Considerations about Occlusion of the Intracranial Distal Internal Carotid Artery.

Occlusion of the intracranial distal internal carotid artery (ICA) is one of the most critical conditions among the cases of acute stroke in the anterior circulation. The introduction of selective endovascular treatment first using thrombolytic agents replaced later by the mechanical thrombectomy using various devices has improved the prognosis in a certain number of these patients. Among the factors influencing the prognosis of these patients, one is the collateral circulation which in these cases is mainly characterized by leptomeningeal anastomoses. The collateral can, however, be impaired, by distal embolization and by anomalies of the Circle of Willis: the aim of this study is to describe these aspects.

A family with autosomal dominant leukodystrophy linked to 5q23.2-q23.3 without lamin B1 mutations.

BACKGROUND AND PURPOSE: Duplications of lamin B1 (LMNB1) at 5q23 are implicated in adult-onset autosomal dominant leukodystrophy (ADLD) having been described in six families with diverse ethnic background but with a homogeneous phenotype. In a large Italian family, we recently identified a variant form of ADLD characterized clinically by absence of the autonomic dysfunction at onset described in ADLD and, on MRI, by milder cerebellar involvement with sparing of hemispheric white matter. Aim of this study was to investigate the genetic basis of this variant form of ADLD. METHODS: We carried out a genome-wide linkage analysis using microsatellite markers, and the genes in the candidate region were screened for point mutations. LMNB1 was also screened for deletions/duplications by real-time PCR, multiplex ligation-dependent probe amplification and Southern blot. RESULTS: We mapped the variant ADLD locus to 5q23.2-q23.3, a genomic region containing 11 genes including LMNB1. Neither gene copy-number defects nor point mutations in the LMNB1 gene were found. We also excluded point mutations in the coding exons of the other ten genes in the candidate region. However, expression of lamin B1 evaluated in lymphoblastoid cells was higher in patients than in healthy controls, and was similar to the lamin B1 expression levels found in a patient with LMNB1 duplication. CONCLUSIONS: This observation suggests that a mutation in an LMNB1 regulatory sequence underlies the variant ADLD phenotype. Thus, adult forms of ADLD linked to 5q23 appear to be more heterogeneous clinically and genetically than previously thought.

Lacunes and other holes: diagnosis, pathogenesis, therapy.

Lacunar ischemic lesions are related to a pathology involving perforators, due to direct changes in the arteries or to an indirect mechanism, such as cardiac or artery to artery embolism, or to hypoperfusion in cases of cardiac failure, or proximal occlusion of large arteries. Changes involving the large intracranial arteries have progressively been taken into consideration as a cause of the disease. This latter aspect is interesting since possible endovascular treatment can be proposed in selected cases. In patients with lacunar syndrome an extended clinical and neuroradiological approach is indicated to choose the most appropriate therapy. Not all lesions recognizable on CT/MR are the expressions of ischemic lesions, this is another important aspect that should be considered in the differential diagnosis.

Paediatric dissecting aneurysm of the posterior cerebral artery:.case report and review of the literature.

SUMMARY: Aneurysms in children are rare.We describe a large spontaneous dissecting aneurysm of the posterior cerebral artery. The clinical presentation was characterized by headache as the sole symptom due to a mass effect leading to hydrocephalus. Acute treatment with a temporary ventricular shunt was followed by occlusion of the aneurysm via an endovascular approach leading to a complete recovery of the patient.

Atherosclerotic adult Moya-Moya disease in a patient with hyperhomocysteinaemia.

Moya-Moya is a rare cerebrovascular occlusive disease characterized by bilateral stenosis or occlusion at the terminal portion of the internal carotid artery and abnormal vascular network at the base of the brain, named "moya-moya". In children, Moya-Moya disease usually presents with ischemic cerebrovascular events, mainly TIA or lacunar stroke, leading to mental deterioration. In adults, especially in females, it presents with intracranial haemorrhages. We describe the case of an adult patient with an atherosclerotic Moya-Moya disease which presented with a cerebral borderzone infarction.

Periprocedural morbidity and mortality by endovascular treatment of cerebral aneurysms with GDC: a retrospective 12-year experience of a single center.

