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Dive into the research topics where William F. Chandler is active.

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Featured researches published by William F. Chandler.


Neurosurgery | 2004

Intraventricular thrombolysis speeds blood clot resolution: Results of a pilot, prospective, randomized, double-blind, controlled trial

Neal Naff; Daniel F. Hanley; Penelope M. Keyl; Stanley Tuhrim; Michael A. Kraut; Joshua B. Bederson; Ross Bullock; Stephan A. Mayer; Eric Schmutzhard; Warren R. Selman; William F. Chandler; Hugh J. L. Garton; Christopher J. Chittum; Stephen J. Haines; J. Max Findlay; Robert G. Grossman

OBJECTIVEAnimal models and clinical studies suggest that intraventricular thrombolysis improves clot resolution and clinical outcomes among patients with intraventricular hemorrhage. However, this intervention may increase the rates of rebleeding and infection. To assess the safety and efficacy of intraventricular thrombolysis, we conducted a pilot, randomized, double-blind, controlled, multicenter study. METHODSPatients with intraventricular hemorrhage requiring ventriculostomy were randomized to receive intraventricular injections of normal saline solution or urokinase (25,000 international units) at 12-hour intervals. Injections continued until ventricular drainage was discontinued according to prespecified clinical criteria. Head computed tomographic scans were obtained daily, for quantitative determinations of intraventricular hemorrhage volumes. The rate of clot resolution was estimated for each group. RESULTSTwelve subjects were enrolled (urokinase, seven patients; placebo, five patients). Commercial withdrawal of urokinase precluded additional enrollment. The urokinase and placebo groups were similar with respect to age (49.6 versus 55.2 yr, P = 0.43) and presenting Glasgow Coma Scale scores (7.14 versus 8.00, P = 0.72). Randomization to the urokinase treatment arm (P = 0.02) and female sex (P = 0.008) favorably affected the clot resolution rate. The sex-adjusted clot half-life for the urokinase-treated group was reduced 44.6%, compared with the value for the placebo group (4.69 versus 8.48 d). CONCLUSIONIntraventricular thrombolysis with urokinase speeds the resolution of intraventricular blood clots, compared with treatment with ventricular drainage alone.


Neurosurgery | 2004

The role of radiation therapy after surgical resection of nonfunctional pituitary macroadenomas.

Paul Park; William F. Chandler; Ariel L. Barkan; John J. Orrego; John A. Cowan; Kent A. Griffith; Christina Tsien

OBJECTIVE:Radiotherapy after aggressive surgical resection of nonfunctional macroadenoma (NFA) of the pituitary remains controversial. Historically, immediate postoperative radiotherapy has been recommended to decrease risk of recurrence. With the availability of high-resolution imaging, most neurosurgeons now withhold radiation until recurrence. There is relatively little evidence to support this practice, however. This study reviews postoperative results in a large number of patients with NFA, the majority of whom did not undergo prophylactic radiation. METHODS:Of the 258 patients who underwent surgery from 1979 to 1999 for NFA, medical records were available for 176. Forty-four patients were treated with immediate postoperative radiotherapy after tumor resection, and the remaining 132 patients were followed up with serial imaging studies and treated with radiotherapy only when a recurrence was documented by follow-up imaging. RESULTS:Patients in the group that received immediate postoperative radiotherapy at time of initial diagnosis and surgery did not differ significantly with respect to age or sex from those in the group that was observed. Five- and 10-year recurrence rates were 2.3 and 2.3%, respectively, for patients who received immediate postoperative radiotherapy, as compared with 15.2 and 50.5%, respectively, for patients who were followed up and did not receive radiotherapy unless there was evidence of recurrence or progression. No patient had symptomatic recurrence in the group that was observed if consistent follow-up was performed. Of the 26 patients who received radiotherapy at time of tumor recurrence or progression, 18 had adequate follow-up, and in all cases, the tumors either remained stable or regressed. CONCLUSION:Withholding radiotherapy after a high-percentage resection of NFA leads to a higher recurrence rate, but it avoids exposing all patients to the risks of radiation. Deferring radiotherapy for patients with complete or near-complete resection seems to be a safe and prudent approach, as our data suggest that recurrences may be detected early with high-resolution imaging and treated effectively with radiation at time of recurrence. Therefore, immediate postoperative radiotherapy may be eliminated for patients with complete or near complete resection of NFA and who agree to undergo close follow-up for a long period.


