bluuebunny/crossref_metadata_2025 huggingface dataset:
Transsphenoidal Approaches for the Extracapsular Resection of Midline Suprasellar and Anterior Cranial Base Lesions
Authors: Kaptain George J. , Vincent David A. , Sheehan Jason P. , Laws Edward R.
Published: July 2004

OBJECTIVE

The transsphenoidal approach is an effective method for treating tumors contained within the sella or extending into the suprasellar cistern. The technique of tumor dissection is predicated on preservation of the integrity of the diaphragma, i.e., intracapsular removal. Gross total extracapsular dissection may, however, be accomplished either by using a standard approach to the pituitary fossa or by extending the exposure to include removal of a portion of the planum sphenoidale and division of the superior intercavernous sinus.

METHODS

Included in this series were 14 patients with parasellar or sellar tumors with extension into the anterior fossa and/or suprasellar cistern. For 4 of 14 patients (29%), extracapsular access was gained by broaching the tumor capsule from within the pituitary fossa. For the remaining 10 of 14 patients (71%), the dura of the floor of the sella and the planum sphenoidale was exposed, using neuronavigation to verify the limits of bony dissection; extracapsular tumor resection was performed using the operating microscope and endoscopy as indicated. The dural defect was repaired with abdominal fat, the sellar floor and planum sphenoidale were reconstructed, and in selected cases a lumbar drain was placed.

RESULTS

Seven of 14 tumors (50%) were craniopharyngiomas, 3 of 14 (21%) were pituitary adenomas, and 2 of 14 (14%) were meningiomas. There was one case of lymphocytic hypophysitis and one yolk sac tumor. Gross total resection was possible in 11 of 14 cases (79%). Immediate postoperative visual function worsened in 2 of 14 cases (14%), improved in 3 of 14 cases (21%), and was stable in the remainder of cases. Postoperatively, 2 of 14 patients (14%) developed bacterial meningitis. Overt postoperative cerebrospinal fluid rhinorrhea was not observed.

CONCLUSION

Gross total extracapsular resection of midline suprasellar tumors via a transsphenoidal approach is possible but is associated with a higher risk of complications than is standard transsphenoidal surgery.
Surgery on Anterior Foramen Magnum Meningiomas Using a Conventional Posterior Suboccipital Approach: A Report on an Experience with 17 Cases
Authors: Goel Atul , Desai Ketan , Muzumdar Dattatraya
Published: July 2004

OBJECTIVE

The advantages of a posterior “conventional” suboccipital approach with a midline incision over lateral, anterolateral, and anterior approaches to anteriorly placed foramen magnum meningiomas are discussed.

METHODS

From 1991 to March 2000, 17 patients with foramen magnum meningiomas arising from the anterior or anterolateral rim of the foramen magnum underwent operations in the Department of Neurosurgery at King Edward Memorial Hospital and Seth G.S. Medical College. All patients were operated on in a semi-sitting position by use of a conventional suboccipital approach with a midline incision and extension of the craniectomy laterally toward the side of the tumor up to the occipital condyle.

RESULTS

The patients ranged in age from 17 to 72 years, and the tumors ranged in size from 2.1 to 3.8 cm. The intradural vertebral artery was at least partially encased on one side in eight patients and on both sides in two patients. The brainstem was displaced predominantly posteriorly in each patient. A partial condylar resection was performed in two cases to enhance the exposure. Total tumor resection was achieved in 14 patients, and a subtotal resection of the tumor was performed in the other 3 patients. In one patient, a small part of the tumor was missed inadvertently, and in the other two patients, part of the tumor in relation to the vertebral artery and posterior inferior cerebellar artery was deliberately left behind. After surgery, one patient developed exaggerated lower cranial nerve weakness. There was no significant postoperative complication in the remainder of the patients, and their conditions improved after surgery. The average length of follow-up is 43 months, and there has been no recurrence of the tumor or growth of the residual tumor.

CONCLUSION

From our experience, we conclude that a large majority of anterior foramen magnum meningiomas can be excised with a lateral suboccipital approach and meticulous microsurgical techniques.
Adjunctive Use of Endoscopy during Posterior Fossa Surgery to Treat Cranial Neuropathies
Authors: King Wesley A. , Wackym Phillip A. , Sen Chandranath , Meyer Glenn A. , Shiau John , Deutsch Harel
Published: July 2004

OBJECTIVE

The objective of this study was to determine the utility and safety of rigid endoscopy as an adjunct during posterior fossa surgery to treat cranial neuropathies.

METHODS

A suboccipital craniotomy was performed for 19 patients with non-neoplastic processes involving the Vth, VIIth, and/or VIIIth cranial nerves. Ten patients with trigeminal neuralgia (n = 8), hemifacial spasm (n = 1), or intractable tinnitus (n = 1) underwent primarily microvascular decompression procedures. One patient with geniculate neuralgia underwent nervus intermedius sectioning combined with microvascular decompression. Eight patients underwent unilateral vestibular nerve neurectomies for treatment of Ménière's disease. A 0- or 30-degree rigid endoscope was used in conjunction with the standard microscopic approach for all procedures.

RESULTS

All patients experienced resolution or significant improvement of their preoperative symptoms after posterior fossa surgery. The endoscope allowed improved definition of anatomic neurovascular relationships without the need for significant cerebellar or brainstem retraction. Cleavage planes between the cochlear and vestibular nerves entering the internal auditory canal and sites of vascular compression could not be microscopically observed for several patients; however, endoscopic identification was possible for all patients. There were no complications related to the use of the endoscope.

