[Basal ganglia calcification]. / Calcifications des noyaux gris centraux.

Calcifications of the basal ganglia are frequently seen on the cerebral CT scans and particularly in the globus pallidus. Their frequency increases physiologically with age after 50 years old. However, pathological processes can also be associated with calcium deposits in the gray nuclei, posterior fossa or white matter. Unilateral calcification is often related to an acquired origin whereas bilateral ones are mostly linked to an acquired or genetic origin that will be sought after eliminating a perturbation of phosphocalcic metabolism. In pathological contexts, these calcifications may be accompanied by neurological symptoms related to the underlying disease: Parkinson's syndrome, psychiatric and cognitive disorders, epilepsy or headache. The purpose of this article is to provide a diagnostic aid, in addition to clinical and biology, through the analysis of calcification topography and the study of different MRI sequences.

Inaugural tumor-like multiple sclerosis: clinical presentation and medium-term outcome in 87 patients.

BACKGROUND: Tumefactive demyelinating lesions of the central nervous system can be the initial presentation in various pathological entities [multiple sclerosis (the most common), Balo's concentric sclerosis, Schilder's disease and acute disseminated encephalomyelitis] with overlapping clinical presentation. The aim of our study was to better characterize these patients. METHODS: Eighty-seven patients (62 women and 25 men) from different MS centers in France were studied retrospectively. Inclusion criteria were (1) a first clinical event (2) MRI showing one or more large demyelinating lesions (20 mm or more in diameter) with mass-like features. Patients with a previous demyelinating event (i.e. confirmed multiple sclerosis) were excluded. RESULTS: Mean age at onset was 26 years. The most common initial symptoms (67% of the patients) were hemiparesis or hemiplegia. Aphasia, headache and cognitive disturbances (i.e. atypical symptoms for demyelinating diseases) were observed in 15, 18 and 15% of patients, respectively. The mean largest diameter of the tumefactive lesions was 26.9 mm, with gadolinium enhancement in 66 patients (81%). Twenty-one patients (24%) had a single tumefactive lesion. During follow-up (median time 5.7 years) 4 patients died, 70 patients improved or remained stable and 12 worsened. 86% of patients received initial corticosteroid treatment, and 73% received disease-modifying therapy subsequently. EDSS at the end of the follow-up was 2.4 ± 2.6 (mean ± SD). CONCLUSION: This study provides further evidence that the clinical course of MS presenting with large focal tumor-like lesions does not differ from that of classical relapsing-remitting MS, once the noisy first relapsing occurred.

A quantitative and semi-automatic measurement of transverse sinus stenosis improves idiopathic intracranial hypertension diagnostic accuracy.

We propose a new reliable transverse sinus stenosis (TSS) index based on magnetic resonance venography (MRV) for the diagnosis of idiopathic intracranial hypertension (IIH). Our quantitative semi-automatic measurement analysis based on segmentation and cross-sectional TS diameter from 48 IIH patients and controls matched for age and sex, had a good inter-observer agreement (κ=0.729) compared to a visual examination (κ=0.467). A cut-off point≥2 discriminate IIH patients from controls, with a sensitivity and specificity of 100%.

TIPIC Syndrome: Beyond the Myth of Carotidynia, a New Distinct Unclassified Entity.

BACKGROUND AND PURPOSE: The differential diagnosis of acute cervical pain includes nonvascular and vascular causes such as carotid dissection, carotid occlusion, or vasculitis. However, some patients present with unclassified vascular and perivascular changes on imaging previously reported as carotidynia. The aim of our study was to improve the description of this as yet unclassified clinico-radiologic entity. MATERIALS AND METHODS: From January 2009 through April 2016, 47 patients from 10 centers presenting with acute neck pain or tenderness and at least 1 cervical image showing unclassified carotid abnormalities were included. We conducted a systematic, retrospective study of their medical charts and diagnostic and follow-up imaging. Two neuroradiologists independently analyzed the blinded image datasets. RESULTS: The median patient age was 48 years. All patients presented with acute neck pain, and 8 presented with transient neurologic symptoms. Imaging showed an eccentric pericarotidian infiltration in all patients. An intimal soft plaque was noted in 16 patients, and a mild luminal narrowing was noted in 16 patients. Interreader reproducibility was excellent. All patients had complete pain resolution within a median of 13 days. At 3-month follow-up, imaging showed complete disappearance of vascular abnormalities in 8 patients, and a marked decrease in all others. CONCLUSIONS: Our study improved the description of an unclassified, clinico-radiologic entity, which could be described by the proposed acronym: TransIent Perivascular Inflammation of the Carotid artery (TIPIC) syndrome.

