Matas test revisited: carotid compression for embolization of high-flow pediatric pial arteriovenous fistulas

OBJECTIVECerebral pial arteriovenous fistula (AVF) is a rare vascular malformation and may cause hemorrhage and neurological deficit. The presence of high-flow shunts constitutes a challenge when performing the endovascular technique, due to risk of distal embolization. The authors report a simple maneuver, adapted from the Matas test, that was successfully applied to treat a child with two pial AVFs.METHODSAn 8-year-old boy presented with headache and vomiting due to two single-channel high-flow intracerebral pial AVFs. He was treated with an endovascular approach using brief, gentle compression of the ipsilateral cervical carotid artery. The temporary flow arrest ensured proper placement of the first coil, allowing definitive obliteration of the shunt.RESULTSThere were no complications with the procedure, and the patient recovered uneventfully. Throughout the 9-month follow-up, the patient experienced a stable neurological condition, with both fistulas occluded and improvement of local circulation.CONCLUSIONSThis easy-to-perform maneuver allows precise positioning of embolic material into high-flow shunts to facilitate treatment of pial AVF.

Giant Multilocular Fusiform Aneurysm of the Posterior Cerebral Artery

A 60-year-old woman presented with a giant posterior cerebral artery aneurysm. Her visual field examination revealed right upper quadrantanopia. Because of the difficulty of the neck clipping, we performed parent artery occlusion using the Guglielmi detachable coils following balloon Matas test monitored with single photon emission computed tomography (SPECT) with 99mTc-d, l hexamethyl-propylene-amine oxime. Postoperative left internal angiography showed the left occipital region was supplied by a leptomenigeal collateral via left the middle cerebral artery. Six months after embolisation the aneurysm was completely thrombosed on MR imaging. Her visual field deficits had also improved six months after embolisation. A combination of the balloon Matas test with SPECT followed by parent artery occlusion is an excellent method to treat such giant aneurysms.

Evaluation of Brain Collateral Circulation by the Transcranial Color Doppler—Guided Matas' Test

For the determination of the indication for reconstruction of the carotid artery in patients with head and neck cancer, a color Doppler—guided Matas' test was performed to examine brain collateral circulation and blood flow of the middle cerebral artery (MCA) and internal carotid artery (ICA). Both SSA-270A convex (3.75 MHz) and linear (3.75 MHz and 2.5 MHz) array probes (Toshiba Co, Ltd) were used for this investigation. A temporary occlusion test (60 seconds) by digital pressure on the common carotid artery was performed on 30 patients with head and neck cancer. The results were classified into four groups according to the relative flow volume (percent blood flow volume before the test) of the MCA: group A, with a flow volume of 87% or more; group B, with a flow volume between 72% and 86%; group C, with a flow volume between 57% and 71%; and group D, with a flow volume of 56% or less. The relative flow volume of the MCA was correlated with the ICA stump pressure and single photon emission computed tomography during a balloon Matas' test (ICA occlusion). This test seems to be useful in predicting the risk of carotid resection without reconstruction and in determining the indication for reconstruction of the carotid artery.