3 Tesla serial magnetic resonance imaging of human African trypanosomiasis (Trypanosoma brucei gambiense) and review of the literature.

We report serial magnetic resonance imaging (MRI) findings and follow-up in a case of human African trypanosomiasis (HAT) presenting with limited lesions followed by early and complete resolution. We searched the literature for documented cases and reviewed MRI findings before treatment. A 30-year-old Lebanese man, who had lived in Gabon for six years, presented with a two-year history of rash, anorexia, weight loss, arthralgia, paresthesia, and hypersomnia. Previously, the patient had received corticosteroid therapy for unconfirmed ANCA-associated vasculitis. Physical examination revealed a painless chancre on the left arm located at the site of an old insect bite, enlarged cervical, axillar and inguinal lymph nodes, hepatosplenomegaly and impaired concentration. Blood analysis showed an elevated protein level (90g/L) with hypoalbuminemia (24.2g/L) and elevated IgM (26.4g/L). Bone marrow aspirate and biopsy failed to detect any parasite. Polymerase chain reaction tests on blood and cerebrospinal fluid were positive for Trypanosoma. Serology tests confirmed the diagnosis of HAT due to Trypanosoma brucei gambiense infection. 3T MRI showed lesions in the hypothalamus and basal ganglia, the internal capsule, and the mesencephalon bilaterally. Follow-up MRI showed interval progression of the abnormalities. Treatment with melarsoprol was followed by clinical improvement with regression of the lesions on the three-month MRI, then total resolution at the 10-month follow-up. This case highlights a pattern of mild MRI lesions in T. brucei gambiense HAT with a total and rapid resolution under treatment. The literature review (16 HAT cases with sufficient radiological data, included ours) revealed an MRI pattern of brain lesion distribution that could be helpful for diagnosis and orienting biological tests.

Late onset hereditary episodic ataxia.

OBJECTIVE: Episodic ataxias (EA) are hereditary paroxysmal neurological diseases with considerable clinical and genetic heterogeneity. So far seven loci have been reported and four different genes have been identified. Analysis of additional sporadic or familial cases is needed to better delineate the clinical and genetic spectrum of EA. METHODS: A two generation French family with late onset episodic ataxia was examined. All consenting family members had a brain MRI with volumetric analysis of the cerebellum. Haplotype analysis was performed for the EA2 locus (19p13), the EA5 locus (2q22), the EA6 locus (5p13) and the EA7 locus (19q13). Mutation screening was performed for all exons of CACNA1A (EA2), EAAT1 (EA6) and the coding sequence of KCNA1 (EA1). RESULTS: Four family members had episodic ataxia with onset between 48 and 56 years of age but with heterogeneity in the severity and duration of symptoms. The two most severely affected had daily attacks of EA with a slowly progressive and disabling permanent cerebellar ataxia and a poor response to acetazolamide. Brain MRI showed in three affected members a decrease in the ratio of cerebellar volume:total intracranial volume, indicating cerebellar atrophy. No deleterious mutation was found in CACNA1A, SCA6, EAAT1 or KCNA1. In addition, the EA5 locus was excluded. CONCLUSIONS: A new phenotype of episodic ataxia has been described, characterised clinically by a late onset and progressive permanent cerebellar signs, and genetically by exclusion of the genes so far identified in EA.

Hemorrhagic presentation of frontal partially calcified pilocytic astrocytoma in an 18-year-old woman: A case report and literature review as "clinical case".

We report an unusual case of a frontal partially calcified pilocytic astrocytoma (PA) (WHO grade 1) in an 18-year-old woman who presented with acute, spontaneous intracerebral hemorrhage. Histopathology revealed the PA was mixed with psammoma bodies and areas of vascular proliferation responsible for a hypervascular pattern. The patient underwent a total gross resection. MRI showed no residual tumor at the 18-month follow-up and her neurological deficits improved after rehabilitation. Only 20 cases, including ours, of hemorrhagic presentation of PA in adults have been reported to date with enough radiological data. Furthermore, hemorrhagic presentation of a calcified PA is extremely rare. To date only two other cases of calcified PA with hemorrhagic presentation have been reported, one in an adult and one in an infant as described by Shibao et al. (2012) and Kapoor et al. (2015) respectively. Endothelial proliferation may be the main cause of bleeding in these lesions. In our case, a hypervascular pattern was exhibited by histopathological findings. A diagnosis of PA should be considered, especially when calcifications are present within a hemorrhagic tumor lesion.

