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1.
J Neurointerv Surg ; 5(6): 562-5, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23132531

ABSTRACT

BACKGROUND: Onyx is a liquid non-adhesive viscous embolic agent ideal for slow targeted injections which is currently approved for the treatment of intracranial aneurysms and arteriovenous malformations. METHODS: We performed a single-center retrospective analysis of consecutive patients who underwent off-label use of Onyx as the single embolic agent for the treatment of traumatic or infectious pseudoaneurysms involving the cerebral or cranial vasculature. RESULTS: A total of nine pseudoaneurysms treated by Onyx embolization were identified. Six of the pseudoaneurysms were post-surgical, one of the pseudoaneurysms was traumatic and two were infectious in nature. The mean pseudoaneurysm size was 5.9 mm (range 2-10 mm). Onyx-34 was used in all cases. Following treatment there was complete exclusion of all pseudoaneurysms including their inflow and outflow zones. CONCLUSIONS: Our experience demonstrates the efficacy and applicability of the use of Onyx in the treatment of complex traumatic and mycotic pseudoaneurysms involving the cerebral and cranial vascular tree.


Subject(s)
Aneurysm, Infected/therapy , Brain Injuries/complications , Dimethyl Sulfoxide , Embolization, Therapeutic/methods , Endovascular Procedures/methods , Intracranial Aneurysm/therapy , Polyvinyls , Adult , Aged , Aneurysm, False/complications , Anterior Cerebral Artery/pathology , Brain Neoplasms/complications , Brain Neoplasms/surgery , Carcinoma, Squamous Cell/complications , Central Nervous System Fungal Infections/pathology , Central Nervous System Fungal Infections/therapy , Cerebral Angiography , Cerebrovascular Circulation/physiology , Combined Modality Therapy , Endocarditis, Subacute Bacterial/complications , Female , Glioblastoma/complications , Glioblastoma/surgery , Humans , Intracranial Aneurysm/complications , Intracranial Aneurysm/etiology , Male , Middle Aged , Middle Cerebral Artery/pathology , Postoperative Complications/therapy , Retrospective Studies , Streptococcal Infections/complications , Treatment Outcome , Young Adult
2.
J Neurointerv Surg ; 5(2): 177-80, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22266792

ABSTRACT

Complete surgical resection of intra-axial hypervascular tumors located in the posterior fossa, in particular hemangioblastomas, may be challenging due to tumor location, mass effect and excessive bleeding. Embolization of these lesions can be done preoperatively or as a palliative measure in patients who are not surgical candidates. Preoperative embolization may reduce intraoperative blood loss, shorten surgical time and increase the chance of a complete resection. However, the safety and effectiveness of this procedure is still a matter of debate. Three cases of intra-axial hypervascular tumors in the posterior fossa (two confirmed hemangioblastomas) that were embolized using a non-adhesive liquid embolic agent (Onyx) are reported.


Subject(s)
Cerebellar Neoplasms/diagnostic imaging , Cerebellar Neoplasms/therapy , Dimethyl Sulfoxide/administration & dosage , Embolization, Therapeutic/methods , Hemangioblastoma/diagnostic imaging , Hemangioblastoma/therapy , Polyvinyls/administration & dosage , Adult , Aged , Humans , Male , Radiography
3.
BMC Neurol ; 10: 25, 2010 Apr 23.
Article in English | MEDLINE | ID: mdl-20416087

ABSTRACT

BACKGROUND: Conflicting data exists regarding the effect of hemispheric lateralization on acute ischemic stroke outcome. Some of this variability may be related to heterogeneous study populations, particularly with respect to the level of arterial occlusion. Furthermore, little is known about the relationship between stroke lateralization and predictors of outcome. The purpose of this study was to characterize the impact of stroke lateralization on both functional outcome and its predictors in a well-defined population of anterior circulation proximal artery occlusions treated with IAT. METHODS: Thirty-five consecutive left- and 35 consecutive right-sided stroke patients with intracranial ICA and/or MCA occlusions who underwent IAT were retrospectively analyzed. Ischemic change on pre-treatment imaging was quantified. Reperfusion success was graded using the Mori scale. Good outcome at three months was defined as an mRS

Subject(s)
Fibrinolytic Agents/therapeutic use , Functional Laterality/physiology , Stroke/therapy , Aged , Aged, 80 and over , Cerebral Angiography , Cohort Studies , Female , Functional Laterality/drug effects , Humans , Male , Middle Aged , Predictive Value of Tests , Reperfusion/methods , Retrospective Studies , Severity of Illness Index , Statistics, Nonparametric , Tomography, X-Ray Computed , Treatment Outcome
5.
Neurosurgery ; 64(1): E197-8; discussion E198, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19145148

