Endovascular treatment for acute basilar thrombosis via a transradial approach: Initial experience and future considerations.

Acute basilar artery occlusion (BAO) secondary to emergent large vessel occlusion (ELVO) has an extremely poor natural history, with a reported mortality rate up to 95%. Mechanical thrombectomy in the setting of ELVO is generally performed via a transfemoral approach. However, radial access is increasingly being utilized as an alternative. We report our initial multi-institutional experience using primary radial access in the treatment of acute BAO in nine consecutive cases. Technical success defined as a TICI score of 2B or 3 was achieved in 89% of cases. Average puncture to revascularization time was 35.8 minutes. There were no complications related to radial artery catheterization. We contend radial access should potentially be considered as the first-line approach given inherent advantages over femoral access for mechanical thrombectomy for BAO.

Hyperacute Vasospasm After Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Cerebral vasospasm after aneurysmal subarachnoid hemorrhage typically occurs 3-14 days after aneurysm rupture. We describe a series of patients who developed vasospasm within minutes of aneurysm rupture. This phenomenon, which we term, "hyperacute vasospasm," has been reported in animal models of SAH, but hitherto has been poorly described in humans. METHODS: Eleven patients were identified from an institutional registry who had aneurysmal rupture during catheter cerebral angiography between 1997 and 2009. We quantified the degree of vasoconstriction using vascular diameter index (VDI). The change in VDI (delta VDI or DVDI) was calculated by determining the difference in VDI before and after the procedure. We also examined the relationship between hyperacute vasospasm and delayed cerebral ischemia. RESULTS: Ten of eleven (91%) patients with intraoperative aneurysm rupture had cerebral vasoconstriction within minutes of intra-procedural aneurysmal rupture. Six of eleven patients (55%) with hyperacute vasospasm developed delayed cerebral infarction. CONCLUSIONS: Hyperacute vasospasm is likely common in patients with intraoperative aneurysm rupture and may be an unrecognized element of the natural history of aneurysmal subarachnoid hemorrhage. In this limited series, there was an association between hyperacute vasospasm and delayed cerebral infarction.

Vertebral and Basilar Arteries: Transcranial Color-Coded Duplex Ultrasonography versus Conventional TCD in Detection of Narrowings.

We prospectively compared the accuracies of conventional transcranial Doppler ultrasound (TCD) and transcranial color-coded duplex sonography (TCCS) in the diagnosis of narrowing of the basilar (BA) and vertebral arteries (VA). Fifty-six consecutive patients (mean age 55.8 years; 34 women) after subarachnoid hemorrhage (n=46), stroke or transient ischemic attack (n=5), and for other reasons (n=5) underwent on the same day TCD, TCCS and the intra-arterial digital subtraction angiography (DSA) - the reference standard. The accuracy of peak-systolic (VPS), mean (VM), and end-diastolic velocities (VED) in detection of any arterial narrowing was estimated using the receiver operator characteristic (ROC) curve methodology and the total area (Az) under the curve. Accuracy of TCCS in detection of VA narrowing based on VPS and VM measurements was significantly higher than accuracy of TCD (Az=0.65 for VPS and Az=0.62 for VM versus Az=0.51 and Az=0.50, respectively, p<0.05 for both). Accuracy of TCCS in detection of BA narrowing was also higher than accuracy of TCD based on VPS measurements (Az=0.69 versus Az=0.50, respectively), with a trend toward significant difference, p=0.085. The accuracy of TCCS is superior to accuracy of TCD in detection of narrowings of vertebral and basilar arteries, thus TCCS should be preferred in routine clinical practice.

The role of time-resolved 3D contrast-enhanced MR angiography in the assessment and grading of cerebral arteriovenous malformations.

PURPOSE: To assess the role of three-dimensional (3D) contrast-enhanced, time-resolved MR angiography (CE TR MRA) in patients with intracranial arteriovenous malformations (AVMs). METHODS: We studied 12 patient with intracranial AVMs on a 3.0T MR imaging system (Magentom TIM Trio, Siemens Medical Solutions, Erlangen, Germany) using 3D CE TR MRA with autocalibrating partially parallel acquisitions and echo sharing schemes, which provided temporal resolution of 0.58 or 1.7s and near isotropic voxels. We qualitatively assessed image quality of the 3D CE TR MRA and compared the grading of the AVMs based on modified Spetzler-Martin system for 3D CE TR MRA and catheter digital subtraction angiography (DSA). RESULTS: CE TR MRA provided good quality images in the 3 standard orthogonal planes, and good arterial-venous separation in all cases. All AVMs were correctly graded by CE TR MRA when compared with DSA. 3D CE TR MRA provides a non-invasive alternative to DSA for the evaluation of cerebral AVMs.

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 (DeltaM) 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 DeltaM 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 Delta (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 Delta 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.

Development of a posterior cerebral artery aneurysm subsequent to occlusion of the contralateral internal carotid artery for giant cavernous aneurysm.

