[Intraosseous arteriovenous malformations]. / Les malformations artérioveineuses intra-osseuses.

Intraosseous arteriovenous maxillomandibular malformations are rare. The diagnosis is primarily clinical (children with pulsatile osseous tumefaction, bleeding at cingulum), completed with imaging techniques (TDM and/or MRI). Arteriography is indicated only at the time of therapeutic management. The evolution may vary greatly (four levels: quiescence, expansion, destruction, decompensation) and usually evolves because of hormonal changes or trauma. Radiotherapy and vascular ligatures are no longer recommended. The best treatment is direct or transarterial embolization. Surgical resection, when feasible, must be thorough. It is indicated in case of failure or recurrence after embolization.

[Head and neck superficial venous malformations]. / Malformations veineuses superficielles cervico-faciales. Mise au point.

Management of vascular malformations and vascular tumors has recently been maximized by the establishment of an accurate clinical and histological classification and by the development of multidisciplinary expert consultations. Head and neck localizations of venous malformations are common, thus maxillo-facial surgeons should be aware of the characteristics of this pathology and the principles of its management. Diagnosis is mainly clinical and must be certified by Doppler-ultrasonography and contrast enhanced magnetic resonance imaging with T2 fat-saturation sequence. Therapeutic decision depends on the volume of the lesion, and on functional, cosmetic and psychological complaints. Sclerotherapy is now the preferred treatment of head and neck venous malformations. It is performed in specialized interventional radiology units by intralesional injections of sclerosing solution under fluoroscopic guidance. Surgery is useful in some cases, either on its own or following sclerotherapy. In case of bulky lesion, it is necessary to search for and prevent a severe coagulopathy before planning any intervention.

[Deep vein thrombosis revealing myeloproliferative syndrome in two adolescents]. / Thrombose splanchnique révélatrice d'un syndrome myéloprolifératif chez deux adolescentes.

Deep vein thrombosis occurs in 30% of patients with essential thrombocythemia, but rarely at initial diagnosis. We report two pediatric patients with essential thrombocythemia revealed by atypical deep vein thrombosis. First, a 16-year-old girl presented Budd-Chiari syndrome revealed by a hemorrhagic shock. Clinical exam revealed isolated splenomegaly. A search for thrombophilia found a factor V Leiden homozygous mutation and a Jak2 mutation. Bone marrow biopsy confirmed the diagnosis of a myeloproliferative disorder. The second case, a 17-year-old girl, had a routine examination by her physician that revealed splenomegaly. Ultrasonography displayed thrombus in the splenic and portal vein. An isolated Jak2 mutation was found and a myeloproliferative disorder was confirmed by bone marrow biopsy. The diagnosis of myeloproliferative disorder was made in both patients presenting atypical venous thrombosis with a Jak2 mutation and confirmed by bone marrow biopsy. These initial presentations of myeloproliferative disorders are rare in childhood and possibly underdiagnosed.