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Dive into the research topics where Harry R. van Loveren is active.

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Featured researches published by Harry R. van Loveren.


Stroke | 1999

Early Surgical Treatment for Supratentorial Intracerebral Hemorrhage A Randomized Feasibility Study

Mario Zuccarello; Thomas G. Brott; Laurent Derex; Rashmi Kothari; John M. Tew; Harry R. van Loveren; Hwa Shain Yeh; Thomas A. Tomsick; Arthur Pancioli; Jane Khoury; Joseph P. Broderick

BACKGROUND AND PURPOSE The safety and the effectiveness of the surgical treatment of spontaneous intracerebral hemorrhage (ICH) remain controversial. To investigate the feasibility of urgent surgical evacuation of ICH, we conducted a small, randomized feasibility study of early surgical treatment versus current nonoperative management in patients with spontaneous supratentorial ICH. METHODS Patients with spontaneous supratentorial ICH who presented to 1 university and 2 community hospitals were randomized to surgical treatment or best medical treatment. Principal eligibility criteria were ICH volume >10 cm(3) on baseline CT scan with a focal neurological deficit, Glasgow Coma Scale score >4 at the time of enrollment, randomization and therapy within 24 hours of symptom onset, surgery within 3 hours of randomization, and no evidence for ruptured aneurysm or arteriovenous malformation. The primary end point was the 3-month Glasgow Outcome Scale (GOS). A good outcome was defined as a 3-month GOS score >3. RESULTS Twenty patients were randomized over 24 months, 9 to surgical intervention and 11 to medical treatment. The median time from onset of symptoms to presentation at the treating hospitals was 3 hours and 17 minutes, the time from randomization to surgery was 1 hour and 20 minutes, and the time from onset of symptoms to surgery was 8 hours and 35 minutes. The likelihood of a good outcome (primary outcome measure: GOS score >3) for the surgical treatment group (56%) did not differ significantly from the medical treatment group (36%). There was no significant difference in mortality at 3 months. Analysis of the secondary 3-month outcome measures showed a nonsignificant trend toward a better outcome in the surgical treatment group versus the medical treatment group for the median GOS, Barthel Index, and Rankin Scale and a significant difference in the National Institutes of Health Stroke Scale score (4 versus 14; P=0.04). CONCLUSIONS Very early surgical treatment for acute ICH is difficult to achieve but feasible at academic medical centers and community hospitals. The trend toward less 3-month morbidity with surgical intervention in patients with spontaneous supratentorial ICH warrants further investigation of very early clot removal in larger randomized clinical trials.


Neurosurgery | 2001

Intraoperative Magnetic Resonance Imaging to Determine the Extent of Resection of Pituitary Macroadenomas during Transsphenoidal Microsurgery

Robert J. Bohinski; Ronald E. Warnick; Mary F. Gaskill-Shipley; Mario Zuccarello; Harry R. van Loveren; Donald W. Kormos; John M. Tew

OBJECTIVEWell-established surgical goals for pituitary macroadenomas include gross total resection for noninvasive tumors and debulking with optic chiasm decompression for invasive tumors. In this report, we examine the safety, reliability, and outcome of intraoperative magnetic resonance imaging (iMRI) used to assess the extent of resection, and thus the achievement of preoperative surgical goals, during transsphenoidal microneurosurgery. METHODSOur magnetic resonance operating room contains a Hitachi AIRIS II 0.3-T, vertical-field open magnet (Hitachi Medical Systems America, Inc., Twinsburg, OH). A motorized scanner tabletop moves the patient between the imaging and operative positions. For transsphenoidal surgery, the patient is positioned directly on the scanner tabletop so that the surgical field is located between 1.2 and 1.6 m from the magnet isocenter. At this location, the magnetic field strength is low (<20 G), thus permitting the use of many conventional surgical instruments. Thirty consecutive patients with pituitary macroadenomas underwent tumor resection in our magnetic resonance operating room by use of a standard transsphenoidal approach. After initial resection, the patient was advanced into the scanner for imaging. If residual tumor was demonstrated and deemed surgically accessible, the patient underwent immediate re-exploration. RESULTSiMRI was performed successfully in all 30 patients. In one patient, iMRI was used to clarify the significance of hemorrhage from the sellar region and resulted in immediate conversion of the procedure to a craniotomy. In the remaining 29 patients, initial iMRI demonstrated that the endpoint for extent of resection had been achieved in only 10 patients (34%) after an initial resection attempt, whereas 19 patients (66%) still had unacceptable residual tumor. All 19 of these latter patients underwent re-exploration. Ultimately, re-exploration resulted in the achievement of the planned endpoint for extent of resection in all of the 29 completed transsphenoidal explorations. Operative time was extended in all cases by at least 20 minutes. CONCLUSIONiMRI can be used to safely, reliably, and objectively assess the extent of resection of pituitary macroadenomas during the transsphenoidal approach. The surgeon is frequently surprised by the extent of residual tumor after an initial resection attempt and finds the intraoperative images useful for guiding further resection.