We report a case of a patient who developed a left posterior cerebral artery aneurysm 5 years after balloon occlusion of the right internal carotid artery for a giant cavernous aneurysm. The location of the new aneurysm was outside of the primary collateral pathways to the contralateral, proximally occluded, anterior circulation, illustrating the complexity of hemodynamic factors contributing to the development of intracranial saccular aneurysms. The appearance of an aneurysm in this setting supports the hypothesis that degenerative factors and hemodynamic stresses are important in the etiology of intracranial aneurysms.

Fatal rebleeding following coil embolization of cerebral aneurysms: the role of long-term systemic anticoagulation.

Embolization of cerebral aneurysms has become a common technique. Its impact on subsequent medical management of the patient is not well known. We report two patients who presented in a poor neurological grade after subarachnoid hemorrhage from posterior communicating artery aneurysms. Both were treated by coil embolization and both developed subclavian vein thrombosis, requiring systemic anticoagulation, initiated 11 and 21 days after embolization, respectively. Both developed a large, fatal intracranial hemorrhage adjacent to the embolized aneurysm in the fourth week of anticoagulation. Systemic anticoagulation of patients who have had a ruptured aneurysm treated by coil embolization may carry a significant risk of rebleeding. Alternate management strategies should be considered in these patients.

Mycotic aneurysm and cerebral infarction resulting from fungal sinusitis: imaging and pathologic correlation.

SUMMARY: A 73-year-old man was admitted with invasive aspergillus of the sphenoid sinus. Endoscopic debridement of the sphenoid sinus was complicated by rupture of a mycotic cavernous carotid artery aneurysm with severe epistaxis. The aneurysm was closed emergently by endovascular coil placement. Subsequently, the mycotic aneurysm extended intradurally and caused fatal subarachnoid hemorrhage. The radiologic-pathologic data illustrate the mechanism of fungal mycotic aneurysm formation and growth. This case emphasizes the need for rapid diagnosis of potential fungal involvement of the central nervous system and suggests the necessity for aggressive treatment once fungal cerebrovascular involvement is identified.

Extracranial aneurysms of the posterior inferior cerebellar artery.

OBJECTIVE: Extracranial aneurysms of the distal posterior inferior cerebellar artery (PICA) are extremely rare and sometimes difficult to diagnose without an adequate angiogram. We present the first series of 3 patients who were evaluated by the senior author and treated surgically. METHODS AND RESULTS: All 3 patients presented with subarachnoid hemorrhage (SAH). Clincial symptoms, included occipital headache, nuchal rigidity, abducens nerve palsy and rapid neurologic deterioration. A unilateral injection of the vertebral artery failed to show the distal contralateral PICA and the aneurysm in 1 patient. All patients underwent aneurysm clipping through a posterior fossa craniectomy and C-1 laminectomy. The aneurysms were located on the tonsillomedullary segment of the PICA, 10-12 mm below the level of the foramen magnum. CONCLUSIONS: It is important to adequately visualize the distal extent of both PICAs or these aneurysms may not be seen. Patients who present with SAH must have the entirety of both vertebral arteries evaluated to avoid missing these aneurysms. The aneurysms were located adjacent to the atlas necessitating an upper cervical laminectomy for adequate surgical exposure. In general, the patients did well postoperatively and none of the patients developed cerebral vasospasm.

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.

Peripheral spinal cord hypointensity on T2-weighted MR images: a reliable imaging sign of venous hypertensive myelopathy.

BACKGROUND AND PURPOSE: MR findings reported in conjunction with spinal dural arteriovenous fistula (SDAVF) include cord swelling, increased T2 signal within the spinal cord, and parenchymal enhancement, each of which is nonspecific. Enlarged vessels on the cord surface, the most specific MR finding, is noted in only half of SDAVF patients. Nevertheless, we have frequently observed MR peripheral hypointensity of the spinal cord in SDAVF on T2-weighted images, which is not characteristic of nonvascular or nonhemorrhagic causes of myelopathy and which has not been described in association with SDAVF. We hypothesized that peripheral cord hypointensity might reliably suggest the diagnosis of SDAVF or other causes of venous hypertensive myelopathy. METHODS: We reviewed the MR findings in 11 consecutive cases of angiographically confirmed symptomatic SDAVF and in four cases of intracranial dural arteriovenous fistula with spinal drainage, a lesion that also causes spinal cord deficits mediated by venous hypertensive myelopathy. RESULTS: In each case, T2 hypointensity involving the cord periphery was present. This sign has not been previously described in association with either SDAVF or other causes of venous hypertensive myelopathy. It appears, however, to be a relatively constant imaging feature of SDAVF. CONCLUSION: In the absence of spinal hemorrhage, T2 hypointensity involving the periphery of the spinal cord suggests venous hypertensive myelopathy as a cause of spinal cord dysfunction.

Orbital drainage from cerebral arteriovenous malformations.