Facial nerve: from anatomy to pathology.

The facial nerve (CN VII) emerges from the facial nerve nucleus in the pons. It is accompanied by CN VIII along its cisternal pathway, as well as at the internal auditory meatus. Its petrous pathway includes a labyrinthine segment, a horizontal tympanic segment and a vertical mastoid segment until the stylomastoid foramen. It then continues to the parotid gland. Pontine impairment is usually associated with other neurological symptoms. Lesions of the cerebellopontine angle (most often meningioma and schwannoma) initially result in impairment of CN VIII. The impairment of CN VII takes second place. Peripheral impairment (outside of a traumatic context) is most often due to Bell's palsy.

Infectious and metabolic brain imaging.

Central nervous system infectious and metabolic disease is a vast domain. We have chosen to focus particularly on five pathological conditions: brain abscess, herpes encephalitis, Creutzfeldt-Jacob disease, posterior reversible encephalopathy and central pontine myelinolysis. We will pay particular attention to MRI signs and the specific sequences to use in each condition, in addition to the conventional sequences, in order to avoid diagnostic traps. Once the MRI exploration is complete, the diagnosis still cannot be established without knowing the clinical and metabolic context.

[Reversible cerebral vasoconstriction syndrome]. / Le syndrome de vasoconstriction cérébrale réversible.

The reversible cerebral vasoconstriction syndrome (RCVS) is an under-estimated transient acute cerebrovascular disorder. It has long been mistaken as central nervous system vasculitis whereas it is now believed to result from an acute but prolonged vasospasm of cerebral arteries. This disorder can be precipitated by postpartum or vasoactive drug. However, it occurs spontaneously in a significant number of cases. The characteristic clinico-radiological presentation and disease course of the RCVS has been delineated only recently. Mean age at onset is 40-45 years, with a female predominance. A provocative factor can be identified in 12-60% out of the patients. Clinical presentation is predominantly marked by recurrent thunderclap headaches, but can be complicated with focal neurological deficit or seizures. Brain imaging is normal in most cases, but can reveal hemorrhagic or ischemic complications. Cortical subarachnoid hemorrhage is a suggestive finding. A posterior reversible encephalopathy syndrome (PRES) can be seen occasionally. Cerebral angiography reveals multifocal arterial narrowing with string and bead appearance. Cerebrospinal fluid reveals no or mild abnormalities. The disease resumes spontaneously within several days to weeks, whereas vasoconstriction reverses within 1 to 3 months. This clinico-radiological presentation should be promptly recognized in order to avoid unnecessary investigations and aggressive treatment, and lead to search for a triggering factor. Further studies are required in order to clarify the precipitating role of several drugs, and clinical trials are needed to reduce the occurrence of strokes.

Cerebral ischemia complicating intracranial aneurysm: a warning sign of imminent rupture?

BACKGROUND AND PURPOSE: Patients harboring nongiant cerebral aneurysms may rarely present with an ischemic infarct distal to the aneurysm. The aim of this case series was to report clinical and radiologic characteristics of these patients, their management, and outcome. MATERIALS AND METHODS: We undertook a single-center retrospective analysis of consecutive patients admitted during an 8-year period with an acute ischemic stroke revealing an unruptured nongiant (<25 mm) sacciform intracranial aneurysm. Clinical, radiologic, therapeutic, and follow-up data were analyzed. RESULTS: Nine patients were included. The mean size of aneurysms was 9.6 ± 6 mm, and 5 were partially or totally thrombosed. Two patients had a fatal SAH within 3 days after stroke-symptom onset, whereas asymptomatic meningeal bleeding was diagnosed or suspected in 2 others. Most of the patients with unthrombosed aneurysms were successfully treated by endovascular coiling in the acute phase. Thrombosed aneurysms were usually treated with antithrombotics, and most recanalized secondarily, requiring endovascular treatment or surgical obliteration. No recurrence of an ischemic event or SAH was observed during the 31 ± 12 months of follow-up (from 4 to 53 months). CONCLUSIONS: In this single-center series, the frequency of early SAH in patients with ischemic stroke distal to an unruptured intracranial aneurysm was high. Acute management should be undertaken with care regarding antithrombotic use, and early endovascular coiling should be considered.

[Imaging of subarachnoid hemorrhage]. / Imagerie de l'hémorragie sous-arachnoïdienne.