ABSTRACT

OBJECTIVE: Spinal dural arteriovenous fistulae (SDAVF) are the most common variety of spinal vascular malformations. The Onyx liquid embolic system (ev3 Neurovascular, Irvine, CA) was recently approved for the treatment of intracranial arteriovenous malformations, but its use to treat SDAVFs is not yet well established. We report our initial experience with Onyx embolization in the treatment of SDAVFs. METHODS: Retrospective analysis of 3 consecutive patients with SDAVFs who were treated with the Onyx as the single treatment modality was performed. Demographic, clinical, and radiographic presentations as well as long-term outcomes were reviewed. RESULTS: Four procedures were performed in 3 patients. In all cases, transarterial microcatheterization was performed with a Marathon microcatheter (ev3 Neurovascular) and Onyx-18 (ev3 Neurovascular) was used. All 3 patients were men (age, 75-78 years) and presented with progressive myelopathy. Two patients underwent only 1 procedure, with a single pedicle embolized to achieve angiographic cure. In the remaining patient, 2 procedures with embolization through 3 different pedicles from 2 adjacent levels were necessary to achieve angiographic cure. No procedure-related complications were noted. No evidence of residual or recurrent SDAVF was seen on magnetic resonance imaging (mean, 10.6 months; range, 7.1-14.6 months), angiographic (mean, 12.2 months; range, 10.2-14.9 months), or clinical (mean, 13 months; range, 10.2-14.9 months) follow-up examination. CONCLUSION: Our initial experience suggests that the endovascular treatment of SDAVFs with the Onyx is feasible, safe, and highly effective, as it allows for a controlled penetration of the embolic agent into the draining vein. In this small series, we found no evidence of clinical, magnetic resonance imaging, or angiographic recurrence during the long-term follow-up period.


Subject(s)
Central Nervous System Vascular Malformations/therapy , Dimethyl Sulfoxide/therapeutic use , Embolization, Therapeutic/methods , Polyvinyls/therapeutic use , Spinal Cord/pathology , Aged , Angiography, Digital Subtraction , Follow-Up Studies , Humans , Male , Retrospective Studies
6.
J Neuroimaging ; 19(2): 183-4, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18681932

ABSTRACT

BACKGROUND AND PURPOSE: The most common causes of parkinsonism are degenerative and irreversible. Structural causes of reversible parkinsonism are exceptionally rare, but have been reported in association with deep cerebral venous thrombosis and dural arteriovenous fistula (DAVF). We now report a case of parkinsonian syndrome reversed by treatment of a dural arteriovenous malformation. METHODS: Case report with retrospective review of relevant clinical, imaging, and treatment data. RESULTS: A 79-year-old man presented with complaints of a slowly progressive parkinsonian syndrome and tinnitus. Brain magnetic resonance imaging (MRI) showed numerous serpiginous flow voids highly suggestive of a vascular malformation. Cerebral angiography revealed a Cognard grade IIa + b left transverse sinus DAVF. The patient underwent combined endovascular and surgical treatment in three stages over a week's time, with total obliteration of the DAVF and complete normalization of his symptoms and neurological examination. CONCLUSION: Although rare, DAVF should always be considered as a potential cause of progressive parkinsonism. This diagnosis is of great importance because of its potential reversibility.


Subject(s)
Central Nervous System Vascular Malformations/complications , Central Nervous System Vascular Malformations/therapy , Parkinsonian Disorders/etiology , Aged , Angiography, Digital Subtraction , Brain/blood supply , Brain/pathology , Central Nervous System Vascular Malformations/pathology , Cerebral Angiography , Humans , Magnetic Resonance Imaging , Male , Parkinsonian Disorders/pathology , Tinnitus/etiology , Tinnitus/pathology , Treatment Outcome
7.
Neuroradiology ; 50(4): 331-40, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18172631

ABSTRACT

INTRODUCTION: The use of coronary balloons in the cerebral vasculature is limited due to their poor trackability and increased risk of vessel injury. We report our experience using more compliant elastomer balloons for thrombus resistant to intraarterial (IA) pharmacological and mechanical thrombolysis in acute stroke. METHODS: We retrospectively analyzed 12 consecutive patients with an occluded intracranial artery treated with angioplasty using a low-pressure elastomer balloon. Angiograms were graded according to the Thrombolysis in Cerebral Infarction (TICI) and Qureshi grading systems. Outcomes were categorized as independent (modified Rankin scale, mRS, score

Subject(s)
Angioplasty, Balloon/instrumentation , Arterial Occlusive Diseases/therapy , Brain Ischemia/therapy , Elastomers , Stroke/therapy , Thrombolytic Therapy , Adult , Aged , Aged, 80 and over , Angioplasty, Balloon/methods , Arterial Occlusive Diseases/complications , Brain Ischemia/etiology , Cohort Studies , Combined Modality Therapy , Equipment Design , Female , Humans , Male , Middle Aged , Pressure , Retrospective Studies , Stroke/etiology , Treatment Outcome
8.
Neurocrit Care ; 7(3): 194-202, 2007.
Article in English | MEDLINE | ID: mdl-17901934

