25 results on '"Thorell W"'
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2. Diffuse anaplastic leptomeningeal oligodendrogliomatosis mimicking neurosarcoidosis
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Leep Hunderfund, A. N., primary, Zabad, R. K., additional, Aksamit, A. J., additional, Morris, J. M., additional, Meyer, F. B., additional, Thorell, W. E., additional, Parisi, J. E., additional, and Giannini, C., additional
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- 2013
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3. Successful Endovascular Treatment of Pulsatile Tinnitus Caused by a Sigmoid Sinus Aneurysm.
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Gard, A. P., Klopper, H. B., and Thorell, W. E.
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CEREBRAL angiography ,ANEURYSMS ,THERAPEUTIC embolization ,TINNITUS ,QUALITATIVE research ,PATIENTS - Abstract
We describe the case of a 48-year-old woman who presented with a sigmoid sinus aneurysm. These rare entities have only recently been described in the literature and the ideal treatment approach has not been elucidated. This report represents additional evidence in a growing body of literature that suggests that endovascular therapy is a safe and effective therapeutic alternative to surgical reconstruction of the sigmoid sinus in selected cases of intractable pulsatile tinnitus. [ABSTRACT FROM AUTHOR]
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- 2009
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4. Aneurysmal Subdural Hematoma: A Systematic Review.
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Aladawi M, Elfil M, Najdawi ZR, Ghaith H, Sayles H, Thorell W, and Hawkes MA
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- Humans, Hematoma, Subdural etiology, Aneurysm, Ruptured surgery, Aneurysm, Ruptured complications, Intracranial Aneurysm complications, Intracranial Aneurysm surgery, Subarachnoid Hemorrhage therapy, Subarachnoid Hemorrhage etiology
- Abstract
Background: Aneurysmal subdural hematoma (aSDH) is a rare complication of aneurysm rupture, affecting between 0.5 and 7.9% of patients with aneurysmal subarachnoid hemorrhage (aSAH). The clinical presentation, course, and outcomes of these patients are largely unknown., Objective: This study aims to systematically review the literature to evaluate the demographics, clinical presentation, aneurysm location, treatment options, and outcomes of patients with aSDH with and without aSAH., Methods: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we conducted a systematic review of three databases (PubMed, EMBASE, and Google Scholar). From identified reports, we extracted data on patients' demographics, clinical presentation, imaging findings, surgical interventions, and clinical outcomes. We compared clinical outcomes, need for surgical treatment, and aneurysm location between patients with aSDH with and without concurrent aSAH using χ
2 and Fisher's exact tests. We used simple and multivariable logistic regression models to further examine the association between the presence of aSAH and surgical treatment with clinical outcomes., Results: We identified 112 articles with a total of 270 patients (70% women, mean age 52.8 [± 15.5] years). The most common aneurysm locations were the middle cerebral artery, followed by the posterior communicating artery, and the internal carotid artery. Patients with isolated aSDH fully recovered more frequently than those with concomitant aSAH (38% vs. 6%). The presence of aSAH increased the odds of unfavorable outcome (odds ratio [OR] 2.68, 95% confidence interval [CI] 1.34-5.37). Surgical treatment was inversely associated with unfavorable outcome in the univariable (OR 0.48, 95% CI 0.28-0.84) but not in the multivariable analysis (OR 0.76, 95% CI 0.35-1.66)., Conclusion: aSDH occurs infrequently. Simultaneous presence of both aSDH and aSAH from an aneurysmal source is associated with poor outcomes. Surgical treatment is associated with lower rates of unfavorable outcomes including death and severe disability., (© 2024. Springer Science+Business Media, LLC, part of Springer Nature and Neurocritical Care Society.)- Published
- 2024
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5. Effects of Acute Intracranial Pressure Changes on Optic Nerve Head Morphology in Humans and Pig Model.
