bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical and pathological effects of bromocriptine on prolactin-secreting and other pituitary tumors
Authors: Barrow Daniel L. , Tindall George T. , Kovacs Kalman , Thorner Michael O. , Horvath Eva , Hoffman James C.
Published: May 2009

✓ Bromocriptine inhibits prolactin secretion and causes size reduction of prolactin-secreting adenomas. The effect of the drug upon pituitary tumors other than prolactinomas is uncertain. The authors report a prospective series of 12 patients with pituitary macroadenomas in whom bromocriptine was administered for 6 weeks prior to transsphenoidal surgery. Five of the patients had computerized tomographic documentation of significant reductions in tumor size (Group A) and six had no change (Group B) during 3 and 6 weeks of bromocriptine administration. One patient who demonstrated size reduction in his tumor was not assigned to either group as he was treated with high-dose dexamethasone concurrently with the bromocriptine. Pathological examination (light and electron microscopy and immunocytochemistry) indicated that all Group A patients harbored tumors with prolactin granules whereas all Group B tumors lacked such granules. Adenoma cells in the responsive tumors were involuted with reduced cytoplasmic, nuclear, and nucleolar areas. Neither widespread cell necrosis, infarction, nor vascular injury was observed. Two of the five Group A patients discontinued bromocriptine prior to completion of the 6-week protocol and had a rapid return of their tumors to pre-treatment size.

Although bromocriptine has been reported to cause shrinkage of nonfunctional tumors, there was no radiological evidence of size reduction or pathological changes in the nonfunctional tumors of this series. Interestingly, serum levels of prolactin were modestly elevated (84 and 113 ng/ml) in two of the six Group B patients, an elevation due to stalk compression rather than secretion by adenoma cells. This finding underscores the fact that failure of bromocriptine to reduce pituitary tumor size in the presence of hyperprolactinema may occur because the tumor is other than a prolactinoma.

This is the first moderate-sized group of patients in whom pathological changes in responsive prolactinomas during bromocriptine therapy have been demonstrated. As bromocriptine is not tumoricidal, and thus not curative, there is insufficient evidence to recommend this drug as primary therapy for either prolactin-secreting or nonfunctional macroadenomas, but the drug may have potential as a preoperative adjunct to effect shrinkage of prolactinomas and theoretically, at least, make excision easier and possibly more complete.
Brachytherapy of recurrent malignant brain tumors with removable high-activity iodine-125 sources
Authors: Gutin Philip H. , Phillips Theodore L. , Wara William M. , Leibel Steven A. , Hosobuchi Yoshio , Levin Victor A. , Weaver Keith A. , Lamb Sharon
Published: May 2009

✓ Thirty-seven patients harboring recurrent malignant primary or metastatic brain tumors were treated by 40 implantations of high-activity iodine-125 (125I) sources. All patients had been treated with irradiation and most had been treated with chemotherapeutic agents, primarily nitrosoureas. Implantations were performed using computerized tomography (CT)-directed stereotaxy; 125I sources were held in one or more afterloaded catheters that were removed after the desired dose (minimum tumor dose of 3000 to 12,000 rads) had been delivered. Patients were followed with sequential neurological examinations and CT scans. Results of 34 implantation procedures were evaluable: 18 produced documented tumor regression (response) for 4 to 13+ months; five, performed in deteriorating patients, resulted in disease stability for 4 to 12 months. The overall response rate was 68%. In 11 patients, implantation did not halt clinical deterioration.

At exploratory craniotomy 5 to 12 months after implantation, focal radiation necrosis was documented in two patients whose tumor had responded initially and then progressed, and in three patients whose disease had progressed initially (four glioblastomas, one anaplastic astrocytoma); histologically identifiable tumor was documented in two of these patients. All improved after resection of the focal necrotic mass and are still alive 10, 15, 19, 24, and 25 months after the initial implantation procedure; only one patient has evidence of tumor regrowth. The median follow-up period after implantation for the malignant glioma (anaplastic astrocytoma and glioblastoma multiforme) group is 9 months, with 48% of patients still surviving. While direct comparison with the results of chemotherapy is difficult, results obtained in this patient group with interstitial brachytherapy are probably superior to results obtained with chemotherapy.
Treatment of pedicular fractures of the axis
Authors: Borne Guy M. , Bedou Gerard L. , Pinaudeau Magloire
Published: May 2009

✓ The authors report 18 cases of pedicular fractures of C-2. The characteristics of these fractures are discussed, and the authors conclude that these lesions are more correctly called “pedicular-isthmus” fractures. A technique of screw fixation of the pedicle is presented. This was found to be a simple and safe method of repair, giving consistently good anatomical and functional results.
Primary lymphoma of the central nervous system
Authors: Helle Todd L. , Britt Richard H. , Colby Thomas V.
Published: May 2009

