bluuebunny/crossref_metadata_2025 huggingface dataset:
Cochlear nerve injuries caused by cerebellopontine angle manipulations
Authors: Sekiya Tetsuji , Møller Aage R.
Published: May 2009

✓ Changes in the response from the cochlear nerve in dogs resulting from cerebellopontine angle (CPA) manipulations were correlated with histological changes in the nerve. The aim of this study was to determine the mechanisms underlying hearing deficits incurred as a result of manipulations in the CPA. Compound action potentials (CAP) were recorded from the cochlear nerve in response to click stimulation before, during, and after cerebellar and eighth nerve retractions were performed under anesthesia. The retractions were carried out to elicit different degrees of change in the latency and waveform of the CAP. About 30 minutes after completion of the manipulations, the dogs were perfused with a fixative and their cochlear nerves and brain stems were prepared for histological studies. The results showed that retraction of the eighth nerve caused a disintegration of the myelin sheath, and there were multiple and extensive foci of petechial hemorrhage and thromboses of the vasa nervorum of the cochlear nerve.

In two dogs in which retraction was carried to a point at which the N2 peak of the CAP was abruptly obliterated, there was a separation of the central and peripheral myelin junction (Obersteiner-Redlich (OR) zone) and bleeding from the vasa nervorum at the OR zone. In the dogs in which the changes in the CAP had almost recovered before fixative perfusion, there were petechial hemorrhages within the cochlear nerve trunk, thus showing that improvement of electrophysiological responses may not always correlate with the absence of morphological changes.
Alpha-1-antitrypsin in human brain tumors
Authors: Sawaya Raymond , Zuccarello Mario , Highsmith Robert
Published: May 2009

✓ This study was undertaken to confirm the presence of alpha-1-antitrypsin (α1-AT) in human brain tumors and to attempt to elucidate its significance. Seventy-seven consecutive unselected patients with various brain tumors were entered in this study. Theα1-AT andα2-macroglobulin contents of the tumor extracts were qualitatively assessed by Ouchterlony immunodiffusion techniques. Plasminogen activator (PA) activity was assayed electrophoretically on sodium dodecyl sulfate gels. The patients were divided into two groups according to the positivity of their tumors toα1-AT. Sixty-eight percent of the tumors were positive forα1-AT, and all specimens were negative forα2-macroglobulin. Clinical and biological parameters obtained in all study patients failed to show statistically significant differences between the two groups with the exception of PA activity (p = 0.001), the peritumoral edema as seen on computerized tomography, and the preoperative serum fibrinogen level. These three parameters were higher in the group with specimens positive toα1-AT.

This study supports the hypothesis thatα1-AT is produced primarily by tumor cells in proportion to the regional proteolytic and inflammatory activity, and may protect the tumor cells.
Lumbosacral intersegmental epispinal axons and ectopic ventral nerve rootlets
Authors: Parke Wesley W. , Watanabe Ryo
Published: May 2009

✓ An epispinal system of motor axons virtually covers the ventral and lateral funiculi of the human conus medullaris between the L-2 and S-2 levels. These nerve fibers apparently arise from motor cells of the ventral horn nuclei and join spinal nerve roots caudal to their level of origin. In all observed spinal cords, many of these axons converged at the cord surface and formed an irregular group of ectopic rootlets that could be visually traced to join conventional spinal nerve roots at one to several segments inferior to their original segmental level; occasional rootlets joined a dorsal nerve root. As almost all previous reports of nerve root interconnections involved only the dorsal roots and have been cited to explain a lack of an absolute segmental sensory nerve distribution, it is believed that these intersegmental motor fibers may similarly explain a more diffuse efferent distribution than has previously been suspected.
Bursting pressure of experimental aneurysms
Authors: Quigley Matthew R. , Heiferman Kenneth , Kwaan Hau C. , Vidovich Danko , Nora Peter , Cerullo Leonard J.
Published: May 2009

✓ The laser-sealed arteriotomy (LSA) technique was used to create experimental aneurysms in the rat carotid artery. Animals were reexplored 2, 4, and 8 weeks following LSA, at which time the aneurysms were measured and subjected to a bursting strength pressure. In addition, a group of hypertensive rats with LSA was also tested 2 weeks after surgery. The LSA procedure produced aneurysms of a stable size and bursting pressure over the time studied. The bursting pressure technique may be applicable for assessing aneurysm therapy in an experimental setting.
Interhemispheric approach for carotid-ophthalmic artery aneurysm clipping
Authors: Aoki Nobuhiko
Published: May 2009

✓ The author reports a case in which a subchiasmal carotid-ophthalmic artery aneurysm was clipped through a bifrontal interhemispheric approach. This approach is feasible for carotid-ophthalmic artery aneurysms with a variety of anatomical correlations between the optic nerve and the aneurysmal neck.
Lipoma of the infundibulum
Authors: Esposito Stefano , Nardi Piervittorio
Published: May 2009

✓ Lipomas of the infundibulum are extremely rare and may not be recognized radiologically, even on computerized tomography (CT) scanning, if the tumor is less than 20 mm in diameter. A questionable CT diagnosis in the presence of endocrinological symptoms may justify an operation by microsurgical technique on the retrochiasmatic region. In the case reported, microsurgical removal of a small infundibular lipoma was successfully accomplished.
The risk of rebleeding from ruptured intracranial aneurysms
Authors: Rosenørn Jarl , Eskesen Vagn , Schmidt Kaare , Rønde Frits
Published: May 2009

