bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgical interruption of a midline dorsal column visceral pain pathway
Authors: Nauta Haring J. W. , Hewitt Elena , Westlund Karin N. , Willis William D.
Published: June 2009

✓ A punctate midline myelotomy performed in a patient effectively eliminated residual, intractable pelvic pain, which remained after resolution of uterine cervical cancer. The authors describe the case history of the patient, in whom pain assessments were made, and a surgical procedure performed. Despite large doses of opiate analgesic medications, the patient experienced constant pressure pain in the right lower pelvis, with excruciating pain on bowel movement. Severe weight loss necessitated better pain control. A minimally invasive surgical procedure, a 5-mm deep puncture using a 16-gauge needle on either side of the median septum in the dorsal column of the spinal cord (T-8), resulted in no new neurological deficits. Narcotic medication was tapered, no pain was reported, and the patient resumed daily household activity. Midline myelotomy has typically been performed with the intention of eliminating the crossing fibers of the spinothalamic tract in the anterior white matter commissure. The punctate midline myelotomy described here was performed with the specific intention of interrupting a newly described visceral pain pathway that ascends to higher brain centers through the midline of the dorsal column. The effectiveness of the pain relief seen in this patient suggests that visceral pain of the pelvis in humans may be transmitted in the midline of the dorsal column, as has been recently reported in studies using rats. The effectiveness of the punctate midline myelotomy performed in this one case of pelvic visceral pain suggests that the surgery may eventually be effective in greatly reducing or replacing opiate narcotic medication for visceral pain management.
Subdural sarcoma associated with chronic subdural hematoma
Authors: Cinalli Giuseppe , Zerah Michel , Carteret Michel , Doz François , Vinikoff Laurent , Lellouch-Tubiana Arielle , Husson Beatrice , Pierre-Kahn Alain
Published: June 2009

✓ The authors report the cases of two children who presented in the first months of life with progressive macrocrania related to chronic pericerebral fluid collection. This condition resolved spontaneously without treatment after a few months in the first case, whereas it required several aspirations of blood-stained fluid via the fontanel in the second case. Both patients developed normally without evidence of disease in the earliest years of life and presented at the ages of 3 1/2 and 4 1/2 years, respectively, with symptoms and signs of rapidly progressing intracranial hypertension. In both cases contrast-enhanced computerized tomography and magnetic resonance imaging revealed masses in the subdural space of the skull base and the cranial vault associated with significant subdural fluid collections. In the first case the lesion was misdiagnosed in the initial phase and treated, by means of multiple craniotomies, as an organized subdural hematoma. After a diagnosis of liposarcoma had been made, the patient was treated with chemotherapy, which resulted in a good resolution of the lesions at 3-month follow-up review. In the second case a biopsy allowed the diagnosis of fibrohistiocytic sarcoma and the patient was treated with chemotherapy. The authors review the literature of the few reported cases and discuss the possible pathophysiological association between pericerebral fluid collection and the subsequent development of a subdural sarcoma.
“Miliary” metastatic tumors in the brain
Authors: Bhushan Chhabi
Published: June 2009

✓ An extremely unusual “miliary” metastatic tumor of the brain in a 69-year-old man is reported. Although there was no known primary tumor, the patient had innumerable brain lesions involving both cerebral and both cerebellar hemispheres, the basal ganglia, and the brainstem. There was no associated edema, mass effect, or brain parenchymal reaction. None of the lesions showed any calcification.
Hypoplastic internal carotid artery mimicking a classic angiographic “string sign”
Authors: Heth Jason A. , Loftus Christopher M. , Piper John G. , Yuh William
Published: June 2009

✓ The authors report the case of a patient with transient ischemic attacks who was evaluated by duplex scanning, which demonstrated total carotid artery occlusion. Arteriography revealed what appeared to be a classic “string sign” in the cervical carotid artery, and a standard endarterectomy was planned. At surgery the internal carotid artery was found to be congenitally atretic, accounting for the string appearance of the arteriogram. The etiology, associated anomalies, differential diagnosis, and diagnostic evaluation of such lesions are discussed.
Neuromagnetic evaluation of cortical auditory function in patients with temporal lobe tumors
Authors: Nakasato Nobukazu , Kumabe Toshihiro , Kanno Akitake , Ohtomo Satoru , Mizoi Kazuo , Yoshimoto Takashi
Published: June 2009

✓ The N100m wave response of the auditory evoked magnetic field originates in the posterior part of the bilateral superior temporal planes for either contra- or ipsilateral ear stimulus. Cortical auditory function was evaluated in 14 patients with temporal lobe tumors using a magnetic resonance (MR) imaging—linked whole-head magnetoencephalography (MEG) system. Before surgery, seven patients had normal N100m latency (within the range of the mean ± 2 standard deviations of 37 normal volunteers) in both normal hemispheres and in those with lesions, and MR imaging indicated no tumor invasion or edema in the posterior one-third of the superior temporal planes, even when the sylvian fissure was shifted upward due to the mass effect. Seven patients had prolonged N100m latency or absence of N100m in the hemisphere containing the lesion, and the posterior portion of the superior temporal plane was involved by the tumor or perifocal edema. Prolonged N100m latency recovered to the normal range after removal of tumors in two of four patients investigated postoperatively. The MEG system can be used to evaluate cortical auditory function noninvasively before and after surgical treatment of temporal lobe tumors.
Comparison of C1–2 posterior fusion and decompression of the vertebral artery in the treatment of bow hunter's stroke
Authors: Matsuyama Takeshi , Morimoto Tetsuya , Sakaki Toshisuke
Published: June 2009