✓ The authors present 22 cases of primary lymphoma of the central nervous system (CNS) from Stanford University Medical Center. Fifteen other published series comprising 400 patients with this disease are also reviewed. Males were affected more often than females. The majority of patients were in the sixth decade of life. The most common presenting symptoms were headache, nausea, vomiting, and mental status changes. The most common presenting signs were hemiparesis and papilledema. An elevated protein concentration was the most common cerebrospinal fluid (CSF) abnormality. The CSF cytology was rarely positive prior to surgery. If a mass was seen on computerized tomography, it always enhanced with infusion of contrast material. On angiography, the tumor was generally seen as an avascular mass. The most and least common sites of involvement supratentorially were the frontal and occipital lobes, respectively. Infratentorially, the cerebellum was most often involved. Histologically, the most common tissue type according to the Rappaport and Working Formulation systems were diffuse histiocytic lymphoma and immunoblastic lymphoma, respectively. Therapy primarily involved surgery for biopsy or subtotal resection and radiation therapy. The majority of patients died, and the median survival time of those dying was distinctly shorter than the follow-up period of those patients still alive. This difference in survival time suggests that primary CNS lymphoma consists of more than one disease group. Statistical analysis of our series showed those patients with either a diffuse mixed lymphoma histology or an infratentorial location of disease had a poorer prognosis. These two factors cannot totally account for the division of cases into separate survival-related groups.
Characteristics and use of ultra-long aneurysm clips
Authors: Sugita Kenichiro , Kobayashi Shigeaki , Inoue Toshiki , Takemae Toshiki
Published: May 2009

✓ Ultra-long aneurysm clips, 21 to 40 mm in length, are described, and their characteristics and application delineated. These clips have been used in 30 procedures for various kinds of aneurysms. They are useful not only for wide-necked and giant aneurysms but also for deeply located aneurysms such as those on the vertebrobasilar artery.
Cerebral air embolism occurring at angiography and diagnosed by computerized tomography
Authors: Voorhies Rand M. , Fraser Richard A. R.
Published: May 2009

✓ A case of air embolism complicating cerebral angiography is presented. The presence of the embolism was confirmed with high-resolution computerized tomography scans using appropriate window settings.
Progressive posttraumatic superior sagittal sinus thrombosis complicated by pulmonary embolism
Authors: Crimmins Timothy J. , Rockswold Gaylan L. , Yock Douglas H.
Published: May 2009

✓ A case of progressive posttraumatic superior sagittal sinus thrombosis is presented, with the complication of pulmonary embolism. A good clinical outcome followed treatment with barbiturate coma.
Diabetic polyradiculopathy simulating lumbar disc disease
Authors: Hirsh Leonard F.
Published: May 2009

✓ Most clinicians are aware of the common neurological effects of endocrine disorders. However, involvement of the spinal nerve roots is a poorly recognized complication of diabetes mellitus. Such involvement can closely simulate more common spinal diseases and thus lead to inappropriate therapy. Four cases of diabetic polyradiculopathy simulating lumbar disc disease are reported, and this distinctive entity is reviewed.
Postural fluctuation of hemifacial spasm
Authors: Moore A. Peter
Published: May 2009

✓ A patient is described who demonstrated an impressive fluctuation in the severity of hemifacial spasm with change in head position. Postmortem examination revealed a large fusiform aneurysm impinging on the facial nerve.
Intradural extramedullary tuberculoma of the cervical spine
Authors: Compton Jeff S. , Dorsch Nicholas W. C.
Published: May 2009

✓ A case is reported of a 45-year-old man who developed quadriplegia following a trivial motor-vehicle accident. Investigation including computerized tomography (CT) of the cervical spine revealed a large calcified lesion displacing the spinal cord and nerve roots, which proved to be a tuberculoma. The case is unusual in regard to the age of the patient, the size, location, and nature of the lesion, the mode of presentation, and the delineation of the lesion by CT scanning.
Intracranial actinomycoma with osteomyelitis simulating meningioma
Authors: Khosla Virender K. , Banerjee Ashru K. , Chopra Jagjit S.
Published: May 2009

✓ A rare case of actinomycotic osteomyelitis with an intracranial granuloma is presented. The computerized tomography findings are probably the first of their kind. Both the site of osteomyelitis and clinical presentation are unusual. The pertinent literature is reviewed.
Hyponatremia and natriuresis following subarachnoid hemorrhage in a monkey model
Authors: Nelson Paul B. , Seif Said , Gutai James , Robinson Alan G.
Published: May 2009

✓ A monkey model of subarachnoid hemorrhage (SAH) was used to study both the incidence of hyponatremia and natriuresis and the associated changes in antidiuretic hormone (ADH) secretion and salt and water balance. Following SAH, seven of nine monkeys became natriuretic and hyponatremic. The natriuretic period lasted an average of 4.4 ± 0.4 days. The mean nadir of serum sodium content was 125.7 ± 1.6 mEq/liter, and occurred on the average on the 5th day following SAH. The sodium balance after SAH was negative as compared to the preoperative positive sodium balance (p < 0.001). The plasma vasopressin level was usually elevated for a day following surgery, but there was no significant difference in the levels during the preoperative period and during the period of natriuresis following SAH. The daily urine output and aldosterone levels were not significantly different, and the plasma volume was slightly, but not significantly, decreased after SAH. Four of the animals that had a hyponatremic and natriuretic response following SAH showed a normal regulation of vasopressin in response to both a water challenge and hypertonic saline challenge. The three monkeys that underwent sham procedures did not become hyponatremic and natriuretic postoperatively. The sham-operated monkeys did not show significant differences in their plasma vasopressin levels, urine volume, plasma volume, and aldosterone levels following surgery. These observations are more consistent with primary natriuresis as the cause of hyponatremia rather than the syndrome of inappropriate secretion of ADH. The cause of the renal loss of sodium is not known, but the possibility of a brain natriuretic factor or an alteration in the neural control of the kidney should be considered.
Protective effect of lidocaine in acute cerebral ischemia induced by air embolism
Authors: Evans Delbert E. , Kobrine Arthur I. , LeGrys David C. , Bradley Mark E.
Published: May 2009

