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John R. Vender and Karin Bierbrauer

✓Depressed skull fractures overlying the major venous sinus are often managed nonoperatively because of the high associated risks of surgery in these locations. In the presence of clinical and radiographic evidence of sinus occlusion, however, surgical therapy may be necessary. The authors present the case of a 9-year-old boy with a depressed skull fracture overlying the posterior third of the superior sagittal sinus. After initial conservative treatment, delayed signs of intracranial hypertension and a symptomatic tonsillar herniation with tonsillar necrosis developed. Possible causes as well as diagnostic and treatment options are reviewed.

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Betsy D. Hughes and John R. Vender

✓Bullet fragment emboli are uncommon, and there have been only a few reports of intracranial-to-extracranial migration of these fragments. The authors present the case of an 11-year-old girl who was struck in the suboccipital region with a “soft nose” bullet fired at close range. Several months later, the patient was found to have asymptomatic pulmonary emboli. Similar cases are reviewed, and a management strategy is recommended.

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Craig H. Rabb

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John R. Vender, Jason Miller, Andy Rekito and Dennis E. McDonnell

Hemostatic options available to the surgeon in the late 19th and early 20th centuries were limited. The surgical ligature was limited in value to the neurological surgeon because of the unique structural composition of brain tissue as well as the approaches and operating angles used in this type of surgery. In this manuscript the authors review the options available and the evolution of surgical hemostatic techniques and electrosurgery in the late 19th and early 20th centuries and the impact of these methods on the surgical management of tumors of the brain and its coverings.

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J. Nicole Bentley, Ramón E. Figueroa and John R. Vender

Cerebral venous thrombosis is an uncommon cause of stroke but remains a challenge for physicians faced with this diagnosis largely due to the variability in presentation. Anticoagulation, typically with intravenous heparin, remains the mainstay of treatment for stable patients and is sufficient in the majority of cases. However, a significant mortality rate exists for cerebral venous thrombosis due to patients who deteriorate or do not adequately respond to initial treatments. It is in these patients that more aggressive interventions must be undertaken. The neurosurgeon is often called on, either acutely for initial evaluation of the stroke or venous hemorrhage or after the failure of initial therapy for clot evacuation, hemicraniectomy, or thrombectomy. A proper workup must include a search for an underlying, correctable cause as well as thorough follow-up with correction of identified risk factors to decrease the risk of recurrent disease.

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John R. Vender, Steven J. Harrison and Dennis E. McDonnell

Object. The high anterior cervical, retropharyngeal approach to the anterior foramen magnum and upper cervical spine is a favorable alternative to the transoral and posterolateral approaches, which both cause instability of the craniovertebral junction. Previously, such instability was corrected via an occipitocervical fusion during a separate surgical procedure.

Methods. Seven patients requiring C-2 corpectomy (foramen magnum meningioma [two patients], critical stenosis secondary to rheumatoid arthritis [two patients], C-2 fracture [two patients], and stenosis secondary to Rickets [one patient]) are presented. All patients underwent C1–3 fusion followed by instrumentation with a Caspar plate. A solid fusion was achieved in six patients. One patient experienced erosion of the anterior arch of C-1 requiring posterior stabilization.

Conclusions. Fusion and instrumentation at C1–3 can be performed safely and with minimal increase in surgical time. In selected patients, this may eliminate the need for an additional posterior procedure and maintain occipital—C1 mobility.

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Sydney M. Hester, John F. Fisher, Mark R. Lee, Samuel Macomson and John R. Vender

Object

Intrathecal baclofen therapy has been used successfully for intractable spasticity in children with cerebral palsy. Infections are rare, but they are potentially life threatening if complicated by bacteremia or meningitis. Treatment without removal of the system is desirable if it can be done safely and effectively.

Methods

The authors reviewed the records of 207 patients ranging from 3 to 18 years of age with cerebral palsy who underwent placement or revision of a baclofen pump. They identified 38 patients with suspected or documented infectious complications. Initial attempts were made to eradicate infection with the devices in situ in all patients. Methods and effectiveness of pump salvage were evaluated.

Results

Of the 38 patients identified, 13 (34.2%) had documented infections; 11 had deep wound/pocket empyemas and 2 had meningitis. Eight patients with deep wound infections received intravenous antibiotics alone. All required pump explantation. The remaining 3 patients underwent a washout procedure as well; the infection was cured in 1 patient. Both patients with meningitis received intravenous and intrathecal antibiotics, and both required device explantation. In addition, 25 patients (65.8%) had excessive or increasing wound erythema. No objective criteria to document a superficial infection were present. The wounds were considered suspicious and were managed with serial examinations and oral antibiotics. The erythema resolved in 24 of the 25 patients.

Conclusions

In general, observation, wound care, and oral antibiotics are sufficient for wounds that are suspicious for superficial infection. For deep-seated infection, antibiotic therapy alone is generally insufficient and explantation is required. Washout procedures can be considered, but failures are common.

