[Imaging of acute cerebellitis in children. Report of 4 cases]. / Imagerie des cérébellites aiguës chez l'enfant. A propos de 4 observations.

Acute cerebellitis is one of the main causes of acute cerebellar dysfunction in children. It is either infectious, usually viral, post-infectious or post vaccinal in etiology. Diagnosing acute cerebellitis may be difficult in patients with only subtle cerebellar signs and when cerebro-spinal fluid examination is normal. MRI is the most adequate imaging technique to demonstrate cerebellar involvement. The authors report the clinical and neuro-imaging findings in 4 paediatric cases. Patient's age varied from 2 to 7 years and predominant clinical symptoms were fever, headache and vomiting; ataxia was noted only in 2 cases. Viral serologic tests were negative in 3 cases and demonstrated Epstein-Barr virus in 1. Initial MRI examination (2 cases) demonstrated increased intensity on T2W and Flair sequences of the cerebellar gray matter with pial enhancement. Clinical outcome was good with complete resolution of symptoms in 3 cases and persistent mild right upper limb paresis in one. The resolution of the signal abnormality was well demonstrated on MRI in one case, suggesting an inflammatory etiology with moderate residual cerebellar atrophy.

[Discoid menisci in children: ultrasonographic features]. / Le ménisque discoïde chez l'enfant: aspects échographiques.

OBJECTIVE: Discoid meniscus is a rare congenital pathology affecting mainly the lateral meniscus. Radiological diagnosis, initially based on arthrographic findings, is now established on well defined MRI criteria. In this study, ultrasonography (US) was the modality proposed for diagnosing discoid meniscus and compared to the normal sonographic meniscal pattern. Subjects and methods. 8 children aged from 6 to 11 years, with a symptomatology highly suggestive of meniscal pathology, were investigated by US of both knees, followed by MRI in 3 and arthroscopy in all cases. RESULTS: In all 8 cases, a meniscus was diagnosed as discoid when it no longer had its normal triangular shape, was abnormally elongated and thick and demonstrated a heterogeneous central pattern. Associated lesions (fracture, cystic degeneration) were well demonstrated on US. The lateral meniscus was involved in all 8 cases, the pathology was bilateral in 5 cases and MRI/US correlation was good in 3 cases. Arthroscopy confirmed US findings in all cases. CONCLUSION: US, a more widely available imaging modality, is a reliable technique for the diagnosis of discoid meniscus in children.

[Atypic radiologic aspect of a renal cell carcinoma in children]. / Présentation radiologique atypique d'un carcinome à cellules claires du rein chez l'enfant.

Renal cell carcinoma is rare in children and is usually found in late childhood. The authors report on an exceptional case of renal cell carcinoma in a 10-year-old girl. The radiological aspect is misleading and has not been previously reported in the literature. Renal cortex was thin because of congenital megalo-ureter, so the tumor developed entirely into excretory cavities (to the proximal ureter), while a primitive urothelial disease (tumoral or inflammatory) was first evoked. The atrophied cortex was the tumoral starting point which prolapsed into excretory cavities, upraising the urothelial epithelium.

[MRI findings in the diagnosis of pseudotumoral humeral hydatid]. / Apport de l'IRM dans le diagnostic d'une hydatidose humérale pseudo-tumorale.

Hydatidosis of bone is rare. Vertebral localizations predominate. Standard imaging may be misleading, suggestive of a malignant tumor or infection. We present the case of a patient with a humeral hydatid. This localization is very rare and presents an unusual radiographic aspect. Computed tomography produces an image suggestive of a tumor. The correct diagnosis can be established with MRI, particularly with the STIR sequence. In our patient, MRI enabled us to establish the diagnosis preoperatively and evaluate extension. MRI has been found to be highly contributive to the diagnosis of hydatidosis of bone and for assessment of intra- and peri-osseous extension.

[Hydatid cyst of soft tissues: MR imaging findings (Report of three cases)]. / Kyste hydatique des tissus mous: apport de l'IRM (A propos de trois observations).

Three cases of hydatid disease of the soft tissues are reported. All presented as soft tissue lesions in the neck and lower extremities. All three cases were studied with ultrasound (US) and magnetic resonance (MR) imaging techniques. Two patients presented with multivesicular lesions, which were considered diagnostic for hydatid disease. The third showed a lesion with hypoechoic solid and lobulated pattern mimicking lymph node. MR outlined the cystic pattern with intense peripheral enhancement and was suggestive of an infected cystic lesion. Surgery was performed in all three cases. Hydatid disease presenting in the soft tissues can be diagnosed with confidence, when US and/or MR shows multivesicular lesions. MR appears to be the most useful imaging technique when a complex or solid pattern is present. Enhancement of the peri-cystic soft tissues can be considered as a suggestive MR feature of soft tissue hydatid disease.

Normal galenic drainage of the deep cerebral venous system in two cases of vein of Galen aneurysmal malformation.

INTRODUCTION: Vein of Galen aneurysmal malformations (VGAM) are assumed to be related to the persistence of the embryonic median prosencephalic vein of Markowski, which does not involute in cases of VGAM and becomes the venous collector of the shunt, characteristic of the malformation. The arterial feeders of VGAMs are all primitive meningeal arteries present during the embryonic period of the constitution of the malformation. It has also been assumed that the internal cerebral veins were absent in patients presenting with VGAM. There is no clear evidence indicating, however, that the deep venous structures cannot develop normally. CASE REPORTS: We report on two cases of VGAM in which superselective retrograde transvenous catheterization and MRI demonstrated that normal internal cerebral veins were draining into the aneurysmal vein of Galen. CONCLUSIONS: It is conceivable that, as in our patients, this drainage pattern is only angiographically detectable via selective retrograde transvenous drainage. The possibility of such normal deep galenic venous drainage must be considered in VGAM management, as it may imply occurrence of adverse effects when the malformation is occluded on the venous side.