✓ To investigate possible approaches to the prevention and treatment of neural damage induced by air embolism and other forms of acute cerebral ischemia, a model was used in which cerebral air embolism was produced by infusion of air (0.4 ml) into a vertebral artery of chloralose-anesthetized cats. Neurological function was assessed by measuring cortical somatosensory evoked responses in a group of 10 untreated animals and in a group of eight animals pretreated with intravenous lidocaine (5 mg/kg). In the untreated group, the primary somatosensory amplitude was reduced to 28% ± 9% (mean ± standard error) of the value before air embolism, with a return to 60% ± 8% 1 hour and 73% ± 12% 2 hours after embolism. In the group pretreated with lidocaine, the primary somatosensory amplitude was reduced to 68% ± 9% of the value before air embolism, with a return to 92% ± 3% 1 hour and 97 ± 2% 2 hours after embolism. Pretreatment with lidocaine also greatly attenuated the acute hypertension and the increase in intracranial pressure following air embolism. These results demonstrate that pretreatment with intravenous lidocaine significantly reduces the neural decrement and increases the recovery of neural function after acute cerebral ischemia induced by air embolism.
Harrington rod stabilization for pathological fractures of the spine
Authors: Sundaresan Narayan , Galicich Joseph H. , Lane Joseph M.
Published: May 2009

✓ Nineteen patients with tumors involving the thoracolumbar spine were treated by Harrington rod stabilization following laminectomy. Sixteen patients had metastatic neoplasms, and three had primary tumors of the vertebral column. In five patients, extensive decompressive laminectomy and Harrington distraction rods to provide immediate stability were used as initial treatment; postoperative irradiation was then given. All five patients were ambulatory, and the four patients with preoperative pain all noted relief of pain following treatment. The remaining 14 patients had received radiation therapy to the spine prior to surgery; in these 14, indications for surgery included a combination of pain and weakness (10 patients), pain alone (two patients), or weakness alone (two patients). Of 12 patients with preoperative pain, after surgery pain relief was noted in nine patients, and eight were ambulatory. Major wound breakdowns occurred in two of the 14 patients who had received radiation prior to surgery. These results suggest that Harrington rod instrumentation is useful in providing postoperative stability and restoring alignment following laminectomy for tumors involving the spine, but carries an increased risk of wound-related complications if used in a previously irradiated region.
Radionuclide estimation of cerebrospinal fluid shunt flow
Authors: Kuruc Alvin , Treves Salvador , Welch Keasley , Merlino Denise
Published: May 2009

✓ Flow of cerebrospinal fluid through a surgically implanted valve may be estimated by analyzing the disappearance curve resulting from the injection of a radiotracer into the valve. The standard method for estimating flow assumes an exponential disappearance of the tracer from the valve. This method models the valve as a single well-mixed compartment. Experimental evidence, showing that estimates of flow were dependent upon the site of injection, is at variance with this assumption. An alternative method of analyzing the disappearance curves, based on the area to height ratio (A/H) of the curves, was found to be more consistent with the experimental evidence and resulted in greater precision than the exponential method. It was concluded that optimal results are obtained using the A/H method with a fixed injection technique.
Microsurgical anatomy of the region of the tentorial incisura
Authors: Ono Michio , Ono Makiko , Rhoton Albert L. , Barry Margaret
Published: May 2009

✓ The microsurgical anatomy of the tentorial incisura was evaluated in 25 adult cadavers using × 3 to × 40 magnification. The area surrounding the incisura is divided into the anterior, middle, and posterior incisural spaces. The anterior incisural space is located anterior to the brain stem and extends upward around the optic chiasm to the subcallosal area; the middle incisural space is located lateral to the brain stem and is intimately related to the hippocampal formation in the medial part of the temporal lobe; and the posterior incisural space is located posterior to the midbrain and corresponds to the region of the pineal gland and vein of Galen. The neural, cisternal, ventricular, and vascular relationships of each space were examined. The arterial relationships in the anterior incisural space and the venous relationships in the posterior incisural space are extremely complex, since the anterior incisural space contains all the components of the circle of Willis and the bifurcation of the internal carotid and basilar arteries, and the posterior incisural space contains the convergence of the internal cerebral and basal veins and many of their tributaries on the vein of Galen. The discussion reviews tentorial herniation and operative approaches to the incisura.
Surgical considerations in treatment of intraventricular cysticercosis
Authors: Apuzzo Michael L. J. , Dobkin William R. , Zee Chi-Shing , Chan James C. , Giannotta Steven L. , Weiss Martin H.
Published: May 2009

