Circle of Willis: anatomical variations of configuration. A magnetic resonance angiography study.

BACKGROUND: The main scope of this paper is to investigate the prevalence of the anatomical variants of the circle of Willis (CoW) in the Romanian population through magnetic resonance angiography. MATERIALS AND METHODS: Magnetic resonance angiography images were obtained for 126 individuals and the configurations of the anterior and posterior CoW were identified, and classified. The prevalence of each variant and the number of complete anterior or posterior parts of the circle were determined. RESULTS: A classical configuration of the CoW was found in 39 (30.9%) cases. The most common posterior variation was the unilateral absence of a posterior communicating artery (n = 28) while in the anterior circle it was the unilateral absence of the precommunicating segment of an anterior cerebral artery (n = 17). A complete entire CoW was found in 63 cases, while the anterior and posterior parts yielded complete configurations in 108 and 73 cases, respectively. Eight cases did not present complete configurations. A foetal posterior communicating artery was identified unilaterally in 14 cases and bilaterally in 6 cases. CONCLUSIONS: Unilateral variations were the most common changes found in CoW configuration. The correct assessment of the CoW configuration may prove useful in the planning and follow-up of brain surgery and interventional procedures, as well as in estimating the prognosis of patients suffering from stroke or other related cerebral vascular events.

Carotid paragangliomas: case report and imaging review.

BACKGROUND: Presentation of case reviews depicting the imaging characteristics of carotid paragangliomas, associated with a thorough analysis of the anatomical morphological features and the current therapeutic strategies. MATERIALS AND METHODS: We present the cases of 3 patients diagnosed with carotid paragangliomas in our clinic, illustrating diagnostic imaging elements by computer tomography (CT) and magnetic resonance imaging (MRI), but also the postoperative aspect of the carotid system, with respective anatomical, clinical and surgical considerations. RESULTS: The imaging aspect of the carotid paragangliomas is characterised by a mass of soft tissue with intense contrast enhancement and with "salt and pepper" MRI appearance on conventional spin-echo sequences. The postoperative evolution of the patients included in the article was favourable, without any perioperative complications or signs of local tumour recurrence. CONCLUSIONS: Carotid paragangliomas are rare, often asymptomatic tumours, but with potential for increased malignancy, which raises the need for good knowledge of the cervical region pathology as well as the features of neuroendocrine tumours. CT and MRI examinations are essential for diagnosis, staging and, implicitly, for establishing the therapeutic strategy.

Persistent repeated measurements by magnetic resonance spectroscopy demonstrate minimal hepatic encephalopathy: a case report.

Minimal Hepatic Encephalopathy (MHE), previously referred to as infraclinical or subclinical is a precursor in the development of clinical hepatic encephalopathy (HE). The demonstration of MHE is done through neuropsychological testing in the absence of clinical evidence of HE, patients showing only a mild cognitive impairment. Neuropsychological tests employed consist of Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and portosystemic encephalopathy (PSE) test score. Unfortunately, there are numerous occasions when the tests prove irrelevant: in the situation of inexperienced investigators, the patient's poor education, vision problems or concurring central nervous system disease, all of which may delay or deviate from the correct diagnosis.

Endovascular minimally invasive treatment of the intracranial aneurysms--first 124 cases.

INTRODUCTION: Since May 2005, we have started to treat the intracranial aneurysms endovascular way as an alternative minimally invasive technique to the classic neurosurgery treatment. OBJECTIVE: Studying the patients' demographics, clinical presentation, aneurysm size and configuration, type of coils used for embolization, the percentage of compaction and recanalization (especially in patients who presented with subarachnoid hemorrhage), and immediate complications. METHODS AND RESULTS: An all-inclusive retrospective review of every patient who underwent coils embolization (stent or balloon assisted included) of saccular aneurysms from May 2005 to September 2011 was performed. A total of 116 patients (46 men and 60 women) and 124 aneurysms were treated. A total of 96 patients (41 men and 55 women) underwent follow-up femoral cerebral angiograms (mean follow-up was 25 months and the longest was at 37 months). Five patients required intra-arterial abciximab due to thrombus formation. Four patients had aneurysm rupture while the coil was being advanced. Eleven patients were treated during vasospasm peak. Seven patients had recanalization at 12 months follow-up. DISCUSSION: The average hospitalization period was of 4 days. There is a close relation between Hunt and Hess scale score before treatment and post interventional neurological status. Due to subarachnoid hemorrhage, the vasospasm remains a threat to the patient's neurological status. The treatment of cerebral aneurysms with endosacular embolization by coils is a safe and durable option. The risk of recanalization or re-rupture in our cohort is small compared to series published elsewhere. Larger series of patients are needed to support our evidence.