ABSTRACT

OBJECTIVE: To evaluate the safety of high-dosages of the endothelin ET(A/B )receptor antagonist bosentan in SAH patients at high-vasospasm risk. METHODS: Ten Fisher group-3 SAH patients, enrolled within 96 h of ictus, received bosentan in a dose-escalation manner (20, 30, 40 mg/kg/day orally every 4 hours on treatment days 1, 2, and 3 respectively, to a maximum dose of 4000 mg/day), followed by maintenance of the maximum tolerated dose until 14 days post-SAH or vasospasm resolution. Further management followed standard protocols: nimodipine in all patients; daily transcranial Doppler (TCD); "triple-H"/endovascular treatment, as indicated. RESULTS: Two of the ten patients never developed any clinical or TCD signs of vasospasm; the other eight patients exhibited some elevation of TCD velocities during the vasospasm watch period. Four of the eight patients remained asymptomatic; of them, one had only mild elevation on peak systolic velocities, thought to represent hyperemia. The other three were further assessed with CT-angiography; this revealed moderate vasospasm (asymptomatic) in only one patient. The remaining four patients developed symptomatic vasospasm requiring endovascular treatment; two developed cerebral infarction; both had started bosentan relatively later than the other subjects. The most common adverse drug effects were flushing and transient liver enzyme elevations, reversible in all. Two patients had ALT/AST elevations >3x normal limit, requiring bosentan-dose reduction or discontinuation (one case each). CONCLUSION: High-dose bosentan (up to 40 mg/kg/day) appears to be safe in SAH patients at high risk of developing vasospasm. Further studies are required to properly investigate the efficacy of this regimen in the prevention and treatment of SAH-induced vasospasm.


Subject(s)
Antihypertensive Agents/administration & dosage , Subarachnoid Hemorrhage/complications , Sulfonamides/administration & dosage , Vasospasm, Intracranial/drug therapy , Vasospasm, Intracranial/prevention & control , Adult , Bosentan , Cohort Studies , Dose-Response Relationship, Drug , Drug Administration Schedule , Feasibility Studies , Female , Humans , Male , Middle Aged , Pilot Projects , Subarachnoid Hemorrhage/drug therapy , Vasospasm, Intracranial/etiology
9.
J Magn Reson Imaging ; 26(4): 1112-6, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17896395

ABSTRACT

PURPOSE: To study the spontaneous low-frequency blood oxygenation level-dependent (BOLD) functional MRI (fMRI) signal fluctuations during hyperacute focal cerebral ischemia. MATERIALS AND METHODS: A stroke model in nonhuman primates (macaques) was used in this study. Spontaneous fluctuations were recorded using a series of gradient-recalled echo (GRE) echo-planar imaging (EPI) images. Fast Fourier transformation (FFT) was performed on the serial EPI data to calculate the frequency and magnitude of the spontaneous fluctuations. Diffusion tensor imaging (DTI) and perfusion-weighted imaging (PWI) were preformed to detect the ischemic lesion. RESULTS: The frequency of these fluctuations decreased in the periinfarct tissue in the ipsilateral hemisphere, while their magnitude increased. This area of abnormal signal fluctuations often extended beyond the hyperacute diffusion/perfusion abnormality. CONCLUSION: This study suggests that measurement of the spontaneous fMRI signal fluctuations provides different information than is available from diffusion/perfusion or T2-weighted MRI.


Subject(s)
Brain Ischemia/diagnosis , Brain Ischemia/pathology , Magnetic Resonance Imaging/methods , Acute Disease , Animals , Brain/pathology , Diffusion , Echo-Planar Imaging/methods , Fourier Analysis , Ischemia/pathology , Macaca , Male , Perfusion , Primates , Reproducibility of Results , Time Factors
10.
Surg Neurol ; 68(1): 19-23, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17586214