✓ Infestations of the human brain with the larval stage of Taenia solium, once an infrequent diagnosis in the United States, is now a more frequently encountered clinical entity especially in population centers with high immigrant flux. During a recent 5-year period 45 cases of intraventricular cysticercosis have been evaluated and treated. Modes of involvement included isolated cyst formation, ependymitis, or combinations of both. Evidence of associated parenchymatous involvement was present in 20% of cases. Sites of infestation included the lateral ventricle (five cases), third ventricle (12 cases), Sylvian aqueduct (four cases), and fourth ventricle (24 cases). Mean post-therapy follow-up periods for this series exceed 36 months. This experience indicates that direct excision is the treatment of choice for ventricular cystic lesions, but that management, operative planning, and expectations should be influenced by considerations of: 1) the potential for acute clinical deterioration (38%); 2) the potential for cyst migration; 3) attendant ependymitis, defined by computerized tomography or verified at surgery; 4) the potential for increase in cyst volume with local mass effect; 5) selection and institution of corridors of surgical access that establish alternative routes of cerebrospinal fluid flow; and 6) the possibility of cyst excision by a stereotaxic endoscopic procedure.
Recurrent subarachnoid bleeding in association with dural substitute
Authors: Simpson Donald , Robson Alastair
Published: May 2009

✓ Three cases of recurrent subarachnoid bleeding are reported. The hemorrhages occurred at intervals of up to 10 years after posterior fossa craniotomy with closure using grafts of Silastic dural substitute. In one case, reexploration showed that the hemorrhage had arisen from a neomembrane formed at the site of the dural substitute; in the others, circumstantial evidence suggested a similar pathology.
Transient neurological deficits secondary to saccular vertebrobasilar aneurysms
Authors: Steinberger Abe , Ganti S. Ramaiah , McMurtry James G. , Hilal Sadek K.
Published: May 2009

✓ Aneurysms have rarely been implicated as a possible cause of transient neurological deficits, and most reports of this phenomenon describe aneurysms in the anterior circulation. There is only one previous report of a saccular posterior circulation aneurysm associated with transient ischemic attacks. The authors document two cases of giant saccular vertebrobasilar artery aneurysms associated with transient neurological deficits.
Hemangioma calcificans
Authors: Harbaugh Robert E. , Roberts David W. , Fratkin Jonathan D.
Published: May 2009

✓ A 44-year-old woman presented with intraventricular hemorrhage and a calcified avascular mass lesion in the anterior third ventricle. This lesion proved to be a densely calcified variant of cavernous hemangioma, namely, hemangioma calcificans. Twelve previous cases of this lesion have been reported in the neurosurgical literature. Association with spontaneous intraventricular hemorrhage has not been previously reported. The clinical presentation, radiological appearance, surgical findings, and histopathology of this lesion are discussed and a brief review of the literature is presented.
Cerebellar mass caused by Candida species
Authors: Ilgren Edward B. , Westmorland Diana , Adams Christopher B. T. , Mitchell Robert G.
Published: May 2009

✓ The authors report a case of cerebellar pseudotumor caused by a Candida species without evidence of any underlying systemic disorder or extracranial disease. Total removal followed by treatment with amphotericin B resulted in a favorable outcome.
Ganglioglioma of the brain stem
Authors: Garcia Carlos A. , McGarry Paul A. , Collada Mauricio
Published: May 2009

✓ A case of brain-stem ganglioglioma is reported. A review of the literature revealed only 13 other reported cases. Brain-stem gangliogliomas usually become symptomatic in the first and second decades of life and involve the medulla and pons. Clinical improvement and prolonged survival have been reported after partial resection.
Choroid plexus cyst of the lateral ventricle in an elderly man
Authors: Hatashita Shizuo , Takagi Suguru , Sakakibara Tokiwa
Published: May 2009

✓ The authors report a case of a symptomatic choroid plexus cyst located in the right lateral ventricle of a 64-year-old man who presented with focal epilepsy. The cyst was diagnosed by computerized tomography, and was proven pathologically at surgery. Total removal was accomplished, with subsequent disappearance of the seizures. A brief review of the literature is included.
Percutaneous insertion of peritoneal shunt catheters with use of the Veress needle
Authors: Lockhart Curtis , Selman Warren , Rodziewicz Gerard , Spetzler Robert F.
Published: May 2009

✓ A safe percutaneous method of insertion of peritoneal shunt catheters is described. The method is based on the use of the Veress needle.
Surgical management of epilepsy using epidural recordings to localize the seizure focus
Authors: Goldring Sidney , Gregorie Erik M.
Published: May 2009

✓ One hundred patients with focal epilepsy (44 were children) were evaluated with extraoperative electrocorticography via epidural electrode arrays. Localization of the epileptogenic focus was derived predominantly from recordings made during spontaneously occurring seizures. All resection procedures were carried out under general anesthesia. During anesthesia, the recording of sensory evoked responses made it possible to readily identify the sensorimotor region. Of the 100 patients, 72 underwent resection of an epileptogenic focus, and 33 of these were children. Those who did not have a resection either exhibited a diffuse seizure focus, failed to show an electrical seizure discharge in association with the clinical seizure, failed to have a seizure during the period of monitoring, or failed to exhibit conclusive changes for identifying a focus in the interictal record. Fifty-seven patients (29 children and 28 adults) who had a resection have been followed for between 1 and 12 years. Eighteen (62%) of the 29 children and 18 (64%) of the 28 adults enjoyed a good result.

