bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atypical teratoid/rhabdoid tumors of the central nervous system: management and outcomes
Authors: Chen Michael L. , McComb J. Gordon , Krieger Mark D. 
Published: January 2008

Object
Atypical teratoid/rhabdoid tumors (ATRTs) represent a relatively newly categorized neoplastic entity. They commonly present in childhood, and have a rapidly progressive clinical course with a survival time of less than 1 year. Treatment regimens have been nonuniform. In this retrospective review of patients with ATRTs who were treated at the authors' institution according to a uniform protocol, the goal was to assess the efficacy of the treatment and its outcome.

Methods
Over a 7-year period, ATRT was diagnosed in 11 patients (six boys and five girls). The median age of the patients was 61 months, and their ages ranged from 3 months to 17 years. Signs and symptoms began, on average, a little more than 1 month before diagnosis and included the following: headache (36%), nausea and vomiting (46%), lethargy (18%), seizures (27%), cranial nerve findings (46%), ataxia (18%), long tract findings (18%), and hydrocephalus (46%). Tumor location was cortical in four patients, in the pineal region in four, in the posterior fossa in two, and spinal in one. In one patient disseminated disease was revealed on the initial imaging study; seven patients had disseminated tumor subsequently. Treatment consisted of chemotherapy in 11 patients, chemotherapy and local radiation in five, and chemotherapy and craniospinal radiation in three. Six patients are alive, three have died, and two were lost to follow-up review. The mean time to death was 24 months, and ranged from 2 to 67 months. Among the surviving patients the mean duration of follow up is 18.5 months and ranges from 2 to 37 months. The median time to progression was 3.5 months.

Conclusions
Atypical teratoid/rhabdoid tumors are malignant lesions with rapid progression. Further study is necessary to determine the efficacy of therapy.
Expanded endonasal approach: fully endoscopic, completely transnasal approach to the middle third of the clivus, petrous bone, middle cranial fossa, and infratemporal fossa
Authors: Kassam Amin B. , Gardner Paul , Snyderman Carl , Mintz Arlan , Carrau Ricardo 
Published: January 2008

Object
The middle third of the clivus and the region around the petrous internal carotid artery (ICA) is a difficult area of the skull base in terms of access. This is a deep area rich with critical neurovascular structures, which is often host to typical skull base diseases. Expanded endoscopic endonasal approaches offer a potential option for accessing this difficult region. The objective of this paper was to establish the clinical feasibility of gaining access to the paraclival space in the region of the middle third of the clivus, to provide a practical modular and clinically applicable classification, and to describe the relevant critical surgical anatomy for each module.

Methods
The anatomical organization of the region around the petrous ICA, cavernous sinus, and middle clivus is presented, with approaches divided into zones. In an accompanying paper in this issue by Cavallo, et al., the anatomy of the pterygopalatine fossa is presented; this was observed through cadaveric dissection for which an expanded endonasal approach was used. In the current paper the authors translate the aforementioned anatomical study to provide a clinically applicable categorization of the endonasal approach to the region around the petrous ICA. A series of zones inferior and superior to the petrous ICA are described, with an illustrative case presented for each region.

Conclusions
The expanded endonasal approach is a feasible approach to the middle third of the clivus, petrous ICA, cavernous sinus, and medial infratemporal fossa in cases in which the lesion is located centrally, with neurovascular structures displaced laterally.
Generating chimeric spinal cord: a novel model for transplantable oligodendrocyte progenitors derived from embryonic stem cells
Authors: Vadivelu Sudhakar , Becker Daniel , McDonald John W. 
Published: January 2008

Object
To identify and evaluate stem cell–derived oligodendrocytes obtained for cell transplantation therapies, the authors developed a novel model to examine single, adult oligodendrocytes in situ.

Methods
Green fluorescent protein–expressing, mouse embryonic stem cells (ESCs) were neural induced and additionally staged in an oligosphere preparatory step for high-yield derivation of oligodendrocyte progenitors. These transplantable, induced progenitors were injected into postnatal Day 2 rat pups, in which spinal cord sections were then examined at 3 and 9 weeks posttransplantation.

