Spontaneous intracranial hypotension: case series of rare clinical presentations.

BACKGROUND: Spontaneous intracranial hypotension (SIH) is an increasingly described entity, with over 70 cases reported in the literature. The classic triad includes orthostatic headache, diffuse pachymeningeal enhancement on magnetic resonance imaging (MRI) with gadolinium, and low cerebrospinal fluid pressure (CSF) in the lateral decubitus (< 60 mm H2O) and sitting positions. METHOD: We present four rare clinical presentations of SIH, two of which have not been previously described in the literature, to the best of our knowledge. RESULTS: Patient 1 presented with dyspnea, dysphagia, bilateral ptosis, diplopia and seizures. Patient 2 presented with a paradoxical positional pattern of orthostatic hypotension. In Patient 3, bilateral subdural hematomas (SDH) were encountered; while in Patient 4, a recurrent unilateral SDH requiring multiple surgical interventions was demonstrated. CONCLUSION: Although uncommon clinical presentations, all four cases of intracranial hypotension were spontaneous, demonstrated diagnostic MRI findings, and responded favorably to blood patches or saline injections.

Endovascular Coil Occlusion of a Traumatic Pseudoaneurysm of the Posterior Cerebral Artery: A Case Report

ABSTRACT A 51-year-old male developed traumatic pseudoaneurysms of the right- and left-posterior cerebral arteries following endoscopic resection of a pituitary adenoma. The right-sided aneurysm resolved spontaneously but the left progressed in size. This was treated endovascularly, with successful embolization of the sac. This is the first report of this approach to the management of a pseudoaneurysm of the posterior cerebral arteries to our knowledge.

Case of the month: April 1998--30 year old male with perineal numbness.

A 30-year-old male presented with a 2 year progressive course of bowel and bladder dysfunction, mild leg weakness and sensory abnormalities in sacral dermatomes. MRI showed an intra-axial conus medullaris lesion which was excised and identified as a ganglioglioma. The case presents the typical clinical course and histopathology of this unusual lesion which carries a favorable prognosis after gross total removal. Preoperative neurological function in such patients is highly predictive of post-operative outcome.

June 2001: 61 year old woman with confusion and obtundation.

The June COM. A 61 year old female presents with a three week history of increasing confusion, lethargy and headache. A neurological exam revealed disorientation, mild expressive aphasia, bilateral papilledema, and a right pronator drift. She had a craniotomy and resection of tumor. The tumor histologically was consistent with a solitary fibrous tumor displaying malignant features of hypercellularity, marked nuclear atypia, high mitotic activity, and a high proliferation index. This case is unique as the first malignant variant of solitary fibrous tumor to be reported intracranially.

Case of the month: June 1997--a 42 year old man with left facial weakness.

A 42 yr old male presented with left facial weakness. MRI showed lesions affecting the distal seventh nerve and third division of the trigeminal nerve. The seventh nerve was biopsied and showed a malignant epithelioid schwannoma. The patient underwent extensive resection followed by irradiation. This is one of very few examples of intracranial malignant peripheral nerve sheath tumors and the first reported example of an intracranial malignant epithelioid schwannoma. The literature is reviewed and completeness of resection appears to be the most pertinent prognostic factor.

Double microcatheter technique for detachable coil treatment of large, wide-necked intracranial aneurysms.

We describe a technique used to treat two patients with large, wide-necked aneurysms during the past 2 years. In the initial attempts at embolization, evidence of coil instability within the aneurysm or significant impingement of coil loops on the parent artery was observed. Advancement of a second microcatheter into the aneurysm allowed two coils to be braced across the aneurysmal neck before the detachment of either coil. This technique permitted successful coil treatment in both patients.

An analysis of the geometry of saccular intracranial aneurysms.

BACKGROUND AND PURPOSE: Our goal was to characterize the geometry of simple-lobed cerebral aneurysms and to find the absolute size of these lesions from angiographic tracings. METHODS: Measurements of angiographic neck width (N), dome height (H), dome diameter (D), and semi-axis height (S) were obtained from tracings of 87 simple-lobed lesions located at the basilar bifurcation (BB), middle cerebral (MCA), anterior communicating (AcomA), posterior communicating (PcomA), superior cerebellar (SCA), and posterior cerebral (PCA) arteries. The following ratios were analyzed as subgroups according to location and as a collective sample: dome diameter/dome height (D/H), dome height/neck width (H/N), dome diameter/neck width (D/N), and dome height/semi-axis height (H/S). Using the parent artery as a reference, aneurysm dimensions were normalized to absolute in vivo size. Estimations were validated using angiographic markers. RESULTS: For the entire sample, mean ratios were D/H = 1.11, D/N = 1.91, and H/N = 1.86. For the H/S ratio, the value was 1.98 for BB, MCA, and PcomA lesions and significantly smaller for the AcomA subgroup, at 1.52. The average sizes (in mm) for these dimensions were N = 3.4 for MCA, 3.0 for AcomA, 3.1 for PcomA, and 6.5 for BB; D = 6.1 for MCA, 5.9 for AcomA, 5.3 for PcomA, and 11.7 for BB; H = 5.6 for MCA, 5.0 for AcomA, 5.3 for PcomA, and 11.3 for BB. On average, BB aneurysms were twice as large as aneurysms at other locations. Good correlations were found between the scaled values for D and N, H and N, and H and D. CONCLUSION: These results have been used to characterize the typical simple-lobed aneurysm geometry and to provide a framework for the development of a method of assessment of treatment choice and outcome on the basis of lesion geometry.

