bluuebunny/crossref_metadata_2025 huggingface dataset:
Delayed Surgical Resection of Central Nervous System Germ Cell Tumors
Authors: Weiner Howard L. , Lichtenbaum Roger A. , Wisoff Jeffrey H. , Snow Robert B. , Souweidane Mark M. , Bruce Jeffrey N. , Finlay Jonathan L.
Published: July 2004

OBJECTIVE:

To determine the value of delayed surgical resection in patients with central nervous system germ cell tumors who exhibit less than complete radiographic response despite declining serum and cerebrospinal fluid (CSF) tumor markers after initial chemotherapy.

METHODS:

We retrospectively analyzed 126 patients enrolled on two international multicenter clinical trials (the First and Second International Central Nervous System Germ Cell Tumor Studies) for patients with newly diagnosed central nervous system germ cell tumors. After at least three cycles of chemotherapy, 10 of these patients underwent delayed surgical resection owing to evidence of residual radiographic abnormalities despite declining or completely normalized serum and CSF levels of α-fetoprotein and human chorionic gonadotropin.

RESULTS:

Eight of these patients demonstrated nongerminomatous germ cell tumor elements at the time of initial diagnosis. In these patients, either serum or CSF tumor markers were elevated initially. Two patients demonstrated pure germinomas with normal levels of serum and CSF tumor markers. After chemotherapy, radiographic evaluation revealed a partial response in seven patients, a minor response in one patient, and stable disease in two patients. All 10 patients had either normal or decreasing levels of serum and CSF tumor markers before second-look surgery. At delayed surgical resection, 7 of the 10 patients underwent gross total resection, and 3 patients underwent subtotal resection of residual lesions. Pathological findings at second-look surgery demonstrated three patients to have mature teratomas, two with immature teratomas, and five with necrotic or scar tissue alone. To date, 7 of the 10 patients have had no recurrence during an average follow-up time of 36.9 months (range, 3–96 mo). Three of four patients with nongerminomatous germ cell tumors who had tumor markers that were decreased, but not normalized, before second-look surgery eventually developed tumor dissemination/progression, and they required subsequent radiation therapy despite having teratoma or necrosis/scar tissue at delayed surgery. In contrast, three of four patients with nongerminomatous germ cell tumors and completely normalized markers did not progress and did not require radiation therapy.

CONCLUSION:

Delayed surgical resection should be considered in patients with central nervous system germ cell tumors who have residual radiographic abnormalities and normalized tumor markers, because these lesions are likely to be teratoma or necrosis/scar tissue. However, second-look surgery should be avoided in patients whose tumor markers have not normalized completely.
Characteristics of Ventricular Shunt Malfunctions among Patients with Neurocysticercosis
Authors: Kelley Rosemarie , Duong Duc H. , Locke George E.
Published: July 2004

OBJECTIVE:

Ventricular shunts used to relieve hydrocephalus among patients with neurocysticercosis have been plagued by high shunt malfunction rates. We examined the characteristics of shunt malfunctions among patients with neurocysticercosis.

METHODS:

This is a retrospective chart review of data for 122 patients who were admitted with a diagnosis of cysticercosis during a 5.5-year period. Cases of hydrocephalus requiring shunt placement were reviewed with respect to the segment of shunt obstruction, disease activity at the time of shunt placement, and the effects of antihelminthic treatment on shunt failures and longevity.

RESULTS:

Twenty-one patients required 49 operations for relief of hydrocephalus, including 22 new shunt placements, 23 revisions, and 4 cyst extirpations. Of these shunt failures, 78% occurred within the first 12 months and 96% within 3 years. Of the failures that occurred in the distal segment, 75% occurred within 6 months. By comparison, 33% of proximal segment obstructions and 50% of the total number of valve obstructions occurred within the first 6 months. Of the shunts placed during the vesicular stage of infection, 63% required revisions, compared with 29% of those placed during the colloidal through calcified stages. Nineteen shunts were placed during the vesicular stage, and nine patients received a full course of antihelminthic treatment after shunt placement. In less than 6 months, 33% of the cases involving shunt placement followed by antihelminthic treatment exhibited shunt failure, compared with 90% of the cases without antihelminthic treatment (P < 0.05, χ2 test).

CONCLUSION:

Among patients with vesicular stage cysticercosis, placement of a ventriculoperitoneal shunt followed by a course of antihelminthic medication seems to promote shunt longevity.
Quantitative Assessment of Surgical Decompression of the Cervical Spine with Cine Phase Contrast Magnetic Resonance Imaging
Authors: Tominaga Teiji , Watabe Noriaki , Takahashi Toshiyuki , Shimizu Hiroaki , Yoshimoto Takashi
Published: July 2004

OBJECTIVE:

We measured cerebrospinal fluid flow velocity by use of cine phase contrast magnetic resonance imaging to quantitate the effectiveness of surgical decompression in patients with cervical myelopathy.

METHODS:

Forty-seven patients with cervical myelopathy attributable to either spondylosis or ossification of the posterior longitudinal ligament were studied. Thirty-five patients underwent anterior cervical decompression and fusion; 12 others underwent expansive laminoplasty. Patients were examined preoperatively and postoperatively by use of a 1.5-T scanner with a pulse-gated cine phase contrast sequence. Cerebrospinal fluid flow direction and velocity in the ventral subarachnoid space were determined at the C1 and T1 levels. Forty-four healthy control subjects were examined to determine normal flow velocity parameters. Severity of cervical myelopathy was evaluated preoperatively and postoperatively by use of Japan Orthopedic Association scores to calculate the extent of recovery.