Twenty of the 100 patients reported here had temporal lobe epilepsy. They were candidates for recordings with depth electrodes to identify their focus, but they were evaluated instead with epidural recordings; the method is described. In 15 of them, a unilateral focus was identified and they underwent an anterior temporal lobectomy. Pathological changes were found in every case and, in 11 patients, the epidural recordings distinguished between a medial and a lateral focus. Ten of these patients have been followed for 9 months to 3½ years, and seven have had a good result. The observations suggest that epidural electrodes may be used in lieu of depth electrodes for identifying the symptomatic temporal lobe.
Supratentorial malignant gliomas of childhood
Authors: Phuphanich Surasak , Edwards Michael S. B. , Levin Victor A. , Vestnys Pamela S. , Wara William M. , Davis Richard L. , Wilson Charles B.
Published: May 2009

✓ Twenty-seven patients aged 1 to 18 years harboring supratentorial (20 in the cerebrum and seven in the thalamus) malignant gliomas were treated between 1975 and 1982. There were four glioblastomas multiforme, 14 anaplastic astrocytomas, and nine malignant gliomas. All patients had a subtotal resection or biopsy as the initial procedure and received postoperative radiation therapy (RT). Fifteen of 27 patients were treated by RT alone; 14 had tumor progression with a median time to tumor progression (MTP) of 65 weeks. Twelve patients were treated with chemotherapy as an adjuvant to RT; only seven had tumor recurrence, with an MTP of 130 weeks. Of the 21 patients with recurrent tumors in both groups, 18 were treated with chemotherapy alone, or chemotherapy with a second surgical procedure or second course of RT.

For all histological grades of tumor, the MTP for first recurrence was 75 weeks and the median survival time was 180 weeks. Age at initial diagnosis was found to be a statistically significant prognostic factor, with patients younger than 10 years of age surviving longer than patients aged over 10 years (p = 0.02).
Subselective preoperative embolization for meningiomas
Authors: Teasdale Evelyn , Patterson James , McLellan Douglas , Macpherson Peter
Published: May 2009

✓ Over a 2-year period the authors have studied the effects of preoperative subselective embolization of meningiomas. Thirty-six consecutive patients shown by computerized tomography (CT) to have a meningioma underwent selective internal and external carotid artery angiography, and any significant external carotid artery feeders were embolized (27 cases). It was found that CT and dynamic radioisotope scan findings were unable to predict the degree of vascularity of the tumor or its suitability for embolization. Furthermore, these tests, repeated after embolization, were unreliable in detecting either the extent of necrosis or reduction in blood flow. The effects of embolization upon surgery were recorded, and the excised tumor specimen examined for evidence of thrombosis and infarction. Subselective embolization was determined to be a simple, safe, and effective method of producing tumor necrosis and intraoperative hemostasis in selected patients.
Ultrastructural study of the formation of psammoma bodies in fibroblastic meningioma
Authors: Kubota Toshihiko , Sato Kazufumi , Yamamoto Shinjiro , Hirano Asao
Published: May 2009

✓ The fine structure of psammoma bodies was examined in four cases of fibroblastic meningioma. In general, large numbers of various-sized calcified bodies (psammoma bodies) were scattered among the interstitial fibers. In these bodies, the smallest calcific site was found in the extracellular membrane-bound matrix vesicles, which measured approximately 0.1 to 0.2 µ in diameter. In addition, extracellular “matrix giant bodies,” with or without hydroxyapatite aggregates and measuring up to 3 µ in diameter, were frequently encountered. These bodies were apparently invested with single, double, or multiple concentric walls averaging nearly 0.1 µ thick. They presumably originated from the neoplastic cells as a consequence of cytoplasmic residuals associated with cellular degeneration or necrotic cell processes. Hydroxyapatite crystals precipitated repeatedly within the bodies. The precipitate may gradually aggregate within the bodies, and gather in clusters, resulting in a large psammoma body. Finally, collagen fibers around the calcified giant bodies accrued deposits of apatite crystals to make a huge psammoma body. These findings suggest that both matrix giant bodies and matrix vesicles may serve as initial nidus of calcification of psammoma bodies in fibroblastic meningioma. Consequently, this mineralization process may represent a certain dystrophic calcification of meningocytic cells.
Morphological alterations of the degenerated lumbar disc following chemonucleolysis with chymopapain
Authors: Roggendorf Wolfgang , Brock Mario , Görge Hans-Hermann , Curio Gabriel
Published: May 2009

✓ Lumbar disc tissue from 10 patients who had previously undergone chemonucleolysis without success was studied by light and scanning electron microscopy. Seven patients had a sequestrated disc; three had large protrusions. As a control, material from 10 patients subjected to disc surgery without previous chemonucleolysis was studied in the same way. The control discs revealed the characteristic signs of degeneration: alteration of the collagen, microcystic areas, and giant chondromas. Changes following chemonucleolysis were restricted exclusively to the ground substance and characterized by a marked loss of basophilia in the cartilage matrix. There was no involvement of the anulus fibrosus, cartilage plate, or bone. Following chymopapain administration, scanning electron microscopy showed a naked collagen network devoid of ground substance.
Use of the argon surgical laser in neurosurgery
Authors: Powers Stephen K. , Edwards Michael S. B. , Boggan James E. , Pitts Lawrence H. , Gutin Philip H. , Hosobuchi Yoshio , Adams John E. , Wilson Charles B.
Published: May 2009