Even if acute subarachnoid hemorrhage (SAH) accounts for only 5% of strokes, its diagnosis is very important because its clinical consequences can be tragic. Recent technological advances in medical imaging have improved diagnostic and therapeutic management of patients with SAH. Nonenhanced CT of the head is the initial imaging modality in suspected SAH for the detection of ruptured intracranial aneurysms. Digital subtraction angiography (DSA) remains the reference exam. Multidetector row CT angiography may potentially replace DSA in the emergency setting, as it provides image data that allows evaluating aneurysmal morphology, the neck size or the visualization of vessels in the vicinity of the aneurysm. For SAH unrelated to aneurysm rupture (15% of cases), MRI and MRA can be added to the diagnostic work-up in order to exclude other differential diagnoses such as venous thrombosis or angiitis. Finally, transcranial color-coded duplex sonography, CT, or MRI are used in clinical practice in order to detect aggravating factors of SAH like hydrocephalus or vasospasm.

Emotional facial palsy following striato-capsular infarction.

Emotional facial palsy (EFP) is a rare condition in which facial paresis is only apparent during reflex movements of the hemiface, such as smiling and laughter. We report the case of a 32-year-old man presenting with EFP as the main symptom of a small striatocapsular infarction. Our case strongly suggests that the anterior arm of the internal capsule is part of the corticonuclear tract that is involved in emotional facial motility.

[Acute anterograde amnesia by infarction of the mamillothalamic tracts]. / Syndrome amnésique aigu par infarctus des faisceaux mamillothalamiques de Vicq d'Azir.

We report a case of persistent anterograde amnesia secondary to an anterior thalamic infarct. A 49-year-old right-handed man is referred for acute anterograde amnesia. Diffusion-weighted imaging performed at 24 hours shows an acute punctiform infarct of the left anterior thalamus, while T2-weighted imaging reveals a contralateral and symmetrical ischemic sequelae in the right anterior thalamus. The two lesions are isolated and remarkably centered with the mamillothalamic tract. We suggest the symptoms are caused by the addition of the two lesions interrupting the mamillothalamic tracts. This is the second clinico-pathological observation of a persistent amnestic syndrome secondary to a bilateral lesion of the mamillothalamic tract.

[Intracranial aneurysms presenting with ischemic stroke]. / Anévrysmes intracrâniens révélés par une ischémie cérébrale.

PURPOSE: To report four cases of patient with an acute ischemic event as a presenting symptom of a berry aneurysm. PATIENTS AND METHODS: One male and three female (aged range 38 to 65 years) patients were admitted for acute stroke. The neuroradiologic finding disclosed aneurysm thrombosis, inferior to twenty five millimetres in three cases. Lumbar puncture was done in one case and showed subarachnoid haemorrage. DISCUSSION: We will discuss the hypothesis leading to the mechanism of aneurysm thrombosis. Two theories will be presented: "hemodynamic" and "parietal" modifications. We will propose a management protocol for these patients with atypical presentation of intracranial aneurysms given the potential risk of rupture. CONCLUSION: The natural history of intracranial aneurysms is still not fully understood. Nevertheless, aneurym thrombosis may occur and lead to ischemic stroke.

[Vertebrovertebral arteriovenous fistula diagnosis and treatment: report of 8 cases and review of the literature]. / Diagnostic et traitement des fistules vertébrovertébrales. Revue de la littérature: à propos de 8 observations.

Vertebrovertebral Arteriovenous Fistula (V.V.A.V.F.) is a relatively rare entity. It may be an incidental finding or be detected in patients presenting with pulsatile tinnitus, cervical bruit, or vertebro-basilar insufficiency. It can be spontaneous but it most frequently is post-traumatic in etiology. The authors report 8 patients, 4 women and 4 men aged between 20 to 77 years, with 4 post-traumatic V.V.A.V.F. and 4 spontaneous V.V.A.V.F. that were seen over a 15 year period. Imaging work-up included Doppler US (n=4), MRI 9n=3) and angiography (n=8). Seven of 8 patients were treated successfully using an endovascular technique (5 with balloon occlusion, 1 with coil embolization and 1 using a mechanical maneuver), without complication or recurrence, except in one case. We compare our results with published reports from the literature and review the underlying pathology and management strategies of V.V.A.V.F.

[Natural history and management of mycotic intracranial aneurysm]. / Anévrysme mycotique cérébral: histoire naturelle et prise en charge thérapeutique.