✓ Bow hunter's stroke results from vertebrobasilar insufficiency caused by mechanical occlusion or stenosis of the vertebral artery (VA) at the C1–2 level on head rotation. Surgical treatment of this condition may be chosen to avoid life-threatening accidents or because patients complain that conservative treatments such as verbal warnings or use of a neck brace to limit head and neck rotation are ineffective and thus restrict their lifestyle. Posterior fusion involving C1–2 has long been used to limit atlantoaxial rotational movements. However, it has the serious disadvantage that the range of head motion is severely reduced. Recently, decompression of the atlantoaxial portions of the affected VA has been used because it does not limit physiological neck movements. However, no long-term follow-up review of patients who have undergone this procedure has been conducted, and it is unclear whether this procedure always provides relief of symptoms. To answer this question, the results of C1–2 posterior fusion were compared with decompression of the VA for the treatment of bow hunter's stroke.
Acute hydrocephalus in posterior fossa injury
Authors: Karasawa Hideharu , Furuya Hajime , Naito Hiromichi , Sugiyama Ken , Ueno Junji , Kin Hiroshi
Published: June 2009

✓ This is the first known report of the use of computerized tomography (CT) scanning to examine acute hydrocephalus in posterior fossa injury. Of the 1802 patients with acute head trauma treated at Funabashi Municipal Medical Center, 53 (2.9%) had suffered injury to the posterior fossa. Of these, 12 patients (22.6%) had associated acute hydrocephalus: nine patients with acute epidural hematoma (AEH) and three with intracerebellar hematoma and contusion (IH/C). There was a significant relationship between cases of AEH with hydrocephalus and supratentorial extension, hematoma thickness of 15 mm or more, and abnormal mesencephalic cisterns. In cases of IH/C, bilateral lesions and no visible fourth ventricle were significant causes of hydrocephalus. According to these results, possible mechanisms of acute hydrocephalus in posterior fossa injury may be as follows: in cases of AEH, hematoma that extends to the supratentorial area compresses the aqueduct posteriorly and causes hydrocephalus; in cases of IH/C, hematoma and contusional lesions may directly occlude the fourth ventricle and cause acute hydrocephalus.

Seven patients suffering from AEH with acute hydrocephalus underwent evacuation of their hematoma without external ventricular drainage. In these cases, CT scanning showed that the hydrocephalus improved immediately after evacuation of the hematoma. Two patients suffering from IH/C with hydrocephalus underwent a procedure for evacuation of the hematoma and external ventricular drainage. The authors do not believe that ventricular drainage is necessary in treating posterior fossa AEH. However, both evacuation of the hematoma and ventricular drainage are necessary in cases of IH/C with hydrocephalus to provide the patient with every chance for survival.

There was no significant difference in mortality rates when cases of AEH with acute hydrocephalus (0%) were compared with cases of AEH without hydrocephalus (7.7%). The observed mortality rates in cases of IH/C with hydrocephalus and those without hydrocephalus were 100% and 15.4%, respectively; this is statistically significant.
Cerebral blood flow as a predictor of outcome following traumatic brain injury
Authors: Kelly Daniel F. , Martin Neil A. , Kordestani Rouzbeh , Counelis George , Hovda David A. , Bergsneider Marvin , McBride Duncan Q. , Shalmon Ehud , Herman Dena , Becker Donald P.
Published: June 2009

✓ As part of a prospective study of the cerebrovascular effects of head injury, 54 moderate and severely injured patients underwent 184 133Xe—cerebral blood flow (CBF) studies to determine the relationship between the period of maximum blood flow and outcome. The lowest blood flows were observed on the day of injury (Day 0) and the highest CBFs were documented on postinjury Days 1 to 5. Patients were divided into three groups based on CBF values obtained during this period of maximum flow: Group 1 (seven patients), CBF less than 33 ml/100 g/minute on all determinations; Group 2 (13 patients), CBF both less than and greater than or equal to 33 ml/100 g/minute; and Group 3 (34 patients), CBF greater than or equal to 33 ml/100 g/minute on all measurements. For Groups 1, 2, and 3, mean CBF during Days 1 to 5 postinjury was 25.7 ± 4, 36.5 ± 4.2, and 49.4 ± 9.3 ml/100 g/minute, respectively, and PaCO2 at the time of the CBF study was 31.4 ± 6, 32.7 ± 2.9, and 33.4 ± 4.7 mm Hg, respectively.

There were significant differences across Groups 1, 2, and 3 regarding mean age, percentage of individuals younger than 35 years of age (42.9%, 23.1%, and 76.5%, respectively), incidence of patients requiring evacuation of intradural hematomas (57.1%, 38.5%, and 17.6%, respectively) and incidence of abnormal pupils (57.1%, 61.5%, and 32.4%, respectively). Favorable neurological outcome at 6 months postinjury in Groups 1, 2, and 3 was 0%, 46.2%, and 58.8%, respectively (p < 0.05). Further analysis of patients in Group 3 revealed that of 14 with poor outcomes, six had one or more episodes of hyperemia-associated intracranial hypertension (simultaneous CBF > 55 ml/100 g/minute and ICP > 20 mm Hg). These six patients were unique in having the highest CBFs for postinjury Days 1 to 5 (mean 59.8 ml/100 g/minute) and the most severe degree of intracranial hypertension and reduced cerebral perfusion pressure (p < 0.0001).