Despite increasing experience and improved material, endovascular treatment of cerebral aneurysms still has risks linked to the technique itself and to the specificity of the pathology treated. The purpose of this report is to examine procedural technical and clinical negative events, even minimal ones, occurring in this type of treatment. We considered 557 procedures carried out from January 1994 to December 2005 in 533 patients harboring 550 aneurysms. Of the patients, 448 presented with SAH and 85 with unruptured aneurysms. All procedures were performed under general anesthesia. The GDC-10 system was routinely used. Additional devices like the balloon remodeling technique, Trispan and stents were also occasionally used. Every procedural complication occurring during or soon after treatment was registered. Endovascular treatment was completed in 539 out of 557 procedures. There were 18 failures (3.3%). Occlusion of the aneurysm was judged complete in 343 (64%), near complete in 184 (34%) and incomplete in 12 (2%). Procedural complications occurred in 72 (13%) of the cases. The most frequent negative events were thromboembolisms (6.6%) and ruptures (3.9%). Other types (coil migration, transient occlusions of the parent vessel, dissections and early rebleeding) were rarer (2.5%). In the majority of cases there were no clinical consequences. Procedural morbidity and mortality were 1.1 and 1.8%, respectively. Considering the 449 procedures performed in ruptured and the 90 in the unruptured aneurysms separately, morbidity and mortality were 1.1 and 2.2% in the former group and 1.1 and 0% in the latter. Many factors influence the risk of complications. Being progressively aware of this and with increasing experience, the frequency can be limited. Negative events linked to the procedure have more significant serious clinical consequences in patients admitted in a critical clinical condition after SAH, because of the already present changes involving the brain parenchyma and cerebral circulation.

Functional MR study of a motor task and the tower of London task at 1.0 T.

INTRODUCTION: The use of functional magnetic resonance imaging (fMRI) for clinical applications and basic neuroscience is constantly increasing. The discussion about minimum performance requirement for a correct implementation of fMRI is still open, and one of the critical points is the magnetic field strength. We tested the feasibility of fMRI at 1.0 T during motor and cognitive tasks. METHODS: Fourteen healthy subjects were scanned during a motor task and 12 while performing the Tower of London task. In the activated areas, the percentage signal change due to BOLD (blood oxygenation level dependent) contrast was analysed. To check basic image quality of the acquisition system we measured quality indices in a temporal series of images of a phantom. RESULTS: Motor and cognitive brain activations matched previous results obtained at higher field strengths. The mean percentage change over subjects in the motor task was in the range 1.3-2.6% for the primary motor area and 0.8-6.7% for the cerebellum. In the cognitive task, the mean percentage change over subjects was 0.7-1.2% for a frontal area and 0.6-2.8% for a parietal area. The percentage noise of the phantom temporal series was less than 0.4%. Percentage changes and signal to noise ratio, although lower than that obtained with high-field systems, allowed activation maps to be obtained in all subjects. CONCLUSION: Our results replicate previous fMRI results demonstrating reproducible motor-related brain activations and extend the field to a complex cognitive task, thus providing evidence of the safety for routine clinical use of 1-T equipment.

The effect of gender on planning: An fMRI study using the Tower of London task.

Since the introduction of brain mapping, evidences of functional gender differences have been corroborating previous behavioral and neuropsychological results showing a sex-specific brain organization. We investigated gender differences in brain activation during the performance of the Tower of London (TOL) task which is a standardized test to assess executive functions. Eighteen healthy subjects (9 females and 9 males) underwent fMRI scanning while solving a series of TOL problems with different levels of difficulty. Data were analyzed by modeling both genders and difficulty task load. Task-elicited brain activations comprised a bilateral fronto-parietal network, common to both genders; within this network, females activated more than males in dorsolateral prefrontal cortex (DLPFC) and right parietal cortex, whereas males showed higher activity in precuneus. A prominent parietal activity was found at low level of difficulty while, with heavier task demand, several frontal regions and subcortical structures were recruited. Our results suggest peculiar gender strategies, with males relying more on visuospatial abilities and females on executive processing.

Endovascular treatment of cerebral aneurysms in elderly patients.

