Aneurysms of the lateral spinal artery: report of two cases.

OBJECTIVE AND IMPORTANCE: The goal of this report was to describe aneurysms arising from the lateral spinal artery. The locations of aneurysms contributing to subarachnoid hemorrhage (SAH) have been well characterized and are primarily in the circle of Willis or at the bifurcation points of the internal carotid artery or the vertebrobasilar system. Although the spinal arteries are also in direct communication with the subarachnoid space, aneurysms of these arteries that lead to SAH are rare. To date, only aneurysms of the anterior and posterior spinal arteries have been described. In this communication, we report two patients with aneurysms of the lateral spinal artery who presented with SAH. CLINICAL PRESENTATION: Review of our neurointerventional database from 1997 to the present revealed two patients with lateral spinal artery aneurysms. The medical records, as well as the operative and radiological findings, were reviewed for both patients. In both cases, the lateral spinal arteries were involved as collateral pathways for occlusive vertebral lesions, suggesting hemodynamic stress as a cause. INTERVENTION: Endovascular treatment was attempted in both cases and was successful in one; open surgery, with aneurysm resection, was performed in the other case. We review the vascular anatomic features of the spinal cord as they relate to the lateral spinal artery, as well as treatment options for lateral spinal artery aneurysms. CONCLUSION: Lateral spinal artery aneurysms are a rare cause of SAH. Both endovascular and surgical treatment options are available.

Rheolytic thrombectomy of the occluded internal carotid artery in the setting of acute ischemic stroke.

BACKGROUND AND PURPOSE: Acute thromboembolic stroke complicated by ipsilateral carotid occlusion may present both mechanical and inflow-related barriers to effective intracranial thrombolysis. We sought to review our experience with a novel method of mechanical thrombectomy, in such cases, using the Possis AngioJet system, a rheolytic thrombectomy device. METHODS: A review of our interventional neuroradiology database revealed three patients in whom an occluded cervical internal carotid artery was encountered during endovascular treatment for acute stroke and in whom thrombectomy was attempted, using the 5F Possis AngioJet thrombectomy catheter. The medical records and radiographic studies of these patients were reviewed. RESULTS: Three patients were identified (ages, 52--84 years). Two patients had isolated occlusion of the internal carotid artery; in one patient, thrombus extended down into the common carotid artery. Treatment was initiated within 190 to 360 minutes of stroke onset. Thrombectomy of the carotid artery was deemed necessary because of poor collateral flow to the affected hemisphere (chronic contralateral internal carotid artery occlusion [one patient] and thrombus extending to the carotid "T" [one patient]) or inability to pass a microcatheter through the occluded vessel (one patient). Adjunctive therapy included pharmacologic thrombolysis with tissue plasminogen activator (all patients), carotid angioplasty and stenting (two patients), and middle cerebral artery angioplasty (one patient). Patency of the carotid artery was reestablished in two patients, with some residual thrombus burden. In the third patient, the device was able to create a channel through the column of thrombus, allowing intracranial access. CONCLUSION: Rheolytic thrombectomy shows potential for rapid, large-burden thrombus removal in cases of internal carotid artery thrombosis, allowing expedient access to the intracranial circulation for additional thrombolytic therapy.

Silent thromboembolic events associated with the treatment of unruptured cerebral aneurysms by use of Guglielmi detachable coils: prospective study applying diffusion-weighted imaging.

