bluuebunny/crossref_metadata_2025 huggingface dataset:
NF2 and Spinal Tumors
Authors: Parry Dilys M.
Published: January 2008

Object

The authors conducted a study to examine the incidence, classification, and progression of spinal tumors in patients with neu-rofibromatosis Type 2 (NF2) treated at a single center, and to examine relationships with the known mutational subtypes of NF2.

Methods

They performed a retrospective review of clinical records, neuroimaging studies, and genetic data obtained in 61 patients with NF2.

Forty-one (67%) of 61 patients harbored one or more spinal tumors. Thirty-four patients had undergone serial spinal magnetic resonance imaging during a mean follow-up period of 52 months (range 10–103 months; median 53 months). In 16 patients there were multiple extramedullary tumors smaller than 5 mm, which did not progress. Fourteen patients harbored at least one extramedullary tumor that was greater than 5 mm; of these, radiological progression was demonstrated or spinal tumor excision was performed during the follow-up period in eight cases (57%). Eleven patients harbored intramedullary cord tumors in addition to small and large extramedullary tumors, three (27%) of which exhibited radiological progression. In cases in which genotypes were known, protein-truncating mutations were significantly more likely to be associated with the presence of spinal tumors than in other types (p = 0.03, Fisher exact test). No associations between clinical behavior of spinal tumors and genotype, however, could be demonstrated.

Conclusions

Spinal tumors in cases involving NF2 are heterogeneous in type, distribution, and behavior but larger-size tumors are more likely to progress significantly. Intramedullary tumors usually accompany multiple extramedullary tumors. In the authors' experience subtyping of the NF2 mutation has not yet influenced management. Protein-truncating mutations are associated with an increased prevalence of spinal tumors.
Failure modes of spinal cord stimulation hardware
Authors: Rosenow Joshua M. , Stanton-Hicks Michael , Rezai Ali R. , Henderson Jaimie M.
Published: January 2008

Object

Epidural spinal cord stimulation (SCS) is effective at treating refractory pain. The failure modes of the implanted hardware, however, have not been well studied. A better understanding of this could aid in improving the current procedure or designing future devices.

Methods

The authors reviewed electronic charts and operative reports of 289 patients who had undergone SCS implantation between 1998 and 2002 at the Cleveland Clinic Foundation. Data were collected on demographics, type of hardware, date of implantation procedure, indication for treatment, time to failure, and failure mode. Data were then analyzed to identify significant differences.

A total of 577 procedures were performed, 43.5% of which involved revision or removal of SCS hardware. The most common indication was complex regional pain syndrome 1, and this was followed by failed–back surgery syndrome. The median number of procedures per patient was two. Approximately 80% of all leads were the percutaneous type. The majority (62%) of leads were placed in the thoracic region, and 33.5% of all leads required revision. Poor pain relief coverage was the most common indication for revision. Surgically implanted leads broke twice as often as percutaneous leads. In 46% of the patients, hardware revision was required, and multiple revisions were necessary in 22.5%. Three-way ANOVA revealed significant differences in failure mode rates according to location (cervical compared with thoracic, p = 0.037) and failure modes (p = 0.019). Laminotomy leads tended to break and migrate sooner than percutaneous leads. Thoracic leads became infected sooner than cervical leads.

Conclusions

The results of this analysis of SCS hardware failures may be used as a basis for refining surgical technique and designing the next generation of SCS hardware.
Complications of spinal cord stimulation, suggestions to improve outcome, and financial impact
Authors: Kumar Krishna , Wilson Jefferson R. , Taylor Rod S. , Gupta Shivani
Published: January 2008

Object

The long-term success of spinal cord stimulation is impeded by the high incidence of adverse events. The cost of complications to the healthcare budget is influenced by the time course needed to reverse the effect, and by the type of corrective measures required. Understanding the mechanism of complications and reducing them can improve the overall success rate and the cost factor.

Methods

The authors performed a retrospective analysis of data obtained in 160 patients treated during a 10-year period. For each category of complication, the level of healthcare resource use was assessed for each case and a unit cost was applied. The total cost of each complication was determined by summing across healthcare resource headings. All cost calculations were performed in Canadian dollars at 2005 prices.

To understand the mechanics of various hardware-related complications and how to avoid them, the authors have utilized the results of bench tests conducted at Medtronic, Inc.

Fifty-one adverse events occurred in 42 of the 160 patients. The complications were classified as either hardware related (39 events) or biological (12 events). The mean cost of complications during the 10-year study period was $7092 (range $130–$22,406).

Conclusions

Complications not only disrupt the effect of pain control but also pose an added expense to the already high cost of therapy. It is possible to reduce the complication rate, and thus improve the long-term success rate, by following the suggestions made in this paper, which are supported by the biomechanics of the human body and the implanted material.
Detected and overlooked cervical spine injury in comatose victims of trauma: report from the Pennsylvania Trauma Outcomes Study
Authors: Piatt Joseph H.
Published: January 2008

Object

This study was undertaken to determine whether a clinically useful rule could be formulated for identifying the presence of traumatic brain injury (TBI) in patients who are at exceptionally low risk of cervical spine injury.