These results indicate that a phasic elevation in CBF acutely after head injury is a necessary condition for achieving functional recovery. It is postulated that for the majority of patients, this rise in blood flow results from an increase in metabolic demands in the setting of intact vasoreactivity. In a minority of individuals, however, the constellation of supranormal CBF, severe intracranial hypertension, and poor outcome indicates a state of grossly impaired vasoreactivity with uncoupling between blood flow and metabolism.
Peripheral selective neurotomy of the brachial plexus collateral branches for treatment of the spastic shoulder: anatomical study and clinical results in five patients
Authors: Decq Philippe , Filipetti Paul , Feve Annaïk , Djindjian Michel , Saraoui Akim , Kéravel Yves
Published: June 2009

✓ A new type of peripheral selective neurotomy involving the collateral branches of the brachial plexus has been perfected for treatment of the spastic shoulder. Anatomical study of six cadaveric shoulders led to the specification of a surgical approach to the pectoralis major and teres major nerves, which innervate the main muscles implicated in shoulder spasticity. Between August 1994 and September 1995, five patients (four men and one woman) underwent two to four associated neurotomies of the upper limb, which included neurotomies of the pectoralis major (all five patients) and the teres major (two patients). The average follow-up period was 11 months, during which there were no local or general complications. The spasticity of the treated muscles resolved in all five patients (Held score range 3—0). The neurotomies led to statistically significant average amplitude increases in shoulder mobility, especially in abduction (+30°), antepulsion (+50°), retropulsion (+20°), and external rotation (+20°). The functionally useful active amplitude scores increased from 2.66 to 5.16/6. This functional improvement mainly involved the standing position and walking stability, as well as improvement in the range of motion of the lower limb. These results encourage the increasing use of this new type of neurotomy in treatment of the spastic upper limb.
Improvement of limb circulation in peripheral vascular disease using epidural spinal cord stimulation: a prospective study
Authors: Kumar Krishna , Toth Cory , Nath Rahul K. , Verma Ashok K. , Burgess John J.
Published: June 2009

✓ Spinal cord stimulation was used in 46 patients for pain associated with lower extremity ischemic vascular disease that was considered to be nonreconstructable. Thirty-nine patients who had a follow-up examination between 2 and 36 months after the procedure form the basis of this report. Thirty (77%) of 39 cases were considered successful. Clinical endpoints indicating failure included amputation, vascular reconstruction, poor pain relief, or hardware malfunction. The transcutaneous partial pressure of oxygen (TcPO2) increased in both target and control feet. In patients with good outcome with a preimplantation TcPO2 of less than 30 mm Hg, TcPO2 increased significantly (p < 0.05). Pulse volume recording improved significantly (p < 0.05) at the thigh, metatarsal, and great toe levels in successfully treated patients. Peak blood flow velocity also showed a significant increase in patients with good outcome (p < 0.05). Patients with a TcPO2 of less than 10 mm Hg following stimulation tended to undergo amputation within the first 3 months.

Improvement in pain control, combined with an increase in TcPO2 values that was greater than 10 mm Hg, were significant early predictors of long-term success. An initial increase in peak blood flow velocities (measured in Doppler studies) of greater than 10 mm also signified a good long-term outcome. Spinal cord stimulation appears to be a useful therapeutic modality for controlling pain and improving perfusion in a select group of patients with end-stage ischemic vascular disease considered nonreconstructable. The best results were seen in patients with severe claudication and rest pain without trophic changes in the foot. The mechanism of this beneficial effect is not yet completely understood.
Secondary multiple intracranial hydatid cysts caused by intracerebral embolism of cardiac echinococcosis: an exceptional case of hydatidosis
Authors: Turgut Mehmet , Benli Kemal , Eryilmaz Muzaffer
Published: June 2009

✓ The authors present an extremely rare case of secondary multiple cerebral echinococcosis caused by presumed intracerebral and arterial embolism of cardiac hydatidosis in a 7-year-old girl. The first manifestations were symptoms of raised intracranial pressure. Unfortunately, before the primary ruptured echinococcosis cyst was detected in the myocardium of the left ventricle, the patient underwent nine operations over an 8-year period for hydatid embolism affecting the brain and the femoral artery and was treated with concurrent mebendazole therapy. The combined therapy would not have been successful without removal of the intracardiac hydatid cyst. This case is unusual because of the multiplicity of intracranial hydatid cysts and its embolic origin from cardiac echinococcosis. The present case is believed to be the first one in which the development of an embolism in the brain was studied by magnetic resonance imaging.
Balloon-assisted coil placement in wide-necked aneurysms
Authors: Levy David I. , Ku Andrew
Published: June 2009

