bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intramedullary Clear Cell Ependymoma in the Cervical Spinal Cord: Case Report
Authors: Akutsu Hiroyoshi , Shibata Yasushi , Okazaki Masao , Hyodo Akio , Matsumura Akira 
Published: September 2004

ABSTRACT

OBJECTIVE AND IMPORTANCE
Clear cell ependymoma of the spinal cord has not been reported in the literature, although ependymoma in the cerebral and cerebellar hemispheres has been described. We present the first case report of this rare histological type of ependymoma arising in the cervical spinal cord and emphasize the importance of recognizing this histological entity.

CLINICAL PRESENTATION
A 42-year-old woman presented with numbness in both upper limbs and spastic gait. Magnetic resonance imaging revealed an intramedullary tumor at the C6–T1 level with syringomyelia.

INTERVENTION
The tumor was totally removed. Histological analysis revealed that the tumor was composed of round cells with perinuclear halos similar to those observed in oligodendroglioma. However, we diagnosed clear cell ependymoma because these tumor cells exhibited epithelial features and ependymal rosettes under light microscopic examination.

CONCLUSION
Histological diagnosis was crucial to our determining whether to perform postoperative adjuvant therapy in this patient. Neurosurgeons should be aware of the possibility of this histological entity among intramedullary spinal cord tumors.
Congenital Absence of a Cervical Pedicle: Report of Two Cases and Review of the Literature
Authors: Sheehan Jason , Kaptain George , Sheehan Jonas , Jane John 
Published: September 2004

ABSTRACTOBJECTIVE AND IMPORTANCEThe congenital absence of a cervical pedicle is a rare clinical entity. Patients with this anomaly tend to present with cervical pain or after a traumatic incident. Initial evaluations with conventional radiography frequently lead to misinterpretation and misguided intervention. We report two cases of absent cervical pedicles and describe the presentation, diagnosis, and treatment of these patients. Moreover, we review the literature on this clinical entity.CLINICAL PRESENTATIONThe first patient was a 4-year-old boy who presented with neck pain after falling off a trampoline. His neurological examination did not reveal any focal abnormalities, but radiographs were thought to be consistent with a right, C4–C5, unilateral, jumped facet. The second patient was a 27-year-old woman who presented with severe neck, back, and left upper extremity pain and paresthesias after an alleged incident of spousal abuse. Her neurological examination results were remarkable for left upper extremity weakness and hemibody sensory changes. Conventional radiographs were thought to reveal a left, C3–C4, unilateral, locked facet.INTERVENTIONFor both patients, reduction attempts were made with Gardner-Wells tongs and traction. After failure to achieve adequate reduction, evaluations using two-dimensional computed tomography confirmed congenitally absent cervical pedicles. Both patients were ultimately treated conservatively and experienced resolution of their presenting symptoms.CONCLUSIONThe congenital absence of a cervical pedicle is a rare entity that is frequently misdiagnosed. Diagnoses can be accurately confirmed with two-dimensional computed tomography. Conservative treatment resulted in successful management of this clinical entity.
Recurrent (Nonfamilial) Hemangioblastomas Involving Spinal Nerve Roots: Case Report
Authors: Raghavan Ravi , Krumerman Jon , Rushing Elisabeth J. , White Charles L. , Chason David P. , Watson Mark L. , Coimbra Caetano 
Published: September 2004

ABSTRACT

OBJECTIVE AND IMPORTANCE
Spinal nerve root hemangioblastomas are rare and are reported mainly in patients with von Hippel-Lindau (VHL) syndrome. The pathogenesis of so-called nonfamilial lesions is virtually unknown. We discuss, mainly from a molecular perspective, a unique patient with sporadic, recurrent hemangioblastomas restricted to spinal nerve roots.

CLINICAL PRESENTATION
A 53-year-old man who had had a surgically corrected lumbosacral meningomyelocele presented on at least three occasions during a 17-year period with multifocal capillary hemangioblastomas involving spinal nerve roots. On each occasion, tumors appeared on a different nerve root, with the majority located in the midcervical segments. The patient had no clinical features or family history of VHL syndrome.

TECHNIQUE
To obtain a clearer understanding of the pathogenesis of this unusual case and its relationship to VHL syndrome, molecular analysis of the VHL gene was performed by use of complete sequence analysis and loss of heterozygosity studies on deoxyribonucleic acid derived from the patient's blood leukocytes and three separately resected hemangioblastomas.