Methods

The Pennsylvania Trauma Outcomes Study database was searched for cases of TBI in which the admission Glasgow Coma Scale (GCS) score was less than or equal to 8. Cases of cervical injury were identified based on diagnostic codes. Associations between cervical injury and various clinical variables were tested using chi-square analysis. The probability of cervical injury was modeled using logistic regression. Decision tree models were constructed. Statistical determinants of overlooked cervical injury were examined.

The prevalence of cervical injury among 41,142 cases of TBI was 8%. Mechanism of injury, thoracolumbosacral (TLS) fracture, age, limb fracture, admission GCS score, hypotension, and facial fracture were associated with cervical injury and were incorporated into the following logistic regression model: probability = 1 / (1 + exp[4.248 − 0.417 × mechanism −0.264 ×age −0.678 ×TLS −0.299 ×limb −0.218 ×GCS −0.231 ×hypotension −0.157 ×facial]).

The results of applying this model provided a rule for cervical spine clearance applicable to 28% of the cases with a negative predictive value (NPV) of 97.0%. Decision tree analysis yielded a rule applicable to 24% of the cases with an NPV of 98.2%. The prevalence of overlooked cervical injury in all individuals with severe TBI was 0.3%; the prevalence of overlooked cervical injury in patients with cervical injury was 3.9%. Overlooked cervical injury was less common in patients with associated TLS fractures (odds ratio 0.453, 95% confidence interval 0.245–0.837).

Conclusions

This analysis identified no acceptable rule to justify relaxing vigilance in the search for cervical injury in patients with severe TBI. Provider vigilance and consequent rates of overlooked cervical injury can be affected by environmental cues and presumably by other behavioral and organizational factors.
Predictive factors for dural tear and cerebrospinal fluid leakage in patients undergoing lumbar surgery
Authors: Sin Anthony H. , Caldito Gloria , Smith Donald , Rashidi Mahmoud , Willis Brian , Nanda Anil
Published: January 2008

Object

A dural tear resulting in a cerebrospinal fluid (CSF) leak is a well-known risk of lumbar spinal procedures. The authors hypothesized that the incidence of CSF leakage is higher in cases involving repeated operations and those in which the surgeon performing the surgery is less experienced; however, they postulated that the overall outcome of the patient would not be adversely affected by a dural tear.

Methods

An institutional review board–approved protocol at Louisiana State University Health Sciences Center, Shreveport, was initiated in August 2003 to allow prospective comparison of data obtained in patients in whom a CSF leak occurred (Group A) and those in whom no CSF leak occurred (Group B) during lumbar surgery. Basic demographic information, descriptive findings regarding the tear, history of other surgeries, hospital length of stay (LOS), and immediate disposition at the time of discharge were compared between the two groups.

Seventy-seven patients were eligible for this study. One patient refused to participate. In 12 (15.8%) of 76 patients CSF leakage developed. In three patients the presence of a tear was questioned, and the patients were clinically treated as if a tear were present. The patients in Group A were older than those in Group B (59.8 ± 16.9 and 49.4 ± 13.6 years of age, respectively; p = 0.02, Fisher exact test). In terms of those with a history of surgery, there was no significant difference between patients with and patients without a CSF leak (three [25%] of 12 patients [Group A] compared with 28 [43.8%] of 64 patients [Group B]; p = 0.34, two-sample t-test). In the 12 patients with dural tears, nine (75%) were caused by a resident-in-training, and the Kerrison punch was the instrument most often being used at the time (55%). This is significantly greater than 50% at the 5% level (p = 0.044, binomial test). The authors were able to repair the tear primarily with suture in all but one patient, whose tear was along the nerve root sleeve. In all cases fibrin glue and a muscle/fat graft were used to cover the tear, and all patients were assigned to bed rest from 24 to 48 hours after the operation. In Group A one patient required rehabilitation at discharge. The LOS in Group A was greater than that in Group B (median 5 days compared with 3 days), but no additional complication was noted.

Conclusions

The incidence of CSF leakage was 16% in 76 patients, and there were no other complications. Older patient age and higher level of the surgeon’s training were factors contributing to the incidence, but the history of surgery was not.
Spinal cord compression from traumatic anterior cervical pseudomeningoceles
Authors: Horn Eric M. , Bristol Ruth E. , Feiz-Erfan Iman , Beres Elisa J. , Bambakidis Nicholas C. , Theodore Nicholas
Published: January 2008

✓Pseudomeningoceles rarely develop after cervical trauma; in all reported cases the lesions have extended outside the spinal canal.

The authors report the first known cases of anterior cervical pseudomeningoceles contained entirely within the spinal canal and causing cord compression and neurological injury. The authors retrospectively reviewed the cases of three patients with traumatic cervical spine injuries and concomitant compressive anterior pseudomeningoceles. The lesion was recognized in the first case when the patient’s neurological status declined after he sustained a severe atlantoaxial injury; the pseudomeningocele was identified intraoperatively and decompressed. After the decompressive surgery, the patient’s severe tetraparesis partially resolved. In the other two patients diagnoses of similar pseudomeningoceles were established by magnetic resonance imaging. Both patients were treated conservatively, and their mild to moderate hemiparesis due to the pseudomeningocele-induced compression abated.

