bluuebunny/crossref_metadata_2025_split huggingface dataset:
Percutaneous vertebroplasty in vertebral osteonecrosis (Kümmell's spondylitis)
Authors: Do Huy M. , Jensen Mary E. , Marx William F. , Kallmes David F. 
Published: January 2008

The authors report the clinical symptoms and response to therapy of a series of patients who presented with subacute or chronic back pain due to vertebral osteonecrosis (Kümmell's spondylitis) and who underwent percutaneous vertebroplasty.
The authors performed a retrospective chart review of a series of 95 patients in whom 149 painful, nonneoplastic compression fractures were demonstrated and who were treated with percutaneous transpediculate polymethylmethacrylate (PMMA) vertebroplasty. In six of these patients there was evidence of vertebral osteonecrosis, as evidenced by the presence of an intravertebral vacuum cleft on radiography or by intravertebral fluid on magnetic resonance (MR) imaging. Clinical and radiological findings on presentation were noted. Technical aspects of the vertebroplasty technique were compiled. Response to therapy, defined as qualitative change in pain severity and change in level of activity, was noted immediately following the procedure and at various periods on follow-up reviews.
One man and five women, who ranged in age from 72 to 90 years (mean 81 years), were treated. Each patient had one compression fracture. The fractures were at T-11 (one patient), L-1 (two patients), L-3 (two patients), and L-4 (one patient). The pain pattern was described as severe and localized to the affected vertebra, and sometimes radiated along either flank. Pain duration ranged from 2 to 12 weeks, and the pain was refractory to conservative therapy that consisted of bedrest, analgesics, and external bracing. At the time of treatment, all patients were bedridden because of severe back pain. In all patients either plain radiographic or computerized tomography evidence of intravertebral vacuum cleft or MR imaging evidence of vertebral fluid collection consistent with avascular necrosis of the vertebral body was demonstrated. Four patients underwent bilateral transpediculate vertebroplasty, and two patients underwent unilateral transpediculate vertebroplasty. The fracture cavities were specifically targeted for PMMA injection. Additional fortification of the osteoporotic vertebral body trabeculae was also performed when feasible. "Cavitygrams" or intraosseous venograms with gentle contrast injection were obtained prior to application of cement mixture. In all patients subjective improvement in pain and increased mobility were demonstrated posttreatment. The follow-up period ranged from 4 to 24 hours after treatment. Two patients made additional office visits at 1 and 3 months, respectively.
Patients presenting with vertebral osteonecrosis (Kümmell's spondylitis) often suffer from local paraspinous or referred pain. When performing vertebroplasty on these patients, confirmation of entry into the fracture cavities with contrast-enhanced "cavitygrams" should be performed prior to injection of PMMA cement. The response to vertebroplasty with regard to amelioration of pain and improved mobility is encouraging.
A new technique for the surgical management of unstable thoracolumbar burst fractures: a modification of the anterior approach and an outcome comparison to traditional methods
Authors: Wiggins Gregory C. , Rauzzino Michael J. , Shaffrey Christopher I. , Nockels Russ P. , Whitehill Richard , Shaffrey Mark E. , Wagner James , Alden Tord D. 
Published: January 2008

This study was conducted to determine the safety, efficacy, and complication rate associated with the anterior approach in the use of a new titanium mesh interbody fusion cage for the treatment of unstable thoracolumbar burst fractures. The experience with this technique is compared with the senior authors' (C.S., R.W., and M.S.) previously published results in the management of patients with unstable thoracolumbar burst fractures.
Between 1996 and 1999, 21 patients with unstable thoracolumbar (T12-L3) burst fractures underwent an anterolateral decompressive procedure in which a titanium cage and Kaneda device were used. Eleven of the 21 patients had sustained a neurological deficit, and all patients improved at least one Frankel grade (average 1.2 grades). There was improvement in outcome in terms of blood loss, correction of kyphosis, and pain, as measured on the Denis Pain and Work Scale, in our current group of patients treated via an anterior approach when compared with the results in those who underwent a posterior approach.
In our current study the anterior approach was demonstrated to be a safe and effective technique for the management of unstable thoracolumbar burst fractures. It offers superior results compared with the posterior approach. The addition of the new titanium mesh interbody cage to our previous anterior technique allows the patient's own bone to be harvested from the corpectomy site and used as a substrate for fusion, thereby obviating the need for iliac crest harvest. The use of the cage in association with the Kaneda device allows for improved correction of kyphosis and restoration of normal sagittal alignment in addition to improved functional outcomes.
Microsurgical anatomy of the extracranial-extradural origin of the posterior inferior cerebellar artery
Authors: Fine Andrew D. , Cardoso Alberto , Rhoton Albert L. 
Published: January 2008