RESULTS:

Preoperatively, cerebrospinal fluid flow velocity in the caudal direction was significantly lower at both C1 and T1 than velocities measured in healthy controls. Both decompressive procedures essentially returned patient velocities to control values. Clinical recovery from myelopathy did not differ between anterior and posterior decompression. Postoperative increase in flow velocity correlated with clinical recovery after posterior (P < 0.0008) but not anterior decompression.

CONCLUSION:

Cine phase contrast magnetic resonance imaging provides quantitative assessment of cervical spine decompression, with particularly good clinical applicability to posterior procedures.
Neuronavigation by Intraoperative Three-dimensional Ultrasound: Initial Experience during Brain Tumor Resection
Authors: Unsgaard Geirmund , Ommedal Steinar , Muller Tomm , Gronningsaeter Aage , Nagelhus Hernes Toril A.
Published: July 2004

OBJECTIVE:

Three-dimensional (3-D) ultrasound is an intraoperative imaging modality used in neuronavigation as an alternative to magnetic resonance imaging (MRI). This article summarizes 4 years of clinical experience in the use of intraoperative 3-D ultrasound integrated into neuronavigation for guidance in brain tumor resection.

METHODS:

Patients were selected for inclusion in the study on the basis of the size and location of their lesion. Preoperative 3-D MRI data were registered and used for planning as in other conventional neuronavigation systems. Intraoperative 3-D ultrasound images were acquired three to six times, and tumor resection was guided on the basis of these updated 3-D images.

RESULTS:

Intraoperative 3-D ultrasound represents a good solution to the problem of brain shift in neuronavigation because it easily provides an updated, and hence more accurate, map of the patient's true anatomy in all phases of the operation. Ultrasound makes it possible to follow the progression of the operation, and it improves the radicality of tumor resection by detecting tumor tissue that would remain if the imaging technology had not been used (in 53% of the cases). Integration of 3-D ultrasound with navigation technology solves the orientation problem experienced previously with two-dimensional ultrasound in neurosurgery. The technology makes it possible to directly compare intraoperative ultrasound and MRI data regarding visualization of the lesion. Ultrasound image quality is useful for guiding surgical procedures.

CONCLUSION:

Intraoperative 3-D ultrasound seems to provide a time- and cost-effective way to update high-quality 3-D maps used in neuronavigation.
Occurrence of a Glioblastoma-associated Tenascin-C Isoform in Cerebral Cavernomas and Neighboring Vessels
Authors: Viale Giuseppe L. , Castellani Patrizia , Dorcaratto Alessandra , Pau Antonio , Sehrbundt Elke , Siri Annalisa , Birò Attila , Zardi Luciano
Published: July 2004

OBJECTIVE:

Regrowth of cerebral cavernomas after apparently complete excision, de novo occurrence, and evidence of proliferation-related patterns raise the question as to their intrinsic growth potential. A particular isoform (Type III repeat c) of the glycoprotein tenascin-C (TN-C), typically associated with the vessels of anaplastic gliomas, is regarded as a marker of vascular proliferation in lesions growing within brain tissue. This study sought to ascertain whether this isoform is expressed in cerebral cavernomas to gain further insight into the growth potential of these lesions.

METHODS:

Sixteen cerebral cavernomas and three fragments of normal brain underwent immunohistochemical examinations via two antibody fragments obtained by phage display technology. Previous characterization demonstrated that the fragment TN-12 recognizes the epidermal growth factor-like repeat, common to all TN-C isoforms. On the contrary, the fragment TN-11 was found to be highly specific for the Type III repeat c isoform.

RESULTS:

Accumulation of total TN-C was found in the vascular walls and in the interspaces between the blood cavities of all examined cavernomas. When the antibody fragment TN-11 was used, staining of the subendothelial layers occurred in both the bulk of the cavernomas and vessels of the white matter surrounding the lesions, but staining was absent in the control specimens.

CONCLUSION:

The distribution of the Type III repeat c isoform of TN-C, a putative marker of vascular proliferation, within cerebral cavernomas is consistent with the hypothesis of a growth potential of cerebral cavernomas. Enlargement of these lesions might involve recruitment of neighboring vasculature, which is possibly dependent on environmental conditions.
Exposure of the Dorsal Root Ganglion in Rats to Pulsed Radiofrequency Currents Activates Dorsal Horn Lamina I and II Neurons
Authors: Higuchi Yoshinori , Nashold Blaine S. , Sluijter Menno , Cosman Eric , Pearlstein Robert D.
Published: July 2004

OBJECTIVE:

Application of pulsed radiofrequency (RF) currents to the dorsal ganglion has been reported to produce long-term relief of spinal pain without causing thermal ablation. The present study was undertaken to identify spinal cord neurons activated by exposure of the dorsal ganglion to pulsed RF currents in rats.

METHODS:

Left-sided hemilaminectomy was performed in adult Sprague-Dawley rats to expose the C6 dorsal root ganglion. An RF electrode (0.5 mm diameter) with a thermocouple for temperature monitoring was positioned on the exposed ganglion, and rats were assigned to one of three treatment groups: pulsed RF treatment (20 ms of 500-kHz RF pulses delivered at a rate of 2 Hz for 120 s to produce tissue heated to 38°C), continuous RF (continuous RF currents for 120 s to produce tissue heated to 38°C), or sham treatment (no RF current; electrode maintained in contact with ganglion for 120 s).