Thromboembolic events associated with the treatment of cerebral aneurysms with Guglielmi detachable coils.

BACKGROUND AND PURPOSE: The purpose of this study was to document the prevalence, radiologic appearance, and treatment of thromboembolic events related to GDC embolization of cerebral aneurysms. METHODS: The clinical and radiologic records of all patients undergoing GDC treatment of intracranial aneurysms at our institution were reviewed. All cases in which unexpected complications occurred were selected. Those complications related to presumed thromboembolic events were analyzed. RESULTS: Of 59 patients (60 aneurysms) treated with GDCs, 17 (28%) experienced thromboembolic events. Seven patients had transient ischemic attacks and 10 had strokes. In 10 patients, the deficits occurred during or immediately after the procedure; in the rest, the complications were delayed. In six patients, all radiologic investigations were negative for infarction and in seven patients, CT scans showed new ischemic lesions. In four patients, MR imaging alone showed infarcts, and in four of nine patients who underwent subsequent angiography, acute ischemic findings were demonstrated. Eight patients were treated with volume expansion, eight with full heparinization, and one patient underwent intraarterial thrombolysis. Clinical outcome was excellent or good in 14 of 17 patients, with only three patients (5%) incurring permanent neurologic deficits. CONCLUSION: Thromboembolic events related to GDC treatment may be more common than has been reported in the literature. In our experience, this rate was 28%, with persisting deficits in 5%. These events can occur after uncomplicated procedures and may be unaccompanied by radiologic findings. Clinical outcome is usually favorable.

Use of a C-arm system to generate true three-dimensional computed rotational angiograms: preliminary in vitro and in vivo results.

PURPOSE: To evaluate the potential use of a C-arm mounted X-ray image intensifier (XRII) system to generate three-dimensional computed rotational angiograms during interventional neuroradiologic procedures. METHODS: A clinical angiographic system was modified to allow collection of sufficient views during selective intraarterial contrast injections for CT reconstruction of a 15 x 15 x 15-cm3 volume. Image intensifier distortion and C-arm instabilities were corrected by using image-based techniques. The impact of the pulsatile nature of the vessels during image data acquisition and of the presence of bone on the 3-D reconstructions was investigated by generating 3-D reconstructions of an anesthetized 20-kg pig and of a human skull phantom. RESULTS: A sequence of images sufficient for 3-D reconstruction was acquired in less than 5 seconds. Image intensifier distortion and C-arm instabilities were corrected to subpixel accuracy (0.035 mm and 0.07 mm, respectively). Both the intracranial vessels of the pig and the small, high-contrast structures in the skull were reconstructed with negligible artifacts. CONCLUSIONS: Using a C-arm mounted XRII system, computed rotational angiography can provide true 3-D images of diagnostic quality.

Symptomatic pulmonary complications from liquid acrylate embolization of brain arteriovenous malformations.

PURPOSE: To describe symptomatic pulmonary emboli from brain arteriovenous malformation embolization with liquid acrylates and to analyze the reasons for these complications and describe preventive techniques. METHODS: The clinical records of 182 patients embolized with acrylate glue since 1978 for treatment of brain AVMs were searched for evidence of symptomatic pulmonary complications. Originally iso-butyl-2-cyanoacrylate and more recently n-butyl-2-cyanoacrylate were used in all patients. Arteriovenous malformation morphology, amounts and techniques of glue injection, and clinical and radiologic investigations in the symptomatic patients were recorded. RESULTS: Three patients had pulmonary symptoms within 48 hours of glue injection. One patient with a left frontal arteriovenous malformation had embolization with an isobutyl-2-cyanoacrylate/pantopaque/acetic acid mixture; severe pleuritic chest pain developed 2 days later. One patient with a left temporal and one with a left cerebellar arteriovenous malformation had embolization with n-butyl-2-cyanoacrylate/lipiodol mixtures; a cough, pleuritic chest pain, and bloody sputum developed in both within 24 hours. Two patients experienced a significant drop in PO2. No flow-arrest techniques were used for any of the injections in these three patients. All patients demonstrated significant changes on chest x-ray and CT chest examinations. All were treated conservatively and recovered spontaneously. CONCLUSIONS: Symptomatic pulmonary complications can occur after acrylate glue injection, particularly when delivery systems without flow arrest are used in high-flow vascular brain lesions. Techniques using acetic acid to delay polymerization time and "sandwich" techniques in which glue is pushed with dextrose are also more susceptible to this complication.

