Functional and radiological outcomes after bridging therapy versus direct thrombectomy in stroke patients with unknown onset: Bridging therapy versus direct thrombectomy in unknown onset stroke patients with 10-point ASPECTS.

BACKGROUND AND PURPOSE: The aim was to assess functional and radiological outcomes after bridging therapy (intravenous thrombolysis plus mechanical thrombectomy) versus direct mechanical thrombectomy (MT) in unknown onset stroke patients. METHODS: A cohort study was conducted on prospectively collected data from unknown onset stroke patients who received endovascular procedures at ≤6 h from symptom recognition or awakening time. RESULTS: Of the 349 patients with a 10-point Alberta Stroke Program Early Computed Tomography Score (ASPECTS), 248 received bridging and 101 received direct MT. Of the 134 patients with 6-9-point ASPECTS, 123 received bridging and 111 received direct MT. Each patient treated with bridging was propensity score matched with a patient treated with direct MT for age, sex, study period, pre-stroke disability, stroke severity, type of stroke onset, symptom recognition to groin time (or awakening to groin time), ASPECTS and procedure time. In the two matched groups with 10-point ASPECTS (n = 73 vs. n = 73), bridging was associated with higher rates of excellent outcome (46.6% vs. 28.8%; odds ratio 2.302, 95% confidence interval 1.010-5.244) and successful recanalization (83.6% vs. 63%; odds ratio 3.028, 95% confidence interval 1.369-6.693) compared with direct MT; no significant association was found between bridging and direct MT with regard to rate of symptomatic intracerebral hemorrhage (0% vs. 1.4%). In the two matched groups with 6-9-point ASPECTS (n = 45 vs. n = 45), no significant associations were found between bridging and direct MT with regard to rates of excellent functional outcome (44.4% vs. 31.1%), successful recanalization (73.3% vs. 76.5%) and symptomatic intracerebral hemorrhage (0% vs. 0%). CONCLUSIONS: Bridging at ≤ 6 h of symptom recognition or awakening time was associated with better functional and radiological outcomes in unknown onset stroke patients with 10-point ASPECTS.

Automated double-cone-beam CT fusion technique. Enhanced evaluation of glue distribution in cases of spinal dural arteriovenous fistula (SDAVF) embolisation.

OBJECTIVES: Spinal dural arteriovenous fistulas (SDAVFs) are acquired diseases that represent the majority of all arteriovenous spinal shunts, leading to progressive and disabling myelopathy. Treatment is focused on accurately disconnecting the fistula point. We present our experience with the double-cone-beam CT fusion technique successfully applied to evaluate treatment results in a series of SDAVFs. METHODS: Between November 2011 and December 2015 we performed double-DynaCT acquisition (pre- and post-embolisation) in 12 cases of SDAVF. RESULTS: A successful DynaCT fusion technique was only achieved in the group of patients with pre- and post-treatment images acquired at the same time as the treatment session, under general anaesthesia (4/12). DynaCT performed on different days proved to be inadequate for the automated fusion technique because of changes in the body position (8/12). CONCLUSIONS: A pre-treatment flat-panel cone-beam CT with contrast, at the time of diagnostic angiography, can be very helpful to detect the correct level of the fistula and the relationship between the fistula and the surrounding structures. In case of the endovascular approach, additional post-treatment native acquisition merged with the pre-treatment acquisition (double-cone-beam CT fusion technique) permits to immediately evaluate the distribution of the glue cast and to confirm the success of the procedure. KEY POINTS: • SDAVF treatment must be aimed to occlude the fistula point shunt. • Native post-operative cone-beam CT permits high-spatial-resolution imaging of the embolic cast. • The automated double-cone-beam CT fusion technique (pre/post) accurately demonstrates intravascular glue distribution after embolisation. • Patient movements should be avoided to obtain good technical results.

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.

Validation of an isotope dilution, ICP-MS method based on internal mass bias correction for the determination of trace concentrations of Hg in sediment cores.

