ganglia, which accompany the cognitive symptoms of Parkinson disease (PD). The primary purpose of this study was to assess the microstructural damage to cerebral white matter occurring in idiopathic PD.

MATERIALS AND METHODS

Our sample included patients with PD without dementia (n = 10; Hoehn and Yahr stages I and II; Unified Parkinson Disease Rating Scale, 20.5 +/- 8.3; and Mini-Mental State Examination, 28.3 +/- 1.5) and age-matched healthy control subjects (n = 10). DTI was performed on a 1.5T scanner, and mean diffusivity (MD) and fractional anisotropy (FA) maps were obtained. Regions of interest (ROIs) were drawn on the major fiber bundles as well as on gray matter nuclei.

RESULTS

In patients, the MD was increased at borderline significance in the substantia nigra but was unaltered in the thalamus, globus pallidus, putamen, and in the head of the caudate nucleus. The FA and MD were unaltered in the corticospinal tract in the midbrain and at the level of the internal capsule, and in the splenium of the corpus callosum. By contrast, the MD was increased and the FA was decreased in the genu of the corpus callosum and in the superior longitudinal fasciculus; in the cingulum, only the MD was altered. The observed changes were not significantly lateralized.

CONCLUSIONS

Widespread microstructural damage to frontal and parietal white matter occurs already in the early stages of PD.

Self-closing surgical clips for use in pericallosal artery–pericallosal artery side-to-side bypass

The authors demonstrate the feasibility of a new procedure to create intracranial interrupted microvascular anastomosis. Self-closing nitinol surgical clips were used for a pericallosal artery–pericallosal artery side-to-side bypass in a 52-year-old man harboring an unruptured large aneurysm located on the right A2 segment. The outflow artery was found to arise from the dome of the aneurysm, which was considered unsuitable for stand-alone clip ligation or coil occlusion. After bypass patency was intraoperatively confirmed using near-infrared indocyanine green videoangiography, the aneurysm and feeding artery were embolized with coils and safely occluded. Both postoperative courses were uneventful. The patient was discharged neurologically intact on the 5th postembolization day. Postprocedure angiography demonstrated no ipsilateral aneurysm filling and excellent bilateral distal outflow from the left anterior cerebral artery.

Optimization and validation of an automated voltammetric stripping technique for ultratrace metal analysis

A new automated batch method for the determination of ultratrace metals (nanogram per liter level) was developed and validated. Instrumental and chemical parameters affecting the performance of the method were carefully assessed and optimized. A wide range of voltammetric methods under different chemical conditions were tested. Cadmium, lead and copper were determined by anodic stripping voltammetry (ASV), while nickel, cobalt, rhodium and uranium by adsorptive cathodic stripping voltammetry (AdCSV). The figures of merit of all of these methods were determined: very good precision and accuracy were achieved, e.g. relative percentage standard deviation in the 4-13% for ASV and 2-5% for AdCSV. The stripping methods were applied to the determination of cadmium, lead, copper, nickel, cobalt, rhodium and uranium in lake water samples and the results were found to be comparable with ICP-MS data.

Obliteration of a giant fusiform carotid terminus-M1 aneurysm after distal clip application and extracranial-intracranial bypass. Case report

Giant intracranial aneurysms may not be amenable to direct surgical clipping or endovascular coiling because of three critical factors: 1) lack of clear aneurysmal neck; 2) giant size; 3) involvement with critical perforating or branch vessels. Techniques of flow redirection, however, may offer an alternative treatment strategy for these difficult lesions. In this paper, we report on the use of this alternative strategy in the successful treatment of a left giant fusiform carotid terminus-M1 aneurysm in a 16 year-old boy suffering from Ehler-Danlos disease. This patient was admitted to our Institution because his aneurysm was continuing to be increasing in size, despite a previous ligation of his left cervical ICA which was performed at another institution 2 years earlier after the patient had experienced a hemorrhagic stroke. Upon admission, a neurological examination revealed a slight motor aphasia with mild right hemiparesis, remnant of the ancient stroke. Because of its size and the involvement with M1 perforating arteries, a direct aneurysm attack was deemed inadvisable. After an initial ECA-ICA high flow bypass which spontaneously thrombosed, we performed a repeated high flow bypass with the application of a single clip on M1, right distal to the fusiform dilatation. After an uneventful postoperative course, we were unable to observe any new neurological deficits after surgery. A CT scan on postoperative day 1 revealed that the aneurysm had undergone a spontaneous thrombosis which was completely obliterated at the time of a 6-month follow-up angiogram. At that time, the ECA-ICA bypass was found to be patent. In conclusion the alternative of flow alteration strategies can be successfully used in the treatment of aneurysms that cannot be safely trapped or occluded by traditional neurosurgical methods.