✓ Saccular intracranial aneurysms are a common and often fatal lesion. Whereas surgical treatment of these aneurysms continues to be the gold standard of care, certain situations arise for which surgery may not be the best option. In some of these cases, electrolytically detachable coils have been proven to provide outcomes superior to those seen for medical management alone. The authors present two cases of ophthalmic artery aneurysms that would not hold the Guglielmi detachable coils on the initial attempt. One aneurysm was 7 mm and one 4 mm, both with wide necks relative to the aneurysm sac. By using a balloon-assisted technique and blocking the parent artery with a nondetachable balloon, the coils could be safely placed in these aneurysms without herniation when the balloon was deflated. Both patients exhibited embolic symptoms after the procedure, one with a mild but permanent deficit. Although this technique requires manipulation of a second microcatheter and balloon, which increases its technical difficulties and is a higher risk procedure than standard coil placement, it has utility in patients who are not candidates for surgery.
Carboplatin and vincristine chemotherapy for children with newly diagnosed progressive low-grade gliomas
Authors: Packer Roger J. , Ater Joanne , Allen Jeffrey , Phillips Peter , Geyer Russell , Nicholson H. Stacy , Jakacki Regina , Kurczynski Elizabeth , Needle Michael , Finlay Jonathan , Reaman Gregory , Boyett James M.
Published: June 2009

✓ The optimum treatment of nonresectable low-grade gliomas of childhood remains undecided. There has been increased interest in the use of chemotherapy for young children, but little information concerning the long-term efficacy of such treatment. Seventy-eight children with a mean age of 3 years (range 3 months—16 years) who had newly diagnosed, progressive low-grade gliomas were treated with combined carboplatin and vincristine chemotherapy. The patients were followed for a median of 30 months from diagnosis, with 31 patients followed for more than 3 years. Fifty-eight children had diencephalic tumors, 12 had brainstem gliomas, and three had diffuse leptomeningeal gliomas. Forty-four (56%) of 78 patients showed an objective response to treatment. Progression-free survival rates were 75 ± 6% at 2 years and 68 ± 7% at 3 years. There was no statistical difference in progression-free survival rates between children with neurofibromatosis Type 1 and those without the disease (2-year, progression-free survival 79 ± 11% vs. 75 ± 6%, respectively). The histological subtype of the tumor, its location, and its maximum response to chemotherapy did not have an impact on the duration of disease control. The only significant prognostic factor was age: children 5 years old or younger at the time of treatment had a 3-year progression-free survival rate of 74 ± 7% compared with a rate of 39 ± 21% in older children (p < 0.01). Treatment with carboplatin and vincristine is effective, especially in younger children, in controlling newly diagnosed progressive low-grade gliomas.
Fibrinolytic parameters as an admission prognostic marker of head injury in patients who talk and deteriorate
Authors: Takahashi Hiroshi , Urano Tetsumei , Takada Yumiko , Nagai Nobuo , Takada Akikazu
Published: June 2009

✓ Because it has been difficult to predict the outcome of patients with head injury in the early period after admission, a clinical study was undertaken to evaluate if the fibrinolytic parameters could be reliable indicators of outcome. Seventy patients presenting with head injury without obvious trauma in other regions were studied, and plasma levels of α2-plasmin inhibitor—plasmin complex (PIC) and D-dimer on admission (within 2 hours postinjury) were assessed. Plasma levels of both PIC and D-dimer were elevated and correlated well to patient outcomes. When plasma PIC levels were higher than 15 µg/ml or D-dimer levels were higher than 5 µg/ml, 92% of patients died regardless of their consciousness level on admission, whereas all patients made good recoveries when their PIC levels were less than 2 µg/ml or D-dimer levels were less than 1 µg/ml. Therefore, plasma levels of both PIC and D-dimer on admission were revealed to be reliable prognostic markers of head injury. Using these markers, patients with poor outcomes (progressive brain injury), such as “talk and deteriorate” types, could be readily identified on admission.
Clonality of multiple meningiomas
Authors: Stangl Armin P. , Wellenreuther Ruth , Lenartz Doris , Kraus Jürgen A. , Menon Anil G. , Schramm Johannes , Wiestler Otmar D. , von Deimling Andreas
Published: June 2009

✓ A significant number of patients with meningiomas develop multiple tumors without anatomical bridges. To understand the mechanism by which multiple meningiomas arise, the authors analyzed DNA from 39 multiple meningiomas in 12 patients to locate alterations in the neurofibromatosis type 2 (NF2) gene. This gene has been shown to be inactivated in meningiomas. No patient in our series had a family history of meningiomas or NF2. All tumors were investigated by single-strand conformation polymorphism analysis of the entire coding region of the NF2 gene and by direct DNA sequencing of altered fragments. The DNA from meningiomas in 10 patients carried NF2 gene mutations. In six of the 10 patients with NF2 mutations, all tumors in the respective individual exhibited the identical DNA alteration in the NF2 gene, thus indicating clonal origin. All four patients with more than two lesions had clonal meningiomas and four patients with two meningiomas each carried different mutations in their tumors. Analysis of constitutional DNA revealed a wild-type NF2 sequence in all 12 patients, thus excluding a forme fruste of NF2 in these cases. Our data demonstrate that the majority of multiple meningiomas with NF2 gene mutations are of somatic and clonal origin. Spread of tumor cells via the cerebrospinal fluid is the most likely mechanism to account for the development of these multiple meningiomas.
Potential efficacy of basic fibroblast growth factor incorporated in biodegradable hydrogels for skull bone regeneration
Authors: Yamada Keisuke , Tabata Yasuhiko , Yamamoto Kazuo , Miyamoto Susumu , Nagata Izumi , Kikuchi Haruhiko , Ikada Yoshito
Published: June 2009