BACKGROUND AND PURPOSE: Aneurysm embolization using Guglielmi detachable coils (GDC) is gaining increasing acceptance as a viable alternative to surgery in the treatment of cerebral aneurysms. Although recent reports describe a significant rate of symptomatic thromboembolic complications with GDC use, many of the neurologic deficits are transient. We sought to determine the incidence of silent thromboembolic events with the use of diffusion-weighted imaging and to correlate radiologic findings with the results of neurologic examinations. METHODS: Diffusion-weighted MR imaging was performed within 48 hours in 14 consecutive elective GDC aneurysm treatments. Embolizations were performed under systemic heparinization; all flush solutions were heparinized, and both guiding catheters and microcatheters were placed for continuous heparinized infusions. Neurologic examination, including the National Institutes of Health Stroke Scale determination, was performed by a stroke neurologist before the coiling procedures were performed, immediately after the procedures were performed, and before discharge. MR imaging examinations were reviewed by a stroke neurologist and an interventional neuroradiologist, with determination and characterization of diffusion-weighted imaging abnormalities. RESULTS: Small areas of restricted diffusion, presumed to represent procedure-related embolic infarctions, were noted on the images of eight of 14 patients. All except one of the areas were located ipsilateral to the side of the catheterization. Six patients had evidence of multiple infarcts. Most lesions were small (<2 mm); one patient with coil stretch and herniation into the parent vessel had numerous infarcts with a dominant posterior frontal infarct. Pre- and posttreatment National Institutes of Health Stroke Scale scores were unchanged for 13 of 14 patients. Overall, the rate of asymptomatic emboli was 61% (eight of 13 treatments) in uncomplicated treatments. Strokes occurred independently of the number of coils used; the mean number of coils used for patients with strokes was 7.6 (range, two to 13) and for patients without evidence of infarcts was 10.2 (range, one to 30). This was not a significant difference (P > .5). CONCLUSION: Silent thromboembolic events related to the use of the GDC system are a common occurrence, despite meticulous technique and systemic anticoagulation. Although clinical sequelae are rare, the high rate of occurrence suggests that alterations in the technique, such as the addition of antiplatelet agents, should be considered.

Percutaneous transfemoral embolization of an indirect carotid-cavernous fistula with cortical venous access to the cavernous sinus. Case report.

The authors present the case of a 61-year-old man with an indirect carotid-cavernous fistula (CCF). Many now advocate a primary transvenous approach to deal with such lesions, with packing and thrombosis of the cavernous sinus leading to fistula obliteration. Transvenous access to the cavernous sinus via the inferior petrosal sinus is the usual route of access; both surgical and transfemoral superior ophthalmic vein approaches are also well described. In the case presented, the anatomy of the CCF was unfavorable for these approaches and its dominant venous egress was via a single enlarged arterialized cortical vein. The cavernous sinus was accessed with a transfemoral retrograde approach to the cortical draining vein. Successful CCF embolization was documented radiographically and clinically. To the authors' knowledge, this procedure has not been previously described in the English literature.

MR imaging of acute coccidioidal meningitis.

BACKGROUND AND PURPOSE: Our purpose was to describe the MR imaging findings in patients with acute coccidioidal meningitis. METHODS: Fourteen patients (11 men, three women; 22-78 years old; mean age, 47 years) with coccidioidal meningitis underwent neuroimaging within 2 months of diagnosis. Thirteen patients had MR imaging and one had an initial CT study with a follow-up MR examination 5 months later. Initial and follow-up MR images were evaluated for the presence of ventricular dilatation, signal abnormalities, enhancement characteristics, sites of involvement, and evidence of white matter or cortical infarction. The patterns of enhancement were characterized as focal or diffuse. Pathologic specimens were reviewed in two patients. RESULTS: Ten of the 14 images obtained at the time of initial diagnosis showed evidence of meningitis. All of the initially abnormal studies showed enhancement in the basal cisterns, sylvian fissures, or pericallosal region. Subsequent studies, which were available for three of the four patients with normal findings initially, all eventually became abnormal, with focal enhancement seen on the initial abnormal examination. Other abnormalities seen at presentation included ventricular dilatation (six patients) and deep infarcts (four patients). Pathologic specimens in two patients showed focal collections of the organism corresponding to the areas of intense enhancement on MR images. CONCLUSION: Early in its disease course, coccidioidal meningitis may show areas of focal enhancement in the basal cisterns, which may progress to diffuse disease. Pathologically, the areas of enhancement represent focal collections of the organism. Deep infarcts and communicating hydrocephalus are associated findings.

CT-guided pericardial drainage catheter placement with subsequent pericardial sclerosis.

Percutaneous drainage of malignant pericardial effusion is an established alternative to surgical pericardiotomy and pericardiectomy. We report the placement of a pericardial drainage catheter under CT guidance, with subsequent pericardial sclerosis. Previously described imaging modalities (fluoroscopy and ultrasound) used for the guidance of drain placement are compared and contrasted with our use of CT.

Three-dimensional computed tomography studies of the tendons of the foot and ankle.

Three dimensional (3D) reconstruction techniques were applied to serial computed tomography scans of a cadaveric foot. Subsequent manipulations of the image data on a 3D imaging workstation facilitated differentiation of tendon from surrounding tissue. Through the use of free-rotation and density thresholding, detailed 3D images of the major tendons were produced and displayed. The value of the technique for education and its potential for diagnosis is discussed.