SELF-CLOSING U-CLIPS FOR INTRACRANIAL MICROANASTOMOSES IN HIGH-FLOW ARTERIAL BYPASS

OBJECTIVE

Self-closing nitinol U-clips (Medtronic, Inc., Minneapolis, MN) have been used to create vascular microanastomoses by vascular surgeons. This device eliminates the need for suture management and knot tying. Therefore, a high-quality interrupted microvascular anastomosis can be obtained in a shorter period of time. This is the first report of a U-clip intracranial arterial microanastomosis for a high-flow extracranial-intracranial bypass using a radial artery graft.

CLINICAL PRESENTATION

A 24-year-old woman with a history of chronic headache was admitted to the National Neurological Institute Carlo Besta after a brain computed tomographic scan revealed a giant serpentine aneurysm of her right middle cerebral artery. Magnetic resonance angiography and four-vessel angiography confirmed the diagnosis and ruled out other lesions.

INTERVENTION

A radial artery graft was used to create a high-flow bypass between the external carotid artery and the postaneurysmal M2 segment of the right middle cerebral artery. Nitinol self-closing U-clips were used for the interrupted intracranial microanastomosis. After intraoperative near-infrared indocyanine green video angiography confirmed the bypass patency, the aneurysm could be trapped.

CONCLUSION

The postoperative course was uneventful. The patient was discharged on the seventh postoperative day and was neurologically intact. Postoperative angiography documented the successful exclusion of the aneurysm and the presence of revascularization of the distal branches of the right middle cerebral artery through the bypass. This case demonstrates the efficacy of U-clips for intracranial microanastomoses.

Meningiomas invading the superior sagittal sinus: surgical experience in 108 cases

OBJECTIVE

Radical resection of meningiomas invading the superior sagittal sinus (SSS) presents several hazards. Some surgeons consider SSS invasion a contraindication for complete resection, and others advocate total resection with venous reconstruction. There is a lack of published large series to provide definitive guidelines for the surgical treatment of these complex cases. We report our 15-year experience with surgery of parasagittal meningiomas invading the SSS.

METHODS

Between 1986 and 2001, 108 patients (73 women, 35 men; age range, 22-83 yr; mean age, 56.2 yr) underwent surgery at the Neurological Institute "C. Besta" of Milan for tumors invading the SSS. Parasagittal meningiomas not invading the SSS were excluded from this series.

RESULTS

Simpson Grade I to II removal was achieved in 100 patients. Thirty patients with meningiomas totally occluding the SSS had complete resection of the encased portion of the sinus. Histological examination revealed 86 benign (79.6%), 16 atypical (14.8%), and 4 malignant (3.7%) meningiomas along with 2 hemangiopericytomas. There were two perioperative deaths. Serious complications included brain swelling (nine patients; 8.3%) and postoperative hematoma (two patients; 1.85%). Follow-up ranged from 19 to 223 months (mean, 79.5 mo). One patient was lost to follow-up. Tumors recurred in 15 patients (13.9%). After multivariate analysis, histological type, tumor size, and Simpson grade were confirmed as significant independent prognostic factors for recurrence.

CONCLUSION

On the basis of our results, we conclude that if the sinus is partially invaded, it can be opened to obtain as complete a resection as possible and to attempt to preserve the patency of the sinus. If the sinus is obstructed, the portion of the sinus involved can be resected completely. In both situations, extreme care is vital to preservation of cortical veins, which may offer important collateral drainage. With our approach, good results are achieved and it is not necessary to reconstruct the sinus.

Spontaneous low cerebrospinal pressure: a mini review

Spontaneous intracranial hypotension (SIH) is a syndrome of low cerebrospinal fluid (CSF) pressure characterised by postural headaches in patients without any history of dural puncture or penetrating trauma. Described by Schaltenbrand in 1938, SIH is thought to result from an occult CSF leak resulting in decreased CSF volume and, consequently, in low CSF pressure. Magnetic resonance imaging of the head and spine has improved the diagnosis of the syndrome showing peculiar radiographic abnormalities including diffuse pachymeningeal enhancement, subdural fluid collections and downward displacement of the cerebral structures. Treatment of SIH headache should start with conservative, non-invasive therapies while epidural blood patch has emerged as the treatment of choice for those symptomatic patients who have failed medical noninvasive approaches.