The high incidence of anterior cervical pseudomeningoceles seen at the authors’ institution within a relatively brief period suggests that this lesion is not rare. The authors believe that it is important to recognize the compressive nature of these lesions and their potential to cause devastating neurological injury.
Correlation of anomalous vascular and osseous anatomy in congenital kyphosis Type I
Authors: Chwajol Mark , Houten John K.
Published: January 2008

✓Congenital kyphosis Type I results from failure of formation of the vertebral body (VB). The clinical course is characterized by progressive deformity and neurological dysfunction unless the patient undergoes fusion. It has been postulated that failure of VB formation may be secondary to anomalies of the segmental arteries arising from the aorta. There is limited clinical evidence in the literature, however, to support this hypothesis. The authors report on the case of an adult patient with congenital kyphosis Type I in whom spinal angiography correlated vascular with vertebral anomalies.

This 32-year-old man presented with back pain, lower-extremity paresthesias, and incomplete voiding, which had progressed over several years. Imaging revealed that the L-1 and L-2 vertebrae had not fully formed, causing kyphotic deformity such that the anterior portion of T-12 nearly articulated with that of L-3; this anomaly produced significant mobility in flexion and extension. Magnetic resonance imaging revealed distal spinal cord atrophy and signal change on T2-weighted images.

Spinal angiography showed that the right and left segmental arteries at both L-1 and L-2 arose from a common trunk from the aorta. This was confirmed during subsequent T12–L3 anterior–posterior fusion. Postoperatively the patient experienced relief of pain and remained neurologically stable throughout a 3-year follow-up period.

The presence of corresponding anomalies of the segmental arteries and vertebrae in this case of congenital kyphosis Type I indicates that a relationship may exist in the genesis of aberrant spinal vertebral and vascular structures.
Exposure of the V1–V3 segments of the vertebral artery via the posterior cervical triangle: a cadaveric feasibility study
Authors: Tubbs R. Shane , Shoja Mohammadali M. , Acakpo-Satchivi Leslie , Wellons John C. , Blount Jeffrey P. , Oakes W. Jerry , Iskandar Bermans J.
Published: January 2008

Object

Surgical exposure of the extracranial part of the vertebral artery (VA) is occasionally necessary. Historically, the greater portion of the extracranial portion of the VA has been approached by traversing the anterior cervical triangle. The authors speculated that this entire segment of the VA could be reached with equal efficacy via the posterior cervical triangle (PCT).

Methods

Six adult cadavers underwent dissection of the left and right VAs via the PCT. The entire extracranial VA was easily exposed through this approach. Only three of 12 sides required the transection of the clavicular head of the sternocleidomastoid muscle for exposure of the most proximal segment of the VA as it originated from the subclavian artery. No gross injury to the VA or other regional vessels or nerves was noted.

Conclusions

The authors found that the extracranial VA can be exposed easily through the PCT. Following confirmation of this technique in vivo, this approach may be added to the surgeon’s armamentarium for exposing the extracranial segment of the VA.
Endoscopic transoral surgery for craniovertebral junction anomalies
Authors: Husain Mazhar , Rastogi Manu , Ojha Bal Krishna , Chandra Anil , Jha Deepak K.
Published: January 2008

✓Craniovertebral junction (CVJ) anomalies continue to be challenging for neurosurgeons because of the complex anatomy of this region. To date, microsurgical decompression via a transoral route is the standard treatment for anteriorly located compressive lesions of the cervicomedullary junction (CMJ). The results obtained by minimizing surgical trauma are fewer complications, shorter hospital stays, and reduced overall psychological burden. Endoscopic surgery is becoming a leading modality in minimally invasive neurosurgical treatment.

The authors performed surgery in 11 patients with irreducible osseous dislocations resulting from CVJ abnormality during a 2-year period. Anterior CMJ decompression was achieved in all patients by performing neuroendoscopically controlled transoral excision of bone and soft tissues. The surgical technique and results will be discussed. The use of the endoscope offers several advantages in cases requiring a transoral approach to the lower clivus and atlantoaxial region. The use of minimally invasive endoscopic techniques has the potential to reduce the need for a wider cranial base opening and to decrease postoperative complications.
Incidence of unusual and clinically significant histopathological findings in routine discectomy
Authors: Wu Adam S. , Fourney Daryl R.
Published: January 2008

Object

Routine histopathological examination of discectomy specimens remains common practice in many hospitals, although it rarely detects unsuspected clinically significant disease. Controversy exists as to the effectiveness of this practice. The objectives of this study were to compare the authors’ experience with a review of the literature.

Methods

In a retrospective database analysis the authors identified all intervertebral disc specimens obtained during spinal procedures over an 8-year period (1996–2004). Cases of benign (nonneoplastic and noninfectious) indications for surgery were included in the study, whereas cases of nonbenign indications were excluded. The final pathological diagnoses were reviewed, and a chart review was performed to determine whether any unexpected findings affected subsequent patient care. A total of 1858 discectomy specimens were identified: 1775 of these were obtained in 1719 routine discectomy procedures. Unexpected histopathological findings were identified in four cases, and none was clinically significant.