✓ Biodegradable gelatin hydrogels incorporating basic fibroblast growth factor (bFGF) were evaluated for their efficacy in bone regeneration using a rabbit model. Hydrogels with water contents of 85% and 98% were prepared using chemical crosslinking of gelatin with an isoelectric point of 4.9 in aqueous solution and, after freeze drying, were impregnated with an aqueous solution of bFGF to obtain bFGF-incorporated gelatin hydrogels. When they were implanted into bone defects measuring 6 mm in diameter in rabbit skulls (six animals/group), complete closure of the defect was observed at 12 weeks after implantation, regardless of the water content of the hydrogels. In contrast, bFGF did not enhance bone regeneration when applied to the skull defect in solution with phosphate-buffered saline (PBS). Also, gelatin hydrogels lacking bFGF were not effective in inducing bone formation, with fibrous tissue growing into the defect instead, similar to the skull defect seen in control rabbits treated with PBS. This indicates that the presence of hydrogels did not interfere with bone regeneration at the skull defect, probably because of their disappearance during biodegradation. It is concluded that the gelatin hydrogel is a promising matrix for effective induction of biological activity of bFGF for bone regeneration in skull and sinus defects.
Anaplastic ependymoma: treatment of pediatric patients with or without craniospinal radiation therapy
Authors: Merchant Thomas E. , Haida Toni , Wang Ming-Hsien , Finlay Jonathan L. , Leibel Steven A.
Published: June 2009

✓ The authors conducted a retrospective review of the clinical and treatment characteristics and outcomes in 28 pediatric patients with anaplastic ependymoma treated with radiation therapy since the advent of computerized tomography (CT) (1978–1994). Twelve patients received craniospinal irradiation followed by a boost to the primary site, two received whole-brain radiation therapy followed by a boost to the primary site, and the remaining 14 were treated with focal radiation therapy. The mean dose to the primary site was 5486 cGy. With a median follow-up period of 86 months for the 14 surviving patients (range 31–201 months), the median disease-free survival, measured from the date of diagnosis to the time of recurrence after radiation therapy, was 40 months. The median disease-free survival measured from the start of radiation therapy was 32 months. The median overall survival rate has not been reached and the actuarial estimates of overall survival rates at 5 and 10 years were 56% and 38%, respectively. According to univariate analysis, the disease-free survival rate was significantly improved (p < 0.01) in patients who underwent a gross-total resection at diagnosis. Overall survival rates were negatively influenced by treatment with craniospinal and whole-brain irradiation. As calculated by multivariate analysis, increasing dosage to the primary site (p < 0.05), infratentorial location (p < 0.01), and gross-total resections (p < 0.02) resulted in the longest disease-free survival times. All 19 patients in whom treatment failed after radiation therapy suffered a recurrence at the primary site. In addition, one of these patients experienced subarachnoid dissemination. Radiation treatment recommendations for patients with ependymoma have been based on the tumor's location, perceived risk for dissemination, and malignant propensity. The significance of anaplastic histological classification is controversial. Differences in the disease-free and overall survival rates have been demonstrated between ependymomas and anaplastic ependymomas treated in the pre—CT era. The results of this study show that there is no benefit from craniospinal irradiation in this group of patients.
Radiological and anatomical evaluation of the atlantoaxial transarticular screw fixation technique
Authors: Madawi Ali Abou , Casey Adrian T. H. , Solanki Guirish A. , Tuite Gerald , Veres Robert , Crockard H. Alan
Published: June 2009

✓ Sixty-one patients treated with C1–2 transarticular screw fixation for spinal instability participated in a detailed clinical and radiological study to determine outcome and clarify potential hazards. The most common condition was rheumatoid arthritis (37 patients) followed by traumatic instability (15 patients). Twenty-one of these patients (onethird) underwent either surgical revision for a previously failed posterior fusion technique or a combined anteroposterior procedure. Eleven patients underwent transoral odontoidectomy and excision of the arch of C-1 prior to posterior surgery. No patient died, but there were five vertebral artery (VA) injuries and one temporary cranial nerve palsy. Screw malposition (14% of placements) was comparable to another large series reported by Grob, et al. There were five broken screws, and all were associated with incorrect placement.

Anatomical measurements were made on 25 axis bones. In 20% the VA groove on one side was large enough to reduce the width of the C-2 pedicle, thus preventing the safe passage of a 3.5-mm diameter screw.

In addition to the obvious dangers in patients with damaged or deficient atlantoaxial lateral mass, the following risk factors were identified in this series: 1) incomplete reduction prior to screw placement, accounting for two-thirds of screw complications and all five VA injuries; 2) previous transoral surgery with removal of the anterior tubercle or the arch of the atlas, thus obliterating an important fluoroscopic landmark; and 3) failure to appreciate the size of the VA in the axis pedicle and lateral mass. A low trajectory with screw placement below the atlas tubercle was found in patients with VA laceration.