CONCLUSION

The rigid endoscope can be used safely during posterior fossa surgery to treat cranial neuropathies, and it allows improved observation of the cranial nerves, nerve cleavage planes, and vascular anatomic features without significant cerebellar or brainstem retraction.
Evidence of Increased Endothelial Cell Turnover in Brain Arteriovenous Malformations
Authors: Hashimoto Tomoki , Mesa-Tejada Ricardo , Quick Christopher M. , Bollen Andrew W. , Joshi Shailendra , Pile-Spellman John , Lawton Michael T. , Young William L.
Published: July 2004

OBJECTIVE

We hypothesized that human brain arteriovenous malformations (BAVMs) are nonstatic vascular lesions with active angiogenesis or vascular remodeling. To test this hypothesis, we assessed endothelial cell turnover in BAVMs.

METHODS

We identified nonresting endothelial cells by use of immunohistochemistry for the Ki-67 antigen. From archived paraffin blocks, we selected BAVM vessels without intravascular thrombosis or embolic material in areas nonadjacent to the nidus edge. For controls, we used 50- to 100-μm diameter cortical vessels from temporal lobe cortex removed for epilepsy treatment. The Ki-67 index was calculated as a percentage of Ki-67-positive endothelial cells. The data were analyzed by the nonparametric Mann-Whitney test and reported as mean ± standard deviation.

RESULTS

Thirty-seven specimens that met the above criteria were selected. There were 26 ± 15 vessels counted in each BAVM specimen versus 18 ± 5 in each control cortex (n = 5). The mean Ki-67 index was higher for BAVM vessels than control cortical vessels (0.7 ± 0.6 versus 0.1 ± 0.2%;P = 0.005), which represented an approximately seven-fold increase in the number of nonresting endothelial cells. In the BAVM group, there was a trend for younger patients to have a wider variation and higher Ki-67 index than older patients; no trend was evident in the control group.

CONCLUSION

Compared with control vessels, BAVM vessels have higher endothelial cell turnover, which suggests the presence of active angiogenesis or vascular remodeling in BAVMs.
Multiple Intracranial Aneurysms as Delayed Complications of an Atrial Myxoma: Case Report
Authors: Jean Walter C. , Walski-Easton Sabrina M. , Nussbaum Eric S.
Published: July 2004

OBJECTIVE AND IMPORTANCE

Atrial myxomas are rare cardiac tumors that may cause neurological complications; however, delayed neurological events after total tumor resection are rare. In this report, we present a patient who developed transient cerebral ischemic attacks and was found to have multiple intracranial aneurysms 5 years after successful resection of her atrial myxoma. At the time of myxoma resection, there were no neurological symptoms; at the time of presentation with transient ischemic attacks, there was no evidence of atrial recurrence.

CLINICAL PRESENTATION

A 32-year-old woman presented with five episodes of right arm and face paresthesia, each lasting 15 to 20 minutes, 5 years after successful resection of her atrial myxoma. Clopidogrel bisulfate therapy was initiated, with resolution of her symptoms. Angiography revealed multiple, peripherally located, fusiform cerebral aneurysms.

INTERVENTION

A left frontal craniotomy for resection and biopsy of one of the aneurysms was performed, to establish the diagnosis. Pathological analysis of the biopsied aneurysm provided evidence of direct atrial myxoma invasion and occlusion of the cerebral blood vessel.

CONCLUSION

Neurological symptoms may accompany or lead to the diagnosis of atrial myxoma. Rarely, as in this case, myxomatous aneurysms may develop years after definitive treatment of the primary tumor. Patients who have undergone successful resection of a left atrial myxoma may be at risk for delayed cerebral ischemia associated with aneurysm development, and this phenomenon must be considered for patients with neurological symptoms who present even years after myxoma removal. The natural history, pathophysiological features, and treatment dilemma of these aneurysms are discussed.
Arachnoid Cyst of the Craniocervical Junction: Case Report
Authors: Price Stephen J. , David Karoly M. , O'Donovan Dominic G. , Aspoas A. Robert
Published: July 2004

OBJECTIVE AND IMPORTANCE

An arachnoid cyst at the craniocervical junction presenting with obstructive hydrocephalus as a result of blockage of the outflow of the fourth ventricle is described. This is a very rare anatomic site, with only five other cases described in the literature.

CLINICAL PRESENTATION

A 37-year-old woman presented with a 9-month history of severe neck pain, persistent vomiting, visual disturbances, and numbness of the nose, cheek, and lips. She had severe bilateral papilledema on ophthalmoscopy. Magnetic resonance imaging revealed a midline cystic lesion extending down to C2.

INTERVENTION

The patient underwent posterior fossa craniectomy and excision of the arachnoid cyst. She made a full recovery and was asymptomatic at follow-up examination.

CONCLUSION

The symptomatology of these rare craniocervical arachnoid cysts and their development are discussed.
Adrenocorticotropic Hormone-producing Pituitary Tumors: 12- to 22-year Follow-up after Treatment with Stereotactic Radiosurgery
Authors: Höybye Charlotte , Grenbäck Eva , Rähn Tiit , Degerblad Marie , Thorén Marja , Hulting Anna-Lena
Published: July 2004

OBJECTIVE

To study retrospectively long-term outcomes of patients with adrenocorticotropic hormone-producing pituitary tumors that were treated with stereotactic Leksell gamma knife unit radiosurgery.