Neurosurgery | 1995

Treatment of aneurysms of the internal carotid artery by intravascular balloon occlusion: long-term follow-up of 58 patients.

Jeffrey J. Larson; John M. Tew; Thomas A. Tomsick; Harry R. van Loveren

ABSTRACT: LONG‐TERM EVALUATION OF patients with aneurysms of the internal carotid artery (ICA) treated by intravascular balloon occlusion has not been reported. From 1977 to 1992, 58 patients (age 14 to 81 years) with ICA aneurysms were treated at our institution by this technique. The aneurysms included 40 intracavernous carotid, 5 petrous carotid, 3 cervical carotid, and 10 ophthalmic segment aneurysms. Presenting symptoms were caused by mass effect in 45 patients, transient ischemia or cerebral infarction as a result of emboli in 6, subarachnoid hemorrhage in 4, and epistaxis in 3. Preoperative temporary balloon occlusion of the ICA combined with cerebral blood flow monitoring and induced hypotension were used to determine tolerance for occlusion. Two patients not tolerating test occlusion required an extracranial‐intracranial bypass procedure, and another patient underwent extracranial‐intracranial bypass prior to test occlusion because of contralateral ICA stenosis. In 55 patients, aneurysms were excluded from the circulation by either occluding the proximal ICA or trapping the aneurysm neck. In three patients, the aneurysm was directly obliterated with intravascular balloons with preservation of the parent ICA. Three patients died during treatment, one from subarachnoid hemorrhage and two from cerebral infarction. Mean follow‐up was 76 months (range, 6 months to 15 years). Six patients who developed transient ischemia caused by emboli responded to volume expansion and anticoagulation treatment. Two patients developed a delayed infarction, and one patient developed aneurysm enlargement that required surgical clipping and obliteration. Two patients suffered a delayed subarachnoid hemorrhage, one from a de novo aneurysm arising from the anterior communicating artery and another from a contralateral A1‐A2 junction aneurysm that had enlarged after treatment for the ICA aneurysm. In long‐term follow‐up, intravascular balloon occlusion was a relatively safe, effective treatment for eliminating ICA aneurysms that posed low risk for early or delayed ischemia or infarction. Intravascular balloon occlusion is the treatment of choice for extradural aneurysms and some distal carotid aneurysms.


Neurosurgery | 1999

Colored silicone injection for use in neurosurgical dissections: anatomic technical note.

Abhay Sanan; Khaled Aziz; Rashid M. Janjua; Harry R. van Loveren; Jeffrey T. Keller

OBJECTIVE The dissection of cadaveric specimens is very important for a more sophisticated understanding of neurosurgical anatomic features and approaches. Teaching known approaches to residents or learning new approaches is best performed in a cadaveric laboratory. The utility of neurosurgical cadaveric dissections can be improved by injecting the intracranial vascular tree with colored silicone. The vascular anatomic features, which are integral to neurosurgical procedures, are much more clearly defined in injected specimens. METHODS Self-curing colored silicone rubber is used to inject the arteries and veins (red and blue, respectively) of the head. This process is described in a step-by-step format. Six steps are required and can be summarized as follows: 1) exposure of the great vessels, 2) cannulation of the great vessels, 3) irrigation of the head, 4) preparation of the colored silicone, 5) injection of the colored silicone, and 6) evaluation of the final specimen. CONCLUSION Injection of colored silicone into the vascular tree can enhance the educational value of cadaveric head dissections. This report describes the technique of vascular injection that is used in the Goodyear Microsurgical Laboratory, the University of Cincinnati, and the Mayfield Clinic.


Neurosurgery | 2004

Large sphenoid wing meningiomas involving the cavernous sinus: Conservative surgical strategies for better functional outcomes

Khaled Aziz; S. Froelich; Elias Dagnew; Walter Jean; John C. Breneman; Mario Zuccarello; Harry R. van Loveren; John M. Tew; Roberto Delfini; Laligam N. Sekhar; L. Dade Lunsford