CONCLUSION
Germ-line molecular analysis performed on all three exons in the VHL gene coding region did not indicate that any mutations were present. Loss of heterozygosity analysis of deoxyribonucleic acid from the three hemangioblastoma resections showed normal heterozygosity in the 3p25–26 region. Complete VHL gene sequence analysis did not demonstrate a somatic mutation in the coding region of the VHL gene in any of the three tumors, thereby supporting the loss of heterozygosity data that a molecular event directly involving the VHL gene may not be the causative factor in their tumorigenesis.
Transdural Cauda Equina Incarceration after Microsurgical Lumbar Discectomy: Case Report
Authors: Kothbauer Karl F. , Seiler Rolf W. 
Published: September 2004

ABSTRACT

OBJECTIVE AND IMPORTANCE
Complications usually occur when they are least expected. We present an unusual case of nerve entrapment after microsurgical discectomy.

CLINICAL PRESENTATION
A patient undergoing uneventful first lumbar microsurgical discectomy developed severe back and leg pain and a progressive neurological deficit during the first postoperative night. Herniation of cauda equina nerve roots had occurred through an unnoticed minimal defect in the dura, which had not caused cerebrospinal fluid leakage. The roots were incarcerated and swollen, and they filled the space of the resected nucleus pulposus. It was presumed that elevation of intra-abdominal pressure and consequent increased intraspinal pressure during extubation led to the herniation of arachnoid and cauda equina roots. The nerve roots were then trapped and incarcerated in the manner of bowel loops in an abdominal wall hernia.

INTERVENTION
During reoperation, the nerve roots were repositioned into the dural sac. The patient recovered without further complications and without long-term sequelae.

CONCLUSION
All dural tears that occur during intraspinal surgery, even if they are small and the arachnoid is intact, should be closed with stitches or at a minimum with a patch of muscle or gelatin sponge with fibrin glue. Care should be taken to avoid increased intra-abdominal pressure during extubation. Excessive pain and progressive neurological dysfunction occurring shortly after microsurgical lumbar discectomy or any intraspinal procedure is indicative of possible hemorrhage with subsequent compression of nerve roots. The case reported here provides anecdotal evidence that this situation can also be caused by a herniation of cauda equina nerve roots through a small dural defect that was not evident during the initial operation.
Shoulder Numbness in a Patient with Suprascapular Nerve Entrapment Syndrome: Cutaneous Branch of the Suprascapular Nerve: Case Report
Authors: Harbaugh Kimberly S. , Swenson Rand , Saunders Richard L. 
Published: September 2004

ABSTRACTOBJECTIVE AND IMPORTANCEThe ability to diagnose peripheral nerve disorders is dependent on knowledge of the anatomic course and function of the nerves in question. The classic teaching regarding the suprascapular nerve (SScN) is that it has no cutaneous branches, despite the fact that a cutaneous branch was first reported in the anatomic literature 20 years ago.CLINICAL PRESENTATIONWe describe a case of a 35-year-old male patient who presented with right shoulder pain and atrophy and weakness of the right supra- and infraspinatus muscles. During the examination, he was also noted to have an area of numbness involving the right upper lateral shoulder region. Electrical study results were consistent with SScN entrapment at the suprascapular notch.INTERVENTIONThe patient underwent surgical decompression 7 months after the onset of his symptoms. The patient noted resolution of his shoulder pain immediately after the procedure, and his shoulder sensory disturbance had improved by 2 weeks. At 9 months after surgery, he remained pain-free, his shoulder sensation was normal, and his motor abnormalities had improved significantly.CONCLUSIONThis case provides clinical evidence for the presence of a cutaneous branch of the SScN, as described in cadaveric studies. Although shoulder numbness demands a search for alternative diagnoses, it does not necessarily exclude the diagnosis of SScN entrapment.
Femoral Ring Allograft for Anterior Cervical Interbody Fusion: Technical Note
Authors: Shapiro Scott , Bindal Raj 
Published: September 2004

ABSTRACT

OBJECTIVE
Cadaveric fibula with locking plate internal fixation has been reported to be associated with fewer complications and better long-term results, compared with autologous iliac crest. With the knowledge that cortically dense allografts collapse less with time, new machined femoral ring allografts were developed for anterior cervical fusion after anterior cervical discectomy. We describe the system and the technique for placement.