METHODS

Eighty-nine patients aged 5 to 67 years were treated between 1976 and 1985. Eighteen patients aged 18 to 68 years (mean age, 41 yr) were followed in detail. Fifteen patients were women. None had previously received conventional radiotherapy, but pituitary microsurgery had been performed in two patients, and one patient had had an adrenalectomy. In the remaining 15 patients, radiosurgery was the primary therapy.

RESULTS

Sixty-four patients had one stereotactic treatment, and 25 patients had two or more treatments. No complications were observed during treatment and the immediate follow-up period. At follow-up, 17 patients had died 1 to 20 years after the first treatment. No deaths were related to the treatment. In our 18 patients, the follow-up time after the first radiosurgical treatment was 12 to 22 years (mean follow-up period, 17 yr). Urinary cortisol levels gradually normalized in 83% of the patients. No recurrences were observed. Pituitary hormone insufficiencies developed in about two of every three patients and occurred even more than 10 years after treatment. Eight patients had transient hyperprolactinemia. The patients' vision and visual fields were unaffected, and none of them had signs of radiation-induced side effects such as brain tumors or brain necrosis.

CONCLUSION

Stereotactic radiosurgery is a safe and effective method in the treatment of patients with adrenocorticotropic hormone-producing pituitary tumors, and the effect of treatment is long-lasting. Stereotactic radiosurgery is mainly a complement to microsurgery because of its gradually appearing effect and the occurrence of pituitary insufficiency. New pituitary deficiencies may be found more than 10 years after treatment.
Surgical Management of Isolated Hemangioblastomas of the Spinal Cord
Authors: Roonprapunt Chanland , Silvera V. Michelle , Setton Avi , Freed Diana , Epstein Fred J. , Jallo George I.
Published: July 2004

OBJECTIVE

Intramedullary hemangioblastomas are rare tumors, accounting for just 3% of all intraspinal neoplasms. The purpose of this study is to define the occurrence of isolated intramedullary hemangioblastomas and to analyze the role of the radiological studies and surgery for these lesions.

METHODS

The charts of 19 consecutive patients operated on for isolated spinal intramedullary hemangioblastoma were reviewed. Preoperatively, all patients underwent magnetic resonance imaging and nine underwent spinal angiography. For all patients, the surgical approach was via posterior laminectomy.

RESULTS

Our study sample comprised 6 women and 13 men, with an average age of 31.5 years (range, 16–75 yr). The mean prodrome was 20.8 months. Pain was the most common complaint. In all cases, the neoplasms were associated with a syrinx or edema. Gross total resection was achieved in all patients. At last follow-up examination (mean, 50.1 mo), 13 patients (68%) had improved and 6 patients (32%) had stabilized as compared with their preoperative clinical status.

CONCLUSION

Isolated intramedullary hemangioblastomas typically have an indolent clinical course. These tumors have characteristic imaging properties on magnetic resonance imaging and angiography. Surgical removal of these lesions results in excellent long-term functional outcome.
Nuances in Acoustic Neuroma Surgery
Authors: Malis Leonard I.
Published: July 2004

THIS ARTICLE DESCRIBES surgical methods developed during my resection of 600 acoustic neuromas, 599 of which were total removals. This series began in 1965, with the introduction of the surgical microscope and the development of microsurgical technique. In the 1960s, there was no established technology for the microsurgery of acoustic neuromas. Much of the work of the great early neurosurgeons—Cushing, Dandy, Olivecrona, and other remarkable pioneers—did not really apply. New approaches, solutions, and tools were introduced at that time, and there was a long, steep learning curve. I hope that some of the discussion herein makes learning easier for the new generation of neurosurgeons as they develop their own operative nuances.
Three-dimensional Computed Tomographic Cranial Base Measurements for Improvement of Surgical Approaches to the Petrous Carotid Artery and Apex Regions
Authors: Villavicencio Alan T. , Leveque Jean-Christophe , Bulsara Ketan R. , Friedman Allan H. , Gray Linda
Published: July 2004

OBJECTIVE

The bony and vascular anatomic features in the region of the petrous apex can vary significantly. These variations affect the operative view obtained via extended subtemporal or anterior transpetrosal approaches to cranial base lesions for individual patients. The goal of this study was to evaluate three-dimensional computed tomography as a means of obtaining detailed preoperative anatomic information regarding bony and vascular landmarks and spatial relationships in the region of the petrous carotid artery and petrous apex.

METHODS

We radiographically studied 15 patients (30 sides), using 0.8- to 1-mm-thick, reconstructed, computed tomographic images. Special attention was given to the course of the petrous carotid artery.

RESULTS

The petrous carotid artery was located lateral to the trigeminal impression. The size of the petrous apex medial to the horizontal petrous carotid artery was observed to be variable. The width of bone from the trigeminal impression to the wall of the internal auditory canal averaged 9.6 mm (range, 5.2–16.1 mm). A variable amount of bone overlying the internal auditory canal (4.5 mm) was also present. Multiple other relationships among key landmarks were quantified.

CONCLUSION

There is significant variability in the anatomic features of the petrous apex among patients. For each patient, detailed preoperative information regarding the amount of bone to be removed during a cranial base procedure can be obtained using three-dimensional computed tomography. This information may be critical for determination of the amount of extra exposure that can be achieved via an anterior petrosectomy for each patient.
Cellular Engineering: Molecular Repair of Membranes to Rescue Cells of the Damaged Nervous System
Authors: Borgens Richard B.
Published: July 2004

PURPOSE

The acute administration of hydrophilic polymers (polyethylene glycol) can immediately seal nerve membranes, preventing their continuing dissolution and secondary axotomy. Polymer application can even be used to reconnect, or fuse, the proximal and distal segments of severed axons in completely transected adult mammalian spinal cord.