OBJECTIVE:The ability to resect meningiomas that involve the medial and anterior compartments of the cavernous sinus has been refuted. In this retrospective study, we determined the efficacy of total resection of meningiomas that invade the cavernous sinus but are restricted to the lateral compartment. METHODS:We reviewed the charts of 38 consecutive patients with sphenocavernous, clinoidocavernous, and sphenoclinoidocavernous meningiomas who underwent surgical treatment. We assessed early and late cranial nerve morbidity, extent of resection, and long-term outcome (mean, 96 mo). RESULTS:In all patients, tumors exceeded 3 cm diameter. In 22 of 24 patients, total microscopic excision was achieved in tumors that involved only the lateral compartment of the cavernous sinus and touched or partially encased the cavernous internal carotid artery (i.e., modified Hirsch Grades 0 and 1, respectively). In 2 of 24 patients, remaining tumor infiltrated the superior orbital fissure. All 14 patients who had tumors that encased (with or without narrowing) the cavernous segment of the internal carotid artery (Hirsch Grades 2–4) underwent incomplete resection. Among 38 patients, mortality was 0%, late cranial nerve deficits remained in 6 (16%), and late Karnofsky Performance Scale scores exceeded 90 in 34 patients (90%). Four patients (10.5%) developed a recurrence or regrowth. Of 20 patients who were treated with either linear accelerator-based stereotactic radiosurgery or fractionated conformal radiotherapy, 11 had residual tumor and a moderate to high proliferative index, 4 had atypical tumors and 1 had angioblastic meningioma after total excision, 2 had regrowth, and 2 had recurrent tumors. In 18 (90%) of the 20 patients who underwent radiation, tumor size was reduced or controlled. CONCLUSION:On the basis of this study and a review of the literature, we demonstrate that sphenocavernous, clinoidocavernous, and sphenoclinoidocavernous meningiomas of Hirsch Grades 0 and 1 can be excised from the lateral compartment of the cavernous sinus without postoperative mortality and with acceptable rates of morbidity. Residual tumor in the medial compartment (Hirsch Grades 2–4) may be treated with some form of radiation therapy or observation.


Neurosurgery | 2000

Microsurgical Anatomic Features and Nomenclature of the Paraclinoid Region

Jae Min Kim; Alberto Romano; Abhay Sanan; Harry R. van Loveren; Jeffrey T. Keller

OBJECTIVE We describe the detailed microsurgical anatomic features of the clinoid (C5) segment of the internal carotid artery (ICA) and surrounding structures, clarify the anatomic relationships of structures in this region, and emphasize the clinical relevance of these observations. Furthermore, because the nomenclature of the paraclinoid region is confusing and lacks standardization, this report provides a glossary of terms that are commonly used to descibe the anatomic features of the paraclinoid region. METHODS The region surrounding the anterior clinoid process was observed in 70 specimens from 35 formalin-fixed cadaveric heads. Detailed microanatomic dissections were performed in 10 specimens. Histological sections of this region were obtained from the formalin-fixed cadaveric specimens. RESULTS The clinoid segment of the ICA is the portion that abuts the clinoid process. This portion of the ICA can be directly observed only after removal of the clinoid process. The dura of the cavernous sinus roof separates to enclose the clinoid process. The clinoid segment of the ICA exists only where this separation of dural layers is present. Because the clinoid process does not completely enclose the ICA in most cases, the clinoid segment is shaped more like a wedge than a cylinder. The outer layer of the dura (dura propria) is a thick membrane that fuses with the adventitia of the ICA to form a competent ring that separates the intradural ICA from the extradural ICA. The thin inner membranous layer of the dura loosely surrounds the ICA throughout the entire length of its clinoid segment. The most proximal aspect of this membrane defines the proximal dural ring. The proximal ring is incompetent and admits a variable number of veins from the cavernous plexus that accompany the ICA throughout its clinoid segment. CONCLUSION The narrow space between the inner dural layer and the clinoid ICA is continuous with the cavernous sinus via an incompetent proximal dural ring. This space between the clinoid ICA and the inner dural layer contains a variable number of veins that directly communicate with the cavernous plexus. Given the inconstancy of the venous plexus surrounding the clinoid ICA, we think that categorical labeling of the clinoid ICA as intracavernous or extracavernous cannot be justified.


Brain Research | 2009

Severity of controlled cortical impact traumatic brain injury in rats and mice dictates degree of behavioral deficits

SeongJin Yu; Yuji Kaneko; Eunkyung Cate Bae; Christine E. Stahl; Yun Wang; Harry R. van Loveren; Paul R. Sanberg; Cesar V. Borlongan

The clinical presentation of traumatic brain injury (TBI) involves either mild, moderate, or severe injury to the head resulting in long-term and even permanent disability. The recapitulation of this clinical scenario in animal models should allow examination of the pathophysiology of the trauma and its treatment. To date, only a few studies have demonstrated TBI animal models encompassing the three levels of trauma severity. Thus, in the present study we characterized in mice and rats both brain histopathologic and behavioral alterations across a range of injury magnitudes arising from mild, moderate, and severe TBI produced by controlled cortical impact injury technique. Here, we replicated the previously observed TBI severity-dependent brain damage as revealed by 2,3,5-triphenyltetrazolium chloride staining (severe > moderate > mild) in rats, but also extended this pattern of histopathologic changes in mice. Moreover, we showed severity-dependent abnormalities in locomotor and cognitive behaviors in TBI-exposed rats and mice. Taken together, these results support the use of rodent models of TBI as a sensitive platform for investigations of the injury-induced neurostructural and behavioral deficits, which should serve as key outcome parameters for testing experimental therapeutics.