The development and validation of a method for the determination of mercury in sediments using a sector field inductively coupled plasma mass spectrometer (SF-ICP-MS) for detection is described. The utilization of isotope dilution (ID) calibration is shown to solve analytical problems related to matrix composition. Mass bias is corrected using an internal mass bias correction technique, validated against the traditional standard bracketing method. The overall analytical protocol is validated against NRCC PACS-2 marine sediment CRM. The estimated limit of detection is 12ng/g. The proposed procedure was applied to the analysis of a real sediment core sampled to a depth of 160m in Lake Como, where Hg concentrations ranged from 66 to 750ng/g.

Preserved memory in temporal lobe epilepsy patients after surgery for low-grade tumour. A pilot study.

The objective was to carry out a pilot study exploring memory outcome in patients with temporal lobe epilepsy (TLE) and low-grade tumour. A prospective study using a competence-related memory assessment was carried out in the Laboratory of Neuropsychology, Epilepsy Center and Neurosurgical Department of the "C. Besta" National Neurological Institute in 24 TLE patients undergoing surgical resection for left (n=12) or right (n=12) low-grade tumours and 36 healthy subjects. Patients underwent mesial or lateral temporal lobe lesionectomy. Neuropsychological tests exploring verbal and visual short-term memory, learning, delayed recall and ability to control interference in memory were applied. Before and after surgery, significant verbal impairment was present in left TLE patients compared to controls and right TLE patients, and visual deficits were present in both groups compared to controls. After surgery, there was no significant decrease in mean verbal or visual memory scores related to the operated side. Some memory abilities subserved by the contralateral temporal lobe improved. Postoperative memory scores were related to preoperative scores, side of operation, age and education. In patients with TLE and low-grade tumour, temporal lobe surgery does not necessarily induce memory deficits. Improvement of memory abilities subserved by the unoperated temporal lobe may be expected.

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.

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.

Early surgery of ruptured anterior circulation aneurysm based on multislice helical computerised tomography angiography.

The purpose of this study is to evaluate the utility of three-dimensional computed tomographic angiography (3D-CTA) as the primary diagnostic investigation in patients with spontaneous subarachnoid haemorrhage (SAH) from anterior circulation aneurysms, and to correlate the results with digital subtraction angiography (DSA) and intraoperative findings. From May 2005 to May 2007 a total of 38 consecutive patients admitted for SAH, suspicious for ruptured anterior circulation cerebral aneurysm, underwent 3D-CTA. Inclusion criteria were a SAH confirmed by a non-contrast head computed tomographic scan or by lumbar puncture. Exclusion criteria were: previous DSA, severe contrast medium allergy and severe renal failure. All patients underwent early surgical clipping of the aneurysm. The mean time between SAH onset and surgery was 43.6 h (range, 14-74 h). The 3D-CTA was performed in all cases; and in 13 out of 38 patients (34%) represented the only preoperative exam. In all patients that underwent surgery with the sole 3D-CTA, the images collected allowed a good visualisation of the morphology of aneurysms and of the anatomical relationship with the vascular structures. 3D-CTA allows accurate diagnosis with an excellent visualisation of ruptured aneurysms of the anterior circulation. Our results suggest that, in selected cases, ruptured anterior circulation aneurysms could be successfully treated on the basis of 3D-CTA alone.

Iatrogenic intracranial pseudoaneurysms: neuroradiological and therapeutical considerations, including endovascular options.

Intracranial pseudoaneurysms represent a potentially fatal complication of intracranial surgery. Our purpose is to describe their neuroradiological characteristics, prognostic features and possible treatment. Eight cases of postsurgical intracranial pseudoaneurysms have been observed at our institution since 1988. Four were observed following transsphenoidal (TS) surgery and four after pterional craniotomies. Two types of iatrogenic pseudoaneurysms were observed: "fusiform", probably due to weakening of the adventitia during surgical peeling of the tumour from the artery (three cases) and "saccular", occurring after a more focal or complete laceration of the vessel (five cases), more often after TS surgery. A thorough preoperative neuroradiological examination may identify anatomical conditions at risk for development of this severe complication. Postoperative neuroradiological follow-up is mandatory in cases in which unusual bleeding has occurred during the perioperative period, but absence of bleeding does not exclude the possible development of a pseudoaneurysm. Endovascular treatment of pseudoaneurysms represents a safe and durable procedure, specifically in those cases in which damage to the carotid siphon occurred during TS surgery.