RESULTS:

Treatment with pulsed RF but not continuous RF was associated with a significant increase in the number of cFOS-immunoreactive neurons in the superficial laminae of the dorsal horn as observed 3 hours after treatment.

CONCLUSION:

Exposure of the dorsal ganglion to pulsed RF currents activates pain-processing neurons in the dorsal horn. This effect is not mediated by tissue heating.
Intraparenchymal Tension Pneumatocele Complicating Frontal Sinus Osteoma: Case Report
Authors: Johnson David , Tan Leong
Published: July 2004

OBJECTIVE AND IMPORTANCE

A relatively rare condition of intraparenchymal tension pneumatocele secondary to a frontal sinus osteoma eroding posteriorly and breaching dura mater is described. The scanty body of literature on this subject is briefly summarized, and the importance of this condition as a result of its life-threatening but readily treatable intracranial mass effect is outlined.

CLINICAL PRESENTATION

The patient presented with acute deterioration in conscious state and lateralizing signs from the mass effect of gas under tension. Two weeks earlier, he had experienced vague and subtle changes in personality noticeable only to his family.

INTERVENTION

The patient was cured by a frontal craniotomy, partial excision of the osteoma, and suture repair of the dural defect after evacuation of the pressurized air cavity.

CONCLUSION:

This rare condition should be urgently treated in the event of acute deterioration. To prevent a life-threatening situation from arising, elective surgery should be considered for patients known to have air sinus osteomas that are at risk of erosion into the cranial cavity.
Intracranial Aneurysm and Vasculopathy after Surgery and Radiation Therapy for Craniopharyngioma: Case Report
Authors: Pereira Paulo , Cerejo Antonio , Cruz Joaquim , Vaz Rui
Published: July 2004

OBJECTIVE AND IMPORTANCE:

This case report illustrates the possible occurrence of intracranial aneurysms after surgery and radiation-induced vasculopathy.

CLINICAL PRESENTATION:

An internal carotid bifurcation aneurysm was diagnosed in a 19-year-old woman in a routine follow-up examination by magnetic resonance imaging 5 years after subtotal removal of a giant cystic craniopharyngioma treated by postoperative external radiotherapy. The presence of the aneurysm was confirmed by angiography.

INTERVENTION:

It was decided to treat the aneurysm by embolization with Guglielmi detachable coiling. However, at the beginning of the procedure, a few weeks after the diagnosis, a dramatic reduction in the carotid artery blood flow was observed, along with signs of thrombosis inside the aneurysm. In light of these findings, the procedure was aborted. Four months later, another angiographic examination confirmed the exclusion of the aneurysm and compensatory flow through the external carotid artery.

CONCLUSION:

During the assessment of patients who have undergone postoperative radiotherapy, the potential for the development of aneurysms and radiation-induced vasculopathy exists and should be kept in mind. Considering the potential for spontaneous thrombosis of these aneurysms, cautious judgment is recommended before making a decision to treat them.
Trochlear Nerve Neuroma Manifested with Intractable Atypical Facial Pain: Case Report
Authors: Veshchev Igor , Spektor Sergey
Published: July 2004

OBJECTIVE AND IMPORTANCE:

Trochlear nerve neuromas are extremely rare. Seventeen surgical cases of this pathological condition have been reported in the English literature. The presented case is distinct from previous reports.

CLINICAL PRESENTATION:

A 26-year-old woman presented with atypical facial pain. The neurological examination results were normal. Magnetic resonance imaging revealed a left parasellar mass.

INTERVENTION:

A left pterional craniotomy was performed, providing access to the left parasellar area. After incision of the tentorial edge, the tumor was observed to originate from the short segment of the trochlear nerve that runs between the tentorial leaves. The neuroma was totally removed.

CONCLUSION:

The facial pain resolved immediately after surgery. Although facial dysesthesias have been noted among patients with trochlear nerve neuromas, here the atypical facial pain was the only clinical manifestation. In all previously reported cases, neuromas originated from the cisternal segment of the trochlear nerve (always before the site of nerve entrance into the tentorial leaves) and expanded mainly into the prepontine and interpeduncular cisterns. Subtemporal and suboccipital approaches were used. In this case, the tumor arose from the short segment of the nerve running between the tentorial leaves. The tumor did not extend either into the ambient cistern or into the cavernous sinus but did involve the parasellar area. A pterional approach was appropriate for tumor removal. A trochlear nerve neuroma should be considered as a potential cause of atypical facial pain.
Intraoperative Assessment of Aneurysm Clipping Using Magnetic Resonance Angiography and Diffusion-weighted Imaging: Technical Case Report
Authors: Sutherland Garnette R. , Kaibara Taro , Wallace Carla , Tomanek Boguslaw , Richter Marlene
Published: July 2004

OBJECTIVE AND IMPORTANCE:

To use intraoperative magnetic resonance imaging, including magnetic resonance angiography and diffusion-weighted imaging, to monitor the surgical treatment of a patient with an intracranial aneurysm.

TECHNIQUE:

Intraoperative imaging was performed with a ceiling-mounted, mobile, 1.5-T magnet (developed in collaboration with Innovative Magnetic Resonance Imaging Systems, Inc., Winnipeg, MB, Canada) that included high-performance 20-mT/m gradients. Pre- and postclipping, intraoperative, T1-weighted, angiographic and diffusion-weighted magnetic resonance images were obtained from a patient with an incidental, 8-mm, anterior communicating artery aneurysm.