Neurosurgery | 2006

Changes in the utilization of spinal fusion in the United States

John A. Cowan; Justin B. Dimick; Reid M. Wainess; Gilbert R. Upchurch; William F. Chandler; Frank La Marca

OBJECTIVE Several reports suggest that spine surgery has experienced rapid growth in the past decade. Limited data exist, however, documenting the increase in spinal fusion. The objective of this work was to quantify and characterize the contemporary practice of spinal fusion in the United States. METHODS Clinical data were obtained from the Nationwide Inpatient Sample for the years from 1993 to 2003. All patients with International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) procedure codes indicating cervical fusion, thoracolumbar fusion, lumbar or unspecified fusion were identified (n = 471,990). Primary ICD-9-CM diagnosis codes were used to determine the rationale for surgical fusion. Population-based utilization rates overall and for each procedure were calculated from United States census data. Rank order of spinal fusion compared with other inpatient procedures from the Nationwide Inpatient Sample was reported for the years 1997 to 2003. RESULTS Overall utilization increased during the time period for cervical, thoracolumbar, and lumbar fusions by 89, 31, and 134%, respectively. Patients aged 40 to 59 years experienced the rapid rise in utilization for cervical fusions (60-110 per 100,000) and lumbar fusions (35-84 per 100,000). For patients 60 years and older, utilization also increased for cervical (30-67 per 100,000), thoracolumbar (4-9 per 100,000), and lumbar (42-108 per 100,000). Spinal fusion rose from the 41st most common inpatient procedure in 1997 to the 19th in 2003. CONCLUSION Cervical, thoracolumbar, and lumbar spinal fusion have experienced a rapid increase in utilization in isolation and compared with other surgical procedures in contemporary practice. These changes are most pronounced for patients over 40 years of age, and degenerative disc disease seems to account for much of this increase.


The American Journal of Surgical Pathology | 1986

Ectopic pituitary adenomas with normal anterior pituitary glands

Ricardo V. Lloyd; William F. Chandler; Kalman Kovacs; Nancy Ryan

Two patients with ectopic pituitary adenomas and biopsy-proven normal anterior pituitaries are described. Both tumors were located in the sphenoid sinus. One tumor produced prolactin, and the other one was a plurihormonal adenoma that produced predominantly adrenocorticotropin and to a lesser extent thyroid stimulating hormone and alpha subunit. The patient with the plurihormonal tumor, who had Cushings disease, was cured by surgery while the patient with the prolactinoma was treated by surgery and medical therapy. A review of these two cases and an additional nine cases from the literature of ectopic pituitary adenomas in patients with normal intrasellar anterior pituitaries indicate that these uncommon tumors are capable of secretory function and may be the only cause of excessive pituitary hormone production.


Neurosurgery | 2003

Coregistration Accuracy and Detection of Brain Shift Using Intraoperative Sononavigation during Resection of Hemispheric Tumors

G. Evren Keles; Kathleen R. Lamborn; Mitchel S. Berger; Patrick J. Kelly; David W. Roberts; William F. Chandler; Ivan S. Ciric; Johannes Schramm; Dirk Van Roost

OBJECTIVESononavigation, which combines real-time anatomic ultrasound data with neuronavigation techniques, is a potentially valuable adjunct during the surgical excision of brain tumors. METHODSIn this study, we report our preliminary observations using this technology on 58 adult patients harboring hemispheric tumors. Data regarding coregistration accuracy was collected from various landmarks that typically do not shift as well as from tumor boundaries and the cortical surface. In a subset of patients, we evaluated the extent and direction of postresection brain displacement and its relationship with patient age, tumor histology, tumor volume, and use of mannitol. RESULTSFor all structures excluding the cortex, average coregistration accuracy measurements between ultrasound and preoperatively acquired magnetic resonance imaging scans were within the range of 2 mm. The most accurate alignments were obtained with the choroid plexus and the falx, and the least reliable structure in terms of coregistration accuracy was the cortical surface. CONCLUSIONSononavigation provides real-time information during tumor removal in alignment with the preoperative magnetic resonance imaging scans, thus enabling the surgeon to detect intraoperative hemorrhage, cyst drainage, and tumor resection, and it allows for calculation of brain shift during the use of standard navigation techniques.


Surgical Neurology | 2009

Dysphagia due to anterior cervical hyperosteophytosis.