CONCEPT

The sealing or fusion of damaged nerve membranes leads to a very rapid (minutes or hours) recovery of excitability in severely damaged nerve fibers, observed as a rapid return of nerve impulse conduction in vitro, as well as an in vivo recovery of spinal cord conduction and behavioral loss in spinal cord-injured adult guinea pigs.

RATIONALE

Surfactant application produces a rapid repair of membrane breaches through mechanisms of interaction between the polymers and the aqueous phase of damaged membranes, and their ability to insert into, or seal, the hydrophobic core of the axolemma exposed by mechanical damage.

DISCUSSION

This new technology applied to severe neurotrauma offers a clinically safe and practical means to rescue significant populations of spinal cord nerve fibers within 8 hours after damage—preventing their continued dissolution and secondary axotomy by secondary injury mechanisms. Application of this novel technology to other injuries to the peripheral and central nervous system is discussed, as well as a general application to soft tissue trauma.
Metastatic Hepatocellular Carcinoma Presenting as Epidural Hematoma: Case Report
Authors: McIver Jon I. , Scheithauer Bernd W. , Rydberg Charlotte H. , Atkinson John L.D.
Published: July 2004

OBJECTIVE AND IMPORTANCE

A case of acutely symptomatic epidural hematoma caused by metastatic hepatocellular carcinoma (HCC) to the cranium is reported. This is a rare case of metastatic HCC without known primary presenting as an epidural hematoma.

CLINICAL PRESENTATION

The patient presented with an acute onset of headache, aphasia, and right hemiparesis 2 weeks after he experienced minor trauma to the cranium. An emergency computed tomographic scan of the head revealed the presence of a left parietal epidural hematoma.

INTERVENTION

An emergency evacuation of the epidural hematoma was performed, and metastatic HCC was diagnosed.

CONCLUSION

The patient's neurological deficits were reversed with surgical intervention, and he is now undergoing palliative chemotherapy. This was the first clinical manifestation of HCC in this patient. This case reaffirms the neurosurgeon's role in the complex, multidisciplinary care of patients with craniospinal metastasis.
Accumulation of Intraventricular Fat in an Intracranial Epidermoid Tumor: Case Report
Authors: Kwon Taek-Hyun , Park Youn-Kwan , Chung Hung-Seob , Lee Hoon-Kap
Published: July 2004

OBJECTIVE AND IMPORTANCE

A fat component within the ventricles or subarachnoid space in fat-containing tumors such as an epidermoid or a dermoid has been observed in rare instances. However, there have been no reports regarding an increase in the size of such a fat component. We describe the case of an epidermoid tumor with intraventricular fat that showed an increase in size and amount.

CLINICAL PRESENTATION

A 26-year-old woman was admitted with headache and diplopia. Computed tomography and magnetic resonance imaging of the brain revealed a fat-containing suprasellar tumor and widespread fat globules in adjacent sulci and cisterns and within the frontal horn of the lateral ventricle.

INTERVENTION

The patient underwent a pterional craniotomy. Removal of the suprasellar tumor was nearly total. Histopathological examination revealed an epidermoid tumor. Sequential magnetic resonance imaging throughout the ensuing 65-month period revealed no evidence of tumor recurrence; however, the intraventricular fat remained and increased in size. The patient underwent surgery via the transcallosal approach at 69 months after the initial operation, and the presence of free-floating oily fat globules was confirmed.

CONCLUSION

In the case of a fat-containing tumor with free fat in the cerebrospinal fluid spaces, careful serial examination is necessary, with particular attention to the possibility of changes in size.
New Method for Obliterative Treatment of an Anterior Wall Aneurysm in the Internal Carotid Artery: Encircling Silicone Sheet Clip Procedure—Technical Case Report
Authors: Kurokawa Yasutaka , Wanibuchi Masahiko , Ishiguro Masanori , Inaba Ken-ichi
Published: July 2004

OBJECTIVE AND IMPORTANCE

Aneurysms on the anterior surface of the internal carotid artery (ICA) have been shown to be somewhat different from ordinary berry aneurysms because they are rather small, grow rapidly in a short time, and easily lead to rupture, especially during surgery. The most difficult problem is that this type of aneurysm cannot be eliminated easily by an ordinary clipping procedure without causing apparent arterial stenosis or occlusion.

CLINICAL PRESENTATION

A 52-year-old man experienced a subarachnoid hemorrhage because of a ruptured aneurysm located on the anterior surface of the ICA. The tiny aneurysmal body, which was covered with a layer of brain tissue, was successfully exposed. The ICA seemed to be atherosclerotic, and the aneurysmal portion was solitary and had a reddish color.

TECHNIQUE

A large silicone sheet encircling clip (Vascwrap; Mizuho Ikakogyo Co., Ltd., Tokyo, Japan) was selected for this patient. The proximal margin of the silicone sheet was incised with a V-shaped cut, and the middle part of the sheet, which covered the diagonal part of the ICA, was trimmed to make it shorter. The blade of the fenestrated clip was applied to obliterate the aneurysm and was attached to the normal arterial wall together with this modified Vascwrap sheet to create a small space between the normal arterial wall and the surrounding Vascwrap sheet. Then tiny pieces of Teflon fiber (E.I. duPont de Nemours and Co., Wilmington, DE) was inserted from both margins, and the whole Vascwrap sheet was sealed with fibrin glue to ensure good adhesion.