[CT and MRI features of arachnoid cyst of the petrous apex: report of 3 cases]. / Aspects TDM et IRM du kyste arachnoïdien de l'apex pétreux.

PURPOSE: To describe the CT and MRI features of 3 cases of arachnoid cyst of the petrous apex. PATIENTS AND METHODS: Three patients with isolated trigeminal neuralgia, trigeminal hypoesthesia, and sinusitis. Axial and coronal CT images were obtained. T1W, FSE T2W, FLAIR, T2*W and diffusion-weighted MR sequences were obtained. RESULTS: In all cases, both CT and MRI showed expansile lesions eroding the petrous apex. Lesions were hypodense on CT and isointense to CSF on MRI, without contrast enhancement. In one case, the lesion was contiguous with Meckel's cave with temporal fossa and sphenoid sinus extension. CT and MR imaging features are useful to distinguish arachnoid cysts of the petrous apex from other benign lesions of the petrous apex. CONCLUSION: CT and MRI imaging features allow diagnosis of arachnoid cyst of the petrous apex because its imaging features, especially on DWI, are different from other cystic lesions of the petrous apex, namely cholesteatoma. It should be considered in patients with trigeminal involvement, especially trigeminal neuralgia.

Cerebral developmental venous anomalies associated with head and neck venous malformations.

PURPOSE: To study cerebral developmental venous anomalies in patients with extensive venous malformations of the head and neck. METHODS: All patients had undergone carotid angiography 10 to 15 years previously. Four-vessel cerebral angiography was carried out in 40 patients with venous malformations. All patients had a physical examination, 16 had CT, and 22 were examined with MR imaging. One patient had MR angiography. RESULTS: Eighteen developmental venous anomalies were noted in 8 (20%) of 40 patients. Four patients had multiple anomalies, and these were bilateral in 1 patient. Developmental venous anomalies seen in association with cervicofacial, cutaneous, and mucosal venous malformations were remarkable in their absence of neurologic events and associated cavernoma; significance of ectatic venous convergence, extension, and preponderance of deep drainage routes; and frequency with which they multiple in occurrence. CONCLUSION: Developmental venous anomalies have a remarkable prevalence of 20% in patients with extensive superficial venous malformations. Therefore, it is important to search for a cerebral developmental venous anomaly when confronted with a cervicofacial venous malformation.

MR manifestations of subependymomas.

PURPOSE: To provide a description of the MR and enhanced MR appearances of subependymomas. METHODS: We reviewed the MR examinations of eight cases of pathologically proved subependymomas and correlated them with operative and pathologic reports, and also reviewed the previous published cases of subependymomas documented by MR. Gadopentetate dimeglumine-enhanced MR examination was performed in seven cases. RESULTS: One patient presented with four subependymomas, two patients had subependymomas of the cervical spine, and the others were intraventricular with no transependymal extension. They were isointense to hypointense relative to normal white matter on T1-weighted images, heterogeneous in five cases. Minimal (n = 1) or no (n = 3) enhancement was noted in four cases, and moderate or marked enhancement was noted in three cases. CONCLUSION: We conclude that even though there is no specific sign of subependymomas, when confronted with a complete intraventricular lesion or with a spinal lesion causing little or no edema which is minimally enhancing or nonenhancing, one must consider the diagnosis of subependymoma.

Internal carotid artery dissection causes hypoglossal nerve palsy: CT, MRI, and angiographic findings.

A case of unilateral XIIth nerve palsy due to the dissection of the internal carotid artery is reported. The clinical and radiological features are described. In this patient, cranial nerve palsy is probably the result of compression by an enlarging carotid artery due to mural hematoma. Diagnosis is discussed with emphasis on magnetic resonance imaging findings. Magnetic resonance imaging is also useful for follow-up of arterial lesions.

