Robert W. Hurst

Spinal dural arteriovenous fistula The pathology of venous hypertensive myelopathy

Spinal dural arteriovenous fistulas (SDAVFs) are the most common type of spinal vascular malformation. The arteriovenous shunts, located entirely outside the spinal cord, cause a clinical picture of chronic progressive myelopathy believed to arise from the effects of increased venous pressure and impaired venous drainage on the spinal cord. Despite their well-described clinical and angiographic features, no reports have documented the spinal cord pathology in a case of angiographically or pathologically proven SDAVF. We report such a patient in whom a spinal cord biopsy supported increased venous pressure as a mechanism of neurologic dysfunction.

Hypertension, small size, and deep venous drainage are associated with risk of hemorrhagic presentation of cerebral arteriovenous malformations

OBJECTIVE To identify clinical and angiographic factors of cerebral arteriovenous malformations (AVMs) associated with hemorrhage to improve the estimation of the risks and help guide management in clinical decision making. METHODS We conducted a retrospective analysis of 100 consecutive adults who have presented during the past 3 years to our institution with cerebral AVMs. Angiographic and clinical parameters were evaluated using multivariate logistic regression analysis to analyze factors associated with hemorrhagic presentation. RESULTS The group had a mean age of 37.8 years; 53% were men, 48% presented with intracranial hemorrhage, and 40% presented with seizures. All 10 patients with cerebellar AVMs presented with hemorrhage. The following factors were independently associated with AVM hemorrhage: history of hypertension (P = 0.019; odds ratio [OR] = 5.36), nidal diameter <3 cm (P = 0.023: OR = 4.60), and deep venous drainage (P = 0.009: OR = 5.77). Dural arterial supply (P = 0.008; OR = 0.15) was independently associated with decreased risk of bleed. Location, nidal aneurysms, patient age, and smoking were not associated with increased or decreased bleeding risk. CONCLUSION In this study, we found small AVM size and deep venous drainage to be positively associated with AVM hemorrhage. Dural supply was associated with a decreased likelihood of hemorrhagic presentation. Hypertension was found to be the only clinical factor positively associated with hemorrhage, a finding not previously reported. Smoking, although associated with increased risk of aneurysmal subarachnoid hemorrhage, was not associated with a higher risk of AVM hemorrhage.

Arteriovenous Shunt Visualization in Arteriovenous Malformations with Arterial Spin-Labeling MR Imaging

BACKGROUND AND PURPOSE: A reliable quantitative technique for measuring arteriovenous (AV) shunt in vascular malformations is not currently available. Here, we evaluated the hypothesis that continuous arterial spin-labeled (CASL) perfusion MR imaging can be used to detect and measure AV shunt in patients with arteriovenous malformations (AVMs). MATERIALS AND METHODS: CASL perfusion MR imaging was performed in 7 patients with AVMs. Semiquantitative AV shunt estimates were generated based on a thresholding strategy by using signal-intensity difference (ΔM) images to avoid potential errors in cerebral blood flow (CBF) calculation related to abnormal transit times and nonphysiologic blood-tissue water exchange in and around the AVMs. The potential for measuring CBF in regions distant from and near the AVM was explored, as was the relationship of CBF changes related to the size of the shunt. RESULTS: In all 7 cases, striking increased intensity was seen on CASL perfusion ΔM maps in the nidus and venous structures draining the AVM. Shunt estimates ranged from 30% to 0.6%. Mean CBF measurements in structures near the AVMs were not significantly different from the contralateral measurements. However, CBF in adjacent ipsilateral white matter increased relative to the contralateral side as the percent shunt increased (P = .02). Cortical gray matter CBF Δ (contralateral-ipsilateral) values demonstrated the same effect, but the correlation was weak and not significant. Thalamic CBF decreased ipsilaterally with increasing percent AV shunt (P = .01), indicating a possible steal effect. Basal ganglia Δ values showed little change in CBF with the size of the AV shunt. CONCLUSION: CASL perfusion MR imaging can demonstrate AV shunting, providing high lesion conspicuity and a novel means for evaluating AVM physiology.

Endovascular stent treatment of cervical internal carotid artery aneurysms with parent vessel preservation

BACKGROUND Aneurysms involving the cervical portion of the internal carotid artery (ICA) frequently result from prior trauma or dissection. CASE DESCRIPTIONS Two patients are reported with cervical internal carotid artery aneurysms. In both cases, disease involving the contralateral ICA precluded safe treatment of the aneurysms by ICA occlusion. Endovascular stents placed across the diseased portion of the artery resulted in thrombosis of the aneurysm with preservation of the parent artery. CONCLUSION Endovascular stent placement should be considered for treatment of aneurysms involving the cervical ICA when preservation of the parent vessel is necessary.

Endovascular and surgical treatment of ruptured cerebral aneurysms in pediatric patients.