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.

Diagnostic imaging in 13 cases of Rasmussen's encephalitis: can early MRI suggest the diagnosis?

Rasmussen's encephalitis (RE) is a rare, progressive, chronic encephalitis characterised by drug-resistant epilepsy, progressive hemiparesis and mental impairment. It typically involves only one cerebral hemisphere, which becomes atrophic. We present neuroradiological findings in 13 children with RE. MRI was performed in all patients, fluorodeoxyglucose positron-emission tomography (PET) in three, Tc-99m hexamethylpropylenamine oxime single-photon emission computed tomography (SPECT) in two and proton MR spectroscopy ((1)HMRS) in two. MRI showed progression of the hemisphere atrophy, always prevalent in the region primarily involved (13 patients), spread of the abnormal signal in white matter (11) and cortex (10) and progression of atrophy of the head of the caudate nucleus (nine). Associated secondary changes were: atrophy of the contralateral cerebellar hemisphere (in four patients), the ipsilateral hippocampus (in five) and the brain stem (in five). The earliest CT and MRI abnormalities, seen between 1 day and 4 months after the first seizure (in 12 patients examined, nine of whom had MRI) in one cerebral hemisphere included: high signal on T2-weighted images in the cortex (seven patients) and white matter (nine), cortical atrophy usually involving the frontoinsular region, with mild or severe enlargement of the lateral ventricle (eight) and moderate atrophy of the head of the caudate nucleus (seven). Cortical swelling in the early stage of the disease was recognisable only in two patients. PET revealed hypometabolism, SPECT decreased perfusion, and (1)HMRS reduction of N-acetylaspartate in the affected hemisphere. PET and SPECT were usually performed in the late stages and did not provide specific findings. MRI thus demonstrates the progression of RE and may suggest the diagnosis in the early stages, often before the appearance of neurological deficits. Early diagnosis of RE may be crucial for selecting patients for aggressive medical therapy or major surgical interventions such as hemispherectomy.

Aneurysms of the posterior cerebral artery: classification and endovascular treatment.

BACKGROUND AND PURPOSE: We present a retrospective review of our experience in the endovascular treatment of posterior cerebral artery (PCA) aneurysms. We detail the anatomic location of these aneurysms, the technique of endovascular treatment, morphologic results, and clinical outcome. We also discuss the segmental anatomy of the PCA as it relates to the various neurologic deficits that may result from occlusion of the parent artery. METHODS: From 1993 to 1998, 20 patients (12 female, eight male; mean age, 44 yrs) harboring a PCA aneurysm were treated via an endovascular approach. One patient had two aneurysms, comprising a total of 21 lesions. Fourteen (66%) of 21 aneurysms were saccular in nature, five (24%) were giant serpentine aneurysms, and two (10%) were posttraumatic. All aneurysms were treated using Guglielmi detachable coils (GDC) either by selective obliteration of the aneurysm sac or by parent artery occlusion. RESULTS: Fourteen (66%) of the 21 aneurysms were successfully treated with preservation of the parent artery. In the remaining seven (33%), the parent artery was permanently occluded. The overall complication rate in this series was 15%, with a permanent morbidity rate of 10% and a 0% mortality rate. CONCLUSION: Aneurysms of the PCA are rare compared with other locations in the intracranial circulation. Saccular PCA aneurysms can be treated effectively, by use of GDC, to obliterate the aneurysm yet preserve the parent artery. Fusiform and giant serpentine aneurysms of the PCA can effectively be treated by permanent occlusion of the parent artery; in these cases, thorough knowledge of the PCA segmental anatomy is crucial in order to select the site of occlusion and to avoid major neurologic deficits.