RESULTS:

T1-weighted images demonstrated brain anatomic features, with visible shifts induced by surgery. Magnetic resonance angiography demonstrated the aneurysm and indicated that, after clipping, the A1 and A2 anterior cerebral artery branches were patent. Diffusion-weighted studies demonstrated no evidence of brain ischemia.

CONCLUSION:

For the first time, intraoperative magnetic resonance imaging has been used to monitor the surgical treatment of a patient with an intracranial aneurysm.
Management of Intraprocedural Arterial Thrombus in Cerebral Aneurysm Embolization with Abciximab: Technical Case Report
Authors: Alexander Michael J. , Duckwiler Gary R. , Gobin Y. Pierre , Viñuela Fernando
Published: July 2004

OBJECTIVE AND IMPORTANCE:

Thromboembolic complications after cerebral aneurysm treatment with Guglielmi detachable coils (Boston Scientific/Target, Fremont, CA) are not infrequent; in a University of California, Los Angeles institutional review of 720 treated aneurysms, thromboembolic complications occurred in 2.5% of cases. The development of intraluminal thrombus during the embolization procedure, however, may be diagnosed promptly and treated effectively with appropriate therapy. This report describes the use of intravenously administered abciximab for the treatment of intraprocedural arterial thrombus encountered during the coil embolization of a recently ruptured anterior communicating artery aneurysm.

CLINICAL PRESENTATION:

A 45-year-old man presented with severe headache 12 days before transfer to our institution. He had no neurological deficits at admission. Previous computed tomography of the brain demonstrated subarachnoid hemorrhage, and magnetic resonance angiography from the other institution demonstrated a 4-mm anterior communicating artery aneurysm.

INTERVENTION:

The patient underwent Guglielmi detachable coil embolization of the aneurysm under systemic heparinization. During the embolization, however, a thrombus developed in the proximal left A2 segment. The patient was given an intravenous infusion (20 mg) of abciximab for 10 minutes, and within 15 minutes dissolution of the thrombus was observed with no angiographic evidence of distal emboli. After reversal of general anesthesia, the patient exhibited minimal right leg weakness, which resolved within 1 hour.

CONCLUSION:

Abciximab may be a useful adjunct for endovascular treatment of patients with cerebral aneurysms in whom intraprocedural arterial thrombus is encountered.
Transvascular Coil Hooking Procedure to Retrieve an Unraveled Guglielmi Detachable Coil: Technical Note
Authors: Raftopoulos Christian , Goffette Pierre , Billa Rudolf F. , Mathurin Pierre
Published: July 2004

OBJECTIVE:

A patient with an anterior communicating artery aneurysm was treated by use of endovascular coiling, and a Guglielmi detachable coil (Boston Scientific/Target, Fremont, CA) fractured distal to its connection to the delivering catheter. The unraveled coil floated out from the aneurysm to extend into the bifurcation of the left middle cerebral artery. We describe the microsurgical procedure used to retrieve the coil after an endovascular approach failed.

METHODS:

The left anterior cerebral artery was punctured just below the aneurysm neck, and a titanium microhook was introduced to anchor the coil and pull it out. Slight traction was exerted before sectioning the coil to avoid protrusion of the stump into the parent vessel.

RESULTS:

The unraveled coil was removed in totality without permanent morbidity.

CONCLUSION:

This report describes the case of a rare complication of coil embolization treated with a minimal transarterial coil hooking procedure.
Optic Nerve Sheath Meningiomas: Visual Improvement after Stereotactic Radiotherapy
Authors: Liu James K. , Forman Scott , Hershewe Gerard L. , Moorthy Chitti R. , Benzil Deborah L.
Published: July 2004

OBJECTIVE:

The management of primary optic nerve sheath meningioma (ONSM) is controversial. Surgery often results in postoperative blindness in the affected eye and thus has been abandoned as a treatment option for most patients. When these tumors are left untreated, however, progressive visual impairment ensues, which also leads to blindness. Recently, radiation therapy has gained wider acceptance in the treatment of these lesions. Experience with stereotactic radiotherapy (SRT) in the treatment of ONSMs is limited because of the rare incidence of this tumor. We present a series of patients with ONSM who were treated with SRT.

METHODS:

Five patients (three women, two men), ranging in age from 40 to 73 years, presented with progressive visual loss with decreased visual field, visual acuity, and color vision affecting six eyes (one patient had tumor involving both optic nerves). One patient also presented with proptosis and diplopia. Five eyes had functional residual vision (range, 20/20 to 20/40), and one eye was completely blind. All five patients were diagnosed clinically and radiographically to have an ONSM. Three were intraorbital, one was intracanalicular as well as intraorbital, and one was a left ONSM extending through the optic foramen into the intracranial space and involving the right optic nerve. The five functional eyes were treated with SRT by use of 1.8-Gy fractions to a cumulative dose of 45 to 54 Gy.

RESULTS:

Follow-up ranged from 1 to 7 years, and serial magnetic resonance imaging revealed no changes in the size of the tumor in all five patients. Four patients experienced dramatic improvement in visual acuity, visual field, and color vision within 3 months after SRT. One patient remained stable without evidence of visual deterioration or disease progression. None had radiation-induced optic neuropathy.