Neurosurgery | 2002

Facial nerve neuromas: report of 10 cases and review of the literature.

Jonathan D. Sherman; Elias Dagnew; Myles L. Pensak; Harry R. van Loveren; John M. Tew

OBJECTIVE This study reviewed the management and outcomes of facial neuromas during the past decade at our institution. The goal was to analyze differences in presentation on the basis of location of the facial neuroma, review facial nerve function and hearing preservation postoperatively, and understand the characteristics of patients with tumors limited to the cerebellopontine angle or internal auditory canal. We also report an unusual case of a facial neuroma limited to the nervus intermedius. METHODS Nine patients with facial neuromas and one with Jacobson’s nerve neuroma underwent surgery, and total resection was accomplished in nine patients. A chart review for pre- and postoperative data was performed, after which all patients were evaluated on an outpatient basis. RESULTS The mean age of the patients was 47 years; mean follow-up time was 33.1 months. The most common presenting symptoms were hearing loss (six patients) and facial paresis (five patients). A total of five patients had progressive (four patients) or recurrent (one patient) facial paresis. No patient experienced worsened hearing as a result of surgery, and one experienced improvement in a conductive hearing deficit. Five patients required cable graft repair of the facial nerve; four improved to House-Brackmann Grade 3 facial paresis. Four of five patients with preserved anatomic continuity of the facial nerve regained normal facial function. There were no surgical complications. No tumors have recurred during follow-up. We report the second nerve sheath tumor limited to the nervus intermedius. CONCLUSION This series documents that facial neuromas can be resected safely with preservation of facial nerve and hearing function. Preservation of anatomic continuity of the facial nerve should be attempted, and it does not seem to lead to frequent recurrence. Tumors limited to the cerebellopontine angle/internal auditory canal are a unique subset of facial neuromas with characteristics that vary greatly from facial neuromas in other locations, and they are indistinguishable clinically from acoustic neuromas.


Neurosurgical Focus | 2009

Surgical management of moyamoya disease: a review.

Ali A. Baaj; Siviero Agazzi; Zafar A. Sayed; Maria Toledo; Robert F. Spetzler; Harry R. van Loveren

Moyamoya disease (MMD) is a progressive, occlusive disease of the distal internal carotid arteries associated with secondary stenosis of the circle of Willis. Symptoms include ischemic infarcts in children and hemorrhages in adults. Bypass of the stenotic vessel(s) is the primary surgical treatment modality for MMD. Superficial temporal artery-to-middle cerebral artery bypass is the most common direct bypass method. Indirect techniques rely on the approximation of vascularized tissue to the cerebral cortex to promote neoangiogenesis. This tissue may be in the form of muscle, pericranium, dura, or even omentum. This review highlights the surgical options available for the treatment of MMD.


Neuropeptides | 2011

Cyclosporine-A as a neuroprotective agent against stroke: its translation from laboratory research to clinical application.

Mohamed M. Osman; Dzenan Lulic; Loren E. Glover; Christine E. Stahl; Tsz Lau; Harry R. van Loveren; Cesar V. Borlongan

Stoke remains a leading cause of death and disability with limited treatment options. Extensive research has been aimed at studying cell death events that accompany stroke and how to use these same cell death pathways as potential therapeutic targets for treating the disease. The mitochondrial permeability transition pore (MPTP) has been implicated as a major factor associated with stroke-induced neuronal cell death. MPTP activation and increased permeability has been shown to contribute to the events that lead to cell death. Cyclosporine A (CsA), a widely used immunosuppressant in transplantation and rheumatic medicine, has been recently shown to possess neuroprotective properties through its ability to block the MPTP, which in turn inhibits neuronal damage. This newfound CsA-mediated neuroprotection pathway prompted research on its use to prevent cell death in stroke and other neurological conditions. Preclinical studies are being conducted in hopes of establishing the safety and efficacy guidelines for CsA use in human trials as a potential neuroprotective agent against stroke. In this review, we provide an overview of the current laboratory and clinical status of CsA neuroprotection.

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Siviero Agazzi

University of South Florida

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John M. Tew

University of Cincinnati

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A. Samy Youssef

University of South Florida

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Khaled Aziz

University of Cincinnati

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Yuji Kaneko

University of South Florida

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Naoki Tajiri

University of South Florida

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Cesar V. Borlongan

University of South Florida

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