Object
The authors describe the microsurgical anatomy of the posterior inferior cerebellar artery (PICA) with an extradural origin and discuss its importance as a common variation.

Methods
The microsurgical anatomy of paired PICAs with an extradural origin were examined.

Conclusions
Five to 20% of PICAs have an extradural origin. In the case described, both PICAs arose extradurally from the third segment of the vertebral artery (VA). Both origins were less than 1 cm proximal to the site at which the VA penetrated the dura and neither PICA gave rise to extradural branches. Extradurally the PICAs coursed parallel to the VA and the C-1 nerve and the three structures penetrated the dura together. Intradurally, the PICAs remained lateral and posterior to the brainstem, whereas, in the common PICA configuration, the first segment of the PICA courses anterior to the medulla. Neither PICA sent branches to the anterior brainstem, which is commonly found in PICAs with an intradural origin. There were no soft-tissue or bone anomalies.
Seven-year clinical experience with the Codman Hakim programmable valve: a retrospective study of 583 patients
Authors: Zemack Göran , Romner Bertil 
Published: January 2008

A retrospective study was undertaken to assess the value of the Codman Hakim programmable valve in the treatment of 583 patients (421 adults and 162 children) with hydrocephalus of various causes (379), normal-pressure hydrocephalus (NPH) (174), an arachnoidal cyst (14), and pseudotumor cerebri (16). In all patients the programmable valve was implanted (the valve can be noninvasively adjusted to settings in the range of 30-200 mm H2O). In 73% of the cases this was their first shunt implantation. Ninety-two percent of the shunts drained to the peritoneal cavity and 8% to the atrium. In 42% of the cases valve pressure adjustment was required at least once (mean number of adjustments 1.2, maximum 23).
The authors present reprogramming statistics, and strategies for reprogramming are discussed. In 65% of the cases in which pressure adjustments were required, reprogrammings improved the patients' clinical status. The overall infection rate was 8.5% (56 of 660 valve implantations). Valve malfunction, blockage, or reprogramming difficulty occurred in 17 cases, and nontraumatic subdural fluid collections were demonstrated in 30 cases (13 of which were treated by valve pressure reprogramming alone). Of the patients undergoing first-time shunt placement, 21.5% eventually underwent shunt revision at least once, and a total of 318 revisions were performed during the 7-year follow-up period. At follow up, 97% of children and 90% of adults had improved.
In conclusion, catheter-related complications and shunt-related infections were the main reasons for revision and the major cause of shunt failure. Few incidents of valve malfunction were observed. The Hakim Codman programmable valve is of value in the treatment of hydrocephalus of all causes, especially in the treatment of patients with NPH, pseudotumor cerebri, arachnoidal cyst, aqueductal stenosis, traumatic hydrocephalus, and intraventricular hemorrhage.
Risk factors for repeated cerebrospinal shunt failures in pediatric patients with hydrocephalus
Authors: Tuli Sagun , Drake James , Lawless Jerry , Wigg Melanie , Lamberti-Pasculli Maria 
Published: January 2008