Brain retractor edema during induced hypotension: the effect of the rate of return of blood pressure.

This study evaluated the hypothesis that the postoperative formation of cerebral edema may be influenced by the rate of blood pressure return after induced hypotension in a graded brain retractor injury. Nineteen cats underwent unilateral craniotomy, isoflurane-induced hypotension to a mean of 50 mm Hg, and application of a brain retractor at 20 mm Hg of pressure for 1 hour. Blood pressure was returned to normal either within 3 minutes or over 20 minutes. The degree of cerebral edema formation was determined by Evans blue dye and coronal magnetic resonance imaging. All animals showed extravasation of Evans blue dye in the retracted hemisphere that was most marked at the periphery of the retractor. T1 relaxation times were significantly prolonged in the retracted hemispheres of both the fast return and slow return groups (18.8% and 17.8%, respectively) and more so at the Evans blue sites (42.8% and 40.8%), although not so strikingly beneath the retractor itself (6.3% and 7.8%). T2 relaxation times were similarly prolonged but to approximately half the degree of the T1 times. In the nonretracted hemisphere, drug-induced hypotension alone did not result in significant acute cerebral edema or blood-brain barrier alteration. There was no significant difference between the fast and slow groups in Evans blue extravasation or magnetic resonance changes. Thus, in a retractor-induced brain injury, restoration of arterial pressure to normal either gradually or rapidly did not influence the degree or extent of edema formation.

Radical intracapsular removal of acoustic neurinomas. Long-term follow-up review of 11 patients.

Historically, the neurosurgical treatment of large acoustic neurinomas has developed with two principal goals: complete tumor removal and preservation of facial nerve function. A recent goal for small tumors is the preservation of hearing. Out of a personal series of 124 acoustic neurinomas treated over the past 35 years, the senior author has undertaken a radical intracapsular approach in 12 patients with large tumors (greater than 3 cm in diameter). Surgical indications for intracapsular removal included advanced age (five cases), the patient's wish to avoid any risk of facial paralysis (six cases), contralateral facial palsy (one case), and contralateral deafness (one case). Eleven of these 12 patients were available for follow-up review. Tumor recurrence developed in two patients (18%) at 2 and 3 years postoperatively; there were no late recurrences. Four patients died of unrelated causes, 10 to 19 years after surgery. The remaining five patients have survived a mean of 12 years since surgery without recurrence (range 3 to 22 years). Facial function was preserved in nine patients (82%). The results suggest that radical intracapsular removal may be the procedure of choice under certain circumstances and may offer an alternative to focused high-energy radiation.

Clinical presentation and management of giant anterior communicating artery region aneurysms.

OBJECT: The authors reviewed their 20-year experience with giant anterior communicating artery aneurysms to correlate aneurysm size with clinical presentation and to analyze treatment methods. METHODS: In 18 patients, visual and cognitive impairment were quantitated and clinical outcome was categorized according to the Rankin scale. Statistical analysis was performed using Fisher's exact test. CONCLUSIONS: At least 3.5 cm of aneurysm mass effect was required to produce dementia in the patient (p = 0.0004). Dementia was usually caused by direct brain compression by the aneurysm rather than by hydrocephalus. Optic apparatus compression occurred with smaller aneurysms (2.7-3.2 cm) when they pointed inferiorly. Aneurysm neck clipping was possible in half of the cases. Special techniques, including temporary clipping, evacuation of intraluminal thrombus, tandem and/or fenestrated clipping, and clip reconstruction were often required. Occlusion of or injury to the anterior cerebral artery (ACA) was the main cause of poor outcome or death. Proximal ACA occlusion, even of dominant A1 segments with small or no contralateral A1 artery, was an effective treatment alternative and was well tolerated as a result of excellent leptomeningeal collateral circulation.

Conservative treatment of acute spontaneous spinal epidural hematoma.

BACKGROUND: In cases of acute spontaneous epidural hematoma producing neurological deficits, emergency surgical evacuation is the standard treatment. METHODS: Such a case is presented in which complete resolution of neurological deficits occurred without surgical intervention. RESULTS: This is the fifth reported case of complete recovery in a patient managed conservatively. In most reports, significant and sustained neurological recovery had occurred with 12 hours of impairment of walking. CONCLUSION: In cases of acute spontaneous spiral epidural hematoma in which neurological deterioration is followed by early and sustained recovery, non-operative therapy may be considered.