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Kedar S, Tong J, Bader J, Havens S, Fan S, Thorell W, Nelson C, Gu L, High R, Gulati V, and Ghate D
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- Animals, Humans, Intracranial Pressure physiology, Intraocular Pressure, Swine, Tomography, Optical Coherence, Tonometry, Ocular, Optic Disk
- Abstract
Purpose: The lamina cribrosa (LC) is a layer of fenestrated connective tissue tethered to the posterior sclera across the scleral canal in the optic nerve head (ONH). It is located at the interface of intracranial and intraocular compartments and is exposed to intraocular pressure (IOP) anteriorly and intracranial pressure (ICP) or Cerebrospinal fluid (CSF) pressure (CSFP) posteriorly. We hypothesize that the pressure difference across LC will determine LC position and meridional diameter of scleral canal (also called Bruch's membrane opening diameter; BMOD)., Methods: We enrolled 19 human subjects undergoing a medically necessary lumbar puncture (LP) to lower CSFP and 6 anesthetized pigs, whose ICP was increased in 5 mm Hg increments using a lumbar catheter. We imaged ONH using optical coherence tomography and measured IOP and CSFP/ICP at baseline and after each intervention. Radial tomographic ONH scans were analyzed by two independent graders using ImageJ, an open-source software. The following ONH morphological parameters were obtained: BMOD, anterior LC depth and retinal thickness. We modeled effects of acute CSFP/ICP changes on ONH morphological parameters using ANOVA (human study) and generalized linear model (pig study)., Results: For 19 human subjects, CSFP ranged from 5 to 42 mm Hg before LP and 2 to 19.4 mm Hg after LP. For the six pigs, baseline ICP ranged from 1.5 to 9 mm Hg and maximum stable ICP ranged from 18 to 40 mm Hg. Our models showed that acute CSFP/ICP changes had no significant effect on ONH morphological parameters in both humans and pigs., Conclusion: We conclude that ONH does not show measurable morphological changes in response to acute changes of CSFP/ICP. Proposed mechanisms include compensatory and opposing changes in IOP and CSFP/ICP and nonlinear or nonmonotonic effects of IOP and CSFP/ICP across LC.
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- 2022
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6. Colloid Brain Cyst
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Tenny S and Thorell W
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The colloid cyst is a benign growth usually located in the third ventricle and at or near the foramen of Monroe, which is at the anterior aspect of the third ventricle of the brain. The colloid cyst is an epithelial-lined cyst filled with gelatinous material. The gelatinous material commonly contains mucin, old blood, cholesterol, and ions. Colloid cysts can cause various symptoms, including headaches, diplopia, memory issues, and vertigo. Rarely colloid cysts have been cited as a cause of sudden death. When colloid cysts are symptomatic, they most commonly cause headaches, nausea, and vomiting secondary to obstructive hydrocephalus. The obstructive hydrocephalus is precipitated by blocking the egress of cerebrospinal fluid (CSF) from the lateral ventricles at the foramen of Monro, which connects the lateral and third ventricles., (Copyright © 2022, StatPearls Publishing LLC.)
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- 2022
7. Mannitol
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Tenny S, Patel R, and Thorell W
- Abstract
Mannitol can be used for the reduction of intracranial pressure and brain mass, to reduce intraocular pressure if this is not achievable by other means, to promote diuresis for acute renal failure to prevent or treat the oliguric phase before irreversible damage, and to promote diuresis to promote excretion of toxic substances, materials, and metabolites. There are also multiple uses of mannitol that are not FDA-approved. This activity will highlight the mechanism of action, adverse event profile, pharmacology, monitoring, and relevant interactions of mannitol, pertinent for interprofessional team members in treating patients with conditions where it is of clinical value., (Copyright © 2022, StatPearls Publishing LLC.)
- Published
- 2022
8. Perioperative Vision Loss
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Weisbrod LJ and Thorell W
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Perioperative vision loss (POVL) is defined as either partial or complete vision loss following a non-ocular surgical procedure. It includes the clinical manifestations of various ophthalmologic conditions. POVL was first reported in 1948 involving a patient with suspected optic globe injury secondary to sustained increased pressure from improper positioning on the headrest. It is a rare but devastating complication typically recognized as the patient is awakening from anesthesia- but may be recognized in the early postoperative period., (Copyright © 2022, StatPearls Publishing LLC.)
- Published
- 2022
9. Tethered Cord Syndrome (TCS)
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Weisbrod LJ and Thorell W
- Abstract
Tethered cord syndrome (TCS) is a well-recognized cause of deterioration in patients with myelomeningocele, with an estimated one-third of patients requiring spinal cord untethering in childhood. Tethered cord syndrome is defined as a stretch-induced clinical constellation arising from tension on the spinal cord due to caudal anchoring to inelastic structures. Inelastic structures restrict vertical movement of the spinal cord and may arise from congenital etiologies, such as myelomeningocele, or acquired etiologies, such as scar formation. Stretch-induced functional changes to spinal cord function may result in neurologic, urologic, musculoskeletal, or gastrointestinal abnormalities. The term "tethered cord syndrome" originates from an article in 1976 authored by Hoffman et al., wherein they describe 31 patients with elongated spinal cords whose symptoms improved following sectioning of the filum terminale., (Copyright © 2022, StatPearls Publishing LLC.)