✓ In the 5-year period from 1978 to 1983, 1076 patients with ruptured intracranial aneurysms were admitted to the six neurosurgical departments in Denmark and were entered in a prospective consecutive study conducted by the Danish Aneurysm Study Group. The patients were followed with 3-month and 2-year examinations or to death. A total of 133 patients suffered at least one rebleed after their initial hemorrhage during their first stay in the neurosurgical department; these patients had a mortality rate of 80% compared to 41 % for patients without a rebleed (p < 0.0001). During the first 2 weeks after the initial insult, 102 rebleeds were registered. The daily rate of rebleeds during these 2 weeks, calculated using a life-table method, varied from 0.2% to 2.1%. The rebleed rate during the first 24 hours (Day 0) was 0.8%, and the maximum risk of rebleeding was observed between Day 4 and Day 9. Significantly fewer rebleeds were reported in patients with good clinical grades (Grades 1 to 3, Hunt Grades I and II) compared to those with poor clinical grades (Grades 4 to 9, Hunt Grades III to V: p < 0.001).
Oxidative metabolism and glycolysis in benign brain tumors
Authors: Lichtor Terry , Dohrmann George J.
Published: May 2009

✓ Glucose utilization in vivo and hexokinase activity and mitochondrial oxygen consumption in vitro were measured in a series of human brain tumors. Several relatively slow-growing tumors appeared to have depressed electron-transport activities coupled with a compensatory elevated glucose utilization. These data suggest that a decrease in oxidative metabolism and a corresponding increase in glycolysis are not necessarily correlated with malignancy in certain human brain tumors.
Comparison of CT-guided and stereotaxic cranial diagnostic needle biopsies
Authors: Goldstein Simon , Gumerlock Mary Katherine , Neuwelt Edward A.
Published: May 2009

Needle biopsy of the brain utilizing computerized tomography (CT) scan data is an accepted diagnostic technique that has been performed both with and without the aid of stereotaxic frames. Experience with both techniques has resulted in a specific procedure for CT-guided free-hand biopsy which is performed in the CT suite under local anesthesia. Over the last 6 years the authors have performed 64 CT-guided free-hand biopsies and 13 stereotaxic biopsies with the Brown-Roberts-Wells system. Nonspecific gliosis, tumor, infection, radiation necrosis, or vascular malformation, were diagnosed in all but one biopsy, for a clinically accurate diagnostic yield of 92%. A comparison of diagnostic yield, morbidity, and mortality has shown no significant difference between the free-hand and the stereotaxic techniques. The time required for the procedures and their cost have been compared and have been found to be significantly less for the free-hand biopsy group. Thus, CT-guided free-hand biopsy may still represent the method of choice for histological diagnosis of many intracranial lesions.
Pressure-volume index as a function of cerebral perfusion pressure
Authors: Gray W. John , Rosner Michael J.
Published: May 2009

✓ The pressure-volume index (PVI) was measured in six adult cats while cerebral perfusion pressure (CPP) was reduced from normal levels to below the autoregulatory range by a continuous infusion of adenosine triphosphate. Anesthesia was induced with methohexital and maintained with an N2O:O2 (70%:30%) mixture. Body temperature, hematocrit, and PaCO2 were held constant throughout each experiment. Cerebral blood flow (CBF) was measured by the hydrogen clearance method. At CPP levels over 50 mm Hg, CBF remained relatively constant despite changes in CPP. Within this range, the PVI varied directly with CPP (PVI = 0.24 ml + 0.0013 mm Hg CPP). Below the autoregulatory range, CBF fell progressively with further decreases in CPP; in this range, PVI was found to increase as CPP fell (PVI = 0.84 ml − 0.0071 mm Hg CPP). These results indicate that the PVI is a complex function of CPP, varying directly with CPP within the autoregulatory range and indirectly with CPP below the autoregulatory range.
Effects of increased ICP on brain phosphocreatine and lactate determined by simultaneous 1H and 31P NMR spectroscopy
Authors: Sutton Leslie N. , McLaughlin Alan C. , Kemp William , Schnall M. D. , Cho Byung-Ku , Langfitt Thomas W. , Chance Britton
Published: May 2009

✓ In order to study the metabolic events surrounding ischemia induced by the graded increase of cerebrospinal fluid (CSF) pressure, the technique of simultaneous phosphorus-31- and hydrogen-1-enhanced nuclear magnetic resonance spectroscopy was applied to five cats as intracranial pressure (ICP) was gradually raised by the instillation of mock CSF. Threshold lactate rose at an average cerebral perfusion pressure (CPP) of 49 torr, and, in general, preceded a threshold decrease in phosphocreatine, which was observed at an average CPP of 29 torr. There was considerable variation among cats in the CPP at which failure of brain energy metabolism occurred, however, suggesting differences in the autoregulatory curves. It is concluded that, with elevated ICP, there is no universally “safe” CPP at which brain energy metabolism may be assumed to be uncompromised.
Digital angiographic quantification of blood flow dynamics in embolic stroke treated with tissue-type plasminogen activator
Authors: Kissel Phillip , Chehrazi Bahram , Seibert James A. , Wagner Franklin C.
Published: May 2009