We report our experience in the endovascular treatment with detachable platinum coils of ruptured or symptomatic unruptured cerebral aneurysms in 61 patients aged 70-82 years. Complete occlusion was achieved in 38, subtotal in 17 and partial in one. The treatment failed in five patients. Clinical follow-up was performed in all patients for 8 months to 8 years. No bleeding occurred during the follow-up period. Outcome was favourable in 63% of the patients. When we compared the outcome of elderly patients with those of younger age endovascularly treated in the same period of time, we found a significantly higher frequency of poorer outcome in the elderly group (chi(2) = 9.084; P = 0.011). The frequency of favourable outcome in the elderly was significantly lower than in the younger group for H-H IV-V (chi(2) = 9.299; P = 0.010). The most important factor influencing the outcome was not age itself, but primary clinical condition on admission. The therapy of symptomatic aneurysms in elderly patients should not be purely conservative--a direct approach of the aneurysm should be considered. Endovascular treatment whenever possible seems to be a good alternative to surgery.

Endovascular treatment of the posterior inferior cerebellar artery aneurysms.

Aneurysms may arise at various locations along the course of the posterior inferior cerebellar artery. Brainstem and cranial nerves manipulation make the surgical approach to proximal aneurysms difficult, while the occlusion of the parent vessel is sometimes unavoidable in peripheral aneurysms. Endovascular treatment can be a good alternative, but also with this approach the location of the aneurysm is critical. If occlusion of the parent vessel is planned, anatomical variations and vascular territories of the brainstem should be considered. We report our experience with 18 consecutive aneurysms (12 proximal, 6 peripheral) treated by coils. Complete occlusion was achieved in 14 patients and subtotal in 4. In three patients the parent vessel had to be sacrificed. During treatment two perforations occurred; aneurysms were completely occluded without clinical consequences. Two small asymptomatic cerebellar infarctions were seen on postoperative computed tomography. Clinical outcome was good in 16 patients.

Acute endovascular treatment of ruptured aneurysms in poor-grade patients.

We reviewed the 6-month outcome of 45 consecutive patients in poor grade treated acutely by coiling after subarachnoid haemorrhage (SAH). About half had a favourable outcome, a promising result in accordance with some surgical and endovascular reports proposing early aggressive treatment of an aneurysm causing SAH. The poor clinical grade, due to parenchyma damage from the SAH, remains the main prognostic factor, rebleeding from the untreated aneurysm being only one cause of poor outcome. It is therefore difficult to isolate the impact of any treatment of the aneurysm on outcome, and unavoidable selection bias may strongly influence favourable results. Nevertheless, available evidence and the limited invasiveness suggest that acute endovascular treatment is reasonable in these patients.

Progressive multifocal leukoencephalopathy: diffusion-weighted imaging and pathological correlations.

We examined MRI of two patients with progressive multifocal leukoencephalopathy (PML), including diffusion-weighted imaging (DWI), with calculation of apparent diffusion coefficients (ADC). The pathology findings of one patient were compared with those of MRI. The lesions had different ADC and DWI appearances, depending on the stage of the disease. Newer lesions and the advancing edge of large lesions had normal-to-low ADC and gave high signal on DWI. Older lesions and the centre of large lesions had increased ADC and gave low signal. High signal on DWI and low ADC mark the regions of active infection and cell swelling, distinguishing them from areas of reparative gliosis.

Extensive cortical damage in a case of Creutzfeldt-Jacob disease: clinicoradiological correlations.

MRI demonstrated extensive cortical involvement in a patient with pathologically proven Creutzfeldt-Jacob disease. The whole brain was atrophic; some of the supratentorial cortex, putamen and caudate nucleus gave high signal on T2-weighted images; the changes were more extensive on diffusion-weighted images (DWI). Comparison of the history, and the sites of atrophy and signal change suggested that the latter predominates in regions with long-lasting damage and prevalent gliosis, while high signal on DWI indicate current neuronal loss. This case widens the range of MRI findings in patients with Creutzfeldt-Jacob disease, and suggests that some information about the progression of the disease can be extracted from single MRI study.

Diffusion-weighted images of intracranial cyst-like lesions.

Magnetic resonance sequences may be designed to evaluate the diffusion movements of the protons (diffusion-weighted images, DWI). In these images, a bright signal identifies a region where the diffusion along a spatial axis is restricted. The contents of a cystic lesion frequently have the signal intensities of a generic homogeneous hyperproteinic fluid (hypointensity in T1-, hyperintensity in T2-weighted images). DWI may give further information about the microscopic organisation of these fluids: a hyperintense signal indicates the presence of a restricted diffusion, due to some kind of microscopic organisation, at the cellular or macromolecular level. This may provide additional information useful for clinical purposes. We obtained DWI in 24 consecutive patients with intracranial cystic lesions, (19 intra-axial: five abscesses, five gliomas, six metastases, two demyelinating lesions, one neurocysticercosis; five extraaxial: two arachnoid cysts, two epidermoid cysts, one cholesteatoma). We found a strongly hyperintense signal, indicating restricted diffusion, in brain abscesses, epidermoid cysts and cholesteatoma; all the remaining lesions were hypointense or mildly hyperintense. We found these data useful in critical diagnoses, such as in differentiating abscesses from tumours, and in identifying elusive tumours such as epidermoid cysts.