- Published
- 2022
10. Neuronal Brain Tumors
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Mezzacappa FM and Thorell W
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Neuronal brain tumors are an uncommon group of central nervous system tumors that arise from cells with neuronal differentiation. These tumors may be purely neuronal in origin or have mixed neuronal and glial components, which comprise a subset of glioneuronal tumors.[1] The 2021 World Health Organization (WHO) classification of central nervous system (CNS) tumors includes 14 distinct tumors within this classification. The purely neuronal group includes gangliocytoma, multinodular and vacuolating neuronal tumor (MVNT), dysplastic cerebellar gangliocytoma (Lhermitte-Duclos disease), central neurocytoma, extraventricular neurocytoma, and cerebellar liponeurocytoma. The mixed glioneuronal group includes ganglioglioma, desmoplastic infantile ganglioglioma/desmoplastic infantile astrocytoma (DIG/DIA), dysembryoplastic neuroepithelial tumor (DNET), diffuse glioneuronal tumor with oligodendroglioma-like features and nuclear clusters (DGONC), papillary glioneuronal tumor (PGT), rosette-forming glioneuronal tumor (RGNT), myxoid glioneuronal tumor (MGT), and diffuse leptomeningeal glioneuronal tumor (DLGNT). MVNT, DGONC, and MGT are newly classified entities in the WHO CNS tumor classification schema. Although there are some exceptions, these tumors are mostly low-grade with minimal risk for an aggressive clinical course. They most commonly present with seizures, although other symptoms of space-occupying intracranial lesions such as headache, vomiting, papilledema, cerebellar dysfunction, and focal neurological deficit have also been described.[2][3] Many of these tumors are commonly found in the temporal lobe, which helps explain their predilection for causing seizures.[4] However, these tumors can be found in many locations throughout the supratentorial and infratentorial spaces., (Copyright © 2022, StatPearls Publishing LLC.)
- Published
- 2022
11. Intracranial Hemorrhage
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Tenny S and Thorell W
- Abstract
Intracranial hemorrhage encompasses four broad types of hemorrhage: epidural hemorrhage, subdural hemorrhage, subarachnoid hemorrhage, and intraparenchymal hemorrhage. Each type of hemorrhage is different concerning etiology, findings, prognosis, and outcome. This article provides a broad overview of the types of intracranial hemorrhage., (Copyright © 2022, StatPearls Publishing LLC.)
- Published
- 2022
12. Mega Cisterna Magna
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Weisbrod LJ and Thorell W
- Abstract
The cisterna magna is a cerebrospinal fluid (CSF) filled space located in the posterior fossa dorsal to the medulla and caudal to the cerebellum. Mega cisterna magna refers to a cystic posterior fossa malformation characterized by an enlarged cisterna magna, absence of hydrocephalus, and an intact cerebellar vermis. The concept of mega cisterna magna was first introduced in the 1960s by Gonsette; its size was initially described on ventriculography as above 15 mm in anterior-posterior length, 5 mm height, and 20 mm width. The size has more recently been proposed as a cisterna magna that is greater than 10 mm on mid-sagittal images., (Copyright © 2022, StatPearls Publishing LLC.)
- Published
- 2022
13. Cerebral Salt Wasting Syndrome
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Tenny S and Thorell W
- Abstract
Cerebral salt wasting (CSW) is a potential cause of hyponatremia in the setting of disease of the central nervous system (CNS). Cerebral salt wasting is characterized by hyponatremia with elevated urine sodium and hypovolemia. In the current literature, professionals debate if cerebral salt wasting is a distinct condition or a special form of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). It is important to distinguish between cerebral salt wasting and SIADH as the 2 are treated with opposite treatment strategies. For cerebral salt wasting the patient is given fluids and sodium supplementation. For SIADH the patient is fluid restricted. Cerebral salt wasting tends to resolve within weeks to months after onset but can remain a chronic issue. Leading theories for the pathophysiology of cerebral salt wasting include the release of brain natriuretic peptide (BNP) or damage to the hypothalamus with subsequent disorder sympathetic system., (Copyright © 2022, StatPearls Publishing LLC.)