METHODS
The femoral ring allograft set consists of color-coded graft-sizers that correspond precisely to the size of the precut grafts. The purple set is primarily intended for petite cervical vertebral bodies; the purple sizers and grafts are 11 mm wide and 11 mm deep and vary in height from 5 to 9 mm. The green sizers and grafts are 14 mm wide and 11 mm deep and vary in height from 5 to 11 mm. The blue sizers and grafts are 14 mm wide and 14 mm deep and vary in height from 5 to 11 mm. The rostral and caudal faces of the grafts are corrugated, to improve their holding capacity in the interspace. The bone is sterilely packaged in vacuum-sealed bottles, the tops of which are color-coded and precisely labeled. The set also includes a graft holder (to facilitate insertion into the interspace), impactors, and a barrel-shaped cutting burr (to prepare the endplates for fusion).

RESULTS
After anterior cervical discectomy to treat spondylotic radiculopathy or myelopathy, a femoral ring allograft was inserted, with allogeneic demineralized bone matrix and a locking cervical plate, in 20 cases, with no complications. Use of the system decreased the operating time by an average of 10 to 15 minutes.

CONCLUSION
The femoral ring allograft system is easy to use, and there have been no complications to date. The long-term fusion rate remains to be determined.
Use of Internal Fiducial Markers in Frameless Stereotactic Navigational Systems during Spinal Surgery: Technical Note
Authors: Salehi Sean A. , Ondra Stephen L. 
Published: September 2004

ABSTRACT

OBJECTIVE
The use of frameless stereotaxy has expanded the spine surgeon's ability to perform surgical procedures with instrumentation in areas of narrow anatomic tolerance. In many circumstances, however, it is difficult to register the frameless stereotactic probe using known anatomic landmarks. This occurs typically because landmarks are indistinct, and congenital or surgical defects limit the availability of anatomic fiducials. We propose an accurate and efficient method for registering the frameless stereotactic probe for spinal surgery when a staged procedure is planned.

METHODS
During the first stage of a planned two-stage procedure, a minimum of four cranial fiducial screws are implanted in the posterior element of each vertebra in which stereotactic registration is desired. Stage 1 is completed, and all suture closure is performed. A computed tomographic scan formatted for the frameless stereotactic unit is obtained postoperatively. In the second stage of surgery, registration is performed using cranial screws as internal fiducial markers.

RESULTS
Registration is performed easily and quickly using cranial screws as internal fiducial markers. No more than four registration points are necessary to calibrate the system to accuracy within 1.5 mm.

CONCLUSION
Implantation of fiducial markers during Stage 1 of a complex staged spinal surgery renders the frameless stereotactic navigational system registration extremely fast and accurate. We advocate the technique to enhance the use of frameless navigational systems for reliable and quick registration of the spine.
Convulsive Seizures Following Subdural Application of Fibrin Sealant Containing Tranexamic Acid in a Rat Model
Authors: Schlag Michael G. , Hopf Rudolf , Redl Heinz 
Published: September 2004

ABSTRACTOBJECTIVESTranexamic acid (t-AMCA) has been shown to cause severe convulsions in humans and cats when applied topically to the central nervous system. We wanted to determine whether pure t-AMCA or fibrin sealant (FS) containing t-AMCA would induce similar effects when applied to the spinal cord in a rat model.METHODSFollowing low-thoracic laminectomy, the dura was incised to expose the dorsal surface of the lumbar enlargement. Rats were allocated to one of the following treatments: 1) t-AMCA (10 mg/ml), 2) vehicle (phosphate buffered saline), 3) FS containing t-AMCA, 4) FS containing aprotinin. The response of the rats was evaluated based on neurological and behavioral observations. Additionally, motor function was scored in the rats that had received FS.RESULTSApplication of either 10 mg/ml t-AMCA or FS containing t-AMCA caused severe hind limb spasms that developed into spontaneous generalized convulsions. Two of the three rats that had received FS containing t-AMCA died of respiratory failure. In contrast, application of vehicle or FS containing aprotinin did not cause any abnormal conditions of the animals.CONCLUSIONTranexamic acid may cause severe complications when used in the central nervous system. Thus, fibrin sealants containing t-AMCA should not be used in neurosurgery.
Hemangioblastomas of the Central Nervous System in von Hippel-Lindau Syndrome and Sporadic Disease
Authors: Conway James E. , Chou Dean , Clatterbuck Richard E. , Brem Henry , Long Donlin M. , Rigamonti Daniele 
Published: September 2004

Abstract

OBJECTIVE
The presentation, screening, management, and clinical outcomes of patients who presented to our institution from 1973 to 1999 with central nervous system (CNS) hemangioblastomas in von Hippel-Lindau (VHL) syndrome and sporadic disease were analyzed.