[Postvaccinal encephalitis in adult. A case with anatomo-clinical report (author's transl)]. / Encéphalite post-vaccinale de l'adulte, Etude anatomo-clinique d'une observation.

While post-vaccinal encephalitis in children is unfortunately well known, its occurrence in adults is rather exceptional. The calendar of a poly vaccination situated so close to each other, most probably account for such an evolution. The case reported concerns a man of 27 years who presented 10 days after a polyvaccination (7 vaccines in 2 months) altered consciousness, epileptic fits, right hemiplegia, vegetative dysfunctions and meningeal status. Evolutionary clinical course led to death in 21 days. Neuropathological findings showed lymphocytic infiltrates in the cortex and basal ganglia, congestive aspect with petechial areas in the white matter and inflammatory meningeal infiltrates. All viral investigations both in the blood, brain and cerebrospinal fluid remained negative. Post-vaccinal encephalitis is reviewed. Vaccination cannot be condemned, but in case of polyvaccination lapse of time in between vaccines should be longer so as to prevent such exceptional evolution and fatal course.

[Emergency disobliteration of the carotid prepolygonal segment. Personal experience of 76 cases]. / La désobstruction d'urgence de l'axe carotidien dans son segment pré-polygonal. Expérience personnelle à partir de 76 observations.

The authors report 76 cases of carotid obstruction, mainly localized at the origin of the carotid artery, that have been operated upon in emergency. Two types of lesions are considered: occlusion and very tight stenosis. The principle of early surgery in cases of acute occlusion is very controverse. According to the facts reported (38 cases) results are rewarding when operative decision is taken under precise conditions judged as favorable: short lapse of time since occlusive onset, absence of intracranial hypertension, absence of comatose state and no sign of brain oedema. Some patients under go surgery in the priviledged condition of being already in a medico-surgical unit (post operative, post angiographic, embolic occlusions). Majority present the most common hemiplegic attack. However difficulty resides in the inefficient mode of transport to hospital and lack of highly specialized units on admission. A very tight stenosis (at extreme a pseudo-occlusive stenosis) with clinical recurrent deficit, modified Loppler's recording and hemodynamic repercussion at angiography is an operative emergency. When results of early surgery on 38 cases of stenosis are compared to those of late operation in 14 similar cases early decision becomes compulsory once tight stenosis of the carotid artery is identified and operative criteria respected. In the light of this report that "wait and see attitude" needs be somewhat revised when confronted to the dramatic ictal hemiplegia.

[Occlusion of the vertebral artery (100 personal cases)]. / Occlusion de l'artère vertébrale (100 cas personnels).

Occlusion of the vertebral artery is usually due to atherosclerosis. According to the site and extension of the arterial lesions 3 clinico-pathologico-angiographic situations can be encountered: segmental occlusion (proximal: V1 or distal: V3, V4), multisegmental (mainly V1-V2, sometimes V1-V2-V3) or extensive (V1 or V4). Subsequent infarctions are localized in ipsilateral cerebellar lobes and ipsilateral lateral part of the medulla oblongata; supra-medullary involvement is rare and indicates a propagation of the vertebral thrombus into the basilar artery. Cerebellar, vestibular or cerebello-vestibular strokes and Wallenberg's syndrome are the more frequent clinical disorders. They are often preceded by occipito-cervical headache. Contrary to a common belief, the vital risk in vertebral artery occlusion is not negligible. Among 160 cases, 100 of which are personal, mortality was 25%. In fact benign segmental and proximal occlusion adequately compensated, specially when isolated, must be opposed to segmental distal occlusion and extensive occlusion. Angiography and Döppler examinations localize arterial lesions and subsequent hemodynamic disorders. The treatment is often symptomatic only. Surgery of the proximal vertebral artery may in some cases be the only hope of preventing occlusion.

[Occlusion of the basilar artery. A review with 17 personal cases (author's transl)]. / Occlusion du tronc basilaire.