The technique that was associated with an 87% fusion rate requires detailed computerized tomography scanning prior to surgery, very careful attention to local anatomy, and nearly complete atlantoaxial reduction during surgery.
Primary reconstruction for spinal infections
Authors: Dietze Donald D. , Fessler Richard G. , Jacob R. Patrick
Published: June 2009

✓ Primary reconstruction using bone grafts and instrumentation for spinal infections remains controversial. Between 1991 and 1993, 27 infections of the spinal column were treated at the Department of Neurosurgery of the University of Florida. Of the 27 cases 20 (six cervical, eight thoracic, and six lumbar spine) required surgical debridement and spinal reconstruction to maximize eradication of the infection and maintenance of spinal alignment. All of the cervical and lumbar cases were caused by bacterial infections, and two of eight thoracic cases were caused by tuberculous infections. Spinal arthrodesis was performed in all cases: interbody grafts were used in 18 procedures and posterolateral onlay grafts in 14. Interbody grafts were autologous in 10 cases (six rib and four iliac crest) and allograft in eight (six fibular and two humerus). All of the posterolateral onlay grafts were autologous (three rib and 11 iliac crest). Spinal instrumentation was used in 15 cases: four with Caspar plates and 11 with posterior segmental fixation (five hook/rod constructs and six screw/rod constructs). Seventeen of 20 patients achieved improved clinical status postoperatively and 18 of 20 showed radiographic evidence of bone fusion. Antibiotic drugs were administered parenterally for an average of 6 weeks followed by a 3-month course of oral antibiotic medications. Tuberculous infections were treated for 1 year with antibiotic therapy. The after completion of treatment with antibiotic drugs. The authors conclude that primary arthrodesis and instrumentation can be performed in acute spinal infections; however, successful management depends on aggressive debridement of infectious foci and prolonged treatment with parenteral antibiotic drugs.
Development of a dural substitute from synthetic bioabsorbable polymers
Authors: Yamada Keisuke , Miyamoto Susumu , Nagata Izumi , Kikuchi Haruhiko , Ikada Yoshito , Iwata Hiroo , Yamamoto Kazuo
Published: June 2009

✓ A new bioabsorbable composite sheet was developed to provide a substitute for the dura mater and was evaluated histologically and biomechanically using rats and rabbits. This composite, composed of two l-lactic acid-ϵ-caprolactone (50% l-lactic acid, 50% ϵ-caprolactone) copolymer films and a poly(glycolic acid) nonwoven fabric, displayed good mechanical properties and was completely absorbed 24 weeks after implantation in the back of rats. Histological evaluation of the composite sheet was undertaken by implanting it in 31 rabbits with dural defects and examining the sites of implantation 2 weeks to 26 months later. No infection, cerebrospinal fluid leakage, evidence of convulsive disorders, significant adhesion to underlying cortex, or calcification was noticed in any cases. In addition, the regenerated duralike tissue had a high pressure-resistant strength 2 weeks after implantation. The authors conclude that this new bioabsorbable composite sheet can be successfully used as a dural substitute.
Saphenous vein graft bypass of the sigmoid sinus and jugular bulb during the removal of glomus jugulare tumors
Authors: Sekhar Laligam N. , Tzortzidis Fotios N. , Bejjani Ghassan K. , Schessel David A.
Published: June 2009

✓ Glomus jugulare tumors always invade the jugular bulb and sigmoid sinus, making it difficult to resect these tumors totally without sacrificing the involved sinus. Although the sinus can be sacrificed safely in most patients, a few patients will have serious consequences. Reconstruction of the jugular bulb using a saphenous vein graft may enable tumor resection in these patients without complications.

The authors describe two cases of saphenous vein grafting used to bypass the sigmoid sinus.

The first case is that of a 61-year-old man with a glomus jugulare tumor that invaded the dominant sigmoid sinus, which was poorly collateralized. Temporary occlusion of the sinus during surgery caused a 15-mm Hg increase in intrasinus pressure, without brain swelling or changes in evoked potentials. A saphenous vein graft was used to bypass the sigmoid sinus and jugular bulb and to allow for total tumor removal. The patient had a good outcome.

The second case is that of a 41-year-old man with a left glomus jugulare tumor and another smaller tumor on the opposite, dominant sinus. The left glomus jugulare tumor was resected via a two-stage procedure. A saphenous vein graft was used to reconstruct the left sigmoid sinus because of the presence of contralateral disease, with the potential for bilateral sigmoid sinus occlusion.

An evaluation of the venous collateral circulation during jugular foramen surgery and the prevention of complications are also discussed.
Solitary fibrous tumor of the meninges
Authors: Prayson Richard A. , McMahon James T. , Barnett Gene H.
Published: June 2009

✓ The authors present the case of a left frontal solitary fibrous tumor of the meninges. The gross appearance of the tumor was very similar to that of a fibroblastic meningioma. Histological examination showed a mixture of spindle-shaped and round cells arranged in a collagen matrix. Immunohistochemical staining of the tumor demonstrated diffuse positive staining for CD34 and vimentin. The tumor displayed no positive staining for markers of muscle, epithelial, glial, or neurocrest differentiation or for estrogen and progesterone receptors. The MIB-1 labeling index (the percentage of positive staining tumor cell nuclei), a marker of cellular proliferation, was 1.1%. Ultrastructural studies support attributing a mesenchymal, rather than meningothelial, nature to the tumor. A differential diagnosis is discussed and a review of the literature on these rare tumors is presented.
Facial nerve injury in acoustic neuroma (vestibular schwannoma) surgery: etiology and prevention
Authors: Sampath Prakash , Holliday Michael J. , Brem Henry , Niparko John K. , Long Donlin M.
Published: June 2009

✓ Facial nerve injury associated with acoustic neuroma surgery has declined in incidence but remains a clinical concern. A retrospective analysis of 611 patients surgically treated for acoustic neuroma between 1973 and 1994 was undertaken to understand patterns of facial nerve injury more clearly and to identify factors that influence facial nerve outcome.