Repeated cerebrospinal fluid (CSF) shunt failures in pediatric patients who have undergone neurosurgical procedures are common, and they are a significant cause of morbidity and occasionally mortality. To date, the risk factors for repeated failure have not been established. By performing survival analysis for repeated events, the authors examined the effects of patient characteristics, shunt hardware, and surgical details in a large cohort of patients.
During a 10-year period all pediatric patients with hydrocephalus requiring CSF diversionary procedures were included in a prospective single-institution observational study. Patient characteristics were defined as age, gender, weight, head circumference; American Society of Anesthesiology class, and the cause of hydrocephalus. Surgical details included whether the procedure was performed on an emergency or nonemergency basis, use of antibiotics, concurrent other surgical procedures, and the duration of surgical procedure. Details on shunt hardware included the type of shunt, the valve system, whether the shunt system included multiple or complex components, the type of distal catheter, site of the shunt, and side on which the shunt was placed.
Repeated shunt failures were assessed with multivariable time-to-event analysis (using the Cox regression model). Conditional models (as established by Prentice, et al.) were formulated for gap times (that is, times between successive shunt failures).
There were 1183 shunt failures in 839 patients. Failure time from the first shunt procedure was an important predictor for the second and third episodes of failures, thus establishing an association between the times to failure within individual patients. Age of less than 40 weeks gestation at time of the first shunt implantion carried a hazard ratio (HR) of 2.49 (95% confidence interval [CI] 1.68-3.68) for the first failure and remained high for subsequent episodes of failure. Age of 40 weeks to 1 year (at the time of the initial surgery) also proved to be an important predictor of first shunt malfunctions (HR 1.77, 95% CI 1.29-2.44). The cause of hydrocephalus was significantly associated with the risk of initial failure and, to a lesser extent, later failures. Concurrent other surgical procedures were associated with an increased risk of failure.
The patient's age at the time of initial shunt placement and the time interval since previous surgical revision are important predictors of repeated shunt failures in the multivariable model. Even after adjusting for age at first shunt insertion as well as the cause of hydrocephalus there is significant association between repeated failure times for individual patients.
Comparative neuroprotective efficacy of prolonged moderate intraischemic and postischemic hypothermia in focal cerebral ischemia
Authors: Huh Pil W. , Belayev Ludmila , Zhao Weizhao , Koch Sebastian , Busto Raul , Ginsberg Myron D. 
Published: January 2008

Object
The purpose of this study was to compare the effects of prolonged hypothermia on ischemic injury in a highly reproducible model of middle cerebral artery (MCA) occlusion in rats.

Methods
Male Sprague-Dawley rats were anesthetized with halothane and subjected to 120 minutes of temporary MCA occlusion by retrograde insertion of an intraluminal nylon suture coated with poly-L-lysine through the external carotid artery into the internal carotid artery and the MCA. Two levels of prolonged postischemic cranial hypothermia (32°C and 27°C), and one level of intraischemic cranial hypothermia (32°C) were compared with the ischemic normothermia (37°C) condition. Target cranial temperatures were maintained for 3 hours and then gradually restored to 35°C over an additional 2-hour period. The animals were evaluated using a quantitative neurobehavioral battery of tests before inducing MCA occlusion, during occlusion (at 60 minutes postonset in all rats except those in the intraischemic hypothermia group), and at 24, 48, and 72 hours after reperfusion. The rat brains were perfusion fixed at 72 hours after ischemia and infarct volumes and brain edema were determined. Both intraischemic and postischemic cooling to 32°C led to similar significant reductions in cortical infarct volume (by 89 and 88%, respectively) and total infarct volume (by 54 and 69%, respectively), whereas postischemic cooling to 27°C produced lesser reductions (64 and 49%, respectively), which were not statistically significant. All three hypothermic regimens significantly lessened hemispheric swelling and improved the neurological score at 24 hours. Our data confirm that a high degree of histological neuroprotection is conferred by postischemic cooling to 32°C, which is virtually equivalent to that observed with intraischemic cooling to the same level.