✓ Computer analysis of digital subtraction angiography (DSA) was utilized to quantify the effectiveness of tissue-type plasminogen activator (TPA) in a rabbit cerebroembolic stroke model. Fourteen animals underwent cannulation of the facial artery and a preembolus angiogram. Autologous blood clots were then injected, and occlusion of the internal carotid artery at the circle of Willis was documented with repeat angiogram. The experimental group received a 1-mg/kg intravenous infusion of TPA via a femoral catheter for 90 minutes. A control group received an equivalent volume of saline. Follow-up angiograms were performed every 15 minutes. The TPA-treated animals showed progressive improvement in flow through previously occluded vessels. Time-density curves of the contrast material over the middle cerebral artery trunk and brain parenchyma were generated. The best integrated curves for the two groups were compared at 30 minutes after occlusion and 90 minutes after treatment. Animals were then observed for 24 hours and their neurological status was documented. Premortem infusion of either Evans blue dye or neutral red dye was performed and the integrity of the blood-brain barrier and tissue perfusion were assessed by video planometry. Significant improvements were noted by DSA, and Evans blue and neutral red dye studies in animals treated with TPA.
Immunohistochemical investigation of cerebral ischemia after middle cerebral artery occlusion in gerbils
Authors: Yamamoto Kazumi , Akai Fumiharu , Yoshimine Toshiki , Yanagihara Takehiko
Published: May 2009

✓ Progression and recovery of ischemic and postischemic damage after occlusion of the middle cerebral artery and subsequent reperfusion were investigated in the gerbil. This study was performed by immunohistochemical reaction testing for tubulin and creatine kinase BB-isoenzyme to visualize the neuronal structure and by immunohistochemical reaction testing for astroprotein (an astrocyte-specific protein) to visualize reactive astrocytes. The earliest ischemic lesion became visible in the frontoparietal cortex after 7 minutes of ischemia as a laminar loss of the reaction for tubulin involving the neuropil, neuronal perikarya, and dendrites. The earliest lesion in the caudoputamen evolved after 30 minutes of ischemia. After reestablishment of cerebral circulation, the immunohistochemical ischemic lesions in the neuronal structure disappeared if the ischemic period was 10 minutes or less and partially disappeared even after ischemia for 15 minutes in the cerebral cortex, while the postischemic lesion in the caudoputamen disappeared even after ischemia for 15 minutes. Reactive astrocytes were detected in the cerebral cortex and caudoputamen as early as 24 hours after reperfusion, both in the areas with and without the neuronal lesions. No lesion was identified in the hippocampus or thalamus. This experimental model is suitable for investigation of rapidly progressive regional ischemia in the cerebral cortex and for comparison with other regional or global cerebral ischemia in the gerbil or other animal species.
Effects of preexisting bypass graft on rCBF and SSEP's following acute stroke in dogs
Authors: Loftus Christopher M. , Silvidi Julius A. , Bernstein Daniel D. , Hitchon Patrick W. , Rosier Todd
Published: May 2009

✓ Regional cerebral blood flow (rCBF) was measured with radiolabeled microspheres in a canine model of superficial temporal artery-middle cerebral artery (STA-MCA) bypass and acute ischemia. Ischemic zone flows in seven dogs with the bypass first closed and then open showed no significant contribution of bypass flow in the intact vascular system. Following acute proximal occlusion, rCBF was preserved by bypass flow. A significant flow decrease ensued when the bypass was then clipped, confirming the adequacy of the lesion and the protective effect of the bypass. Reopening the bypass after 15 minutes of ischemia restored 76% of the previous flow. This was a significant increase from the global ischemia values, and was not statistically different from preocclusive values. Preocclusion somatosensory evoked potentials (SSEP's) in these animals showed a consistent biphasic wave at 8 to 10 msec after stimulation. This wave, with some decrease in amplitude, was preserved by bypass flow following creation of the arterial lesion. Bypass clipping abolished these ipsilateral SSEP's. Variable return of SSEP's occurred following reopening of the graft, but the recordings never reached preischemic amplitudes. This experimental study shows that, in this model, a prophylactic bypass subjected to immediate demand (with no time for “maturation”) can adequately augment cortical rCBF and is superior to delayed revascularization. The data lend theoretical support to placement of a prophylactic STA-MCA bypass prior to elective carotid artery sacrifice or in surgery where the risk of acute vascular injury is high.
Pathological and radiological correlation of subarachnoid hemorrhage in phencyclidine abuse
Authors: Boyko Orest B. , Burger Peter C. , Heinz E. Ralph
Published: May 2009

✓ Although hypertension can be associated with phencyclidine (PCP) use, subarachnoid hemorrhage (SAH) is a rare result. The radiological and pathological findings are reported of a patient with acute SAH who had chromatographic evidence of PCP in his blood. The occurrence of SAH in a patient who uses PCP may be caused by a disrupted arterial vessel wall and/or vasospasm due to the pharmacological action of the drug on the cerebral vasculature.
Spinal meningioma en plaque
Authors: Stechison Michael T. , Tasker Ronald R. , Wortzman George
Published: May 2009