CONCLUSION:

SRT may be a viable option for treatment of primary ONSM in patients with documented progressive visual deterioration, and it may be effective in improving or stabilizing remaining functional vision.
Volumetric Stereotaxy and the Supratentorial Occipitosubtemporal Approach in the Resection of Posterior Hippocampus and Parahippocampal Gyrus Lesions
Authors: Russell Stephen M. , Kelly Patrick J.
Published: July 2004

OBJECTIVE:

Resection of intracranial tumors in the posterior hippocampus and the parahippocampal gyrus can be associated with significant morbidity because of the parenchymal resection and the cortical retraction often required in gaining access to this infrequently explored region. With the use of image guidance, the occipitosubtemporal (OST) approach requires neither lateral cortical resection nor the placement of brain retractors to gain surgical access to the posterior hippocampus and the parahippocampal gyrus, and this approach is associated with a high rate of gross total tumor resection.

METHODS:

The computer-assisted volumetric stereotactic OST approach was used to resect 40 posterior hippocampus and parahippocampal gyrus tumors in 34 consecutive patients during an 8-year period. Patient, radiographic, and surgical outcome data were collected retrospectively.

RESULTS:

The series included operations in 25 men and 15 women, and the patients' average age was 40.3 years (range, 15–69 yr). Twenty-five of the 40 procedures were performed to remove lesions in the dominant hemisphere, and previous craniotomies for resection had been performed in 12 of 40 cases. In 38 of 40 cases, histopathological analysis revealed a glial neoplasm, and 50% of these tumors were high-grade lesions. Preoperatively, 23 patients were neurologically intact before 40 procedures, whereas visual field deficits were noted in 7 patients, mild hemiparesis was documented in 4 patients, and other neurological deficits were present in 9 patients. An excellent outcome (Glasgow Outcome Scale Grade 5) was noted after 38 (95%) of the 40 computer-assisted volumetric stereotactic OST procedures. Permanent postoperative hemiparesis (Glasgow Outcome Scale Grade 4) occurred after one procedure, and a second patient, despite being neurologically unchanged postoperatively and despite having had an optimal tumor resection, died on postoperative Day 33 (Glasgow Outcome Scale Grade 1). Complete resection of the preoperatively defined tumor volume was noted on postoperative gadolinium-enhanced magnetic resonance imaging examinations after 39 (97.5%) of the 40 procedures. The average duration of clinical follow-up was 15.9 months (range, 0.5–67 mo).

CONCLUSION:

We think that the OST approach is well suited to the resection of tumors in the posterior hippocampus and the parahippocampal gyrus. By allowing the neurosurgeon to avoid unnecessary brain resection and retraction, this approach reduces the risk of injury to important lateral temporal and occipital lobe cortex and tracts. In addition, the resection of a posterior hippocampus or parahippocampal gyrus mass with the OST approach relieves temporal horn entrapment. Computer-assisted volumetric stereotaxy helps the neurosurgeon to maintain precise spatial and anatomic orientation and accurately delineates the margin between the tumor and the surrounding neural tissue.
Natural History of Tethered Cord in Patients with Meningomyelocele
Authors: Phuong Loi K. , Schoeberl Kimberly A. , Raffel Corey
Published: July 2004

OBJECTIVE:

The purpose of this study was to describe the natural history of tethered cord in patients who have undergone meningomyelocele repair.

METHODS:

We performed a retrospective review of 45 patients with a history of neonatal meningomyelocele repair who subsequently developed symptoms of tethered cord. Symptoms of tethered cord in this cohort consisted of the development of bladder spasticity or orthopedic foot deformity. None of these patients were treated with cord untethering; instead, they were treated symptomatically.

RESULTS:

On follow-up, 40 (88.9%) of these patients subsequently required additional orthopedic or urological procedures because of further symptoms of tethered cord. The incidence of progression of tethered cord syndrome is 27.5, 40, and 60% at 1, 2, and 5 years, respectively.

CONCLUSION:

Although this study does not address the question whether cord untethering will prevent further symptom development, these results do provide a strong rationale for consideration of an untethering procedure in patients with repaired meningomyelocele at the time of the onset of symptoms of tethered cord.
Clinical Utility of Quantitative Cerebral Blood Flow Measurements during Internal Carotid Artery Test Occlusions
Authors: Marshall Randolph S. , Lazar Ronald M. , Young William L. , Solomon Robert A. , Joshi Shailendra , Duong D. Hoang , Rundek Tanja , Pile-Spellman John
Published: July 2004

OBJECTIVE:

Internal carotid artery (ICA) balloon test occlusions (BTOs) are performed in the angiography suite to predict whether the patient has adequate collateral circulation to prevent stroke when permanent ICA occlusion (PCO) is required for treatment. Although many criteria have been proposed to facilitate predictions of stroke risk after PCO, no BTO techniques have been subjected to predictive validity testing in outcome studies. We describe a prospective case series study that tests the predictive validity of quantitative cerebral blood flow (CBF) measurements during ICA BTO.

METHODS:

Thirty-three patients with clinical indications for PCO underwent ICA BTO and then PCO. During BTO, standard neurological examinations, sustained-attention testing, and quantitative CBF measurements were performed. Two scalp scintillation detectors recorded washout data after ipsilateral intracarotid injection of xenon-133 through a port at the tip of the ICA-occluding balloon. Patients were monitored for the outcome measure of ipsilateral stroke for a mean of 34 months. The variables of quantitative CBF values, neurological examination results, sustained-attention test results, age, sex, and side of occlusion were examined with Kaplan-Meier log-rank tests, predictive validity analyses, and logistic regression analyses.