CONCLUSION

This method seemed adequate in treating this difficult aneurysm without causing postoperative regrowth or occlusion of the patient's ICA.
Easy Sellar Reconstruction in Endoscopic Endonasal Transsphenoidal Surgery with Polyester-Silicone Dural Substitute and Fibrin Glue: Technical Note
Authors: Cappabianca Paolo , Cavallo Luigi Maria , Mariniello Giuseppe , de Divitiis Oreste , Romero Alicia Del Carmen Becerra , de Divitiis Enrico
Published: July 2004

OBJECTIVE

To describe a simple method of sellar reconstruction after endoscopic endonasal transsphenoidal surgery that will allow rapid watertight closure of the sellar floor.

METHODS

A bent sheet of a polyester-silicone dural substitute, fashioned for this purpose with scissors, is introduced into the sella after removal of the lesion. Because of the consistency of the sheet, it opens spontaneously and becomes stuck. Autologous fat tissue or gelatin foam is positioned thereafter, followed by another layer of the dural substitute; a film of fibrin glue completes the sealing.

RESULTS

Fifteen patients underwent this method and no postoperative cerebrospinal leak or other complication was experienced.

CONCLUSION

This easy method of sellar reconstruction represents an effective and fast possibility to perform the final step of the endoscopic transsphenoidal procedure, which otherwise may cause maneuverability problems in the limited space of one nostril.
Image-guided Placement of Eye Muscle Electrodes for Intraoperative Cranial Nerve Monitoring
Authors: Alberti Olaf , Sure Ulrich , Riegel Thomas , Bertalanffy Helmut
Published: July 2004

OBJECTIVE

Monitoring of the oculomotor system during cranial base or brainstem surgery requires extraocular intraorbital insertion of electromyography electrodes. We investigated the use of image-guidance technology for anatomically correct intraorbital electrode placement.

METHODS

For neuronavigation, an optical tracking system was used in a standard fashion. Needle electrodes were inserted percutaneously into the lateral rectus, inferior rectus, and superior oblique muscle along the axis of a hand-held pointer or by means of an electrode applicator to allow direct tracking with the navigation system. Electromyographic monitoring was performed by multichannel recordings of free running or evoked activity from the selected muscles.

RESULTS

We have used this method in 10 patients; 5 had cranial base tumors and 5 underwent operations for brainstem lesions. No additional instruments or resources were required compared with the routine setup, and no intraorbital structures were injured. Successful monitoring of oculomotor, trochlear, or abducent nerve function was possible in each case.

CONCLUSION

This method may have the potential to increase the safety and success rate of intraoperative electro-ophthalmography during microsurgery focused on preservation of neurological function.
Clinical Validation of True Frameless Stereotactic Biopsy: Analysis of the First 125 Consecutive Cases
Authors: Paleologos Theophilos S. , Dorward Neil L. , Wadley John P. , Thomas David G.T.
Published: July 2004

OBJECTIVE

A lockable guide device, adjustable for positioning, was used to obtain samples for tissue analysis during brain biopsy procedures performed using an interactive image guidance system. Clinical validation of this technique, which was developed for true frameless stereotactic biopsies, and analyses of the histological yield, complication rate, and patient demographic characteristics for a large series of frameless stereotactic biopsies were the purposes of this study.

METHODS

Demographic, radiological, surgical, and clinical data were prospectively collected for a series of 125 frameless stereotactic biopsies performed using the technique described in detail previously.

RESULTS

Eighty-six procedures were magnetic resonance imaging-directed and 39 were computed tomography-directed. The mean diameter of the biopsied lesions was 36 mm, and the mean distance from the skin was 35.8 mm. Sixteen percent of the patients harbored multiple lesions, and 5.6% of the biopsied lesions were infratentorial. The mean operative time (including the entire anesthetic time) was 1.5 hours. The smear examination findings were corroborated by conclusive histological results in 96% of the cases, and definitive positive diagnoses were obtained in 122 cases (97.6%). Ten patients experienced surgical complications, but the sustained morbidity rate was 2.4% (including the death of a patient who was in critical clinical condition preoperatively and who died 2 mo later as a result of a chest infection; mortality rate, 0.8%).

CONCLUSION

This true frameless stereotactic biopsy technique was associated with low morbidity and mortality rates and an excellent diagnostic yield, with overall results at least as good as those observed for frame-based stereotaxy. The excellent accuracy results demonstrated previously and statistically significant reductions in operative time, as well as improved image presentation, target selection, and simplicity, support the use of this frameless stereotactic technique in preference to frame-based biopsy techniques.
Image-guided Hypo-fractionated Stereotactic Radiosurgery to Spinal Lesions
Authors: Ryu Stephen I. , Chang Steven D. , Kim Daniel H. , Murphy Martin J. , Le Quynh-Thu , Martin David P. , Adler John R.
Published: July 2004

OBJECTIVE

This article demonstrates the technical feasibility of noninvasive treatment of unresectable spinal vascular malformations and primary and metastatic spinal tumors by use of image-guided frameless stereotactic radiosurgery.

