dural arteriovenous fistulas ( avfs ) are uncommon , representing only 10% to 15% of all intracranial avfs.5 ) avfs are classified into the following two major groups : congenital and acquired . acquired avfs caused by sinus occlusion , trauma , or iatrogenic injury after craniotomy or ventriculostomy have been reported.7 ) injury to the dural vessels resulting from penetrating head trauma skull fractures , especially in the region crossing the meningeal grooves , has been reported to cause an avf.6 ) here we present the case of a patient with cerebral infarction who experienced a dural avf after craniotomy for superficial temporal artery ( sta ) to middle cerebral artery ( mca ) bypass surgery . a brain magnetic resonance imaging scan revealed multiple acute infarctions in left basal ganglia and frontoparietal lobe , and severe stenosis of the left mca . angiography showed severe focal stenosis of the left m1 and perfusion delay of the mca territory ( figure 1 ) . his condition gradually improved , and follow - up angiography was performed 2 weeks after surgery . selective angiography of the left extracranial artery ( eca ) demonstrated an abnormal vascular channel from the left middle meningeal artery ( mma ) to the middle meningeal vein ( mmv ) just anterior to the border of the craniotomy margin . the screw injured the mma and mmv , and this resulted in the formation of a fistula . although he had no fistula - related symptoms , the abnormal blood flow from the mma influenced the sta - mca bypass flow . therefore , the lesion was occluded with coil embolization ( figure 2 ) . using a guiding catheter in the eca trunk , a microcatheter was navigated into the mma , and then , detachable and pushable coils were inserted into the mma . he was discharged after coil embolization , and he is being followed up in the outpatient clinic . dural avfs represent only 10% to 15% of all intracranial avfs.1 ) although the causes of dural avfs remain uncertain , dural sinus thrombosis and venous thrombosis are important in the pathogenesis of dural avfs.2358 ) another possible cause is iatrogenic injury . several dural avf cases have been reported after burr - hole procedure , ventriculostomy , craniotomy , and craniectomy . pappas et al.6 ) reported recurrent subdural hematomas caused by a dural avf after burr - hole drainage . they performed burr - hole drainage ; however , new acute subdural hematoma occurred at the burr - hole site . angiography revealed a dural avf adjoin the burr - hole made in the previous operative procedure . trauma to the mma , especially in the part of the groove at the internal side of the cranium , can cause a dural avf . inagawa et al.4 ) reported the case of a middle meningeal fistula caused by a head fixation device ( mayfield - kees ) that was used to stabilize the head during surgery for an aneurysm . anatomical studies have shown that two meningeal veins usually accompany the mma and its major branches.6 ) interestingly , the meningeal grooves are mainly occupied by the veins , in compared with the artery . this anatomic connection may elucidate the high frequency of traumatic fistulas , and result in the typical angiography finding of this location , named as " tram tracks".6 ) a tear in the arterial wall from skull fracture can cause a mma fistula.2 ) similarly , iatrogenic injury of the mma can cause a dural avf . in our case , angiography showed that the dural avf originated from the screw tip , and on computed tomography , the screw tip was identified in the middle meningeal groove . this dural avf caused by screw fixation is unique , and it required surgery or endovascular treatment . a dural avf can change the cerebral perfusion and flow dynamics , which can aggravate acute infarction associated with sta - mca anastomosis.7 ) we presented the rare case of a patient with cerebral infarction who experienced a dural avf after craniotomy for sta - mca bypass surgery . when performing craniotomy using screw fixation , it is important to avoid injuring the middle meningeal groove . additionally , surgeons should be careful when fixing bones with screws and plates as fistulas can develop if vessels are injured . we suggest early intracranial embolization for a dural avf after sta - mca anastomosis to prevent further cerebral blood flow compromise .
dural arteriovenous fistulas ( avfs ) are uncommon , representing only 10% to 15% of all intracranial avfs . here 
 we present the case of a patient with cerebral infarction who experienced a dural avf after craniotomy for superficial temporal artery ( sta ) to middle cerebral artery ( mca ) bypass surgery . 
 a 48-year - old man presented with dysarthria and right side hemiparesis . 
 a brain magnetic resonance imaging scan revealed multiple acute infarctions and severe stenosis of the left mca . 
 therefore , sta - mca bypass surgery was performed . a follow - up angiography performed 2 weeks after the surgery showed an abnormal vascular channel from the left middle meningeal artery ( mma ) to the middle meningeal vein ( mmv ) just anterior to the border of the craniotomy margin . 
 this fistula originated from a screw used for cranial fixation . 
 the screw injured the mma and mmv , and this resulted in the formation of a fistula . 
 the fistula was successfully treated with transarterial embolization . 
 surgeons should be careful when fixing bones with screws and plates as fistulas can develop if vessels are injured .