OBJECTIVE: To describe the neuro-ophthalmic findings in patients with orbital drainage from cerebral arteriovenous malformations (AVMs). METHODS: We reviewed the records of 100 consecutive adult patients with cerebral AVMs who presented to our institution during a 4-year period. All patients with orbital drainage were identified, and their neuro-ophthalmic evaluations were reviewed. RESULTS: Three patients (3%) were identified with orbital drainage from a cerebral AVM. The first patient presented with typical chiasmal syndrome (reduced visual acuity, bitemporal hemianopia, and optic atrophy). Magnetic resonance imaging demonstrated a large left temporal and parietal lobe AVM with compression of the chiasm between a large pituitary gland and a markedly enlarged carotid artery. The second patient presented with headaches and postural monocular transient visual obscurations. Examination revealed normal visual function with minimal orbital congestion and asymmetrical disc edema, which was worse in the left eye. Magnetic resonance imaging revealed a large right parietal and occipital lobe AVM without mass effect or hemorrhage and an enlarged left superior ophthalmic vein. The third patient had no visual symptoms and a normal neuro-ophthalmic examination; a right parietal lobe AVM was discovered during an examination for the cause of headaches. CONCLUSION: Orbital drainage from cerebral AVMs is rare. Manifestations may include anterior visual pathway compression, dilated conjunctival veins, orbital congestion, and asymmetrical disc swelling.

Endovascular thrombolysis for symptomatic cerebral venous thrombosis.

OBJECT: The authors sought to treat potentially catastrophic intracranial dural and deep cerebral venous thrombosis by using a multimodality endovascular approach. METHODS: Six patients aged 14 to 75 years presented with progressive symptoms of thrombotic intracranial venous occlusion. Five presented with neurological deficits, and one patient had a progressive and intractable headache. All six had known risk factors for venous thrombosis: inflammatory bowel disease (two patients), nephrotic syndrome (one), cancer (one), use of oral contraceptive pills (one), and puerperium (one). Four had combined dural and deep venous thrombosis, whereas clot formation was limited to the dural venous sinuses in two patients. All patients underwent diagnostic cerebral arteriograms followed by transvenous catheterization and selective sinus and deep venous microcatheterization. Urokinase was delivered at the proximal aspect of the thrombus in dosages of 200,000 to 1,000,000 IU. In two patients with thrombus refractory to pharmacological thrombolytic treatment, mechanical wire microsnare maceration of the thrombus resulted in sinus patency. Radiological studies obtained 24 hours after thrombolysis reconfirmed sinus/vein patency in all patients. All patients' symptoms and neurological deficits improved, and no procedural complications ensued. Follow-up periods ranged from 12 to 35 months, and all six patients remain free of any symptomatic venous reocclusion. Factors including patients' age, preexisting medical conditions, and duration of symptoms had no statistical bearing on the outcome. CONCLUSIONS: Patients with both dural and deep cerebral venous thrombosis often have a variable clinical course and an unpredictable neurological outcome. With recent improvements in interventional techniques, endovascular therapy is warranted in symptomatic patients early in the disease course, prior to morbid and potentially fatal neurological deterioration.

Spinal cord arteriovenous fistulas involving the conus medullaris: presentation, management, and embryologic considerations.

BACKGROUND: Spinal cord arteriovenous fistulas (SCAVF) are uncommon congenital lesions that usually involve the most caudal aspects of the cord. We present three cases of SCAVF that illustrate the clinical manifestations and possible management options. The characteristic involvement of the conus medullaris and an associated tethered spinal cord in one of our patient suggests that a disorder of secondary neurulation may be involved in the formation of these arteriovenous shunt lesions. METHODS: Review of records and radiologic studies in three consecutive patients with SCAVF's treated at this institution. RESULTS: All three patients had SCAVF involving the lower lumbar spinal cord segments or the conus. One of the conus lesions was associated with tethering of the spinal cord. One small lesion (Type A) was treated surgically, whereas the two larger lesions (Type B) were treated using interventional neuroradiologic techniques. CONCLUSIONS: Both surgical and endovascular method have a role in management of these unusual spinal cord vascular malformations. The association with tethered cord suggests that the propensity for SCAVM to occur in the most caudal portions of the spinal cord may result from failure of secondary neurulation to properly develop the unique and complex vascular anatomy of the region.

Posttraumatic carotid-cavernous sinus fistula.

BACKGROUND AND OBJECTIVES: Posttraumatic carotid-cavernous sinus fistula is a rare complication of maxillofacial trauma and is seldom discussed in the literature. Motor vehicle accidents, falls, and other crush injuries contribute to the incidence of basilar skull fractures and the formation of fistulae. When injuries occur in the vessel wall, the carotid artery has the potential to fill the low-pressure cavernous sinus. The symptoms include chemosis, proptosis, pulsating exophthalmos, diplopia, ophthalmoplegia, orbital pain, audible bruits, and blindness. METHODS AND MATERIALS: The conventional treatments include carotid ligation and embolization. These techniques have often proved to be ineffective. A new method--the occlusive balloon technique--has been developed and is described in this article. A clinical case is used to illustrate the procedure. RESULTS AND/OR CONCLUSIONS: Utilization of balloon catheters provides a minimally invasive technique to treat patients, without significant morbidity or mortality. The procedure is found to be successful and predictable.