Carotid stenting without angioplasty.

BACKGROUND: Carotid angioplasty and stenting is gaining popularity as an alternative to carotid endarterectomy for the treatment of carotid bifurcation stenosis. The major concern with the procedure is the risk of embolic stroke which may be initiated by balloon angioplasty of friable atherosclerotic plaque. Elimination of angioplasty may result in a lower incidence of embolic complications. METHOD: We describe a case in which a self-expanding stent alone, without balloon angioplasty, was used to successfully dilate an atherosclerotic stenosis of the carotid bifurcation. RESULTS: A moderate increase in vessel diameter, from 75% to 50%, was immediately observed after stent placement alone. No embolic complications were observed and follow-up plain film and ultrasound examinations showed progressive stent enlargement with excellent anatomic and hemodynamic results. CONCLUSIONS: In this case of severe carotid stenosis, the use of a self-expanding stent alone, without balloon angioplasty, resulted in excellent anatomic and hemodynamic improvement.

Endovascular therapy of a large vertebral artery aneurysm using stent and coils.

BACKGROUND: Endovascular therapy is becoming an increasingly popular treatment for cerebral aneurysms. Total angiographic occlusion of small-necked aneurysms (<4 mm) can be obtained in a high percentage of cases. The endovascular treatment of wide-necked or fusiform aneurysms remains a challenge with complete angiographic occlusion reported in <15% of cases. CASE REPORT: We describe the combined use of a flexible coronary stent and platinum coils to treat a wide-necked aneurysm of the distal left vertebral artery, in a patient with Grade IV subarachnoid hemorrhage. RESULTS: The procedure was technically successful as the parent artery was protected by the stent while coils were deposited in the aneurysm lumen. Although angiographic aneurysm occlusion was incomplete, the dome was packed with coils. No further hemorrhage has occurred. CONCLUSION: Combined endovascular stent and coil therapy is a promising technique for the treatment of wide-necked cerebral aneurysms.

Intracranial dural arteriovenous fistulae with pial venous drainage: combined endovascular-neurosurgical therapy.

BACKGROUND: Intracranial dural arteriovenous fistula with pial venous drainage may present with hemorrhage or focal neurologic deficit and may be difficult to treat. We wish to summarize the therapeutic approaches to these potentially dangerous lesions and to demonstrate how endovascular and neurosurgical therapies may have complimentary roles in their management. METHODS: The clinical and radiological records of all patients who presented to our institution with intracranial dural arteriovenous fistula over the last 5 years were reviewed. In those cases demonstrating pial venous drainage, details of presentation, imaging features, endovascular and surgical therapy and outcome were analyzed. RESULTS: We identified 13 patients with these lesions, 7 of whom presented with intracranial hemorrhage. Six patients were treated with embolization alone. Angiographic cure was achieved in 4. There was one complication in this group, a subarachnoid hemorrhage following glue injection. Four patients were treated with embolization followed by surgical occlusion of the pial venous drainage. Angiographic cure was achieved in all 4. There was one complication in this group, a facial nerve palsy following glue injection. Three patients were treated by surgery alone, with no complications and complete cure in all. CONCLUSION: Endovascular therapy of intracranial dural arteriovenous fistula may be curative but is often complex and carries definite risks. Neurosurgical ligation of pial draining veins, with pre-operative embolization when safe, may be a relatively more controlled method to achieve complete cure.

Combined endovascular/neurosurgical therapy of blister-like distal internal carotid aneurysms.

OBJECTIVE: To describe a novel therapeutic strategy for the treatment of "blister-like" aneurysms of the distal internal carotid artery (ICA). Direct surgical treatments of these fragile lesions have been associated with generally poor outcomes. METHODS: Two consecutive patients presenting with acute subarachnoid hemorrhage from "blister-like" aneurysms were treated with preliminary balloon occlusion of the ICA, followed by surgical trapping of the ICA beyond the aneurysm. RESULTS: The treatment resulted in complete thrombosis of both aneurysms with no clinical complications. CONCLUSION: This combined endovascular-neurosurgical approach offers a controlled, safer alternative to primary surgical therapy of "blister-like" aneurysms.

Hemichorea and hemiballismus: recent concepts.

An unusual case of severe hemichorea in an elderly hypertensive woman, precipitating acute pulmonary edema, is presented. There were small cystic infarctions in the contralateral neostriatum and thalamus, and intact subthalamic nuclei. The clinicopathologic correlation of hemichorea and hemiballismus is reviewed, and its relationship with the results of recent neuroanatomic research is discussed.