- Published
- 2022
14. The Effects of Acute Intracranial Pressure Changes on the Episcleral Venous Pressure, Retinal Vein Diameter and Intraocular Pressure in a Pig Model.
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Ghate D, Kedar S, Havens S, Fan S, Thorell W, Nelson C, Gu L, Tong J, and Gulati V
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- Acute Disease, Animals, Biomarkers, Disease Models, Animal, Female, Retinal Vein diagnostic imaging, Sus scrofa, Tomography, Optical Coherence, Tonometry, Ocular, Intracranial Hypertension physiopathology, Intracranial Pressure physiology, Intraocular Pressure physiology, Retinal Vein pathology, Sclera blood supply, Venous Pressure physiology
- Abstract
Purpose: Orbital veins such as the retinal veins and episcleral veins drain into the cavernous sinus, an intracranial venous structure. We studied the effects of acute intracranial pressure (ICP) elevation on episcleral venous pressure, intraocular pressure and retinal vein diameter in an established non-survival pig model., Methods: In six adult female domestic pigs, we increased ICP in 5 mm Hg increments using saline infusion through a lumbar drain. We measured ICP (using parenchymal pressure monitor), intraocular pressure (using pneumatonometer), episcleral venous pressure (using venomanometer), retinal vein diameter (using OCT images) and arterial blood pressure at each stable ICP increment. The average baseline ICP was 5.4 mm Hg (range 1.5-9 mm Hg) and the maximum stable ICP ranged from 18 to 40 mm Hg. Linear mixed models with random intercepts were used to evaluate the effect of acute ICP increase on outcome variables., Results: With acute ICP elevation, we found loss of retinal venous pulsation and increased episcleral venous pressure, intraocular pressure and retinal vein pressure in all animals. Specifically, acute ICP increase was significantly associated with episcleral venous pressure (β = 0.31; 95% CI 0.14-0.48, p < .001), intraocular pressure (β = 0.37, 95%CI 0.24-0.50; p < .001) and retinal vein diameter (β = 11.29, 95%CI 1.57-21.00; p = .03) after controlling for the effects of arterial blood pressure., Conclusion: We believe that the ophthalmic effects of acute ICP elevation are mediated by increased intracranial venous pressure producing upstream pressure changes within the orbital and retinal veins. These results offer exciting possibilities for the development of non-invasive ophthalmic biomarkers to estimate acute ICP elevations following significant neuro-trauma.
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- 2021
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15. Spontaneous Spinal Epidural Hematoma Associated With Apixaban Therapy: A Report of two Cases.
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Mezzacappa FM, Surdell D, and Thorell W
- Abstract
Spontaneous spinal epidural hematoma (SSEH) is a rare clinical entity that can result in severe neurological deficit and warrants emergent neurosurgical evaluation and management. The exact etiology of this entity remains unknown, but certain risk factors exist, including the use of anticoagulant medications. There are few published reports of the association of SSEH with direct factor Xa inhibitors. We aimed to present 2 cases of SSEH in patients on chronic apixaban therapy. To the best of our knowledge, there is only 1 other report of SSEH in the setting of apixaban therapy. A comparison between the cases suggests the importance of rapid recognition and management of SSEH in order to achieve favorable neurological outcomes., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2020, Mezzacappa et al.)
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- 2020
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16. Highly Aggressive and Radiation-Resistant, "Atypical" and Silent Pituitary Corticotrophic Carcinoma: A Case Report and Review of the Literature.
