Variations in the branching patterns of the anterior choroidal artery: an angiographic study with special reference to temporal lobe epilepsy surgery.

BACKGROUND: The preservation of the anterior choroidal artery (AChA) is essential for avoiding neurological sequelae after mesial temporal lobe epilepsy (mTLE) surgery. The purpose of this study is to reveal the anatomical variation in which the perforating branches arise from the plexal segment of the AChA by using a modern neuroimaging modality. METHODS: This study analyzed 3D rotational angiography (3DRA) images from 56 subjects. The AChA and perforating branches were visualized using slab MIP. We analyzed branching patterns, courses of the perforating arteries arising from the plexal segment of the AChA, and the anastomosis of the AChA with other cerebral arteries. RESULTS: The slab MIP applied to 3DRA visualized one or more perforating branches from the AChA in 92.9% of cases. The presence of perforating branches arising from the AChA plexal segment was 17.3%. Most of the branching points of plexal perforators were likely located in the operative field during hippocampal resection. The course of the AChA plexal perforators included the posterior limb of the internal capsule. Anastomosis with other cerebral arteries was visualized in 25% of the AChA with plexal perforators. CONCLUSIONS: 3DRA slab MIP was useful for visualizing the perforating branches of the AChA. Our results showed the possibility that surgical manipulation of the choroid plexus may cause infarction in the AChA territory. We suggest that the existence of the AChA plexal perforators should be recognized to further enhance the safety of hippocampal resection for mTLE.

Usefulness of 3D DSA-MR fusion imaging in the pretreatment evaluation of brain arteriovenous malformations.

RATIONALE AND OBJECTIVES: For the evaluation of patients scheduled for the treatment of brain arteriovenous malformations (AVMs), accurate anatomical information is essential. The purpose of this study was to assess the usefulness of three-dimensional (3D) digital subtraction angiography (DSA)-magnetic resonance (MR) fusion imaging for the pretreatment evaluation of AVMs. MATERIALS AND METHODS: The study population consisted of 11 consecutive patients (7 males, 4 females; age 10-72 years; mean 45 years) with brain AVMs. All prospectively underwent pretreatment MR imaging (MRI), MR angiography (MRA), and two-dimensional (2D) and 3D DSA. The 3D DSA and MR images were semiautomatically fused with fusion software on a workstation. In the delineation of AVM nidus, feeder, drainer, and relationship between AVM and the adjacent brain structures, two radiologists independently evaluated MRA and MRI, three-dimensional (3D) DSA, and MRI, and 3D DSA-MR fusion images using a 4-point scoring system. The referring neurosurgeons were asked whether the information provided by 3D DSA-MR fusion images was helpful for treatment decisions. RESULTS: For all four items, the delineation was significantly better with the 3D DSA/MRI or 3D DSA-MR fusion images than the MRA/MRI images. Although the delineation for the nidus, feeder, and drainer were not significantly different between the 3D DSA/MRI and 3D DSA-MR fusion images, 3D DSA-MR fusion imaging were significantly better for the relationship between AVM and the adjacent brain structures than 3D DSA/MR imaging (P = .0047). The information provided by 3D DSA-MR fusion images was helpful for treatment decisions in all cases. CONCLUSION: 3D DSA-MR fusion images are useful for the pretreatment evaluation of brain AVMs.