Updates in MRI characterization of the thymus in myasthenic patients.

PURPOSE: To evaluate the imaging appearance of the thymus in the myasthenic patients by using chemical shift magnetic resonance imaging, and, to correlate the chemical shift ratio (CSR) with pathologic findings after surgical excision. MATERIALS AND METHODS: In the past year, a total of 11 myasthenic patients (4 males, 7 females; age range of 26-65 years), have been investigated by MRI centered at the thymic lodge. Our protocol included a Dual-Echo technique, T1-weighted In-phase/Opposed-phase MR images in all patients. A chemical shift ratio (CSR) was calculated by comparing the signal intensity of the thymus gland with that of the chest wall muscle for quantitative analysis. For this purpose, we have used standard region-of-interest electronic cursors at a slice level of the maximum axial surface of the thymus. We have identified two patients groups: a thymic hyperplasia group and a thymic tumoral group. RESULTS: With the decrease in the signal intensity of the thymus gland at chemical shift, the MR imaging was evident only in the hyperplasia group. The mean CSR in the hyperplasia group was considerably lower than that in the tumor group, 0,4964 ± 0,1841, compared with 1,0398 ± 0,0244. The difference in CSR between the hyperplasia and tumor groups was statistically significant (P=0,0028). CONCLUSION: MR imaging using T1-weighted In-phase/Opposed-phase images could be a useful diagnostic tool in the preoperative assessment of the thymic lodge and may help differentiate thymic hyperplasia from tumors of the thymus gland.

Magnetic resonance spectroscopy--a non-invasive method in evaluating focal and diffuse central nervous system disease.

Magnetic Resonance Spectroscopy is a non-invasive method, which can be performed following a routine Magnetic Resonance investigation within the same examination, and can provide very useful molecular information related to the metabolism and function of the normal and pathological structures of the brain. Its role is increasing in the establishment of a clear diagnosis, in both focal and diffuse central nervous system diseases, and the tendency is to replace the histopathology test, in certain cases, with similar or sometimes better diagnostic accuracy. This paper summarizes the principle, method, and main clinical applications, standing as a guide to procedure performing and results interpretation.

The management of the bilateral internal carotid dissection clinical case presentation.

Introduction:We present the case of a 36-year-old patient who was treated in the National Institute of Neurology and Cerebrovascular Diseases in Bucharest - in the neurology and the imagistic departments - for bilateral carotid dissection. Goals: The main goal of this article was to discover the cause that lead to the symptoms of the patient using MRI and angio-MRI.In the process,we tried to dilate the stenosis (due to dissection) on 2 internal carotid arteries by using stents in order to keep the true lumen open. Methods:In order to make a diagnosis we used the Magnetic resonance imaging machine (MRI) (1,5 T from GE), the multislice Computer Tomography (CT) scan (16 detectors from Siemens) and the digital substraction angiography (Siemens Axiom Artis). In addition, we used the same angiography machine for the endovascular procedure. The stents that we used were Wallstents from Boston Scientific Company. Results: The patient left the hospital having a NIHSS=10, with dysarthria and left hemiplegia that were 80% recovered after 2 months. Discussion: The particularity of this case study is the spontaneous bilateral internal carotid dissection. The second dissection might have resulted in being also iatrogenic, due to several attempts of stenting the first one. Conclusions: The successful treatment of this patient was the result of the collaboration between the neurology and neuroradiology departments.The first therapeutic option in carotid dissection has to be stenting, under certain conditions.

The thymus in myasthenic patients: correlation between mediastinal CT imaging and histopathological findings.

PURPOSE: To correlate computed tomographic (CT) appearance of the thymus with results from histologic examination of thymic tissue in myasthenic patients who underwent thymectomy. MATERIALS AND METHODS: A retrospective study, based on case series report, between January 2000 and December 2010 on 247 patients with generalized myasthenia gravis or myasthenic syndrome explored by CT using a specific protocol, in the Radiology and Medical Imaging Department of Fundeni Clinical Institute. All subjects in the study were operated and had a histologic evaluation. RESULTS: CT examinations of these 247 subjects showed remaining thymic mass, remnant of thymic tissue, fatty infiltration of the thymus and tumoral thymus or focal thymic mass. The results of histologic examination showed normal thymus, thymic lymphoid follicular hyperplasia, thymic atrophy, fatty infiltration and thymoma. CONCLUSION: It was a 100% correlation between CT examinations and intra-operative findings regarding the presents of focal thymic masses in our study. In the diagnostic of focal thymic mass, the only inter-disciplinary correlation is between radiological and macroscopic aspects. CT examination has a limited value in differential diagnosis between thymic lymphoid follicular hyperplasia and thymoma.