Anatomical preservation of the facial nerve was achieved in 596 patients (97.5%). In the immediate postoperative period, 62.1% of patients displayed normal or near-normal facial nerve function (House—Brackmann Grade 1 or 2). This number rose to 85.3% of patients at 6 months after surgery and by 1 year, 89.7% of patients who had undergone acoustic neuroma surgery demonstrated normal or near-normal facial nerve function.

The surgical approach appeared to have no effect on the incidence of facial nerve injury. Poor facial nerve outcome (House—Brackmann Grade 5 or 6) was seen in 1.58% of patients treated via the suboccipital approach and in 2.6% of patients treated via the translabyrinthine approach. When facial nerve outcome was examined with respect to tumor size, there clearly was an increased incidence of facial nerve palsy seen in the immediate postoperative period in cases of larger tumors: 60.8% of patients with tumors smaller than 2.5 cm had normal facial nerve function, whereas only 37.5% of patients with tumors larger than 4 cm had normal function. This difference was less pronounced, however, 6 months after surgery, when 92.1% of patients with tumors smaller than 2.5 cm had normal or near normal facial function, versus 75% of patients with tumors larger than 4 cm.

The etiology of facial nerve injury is discussed with emphasis on the pathophysiology of facial nerve palsy. In addition, on the basis of the authors' experience with these complex tumors, techniques of preventing facial nerve injury are discussed.
A comparison of proliferation indices in human anterior pituitary adenomas using formalin-fixed tissue and in vitro cell culture
Authors: Atkin Stephen L. , Green Victoria L. , Hipkin Leslie J. , Landolt Alex M. , Foy Patrick M. , Jeffreys Richard V. , White Michael C.
Published: June 2009

✓ The authors compared detection methods for cell proliferation in human anterior pituitary adenomas using histological sections and dispersed cell culture. After tumor cells had been grown for 4 days in dispersed culture, bromodeoxyuridine (BUdR), proliferating cell nuclear antigen (PCNA), and Ki-67 were compared by double immunostaining and contrasted with single staining of PCNA and Ki-67 indices in the corresponding histological sections from 12 human pituitary adenomas. In vitro, the BUdR labeling index was positive in six of 12 tumors (range < 0.1–5.1%), 10 of 12 tumors were PCNA-positive (range < 0.1–100%), and Ki-67 was positive in 10 of 12 adenomas (range < 0.1–8%). In vitro, BUdR and Ki-67 gave similar proliferative indices for 10 of 12 adenomas. In vivo, the PCNA labeling index was positive in 12 of 12 adenomas (range 0.9–95%) and Ki-67 was positive in 11 of 12 adenomas (range < 0.1–2%). Tumors with a labeling index less than 0.1% were considered to be negative for proliferation. High PCNA values were found in vitro and in vivo, whereas Ki-67 labeling indices were similar in vitro and in vivo for nine of 12 adenomas. It is concluded that Ki-67 proliferative indices in vivo reflect those found in vitro, at least after 4 days in dispersed culture, but that PCNA overestimates pituitary adenoma proliferation in histological sections as well as in dispersed culture.
Stenotrophomonas maltophilia meningitis
Authors: Papadakis Konstantinos A. , Vartivarian Shahe E. , Vassilaki Maria E. , Anaissie Elias J.
Published: June 2009

✓ The authors report two cases of meningitis caused by Stenotrophomonas maltophilia in cancer patients following placement of an Ommaya reservoir for treatment of meningeal carcinomatosis. In addition, they review eight other cases of S. maltophilia that have been reported to date. Stenotrophomonas maltophilia meningitis is often associated with neurosurgical procedures; however, spontaneous infection may also occur, mainly in neonates. The disease's clinical presentation is similar to that of other forms of meningitis caused by Gram-negative bacilli. The overall mortality rate of this disease is 20% and is limited to neonates with spontaneous meningitis in whom effective antibiotic therapy is delayed. Meningitis caused by S. maltophilia in the modern era should be considered in immunocompromised hosts with significant central nervous system disease who have undergone neurosurgical procedures and who do not readily respond to broad-spectrum antimicrobial coverage.
Contralateral approaches to bilateral cerebral aneurysms: a microsurgical anatomical study
Authors: Oshiro Eric M. , Rini David A. , Tamargo Rafael J.
Published: June 2009

✓ In patients with bilateral supratentorial aneurysms, surgical clipping of all aneurysms via a unilateral approach would obviate the need for a second operation. The authors conducted a microsurgical study in human cadaver heads to examine the contralateral exposure for four common aneurysm sites in the anterior circulation: the ophthalmic artery (OA) origin, the posterior communicating artery (PCoA) origin, the internal carotid artery (ICA) termination, and the middle cerebral artery (MCA) bifurcation. Frontotemporal craniotomies were performed in 16 cadavers to evaluate the corridor for exposure of these sites from the contralateral side. Morphometric data, including lengths and diameters of major arterial segments and optic nerves, were documented for anatomical correlation.