OBJECTIVEPediatric cerebral aneurysms are rare. There are very few recent studies that focus on the multidisciplinary treatment of ruptured aneurysms. We reviewed our pediatric endovascular and surgical experience with ruptured cerebral aneurysms. METHODSPediatric patients aged 16 years and younger who were admitted with a diagnosis of aneurysmal subarachnoid hemorrhage and treated at the Childrens Hospital of Philadelphia were included in this analysis. RESULTSTwelve patients with 13 aneurysms (4 male patients and 8 female patients; age range, 4 months–16 years; mean age, 5.1 years), were admitted with subarachnoid hemorrhage during the past 12 years. The majority of patients were admitted in good clinical condition; 31% were in Hunt and Hess Grade II, and 31% were in Hunt and Hess Grade III. The remaining patients were in poor clinical condition and were in Hunt and Hess Grade IV (23%) or Grade V (15%). Computed tomography revealed that 15% of the patients were in Fisher Grade 2, 23% were in Fisher Grade 3, and 62% were in Fisher Grade 4. Endovascular techniques were used in the treatment of 5 aneurysms, and microsurgery was used in the treatment of 8 aneurysms. In the endovascular group, aneurysm sizes ranged from 2 to 35 mm (mean, 12.6 mm); 3 aneurysms were in the anterior circulation, and 2 were in the posterior circulation. In the microsurgery group, 6 aneurysms were in the anterior circulation, and 2 were in the posterior circulation; sizes ranged from 3 to 15 mm (mean, 6.8 mm). Sixty-nine percent of the patients were independent at follow-up. CONCLUSIONContemporary endovascular and microsurgical techniques can be used effectively to treat ruptured cerebral aneurysms in pediatric patients. In the time period studied, the techniques were equally effective when used in the appropriate patients.

Alternative management considerations for ethmoidal dural arteriovenous fistulas

BACKGROUND Ethmoidal dural arteriovenous fistulas (EDAFs) are an unusual type of intracranial vascular lesion that commonly present with acute hemorrhage. They are often best treated surgically; however, recent endovascular advances raise questions concerning the best therapeutic approach. METHODS We present 7 cases of EDAFs managed at this institution over a 6-year period, which demonstrate the broad spectrum of clinical behavior associated with the lesions. Four patients presented with intracranial hemorrhage, 1 patient with rapidly progressive dementia, 1 patient with a proptotic, red eye, and 1 with a retro-orbital headache. RESULTS One patient underwent no treatment, 1 underwent embolization alone, 2 underwent embolization and resection, and 3 patients underwent resection alone. There was complete obliteration of the EDAF in all of the patients who underwent surgical resection. Embolization was performed through the external carotid circulation and not the ophthalmic artery. There were no treatment-related neurologic deficits. CONCLUSIONS Treatment is best managed with a multidisciplinary approach, which emphasizes complete resection of the lesions with assistance from interventional neuroradiology techniques. However, each patient must be evaluated independently as treatment may vary depending on the angioarchitecture of the lesion.

Topic review: surface modifications enhancing biological activity of guglielmi detachable coils in treating intracranial aneurysms

BACKGROUND Endovascular therapy with Guglielmi detachable coils is an accepted treatment option for patients with intracranial aneurysms. However, an emerging technology in the realm of endovascular tools is the use of traditional Guglielmi detachable coils with biologically active substances complexed to the coil surface to enhance aneurysm occlusion. METHODS We review the literature and current trends in modified Guglielmi detachable coils. Surface modifications with extracellular matrix proteins, growth factors, ion impregnation, and genetically altered cells have been used in animal studies to improve the cellular response of Guglielmi detachable coils. Similarly, coronary artery stents have been modified in several different ways to maintain vessel patency, contrary to the goal of endovascular therapy. We comparatively reviewed this literature to add insight into the evolution of the research on modified Guglielmi detachable coils. CONCLUSIONS Guglielmi detachable coil modifications have the potential to enhance aneurysm obliteration with directed cellular responses. This may allow aneurysm occlusion with coils in less time than untreated coils, thus decreasing the risks of aneurysm enlargement and hemorrhage.

Quality Improvement Guidelines for the Performance of Cervical Carotid Angioplasty and Stent Placement

Developed by a Collaborative Panel of the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, and the Society of Interventional Radiology

Quality improvement guidelines for the performance of cervical carotid angioplasty and stent placement: Developed by a collaborative panel of the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, and the Society of Interventional Radiology

John D. Barr, MD, John J. Connors, III, MD, David Sacks, MD, Joan C. Wojak, MD, Gary J. Becker, MD, John F. Cardella, MD, Bohdan Chopko, MD, PhD, Jacques E. Dion, MD, Allan J. Fox, MD, Randall T. Higashida, MD, Robert W. Hurst, MD, Curtis A. Lewis, MD, MBA, Terence A.S. Matalon, MD, Gary M. Nesbit, MD, J. Arliss Pollock, MD, Eric J. Russell, MD, David J. Seidenwurm, MD, and Robert C. Wallace, MD, for the ASITN, ASNR, and SIR Standards of Practice Committees

Carcinoid tumor of the sacrum: case report.

We present a case of isolated carcinoid tumor of the sacrum and highlight the unusual nature of this lesion. The histopathology suggests hindgut cause, and we discuss the possibility of an underlying congenital tailgut cyst. We review the pathology of these rare anomalies with reference to embryological development and known instances of carcinoid focus. We also present previous reports of sacral carcinoid.