✓ The argon surgical laser has been used in 68 neurosurgical procedures that included the removal of intracranial and intraspinal tumors, spinal cord fenestration for syringomyelia, and the production of dorsal root entry zone lesions. Characteristics that make the argon surgical laser a useful microneurosurgical instrument include the availability of a fiberoptic delivery system, a laser spot size that can be varied continuously between 0.15 and 1.5 mm, a single laser-aiming and treatment beam, the transmission of argon laser light through aqueous media such as irrigating or cerebrospinal fluids, and improved hemostasis compared to conventional techniques. The argon laser is limited primarily by its relatively low power output (less than 16 W), which makes the excision of large tumors difficult. However, even with these limitations, which can be used to advantage in the proper setting, the authors' laboratory and clinical experience suggests that the argon surgical laser may be useful in certain microneurosurgical operations.
The Nd:YAG laser in neurosurgery
Authors: Wharen Robert E. , Anderson Robert E. , Scheithauer Bernd , Sundt Thoralf M.
Published: May 2009

✓ The biological response of normal cat brain to Nd:YAG laser light was studied both in vitro and in vivo to evaluate the potential safety of this laser for coagulation in brain tissue. Transmission studies revealed a blood:brain absorption ratio of 100:1 indicating the selective absorption of Nd:YAG light by hemoglobin and enabling Nd:YAG light to selectively heat blood vessels compared to brain tissue. In vivo temperature recordings and pathological evaluation demonstrated a remarkable ability of the brain to dissipate the thermal energy produced by Nd:YAG light with only a small amount of structural damage. Powers of 10 W applied for 8 seconds using a 1.2-mm focused probe resulted in a penetration depth in normal brain of only 2 mm. Thermal recordings also revealed that blood is heated to 90% of its maximum temperature within 3 seconds, while the brain temperature increases linearly as the duration of the laser pulse is increased. In addition, the localized heating of brain tissue was cooled rapidly within seconds following cessation of the laser pulse. These findings indicate that by using short, intermittent pulses of light focused upon blood vessels, damage to the surrounding tissue can be minimized, and the Nd:YAG laser can be used safely as an adjunctive measure for hemostasis in many neurosurgical procedures.
Measurements of brain-stem auditory evoked potentials in patients with spontaneous intracerebral hemorrhage
Authors: Lumenta Christianto B.
Published: May 2009

✓ Brain-stem auditory evoked potentials (BAEP's) were recorded in 19 patients with spontaneous intracerebral hemorrhage. More than half of the patients were deeply comatose. There was no correlation between BAEP changes and different types of spontaneous intracerebral hemorrhage or between BAEP's and coma grading by the Glasgow Coma Scale. However, BAEP's were a significant prognostic aid in these cases and useful in indicating the level of the brain-stem lesion.
Vertebrobasilar occlusion therapy of giant aneurysms
Authors: Pelz David M. , Viñuela Fernando , Fox Allan J. , Drake Charles G.
Published: May 2009

✓ The clinical and angiographic records were reviewed for 71 patients with giant aneurysms of the posterior circulation, who underwent therapeutic occlusion of the basilar artery or both vertebral arteries. This treatment is used when the aneurysm neck cannot be surgically clipped, and occlusion of the parent artery is performed to initiate thrombosis within the lumen. In these cases, collateral blood flow to the brain stem is supplied mainly by the posterior communicating arteries. Consequently, their angiographic morphology (patency, size, and number) is demonstrated as a preoperative indicator of whether the patient will be able to tolerate vertebrobasilar occlusion. Vertebral angiograms with carotid artery compression (the Allcock test) will often be needed to provide this information.

The data relating posterior communicating artery morphology to clinical outcome in 71 cases of attempted vertebrobasilar occlusion are presented. The use and accuracy of carotid artery compression studies are also discussed. It is essential for the radiologist to supply the neurosurgeon with this valuable information in every case of giant posterior circulation aneurysm.
Acute intracranial hypertension and brain-stem blood flow
Authors: Nagao Seigo , Sunami Norio , Tsutsui Takumi , Honma Yutaka , Momma Fumiyuki , Nishiura Tsukasa , Nishimoto Akira
Published: May 2009

✓ This study has been carried out to evaluate the effect of supratentorial mass lesions on the local cerebral blood flow (CBF) of the brain stem. Local CBF of the thalamus, inferior colliculus, and medulla oblongata, and supra- and infratentorial pressure were serially measured in 52 cats with intracranial hypertension produced by supratentorial balloon expansion. The mean control local CBF's in the thalamus, inferior colliculus, and medulla oblongata were 37.5, 42.1, and 30.7 ml/100 gm/min, respectively. At 20 to 30 mm Hg of supratentorial pressure, the local CBF of the thalamus started to decrease, and at 20 mm Hg of infratentorial pressure, the local CBF of the inferior colliculus began to decrease. Finally, at 40 to 60 mm Hg of infratentorial pressure, the local CBF of the medulla oblongata was affected. At the beginning of uncal herniation, indicated by anisocoria, the mean local CBF of the inferior colliculus abruptly decreased from 33.7 to 19.6 ml/100 gm/min in 16 cats. The Cushing response was evoked at a mean supratentorial pressure of 93.4 mm Hg and infratentorial pressure of 49.9 mm Hg in 16 cats. When the systemic arterial pressure was increased to the highest level in 13 cats, the mean local CBF of the medulla oblongata did not show significant change (a decrease from 22.8 to 20.9 ml/100 gm/min). The results suggest that at the beginning of uncal herniation, the local CBF of the upper brain stem markedly decreased. During the Cushing response, the local CBF of the medulla oblongata did not change significantly.
Anomalies of the posterior communicating artery and their potential clinical significance
Authors: Bisaria Krishna Kumar
Published: May 2009