Occlusion of the basilar artery is mainly of atherosclerotic origin; embolic occlusion, dissecting aneurysm, trauma and arteritis are less frequent. Pathologic and angiographic findings allow to classify basilar artery occlusions in three types: segmental (superior, medial or inferior), plurisegmental and extensive. The infarcted areas involve brain stem, especially pons and cerebellum, also diencephalon and cerebral hemispheres, in various combinations. Clinically, there is typically a prodromic stage, with transient ischemic attacks (vertigo, headaches, visual disturbances, motor deficit). Few weeks later, a decreased level of consciousness and motor anomalies are the most important signs. A fatal outcome is noted in 85,98 p. 100. Among laboratory examinations, only angiography proves the occlusion: it also shows the arterial supply (carotido-basilar reflux; inter-cerebellar anastomosis). Computed tomography usually eliminates an expanding mass of the posterior fossa. Management is only of general type. Surgical management of carotid arteries stenosis may ameliorate the anastomotic flow.

[Intramedullary epidermoid cyst. Contribution of magnetic resonance imaging]. / Kyste épidermoïde intra médullaire. Apport de l'imagerie par résonance magnétique.

Epidermoid tumors are seldom found as a cause of spinal cord compression; still fewer involve the spinal cord itself. We report a case of a thoracic intramedullary epidermoid tumor documented by MRI.

[Spontaneous hematomas of the cerebellum. 28 personal cases]. / Hématomes spontanés du cervelet. Vingt-huit observations personnelles.

Cerebellar hematomas constitute an emergency as emphasized by a study of 28 personal and 189 published cases. Accounting for 10 per cent of the total of cerebral hemorrhages, they occur mainly in patients after 40 years of age essentially as a complication of hypertension. An evocative stereotyped triad characterizes their sudden onset: severe headache, repeated vomiting, vertigo and imbalance. In their subacute and acute forms, a rapid impairment of consciousness occurs. Death is constant in such cases. Computerized axial tomography is the essential mean of accurate diagnosis and shows the subsequent consequences on other brain structures. Surgical evacuation of hematomas preceded or not by ventricular drainage is the useful procedure in most cases. Results depend on a timely decision and on the conscious level. In other cases, the spontaneous course is more favorable. Brain herniation is however possible and the presence of a vascular posterior fossa malformation must be kept in mind.

MRI evaluation of sacral cysts.

Sacral cysts or intrasacral sacral meningeal cysts constitute a well-defined entity. Their clinical presentation is protean. Few cases have been reported concerning their MR aspects. From a series of six patients, the authors present the MR images. MRI is the examination of choice to demonstrate their liquid content. MRI provides a good evaluation of the lesion, and sagittal images show the intrasacral development. MRI scan appears to be superior to CT scan.

Thoracic disc herniation and spinal cord compression. MRI and gadolinium-enhancement.

The authors present a study of 6 patients aimed at assessing the role of Magnetic Resonance Imaging with gadolinium-enhancement in the diagnosis of thoracic disc herniation. The results of MRI were compared with the findings of computed tomography, myelography and surgery. In two patients, the signal from the herniated disc was so low on all sequences that thoracic disc herniation was diagnosed only on the mass effect on the cord. The anterior longitudinal epidural venous plexus (AEVP) is displaced posteriorly and thickened in case of thoracic disc herniation. Gadolinium-enhancement of AEVP was marked in these conditions, giving a "tent-like" round configuration, or "lifted band" appearance. The exact volume and mass effect of the thoracic disc herniation were assessed by T1-enhanced images on the sagittal and axial planes.

[Facial diplegia in the course of childhood Lyme disease: bilateral enhancement of the facial nerve and MRI after injection of gadolinium]. / Diplégie faciale au cours d'une maladie de Lyme de l'enfant: rehaussement bilatéral du nerf facial et IRM après injection de Gadolinium.

We report a rare case of Lyme disease presenting as a bilateral seventh cranial nerve palsy and meningitis. The MR appearance was an enhancement of the internal auditory canal segment and mastoid segment of the seventh cranial nerve, in the absence of parenchymal lesions. One should consider Lyme disease in the differential diagnosis of bilateral seventh cranial nerve palsy with enhancement.