[Symptomatic aneurysms of the postero-inferior cerebellar artery. A multicenter retrospective study of 29 cases]. / Anévrysmes symptomatiques de l'artère cérébelleuse postéro-inférieure. Etude rétrospective multicentrique de 29 cas.

A multicenter retrospective study of 29 cases of posterior inferior cerebellar artery is reported. Over a period of 21 years, the frequency of posterior inferior cerebellar artery aneurysm among all intracranial aneurysm was estimated to 1.38 p. 100 of cases of aneurysms followed by 3 University Hospitals. Frequency of rupture appeared to be very high (93 p. 100) in this series probably because of the type of selection. Average grade of presentation according to Hunt and Hess classification being < III in 3 fourth of the cases. Neither clinical presentation nor suspicious etiological factors were specific of this localization. Only two cases were of pseudotumoral appearance. Positive diagnosis of subarachnoid hemorrhage was made by CT scan. Angiograms gave diagnosis of localization of the malformation and its type. Intraventricular hemorrhage was found in 62 p. 100 of our cases: all had hemorrhage of the fourth ventricle. Hydrocephaly was more frequent as compared to supratentorial localizations, Vasospasm was less frequent as in supratentorial localizations. Nimodipin seems to be efficient. Therapeutic possibilities are primary dominated by surgery with good results when it is possible. Endovascular treatment is under evaluation.

[Proximal aneurysms of the postero-inferior cerebellar artery. Therapeutic consideration upon a multicenter retrospective study of 24 cases]. / Anévrismes proximaux de l'artère cérébelleuse postéro-inférieure (PICA). Considération thérapeutique au vu d'une série rétrospective multi-centrique de 24 cas.

Aneurysms of the postero inferior cerebellar artery (PICA) are relatively rare as it accounts for only 0.5% to 3% of all intracranial aneurysms, even though this localization is in second place for frequency in the posterior fossa, after aneurysms of the basilar artery. Among them, origin from the anterior or latero-medullary segment of PICA would account for 80% of cases. In this retrospective multicenter study, we report 24 cases of PICA aneurysms with their clinical and anatomic features as well as either their surgical or endovascular treatment. We also carried out an exhaustive review of the literature in order to propose the typical clinical features of this type of lesion. Of particular significance: a predominance of female patients of approximately 50 years of age ; posterior direction; constancy of hemorrhage in the fourth ventricle in case of ventricular involvement of subarachnoid hemorrhage. The various therapeutic possibilities are discussed and their results are analyzed. The prognosis for PICA aneurysms would seem to be favorable, depending, of course, on initial clinical grade.

Crowned dens syndrome: a manifestation of hydroxy-apatite rheumatism.

Crowned dens syndrome is defined as an association of acute cervical pain and calcifications in the peri-odontoid space. The authors report one case of this rare localization of hydroxy-apatite rheumatism and review 12 similar cases in the literature. This disease affects only adult females. Patients present with inflammatory signs, can be treated with non-steroid anti-inflammatory drugs and recover without sequela. Calcium pyrophosphate dihydrate deposition can also lead to this syndrome. Other perioodontoid calcifications and ossifications, usually asymptomatic, appear only as a radiologically crowned dens.

[Screwing the odontoid process. A functional operation]. / Le vissage de l'odontoïde. Une intervention fonctionnelle.

The authors describe a case of direct screw fixation of the odontoid process via an anterolateral retropharyngeal subhyoid pre-sternomastoid approach and discuss the indications for this operation. In this particular case, immobilization by a cervical collar or a halo vest was not chosen because of its constraining character and the risk of secondary displacement and pseudarthrosis. C1-C2 or occipitospinal arthrodesis, whether performed via a posterior, lateral or anterior approach, is difficult to perform and always leads to a functional handicap. The transoral approach does not allow direct screw fixation of the dens. Dens screwing via an anterior pre-sternomastoid subhyoid approach is the most logical and least disabling technique. The subhyoid approach is much simpler than the suprahyoid approach. This technique is used in fractures of the odontoid process with an ablique downward and backward fracture line, with or without arch fracture of C1, and allows screwing perpendicular to the fracture line. Considering the present results and the literature, the double screw fixation does not seem to be justified.

[Cerebral immunoblastic lymphoma and the acquired immunodeficiency syndrome]. / Lymphome immunoblastique cérébral et syndrome d'immunodéficit acquis.

A case of acquired immune deficiency syndrome (AIDS) is reported in a young homosexual Venezuelan male. It is of special interest to note the association of cytomegalovirus polyvisceral infection, frequent during AIDS, and a brain immunoblastic lymphoma, an infrequent tumour in that pathology.