✓ Two cases of spinal meningiomas exhibiting en plaque patterns of growth are presented, one of which is reviewed more fully with emphasis on the radiographic and histological characteristics. The difficulties in diagnosis of this unusual tumor, its surgical management, and its postoperative course are discussed.
Subtemporal-preauricular infratemporal fossa approach to large lateral and posterior cranial base neoplasms
Authors: Sekhar Laligam N. , Schramm Victor L. , Jones Neil F.
Published: May 2009

✓ A subtemporal-preauricular infratemporal fossa approach to remove 22 large neoplasms involving the lateral and posterior cranial base is detailed. The areas from which a neoplasm could be removed by this approach included the sphenoid and clival bone; the medial half of the petrous temporal bone; the infratemporal fossa; the nasopharynx; the retro- and parapharyngeal area; the ethmoid, sphenoid, and maxillary sinuses; and the intradural clivus-foramen magnum area. The pathology of the neoplasms included benign tumors such as meningioma, malignant cartilaginous neoplasms such as chordoma, and other malignant lesions such as nasopharyngeal carcinoma. This approach offers many advantages over other anterior and lateral approaches to the lateral and posterior cranial base: these include minimal brain retraction; direct access to the ipsilateral petrous and upper cervical internal carotid artery; reconstruction of extensive cranial base defects, often with the use of a vascularized rectus abdominis flap; preservation of the hearing conduction mechanism when it is not involved by tumor; and the maintenance of excellent facial nerve function postoperatively.

The use of an anterior extradural approach (transethmoidal) and of an intradural approach (frontotemporal or retromastoid), either concurrently or separately, is necessary in some patients to effect total tumor removal. The most serious complication in this series was the death of a patient due to postoperative infection and bilateral carotid artery rupture, which may have been avoided by the use of a rectus abdominis muscle flap for reconstruction. Among the 21 surviving patients, 18 had a good outcome, two had a fair outcome, and one with preexisting neurological deficits had a poor outcome. One of the surviving patients with a chordoma died of pulmonary metastases 1 year later, without evidence of local recurrence. The length of postoperative follow-up evaluation in these patients is insufficient to make any judgment about the effectiveness of this surgical approach in achieving a cure or long-term control of the tumors described.
Adjuvant high-dose photoradiation therapy in the treatment of cerebral glioma: a Phase 1–2 study
Authors: Kaye Andrew H. , Morstyn George , Brownbill David
Published: May 2009

✓ A Phase 1–2 study of high-dose photoradiation therapy was performed in 23 patients with cerebral tumors. Twenty-two patients had high-grade gliomas (13 glioblastomas, six recurrent glioblastomas, two anaplastic astrocytomas, and one recurrent anaplastic astrocytoma) and one had a right frontal metastasis from a carcinoma of the lung. Hematoporphyrin derivative was administered to these patients in a dose of 5 mg/kg and, 24 hours later, they all underwent a craniotomy with radical excision of the tumor. The tumor bed was then irradiated with 630 nm of laser light from either an argon dye laser or a gold metal vapor laser for between 43 and 94 minutes, receiving total doses of 70 to 120 J/sq cm (six cases) or 120 to 230 J/sq cm (17 cases). The temperature of the tumor bed was kept below 37°C by irrigation. Fifteen patients who developed new tumors underwent postoperative radiotherapy (45 Gy in 20 divided doses).

There was no evidence of increased cerebral edema and no other toxicity from the therapy. All patients were discharged from the hospital within 18 days of surgery. Four of seven patients with gliomas have suffered a further recurrence at 12 to 16 weeks, and two of 15 patients with primarily treated gliomas experienced recurrence at 3 and 13 months following therapy. Fifteen patients have had no recurrence of their tumor and are alive and well at a median follow-up period of 7 months (range 1 to 16 months). It is concluded that photoradiation therapy using 5 mg/kg of hematoporphyrin derivative and 630 nm light at doses of up to 230 J/sq cm can be used as an adjuvant to surgery and radiotherapy with no additional complications.
The MRI appearance of cavernous malformations (angiomas)
Authors: Rigamonti Daniele , Drayer Burton P. , Johnson Peter C. , Hadley Mark N. , Zabramski Joseph , Spetzler Robert F.
Published: May 2009

✓ The angiographic, computerized tomography (CT), and magnetic resonance imaging (MRI) findings were compared in 10 patients with a total of 16 pathologically verified cavernous angiomas. Only three lesions had abnormal vasculature in the form of venous pooling or a capillary blush. The CT scans were positive in seven patients and detected 14 lesions, while high-field strength (1.5 Tesla) MRI was positive in each case and demonstrated 27 distinct lesions. On T2-weighted MRI, the combination of a reticulated core of mixed signal intensity (SI) with a surrounding rim of decreased SI strongly suggests the diagnosis of a cavernous malformation. Smaller lesions appear as areas of decreased SI (black dots). The sensitivity of MRI is based on magnetic susceptibility and possibly diffusion effects related to field heterogeneity that is more conspicuous on high-field imaging and caused by the presence of excessive iron (hemosiderin).
The rCBF response to Diamox in normal subjects and cerebrovascular disease patients
Authors: Sullivan Humbert G. , Kingsbury Theodore B. , Morgan Mary E. , Jeffcoat Ronnie D. , Allison Jerry D. , Goode Jamie J. , McDonnell Dennis E.
Published: May 2009