Conclusions

Routine histopathological examination of disc specimens is not justified. The decision to send specimens for pathological examination should be determined on a case-by-case basis after consideration of the clinical presentation, results of laboratory and imaging studies, and intraoperative findings.
Surgical treatment of lumbar epidural varices
Authors: Slin’ko Eugene I. , Al-Qashqish Iyad I.
Published: January 2008

Object

An epidural varix of the lumbar spine is an acquired pathological entity that results from dilation of the internal vertebral venous plexus. The dilated veins in the epidural spaces or in the intervertebral foramen cause irritation or compression of the thecal sac and nerve roots, and this in turn causes lumbar radiculopathy. The lesions develop as an independent process or are accompanied by degenerative changes of the lumbar spine. Resection of varicose veins can be complicated when significant venous bleeding occurs. The purpose of the present study was to develop diagnostic criteria for lumbar epidural varices and methods of surgical treatment and to analyze the results of treatment.

Methods

There were 43 surgically treated patients in whom lumbar radiculopathy was caused by epidural varices. The mean duration of symptoms was 11 months (range 5–49 months) and the mean age of the patients was 41 years (range 26–68 years). Segmentary varices were found in 14 patients, local varices in 21, and extensive varices in eight. Patients underwent preoperative magnetic resonance imaging and vertebral venography.

Of 43 cases, the varicose veins were completely occluded in all 14 patients with segmentary varices of the segmentary-type lesion. Of 21 patients with local varices, total occlusion was obtained in 17 patients and partial occlusion in four. In the patients with extensive varices, total occlusion was not performed; instead, partial occlusion was undertaken.

Resolution of lumbar radicular syndromes was observed, to some extent, in all patients. Radicular pain regressed in 12 of 14 patients with segmentary varices, in 18 of 19 patients with local varices, and in three of four patients with extensive varices. Nerve root–related sensory disturbances regressed in six of 10 patients with segmentary varices, in 11 of 15 patients with local varices, and in one patient with extensive varices. Motor deficits regressed in three of eight patients with segmentary varices, in three of six patients with local varices, and in none among those with extensive varices.

Conclusions

Epidural varicosity is a specific form of spinal disease. Its diagnostic clarification and surgical treatment are difficult and have only recently been developed. Precise diagnosis and a well-planned surgery allow for a positive outcome.
The use of hemopoietic stem cells derived from human umbilical cord blood to promote restoration of spinal cord tissue and recovery of hindlimb function in adult rats
Authors: Nishio Yutaka , Koda Masao , Kamada Takahito , Someya Yukio , Yoshinaga Katsunori , Okada Seiji , Harada Hideki , Okawa Akihiko , Moriya Hideshige , Yamazaki Masashi
Published: January 2008

Object

The use of human umbilical cord blood (HUCB) cells has been reported to improve functional recovery in cases of central nervous system injuries such as stroke, traumatic brain injury, and spinal cord injury (SCI). The authors investigated the effects of hemopoietic stem cells that were derived from HUCB and transplanted into the injured spinal cords of rats.

Methods

One week after injury, an HUCB fraction enriched in CD34-positive cells was transplanted into the experimental group. In control animals, vehicle (Matrigel) was transplanted. Recovery of motor functions was assessed using the Basso, Beattie, and Bresnahan Locomotor Scale, and immunohistochemical examinations were performed.

Cells from HUCB that were CD34 positive improved functional recovery, reduced the area of the cystic cavity at the site of injury, increased the volume of residual white matter, and promoted the regeneration or sparing of axons in the injured spinal cord. Immunohistochemical examination revealed that transplanted CD34-positive cells survived in the host spinal cord for at least 3 weeks after transplantation but had disappeared by 5 weeks. The transplanted cells were not positive for neural markers, but they were positive for hemopoietic markers. There was no evidence of an immune reaction at the site of injury in either group.

Conclusions

These results suggest that transplantation of a CD34-positive fraction from HUCB may have therapeutic effects for SCI. The results of this study provide important preclinical data regarding HUCB stem cell–based therapy for SCI.
Type A intradural spinal arteriovenous fistula
Authors: Mitha Alim P. , Murphy Erin E. , Ogilvy Christopher S.
Published: January 2008

✓ In this report, the authors present the case of a patient with a unique type of spinal arteriovenous fistula. Both the location and venous angioarchitecture of this variant are uncommon, making diagnosis of the lesion challenging and raising particular management issues. The authors discuss this unusual lesion and describe its imaging features and surgical findings, as well as highlight its pathological abnormalities.
Complete removal of an intraspinal and extraspinal cervical chordoma in one stage using the lateral approach
Authors: Barrey Cédric , Saint-Pierre Ghislaine , Frappaz Didier , Hermier Marc , Mottolese Carmine
Published: January 2008

✓The authors describe a precise surgical technique in which a large intraspinal and extraspinal, multivertebral, cervical chordoma was completely removed in one stage using the lateral approach.