Conclusions
Transplanted oligosphere ESCs survived and integrated anatomically into postnatal and adult white matter, generating targeted regions of chimeric spinal cord. A simple model for identifying adult oligodendrocytes in situ is presented, which is suitable for use in further studies examining functional myelination and derivation of oligodendrocytes from genetically engineered ESC lines, including human ESCs. Results from the model presented here demonstrate a unique method for examining transplantable oligodendrocyte progenitors derived from ESCs for repair of white matter disease.
Use of a simple intraoperative hydrostatic pressure test to assess the relationship between mobility of the ventricular stoma and success of third ventriculostomy
Authors: Kamel Mahmoud Hamdy , Kelleher Michael , Aquilina Kristian , Lim Chris , Caird John , Kaar George 
Published: January 2008

Object
Neuroendoscopists often note pulsatility or flabbiness of the floor of the third ventricle during endoscopic third ventriculostomy (ETV) and believe that either is a good indication of the procedure's success. Note, however, that this belief has never been objectively measured or proven in a prospective study. The authors report on a simple test—the hydrostatic test—to assess the mobility of the floor of the third ventricle and confirm adequate ventricular flow. They also analyzed the relationship between a mobile floor (a positive hydrostatic test) and prospective success of ETV.

Methods
During a period of 3 years between July 2001 and July 2004, 30 ETVs for obstructive hydrocephalus were performed in 22 male and eight female patients. Once the stoma had been created, the irrigating Ringer lactate solution was set at a 30-cm height from the external auditory meatus, and the irrigation valve was opened while the other ports on the endoscope were closed. The ventricular floor ballooned downward and stabilized. The irrigation valve was then closed and ports of the endoscope were opened. The magnitude of the upward displacement of the floor was then assessed. Funneling of the stoma was deemed to be a good indicator of floor mobility, adequate flow, and a positive hydrostatic test. All endoscopic procedures were recorded using digital video and recordings were subsequently assessed separately by two blinded experienced neuroendoscopists. Patients underwent prospective clinical follow up during a mean period of 11.2 months (range 1 month–3 years), computerized tomography and/or magnetic resonance imaging studies of the brain, and measurements of cerebrospinal fluid pressure through a ventricular reservoir when present. Failure of ETV was defined as the subsequent need for shunt implantation. The overall success rate of the ETV was 70% and varied from 86.9% in patients with a mobile stoma and a positive hydrostatic test to only 14.2% in patients with a poorly mobile floor and a negative test (p < 0.05). The positive predictive value of the hydrostatic test was 86.9%, negative predictive value 85.7%, sensitivity 95.2%, and specificity 66.6%.

Conclusions
The authors concluded that the hydrostatic test is an easy, brief test. A positive test result confirms a mobile ventricular floor and adequate flow through the created ventriculostomy. Mobility of the stoma is an important predictor of ETV success provided that there is no obstruction at the level of the arachnoid granulations or venous outflow. A thin, redundant, mobile third ventricle floor indicates a longstanding pressure differential between the third ventricle and the basal cisterns, which is a crucial factor for ETV success. A positive hydrostatic test may avert the need to insert a ventricular reservoir, thus avoiding associated risks of infection.
Detected and overlooked cervical spine injury among comatose trauma patients: from the Pennsylvania trauma outcomes study
Authors: Piatt Joseph H. 
Published: January 2008

Object
A rule for identifying patients with traumatic brain injury (TBI) who are at exceptionally low risk of cervical spine injury might be clinically useful. The goal in this study was to research case records to determine whether such a rule would be practicable.