In this study, the contralateral OA origin was successfully exposed in 62% of specimens, the PCoA origin in 50%, the ICA bifurcation in 100%, and the MCA bifurcation in 62%. Exposure of the OA origin and, in some cases, the PCoA, required incision of the falciform ligament and mobilization of the contralateral optic nerve. Exposure of the MCA bifurcation was dependent on the length of the M1 segment, with successful exposure only when this segment was shorter than 14 mm. Implications for the contralateral approach to aneurysms at these sites are discussed and the microsurgical corridors for exposure are described.

For correlation with the anatomical study, a brief clinical review of patients with bilateral supratentorial aneurysms treated at The Johns Hopkins Hospital between 1992 and 1995 is presented. Guidelines for the contralateral approach to aneurysms are discussed with reference to the anatomical study and the clinical review.
Cerebral cavernous malformations: natural history and prognosis after clinical deterioration with or without hemorrhage
Authors: Porter Phillip J. , Willinsky Robert A. , Harper William , Wallace M. Christopher
Published: June 2009

✓ Despite recent studies of the natural history of cavernous malformations, there remains significant uncertainty concerning hemorrhage rates and the importance of lesion location. Controversy arises over varying definitions of “hemorrhage.” What is ultimately important to the patient is the occurrence of a neurological event, which may or may not be associated with radiologically documented hemorrhage, as well as the chance of recovery after such an event. The purpose of this study was to determine the rates of occurrence and sequelae of neurological events in 173 patients referred to our vascular malformation clinic with cavernous malformations.

All patient data were entered into a database. The mean age at presentation for the 173 patients was 37.5 years. The lesion location was deep (brainstem, cerebellar nuclei, thalamus, or basal ganglia) in 64 patients (37%) and superficial in 109 (63%). Thirty-one patients (18%) had multiple lesions. Disease presentation was due to seizures in 62 patients (36%), hemorrhage in 44 (25%), focal neurological deficit without documented hemorrhage in 35 (20%), headache alone in 11 (6%), and incidental findings in 21 patients (12%). The results obtained in the 110 patients eligible for follow-up review were used to derive information on the rates of hemorrhage and neurological events. An interval event (neurological deterioration) required both symptoms and signs. The total mean follow-up period was 46 months, the majority (65%) of which was prospective. There were 18 interval events in 427 patient-years of follow-up review, for an overall annual event rate of 4.2%. Location was the most important factor for predicting interval event occurrence, with significantly higher rates for deeply located (10.6%/year) compared with superficially located lesions (0%/year) (p = 0.0001). Of patients suffering a neurological event, only 37% had complete resolution of their deficits.

This largely prospective study indicates that deep cavernous malformations carry a worse prognosis than superficial lesions with respect to annual rates of neurological deterioration. The alarming rate of adverse clinical events occurring in patients with deep lesions is punctuated by the fact that less than one-half of them recover fully during long-term follow-up review.
Hemodynamically significant cerebral vasospasm and outcome after head injury: a prospective study
Authors: Lee Jae Hong , Martin Neil A. , Alsina George , McArthur David L. , Zaucha Ken , Hovda David A. , Becker Donald P.
Published: June 2009

✓ The authors prospectively investigated cerebral hemodynamic changes in 152 patients with head injuries to clarify the relationship between cerebral vasospasm and outcome. They also sought to determine the most clinically meaningful criteria for diagnosing cerebral vasospasm. Patients with varying degrees of moderate-to-severe head injury were monitored using transcranial Doppler (TCD) ultrasonography and intravenous 133Xe—cerebral blood flow (CBF) measurements. Outcome was determined at 6 months. Using TCD ultrasonography, mean flow velocities were determined for the middle cerebral artery (VMCA, 149 patients) and basilar artery (VBA, 126 patients). Recordings of the mean extracranial internal carotid artery velocity (VEC-ICA) were also performed to determine the hemispheric ratio (VMCA/VEC-ICA, 147 patients). Cerebral blood flow measurements were obtained in 91 patients. Concurrent TCD and CBF data from 85 patients were used to calculate a “spasm index” (the VMCA or VBA, respectively, divided by the hemispheric or global CBF). The authors investigated the clinical significance of elevated flow velocity, hemispheric ratio, and spasm index. Patients diagnosed as having MCA or BA vasospasm on the basis of TCD-derived criteria alone had a significantly worse outcome than patients without vasospasm. When CBF was considered, hemodynamically significant vasospasm, as defined by an elevated spasm index, was even more strongly associated with poor outcome. Stepwise logistic regression analysis confirmed that hemodynamically significant vasospasm was a significant predictor of poor outcome, independent of the effects of admission Glasgow Coma Scale score and age. On the basis of the results of this study, the authors suggest that the important factor impacting on outcome is not vasospasm per se, but hemodynamically significant vasospasm with low CBF. These findings show that vasospasm is a pathophysiologically important posttraumatic secondary insult, which is best diagnosed by the combined use of TCD and CBF measurements.