Pigment villonodular synovitis of the spine. Case report and review of the literature.

Pigmented villonodular synovitis (PVNS) is a disease of the joints which uncommonly involves the spine. We present a 70-year-old woman with radicular symptoms who was found to have a mass arising from a lumbar zygapophyseal joint with extension into the spinal canal. Following gross-total excision of the mass, histology revealed PVNS. One month after surgery, the patient had no symptoms and there was no evidence of residual or recurrent disease.

Congenital muscular dystrophy with merosin deficiency: MRI findings in five patients.

We present the MRI findings in five patients with congenital muscular dystrophy (CMD) and merosin (laminin alpha2) deficiency, which was total in one and partial in four. In one patient with partial merosin deficiency, MRI was normal. The other four patients had supratentorial white matter abnormalities. In three, T2-weighted images revealed subcortical, deep lobar and periventricular high signal in white matter, while in the other there were only small peritrigonal areas of increased signal. On T1-weighted images, there was slightly low signal. Cortical abnormalities were absent. None of these changes were accompanied by symptoms or signs of central nervous system involvement. White matter abnormalities in a patient with CMD should prompt investigation of merosin.

Mitochondrial disease associated with the T8993G mutation of the mitochondrial ATPase 6 gene: a clinical, biochemical, and molecular study in six families.

AIM: To contribute to the establishment of a rational clinical, neuroradiological, and molecular approach to neurogenic muscle weakness, ataxia, and retinitis pigmentosa (NARP) and maternally inherited Leigh's syndrome (MILS). METHODS AND RESULTS: The T8993G mutation in the mitochondrial genome was found in several maternal members of six pedigrees, whose clinical status ranged from no symptoms to severe infantile subacute necrotising encephalomyelopathy (Leigh's disease). In one case a MELAS-like syndrome was documented both clinically and neuroradiologically. Relevant genetic features of the series were anticipation of symptoms through subsequent generations, and the presence of several cases in whom the mutation apparently occurred recently or was new. A uniform distribution of the mutation in many tissues was shown in one patient subjected to necropsy. In general, a good correlation was found between clinical severity and mutation heteroplasmy in readily accessible tissues, such as lymphocytes or fibroblasts. By contrast, a consistent reduction of the mitochondrial ATPase activity, to about half of the normal values, was found in most of the clinically affected cases, irrespective of the amount of mutant mitochondrial DNA. CONCLUSIONS: Although the measurement of ATP hydrolysis in cultured fibroblasts was a reliable, and sometimes instrumental, means to identify T8993G positive patients, the relation between the mutation and the oxidative phosphorylation defect is probably very complex, and its understanding requires more complex biochemical analysis.

Lesionectomy in epileptogenic temporal lobe lesions: preoperative seizure course and postoperative outcome.

A series of 54 patients operated on for temporal epileptogenic lesions is reported: 36 had slow growing tumours, 18 supratentorial cavernous angiomas. The patients were divided into two different groups according to the presence of seizures controlled (group 1) or not controlled (group 2) by antiepileptic drugs (AEDs). All the patients underwent preoperative scalp EEG and magnetic resonance imaging (MRI). They were operated on by pure lesionectomy, associated with amygdalo-hippocampectomy in 8 cases of uncontrolled seizures. Postoperatively they underwent MRI examination which revealed an incomplete lesionectomy in 12 cases. Patients were followed up after surgery for at least 2 years, 6 of them were reoperated on for the persistence (or regrowth) of the tumour. The results of epilepsy outcome are reported. These cases underline the importance of preoperative electroclinical study, in order to determine the relationship between lesion location and epileptic focus. If good concordance is present, a complete lesionectomy is enough to cure the patient. In other cases associated amygdalo-hippocampectomy leads to better results, while more complicated cases may need preoperative stereo-EEG studies.