Mark E. Oppenlander; Daniel A. Orringer; Frank La Marca; John E. McGillicuddy; Stephen E. Sullivan; William F. Chandler; Paul Park

BACKGROUND Anterior cervical hyperosteophytosis describes the excessive formation of osteophytes along the ventral spine. Dysphagia due to ACH is considered an uncommon entity described mainly in case reports. Symptomatic ACH has been attributed to multiple etiologies including DISH, trauma, postlaminectomy syndromes, and cervical spondylosis. We report one of the largest series of patients with ACH-induced dysphagia requiring surgery. METHODS After IRB approval, a retrospective chart review was completed. From 2001 to 2006, 9 patients presented with dysphagia due to ACH requiring surgical treatment. RESULTS Eight patients were male, and the mean age was 65.1 years. Cervical spine x-rays and CT clearly demonstrated ACH in each case. Esophagram or a video fluoroscopic swallowing study was used to verify that dysphagia was caused by osteophytic overgrowth in all instances but one. In 2 patients, a focal osteophyte had formed adjacent to a previously fused segment. Of the remaining 7 patients, osteophytic formation was attributed to cervical spondylosis in 2 patients and DISH in 5 patients. All patients underwent osteophytectomy without spinal fusion. Average follow-up was 9.8 months. Although all 9 patients experienced resolution of dysphagia, improvement was delayed in 2 patients. CONCLUSIONS Diffuse idiopathic skeletal hyperostosis and spondylosis are the most common etiologies accounting for ACH-induced dysphagia. Adjacent segment disease may also be a potential cause of symptomatic ACH and has not been previously reported. Regardless of etiology, surgical resection is highly successful if conservative measures fail.


Neurosurgery | 1986

Intracranial extension of orbital pseudotumor: a case report.

Susan Cline Noble; William F. Chandler; Ricardo V. Lloyd

A patient with intracranial extension of an orbital pseudotumor is reported. This rare consequence of an unusual inflammatory process has been reported on only two previous occasions. Our patient initially presented with unilateral loss of vision and a mass in the sphenoid sinus. Transsphenoidal biopsy revealed inflammatory tissue with a predominance of plasma cells. Over 2 years later, computed tomographic scanning demonstrated involvement of the ipsilateral frontal lobe, and craniotomy revealed invasion of both the dura mater and the cortex by this inflammatory process. Immunohistochemical staining for B and T cells was done to rule out lymphoma, and extensive cultures and staining were performed to identify any infectious process. Because this progressive lesion did not respond to steroid treatment, radiation therapy to the affected area was carried out. Orbital pseudotumor should be considered when an inflammatory process is identified in the meninges and cortex of the anterior fossa.


Neurosurgery | 1987

Cushing's syndrome caused by an ectopic pituitary adenoma.

David E. Schteingart; William F. Chandler; Ricardo V. Lloyd; Gloria Ibarra-Perez

A 49-year old woman with a 5-year history of Cushings syndrome was evaluated. Biochemical measurements revealed high cortisol and adrenocorticotropic hormone (ACTH) levels consistent with the ACTH-dependent type of Cushings syndrome. However, the source of ACTH seemed to be autonomous as she demonstrated abnormal feedback control, with lack of response to metyrapone and high coses of dexamethasone. A search for an ectopic ACTH-secreting nonpituitary neoplasm was unsuccessful. Transsphenoidal pituitary exploration revealed a normal pituitary gland, but an ectopic pituitary adenoma was found incidentally in the mucosa of the sphenoid sinus. This adenoma stained strongly positive for ACTH on immunocytochemical studies. Resection of this lesion led to remission of the Cushings syndrome. This variant of ACTH-dependent Cushings syndrome can mimic the ectopic ACTH-dependent type and should be looked for in patients who fail to respond to pituitary operation.


Neurosurgery | 1982

New implantable continuous administration and bolus dose intracarotid drug delivery system for the treatment of malignant gliomas

Timothy W. Phillips; William F. Chandler; Glenn W. Kindt; William D. Ensminger; Harry S. Greenberg; J. F. Seeger; Kate M. Doan; John W. Gyves

A totally implantable system for the continuous and bolus delivery of intra-arterial chemotherapeutic agents to patients with malignant gliomas is described. The system utilizes an Infusaid pump (Infusaid Corp., Sharon, Massachusetts), which discharges the drug directly into the internal carotid artery and is percutaneously refillable. This system has been utilized experimentally in primates and in the treatment of six patients with malignant gliomas. It seems that this system can be utilized safely as an experimental technique in the treatment of malignant gliomas.


The Annals of Thoracic Surgery | 1999

Epidural abscess: a delayed complication of esophageal stenting for benign stricture

Nicholas M. Boulis; Wendy S. Armstrong; William F. Chandler; Mark B. Orringer

A case of anterior cervical epidural abscess associated with perforation of an endoscopically placed esophageal stent is presented. Although delayed esophageal perforation is a known complication of endoscopic stenting, no cases presenting with epidural abscess have yet been reported. The increasing application of endoscopic stenting for benign esophageal strictures provides greater opportunity for this type of delayed complication.

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Larry Junck

University of Michigan

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Long Jin

University of Michigan

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