Conclusions
These results may be relevant to the design of future clinical trials of therapeutic hypothermia for acute ischemic stroke.
Thoracoscopic correction and placement of anterior instrumentation for scoliotic deformity
Authors: Dickman Curtis A. 
Published: January 2008

Correction of rigid scoliotic deformities involving the thoracic spine has required that a thoracotomy be performed to obtain anterior release to mobilize the deformity, as well as placement of corrective spinal instrumentation either via a separate posterior or anterior thoracic approach. To the best of the author's knowledge, this is the first published report of a case in which anterior correction of a deformity was achieved endoscopically.
A 27-year-old man presented with a rigid 85° thoracic kyphoscoliotic deformity that had developed over several years. He had previously undergone a C7-T12 laminectomy to decompress the spinal cord from a lipoma. Using thoracoscopic techniques, the author performed an anterior release and interbody fusion. Endoscopically, an anterior screw/rod system applied from T-5 to T-9 corrected the deformity to 55°.
There were no surgery-related complications. At follow-up examiniation 1.5 years after surgery, the patient had developed a solid fusion and the correction was maintained at an angle of 58°.
It is feasible to use thoracoscopic techniques to perform an anterior release and to apply anterior corrective spinal instrumentation to treat thoracic scoliotic deformities, thereby avoiding the need for an open posterior approach in which instrumentation is placed.
Retrosigmoid intradural suprameatal approach to Meckel's cave and the middle fossa: surgical technique and outcome
Authors: Samii Madjid , Tatagiba Marcos , Carvalho Gustavo A. 
Published: January 2008

Object
The goal of this study was to determine whether some petroclival tumors can be safely and efficiently treated using a modified retrosigmoid petrosal approach that is called the retrosigmoid intradural suprameatal approach (RISA).

Methods
The RISA was introduced in 1983, and since that time 12 patients harboring petroclival meningiomas have been treated using this technique. The RISA includes a retrosigmoid craniotomy and drilling of the suprameatus petrous bone, which is located above and anterior to the internal auditory meatus, thus providing access to Meckel's cave and the middle fossa.
Radical tumor resection (Simpson Grade I or II) was achieved in nine (75%) of the 12 patients. Two patients underwent subtotal resection (Simpson Grade III), and one patient underwent complete resection of tumor at the posterior fossa with subtotal resection at the middle fossa. There were no deaths or severe complications in this series; all patients did well postoperatively, being independent at the time of their last follow-up examinations (mean 5.6 years). Neurological deficits included facial paresis in one patient and worsening of hearing in two patients.

Conclusions
The approach described here is a useful modification of the retrosigmoid approach, which allows resection of large petroclival tumors without the need for supratentorial craniotomies. Although technically meticulous, this approach is not time consuming; it is safe and can produce good results. This is the first report on the use of this approach for petroclival meningiomas.
Treatment of progressive or recurrent pediatric malignant supratentorial brain tumors with herpes simplex virus thymidine kinase gene vector--producer cells followed by intravenous ganciclovir administration
Authors: Packer Roger J. , Raffel Cory , Villablanca Judith G. , Tonn Jörg-Christian , Burdach Stefan E. , Burger Klaus , LaFond Deborah , McComb J. Gordon , Cogen Philip H. , Vezina Gilbert , Kapcala Leonard P. 
Published: January 2008

Object
The outcome for children with recurrent malignant brain tumors is poor. The majority of patients die of progressive disease within months of relapse, and other therapeutic options are needed. The goal of this Phase I study was to evaluate the safety of in vivo suicide gene therapy in 12 children with recurrent, malignant, supratentorial brain tumors.

Methods
After optimal repeated tumor resection, multiple injections of murine vector--producing cells shedding murine replication--defective retroviral vectors coding the herpes simplex virus thymidine kinase type 1 (HSV-Tk1) gene were made into the rim of the resection cavity. Fourteen days after the vector-producing cells were injected, ganciclovir was administered for 14 days. The retroviral vector that was used only integrated and expressed HSV-Tk1 in proliferating cells, which are killed after a series of metabolic events lead to cell death. The median age of the patients was 11 years (range 2--15 years). Treated brain tumors included seven malignant gliomas, two ependymomas, and three primitive neuroectodermal tumors. The patients were treated with one of three escalating dose concentrations of vector-producer cells. Four transient central nervous system adverse effects were considered possibly related to the vector-producing cells. In no child did permanent neurological worsening or ventricular irritation develop, and tests for replication-competent retroviruses yielded negative findings.