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Scott Y. Rahimi, Cargill H. Alleyne Jr., Eric Vernier, Mark R. Witcher and John R. Vender

Object

Patients undergoing craniotomies have traditionally received opiates with acetaminophen for the management of their postoperative pain. The use of narcotic pain medications can be costly, decrease rates of early postoperative ambulation, lengthen hospital stays, and alter a patient's neurological examination. The use of alternative pain medications such as tramadol may benefit patients by resolving many of these issues.

Methods

The authors conducted a randomized, blinded prospective study to evaluate the efficacy of alternative pain management strategies for patients following craniotomies. Fifty patients were randomly assigned either to a control group who received narcotics and acetaminophen alone or an experimental group who received tramadol in addition to narcotic pain medications (25 patients assigned to each group).

Results

The control group was noted to have statistically significant higher visual analog scale pain scores, an increased length of hospital stay, and increased narcotic use compared with the tramadol group. The narcotics and acetaminophen group also had increased hospitalization costs when compared with the tramadol group.

Conclusions

The use of scheduled atypical analgesics such as tramadol in addition to narcotics with acetaminophen for the management of postoperative pain after craniotomy may provide better pain control, decrease the side effects associated with narcotic pain medications, encourage earlier postoperative ambulation, and reduce total hospitalization costs.

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John R. Vender, Sydney Hester, Jennifer L. Waller, Andy Rekito and Mark R. Lee

Object

Intrathecal baclofen therapy is an effective means of treating intractable spasticity and dystonia in the pediatric and adult population. The authors present a review of complications encountered in a series of 314 pump and catheter-related procedures. The identification and management of these complications will be reviewed. The authors will also identify populations that may be at increased risk for complications.

Methods

A retrospective review was performed of all procedures undertaken during the last 5 years by two surgeons at the authors' institution. Postoperative complications were reviewed.

A total of 314 surgical procedures (226 pediatric and 88 adult) were performed in 195 pediatric and adult patients. This included 171 new pump and catheter implants (116 pediatric and 55 adult), 26 elective pump replacements due to end of battery life (15 pediatric and 11 adult), five elective pump repositionings per physiatrist request (three pediatric and two adult), 14 elective catheter repositionings (10 pediatric and four adult), and two normal pediatric catheter explorations. Surgical procedures for complication management included seven pump revisions (five pediatric and two adult), 48 catheter revisions (38 pediatric and 10 adult), and 41 wound revisions (37 pediatric and four adult). The majority of adult pumps were implanted subdermally, whereas in pediatric patients they were placed subfascially. In general, intrathecal catheters were placed under fluoroscopic guidance with the catheter tip placed at T-1 to T-2 for spastic quadriplegia, T-6 to T-10 for spastic diplegia, and midcervical for dystonia. No significant intraoperative complications were encountered. Overall, there was a statistically significantly higher percentage of procedures for overall complication management and wound complication management in pediatric patients compared with adult patients.

Conclusions

Intrathecal baclofen therapy is a highly effective treatment option for patients with medically refractory spasticity. The catheter, pump, and wound are subject to numerous complications both at the time of implantation and throughout the life of the implanted system. Careful technique, close observation, and aggressive evaluation and correction of problems can reduce the incidence and severity of the complications when they occur.

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Sangeetha Sukumari-Ramesh, Nagendra Singh, Michael A. Jensen, Krishnan M. Dhandapani and John R. Vender

Object

Pituitary adenomas, which are common intracranial tumors, are associated with significant patient morbidity due to hormone secretion or mass effect or as a complication of therapy. Epigenetic regulation has emerged as an important component of malignant tumor pathogenesis, although the contribution in the progression of benign pituitary tumors remains largely unexplored. The present study evaluates the effect of anacardic acid (6-pentadecyl salicylic acid), a natural histone acetyltransferase inhibitor, on pituitary adenoma cells.

Methods

The concentration- and time-dependent effects of anacardic acid on the viability of GH3 and MMQ pituitary adenoma cells were determined by 3-(4,5-dimethylthiazoyl-2-yl)-2,5-diphenyltetrazolium bromide assay. Cell cycle phase distribution, protein expression, and percentage of apoptotic cells were assessed by flow cytometry and Western blotting. Colony forming assays were used to study the radiosensitizing effect of anacardic acid.

Results

The present study identifies a novel antiproliferative and cytotoxic effect of anacardic acid on pituitary adenoma cells. These effects were associated with an increase in poly([adenosine diphosphate]-ribose) polymerase cleavage, sub-G1 arrest, and annexin V staining, consistent with apoptotic cell death; however, the pancaspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-(O-methyl)-fluoromethylketone failed to reverse anacardic acid–induced cell death, suggesting a possible nonclassical apoptotic mechanism. Anacardic acid also reduced the expression of survivin and X-linked inhibitor of apoptosis protein, antiapoptotic proteins associated with cellular survival and radioresistance, and radiosensitized pituitary adenoma cells.

Conclusions

These findings warrant further exploration of anacardic acid as a single agent or as an adjunct to radiation therapy for the treatment of pituitary tumors.