✓ Age-related norms for the regional cerebral blood flow (rCBF) response to Diamox (acetazolamide) were based on studies of 55 normal subjects at rest and on studies of 33 of these 55 normal subjects following an intravenous injection of Diamox (22 mg/kg). After the Diamox injection, rCBF increased at all locations measured in all subjects. On average, rCBF increased 1.7 times. The following were found for rCBF in both resting and Diamox-treated subjects: 1) rCBF decreased significantly with increasing age; 2) slope and intercept for the regression of rCBF on age were largest for frontal detectors, intermediate for parietal detectors, and smallest for occipital detectors; 3) rCBF hyperfrontality was most noticeable in younger subjects; 4) in subjects of any age, 95% confidence intervals for rCBF were relatively large (expected value ± 30%) and lower 95% confidence intervals for Diamox rCBF tended to overlap the upper 95% confidence intervals for resting rCBF; and 5) side-to-side percentage difference in rCBF did not have a significant regression on age and tended to be less than 10% to 20%. Diamox did not have an important effect on blood pressure, pulse rate, or respiratory rate. The normative data for the rCBF response to Diamox was used in evaluating 20 patients with cerebrovascular disease. Forty percent of these patients, all of whom exhibited angiographic evidence of potentially hemodynamically significant lesions, had normal rCBF at rest and after Diamox injection. Twenty percent had normal resting flows with abnormal Diamox-activated flows. Asymmetry in rCBF was the most sensitive indicator of a potential abnormality in cerebral perfusion. Thirty percent of the abnormal studies showed only significant asymmetry. It is suggested that rCBF studies at rest and after Diamox treatment, with age-related norms, may be useful in the management of patients with cerebrovascular disease.
Effect of hypoxia on the contractile response to KCl, prostaglandin F2α, and hemoglobin
Authors: Nakagomi Tadayoshi , Kassell Neal F. , Sasaki Tomio , Fujiwara Shigeru , Lehman R. Michael , Johshita Hiroo , Torner James C.
Published: May 2009

✓ The purpose of this experiment was to evaluate the effect of hypoxia on thein vitrocontractile responses of canine basilar artery to KCl, prostaglandin (PG) F2α, and hemoglobin. Hypoxia was induced by changing the bubbling gas mixture in the chamber from 95% O2/5% CO2to 95% N2/5% CO2. Hypoxia augmented the contractile response developed at 95% O2to 25 mM and 50 mM KCl, 3 × 10−7M and 10−5M PGF2α, and 10−6M hemoglobin. No significant alteration of the hypoxic augmentation in any preparation exposed to 25 mM KCl, 3 × 10−7M PGF2α, or 10−6M hemoglobin was observed with guanethidine (10−5M), prazosin (10−5M), methysergide (10−5M), or diphenhydramine (10−5M).

Endothelial denudation did not affect hypoxic augmentation. Hypoxia did not cause any alteration of the contractile response to 10−6M PGF2αin Ca++-free media. Pretreatment with a calcium channel blocker, nicardipine, significantly inhibited the hypoxic potentiation of the contractile response to 25 mM KCl, 3 × 10−7M PGF2α, and 10−6M hemoglobin.

These results suggest that hypoxia augments the contractile response to these agonists by a direct action on the smooth-muscle cells, facilitating the transmembrane influx of extracellular calcium. Hypoxia of smooth-muscle cells in the major cerebral arteries might be involved in the pathogenesis of vasospasm.
Mineralization and biodegradation of CSF shunting systems
Authors: Echizenya Kouhei , Satoh Masaharu , Murai Hiroshi , Ueno Hiroo , Abe Hiroshi , Komai Takashi
Published: May 2009

✓ The mineralization and biodegradation of cerebrospinal fluid shunting systems were studied using material from 25 shunts that had been implanted for between 6 days and 10 years. New unused materials were also examined for comparison. Surface changes in six systems could be observed under an operating microscope. Substantial quantities of a white deposit had adhered to the tubing in four of the shunts. These changes were most advanced in the galeal penetrative portion of the shunts and are believed to have been caused by mechanical stress. Scanning electron microscopic analysis revealed surface wrinkles, microscopic holes, and tiny particles, suggesting deterioration of the material itself. An energy-dispersive analysis using x-rays demonstrated that the surface deposits were due to mineralization of calcium phosphate and that the tiny particle growth was aluminum. These changes may be a consequence of the degradation of silicone rubber. A discriminant analysis of the mineralization was carried out; thus, the age of the host and the duration of system implantation could be correlated with the incidence of mineralization (p < 0.1). A measurement of the physical properties showed progressive change with a remarkable deterioration in systems implanted for more than 5 years.
Arteriovenous malformation in moyamoya syndrome
Authors: Lichtor Terry , Mullan Sean
Published: May 2009

