John C. Chaloupka

Evolving experience with direct puncture therapeutic embolization for adjunctive and palliative management of head and neck hypervascular neoplasms.

Objectives: The use of percutaneous, direct puncture therapeutic embolization (DPTE) of hypervascular head and neck neoplasms is a relatively new modality that may be used to supplement or supplant conventional endovascular transarterial embolization. Although the preliminary clinical experience reported by a single group has been favorable, extensive case series experience is lacking. This prompted us to review our recent clinical experience with these techniques to determine safety, efficacy, and emerging role in the overall neurointerventional therapeutic armamentarium.

Tertiary microvascular territories define lacunar infarcts in the basal ganglia

Lacunar infarcts are commonly found in the basal ganglia, though little is known about the organization of small‐scale microvascular territories that presumably subtend lacunae. We investigated microvascular territories of the lenticulostriate arteries, the recurrent artery of Heubner, the anterior choroidal artery, and striate branches of the anterior cerebral and anterior communicating arteries in perfusion‐fixed human brains by simultaneous injection of fluorescent dyes and a radio‐opaque substance in 5% gelatin. Territories were defined by ultraviolet illumination of dye and high‐resolution mammography of radio‐opaque substance. Brains were sectioned coplanar with the Talairach proportional grid system and vascular data were plotted, allowing for application to any human brain. The data suggest first that the lenticulostriate artery, recurrent artery of Heubner, and anterior choroidal artery supply distinct territories of the basal ganglia with minimal overlap and sparse anastomoses between major penetrating vessels. Individual territories are spatially consistent across brains and match the extent of major/minor infarcts. Second, branching patterns of parental, second‐, and third‐order vessels leading to circumscribed terminal vascular beds could account structurally for “lacunar” infarcts. Ann Neurol 2005

Improvement in papilledema and visual loss after endovascular stent placement in dural sinus thrombosis.

Objective : To report two cases of cerebral venous sinus thrombosis with papilledema and visual loss that improved after endovascular stent placement. Materials and methods : Retrospective case series from a tertiary ophthalmic center. Results : Two cases of venous sinus occlusion treated with angioplasty and stenting are described. Both cases experienced improvement in optic disc edema and visual function following the procedures. Conclusion : Endovascular stent placement may relieve increased intracranial pressure and papilledema caused by cerebral sinus thrombosis and may prevent further visual loss.

Atretic parietal cephalocele associated with sinus pericranii: Embryological consideration

We report a case of atretic parietal cephalocele with a persistent parietal falcine sinus and partial absence of the straight sinus. The direct puncture angiographic study demonstrated that there was a major venous channel through the parietal skull defect. From the embryological point of view, this association may provide us with possible pathoetiologic evidence of congenital sinus pericranii is one of the alternative venous drainage pathways to compensate venous outflow in the cases of intracranial developmental anomalies.

Outcomes for overlapping stents in the extracranial carotid artery

Various diseases of the carotid artery are treatable by stenting. However, few reports of overlapping carotid stents exist. As a result, the indications, long‐term outcomes, and potential complications of this technique remain largely unknown. We therefore present and examine a series of 11 patients treated by this unique stenting method. A retrospective single‐institution review was performed for patients in whom overlapping carotid stents were placed. Only patients with imaging follow‐up beyond 3 months were included. Of 38 patients who had extracranial carotid artery stents placed, 11 patients fulfilled the inclusion criteria for both overlapping stents and imaging follow‐up greater than 3 months (range, 0.4–3 years; mean, 1.3 years). Clinical follow‐up ranged between 0.4 and 3.6 years (mean, 2.1 years). Carotid pathology within this cohort included atheromatous stenosis (n = 3), recurrent stenosis following carotid endarterectomy (n = 2) or stenting (n = 1), postirradiation angiitis (n = 1), carotid artery kink created by initial stent placement (n = 2), and both traumatic (n = 1) and neoplastic (n = 1) carotid blowout syndrome. No permanent stroke or stenting‐related death occurred. Focal stenosis or intimal hyperplasia resulting in 35% or less luminal narrowing developed in three patients (27%) after tandem stenting. Overlapping stents provide a durable treatment for a variety of extracranial carotid pathologies. Clinically and hemodynamically significant (> 50%) poststenting stenosis or intimal hyperplasia did not occur in this series. Catheter Cardiovasc Interv 2004;62:375–379.

In Vitro Studies for Stent-Assisted Coiling of Terminus Aneurysms By Straight-On Intra-Aneurysmal Stent Deployment

OBJECTIVEnDeployment of a Neuroform microstent (NFM; Boston Scientific/Target, Freemont, California, USA) within acutely angled geometry may result in substantial deformations. This in vitro study was conducted to validate a novel alternative technique, consisting of intentional deployment of a NFM straight on into a terminus aneurysm, by assessing the mechanics, feasibility, and stability of the coils.nnnMETHODSnSilicon models of wide-neck terminus aneurysms were constructed. Straight-on deployment of a NFM from the afferent vessel into the aneurysm was compared with conventional cross-neck deployment at a right angle position followed by Guglielmi detachable coil embolization simulation. The supporting forces of the two different methods of deployment were compared by the use of side-wall eccentric and en-face compression tests.nnnRESULTSnStraight-on deployment of a NFM at a wide-neck terminus aneurysm was a relatively simple technique compared with cross-neck right angle deployment. Good stability of the coil mass was consistently achieved with adequate preservation of the parent vessel lumen. A larger residual neck space at the side without the stent and much coil mass protruding into the parent vessel were observed in cross-neck stent deployment. Compression tests revealed a larger supporting force of the NFM with straight-on deployment compared with the side-wall radial force (P < 0.05). A potential problem with this technique is the possible inability or difficulty in retrieving a partially deployed coil.nnnCONCLUSIONSnStent-assisted coiling of wide-neck terminus aneurysms with straight-on deployment of NFM consistently achieved a stable NFM-coil complex. The NFM also had a better supporting force in a straight position. Some technical difficulties may be encountered during subsequent coiling. This alternative technique to conventional cross-neck bridging appears to be another strategy for wide-neck terminus aneurysm coiling.