METHODS

Stereotactic radiosurgery delivers a high dose of radiation to a tumor volume or vascular malformation in a limited number of fractions and minimizes the dose to adjacent normal structures. Frameless image-guided radiosurgery was developed by coupling an orthogonal pair of x-ray cameras to a dynamically manipulated robot-mounted linear accelerator that guides the therapy beam to treatment sites within the spine or spinal cord, in an outpatient setting, and without the use of frame-based fixation. The system relies on skeletal landmarks or implanted fiducial markers to locate treatment targets. Sixteen patients with spinal lesions (hemangioblastomas, vascular malformations, metastatic carcinomas, schwannomas, a meningioma, and a chordoma) were treated with total treatment doses of 1100 to 2500 cGy in one to five fractions by use of image-guided frameless radiosurgery with the CyberKnife system (Accuray, Inc., Sunnyvale, CA). Thirteen radiosurgery plans were analyzed for compliance with conventional radiation therapy.

RESULTS

Tests demonstrated alignment of the treatment dose with the target volume within ± 1 mm by use of spine fiducials and the CyberKnife treatment planning system. Tumor patients with at least 6 months of follow-up have demonstrated no progression of disease. Radiographic follow-up is pending for the remaining patients. To date, no patients have experienced complications as a result of the procedure.

CONCLUSION

This experience demonstrates the feasibility of image-guided robotic radiosurgery for previously untreatable spinal lesions.
Cutaneous Necrosis after Superficial Temporal Artery-to-Middle Cerebral Artery Anastomosis: Is It Predictable or Avoidable?
Authors: Katsuta Toshiro , Inoue Tooru , Arakawa Shuji , Uda Ken
Published: July 2004

OBJECTIVE

This study was carried out to determine whether a relationship exists between cutaneous necrosis after superficial temporal artery-to-middle cerebral artery anastomosis and background risk factors or surgical methods, and to determine whether such necrosis is predictable or avoidable.

METHODS

Forty-seven patients (a total of 51 sides) with atherosclerotic lesions of the internal carotid artery or middle cerebral artery who underwent superficial temporal artery-to-middle cerebral artery anastomosis at the National Kyushu Medical Center Hospital between September 1, 1994, and August 31, 1999, were reviewed. Each procedure was analyzed to determine whether cutaneous necrosis was present postoperatively around the donor site, whether preexisting risk factors (hypertension, diabetes mellitus, hyperlipidemia, ischemic heart disease, and arteriosclerosis obliterans) were present, and whether a flap or cutdown method or a single or double anastomosis was performed.

RESULTS

Postoperative necrosis was clearly related to arteriosclerosis obliterans (P < 0.003). The tendency for a relationship between necrosis and smoking was noted. Although statistical analysis failed to demonstrate a significant difference, necrosis was found with the flap method but not with the cutdown method.

CONCLUSION

Further study is needed using greater numbers to clarify the relationship between the surgical method and the presence of necrosis. To prevent cutaneous necrosis, however, it may be preferable to use the cutdown method in patients with the preexisting risk factors of arteriosclerosis obliterans or in smokers.
Transsylvian Keyhole Functional Hemispherectomy
Authors: Schramm Johannes , Kral Thomas , Clusmann Hans
Published: July 2004

OBJECTIVE

To describe the technical steps, advantages, and limitations of a quicker, minimal-exposure, functional hemispherectomy procedure developed from a hemispherical deafferentation technique previously described.

METHODS

The surgical approach using the transsylvian/transsulcal passage to the ventricular system, with the anatomic orientation points and key features for planning of the small trepanation, is described. Through a linear incision, a craniotomy (4 × 4 to 4 × 5 cm) is placed over the sylvian fissure. Transsylvian exposure of the circular sulcus allows transcortical exposure of the entire ventricular system, from the frontal horn to the temporal horn encircling the insular cortex. The frontobasal and mesial white matter is disconnected via the intraventricular approach, with a callosotomy. An amygdalohippocampectomy completes the dissection. The experience with 20 patients who were treated using the transsylvian keyhole hemispherectomy technique is summarized.

RESULTS

The operation time was significantly shorter (mean, 3.6 h) than with the Rasmussen technique (mean, 6.3 h) and 25% shorter than with the transcortical perisylvian technique (mean, 4.9 h). The proportion of patients requiring blood replacements was lower (15 versus 58%), as was the mean amount of transfused blood. The mean follow-up period was 46 months; 88% of patients were in Engel Outcome Class I, 6% in Class III, and 6% in Class IV.

CONCLUSION

The transsylvian keyhole procedure has been demonstrated to further reduce operation time and the need for blood replacement. It is most easily performed in cases with enlarged ventricles or perinatal ischemic cysts and is not recommended for hemimegalencephaly. The immediate seizure relief was satisfying. This minimal-exposure approach seems to be a satisfying alternative among possible functional hemispherectomy procedures.
Carotid Endarterectomy: Can We Select Surgical Candidates at High Risk for Stroke and Low Risk for Perioperative Complications?
Authors: Lanzino Giuseppe , Couture Daniel , Andreoli Alvaro , Guterman Lee R. , Hopkins L. Nelson
Published: July 2004

DESPITE EVIDENCE OF the efficacy of carotid endarterectomy from the large randomized multicenter trials completed in the 1990s, the physician who treats patients with carotid artery stenosis still is faced with a difficult management decision. More recently, subgroup analyses have been conducted of asymptomatic and symptomatic patients enrolled in these trials to identify clinical and radiological factors that increase the rates of morbidity and mortality associated with surgery, as well as those that increase the risk of stroke without surgery. Knowledge of these factors is important to recommend the best course of action for the individual patient. In this article, we summarize the conclusions of some of the subgroup analyses from the major carotid endarterectomy trials.
Unusual Brain Metastases from Papillary Thyroid Carcinoma: Case Report
Authors: Aguiar Paulo H. , Agner Celso , Tavares Fernanda R. , Yamaguchi Nise
Published: July 2004

OBJECTIVE AND IMPORTANCE

Brain metastases from papillary carcinoma of the thyroid gland are unusual. No consensus regarding management has yet been reached. We report a case, review the current literature, and explain our approach on the basis of clinical, pathological, and radiological data.