✓ Three patients are reported with the rare combination of moyamoya disease and features of an associated arteriovenous malformation. Two of the patients developed ischemic symptoms, and the third patient presented with an intracerebral hemorrhage. All three patients fit the criteria of a stage III moyamoya syndrome on the basis of the angiographic classification described by Suzuki and Takaku. The patients were referred to this medical center following angiography with the presumptive diagnosis of arteriovenous malformation.
Stump embolization from an occluded internal carotid artery
Authors: Ryan Patrick G. , Day Arthur L.
Published: May 2009

✓ A patient with known internal carotid artery occlusion developed transient ischemic attacks in the distribution of the occluded vessel. Arteriography demonstrated a thrombus clearly originating from the internal carotid artery stump, which was unassociated with significantly stenotic atherosclerotic disease of the ipsilateral common or external carotid arteries. Stump angioplasty and endarterectomy led to complete and sustained cessation of further symptoms.
Lymphomatoid granulomatosis apparently confined to one temporal lobe
Authors: Kerr Richard S. C. , Hughes J. T. , Blamires Trudi , Teddy Peter J.
Published: May 2009

✓ Lymphomatoid granulomatosis is of uncertain etiology and poses problems with diagnosis and treatment. A case with involvement of the right temporal lobe, but associated with cystoid macular edema of the retina, is described. The unusual mode of presentation, the radiographic, operative, and pathological findings, the response to surgery and radiotherapy, and the possible etiology are discussed.
Outcome after severe head injury
Authors: Alberico Anthony M. , Ward John D. , Choi Sung C. , Marmarou Anthony , Young Harold F.
Published: May 2009

✓ A consecutive series of 330 severely head-injured patients was studied prospectively. All of the patients were treated with the same protocols by the same physicians and staff in the same intensive care unit. All of the patients had intracranial pressure (ICP) monitoring. Of the 330 patients, 100 were in the pediatric age group (0 to 19 years of age) and 230 were in the adult group (20 to 80 years of age). Statistical analyses were performed with regard to outcome, Glasgow Coma Scale (GCS) score, ICP course, and incidence of surgical lesions. The average emergency room GCS score as well as the 24-hour GCS score for each group was the same. The percentage of patients having ICP that was normal, increased but reducible, and increased but not reducible in each group was the same.

The pediatric patients had a significantly higher percentage of good outcomes (43%) than the adult patients (28%) (p < 0.01). They also had a significantly lower mortality rate (24%) than the adult patients (45%) (p < 0.01). At 1 year following injury, 55% of pediatric patients had a good outcome compared to 21% of adults (p < 0.001); this trend was evident at 3 months, with the same p value. Pediatric patients with normal ICP had a higher percentage of good outcomes (70%) than the adult patients with normal ICP (48%) (p < 0.05). There was no significant difference in outcome in pediatric and adult patients with mass lesions or with increased ICP, regardless of whether or not the pressure was reducible. There was a much higher incidence of surgical mass lesions in adult patients (46%) than in pediatric patients (24%) (p < 0.001).
The effect of nutritional support on outcome from severe head injury
Authors: Young Byron , Ott Linda , Twyman Diana , Norton Jane , Rapp Robert , Tibbs Phillip , Haack Dennis , Brivins Brack , Dempsey Robert
Published: May 2009

✓ Fifty-one brain-injured patients with peak 24-hour admission Glasgow Coma Scale (GCS) scores of 4 to 10 were prospectively randomly assigned to receive total parenteral (TPN) or enteral (EN) nutrition. Patients were studied from hospital admission to 18 days postinjury. Outcome was assessed by the Glasgow Outcome Scale at 3 months, 6 months, and 1 year postinjury. The TPN group received a significantly higher cumulative mean intake of protein than the EN group (mean ± standard error of the mean: 1.35 ± 0.12 vs. 0.91 ± 0.9 gm/kg/day; p = 0.004). Mean cumulative caloric balance was also significantly higher in the TPN than in the EN group (75.6% ± 5.13% vs. 59% ± 4.26%; p = 0.02). Nitrogen balance was significantly more negative in the EN group during the 1st week postinjury (p = 0.002). The incidence of pneumonia, urinary tract infections, septic shock, and infections was not significantly different between groups. Classic nutritional assessment parameters such as anergy screens, total lymphocyte counts, and albumin levels were not significantly different between groups. The 11 patients in the EN group who did not tolerate tube feedings for 1 week postinjury had a significantly higher incidence of septic shock (p = 0.008). The change over time in GCS scores between groups was significantly different, with the TPN group showing a mean four-point increase in GCS score compared with a three-point increase in the EN group (p = 0.02). At 3 months the TPN group had a significantly higher percentage of favorable outcomes (43.5% vs. 17.9%, respectively; p = 0.05). At 6 months, 43.5% of the TPN group had a favorable outcome while 32.1% of the EN group had a favorable outcome (p = 0.29). By 1 year, 47.8% of the TPN group and 32.1% of the EN group had a favorable outcome (p = 0.20). In conclusion, more calories and protein usually can be administered to acute brain injury patients via the TPN route than by EN feedings via nasogastric or nasoduodenal routes. Traditional parameters for nutritional assessment are not useful in studying the efficacy of nutritional support during the first 2 weeks after head injury. Neurological recovery from head injury occurs more rapidly in patients with better early nutritional support.
Lesions in Meckel's cave: variable presentation and pathology
Authors: Beck David W. , Menezes Arnold H.
Published: May 2009