INTRODUCTION: mycotic intracranial aneurysms are a rare complication of infectious endocarditis. We report four cases of patients with endocarditis, complicated by an acute stroke, revealing a mycotic intracranial aneurysm. PATIENTS AND METHODS: four men (aged range 24 to 63 year old) were admitted for endocarditis, complicated by ischemic stroke in two cases and hemorrhagic stroke in the two other cases, including one with subarachnoid hemorrhage. Neuroimaging disclosed a mycotic cerebral aneurysm in all four cases. DISCUSSION: we will discuss the natural history and the management of mycotic intracranial aneurysm based on a review of the literature and our experience. Three therapeutic options are possible: medical treatment, surgery and endovascular embolisation. CONCLUSION: management of mycotic intracranial aneurysms is still controversial, frequently requiring a multidisciplinary strategy with priority given to endovascular interventions.

[MR-angiography of the head and neck vessels: technical considerations and clinical indications]. / ARM des vaisseaux cervico-encéphaliques: technique, principales applications cliniques.

Magnetic resonance angiography (MRA) is a very valuable tool in the routine evaluation of patients with stroke syndrome. It provides powerful noninvasive imaging of the cervical and intracranial vessels allowing the detection and the diagnosis of vascular anomalies. MRA usefully supplements, during the same examination, the analysis by MRI of the cerebral parenchyma. We will describe the indications of the various techniques (MRA with and without injection of contrast media) and show the value, artifacts and limitations of MRA in atherosclerotic stenosis or occlusive disease and in arterial dissections. This noninvasive vascular assessment will depend on the initial therapeutic orientation. Within the framework of the hemorrhagic stroke, we will discuss the role and the interest of dynamic MR angiography in the tracking and control of intracranial aneurysms and also the contribution of this newer sequences with gadolinium injection in the detection of cerebral vascular malformations.

Ehlers-Danlos syndrome type IV and recurrent carotid-cavernous fistula: review of the literature, endovascular approach, technique and difficulties.

We report the follow-up of a previously published case (Forlodou et al. Neuroradiology 38:595-597, 1996) of carotido-cavernous fistulas (CCFs) in a patient presenting with type IV Ehlers-Danlos syndrome (EDS 4) that were successfully treated twice by an endovascular approach. Initial treatment with a detachable balloon was in 1994 for a right CCF, and, 8 years later, a left CCF was treated by selective transarterial occlusion of the cavernous sinus with coils. Unfortunately, the patient suffered from a spontaneous post-operative intracranial haemorrhage in the left hemisphere and died. Review of the literature, technical considerations for bilateral CCF and complication are discussed.

[Hypertrophic olivary degeneration. MR imaging findings and temporal evolution]. / Degenerescence olivaire hypertrophique. Aspect IRM et évolution temporelle.

PURPOSE: to describe the magnetic resonance imaging features of hypertrophic olivary degeneration (HOD) subsequent to lesion in the "Guillain-Mollaret triangle". MATERIALS AND METHODS: 15 cases of HOD were diagnosed at MR imaging in 12 patients (4 women and 8 men) with posterior fossa lesion. The time interval from the beginning of the disease to the MR examination was 3 weeks to 8 (1/2) years. Evaluation of the changes in signal intensity over time of the lesions was available in 6 patients. RESULTS: Nine cases of HOD were unilateral and three were bilateral. HOD was associated to a lesion of the contralateral dentate nucleus in 8 cases, to a lesion of the ipsilateral central tegmental tract in 5 cases and to a lesion of the contralateral superior cerebellar peduncle in 2 cases. Hyperintensity and hypertrophy of the olive on proton density and T2-weighted images appeared as early as 3 weeks after the ictus. A curved central hyperintensity (CCH) could be observed 7 months after the initial presentation. Decrease in the signal intensity was observed after 3 (1/2) years and abnormal signal intensity could persist for up to 13 years. Palatal myoclonus at 5 months was associated with HOD in one case. CONCLUSION: HOD is considered a trans-synaptic degeneration subsequent to lesions in the Guillain-Mollaret triangle. Hyperintensity and hypertrophy of the olive are observed, sometimes with palatal myoclonus.

[Emergency imaging of cerebrovascular accidents]. / Imagerie des accidents vasculaires cerebraux en urgence.

Over the last 25 years, advances in neuroimaging have significantly changed the evaluation and management of acute stroke syndromes. In the seventies, computed tomography (CT) could differentiate between ischemic and hemorrhagic stroke. Magnetic resonance imaging (MRI) is nowadays the imaging modality of choice in the initial assessment of acute stroke. MRI images can better discriminate acute, subacute and chronic infarcts, differentiate venous from arterial infarcts, detect arterial dissection, stenosis or occlusion. Diffusion-weighted images are highly sensitive and specific to acute infarction and the combination with perfusion technique is suitable to define potentially reversible ischemia (area of cerebral "mismatch" which is thought to represent the so-called ischemic penumbra). This penumbra is a potential therapeutic target of valuable interest for the treating physician.