✓ This study of the posterior communicating artery (PCoA) in 126 cranial cavities of adult cadavers revealed some hitherto unreported anomalies. These included: the origin of one PCoA from the ophthalmic artery inside the optic canal; the presence of three PCoA's on one side; the occurrence of two posterior cerebral arteries of different origin on one side; and the existence of junctional dilatations at both ends of a PCoA. Junctional dilatation at the commencement of the artery was seen in 6.3% of cases. More common anomalies were a fetal type of posterior cerebral artery in 31.7% and macroaneurysmal dilatation of the PCoA in 39.7% of cases. The presence of multiple arteries makes possible normal circulation in cases involving obstruction to any one of them. The junctional dilatation or dilatation of any other part of the PCoA, if pre-aneurysmal, may leak or rupture to produce subarachnoid hemorrhage. Arteries pressing on the oculomotor nerve may produce diplopia, and those compressing the optic chiasm and tracts may cause visual defects.
Intracerebral transplantation of a human glioma line in immunosuppressed rats
Authors: Saris Stephen C. , Bigner Sandra H. , Bigner Darell D.
Published: May 2009

✓ A model was developed for in vivo study of the human glioma-derived D-54 MG cell line in the brains of immunosuppressed Fischer 344 rats. The rats were injected with horse anti-rat thymocyte serum before and after intracerebral inoculation with 5 or 10 µl of a D-54 MG tumor cell suspension. Reproducible mortality distributions were obtained, with deaths occurring 18 to 34 days after intracerebral inoculation. Tumors grew as well circumscribed intracerebral masses with sheets of anaplastic cells, areas of necrosis bordered by concentrated nuclei, and minimal lymphocytic infiltration. Cytogenetic analysis revealed the same general chromosome distribution and markers in the heterotransplanted glioma cells as in the cultured line. Blood-brain barrier disruption was demonstrated by intracerebral tumor staining after intravenous injection of Evans blue dye. The in vivo growth of D-54 MG in immunosuppressed rats provides a reliable experimental model for the study of chemotherapy, immunodiagnosis, and immunotherapy of a human glioma-derived tumor in an animal sufficiently large to evaluate intracarotid or intratumoral injection of therapeutic agents.
Treatment of delayed radiation necrosis of the brain
Authors: Rizzoli Hugo V. , Pagnanelli David M.
Published: May 2009

✓ The authors report two cases of delayed radiation necrosis of the brain. In these cases a dramatic clinical and computerized tomographic improvement was noted after the institution of anticoagulant therapy. Based on a review of the literature, a possible causal mechanism is suggested. It was believed from both the clinical observation and the literature review that the anticoagulant agents had a direct effect upon the improvement in these patients. Laboratory data are needed to determine the role of anticoagulant therapy in the treatment of delayed radiation necrosis of the brain.
Spinal arachnoid cyst with unusual presentation
Authors: Spiegelmann Roberto , Rappaport Zvi Harry , Sahar Abraham
Published: May 2009

✓ A case is reported of spastic paraparesis due to a thoracic spinal arachnoid cyst. Symptoms occurred about 10 years after craniospinal injury. The histological examination revealed hemosiderin-containing macrophages trapped in the cyst wall. This finding and its possible pathogenetic implications are discussed, and the pertinent literature is reviewed.
Cortical artery aneurysm formation after extracranial to intracranial bypass surgery
Authors: Lantos George , Fein Jack M. , Knep Stanley
Published: May 2009

✓ An aneurysm of the recipient cortical artery developed 13 months after an extracranial-intracranial bypass procedure. A high transcranial pressure gradient between the scalp and the cortical arteries may have contributed to this unusual complication.
Pediatric neck injuries
Authors: Hill Stephen A. , Miller Carole A. , Kosnik Edward J. , Hunt William E.
Published: May 2009

✓ This review of pediatric neck injuries includes patients admitted to Children's Hospital of Columbus, Ohio, during the period 1969 to 1979. The 122 patients with neck injuries constituted 1.4% of the total neurosurgical admissions during this time. Forty-eight patients had cervical strains; 74 had involvement of the spinal column; and 27 had neurological deficits. The injuries reached their peak incidence during the summer months, with motor-vehicle accidents accounting for 31%, diving injuries and falls from a height 20% each, football injuries 8%, other sports 11%, and miscellaneous 10%.