Methods
The Pennsylvania Trauma Outcomes Study database was used to find patients with TBI in whom Glasgow Coma Scale (GCS) scores at admission were 8 or less. Cases of cervical spine injury were identified from diagnostic codes. Associations between these injuries and a variety of clinical variables were tested using chi-square analysis. The probability of a cervical spine injury in these patients was modeled by logistic regression. Decision tree models were constructed and statistical determinants of overlooked cervical spine injury were examined.
The prevalence of cervical spine injury among 41,142 cases of TBI was 8%. The mechanism of injury, presence of thoracolumbosacral (TLS) spinal, limb and/or facial fracture, patient age, GCS score at admission, and the presence of hypotension were all factors associated with cervical spine injury. These were incorporated into the following logistic regression model: probability of cervical spine injury = 1/(1 + exp[4.030 − 0.417*mechanism − 0.264*age − 0.678*TLS − 0.299*limb + 0.218*GCS score − 0.231*hypotension − 0.157*facial]).
This model yielded a rule for clearance of 28% of cases, with a negative predictive value (NPV) of 97%. Decision tree analysis yielded an easily stated rule for clearance of 24% of cases, with an NPV of 98.2%. The prevalence of overlooked cervical spine injury among all patients with severe TBI was 0.3%; the prevalence of overlooked cervical spine injury among patients in whom it was later diagnosed was 3.9%. Overlooked cervical spine injury was less common among patients with associated TLS fractures (odds ratio 0.453, 95% confidence interval 0.245–0.837).

Conclusions
No acceptable rule for relaxation of vigilance in the search for cervical spine injury among patients with severe TBI has been identified. Levels of provider vigilance and consequent rates of overlooked cervical spine injury can be affected by environmental cues and presumably by other behavioral and organizational factors.
Microelectrode recording-determined subthalamic nucleus length not predictive of stimulation-induced side effects
Authors: McClelland Shearwood , Kim Brian , Winfield Linda M. , Ford Blair , Edwards Tresha A. , Pullman Seth L. , Yu Qiping , McKhann Guy M. , Goodman Robert R. 
Published: January 2008

Object
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become a popular treatment for patients with medically refractory Parkinson disease. Many surgeons believe that microelectrode recording (MER) during DBS electrode implantation is needed to optimize placement, whereas stimulation-induced side effects such as paresthesias, dystonic contractions, dyskinesias, and ocular motor signs that become apparent postoperatively may be an indicator of the proximity of the electrode to various boundaries of the STN. This study was performed to evaluate the relationship between mapping of the STN by using MER and postoperative stimulation-induced side effects.

Methods
Eighty-two electrodes implanted in 75 patients between March 1999 and March 2003 were retrospectively examined to evaluate the length of the STN defined by MER, and the number of and threshold for postoperative stimulation-induced side effects. Electrodes were typically tested with increasing stimulation amplitudes (maximum 6 V) by using a monopolar array.
The 82 electrodes were associated with 97 stimulation-induced side effects. The mean time between surgery and testing stimulation-induced side effects was 3.9 months. Statistical analysis (two-tailed t-test) revealed no significant difference in the number of stimulation-induced side effects (or the mean threshold for paresthesias, the most common side effect) for electrodes associated with an STN length less than 4.5 mm (13 electrodes) compared with those associated with an STN greater than or equal to 4.5 mm (69 electrodes, p = 0.616). For every electrode, the target adjustment based on MER results was within 2 mm of the image-planned target (usually 1 mm anterior). In the x axis (medial–lateral orientation), there was no systematic difference in adjustments made for the electrodes associated with the shorter compared with the longer STN lengths. In the y axis (anterior–posterior orientation), there was a very small statistically significant difference in the mean adjustment (0.4 mm) between the two groups.