The patient in this case was a 29-year-old woman who presented with signs of radicular pain in the left C-3 area. Computed tomography and magnetic resonance imaging demonstrated a large intra- and extraspinal multivertebral tumor from C-2 to C-5, a finding that suggested a cervical chordoma. The tumor was completely removed in one stage using the lateral approach while controlling the vertebral artery (VA), and a partial corporectomy of C2–5 was also performed. Results from a postoperative histopathological examination confirmed that the tumor was a typical chordoma. The patient’s postoperative course was uneventful.

Cervical chordomas are typically excised using a posterior–anterior surgical approach with partial resection of the tumor. The lateral approach was appropriate in this patient for complete resection in one stage, because it enabled the surgeons to control the VA and access both extraspinal and intraspinal components of the chordoma.
Translaminar screw fixation in the upper thoracic spine
Authors: Kretzer Ryan M. , Sciubba Daniel M. , Bagley Carlos A. , Wolinsky Jean-Paul , Gokaslan Ziya L. , Garonzik Ira M.
Published: January 2008

Object

The use of pedicle screws (PSs) for instrument-assisted fusion in the cervical and thoracic spine has increased in recent years, allowing smaller constructs with improved biomechanical stability and repositioning possibilities. In the smaller pedicles of the upper thoracic spine, the placement of PSs can be challenging and may increase the risk of damage to neural structures. As an alternative to PSs, translaminar screws can provide spinal stability, and they may be used when pedicular anatomy precludes successful placement of PSs. The authors describe the technique of translaminar screw placement in the T-1 and T-2 vertebrae.

Methods

Seven patients underwent cervicothoracic fusion to treat trauma, neoplasm, or degenerative disease. Nineteen translaminar screws were placed, 13 at T-1 and six at T-2. A single asymptomatic T-2 screw violated the ventral laminar cortex and was removed.

The mean clinical and radiographic follow up exceeded 14 months, at which time there were no cases of screw pull-out, screw fracture, or progressive kyphotic deformity.

Conclusions

Rigid fixation with translaminar screws offers an attractive alternative to PS fixation, allowing the creation of sound spinal constructs and minimizing potential neurological morbidity. Their use requires intact posterior elements, and care should be taken to avoid violation of the ventral laminar wall.
Pseudoglandular schwannoma of the cauda equina
Authors: Ruggeri Francesco , De Cerchio Leonardo , Bakacs Arianna , Orlandi Augusto , Lunardi Pierpaolo
Published: January 2008

✓The authors present a case of pseudoglandular schwannoma with immunohistochemical findings consistent with epithelial metaplasia. Pseudoglandular schwannoma is a rare morphological variant of benign schwannoma characterized by the presence of glandlike structures lined with Schwann cells. To the best of the authors’ knowledge, this is only the fifth case of pseudoglandular schwannoma reported in the literature. Clinical, imaging, and pathological findings are described. The pathological findings were consistent with a pseudoglandular schwannoma composed of typical Schwann cells arranged in an Antoni B pattern, with numerous large pseudocystic spaces. Serial immunohistochemical studies of tissue sections revealed that the cells lining the pseudoglandular spaces were not only diffusely reactive for S100 protein, but also demonstrated focal positivity for epithelial membrane antigen and cytokeratins AE1 and AE3. The particular immunohistochemical features of incompletely differentiated Schwann cells in the present case give support to the metaplastic theory of the origin of glandlike structures in benign peripheral nerve sheath tumors.
Trombone tongue: a new clinical sign for significant medullary compression at the craniovertebral junction
Authors: Lee Cheong H. , Casey Adrian T. H. , Allibone James B. , Chelvarajah Ramesh
Published: January 2008

✓The authors describe a previously unreported clinical sign that may indicate the onset of significant compression of the medulla oblongata in cases of craniovertebral junction abnormalities. This 17-year-old boy presented with mild bilateral leg weakness. Imaging studies revealed severe basilar invagination and a marked Chiari malformation. While awaiting surgery, his tongue developed an involuntary constant protrusion–intrusion repetitive motion. The onset of this so-named “trombone tongue” sign was followed shortly afterward by rapidly progressive spastic tetraparesis. After the authors performed a transmaxillary clivectomy, foramen magnum decompression, and occipitocervical fusion, they noted that the abnormal tongue motion promptly resolved and the tetraparesis gradually improved.

