Progressive moyamoya syndrome associated with de novo formation of the ipsilateral venous and contralateral cavernous malformations: case report

Background: Association of moyamoya disease with multiple vascular malformations is extremely rare. Case Presentation: A 33-year-old man, who had been affected with moyamoya syndrome with TIA during the past 3 years, was admitted to our hospital because of crescendo TIAs with numbness in his right hand and dysarthria. Magnetic resonance angiography showed apparent progression of the steno-occlusive changes bilaterally. We then planned surgical revascularization on the symptomatic side. At the time of readmission for surgery, an asymptomatic small intracerebral hemorrhage in the right frontal cortex was found, which presented on MRI as a CCM. Cerebral angiogram showed avascular lesion corresponding to the location of CCM as well as a newly formed venous malformation on the left side. One month later, STA-MCA anastomosis with pial synangiosis was performed without complications. Significant improvement in CBF on the left hemisphere was confirmed by postoperative single-photon emission CT. There were no ischemic changes on a postoperative MRI, and STA-MCA bypass was apparently patent by MRA. The TIA completely disappeared after surgery, and the patient was discharged without neurologic deficit. Persistence of the CCM and venous malformation were confirmed by T2*-weighted image and 3-dimensional contrast-enhanced gradient echo/SWI 4 months after surgery, respectively. Conclusion: The association of moyamoya syndrome with CCM and venous malformation is extremely rare. The coincidence of the progressive moyamoya syndrome with these newly formed vascular malformations may give a clue to the underlying mechanism of the progression of this rare entity.