[Check of compliance with quality criteria for diagnostic radiographic images in quality control]. / Verifica del rispetto dei livelli diagnostici di riferimento nella radiodiagnostica nell'ambito dei controlli programmati della qualità.

PURPOSE: To devise and implement a programme of measurements to assess the entrance surface dose for a standard-sized patient and to check the compliance with diagnostic reference levels. MATERIAL AND METHODS: Dose evaluation was performed on 40 radiographic instruments. The exposure parameters were collected for the main radiographic procedures (chest, skull, spine, pelvis, abdomen) each performed with instrument on a standard-sized patient. The output of each X-ray tube at 70, 80, 90, 100, 110 and 120 kV was measured with a solid state detector during quality controls. Beam quality and geometric characteristics of the equipment were also determined. The entrance surface dose for a standard patient was assessed for each procedure carried out with the 40 instruments, thus obtaining a total of 155 radiographic techniques. Finally, the method was validated by comparing the values obtained with the solid state and an ionization chamber for X-ray beam detector. RESULTS: The comparison between the solid state detector and the ionisation chamber demonstrated a good agreement. Results show that reference diagnostic levels are respected in most examinations (147/155) even if exposure values do not always comply with those indicated by European guidelines. The measurement programme seems to be applicable in hospital practice where the large number of radiographics instruments and procedures requires the acquisition and processing of a large number of data. CONCLUSIONS: The evaluation of patient dose during quality control is feasible and allows a first check of compliance with reference levels in order to identify which procedures can be optimised by means of more specific measurements and assessments.

Primitive cerebral melanoma: case report and review of the literature.

BACKGROUND: Central nervous system primary malignant melanoma accounts for approximately 1% of all the cases of melanoma; reports in the literature are relatively rare. CASE DESCRIPTION: A 74-year-old man was hospitalized because of an episode of aphasia. The neuroradiologic examinations demonstrated a round homogeneous lesion extending near the left sylvian fissure. He had no extracranial abnormalities. The patient underwent a neurosurgical procedure and the tumor was macroscopically totally excised. Pathological examination of the surgical specimen revealed a histological appearance similar to that of melanoma. A diagnosis of primary CNS melanoma was made after careful dermatologic and ophthalmologic examination, which ruled out presence of cutaneous or choroidal melanoma. The patient did not receive any further treatment and he is free of disease 2 years after diagnosis. CONCLUSIONS: We report a case of primary cerebral melanoma of the left temporal lobe; clinical, neuroradiological, and histological findings are discussed with review of the literature. Primary melanoma of the CNS may present either with localized intra/extra-axial mass lesions or with meningeal spread, which carries a worse prognosis. The prognosis of cerebral primitive melanoma is variable, although it is common opinion that primitive cerebral melanoma has a better prognosis than cutaneous melanoma, with two cases in the literature surviving 9 and 12 years.

Diffusion-weighted MR in reversible wernicke encephalopathy.

Diffusion-weighted images (DWI) of a patient with Wernicke encephalopathy were obtained during routine MR examination. Mammillary bodies were hyperintense on T2-weighted and enhanced on T1-weighted images; on DWI, a mild hyperintensity was noticed. Calculation of the apparent diffusion coefficient (ADC) demonstrated an increased diffusion on the affected regions; the hyperintensity on DWI was probably due to a "T2-shine-through" effect. These findings are consistent with the presence of extracellular oedema, without significant neuronal damage. The patient recovered promptly after thiamine administration, and MR alterations disappeared. The favourable evolution indicates that no relevant neuronal death occurred. This is consistent with DWI findings. DWI are more sensitive than ordinary T1- and T2-weighted images to neuronal irreversible damage, and may differentiate between neuronal necrosis and extracellular oedema in various brain pathologies. The demonstration of a limited neuronal damage may represent a favourable prognostic factor in patients with WE.