The authors discuss their current understanding of the central control of tongue movements and present a hypothesis on the pathogenesis of trombone tongue based on the neuroanatomical basis of another abnormal tongue movement sign, lingual myoclonus.
An extramedullary plasmacytoma originating from the thoracic spinal cord: magnetic resonance imaging findings
Authors: Gao Bo , Wang Xuejian
Published: January 2008

✓Extramedullary plasmacytoma (EMP) is a rare tumor. The authors report a case of an EMP originating in the thoracic spinal cord. To their knowledge this is the first report in which an EMP originating in this location is described. Isointense and hyperintense signals were seen on T1-weighted and T2-weighted magnetic resonance images, respectively, with marked irregular contrast enhancement and extensive edema. No evidence of bone marrow involvement or multiple myeloma was noted. The histological findings were compatible with an EMP.
Ventriculoperitoneal shunt failure causing myelopathy in a patient with bilateral jugular vein occlusion
Authors: Humphries William E. , Grossi Peter M. , Liethe Linda G. , George Timothy M.
Published: January 2008

✓The authors describe the case of a 36-year-old woman with bilateral internal jugular vein occlusion, hydrocephalus, and Dandy–Walker variant who presented with myelopathy that was ultimately attributed to ventriculoperitoneal (VP) shunt failure. Computed tomography (CT) angiography of the head and neck revealed epidural venous engorgement within the cervical spine, greater that 50% narrowing of the C2–5 spinal canal, and compression of the cervical spinal cord. After successful shunt revision, postoperative CT angiography revealed decreased venous engorgement as well as decompression of the cervical spinal cord, and the patient’s myelopathy improved. This case represents a fascinating clinical presentation of VP shunt failure, highlighting the physiological importance of the external jugular pathways involved in cerebral venous drainage.
Spontaneous regression of a discal cyst
Authors: Chou Dean , Smith Justin S. , Chin Cynthia T.
Published: January 2008

✓The authors describe a case of a discal cyst that resolved almost completely without direct intervention. Discal cysts are rare, with the authors of only a few case reports describing this entity. These reports all identify at least some intervention performed for alleviation of the symptoms, including open surgery, minimally invasive surgery, or percutaneous puncture with aspiration. The authors report on a 35-year-old man with radiculopathy who presented with a discal cyst and was treated with a routine epidural injection and selective nerve root block. Within 5 months, the discal cyst showed dramatic regression on magnetic resonance imaging and the patient’s symptoms improved. The natural history of this pathological entity is unknown, and to the authors’ knowledge this is the first detailed report of the regression of a discal cyst without surgery or aspiration.
Survivors of occipitoatlantal dislocation injuries: imaging and clinical correlates
Authors: Horn Eric M. , Feiz-Erfan Iman , Lekovic Gregory P. , Dickman Curtis A. , Sonntag Volker K. H. , Theodore Nicholas
Published: January 2008

Object

Although rare, traumatic occipitoatlantal dislocation (OAD) injuries are associated with a high mortality rate. The authors evaluated the imaging and clinical factors that determined treatment and were predictive of outcomes, respectively, in survivors of this injury.

Methods

The medical records and imaging studies obtained in 33 patients with OAD were reviewed retrospectively. Clinical factors that predicted outcomes, especially neurological injury at presentation and imaging findings, were evaluated.

The most sensitive method for the diagnosis of OAD was the measurement of basion axial–basion dens interval on computed tomography (CT) scanning. Five patients with severe traumatic brain injuries (TBIs) were not treated and subsequently died. Of the 28 patients in whom treatment was performed, 23 underwent fusion and five were fitted with an external orthosis. Abnormal findings of the occipitoatlantal ligaments on magnetic resonance (MR) imaging, associated with no or questionable abnormalities on CT scanning, provided the rationale for nonoperative treatment. Of the 28 patients treated for their injuries, perioperative death occurred in five, three of whom had presented with severe neurological injuries. The mortality rate was highest in patients with a TBI at presentation. The mortality rate was lower in patients presenting with a spinal cord injury, but in this group there was a higher rate of persistent neurological deficits.

Conclusions

The spines in patients with CT-documented OAD are most likely unstable and need surgical fixation. In patients for whom CT findings are normal and MR imaging findings suggest marginal abnormalities, nonoperative treatment should be considered. The best predictors of outcome were severe brain or upper cervical injuries at initial presentation.
Serum creatine phosphokinase activity and histological changes in the multifidus muscle: a prospective randomized controlled comparative study of discectomy with or without retraction
Authors: Kotil Kadir , Tunckale Tamer , Tatar Zeynep , Koldas Macit , Kural Alev , Bilge Turgay
Published: January 2008

Object

The aim of this study was to determine the extent of muscle injury caused by continuous or intermittent muscle retraction during macro- and microdiscectomy in lumbar disc surgery. Pain scores, serum creatine phosphokinase (CPK) levels, and histological findings obtained in muscle specimens were compared.

Methods

Sixty patients who underwent surgery for a one-level disc herniation during a 1-year period (January 2004–January 2005) and who had similar demographic characteristics were randomly assigned to one of four groups, each consisting of 15 patients: Group A, microdiscectomy in which the retractor was never released; Group B, microdiscectomy in which the retractor was released every 15 minutes; Group C, macrodiscectomy in which the retractor was never released; and Group D, macrodiscectomy in which the retractor was released every 15 minutes.