RESULTS:

CBF of less than 30 ml/100 g/min during BTO was the only variable that predicted stroke after PCO (log rank = 5.87, P = 0.015). The negative and positive predictive values for CBF findings were superior to those for standard neurological examination findings and sustained-attention test results. Age, sex, and side of occlusion did not predict stroke.

CONCLUSION:

Quantitative CBF testing, via the intracarotid injection technique, during BTO seems to be an important predictor of stroke after PCO.
Evaluation of Preoperative Administration of the Cyclooxygenase-2 Inhibitor Rofecoxib for the Treatment of Postoperative Pain after Lumbar Disc Surgery
Authors: Bekker Alex , Cooper Paul R. , Frempong-Boadu Anthony , Babu Ramesh , Errico Thomas , Lebovits Allen
Published: July 2004

OBJECTIVE:

A combination of analgesics with different mechanisms of action may improve postoperative pain control and reduce the incidence of side effects. This study was designed to assess the efficacy of preoperative administration of rofecoxib (Vioxx; Merck & Co., Inc., Somerset, NJ) in reducing pain and opioid requirements after single-level lumbar microdiscectomy.

METHODS:

A randomized, double-blind, placebo-controlled clinical trial was performed on 61 consenting patients who were considered American Society of Anesthesiologists Class I or II and who were scheduled for elective single-level lumbar microdiscectomy. Patients received either two doses of rofecoxib 50 mg or a placebo preoperatively. The outcome measures included morphine use in the postanesthesia care unit (PACU), discharge times, and side effect profile. Data were analyzed by use of independent sample t tests for continuous variables or χ2 tests for categorical variables. A P value of <0.05 was considered significant.

RESULTS:

The two groups were comparable with respect to patient characteristics, intraoperative opioid and hypnotic consumption, and duration of surgery. Patients in the rofecoxib group required significantly less morphine postoperatively. Significantly more patients in the placebo group reported pain scores greater than 7 at admission to the PACU. Time to first request for analgesia was shorter in the placebo group, but the difference did not reach statistical significance. There were no significant differences between groups in the incidence of nausea, time to discharge from the PACU, or hospital stay.

CONCLUSION:

Preoperative rofecoxib is effective in reducing postoperative narcotic consumption in patients undergoing lumbar laminectomy. The use of rofecoxib does not shorten PACU length of stay or hospital discharge time. These outcome measures depend on multiple administrative factors.
Choristoma of the Optic Nerve: Case Report
Authors: Giannini Caterina , Reynolds Carol , Leavitt Jacqueline A. , Schultz Gregory A. , Garrity James A. , Ebersold Michael J. , Scheithauer Bernd W. , Salomao Diva R.
Published: July 2004

OBJECTIVE AND IMPORTANCE:

Optic nerve choristoma is a rare lesion composed of adipose tissue and smooth muscle involving the optic nerve. Few cases have been reported.

CLINICAL PRESENTATION:

A 20-year-old woman presented with a history of slowly progressive visual loss in the left eye. On T1-weighted magnetic resonance imaging studies, after frequency-selective fat saturation, an optic nerve mass was detected at the level of the optic canal with signal characteristics suggesting the diagnosis of optic nerve lipoma.

INTERVENTION:

At left frontotemporal craniotomy, the intracranial optic nerve appeared thin and atrophic proximally and was covered by abundant adipose tissue distally. Because no cleavage plane could be identified between the fatty lesion and the optic nerve, which appeared splayed within the adipose tissue, the nerve was resected after an intraoperative biopsy. The presence of two heterotopic mesodermal elements, a rim of adipose tissue admixed with bundles of mature smooth muscle, extending into the nerve septa, warranted a diagnosis of optic nerve choristoma.

CONCLUSION:

Optic nerve choristoma is an uncommon optic nerve lesion. Even if imaging studies are highly suggestive of the diagnosis, pathological confirmation is required because of the high adipose tissue content in the majority of cases. The lesion, most likely malformative and nonneoplastic in nature, can be the cause of progressive visual loss.
Visual Field Deficit Caused by Vascular Compression from a Suprasellar Meningioma: Case Report
Authors: Bejjani Ghassan K. , Cockerham Kimberly P. , Kennerdell John S. , Maroon Joseph C.
Published: July 2004

OBJECTIVE AND IMPORTANCE:

Suprasellar meningiomas typically cause bitemporal hemianopsia by direct compression of the chiasm, its blood supply, or both. We report another mechanism for visual loss in suprasellar meningiomas, whereby compression by the suprajacent vascular complex is the offending agent.

CLINICAL PRESENTATION:

A 78-year-old woman with a suprasellar meningioma was diagnosed incidentally. During the follow-up period, she developed an inferior homonymous wedge defect consistent with superior compression, without any detectable radiological progression. It was decided to resect her tumor.

INTERVENTION:

The patient underwent a fronto-orbital approach for tumoral excision. Intraoperatively, a groove by the anterior cerebral artery complex was found along the superior surface of the chiasm. Postoperatively, the patient's visual deficit resolved.

CONCLUSION:

This case illustrates an unusual visual field deficit associated with a suprasellar meningioma. It also emphasizes the importance of frequent and careful visual field monitoring, which can precede radiological and symptomatic progression.
Ganglioglioma Presenting as a Meningioma: Case Report and Review of the Literature
Authors: Siddique Khawar , Zagardo Michael , Gujrati Meena , Olivero William
Published: July 2004

OBJECTIVE AND IMPORTANCE:

Gangliogliomas are intra-axial, avascular masses located predominately in the temporal lobe. A ganglioglioma that mimics a meningioma in that it is extra-axial and has a significant extracranial vascular supply has not been reported previously.