ABSTRACT

BACKGROUND: Aneurysm recanalization is a significant problem in coil-treated intracranial aneurysms. We hypothesize ruptured aneurysms are more likely to demonstrate this phenomenon than unruptured aneurysms. METHODS: This was a retrospective study over 4 years. Initial and follow-up angiography results were reviewed and aneurysm obliteration was classified: I, complete; II, residual neck; III, residual aneurysm; and IV, partial treatment. Recanalization was classified as significant, mild, and none. RESULTS: Two hundred twelve aneurysms were coiled in 199 patients, of which 180 patients survived to 6 months after treatment. Follow-up angiography (>6 months) was available for 116 (64.4%) aneurysms (44 ruptured, 72 unruptured). Mean angiographic follow-up was 20 months. Recanalization was significant in 16 (13.8%) aneurysms, mild in 23 (19.8%), and absent in 87 (75%). Sixteen aneurysms underwent recoiling. Factors significant for recanalization by univariate analysis were ruptured vs unruptured (53.5% vs 22.5%; P = .001), larger aneurysm size (t test, P < .0001; median, 8-mm cut point, P < .01), aneurysm location (basilar tip and ICA terminus, P < .05), posterior circulation (P < .05), and younger age (t test, P < .05), whereas aneurysm neck size (4 mm) demonstrated a trend (P = .09). Incomplete initial aneurysm obliteration (II-IV, 20.6% vs I, 4.3%; P < .05) was associated with significant recanalization. In multivariate analysis, younger age (age <52 years; OR, 2.4; 95% CI, 0.194-2.08), ruptured aneurysm (OR, 3.2; 95% CI, 1.25-8.13), and larger aneurysm size (OR, 1.14; 95% CI, 1.04-1.24 linearly; OR, 3.5; 95% CI, 1.38-8.72) significantly predicted aneurysm recanalization. Performance of recoiling was significant with larger aneurysm size (OR, 2.0; 95% CI, 0.02-3.25) and younger age (age <52, OR, 2.4; 95% CI, 0.34-3.31) by multivariate analysis, whereas ruptured aneurysm demonstrated a trend. CONCLUSIONS: In multivariate analyses, ruptured aneurysms, larger aneurysms, and younger patient age were significantly associated with recanalization. Larger aneurysms and younger age were significantly associated with recoiling.


Subject(s)
Aneurysm, Ruptured/therapy , Embolization, Therapeutic/instrumentation , Intracranial Aneurysm/therapy , Adult , Age Factors , Aged , Aneurysm, Ruptured/diagnostic imaging , Cerebral Angiography , Female , Follow-Up Studies , Humans , Intracranial Aneurysm/diagnostic imaging , Male , Middle Aged , Multivariate Analysis , Recurrence , Retreatment , Retrospective Studies , Treatment Failure
11.
Stroke ; 38(1): 138-45, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17122422

ABSTRACT

BACKGROUND AND PURPOSE: We measured the temporal evolution of the T2 and diffusion tensor imaging parameters after transient and permanent cerebral middle cerebral artery occlusion (MCAo) in macaques, and compared it to standard histological analysis at the study end point. METHODS: Stroke was created in adult male macaques by occluding a middle cerebral artery branch for 3 hours (transient MCAo, n=4 or permanent occlusion, n=3). Conventional MRI and diffusion tensor imaging scans were performed 0 (acute day), 1, 3, 7, 10, 17, and 30 days after MCAo. Animals were euthanized after the final scan and the brains removed for histological analysis. RESULTS: Apparent diffusion coefficient in the lesion was decreased acutely, fractional anisotropy was elevated, and T2 remained normal. Thereafter, apparent diffusion coefficient increased above normal, fractional anisotropy decreased to below normal, T2 increased to a maximum and then declined. Reperfusion at 3 hours accelerated these MRI changes. Only the fractional anisotropy value was significantly different between transient and permanent groups at 30 days. Final MRI-defined fractional lesion volumes were well correlated with corresponding histological lesion volumes. Permanent MCAO animals showed more severe histological damage than their transient MCAO counterparts, especially myelin damage and axonal swelling. CONCLUSIONS: Overall, the MRI evolution of stroke in macaques was closer to what has been observed in humans than in rodent models. This work supports the use of serial MRI in stroke studies in nonhuman primates.


Subject(s)
Brain Ischemia/pathology , Cerebral Cortex/pathology , Cerebral Infarction/pathology , Diffusion Magnetic Resonance Imaging/methods , Animals , Anisotropy , Brain Ischemia/physiopathology , Cerebral Arteries/pathology , Cerebral Arteries/physiopathology , Cerebral Cortex/blood supply , Cerebral Cortex/physiopathology , Cerebral Infarction/physiopathology , Diffusion , Disease Models, Animal , Infarction, Middle Cerebral Artery/pathology , Infarction, Middle Cerebral Artery/physiopathology , Macaca fascicularis , Male , Nerve Fibers, Myelinated/pathology
12.
Magn Reson Imaging ; 24(8): 1069-75, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16997077

ABSTRACT

This article presents a warping technique for correcting brain tissue distortion on magnetic resonance imaging (MRI) scans due to stroke lesion growth and for mapping MRI scans to histological sections. Meshes are imposed upon the images for feature specification, and these features are exactly matched in the different images to be mapped, while the other voxels are matched by interpolation. This technique was tested on serial MR images and histological sections that were acquired in a nonhuman primate model of stroke. This technique was able to deliver satisfactory warping results. It is simple and robust and can be utilized in many applications for comparison of multimodality medical images and histological sections.