Muscle biopsy samples were acquired in each group, and biochemical studies were conducted to determine serum CPK levels. The duration of muscle retraction was 15 minutes followed by 3 minutes of relaxation in Groups B and D. In all groups, muscle degeneration and elevation in serum CPK levels were observed immediately after surgery. The overall results, however, were different. The decline of serum CPK levels started 1 week after surgery. The smallest degree of muscle injury (reflected by the lowest serum CPK level) was observed in Group B. When the pre- and postoperative CPK values were compared in all groups, the patients in Groups B and D reported the least amount of back pain (p < 0.001). No significant differences in serum CPK levels were observed between Groups A and C or between Groups B and D. The extent of back pain was evaluated using a visual analog scale, and the consumption of analgesics was also assessed. The groups exhibited significantly different responses: the lowest analgesic consumption and the lowest pain scores were demonstrated in Groups B and D.

Conclusions

In this prospective randomized clinical trial, the authors determined that muscle injury during lumbar disc surgery was closely related to muscle retraction and relaxation times whereas the size of the paravertebral skin incision had no effect on postoperative back pain and disability. There was no significant difference among the groups in terms of back pain during the long-term follow-up period (18–19 months).
Intraoperative electromyography monitoring in minimally invasive transforaminal lumbar interbody fusion
Authors: Bindal Rajesh K. , Ghosh Subrata
Published: January 2008

Object

Minimally invasive transforaminal lumbar interbody fusion (TLIF) is an increasingly popular method for achieving lumbar decompression and fusion. The procedure is technically more demanding than open fusion, with correspondingly more theoretical risk of complication. The authors describe the use of intraoperative electromyography (EMG) as an adjunct to surgery to reduce the risk of complications.

Methods

Between August 2005 and April 2006, 25 consecutive patients underwent minimally invasive TLIF in which a total of 105 pedicle screws were placed. Intraoperative EMG was performed and included passive recordings during decompression and interbody graft placement, as well as active recording during the placement of the pedicle access needle and testing of the pedicle tap. A uniform protocol for active monitoring was used, with the pedicle access needle set at 7 mA. To assess hardware placement, all patients underwent postoperative radiography and 20 underwent postoperative computed tomography (CT) scanning.

In no patient did the authors observe significant EMG activation during decompression. In five cases, intermittent nerve root firing was noted after the interbody graft was placed, but this did not correlate with any postoperative deficits. Using the active stimulation protocol, 76.2% of screw placements required one or more changes to the trajectory of the pedicle access needle. With successful placement of the pedicle access needle, in all 105 screws, the pedicle tap nerve root stimulation threshold was greater than 15 mA. Postoperative radiography was performed in all patients and CT scanning was performed in 20 patients (with 85 screws being placed). Postoperative imaging revealed only three cases of pedicle breach. In all cases, the breach was at the lateral wall of the pedicle and not thought to be clinically relevant.

Conclusions

A continuous stimulation pedicle access needle alerts the surgeon to incorrect medial trajectories and may lead to safer pedicle cannulation. As a result of electrophysiological feedback, the pedicle access needle trajectory was altered in 76.2% of the reported cases. The use of the authors’ protocol resulted in a 0% incidence of clinically relevant malpositioned hardware and a low overall neurological complication rate. Intraoperative nerve root monitoring is a useful adjunct to minimally invasive TLIF.
Rotational dislocation of the thoracolumbar spine
Authors: Debnath Ujjwal K. , Maripuri Subramanyam Naidu , Mobini Bahram , Etemadifar Mohamed R. , Hossein Mehdian Syed M.
Published: January 2008

✓ The authors report a rare case of rotational dislocation of the thoracolumbar spine in a 12-year-old girl with neurofibromatosis Type 1. The patient had progressive spinal kyphoscoliosis with acute-onset paraplegia. She was treated with corrective traction preoperatively, followed by spinal decompression and circumferential spinal fusion without instrumentation. She had complete neurological recovery after a solid fusion of her spine.
Cervical myelopathy caused by dropped head syndrome
Authors: Nakanishi Kinya , Taneda Mamoru , Sumii Toshihisa , Yabuuchi Tomonari , Iwakura Norihiro
Published: January 2008

✓The authors present a rare case of cervical myelopathy caused by dropped head syndrome. This 68-year-old woman presented with her head hanging forward. After 1 month, she was admitted to the medical service because of head drop progression. Examination of biopsy specimens from her cervical paraspinal muscles showed nonspecific myopathic features without inflammation, and isolated neck extensor myopathy was diagnosed. The patient’s condition did not respond to the administration of corticosteroids. During follow up as an outpatient, the patient’s head drop continued to gradually progress. At 1 year after onset, she developed bilateral weakness of the upper and lower extremities, clumsiness of the hands, and gait disturbance. A radiograph of the cervical spine obtained in a standing position showed a pronounced kyphotic deformity and instability at the level of C4–5. Magnetic resonance imaging demonstrated spinal cord compression at C-3 and C-4. The patient underwent a C3–4 laminectomy and occipitocervicothoracic fixation. Gait and hand coordination gradually improved, and she was able to walk with no support 1 month postoperatively. Surgical fixation was beneficial in this patient with dropped head syndrome, myelopathy, and cervical instability.
En plaque intradural extramedullary spinal tuberculoma and concurrent intracranial tuberculomas: paradoxical response to antituberculous therapy
Authors: Muthukumar Natarajan , Sureshkumar Venkatachalam , Ramesh Vengalathur Ganesan
Published: January 2008