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Flores L, Sleightholm R, Neilsen B, Baine M, Drincic A, Thorell W, Shonka N, Oupicky D, and Zhang C
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Background: Pituitary tumors typically remain silent unless interaction with nearby structures occurs. Rare subsets of pituitary tumors display aggressive phenotypes: highly mitotic, locally invasive, metastatic, chemotherapy and radiation resistant, etc. Disease progression and response to therapy is ill-defined in these subtypes, and their true prognostic potential is debated. Thus, identifying tumor characteristics with prognostic value and efficacious treatment options remains a challenge in aggressive pituitary tumors., Case Presentation: A 45-year-old female presented with a nonfunctioning corticotropic pituitary macroadenoma with biomarkers suggestive of an "atypical" subtype: Ki-67 of 8-12%, increased mitosis, and locally invasive. Despite resections and radiation, growth continued, eventually affecting her vision. Although histologically ACTH positive, the patient remained clinically asymptomatic. Twelve months later, an episode of Cushing's disease-induced psychosis prompted a PET-CT scan, identifying sites of metastasis. Temozolomide was added to her medical regimen, and her metastatic liver lesions and boney metastases were treated with radiofrequency ablation and stereotactic body radiation therapy, respectively. Systemic treatment resulted in a drop in her ACTH levels, with her most recent scans/labs at 12 months following RFA suggesting remission., Conclusions: This is a unique presentation of a pituitary tumor, displaying characteristics of both clinically silent corticotropic and "atypical" macroadenoma subtypes. Although initially ACTH positive while clinically silent, the patient's disease ultimately recurred metastatically with manifestations of Cushing's disease and psychosis. With the addition of temozolomide to her treatment plan, her primary and metastatic sites have responded favorably to radiation therapy. Thus, the addition of temozolomide may be beneficial in the treatment of aggressive pituitary tumors.
- Published
- 2019
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17. Measuring Hemodynamic Changes in the Ophthalmic Artery During Applied Force for Noninvasive Intracranial Pressure Monitoring: Test Results in a Porcine Model.
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Twedt M, Pfeifer C, Thorell W, and Bashford G
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- Animals, Female, Swine physiology, Ultrasonography, Doppler, Transcranial methods, Hemodynamics physiology, Intracranial Pressure, Monitoring, Physiologic methods, Ophthalmic Artery physiopathology, Ultrasonography, Doppler, Transcranial standards
- Abstract
Possible traumatic brain injury victims would greatly benefit from a handheld, noninvasive intracranial pressure (ICP) monitoring tool, which a medic could operate in a remote area. Such a device would also benefit the transport of injured soldiers during en route medical care and critical care air transport. This study demonstrates the use of noninvasive blood flow measurements in the eye by ultrasound as a proxy for ICP. ICP was artificially raised in a porcine model and resultant blood flow change in the ophthalmic artery was measured. In addition, the ultrasound transducer itself was used to compress the eye further altering ophthalmic hemodynamics. Blood flow velocities at a range of applied forces and ICP were compared. It was found that 3.25 N of force applied to the cornea was sufficient to produce significant changes in ophthalmic artery blood dynamics regardless of the ICP value. Specifically, the change in resistivity index (RI) and pulsatility index (PI) as force was applied to the cornea correlated with ICP levels. In multiple animal experiments, the magnitude of PI/RI percent change was inversely related to differences in ICP. Force applied to the cornea at baseline ICP resulted in a 15% increase in PI/RI. Results indicate that as ICP increases, the percent change in PI/RI while force is applied decreases. The consistency of data collected indicates that a trend line developed with this data and from similar experiments could be used as a predictive measurement of ICP., (Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.)
- Published
- 2017
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18. Remote cerebellar hemorrhage following supratentorial cerebrovascular surgery.
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Smith R, Kebriaei M, Gard A, Thorell W, and Surdell D
- Subjects
- Adult, Brain diagnostic imaging, Cerebellar Diseases diagnostic imaging, Humans, Intracranial Aneurysm surgery, Intracranial Arteriovenous Malformations surgery, Intracranial Hemorrhages diagnostic imaging, Male, Middle Aged, Postoperative Hemorrhage diagnostic imaging, Tomography, X-Ray Computed, Cerebellar Diseases etiology, Intracranial Hemorrhages etiology, Neurosurgical Procedures adverse effects, Postoperative Hemorrhage etiology
- Abstract
Three patients with remote cerebellar hemorrhage following supratentorial cerebrovascular surgery are presented. Remote cerebellar hemorrhage is a rare surgical complication that is most often associated with aneurysm clipping or temporal lobectomies. Bleeding occurs on the superior cerebellar cortex and is believed to be venous in origin. The precise pathogenesis of remote cerebellar hemorrhage has yet to be fully elucidated but is generally considered to be a consequence of intraoperative cerebrospinal fluid loss causing caudal displacement of the cerebellum with resultant stretching of the supracerebellar veins. This case series will hopefully shed further light on the incidence, presentation, workup, and treatment of this particular complication of supratentorial surgery., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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19. Angiogram-negative subarachnoid hemorrhage: outcomes data and review of the literature.