✓ A series of 12 patients with mass lesions arising from Meckel's cave is presented. Patients' age on presentation ranged from 13 months to 71 years. Nine of the 12 patients had symptoms referable to the fifth cranial nerve, but only three complained of facial pain. The 12 patients presented eight different pathological entities, including meningioma, lipoma, schwannoma, malignant melanotic schwannoma, arachnoid cyst, neurofibroma, epidermoid tumor, and chordoma. Computerized tomography and magnetic resonance imaging were most useful in localizing the lesion to Meckel's cave. All 12 patients underwent a subtemporal approach to the lesion, and gross total removal was achieved in 11. Postoperative results were excellent with no increased neurological deficits seen 3 months postoperatively. Most patients had resolution of the cranial nerve deficits except for fifth nerve function, which was impaired in nine patients postoperatively. This series demonstrates that lesions in Meckel's cave can have a varied and unusual presentation, as well as an assortment of pathology. Total removal of lesions in this area resulted in relief of symptoms in most patients, with minimum morbidity.
Collagen type III deficiency in patients with rupture of intracranial saccular aneurysms
Authors: Østergaard John R. , Oxlund Hans
Published: May 2009

✓ Samples of the middle cerebral artery (MCA) and the brachial artery were obtained post mortem from 14 patients who died following rupture of intracranial saccular aneurysms and from a control group of 14 age- and sex-matched patients who died of causes unrelated to aneurysm rupture. The biomechanical properties of ring-shaped arterial specimens were investigated by loading the specimens at a constant deformation rate until rupture. The relative amounts of collagen type I and type III were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) studies of cyanogen bromide peptides of collagen prepared from the arterial samples. A deficiency of collagen type III was demonstrated in specimens of the MCA in six of 14 patients with a ruptured intracranial saccular aneurysm. This deficiency was not accompanied by alterations in the mechanical arterial strength but resulted in a significant increase in the extensibility at stress values corresponding to blood pressures between 100 and 200 mm Hg. No difference was found between aneurysm patients and the control group in regard to the biomechanical properties of the brachial artery, despite the presence of a significant deficiency of collagen type III. The increase in vascular extensibility of the MCA may represent alterations in the fibrous structure and functional integrity of the cerebral arteries of aneurysm patients with collagen type III deficiency. Together with aggravating hemodynamic stresses, this deficiency may be an important factor in the pathogenesis of saccular aneurysms.
Effect of hypertension on small-vessel healing after microvascular anastomosis
Authors: Dernbach Paul D. , Myklebust Joel B. , Cusick Joseph F.
Published: May 2009

✓ Artery-to-artery microvascular anastomosis (MVA) has become an established therapeutic alternative for patients with giant intracranial aneurysms and other forms of cerebrovascular disease. Many patients afflicted with cerebrovascular disease also suffer from hypertension. To evaluate the effect of hypertension on healing of small arteries following MVA, 36 spontaneously hypertensive rats were subjected to end-to-side MVA of their common carotid arteries. At specific times after surgery the rats were sacrificed; the anastomotic site was removed and examined with light microscopy and scanning electron microscopy. All MVA's were patent, and there was no evidence of thrombus formation or stenosis at the operative site in any group. Also, there was no difference between the spontaneously hypertensive rats and the control normotensive rat group in the rate of endothelial coverage of the MVA. The presence of hypertension appears to have no effect on healing of small arteries in the rat.
Carotid artery mixing with diastole-phased pulsed drug infusion
Authors: Saris Stephen C. , Shook Daniel R. , Blasberg Ronald G. , Dedrick Robert L. , Doppman John L. , Bankiewicz Krzysztof S. , Blacklock J. Bob , Oldfield Edward H.
Published: May 2009

✓ Focal injury to the brain or retina is a frequent complication of drug delivery to the internal carotid artery (ICA) and may be due to poor mixing of the drug with blood at the infusion site. Rhesus monkeys were studied to determine whether phased drug delivery during diastole from a modified pulsatile angiographic injector would improve drug mixing in vivo. A radiolabeled flow tracer, carbon-14-iodoantipyrine (14C-IAP), was injected into the ICA of three monkeys in 80-msec pulses, each ending at least 50 msec before the end of local diastole. Local isotope concentration in the brain was determined by quantitative autoradiography. The ratio of highest to lowest concentration was 1.86 ± 0.26 (mean ± standard deviation) in the frontoparietal cortex, 1.65 ± 0.42 in the frontoparietal white matter, 1.89 ± 0.28 in the temporal cortex, and 1.39 ± 0.17 in the basal ganglia. These results were similar to recordings in three control animals that received intravenous 14C-IAP to demonstrate complete drug mixing ( 1.37 ± 0.12, 1.41 ± 0.11, 1.70 ± 0.08, 1.22 ± 0.24, respectively), and contrasted to findings in five animals which received continuous intracarotid infusions to demonstrate standard ICA drug delivery (4.54 ± 2.07, 2.94 ± 1.45, 5.43 ± 3.57, 3.60 ± 2.90, respectively). Pulsed intra-arterial infusion during diastole provides a technically simple method for improving intravascular drug mixing, and results in drug delivery to tissue capillaries that is proportional to blood flow.
Experimental intracerebral mass: time-related effects on local cerebral blood flow
Authors: Kingman Thomas A. , Mendelow A. David , Graham David I. , Teasdale Graham M.
Published: May 2009