METHODS
The surgical pathology database of our institution was searched to identify all patients with histologically verified CNS hemangioblastomas occurring from 1973 to 1999. The medical, radiological, surgical, pathological, and autopsy records from these patients were reviewed retrospectively and statistically analyzed.

RESULTS
Forty patients (21 males and 19 females) presented with CNS hemangioblastomas. Twenty-five patients (62%) harbored sporadic hemangioblastomas. Fifteen patients (38%) had VHL syndrome. These 40 patients presented with 61 hemangioblastomas (8 patients had multiple lesions). Ten patients (25%) harbored spinal cord hemangioblastomas (5 patients had multiple lesions). Patients with VHL disease tended to present with neurological symptoms and signs at a younger age than patients with sporadic disease (P = 0.09), to present with multiple lesions (53%), and to develop new lesions (rate, 1 lesion/2.1 yr). Hemangioblastomas of the spinal cord were more prevalent in patients with VHL syndrome (P = 0.024). Neuroradiological screening of patients with VHL syndrome allowed identification of more than 75% of new lesions before they became symptomatic. Sixty-six surgical procedures were performed (12 patients required multiple operations). Six patients with VHL syndrome required surgery for new lesions. Surgical complications occurred in six patients (15%). Symptom resolution or arrest of progression at 1 year was documented in 88% of patients. Recurrence of symptoms from partially resected lesions occurred in eight patients (20%). No deaths associated with surgery occurred. One patient with sporadic disease and one patient with VHL syndrome (5%) died as a result of late medical complications from CNS hemangioblastomas.

CONCLUSION
Surgical outcomes for patients with CNS hemangioblastomas are favorable. However, management of hemangioblastomas is a more difficult and prolonged endeavor for patients with VHL syndrome. In patients with VHL syndrome, neuroradiological screening allows identification of lesions before they become symptomatic. Because patients with VHL syndrome are at risk for development of new lesions, they require lifelong follow-up.
Influence of Smoking, Hypertension, and Sex on the Phenotypic Expression of Familial Intracranial Aneurysms in Siblings
Authors: Connolly E. Sander , Choudhri Tanvir F. , Mack William J. , Mocco J , Spinks Theodore J. , Slosberg Jason , Lin Tina , Huang Judy , Solomon Robert A. 
Published: September 2004

Abstract

OBJECTIVE
To investigate the effects of smoking, hypertension, and sex on the phenotypic expression of familial intracranial aneurysms (FIAs).

METHODS
We retrospectively reviewed the case records of 806 consecutive patients undergoing aneurysm surgery at our institution (1986–1995) and discovered 24 families with at least two affected siblings. Prevalence rates for the smoking, hypertension, and sex risk factors in these nuclear families were compared with those of patients with sporadic intracranial aneurysms (SIAs) and population-based control patients.

RESULTS
Affected family members with FIAs exhibited prevalence rates of smoking and hypertension (74% and 43%, respectively) that tended to be higher than those of population-based control patients (52% [P &lt; 0.005] and 36% [P = not significant (NS)], respectively) and comparable to those of patients with SIAs (64% [P = NS] and 40% [P = NS], respectively). A positive association existed between FIA formation and female sex but was somewhat less strong than that observed in the SIAs (59% FIAs, 71% SIAs, 50% control patients). In addition, the prevalence rates of smoking, hypertension, and female sex were higher in affected family members with FIAs than in their unaffected siblings (58% [P &lt; 0.05], 28% [P = 0.06], and 39% [P &lt; 0.05], respectively). Individuals in families with expressed FIAs who had high aneurysmal penetrance had a greater tendency to be smokers, hypertensive, and female (74%, 59%, and 55%, respectively) than did their low-penetrance counterparts (61% [P = 0.1], 27% [P &lt; 0.05], and 45% [P = NS], respectively).