CLINICAL PRESENTATION

A 33-year-old woman presented with signs of intracranial hypertension. The diagnostic evaluation included chest tomography, head computed tomography, brain magnetic resonance imaging with and without contrast enhancement, total-body scanning, and cerebral scintigraphy. Multiple supratentorial lesions and one right cerebellopontine angle lesion were observed. Histopathological analysis of the surgical specimen confirmed papillary carcinoma of the thyroid gland.

INTERVENTION

A ventriculoperitoneal shunt was placed and a right suboccipital craniotomy was performed, with complete removal of the cerebellopontine angle tumor. Total-brain irradiation with 40 Gy/lesion followed the initial operation. One year after surgery, the patient presented with signs of increased intracranial pressure. A new left frontal lobe lesion with massive peritumoral edema was identified on magnetic resonance imaging scans. The edema was treated clinically and a left frontal craniotomy was performed, with complete resection of the tumor. The patient is currently faring well, with residual expressive aphasia.

CONCLUSION

Surgery followed by radiotherapy seems to be a good alternative for the treatment of this specific type of metastasis. Thorough clinical and radiological evaluation, followed by genetic analysis of the surgical specimen, particularly with respect to the potential for tumor invasion under specific conditions, is recommended. The information obtained contributes to better management and better overall long-term outcomes for these patients.
Peritumoral Brain Edema in Intracranial Meningiomas: Effects of Radiological and Histological Factors
Authors: Tamiya Takashi , Ono Yasuhiro , Matsumoto Kengo , Ohmoto Takashi
Published: July 2004

OBJECTIVE

We examined the radiological and histological features influencing the development of peritumoral brain edema (PTBE) among patients with meningiomas.

METHODS

Factors causing PTBE were retrospectively analyzed for 125 patients with primary intracranial meningiomas. These factors included tumor size, tumor location, brain-tumor interface, signal intensity on T2-weighted scans, contrast enhancement, and cyst formation (as observed on magnetic resonance imaging scans), as well as tumor vascularity and blood supply (as observed in digital subtraction angiography studies). We defined the edema/tumor volume ratio as the edema index, and we used this index to evaluate PTBE.

RESULTS

A relationship between the tumor size and the volume of PTBE was observed. Convexity and middle fossa meningiomas demonstrated the greatest increases in mean edema indices. Meningothelial, anaplastic, microcystic, and angiomatous subtypes exhibited higher edema indices than did other types. Multivariate analysis demonstrated two significant radiological factors: cortical penetration (as defined by the disappearance of the arachnoid layer on magnetic resonance imaging scans) (relative risk, 2.067;P = 0.0148) and vascular supply from the pial-cortical arteries (as observed on angiograms) (relative risk, 2.087;P = 0.0082).

CONCLUSION

Tumor infiltration into adjacent brain parenchyma and a pial-cortical blood supply are critical factors for the development of PTBE among patients with meningiomas.
Percutaneous Transpedicular Polymethylmethacrylate Vertebroplasty for the Treatment of Spinal Compression Fractures
Authors: Amar Arun Paul , Larsen Donald W. , Esnaashari Nasrin , Albuquerque Felipe C. , Lavine Sean D. , Teitelbaum George P.
Published: July 2004

OBJECTIVE

To assess the safety, feasibility, and clinical outcome of percutaneous transpedicular polymethylmethacrylate vertebroplasty (PTPV) for the treatment of spinal compression fractures causing refractory pain.

METHODS

We retrospectively reviewed a consecutive group of patients undergoing PTPV at our institution between April 1998 and January 2001. Outcome measures included analgesic requirements, ambulatory status, sleep comfort, and overall quality of life 2 weeks after the procedure.

RESULTS

A total of 97 patients (73 women and 24 men) underwent 258 PTPV procedures during 133 treatment sessions. The mean age was 76 years (range, 42–99 yr). The mean duration of follow-up was 14.7 months (range, 2–35 mo). Most of the patients had osteoporotic compression fractures, although some had osteolytic malignancies. Complete follow-up was obtained in 81 patients (84%). Narcotic and analgesic usage decreased in 63% of patients, increased in 7%, and remained the same in 30%. Ambulation and mobility were improved in 51%, worse in 1% and the same in 48%. One-half of the patients were able to sleep more comfortably after the procedure, whereas the other half remained the same. Most patients who reported no change in sleep or ambulation had experienced no impairment of these activities before PTPV. Overall, 74% of patients believed that PTPV significantly enhanced their quality of life and 26% reported no change. No patient was worse after PTPV. One patient with preexisting pneumonia died of respiratory failure after the procedure; another died of an acute stroke weeks later. One patient developed symptomatic pulmonary embolism of cement, and another developed transient quadriceps weakness from radiculopathy. Other complications were minor and infrequent. There were no infections.