Conclusions
This Phase I study demonstrates that in vivo gene therapy in which a replication-defective retroviral vector in murine vector--producing cells is delivered by brain injections can be performed with satisfactory safety in a select group of children with localized supratentorial brain tumors.
Minimally invasive retroperitoneal approach for lumbar corpectomy and reconstruction
Authors: Mühlbauer Manfred , Pfisterer Wolfgang , Eyb Richard , Knosp Engelbert 
Published: January 2008

Anterior decompressive surgery with spinal fusion is considered an effective treatment for thoracolumbar fractures and tumors. However, it is also known to be associated with considerable surgical approach–related trauma. The purpose of this study was to show that lumbar corpectomy and spinal reconstruction can be performed via a minimally invasive retroperitoneal (MIR) approach and therefore, the surgical approach–related trauma can be reduced.
The hospital records and radiological studies obtained in five patients (mean age 67.4 years, range 59-76 years) who underwent lumbar corpectomy and spinal fusion via an MIR approach were studied retrospectively. Four patients presented with osteoporotic compression fractures at L-2 and L-3 and one patient with metastatic disease at L-4 from prostate cancer. In all patients neurological deficits due to cauda equina compression were demonstrated.
The MIR approach provided excellent exposure to facilitate complete spinal decompression and reconstruction in all patients, as verified on follow-up x-ray studies. All patients improved clinically. A 1-year follow-up record, available for four patients, showed evidence of continuing clinical improvement and, radiographically, a solid fusion or a stable compound union and anatomically correct reconstruction.
The MIR approach allows anterior lumbar spine surgery to be performed less invasively. The efficacy and safety of this technique compared with the conventional retroperitoneal approach to lumbar spine surgery should be further investigated in a larger series.
The influence of cranioplasty on postural blood flow regulation, cerebrovascular reserve capacity, and cerebral glucose metabolism
Authors: Winkler Peter A. , Stummer Walter , Linke Rainer , Krishnan Kartik G. , Tatsch Klaus 
Published: January 2008

The indications for cranioplasty after decompressive craniectomy are cosmetic repair and, mainly, restoration of cerebral protection. Although neurological improvement after cranioplasty is repeatedly noted, the reasons for this still remain unclear. Few observations concerning the impact of CSF hydrodynamic and/or atmospheric pressure were published during the last decades. Relevant data concerning the cerebrovascular reserve capacity and cerebral glucose metabolism before and after cranioplasty have been lacking until now. To gain further insight, the present study was undertaken to investigate the impact of cranioplasty on indices of cerebral blood flow regulation and metabolism.
Thirteen patients in whom extensive craniectomies had been performed underwent a meticulous study of blood flow velocities in the middle cerebral artery (MCA) and extracranial internal carotid artery (ICA), as assessed by transcranial Doppler (TCD) ultrasonography during postural maneuvers (supine and sitting positions) and during stimulation with 1 g of acetazolamide for the interpretation of cerebrovascular reserve (CVR) capacity. Twelve patients underwent 18-fluorodesoxyglucose positron emission tomography. These measurements were made before and 7 days after cranioplasty.
Cranioplasty improved preoperative differences in MCA blood flow velocities when comparing the injured with the noninjured hemisphere. Similarly, cranioplasty resolved decreases in extracranial ICA blood flow in the injured hemisphere that were induced by postural changes, which was a constant finding prior to this procedure. More strikingly, however, the CVR capacity, which was severely impaired in both hemispheres, significantly increased after the procedure. Metabolic deficits, which were observed in the injured as compared with the noninjured hemisphere, were found to improve after reimplantation of the skull bone flap.
Cranioplasty appears to affect postural blood flow regulation, CVR capacity, and cerebral glucose metabolism markedly. Thus, early cranioplasty is warranted to facilitate rehabilitation in patients after decompressive craniectomy.