Subject(s)
Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Stroke/pathology , Algorithms , Animals , Models, Neurological , Primates , Reproducibility of Results
13.
Pain Physician ; 9(3): 257-60, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16886035

ABSTRACT

BACKGROUND: We describe a case of perioperative Addisonian crisis induced by vertebral augmentation. While several complications of vertebral augmentation have been reported previously, related to the technical procedure, to our knowledge, perioperative Addisonian crisis from vertebral augmentation has not been reported in the literature. OBJECTIVE: To report an Addisonian crisis perioperative to vertebral augmentation. DESIGN: Case report. METHOD: Retrospective case review. RESULTS: The patient had a history of adrenal insufficiency treated previously with steroids. He developed an L3 vertebral compression fracture, failed conservative therapy and was eventually referred for vertebral augmentation. Immediately after starting the procedure, the patient developed profound hypotension unresponsive to intravenous fluids and vasopressors, consistent with Addisonian crisis. After intravenous steroids had resolved the Addisonian crisis, he underwent vertebral augmentation without further complication. CONCLUSION: Addisonian crisis may be triggered by vertebral augmentation. Practitioners need to recognize immediately this potentially lethal disorder in patients with known or suspected adrenal insufficiency and treat with intravenous hydrocortisone.


Subject(s)
Addison Disease/complications , Hypotension/etiology , Intraoperative Complications/etiology , Low Back Pain/surgery , Lumbar Vertebrae/surgery , Addison Disease/drug therapy , Aged, 80 and over , Fractures, Compression/complications , Fractures, Compression/surgery , Humans , Hypotension/drug therapy , Intraoperative Complications/drug therapy , Low Back Pain/etiology , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/injuries , Male , Radiography , Steroids/administration & dosage
14.
Neurosurgery ; 58(4): 602-11; discussion 602-11, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16575323

ABSTRACT

OBJECTIVE: Embolization is an important therapeutic modality in the multidisciplinary management of arteriovenous malformations (AVM); however, prior series have reported a wide variability in overall complication rates caused by embolization (10-50% neurological deficit, 1-4% mortality). In this study, we reviewed our experience with AVM embolization and analyzed factors that might predict complications and clinical outcomes after AVM embolization. METHODS: We analyzed our combined neurovascular unit's results with AVM embolization from 1993 to 2004 for the following outcomes measures: 1) clinically significant complications, 2) technical complications without clinical sequelae, 3) discharge Glasgow Outcome Scale score, and 4) death. To determine embolization efficacy, we analyzed perioperative blood transfusion and rate of AVM obliteration. Univariate and multivariate analyses were performed for patient age, sex, history of rupture, history of seizure, associated aneurysms, AVM size, deep venous drainage, eloquent location, Spetzler-Martin grade, number of embolization stages, number of pedicles embolized, and primary treatment modality. RESULTS: Over an 11 year period, 295 embolization procedures (761 pedicles embolized) were performed in 168 patients with embolization as the primary treatment modality (n = 16) or as an adjunct to surgery (n = 124) or radiosurgery (n = 28). There were a total of 27 complications in this series, of which 11 were clinically significant (6.5% of patients, 3.7% per procedure), and 16 were technical complications (9.5% of patients, 5.4% per procedure). Excellent or good outcomes (Glasgow Outcome Scale > or = 4) were observed in 152 (90.5%) patients. Unfavorable outcomes (Glasgow Outcome Scale 1-3) as a direct result of embolization were both 3.0% at discharge and at follow-up, with a 1.2% embolization-related mortality. In the 124 surgical patients, 96.8% had complete AVM obliteration after initial resection, and 31% received perioperative transfusion (mean 1.4 units packed red blood cells per surgical patient). Predictors of unfavorable outcome caused by embolization by univariate analysis were deep venous drainage (P < 0.05), Spetzler-Martin Grade III to V (P < 0.05), and periprocedural hemorrhage (P < 0.0001) and by multivariate analysis were Spetzler-Martin III to V (odds ratio 10.6, P = 0.03) and periprocedural hemorrhage (odds ratio 17, P = 0.004). CONCLUSION: In a single-center, retrospective, nonrandomized study, 90.5% of patients had excellent or good outcomes after AVM embolization, with a complication rate lower than previously reported. Spetzler-Martin grade III to V and periprocedural hemorrhage were the most important predictive factors in determining outcome after embolization.