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Boswell S, Thorell W, Gogela S, Lyden E, and Surdell D
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- Brain Ischemia etiology, Disease Progression, Female, Headache etiology, Humans, Hydrocephalus etiology, Male, Middle Aged, Odds Ratio, Predictive Value of Tests, Prognosis, Recurrence, Retrospective Studies, Risk Factors, Subarachnoid Hemorrhage complications, Time Factors, Vasospasm, Intracranial etiology, Cerebral Angiography, Subarachnoid Hemorrhage diagnostic imaging
- Abstract
Spontaneous subarachnoid hemorrhage (SAH) is most commonly caused by rupture of a saccular aneurysm or other structural pathologies. Occasionally, no structural cause for the hemorrhage can be identified by radiographic imaging. These hemorrhages, termed angiogram-negative SAH, are generally considered to have a better prognosis than aneurysmal SAH. Angiogram-negative SAH subgroups include benign perimesencephalic SAH (PMH) and aneurysmal-type SAH. Outcome data for these subgroups differ from those for the group as a whole. We report data for 31 patients who presented to our institution from 2006 to the present. We performed a retrospective chart review, and report outcome data that include rates of rehemorrhage, hydrocephalus, vasospasm, permanent ischemic deficits, headaches, and outcomes based on modified Rankin Scale scores. We also performed a review of the literature and meta-analysis of the data therein. We compared rates of complications in the PMH subgroup and the diffuse-type hemorrhage subgroup. The chart review revealed no poor outcomes and no rehemorrhages in the patients with PMH. In the diffuse hemorrhage subgroup, 1 patient had a rehemorrhage and 2 patients had a poor outcome. Our literature review found an OR of 6.23 for a good outcome for PMH versus diffuse-type hemorrhage, and an OR of 2.78 for rehemorrhage in PMH versus diffuse-type hemorrhage. Angiogram-negative SAH is not a benign entity. Complications are present but are significantly reduced, and outcomes are improved, compared with aneurysmal SAH., (Copyright © 2013 National Stroke Association. All rights reserved.)
- Published
- 2013
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20. Balloon-assisted microvascular clipping of paraclinoid aneurysms. Technical note.
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Thorell W, Rasmussen P, Perl J, Masaryk T, and Mayberg M
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- Aged, Carotid Artery, Internal pathology, Female, Humans, Intracranial Embolism and Thrombosis prevention & control, Male, Middle Aged, Treatment Outcome, Angioplasty, Balloon methods, Embolization, Therapeutic methods, Intracranial Aneurysm surgery, Surgical Instruments, Vascular Surgical Procedures methods
- Abstract
Paraclinoid aneurysms represent a significant surgical challenge. Multiple techniques have been developed to maximize the effectiveness and safety of excluding these aneurysms from the cerebral circulation. Endovascular balloons have been used for proximal control of parent arteries during the treatment of aneurysms. In this report the authors describe the technique of navigating an endovascular balloon across the neck of paraclinoid aneurysms in four patients to gain proximal control, improve the accuracy of clip placement, and reduce the risk of distal embolization of intraluminal thrombus. Six consecutive patients with giant or complex aneurysms of the ophthalmic or paraclinoid internal carotid artery that were not amenable to endovascular obliteration were retrospectively analyzed. In all six patients, the aneurysm was exposed and dissected for microsurgical clipping, and attempts were made to navigate a nondetachable, compliant silicone balloon across the neck of the aneurysm. If successfully placed, the balloon was inflated during clip placement. In four patients, the balloon was successfully navigated across the neck of the aneurysm and was inflated during clip application. Internal carotid artery tortuosity precluded navigation of the balloon into the intracranial circulation in two patients. All aneurysms were completely excluded from the parent vessel according to postoperative angiography studies. No complication occurred as a direct result of the endovascular portion of the procedure. Endovascular balloon stenting of complex paraclinoid aneurysms during microvascular clipping may provide an adjunctive therapy that facilitates safe and accurate clip placement.
- Published
- 2004
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21. Role of RyRs and IP3 receptors after traumatic injury to spinal cord white matter.