CLINICAL PRESENTATION:

A 12-year-old girl presented with a right temporoparietal mass. A neurological examination revealed nothing abnormal, and the girl's symptoms were limited to headaches.

INTERVENTION:

Magnetic resonance imaging revealed an extra-axial mass, and cerebral catheter angiography revealed a blood supply mainly from the posterior division of the right middle meningeal artery. Intraoperative findings confirmed the extra-axial location of the tumor, and histological analysis revealed that the tumor was a ganglioglioma.

CONCLUSION:

This report confirms that gangliogliomas can present as extra-axial, vascular masses that are similar to meningiomas.
De Novo Cerebral Arteriovenous Malformation: Case Report
Authors: Bulsara Ketan R. , Alexander Michael J. , Villavicencio Alan T. , Graffagnino Carmelo
Published: July 2004

OBJECTIVE AND IMPORTANCE:

Arteriovenous malformations (AVMs) are generally thought to have a congenital cause. This is the first report of an angiographically proven de novo cerebral AVM in an adult patient without previous vascular abnormality.

CLINICAL PRESENTATION:

A 26-year-old African-American woman developed multiple cranial nerve deficits and ataxia over the course of a few days after a streptococcal throat infection. T2-weighted magnetic resonance imaging scans revealed a hyperintense signal in the midbrain with extension into the diencephalon. A cerebral angiogram performed at that time to exclude vasculitis revealed normal cerebral vasculature. The patient was treated with corticosteroids, and symptoms resolved. Subsequently, at the age of 32, this patient presented with a severe headache and emesis, but with no focal neurological deficit.

INTERVENTION:

The patient's cranial computed tomographic and magnetic resonance imaging scans revealed a right posterior temporal intraparenchymal hemorrhage, and cerebral angiography revealed a new 3- by 2-cm AVM. The patient underwent microsurgical resection of the AVM and associated hematoma. Postoperative angiography revealed no evidence of residual AVM.

CONCLUSION:

This study details the case of a woman who developed a de novo cerebral AVM during a 6-year period. This report challenges the conventional belief that all AVMs have a congenital cause.
Long-term Results after Stereotactic Radiosurgery for Patients with Cavernous Malformations
Authors: Hasegawa Toshinori , McInerney James , Kondziolka Douglas , Lee John Y.K. , Flickinger John C. , Lunsford L. Dade
Published: July 2004

OBJECTIVE

Stereotactic radiosurgery has been used for patients with high-risk cavernous malformations of the brain. We performed radiosurgery for patients with symptomatic, imaging-confirmed hemorrhages for which resection was believed to be associated with high risk. This study examines the long-term hemorrhage rate after radiosurgery.

METHODS

We reviewed data obtained before and after gamma knife radiosurgery on 82 patients treated between 1987 and 2000. Most patients had multiple hemorrhages from brainstem or diencephalic cavernous malformations. Follow-up data were examined to identify hemorrhages, and an overall hemorrhage rate was calculated.

RESULTS

Observation before treatment averaged 4.33 years (range, 0.17–18 yr) for a total of 354 patient-years. During this period, 202 hemorrhages were observed, for an annual hemorrhage rate of 33.9%, excluding the first hemorrhage. Temporal clustering of hemorrhages was not significant. After radiosurgery, patient follow-up averaged 5 years (range, 0.42–12.08 yr), for a total of 401 patient-years. During this period, 19 hemorrhages were identified, 17 in the first 2 years posttreatment and 2 after 2 years. The annual hemorrhage rate was 12.3% per year for the first 2 years after radiosurgery, followed by 0.76% per year from Years 2 to 12. Eleven patients had new neurological symptoms without hemorrhage after radiosurgery (13.4%). The symptoms were minor in six of these patients and temporary in five.

CONCLUSION

Radiosurgery confers a reduction in the risk of hemorrhage for high-risk cavernous malformations. Risk reduction, although in evidence during initial follow-up, is most pronounced after 2 years. Given the difficulty of identifying high-risk patients, treatment after one major hemorrhage should be considered in selected younger patients. Such a strategy warrants further investigation.
Delayed Surgical Resection Reduces Intraoperative Blood Loss for Embolized Meningiomas
Authors: Chun Jay Y. , McDermott Michael W. , Lamborn Kathleen R. , Wilson Charles B. , Higashida Randall , Berger Mitchel S.
Published: July 2004

OBJECTIVE

Embolization before surgical resection of tumors has been demonstrated to reduce intraoperative blood loss, but the optimal time that should elapse between embolization and tumor resection has not been established. We evaluated whether immediate surgical resection (≤24 h) after embolization or delayed surgical resection (>24 h) was more effective in minimizing intraoperative blood loss.

METHODS

We retrospectively analyzed the records for 50 patients with meningiomas who underwent preoperative embolization between 1993 and 1999. We divided the patients into two groups, i.e., those who underwent surgical resection of their meningiomas ≤24 hours after embolization and those who underwent surgery more than 24 hours after embolization. The extent of embolization, intraoperative blood loss, duration of surgery, and length of the hospital stay were compared for the two groups. Postoperative pathological specimens were examined for assessment of the extent of vascularity and necrosis caused by embolization.

RESULTS

Intraoperative blood loss was greater for the immediate group than for the delayed group (29% with blood loss of >1000 ml [median, 475 ml] versus 0% with blood loss of >700 ml [median, 337.5 ml];P = 0.01). There were no statistically significant differences between the groups with respect to tumor volume, extent of embolization, degree of devascularization, necrosis, duration of surgery, or length of the hospital stay.