Subject(s)
Embolization, Therapeutic/adverse effects , Embolization, Therapeutic/statistics & numerical data , Intracranial Arteriovenous Malformations/mortality , Intracranial Arteriovenous Malformations/therapy , Adolescent , Adult , Aged , Child , Confidence Intervals , Female , Humans , Male , Middle Aged , Multivariate Analysis , Odds Ratio , Predictive Value of Tests , Retrospective Studies , Treatment Outcome
15.
J Med Primatol ; 35(2): 78-86, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16556294

ABSTRACT

BACKGROUND: An intravascular stroke model designed for magnetic resonance imaging was developed in Macaca fascicularis (M. fascicularis) to characterize serial stroke lesion evolution. This model produces a range of stroke lesion sizes which closely mimics human stroke evolution. This paper describes the care of animals undergoing this stroke procedure, the range of outcomes we experienced and the cause of mortality in this model. METHODS: Anesthesia was induced with atropine and ketamine and maintained with isoflurane or propofol. Non-invasive blood pressure, oxygen saturation, heart rate, respiration rate, temperature and end tidal CO2 were monitored continuously. The stroke was created by occluding a distal branch of the middle cerebral artery. During catheter placement animals were heparinized and vasospasm was minimized using verapamil. RESULTS: Anesthetic induction and maintenance were smooth. Animals with small strokes showed very rapid recovery, were able to ambulate and self-feed within 2 hours of recovery. Animals with strokes of >or=4% of the hemispheric volume required lengthy observation during recovery and parenteral nutrition. Large strokes resulted in significant brain edema, herniation and brainstem compression. CONCLUSIONS: Intracerebral hemorrhage and or subarachnoid hemorrhage coupled with a stroke of any size was acutely fatal. In the absence of an effective acute stroke therapy, the spectrum of outcomes seen in our primate model is very similar to that observed in human stroke patients.


Subject(s)
Infarction, Middle Cerebral Artery/veterinary , Macaca fascicularis/physiology , Stroke/veterinary , Animals , Blood Pressure/physiology , Body Temperature/physiology , Disease Models, Animal , Heart Rate/physiology , Infarction, Middle Cerebral Artery/physiopathology , Magnetic Resonance Imaging/veterinary , Male , Respiration , Stroke/physiopathology
16.
Neurosurgery ; 57(5): 845-9; discussion 845-9, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16284554

ABSTRACT

OBJECTIVE: Our practice has been to heparinize patients for cerebral aneurysm coiling even after recent external ventriculostomy drain (EVD) placement. The current medical literature cites a 12.5% symptomatic hemorrhage rate with heparinization after recent EVD placement. We reviewed our experience to determine our level of safety with this practice. METHODS: A search of our prospectively collected computerized aneurysm database revealed that from February 1998 to February 2004, 356 aneurysms were coiled, of which 119 patients had had recent EVD placement before coiling. During the same time period, 251 subarachnoid hemorrhage patients underwent EVD placement without coiling or heparinization. We reviewed the head computed tomographic scan reports and medical records to determine the incidence of EVD-related hemorrhage in heparinized patients compared with nonheparinized patients. RESULTS: There was only 1 patient in the heparinized group who had a symptomatic EVD-related hemorrhage attributable to heparinization (0.8%) and 11 patients with asymptomatic EVD-related hemorrhage (9.2%). Among the nonheparinized patients, there were 3 patients who had symptomatic EVD-related hemorrhages (1.2%) and 22 patients with asymptomatic EVD-related hemorrhages (8.8%) (P = not significant for both symptomatic and asymptomatic EVD-related hemorrhages). The time interval between EVD placement and heparinization in the heparinized patient with symptomatic EVD-related hemorrhage was 0.5 day; the mean time interval in the heparinized patients with asymptomatic EVD-related hemorrhage was 0.8 day; and in the heparinized patients with no hemorrhage, it was 0.8 day. The peak activated prothrombin time of the heparinized patient with symptomatic EVD-related hemorrhage was >150 seconds, the mean peak activated prothrombin time of the heparinized patients with asymptomatic EVD-related hemorrhage was 73.1 seconds, and that of the heparinized patients with no hemorrhage was 90.3 seconds. CONCLUSION: Heparinization for cerebral aneurysm coiling can be safely performed even after EVD placement within 24 hours, particularly if the activated prothrombin time is kept strictly controlled.


Subject(s)
Anticoagulants/therapeutic use , Coated Materials, Biocompatible , Heparin/therapeutic use , Intracranial Aneurysm/drug therapy , Intracranial Aneurysm/surgery , Ventriculostomy/methods , Adult , Aged , Aged, 80 and over , Drainage/methods , Female , Humans , Intracranial Aneurysm/pathology , Intracranial Aneurysm/psychology , Male , Middle Aged , Prospective Studies , Time Factors , Tomography, X-Ray Computed/methods , Treatment Outcome
17.
J Magn Reson Imaging ; 22(4): 461-6, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16142700