✓Spinal intradural extramedullary tuberculoma is a rare entity. Rarer still are extensive en plaque intradural extramedullary tuberculomas occurring concurrently with multiple intracranial tuberculomas as a paradoxical response to chemotherapy for tuberculosis (TB). The authors describe the case of a 21-year-old man who was treated for tuberculous meningitis. Three months after the episode of meningitis, while undergoing chemotherapy for TB, he developed features of thoracic myelopathy. Investigations revealed an extensive en plaque intradural extramedullary lesion spanning seven segments in the lower thoracic spine. Magnetic resonance imaging of the brain revealed multiple asymptomatic intracranial tuberculomas. Even after further treatment with antituberculous chemotherapy was initiated, the lesion failed to respond. The authors performed a laminectomy and excised the en plaque intradural extramedullary lesion. The patient’s condition responded well to this treatment.

Although the appearance of intracranial tuberculoma as a paradoxical response to chemotherapy has been previously reported, no authors have reported on the development of an extensive en plaque intradural extramedullary tuberculoma in conjunction with asymptomatic multiple intracranial tuberculomas as a paradoxical response.

In cases in which patients present with compressive myelopathy following therapy for tuberculous meningitis, it is important to consider in the differential diagnosis that intradural extramedullary tuberculoma may be a paradoxical response to chemotherapy. The authors’ experience and their review of the literature indicate that surgery has a definitive role to play in the management of spinal intradural extramedullary tuberculoma.
Leiomyosarcoma metastases to the spine
Authors: Elhammady Mohamed Samy A. , Manzano Glen R. , Lebwohl Nathan , Levi Allan D.
Published: January 2008

✓Leiomyosarcoma is a rare malignant smooth-muscle tumor that rarely metastasizes to bone. It is extremely uncommon for osseous metastasis to be the initial presentation of leiomyosarcoma or to be the initial manifestation of recurrence in patients with a history of leiomyosarcoma. The authors have treated four cases of metastatic leiomyosarcoma with the lesion initially presenting in the spine, and a fifth case of disseminated leiomyosarcoma that involved the spine. In their report, they highlight the cases of two of these patients and provide tabular data for the remaining three.

The authors performed a comprehensive review of the literature on spinal leiomyosarcomas and retrospective chart reviews of five surgically treated patients in whom a spinal metastatic leiomyosarcoma was diagnosed.

Their series consists of five women who ranged in age from 36 to 47 years (mean age 43.2 years). Four patients had known, or presumed, uterine primary lesions, whereas one harbored a retroperitoneal primary tumor. These lesions generally appear as lytic foci on imaging studies, but variable imaging characteristics were observed. All cases were managed aggressively: four patients underwent posterior/posterolateral decompression and fusion, and one underwent anterior–posterior en bloc resection and fusion. In all cases preoperative symptoms resolved. Two patients died 9 and 13 years after initial presentation. The remaining patients are alive and neurologically intact.

Metastatic spinal leiomyosarcomas tend to symptomatically involve only one spinal level at the time of diagnosis and are known to recur locally. These lesions commonly affect women in early middle age, and long-term survival, even in those with systemic metastatic lesions, is better than that seen in individuals with more aggressive spinal metastases. Attempted gross-total resection with fusion, as opposed to minimal palliative decompression, is recommended.
Cyclooxygenase-2 expression in ependymoma of the spinal cord
Authors: Naruse Takahiro , Matsuyama Yukihiro , Ishiguro Naoki
Published: January 2008

Object

Cyclooxygenase-2 (COX-2), also known as prostaglandin endoperoxide synthase, has been reported to play an important role in the tumorigenicity of many types of tumors. The expression of COX-2 in spinal ependymomas, however, has not been studied. The authors evaluated COX-2 expression in ependymoma of the spinal cord.

Methods

Sixteen ependymoma samples obtained in patients undergoing surgery between 1995 and 2004 were utilized for immunohistochemical studies to evaluate COX-2 and vascular endothelial growth factor (VEGF) expression. Intratumoral microvessels were also stained immunohistochemically using anti–human von Willebrand factor antibody and were quantified to determine the microvessel density (MVD). The clinical features were reviewed and recorded and the association with COX-2 expression was assessed.

Seven (43.8%) of the 16 ependymoma specimens expressed COX-2. All three of the myxopapillary-type ependymomas exhibited COX-2–positive staining. Excluding the three myxopapillary-type cases, COX-2 expression was identified in four (30.8%) of 13 cellular-type ependymomas. The COX-2–positive samples exhibited a significant increase in VEGF-positive staining cells and MVD compared with COX-2-negative samples. The clinical features were not associated with COX-2 expression.

Conclusions

The results of the present study indicate that COX-2 expression may promote angiogenesis through VEGF expression in ependymomas of the spinal cord. It is suggested that the use of selective COX-2 inhibitors may provide a new therapeutic strategy for spinal cord ependymomas due to their inhibition of the COX-2-mediated angiogenesis.