There is a clear division of patients into a group aged 8 years or less with exclusively upper cervical injuries, and an older group with pancervical injuries. In the younger children, the injuries involved soft tissue (subluxation was seen more frequently than fracture), and tended to occur through subchondral growth plates, with a more reliable union than similar bone injuries. In the older children, the pattern and etiology of injury are the same as in adults. The entire cervical axis is at risk, and there is a tendency to fracture bone rather than cartilaginous structures.
Holographic investigation of the impact response of human heads
Authors: Dörheide Jürgen , Hoyer Heinz-E.
Published: May 2009

✓ The impact response of intact human cadaver heads was studied by means of double-pulsed holography using a ruby laser, and the transient deformation process at the surface of the skull was recorded. Frequency and acceleration measurements following impact were obtained. On frontal impact, the shock wave reached the opposite pole after 0.2 to 0.3 msec, and maximum amplitudes were found in the temporal regions. On impact to the vault, the deformation wave reached the skull base after 0.15 to 0.175 msec. Centers of maximum amplitude were recorded in the parietal and temporal regions. Deviations in the interference lines occurred at some sutures, revealing discontinuities. High-frequency components of the shock wave were demonstrated. The authors believe that fracture mechanisms may be elucidated by further studies of impact responses.
Somatosensory evoked potentials during spinal angiography and therapeutic transvascular embolization
Authors: Berenstein Alex , Young Wise , Ransohoff Joseph , Benjamin Vallo , Merkin Henry
Published: May 2009

✓ Somatosensory evoked potentials (SEP's) were monitored during 42 angiographic examinations and 33 therapeutic embolization procedures in 41 patients. The SEP amplitude decreased in 36 of the 42 angiographic techniques, but recovered to baseline within 2 to 4 minutes in all but one case. Angiographic opacification of the anterior spinal artery reduced SEP amplitude in all but two patients, who had lost their proprioceptive sense and had no recognizable SEP prior to the procedure. No neurological complications resulted from any of the angiography procedures. Of the 33 embolizations, 15 were performed in 12 patients with arteriovenous malformations (AVM's) and 18 in 17 patients with spinal canal tumors. There was only one complication associated with embolization: that occurred in a patient with an intramedullary spinal cord AVM. Monitoring SEP amplitude in this series of patients provided a means of rapidly and reliably identifying the anterior spinal artery, served to assess the potential risk of contemplated steps in embolization, and aided in the execution of the angiographic procedures.
Neurological outcome correlated with spinal evoked potentials in a spinal cord ischemia model
Authors: Cheng Man-Kai , Robertson Claudia , Grossman Robert G. , Foltz Richard , Williams Vick
Published: May 2009

✓ Occlusion of the abdominal aorta of the rabbit by inflating the balloon of a Swan-Ganz catheter positioned in the aorta is a simple and reliable method of producing spinal cord ischemia. The electrophysiological, neurological, and neuropathological correlates of ischemia with progressively longer durations and of ischemia after drug interventions were studied with the goal of developing an easily monitored, reproducible model for central nervous system ischemia. The percentage of animals developing paraplegia after varying periods of ischemia was zero after 15 minutes, 30% after 17 minutes, 33% after 20 minutes, 38% after 25 minutes, and 100% after 60 minutes of ischemia. After 25 minutes of ischemia the percentage of animals developing paraplegia was 87% when they were awake and not ventilated during ischemia and reperfusion, but dropped to 38% in animals that were paralyzed, sedated with ketamine, and ventilated, and when the metabolic acidosis that follows aortic occlusion was corrected during reperfusion. Pretreatment with thiopental, hypothermia, naloxone, methylprednisolone, and verapamil changed the percentage of animals developing paraplegia after 25 minutes of ischemia to 0%, 0%, 25%, 40%, and 100%, respectively. The component waves of the spinal somatosensory evoked potential (SSEP) disappeared sequentially during ischemia in the following order: P2, N4, N3, N2, and N1. After reperfusion, the SSEP components returned in reverse order of their disappearance. In the untreated animals, absence of the N3 wave for more than 10 minutes during ischemia was always followed by a neurological deficit. Pretreatment with thiopental or hypothermia permitted longer periods of electrophysiological silence without permanent neurological deficit. The ratio of the amplitude of N3 to N1 (N3/N1) was at least 70% of the control level, and N4 and P2 amplitudes were at least 30% of the control level at 120 minutes after reperfusion in all animals that had a normal outcome. Return of the N3/N1 amplitude to at least 90% of the control level or return of N3/N1 to 70% to 89% of control and P2 to at least 60% of control at 120 minutes after reperfusion reliably correlated with a normal 48-hour motor examination in animals with and without drug interventions.
Evaluation of the calcium channel antagonist nimodipine in experimental spinal cord ischemia
Authors: Faden Alan I. , Jacobs Thomas P. , Smith Michael T.
Published: May 2009

✓ The potent, centrally active, calcium channel antagonist, nimodipine, was utilized in a highly predictive “spinal stroke” model in order to investigate the potential pathophysiological effects of calcium flux in spinal injury, as well as to evaluate the potential therapeutic role of the newly developed dihydropyridine derivatives in ischemic central nervous system injury. Nimodipine, administered before or after ischemia, at doses shown to be effective in improving cerebral blood flow and in dilating central blood vessels, failed to improve either the histopathological changes or the functional deficit caused by temporary aortic occlusion in the unanesthetized rabbit.