ABSTRACT

PURPOSE: To study a new gadolinium (Gd) contrast agent-NMS60-for MR perfusion-weighted imaging (PWI) of brain tissue. MATERIALS AND METHODS: NMS60 is a Gd3+ trimer with a molecular weight of 2158 Daltons, and a T2 relaxivity almost three times higher than that of Gd-DTPA. Middle cerebral artery (MCA) occlusion was induced in nine nonhuman primates. The animals were scanned acutely and for up to six follow-up time points. PWI peak, and time-to-peak maps were generated, and perfusion deficit volumes were measured from these maps. The values of peak, time-to-peak, and perfusion deficit volume were compared between NMS60 and GD-DTPA. RESULTS: These results demonstrate that there was no significant difference in our calculated perfusion parameters between the two contrast agents. CONCLUSION: The two agents were found to be equally effective for PWI for acute and chronic stroke in primates. Along with its previously demonstrated advantage for T1-enhanced imaging, the current results show that NMS60 is a viable contrast agent for use in stroke patients.


Subject(s)
Brain Ischemia/diagnosis , Contrast Media , Gadolinium DTPA , Magnetic Resonance Angiography/methods , Organometallic Compounds , Animals , Infarction, Middle Cerebral Artery/diagnosis , Macaca , Male
18.
Neurosurgery ; 57(2): 243-8; discussion 243-8, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16094152

ABSTRACT

OBJECTIVE: Heparin-induced thrombocytopenia Type II (HIT II) is the autoimmune-mediated severe form of the disease characterized by a significant reduction in platelets, and it carries a high risk of "paradoxical" serious thrombotic complications. Although HIT II has been studied in several different patient populations, the incidence of HIT II and the rate of thrombotic complications have never been reported in a neurosurgical patient population. Subarachnoid hemorrhage (SAH) patients, among neurosurgical patient populations, have a high exposure to heparin because they are in critical care units and have indwelling vascular catheters. In addition, the increase in neuroendovascular procedures with the associated use of heparinization will increase the exposure of SAH patients to heparin. METHODS: During a 3.5-year period (January 2000-June 2003), 389 consecutive SAH patients were treated at our center. We retrospectively reviewed their laboratory data and medical records and used accepted clinical criteria for the diagnosis of HIT II to determine the incidence of HIT II, thrombotic complications, management, and outcome. RESULTS: Fifty-nine patients (15%) met the clinical diagnostic criteria for HIT II. The average platelet count nadir in the HIT II patients was 68,600 +/- 25,300/microl (mean +/- standard deviation). Female patients and patients with Fisher Grade 3 were more likely to develop HIT II (P < 0.01). Thirty-six patients (61%) underwent a neuroendovascular procedure. The rate of systemic thrombotic complications in the HIT II patients was 37 versus 7% in SAH patients without HIT II (P < 0.001), and the rate of new hypodensities on head computed tomographic scans was 66% in the HIT II patients versus 40% in the SAH patients without HIT II (P < 0.001). Clinical outcomes were worse in the HIT II patients. The outcome was favorable for 38% in the HIT II patients versus 52% in all SAH patients (P < 0.05), and deaths were more common (29%) in the HIT II patients than in all SAH patients (12%, P < 0.001). CONCLUSION: The incidence of HIT II in SAH patients at a single center was 15%. The SAH patients with HIT II had significantly higher rates of thrombotic complications, new hypodensities on head computed tomographic scans, more deaths, and significantly less favorable outcomes. This is the first report of the incidence of HIT II in a neurosurgical patient population.


Subject(s)
Fibrinolytic Agents/adverse effects , Heparin/adverse effects , Purpura, Thrombocytopenic, Idiopathic , Aged , Blood Platelets/metabolism , Female , Humans , Incidence , Male , Middle Aged , Platelet Factor 4/metabolism , Purpura, Thrombocytopenic, Idiopathic/chemically induced , Purpura, Thrombocytopenic, Idiopathic/complications , Purpura, Thrombocytopenic, Idiopathic/epidemiology , Retrospective Studies , Sex Factors , Subarachnoid Hemorrhage/drug therapy , Subarachnoid Hemorrhage/epidemiology , Time Factors
19.
Pain Physician ; 8(4): 363-7, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16850059