CONCLUSION
Together these data suggest that hypertension, smoking, and female sex increase the likelihood that a member of a family with an expressed FIA will have an aneurysm. These observations may prove helpful in guiding the use of screening studies and encouraging education about the potential risks of continued tobacco use and untreated hypertension in this patient cohort.
Stereotactic Radiosurgery for Motor Cortex Region Arteriovenous Malformations
Authors: Hadjipanayis Constantinos G. , Levy Elad I. , Niranjan Ajay , Firlik Andrew D. , Kondziolka Douglas , Flickinger John C. , Lunsford L. Dade 
Published: September 2004

Abstract

OBJECTIVE
The optimal management of arteriovenous malformations (AVMs) in critical brain locations remains controversial. To reduce the risk of an AVM hemorrhage and to enhance the possibility of preserving neurological function, stereotactic radiosurgery was performed in 33 patients with newly diagnosed or residual AVMs located within the motor cortex. The role of embolization also was examined.

METHODS
During a 9-year study period, 33 patients with AVMs located primarily in the motor cortex region were treated with stereotactic radiosurgery. These patients were followed up radiographically for a minimum of 36 months, or less if obliteration was documented before 36 months had elapsed. Of the 33 patients, 9 underwent embolization and 1 underwent microsurgery before radiosurgery. Nine patients required a second radiosurgery. The mean AVM target volume was 4.35 cc, and the average radiation dose to the AVM margin was 20 Gy. The median follow-up was 36 months (range, 10–91 mo), and angiographic follow-up of eligible patients was performed 24 or 36 months after radiosurgery.

RESULTS
Results were stratified by radiosurgical target volumes: less than 3 cc (Group 1), 3 to 10 cc (Group 2), and greater than 10 cc (Group 3). Overall (including second radiosurgery), 13 (87%) of 15 patients in Group 1 had complete obliteration confirmed by angiography. Nine (64%) of 14 patients in Group 2 exhibited nidus obliteration, and one (25%) of four patients in Group 3 demonstrated obliteration on a magnetic resonance imaging scan. Eight patients (24%) underwent second-stage radiosurgery after angiography revealed a persistent AVM nidus; three patients demonstrated complete obliteration on follow-up angiography. The obliteration rate was higher (87%) for AVMs with less than 3 cc target volume and lower (56%) for those with target volumes larger than 3 cc. One patient experienced worsening neurological function after radiosurgery, and one died from delayed AVM hemorrhage during the latency period. No patient bled after angiographically confirmed AVM obliteration.

CONCLUSION
Stereotactic radiosurgery is a successful and safe management option for patients with motor cortex AVMs. The obliteration of AVMs and the attendant low morbidity rates indicate a primary role for radiosurgery in these patients. Staged radiosurgery may be necessary to increase obliteration rates for larger AVMs or for those that are not obliterated after the first procedure.
Assessment of Alterations in Gene Expression in Recurrent Malignant Glioma after Radiotherapy Using Complementary Deoxyribonucleic Acid Microarrays
Authors: Joki Tatsuhiro , Carroll Rona S. , Dunn Ian F. , Zhang Jianping , Abe Toshiaki , Black Peter McL. 
Published: September 2004

Abstract

OBJECTIVE
We used complementary deoxyribonucleic acid expression microarrays to assess the effects of radiotherapy on gene expression in glioblastoma multiforme. We hypothesized that postradiation recurrent tumors may demonstrate alterations in gene expression from the primary tumor specimen.

METHODS
Patients were diagnosed with glioblastoma multiforme at resection of the initial tumor, and they received 60 Gy of fractionated radiotherapy before recurrence. Ribonucleic acid samples from both the primary and the postradiation recurrent tumor in each patient were screened and compared using complementary deoxyribonucleic acid expression arrays and Northern blot analysis.

RESULTS
Messenger ribonucleic acid levels of growth factors participating in paracrine loops, such as vascular endothelial growth factor and platelet-derived growth factor receptor β, were decreased in postradiation recurrent tumors as compared with primary tumors in three of four patients. However, messenger ribonucleic acid levels of growth factors involved in autocrine loops, such as epidermal growth factor receptor, platelet-derived growth factor α, platelet-derived growth factor A, and basic fibroblast growth factor, were decreased in two of four, two of four, three of four, and three of four patients' recurrent tumors, respectively. Microvessel counts demonstrated that blood vessel growth was decreased significantly in postradiation recurrent tumor specimens.

CONCLUSION
After radiotherapy of glioblastoma multiforme, levels of paracrine-acting growth factors are diminished in correspondence with the reduction in vascular density. In contrast, growth factors that participate in autocrine loops demonstrate elevated levels of gene expression. These results suggest that maintenance of autocrine loops may be important in tumor regrowth after radiotherapy.