Conclusions
Analysis of these results suggests that a shorter MER-determined STN length alone does not reliably predict the incidence of stimulation-induced side effects.
Arachnoid cyst resulting in tonsillar herniation and syringomyelia in a patient with achondroplasia
Authors: Bauer Andrew M. , Mueller Diane M. , Oró John J. 
Published: January 2008

Achondroplasia has been associated with varying degrees of cervicomedullary and spinal compression, although usually in the pediatric population. Large arachnoid cysts have also been found to result in tonsillar herniation and syringomyelia. The authors present the case of a patient with achondroplasia who presented with symptoms of foramen magnum compression and syringomyelia, and who was subsequently found to have a large posterior fossa arachnoid cyst.
This 38-year-old woman with achondroplasia presented with an 8-month history of headache and numbness of the hands and fingers. Admission magnetic resonance (MR) imaging of the head and spine revealed a large arachnoid cyst in the posterior cranial fossa, a 6-mm tonsillar herniation consistent with an acquired Chiari malformation, and a large cervicothoracic syrinx. The patient was treated using suboccipital craniectomy, C-1 laminectomy, fenestration of the arachnoid cyst, and decompression of the acquired Chiari malformation with duraplasty.
Surgical decompression resulted in improvement of the presenting symptoms, adequate decompression of crowding at the foramen magnum, and resolution of the syrinx. Although there was only partial reduction in the retrocerebellar cisternal space on follow-up MR imaging, no residual symptoms were related to this.
Endoscopic-assisted repair of craniosynostosis
Authors: Murad Gregory J. A. , Clayman Mark , Seagle M. Brent , White Sno , Perkins Leigh Ann , Pincus David W. 
Published: January 2008

Object
The goal of the craniofacial surgeon has always been the correction of form and function with prevention of associated morbidity and death. Through the pioneering work of Jimenez and Barone, minimally invasive approaches to the surgical correction of craniosynostosis are now gaining wider acceptance. Here the authors review the technique for endoscopic-assisted repair of craniosynostosis from the perspective of a new minimally invasive approach. They also assess the safety, efficacy, and results of the early treatment of infants with craniosynostosis in a small series of children who underwent surgery at this institution.

Methods
Data regarding synostosis type, operative time, patient age, blood loss, transfusion rates, duration of hospitalization, and complications were collected. Nineteen patients (12 girls and seven boys) between the ages of 1.2 and 5 months of age were treated with the endoscope-assisted technique. The mean operative time was 97 minutes. Five (26%) of 19 children received a blood transfusion. Most patients were discharged home the morning after surgery. The clinical courses of two patients who required additional major craniofacial reconstructions are discussed. There were no deaths, dural sinus tears, cerebrospinal fluid leaks, neurological injuries, or infections, and there were no complications related to the use of helmet therapy. Seventeen of the 19 patients achieved excellent cosmetic results with a single surgery.

Conclusions
This small series supports larger experiences and indicates that early treatment of craniosynostosis with minimally invasive, endoscope-assisted techniques is safe; limits blood transfusion, hospital stay, and operative time; and represents a valuable alternative to the traditional calvarial reconstruction methods.
Endoscopic management of intracranial cysts
Authors: Greenfield Jeffrey P. , Souweidane Mark M. 
Published: January 2008

Object
Endoscopic fenestration has been recognized as an accepted treatment choice for patients with symptomatic arachnoid cysts. The success of this procedure, however, is greatly influenced by individual cyst anatomy and location as well as the endoscopic technique used. This review was conducted to assess what variables influence the treatment success for different categories of arachnoid cysts.

Methods
Thirty-three consecutive patients who underwent endoscopic fenestration for treatment of an intracranial arachnoid cyst were identified from a prospective database. The surgical indications and techniques were reviewed, and surgical success rates and patient outcomes were assessed. Specific examples of each cyst category are included to illustrate the technical aspects of endoscopic cyst fenestration.
Endoscopic fenestration of arachnoid cysts was successful when judged by cyst decompression, and symptom resolution was noted in 32 (97%) of 33 cases. The one patient with short-term treatment failure underwent a successful repetition of the operation. There were no surgery-related morbidities or deaths.