ABSTRACT

BACKGROUND: Percutaneous kyphoplasty using a bone expander polymer device, such as percutaneous vertebroplasty and balloon kyphoplasty, is a therapeutic intervention for painful osteoporotic vertebral body compression fractures. Typically the procedure involves placement of bilateral Sky Bone Expanders in the fractured vertebral body via a transpedicular approach. We describe performance of "SKy"phoplasty using the Disc-O-Tech Sky Bone Expander (Disc-O-Tech Medical Technologies, Herzliya, Israel, and Monroe Township, New Jersey) via a unilateral transpedicular approach. The advantage of a unilateral approach is that it reduces the risks associated with large-bore needle placement. These risks include pedicle fracture, medial transgression of the pedicle or transgression into the spinal canal, nerve injury, cement leakage along the cannula tract, and spinal epidural hematoma. Additionally, using a unilateral approach reduces operative time and costs. CASE ILLUSTRATION: A 68-year-old man with osteoporosis presented with severe upper back pain which occurred following a fall. The pain was reproducible on palpation of the L1 spinous process. A lumbar spine magnetic resonance imaging (MRI) with STIR (short tau inversion recovery) sequence demonstrated an acute L1 vertebral body compression fracture. A L1 "SKy"phoplasty was performed using a single Sky Bone Expander polymer device via a unilateral transpedicular approach. The patient reported immediate relief of pain after the procedure. He denied any residual back pain at his follow-up visit. He was able to resume his normal activities including walking, which had been inhibited by pain prior to the procedure. CONCLUSION: "SKy"phoplasty can be performed using a single Sky Bone Expander via a unilateral pedicular approach. The key is a medial needle trajectory with a final Sky Bone Expander position in the midline of the vertebral body.

20.
Neurosurgery ; 55(4): 779-86; discussion 786-9, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15458586

ABSTRACT

OBJECTIVE: Although several recent studies have suggested that the incidence of vasospasm after aneurysmal subarachnoid hemorrhage is lower in patients undergoing aneurysmal coiling as compared with clipping, other studies have had conflicting results. We reviewed our experience over 8 years and assessed whether clipping, craniotomy, or coiling affects patient outcomes or the risk for vasospasm. METHODS: We included 515 patients with aneurysmal subarachnoid hemorrhage, identified prospectively from November 2000 to February 2003 (243 patients) and retrospectively from November 1995 to October 2000 (272 patients), by using International Classification of Diseases, 9th Revision, codes for subarachnoid hemorrhage. We classified patients as follows: clipping (413 patients), coiling (79 patients), and craniotomy (436 patients, including all 413 patients who underwent clipping plus 23 who underwent coiling as well as craniotomy for various reasons). We studied four outcome measures: total vasospasm, symptomatic vasospasm, poor outcome (modified Rankin score 3-6), and in-hospital mortality. To assess the risk of total vasospasm and symptomatic vasospasm, we performed multivariate regression analyses adjusting for age, Fisher grade, Hunt and Hess grade, aneurysm location (anterior versus posterior circulation), and aneurysm treatment modality. To assess the risk for poor outcome and in-hospital mortality, we adjusted for all the above variables as well as for total and symptomatic vasospasm. RESULTS: In the clipping group there was 63% total vasospasm and 28% symptomatic vasospasm; in the coiling group there was 54% total vasospasm and 33% symptomatic vasospasm; and in the craniotomy group there was 64% total vasospasm and 28% symptomatic vasospasm. In the multivariate analysis, age <50 years (P = 0.0099) and Fisher Grade 3 (P < 0.00001) predicted total vasospasm, and Fisher Grade 3 (P < 0.000001) and Hunt and Hess Grade IV or V (P = 0.018) predicted symptomatic vasospasm. Predictors of poor outcome were age >or=50 years (P < 0.0001), Fisher Grade 3 (P = 0.0072), Hunt and Hess Grade IV or V (P < 0.00001), symptomatic vasospasm (P < 0.0001), and coiling (P = 0.0314 versus clipping and P = 0.045 versus craniotomy). Predictors of in-hospital mortality were age >or= 50 years (P = 0.0030), Hunt and Hess Grade IV or V (P = 0.0001), symptomatic vasospasm (P < 0.00001), and coiling (P = 0.008 versus clipping and P = 0.0013 versus craniotomy). There was no significant difference in total vasospasm or symptomatic vasospasm when patients who underwent clipping or craniotomy were compared with patients who underwent coiling. In patients with Hunt and Hess Grade I to III ("good grade"), clipping and craniotomy were associated with better outcome and less in-hospital mortality, but there was no difference in total vasospasm or symptomatic vasospasm versus coiling. In patients with Hunt and Hess Grade IV or V ("poor grade"), there was no difference in any outcome measure among the treatment groups. CONCLUSION: In a single-center, retrospective, nonrandomized study, performance of clipping and/or craniotomy had significantly better outcome and lower mortality at discharge than coiling in good-grade patients but had no effect on total vasospasm or symptomatic vasospasm in good- or poor-grade patients.


Subject(s)
Craniotomy/methods , Embolization, Therapeutic/methods , Subarachnoid Hemorrhage/complications , Vasospasm, Intracranial/surgery , Vasospasm, Intracranial/therapy , Female , Humans , Male , Middle Aged , Prospective Studies , Retrospective Studies , Subarachnoid Hemorrhage/mortality , Subarachnoid Hemorrhage/surgery , Subarachnoid Hemorrhage/therapy , Treatment Outcome , Vasospasm, Intracranial/etiology , Vasospasm, Intracranial/mortality
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