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Thorell WE, Leibrock LG, and Agrawal SK
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- Action Potentials drug effects, Animals, Boron Compounds pharmacology, Caffeine pharmacology, Calcium-Binding Proteins agonists, Calcium-Binding Proteins antagonists & inhibitors, Central Nervous System Stimulants pharmacology, Chelating Agents pharmacology, Dantrolene pharmacology, Egtazic Acid pharmacology, Electrophysiology, In Vitro Techniques, Inositol 1,4,5-Trisphosphate Receptors, Male, Models, Animal, Muscle Relaxants, Central pharmacology, Neural Conduction drug effects, Rats, Rats, Wistar, Receptors, Cytoplasmic and Nuclear agonists, Receptors, Cytoplasmic and Nuclear antagonists & inhibitors, Ryanodine agonists, Ryanodine antagonists & inhibitors, Ryanodine pharmacology, Calcium physiology, Calcium Channels physiology, Calcium-Binding Proteins physiology, Egtazic Acid analogs & derivatives, Receptors, Cytoplasmic and Nuclear physiology, Ryanodine Receptor Calcium Release Channel physiology, Spinal Cord Injuries metabolism, Spinal Cord Injuries physiopathology
- Abstract
Calcium influx and elevation of intracellular free calcium (Ca2+i), with subsequent activation of degenerative enzymes is hypothesized to cause cell injury and death after trauma. We examined the effects of traumatic compressive injury on (Ca2+)i dynamics in spinal cord white matter. We conducted electrophysiological studies with ryanodine and inositol (1,4,5)-triphosphate (IP3) receptor agonists and antagonists in an in vitro model of spinal cord injury (SCI). A 25-30-mm length of dorsal column was isolated from the spinal cord of adult rats, pinned in an in vitro recording chamber (37 degrees C) and injured with a modified clip (2-g closing force) for 15 sec. The functional integrity of the dorsal column was monitored electrophysiologically by quantitatively measuring the compound action potential (CAP) with glass microelectrodes. The CAP decreased to 55.2+/-6.8% of control (p < 0.05) after spinal cord injury (SCI). Chelation of Ca2+i with BAPTA-AM (a high-affinity calcium chelator) promoted significantly greater recovery of CAP amplitude (83.2+/-4.2% of control; p < 0.05) after injury. Infusion of caffeine (1 and 10 mM) exacerbated CAP amplitude decline (45.1+/-5.9% of control; p < 0.05; 44.6+/-3.1% of control; p < 0.05) postinjury. Blockade of Ca2+i release through ryanodine-sensitive receptors (RyRs) with dantrolene (10 microM) and ryanodine (50 microM), conferred significant (p < 0.05) improvement in CAP amplitude after injury. On the other hand, blockade of Ca2+i with inositol (1,4,5)-triphosphate receptor (IP3Rs) blocker 2APB (10 microM) also conferred significant improvement in CAP amplitude after injury (82.9+/-7.9%; p < 0.05). In conclusion, the injurious effects of Ca2+i in traumatic central nervous system (CNS) white matter injury appear to be mediated both by RyRs and through IP3Rs calcium-induced calcium release receptors (CICRs).
- Published
- 2002
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22. Patient outcome after resection of lumbar juxtafacet cysts.
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Banning CS, Thorell WE, and Leibrock LG
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- Adult, Aged, Aged, 80 and over, Female, Follow-Up Studies, Humans, Lumbar Vertebrae surgery, Magnetic Resonance Imaging, Male, Middle Aged, Radiculopathy etiology, Recurrence, Retrospective Studies, Surveys and Questionnaires, Synovial Cyst complications, Synovial Cyst pathology, Treatment Outcome, Lumbar Vertebrae pathology, Radiculopathy surgery, Synovial Cyst surgery
- Abstract
Study Design: Retrospective review of patients who underwent lumbar juxtafacet cyst resection with questionnaire follow-up., Objectives: Determine the long-term outcome after resection of lumbar juxtafacet cysts., Summary of Background Data: Juxtafacet cysts are uncommon causes of radicular pain and are often associated with significant spinal degenerative disease. Previous studies have not focused on the outcome of patients who have undergone resection., Methods: Charts of 29 patients who underwent lumbar juxtafacet resection were reviewed and an outcomes questionnaire was sent to each., Results: Thirty-three lumbar juxtafacet cysts were resected from 29 patients. Cysts, 31 (94%) from facets and 2 (6%) from the ligamentum flavum, most commonly arose at the L4-L5 level (51%). Twelve patients (41%) were found to have some degree of spondylolisthesis before surgery, while 26 patients (90%) had facet arthropathy. Two patients (7%) underwent concurrent resection and fusion. Recurrence occurred in 3%. Three patients (9%) had subsequent lumbar spine operations, including 2 fusions (6%). Incidental durotomy was the most common surgical complication occurring in 3 cases (9%). Twenty-four patients (83%) responded to follow-up questionnaire or phone interview. Mean length of follow-up was 24 months (4-64 months). Twenty patients (83%) reported improvement in pain, and 16 (67%) reported an improved level of function. All respondents reported some degree of improvement in their condition after surgery., Conclusions: Juxtafacet cysts are an uncommon cause of radiculopathy. Surgical resection is the treatment of choice with low rates of complications, recurrences, and residual complaints.