Headache and intracranial hypotension: neuroradiological findings

The cardinal and classic features of postural headache and low cerebrospinal fluid (CSF) pressure in intracranial hypotension may not dominate the clinical picture of the syndrome and may be associated with additional various neurological symptoms and signs. Reports of unusual clinical presentations continue to appear in the literature. Despite the considerable variability of the clinical spectrum, neuroradiological studies reveal more constant and characteristic features. Brain MRI findings include intracranial pachymeningeal thickening and post-contrast enhancement, subdural fluid collections and downward displacement or "sagging" of the brain. Spinal MRI findings include collapse of the dural sac with a festooned appearance, intense epidural enhancement owing to dilatation of the epidural venous plexus, and possible epidural fluid collections. In fact, spinal studies may demonstrate CSF leakage from spinal dural defects, which are considered the most common cause of the syndrome. Myelo-MR may suggest the possible point of CSF leakage, by demonstrating an irregular root sleeve; myelo-CT and radioisotope myelocisternography (RMC) are often needed to confirm the point of CSF leakage. Neuroimaging studies are, therefore, essential for suggesting and confirming the diagnosis.

Hyperhomocysteinemia and other thrombophilic risk factors in 26 patients with cerebral venous thrombosis

Despite the continuous description of new conditions pre-disposing for cerebral venous thrombosis (CVT), no apparent cause is found in about 30% of cases. Hyperhomocysteinemia (hyper-Hcy) is an established risk factor for deep venous thrombosis and stroke but has not been clearly associated with increased risk of CVT. We assessed the prevalence of hyper-Hcy and other thrombophilic risk factors in a population of 26 consecutive patients with non-pyogenic CVT, by review of a prospectively maintained database. The prevalences of hyper-Hcy and prothrombin G20210A, factor V G1691A and methylenetetrahydrofolate reductase (MTHFR) C677T mutations in these patients were compared with those in 100 healthy controls and 100 patients with cerebroarterial disease. The prevalence of hyper-Hcy was greater in patients with CVT (10/26, 38.5%) than healthy controls (13/100; OR 4.18, 95% CI 1.58-11.16) and comparable with that in patients with cerebroarterial disease (42/100). No significant differences were found in the prevalences of prothrombin or MTHFR mutation. No factor V mutation was found. Our findings indicate that hyper-Hcy is associated with an increased risk of CVT. Additional prospective cohort studies on large series of patients are required to clarify the time relationship between hyper-Hcy and the thrombotic event.

Development and rupture of a de novo basilar artery aneurysm after surgical removal of a cerebellar arteriovenous malformation

BACKGROUND

The de novo development of an aneurysm in an previously normal artery is an uncommon event. We describe a patient who developed a de novo bleeding aneurysm of the basilar artery in the three weeks following the surgical removal of a large cerebellar AVM. METHOD-FINDINGS: A 48-year-old man suddenly developed transient headache, vertigo and disturbance of balance. Neuroradiological examinations showed the presence of a large AVM of the right cerebellar hemisphere. The AVM was removed successfully; following the operation there were repeated bleeding episodes at the operating site, requiring surgical evacuation. Three weeks after the AVM removal he suffered from a massive subarachnoid haemorrhage due to the rupture of an aneurysm developed de novo in the basilar artery.

INTERPRETATION

This is the first reported case, to our knowledge, of a de novo aneurysm developed in an artery hemodynamically related to a surgically removed AVM. This complication was probably due to the postoperative hemodynamic changes in the vessels afferent to the AVM, associated with arterial wall dysplasia.

Shunt migration into the sphenoid sinus: case report

OBJECTIVE AND IMPORTANCE

Shunt catheter migration is a potential complication of cerebrospinal fluid shunting procedures. We report an unusual case of proximal shunt migration into the sphenoid sinus. To our knowledge, there have been no previous reports of shunt migration through the bony structures of the cranial base.

CLINICAL PRESENTATION

A 41-year-old man who had had a cyst-to-peritoneum shunt placed 21 years earlier for a temporal lobe arachnoid cyst presented with cerebrospinal fluid rhinorrhea. Neuroradiological imaging revealed migration of the shunt catheter through the medial wall of the middle temporal fossa into the sphenoid sinus.

INTERVENTION

The patient underwent shunt removal and repair of the dural defect. Intraoperatively, the proximal catheter tip was found in the sphenoid sinus with dural and bony erosion. The patient made an uneventful recovery.

CONCLUSION

We present a unique long-term complication associated with intracranial shunt catheters. We hypothesize that excessive proximal catheter length and chronic cerebrospinal fluid pulsations contributed to migration of the catheter into the sphenoid sinus.