CONCLUSION

Contrary to previous studies that emphasized a need for tumor removal immediately after embolization, to prevent revascularization, surgical resection of meningiomas should be delayed more than 24 hours after embolization, because there is less intraoperative blood loss.
Trigeminal Nerve-Blood Vessel Relationship as Revealed by High-resolution Magnetic Resonance Imaging and Its Effect on Pain Relief after Gamma Knife Radiosurgery for Trigeminal Neuralgia
Authors: Brisman Ronald , Khandji Alexander G. , Mooij Robertus B.M.
Published: July 2004

OBJECTIVE

Blood vessel (BV) compression of the trigeminal nerve (Cranial Nerve [CN] V) is a common cause of trigeminal neuralgia (TN). High-resolution magnetic resonance imaging scans obtained during gamma knife radiosurgery (GKRS) in patients with TN may be used to analyze the BV-CN V relationship. Follow-up data from a large series of patients treated with GKRS for TN were used to provide information regarding the BV-CN V relationship and pain relief.

METHODS

T1-weighted, axial 1-mm-thick volume acquisition magnetic resonance imaging scans were obtained through the area of CN V at its exit from the brainstem after injection of 15 ml of gadolinium. The BV-CN V relationship on the symptomatic side that was treated with GKRS was categorized into the following groups: Group 1 (no close relationship), Group 2 (BV close to CN V but not touching it), and Groups 3 and higher (BV-CN V contact).

RESULTS

A total of 181 symptomatic nerves were studied in 179 patients with TN who were treated with GKRS. In BV-CN V Groups 1, 2, and 3 and higher, respectively, were 43 sides (24%), 31 sides (17%), and 107 sides (59%). In 100 sides where there was no surgical procedure before GKRS, 50% or greater pain relief was more likely in those with BV-CN V contact (51 [88%] of 58 sides) than in those without BV-CN V (29 [69%] of 42 sides) (P = 0.024). BV-CN V contact was observed more often in men (55 [69%] of 80 sides) than in women (52 [52%] of 101 sides) (P = 0.023) and more often in patients who had unilateral TN (104 [62%] of 169 patients) rather than bilateral TN (2 [20%] of 10 patients) (P = 0.016).

CONCLUSION

In patients who have not undergone previous surgery for TN, BV-CN V contact revealed by high-resolution magnetic resonance imaging may indicate a particularly favorable response to GKRS.
Long-term Hardware-related Complications of Deep Brain Stimulation
Authors: Oh Michael Y. , Abosch Aviva , Kim Seong H. , Lang Anthony E. , Lozano Andres M.
Published: July 2004

OBJECTIVE

To determine the incidence of long-term hardware-related complications of deep brain stimulation (DBS).

METHODS

The study design is a retrospective chart review of a single-surgeon, single-institution experience with DBS in 84 consecutive cases from 1993 to 1999. Only patients with a minimum follow-up of 1 year were considered. Five patients were excluded because trial stimulation failed to achieve pain relief (n = 4) or because the procedure was aborted owing to hemorrhage (n = 1). Seventy-nine patients received 124 permanent DBS electrode implants.

RESULTS

The mean follow-up period was 33 months, and the cumulative follow-up time was 217 patient-years or 310 electrode-years. Overall, 20 patients (25.3%) had 26 hardware-related complications involving 23 (18.5%) of the electrodes. There were 4 lead fractures, 4 lead migrations, 3 short or open circuits, 12 erosions and/or infections, 2 foreign body reactions, and one cerebrospinal fluid leak. The hardware-related complication rate per electrode-year was 8.4%. The most common complications were related to the electrode connectors. A significant finding was a high number of complications involving erosions or infections, which occurred in 7 of 12 instances as a late complication (beyond 12 mo).

CONCLUSION

Long-term follow-up reveals that hardware-related complications occur in a significant number of patients. Factors that lead to such complications must be identified and addressed to maximize the important benefits of DBS therapy.
Transfer of the Medial Pectoral Nerve: Myth or Reality?
Authors: Samardzic Miroslav , Grujicic Danica , Rasulic Lukas , Bacetic Dragoljub
Published: July 2004

OBJECTIVE

Transfer of the medial pectoral nerve is one of the most controversial procedures used to reinnervate the paralyzed upper arm because of brachial plexus spinal nerve root avulsion or directly irreparable proximal lesions of spinal nerves. The purpose of this study was to determine the value of this type of nerve transfer to the musculocutaneous and axillary nerves.

METHODS

The 25 patients included in the study comprised 14 patients who had nerve transfer to the musculocutaneous nerve and 11 who underwent nerve transfer to the axillary nerve. These patients’ functional recovery and the time course of their recovery were analyzed according to the type of transfer of one donor nerve or the donor nerve in combination with other donors.

RESULTS

Useful functional recovery was achieved in 85.7% of patients who had nerve transfer to the musculocutaneous nerve and in 81.8% of patients who underwent nerve transfer to the axillary nerve. There was no significant difference in results with regard to the type of nerve transfer and which recipient nerves were involved. A strong trend toward better results after procedures involving the use of a donor nerve combined with other donors was observed, however.

CONCLUSION

Our surgical results suggest that the transfer of the medial pectoral nerve to the musculocutaneous nerve and also to the axillary nerve may be a reliable and effective procedure.