CONCLUSION

PTPV provided significant relief in a high percentage of patients with refractory pain. PTPV is a safe and feasible treatment for patients with spinal compression fractures.
Intraoperative Magnetic Resonance Imaging to Determine the Extent of Resection of Pituitary Macroadenomas during Transsphenoidal Microsurgery
Authors: Bohinski Robert J. , Warnick Ronald E. , Gaskill-Shipley Mary F. , Zuccarello Mario , van Loveren Harry R. , Kormos Donald W. , Tew John M.
Published: July 2004

OBJECTIVE

Well-established surgical goals for pituitary macroadenomas include gross total resection for noninvasive tumors and debulking with optic chiasm decompression for invasive tumors. In this report, we examine the safety, reliability, and outcome of intraoperative magnetic resonance imaging (iMRI) used to assess the extent of resection, and thus the achievement of preoperative surgical goals, during transsphenoidal microneurosurgery.

METHODS

Our magnetic resonance operating room contains a Hitachi AIRIS II 0.3-T, vertical-field open magnet (Hitachi Medical Systems America, Inc., Twinsburg, OH). A motorized scanner tabletop moves the patient between the imaging and operative positions. For transsphenoidal surgery, the patient is positioned directly on the scanner tabletop so that the surgical field is located between 1.2 and 1.6 m from the magnet isocenter. At this location, the magnetic field strength is low (<20 G), thus permitting the use of many conventional surgical instruments. Thirty consecutive patients with pituitary macroadenomas underwent tumor resection in our magnetic resonance operating room by use of a standard transsphenoidal approach. After initial resection, the patient was advanced into the scanner for imaging. If residual tumor was demonstrated and deemed surgically accessible, the patient underwent immediate re-exploration.

RESULTS

iMRI was performed successfully in all 30 patients. In one patient, iMRI was used to clarify the significance of hemorrhage from the sellar region and resulted in immediate conversion of the procedure to a craniotomy. In the remaining 29 patients, initial iMRI demonstrated that the endpoint for extent of resection had been achieved in only 10 patients (34%) after an initial resection attempt, whereas 19 patients (66%) still had unacceptable residual tumor. All 19 of these latter patients underwent re-exploration. Ultimately, re-exploration resulted in the achievement of the planned endpoint for extent of resection in all of the 29 completed transsphenoidal explorations. Operative time was extended in all cases by at least 20 minutes.

CONCLUSION

iMRI can be used to safely, reliably, and objectively assess the extent of resection of pituitary macroadenomas during the transsphenoidal approach. The surgeon is frequently surprised by the extent of residual tumor after an initial resection attempt and finds the intraoperative images useful for guiding further resection.
Solitary Fibrous Tumor of the Orbit with Extraorbital Extension: Case Report
Authors: Hayashi Satoru , Kurihara Hideyuki , Hirato Junko , Sasaki Tomio
Published: July 2004

OBJECTIVE AND IMPORTANCE

Solitary fibrous tumors (SFTs) are rare tumors of mesenchymal origin that typically arise in the pleura. Only 24 cases of SFTs in the orbit have been reported, all located within the orbit and generally with a benign course. We report the first case of an orbital SFT with extraorbital extension and short-term regrowth.

CLINICAL PRESENTATION

A 54-year-old man presented with proptosis and double vision that had persisted for 7 months. The tumor extended from the right extraconal inferolateral orbit to the extradural middle cranial fossa and cavernous sinus, via the superior orbital fissure, on magnetic resonance imaging scans. Positron emission tomography with [18F]fluorodeoxyglucose demonstrated faint uptake in the orbital portion.

INTERVENTION

Resection of the tumor was performed twice, because of short-term regrowth of the residual tumor in the orbit. The histological diagnosis was a SFT. The MIB-1 labeling index was 7% and the mitotic count was 5 mitotic figures/10 high-power fields at the time of the second operation. These findings indicate the malignant nature of the tumor.

CONCLUSION

The natural history of SFTs of the orbit remains unclear, and the importance of careful and continued follow-up monitoring of the tumor should be emphasized.
Age and Radiation Response in Glioblastoma Multiforme
Authors: Barker Fred G. , Chang Susan M. , Larson David A. , Sneed Penny K. , Wara William M. , Wilson Charles B. , Prados Michael D.
Published: July 2004

OBJECTIVE

Advanced age is a strong predictor of shorter survival in patients with glioblastoma multiforme (GM), especially for those who receive multimodality treatment. Radiographically assessed tumor response to external beam radiation therapy is an important prognostic factor in GM. We hypothesized that older GM patients might have more radioresistant tumors.

METHODS

We studied radiographically assessed response to external beam radiation treatment (five-level scale) in relation to age and other prognostic factors in a cohort of 301 GM patients treated on two prospective clinical protocols. A total of 223 patients (74%) were assessable for radiographically assessed radiation response. A proportional odds ordinal regression model was used for univariate and multivariate analysis.

RESULTS

Younger age (P = 0.006), higher Karnofsky Performance Scale score before radiotherapy (P = 0.027), and more extensive surgical resection (P = 0.028) predicted better radiation response in univariate analyses. Results were similar when clinical criteria were used to classify an additional 61 patients without radiographically assessed radiation response (stable versus progressive disease). In multivariate analyses, age and extent of resection were significant independent predictors of radiation response (P < 0.05); Karnofsky Performance Scale score was of borderline significance (P = 0.07).

CONCLUSION

Older GM patients are less likely to have good responses to postoperative external beam radiation therapy. Karnofsky Performance Scale score before radiation treatment and extent of surgical resection are additional predictors of radiographically assessed radiation response in GM.