- Published
- 2001
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23. History of neurosurgical techniques in head injury.
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Thorell W and Aarabi B
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- Brain Injuries surgery, History, 16th Century, History, 17th Century, History, 18th Century, History, 19th Century, History, 20th Century, History, Ancient, History, Medieval, Humans, Military Medicine history, Trephining history, Brain Injuries history, Neurosurgical Procedures history
- Abstract
The techniques of surgery for head injury have evolved from an emphasis on exploration for diagnosis to a focus on decompression, maintenance of adequate perfusion, restoration of anatomic integrity, prevention of complications, and preservation of cosmesis.
- Published
- 2001
24. Giant cell reparative granuloma of the petrous temporal bone: a case report and literature review.
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Williams JC, Thorell WE, Treves JS, Fidler ME, Moore GF, and Leibrock LG
- Abstract
Giant cell reparative granuloma (GCRG) is an unusual, benign bone lesion that most commonly affects the maxilla and mandible; skull involvement is rare. The etiology is uncertain but may be related to trauma. GCRG is difficult to distinguish from giant cell tumor of the bone and has a lower recurrence rate. Thirteen reports of temporal bone GCRG in 11 patients have been reported. One report of a petrous GCRG in a 3-year-old girl has been identified. A 38-year-old male presented with a 2-year history of fullness in his left ear, ipsilateral hearing loss, and intermittent cacosmia. Computed tomography and magnetic resonance imaging revealed a large left-sided anterior temporal extradural mass. The patient underwent a left frontotemporal craniotomy and resection of a left temporal fossa tumor that involved the petrous and squamous parts of the temporal bone. The patient's post-operative course was uneventful, except for increased hearing loss secondary to opening of the epitympanum. Follow-up at one month revealed no other problems. Histopathology of the specimen was consistent with a giant cell reparative granuloma.
- Published
- 2000
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25. The long-term clinical outcome of patients undergoing anterior cervical discectomy with and without intervertebral bone graft placement.
- Author
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Thorell W, Cooper J, Hellbusch L, and Leibrock L
- Subjects
- Adult, Aged, Female, Follow-Up Studies, Humans, Male, Middle Aged, Neurologic Examination, Outcome and Process Assessment, Health Care, Bone Transplantation, Cervical Vertebrae surgery, Diskectomy, Intervertebral Disc Displacement surgery, Postoperative Complications diagnosis
- Abstract
Objective: This retrospective study provides data on the long-term clinical outcomes of patients with either anterior cervical discectomy alone (ACD) or anterior cervical discectomy with intervertebral bone graft placement (ACDF)., Methods: A questionnaire was mailed to 525 patients who had undergone ACD (290 patients) or ACDF (235 patients) at least 2 years previously. All procedures were performed by University of Nebraska Medical Center faculty in the Section of Neurosurgery. The follow-up period averaged 8.1 years, with a range of 2 to 14 years., Results: Two hundred sixty-two (49.9%) patients responded to the questionnaire. There was no demographic difference between respondents and nonrespondents (P > 0.05). Respondents who underwent ACDF reported fewer problems with pain than did those who underwent ACD (P < 0.05). A higher percentage of respondents with ACDF reported that they had normal function than did those who underwent ACD (P < 0.05). When limited to respondents who underwent first-time, single-level operations (191 patients), similar results were obtained for the pain parameter (P < 0.05) but not for the level of function (P = 0.25). Patients with longer follow-up periods had fewer problems with pain and better levels of function (P < 0.05)., Conclusion: Patients who underwent ACD or ACDF did well and benefited from their operations. Those who underwent ACDF did better than those who underwent ACD. Length of follow-up was also an important predictor of current levels of function and pain.
- Published
- 1998
- Full Text
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