Conclusions
Arachnoid cysts are a relatively benign pathological entity that can be managed by performing endoscopically guided cyst wall fenestrations into the ventricular system or cerebrospinal fluid–containing cisterns. Proper patient selection, preoperative planning of endoscope trajectory, use of frameless navigation, and advances in endoscope lens technology and light intensity combine to make this a safe procedure with excellent outcomes.
A novel minimally invasive presacral approach and instrumentation technique for anterior L5–S1 intervertebral discectomy and fusion
Authors: Marotta Nicola , Cosar Murat , Pimenta Luiz , Khoo Larry T. 
Published: January 2008

Object
The authors describe a new paracoccygeal approach to the L5–S1 junction for interbody fusion with transsacral instrumentation. The purpose of this technical note is to demonstrate a novel surgical approach, technique, and instrumentation system for the treatment of L5–S1 instability in degenerative disc disease and spondylolisthesis.

Methods
This technical note highlights the AxiaLif (TranS1) transsacral system as an alternative method to transforaminal lumbar interbody fusion or posterior lumbar interbody fusion. Via a novel presacral approach corridor, a truly percutaneous L5–S1 discectomy, interbody distraction, and fixation are achieved, and retroperitoneal viscera and dorsal neural elements are avoided. Percutaneous pedicle screw fixation is then used to provide additional stabilization at the treated level.

Conclusions
This novel technique of interbody distraction and fusion via a truly percutaneous approach corridor allows for circumferential treatment of the lower lumbar segments with minimal risk to the anterior organs and dorsal neural elements.
Pediatric subaxial cervical spine injuries: origins, management, and outcome in 51 patients
Authors: Dogan Seref , Safavi-Abbasi Sam , Theodore Nicholas , Horn Eric , Rekate Harold L. , Sonntag Volker K. H. 
Published: January 2008

Object
In this study the authors evaluated the mechanisms and patterns of injury and the factors affecting management and outcome of pediatric subaxial cervical spine injuries (C3–7).

Methods
Fifty-one pediatric patients (38 boys and 13 girls; mean age 12.4 years, range 10 months–16 years) with subaxial cervical spine injuries were reviewed retrospectively. Motor vehicle accidents (MVAs) were the most common cause of injury. Overall, 12% presented with a dislocation, 63% with a fracture, 19% with a fracture–dislocation, and 6% with a ligamentous injury. The most frequently injured level was C6–7 (33%); C3–4 (6%) was least frequently involved. Sixty-four percent of patients were neurologically intact, 16% had incomplete spinal cord injuries (SCIs), 14% had complete SCIs, and three patients (6%) died after admission and before assessment. Treatment was conservative in 64%: seven (13%) wore a halo vest and 26 (51%) wore a rigid cervical orthosis. Surgery was performed in the other 18 patients (36%), with the breakdown as follows: 15 (30%) underwent an anterior approach, two (4%) had posterior approaches, and one (2%) had a combined approach. Postoperatively, four patients (8%) who had a neurological deficit improved. The overall mortality rate was 8%; all deaths were related to MVAs. There were no surgery-related deaths or complications.

Conclusions
Subaxial cervical spine injuries are common in children 9 to 16 years of age, and occur principally between C-5 and C-7. Multilevel injury is more common in children 8 years of age and older than in younger children and infants. Most patients with subaxial cervical spine injuries can be treated conservatively. Both anterior and posterior approaches are safe and effective.
Cervical epidural hematoma in children: a rare clinical entity
Authors: Fountas Kostas N. , Kapsalaki Eftychia Z. , Robinson Joe Sam 
Published: January 2008

✓ Pediatric spinal epidural hematoma is a very rare clinicopathological entity. In the vast majority of cases, spinal epidural hematomas have a nonspecific clinical presentation; this, along with their rapid progression, makes their early diagnosis and prompt surgical evacuation critical. Magnetic resonance imaging is the neuroimaging modality of choice, whereas hemilaminectomy or laminectomy is the indicated surgical intervention. The outcome is good when hematoma evacuation is performed before the onset of complete sensorimotor paralysis.
In this communication, the authors describe a 12-year-old girl with a traumatic acute cervical epidural hematoma. This lesion was successfully evacuated through a hemilaminectomy, and the patient had an excellent outcome. The pertinent literature is reviewed in terms of the incidence, origin, management, and prognosis of this rare and potentially disastrous clinical entity.