✓ Cerebral blood flow (CBF) was measured at different times during the first 150 minutes following an experimental space-occupying lesion produced with a 50-µl microballoon in rats. Local CBF was measured with the carbon-14-labeled iodoantipyrine quantitative autoradiographic technique. A region of local ischemia developed around the mass, while the remote effects of the mass were minimal. The focal ischemic lesion enlarged with time, and simulated removal of the lesion within this design did not alleviate the ischemia.
Photochemically induced graded spinal cord infarction
Authors: Prado Ricardo , Dietrich W. Dalton , Watson Brant D. , Ginsberg Myron D. , Green Barth A.
Published: May 2009

✓ Neurological and morphological outcome was evaluated in a rat model of graded spinal cord infarction initiated by a photochemical reaction. In this model, light-dye interactions induce primary microvascular stasis, resulting in consistent patterns of tissue necrosis. Four groups of rats underwent photoinduction times ranging from 30 seconds to 10 minutes. Neurological and electrophysiological functions were assessed starting 1 week after irradiation and continuing for 8 weeks. A functional neurological score was obtained by combining results from sensory and motor tasks, and electrophysiological function was evaluated from the somatosensory evoked potential recordings. In rats irradiated for short periods (30 seconds and 1 minute) mild behavioral deficits were documented. In contrast, electrical conduction was suppressed acutely in both groups; this recovered by 8 weeks to baseline or near baseline in the 30-second group but not in the 1-minute group. In rats irradiated for longer periods (5 and 10 minutes), severe behavioral and conduction abnormalities were detected at both the subacute and chronic testing periods. Although no significant difference in behavior was documented between the 5- and 10-minute groups acutely, the rats with 5-minute photoinduction time demonstrated a significant improvement in behavior over time whereas the group with 10-minute photoinduction time showed no improvement. A severe conduction block was present in both animal groups during the course of the study. Histopathological examination combined with morphometric measurements of the lesion area in cross section revealed four different degrees of spinal cord necrosis which correlated significantly with photoinduction times and neurological scores at 8 weeks. Reproducible degrees of ischemic damage to spinal cord parenchyma following primary microvascular occlusion result in a predictable sequence of behavioral and functional abnormalities, which in some cases recover with time.
Bilateral anomalous course of the ulnar nerve at the wrist causing ulnar and median nerve compression syndrome
Authors: Galzio Renato J. , Magliani Vincenzo , Lucantoni Danilo , D'Arrigo Corrado
Published: May 2009

✓ The case of a patient with a bilateral compression syndrome of the ulnar and median nerves at the wrist is described. Both ulnar nerves, which were surgically explored at different times, followed an anomalous course and passed into the canalis carpi side by side with the median nerve. This variation in the course of the ulnar nerve is extremely rare and causes a unique syndrome with characteristic electromyographic patterns.
Symptomatic spinal epidural lipomatosis as a complication of steroid immunosuppression in cardiac transplant patients
Authors: Zampella Edward J. , Duvall Ernest R. , Sekar B. Chandra , Langford Keith H. , Epstein Andrew E. , Kirklin James K. , Morawetz Richard B.
Published: May 2009

✓ Patients with Cushing's syndrome may develop spinal epidural lipomatosis, an abnormal accumulation of fat in the spinal epidural space. This accumulation of fat may cause compression of the spinal cord or cauda equina with resulting neurological deficit. Two cases of symptomatic spinal lipomatosis are reported in cardiac transplant patients receiving chronic corticosteroid treatment. The literature is reviewed, and diagnostic and therapeutic considerations are discussed.
Short-term preoperative treatment of macroprolactinomas by dopamine agonists
Authors: Fahlbusch Rudolf , Buchfelder Michael , Schrell Uwe
Published: May 2009

✓ During a period of 3 years, 25 patients with intra- and extrasellar macroprolactinomas were pretreated with dopamine agonists for a period of 2 to 6½ weeks prior to transsphenoidal microsurgical tumor resection. Dopamine agonists were administered orally to 17 patients, intramuscularly to three patients, and both orally and intramuscularly to five patients. Repeated computerized tomography (CT) examinations revealed that all neoplasms except one cystic tumor were reduced in size during the course of dopamine-agonist administration. No complications attributable to medical pretreatment were observed. Tumor shrinkage increased the efficacy of surgery, especially in cases with considerable extrasellar extension of the adenomas. Within 3 months following adenomectomy, prolactin levels were adjusted to normal levels in 19 patients by additional low-dose treatment with dopamine agonists. Thin-collimation CT assessments performed at least 3 months after surgery showed no evidence of residual tumor tissue in 23 patients. It is concluded that administration of dopamine agonists for some weeks prior to surgery is a useful adjunct to transsphenoidal microsurgery for macroprolactinomas. The new injectable form of bromocriptine is particularly valuable for this purpose.
Prolactin-secreting adenomas: the preoperative response to bromocriptine treatment and surgical outcome
Authors: Hubbard Jerry L. , Scheithauer Bernd W. , Abboud Charles F. , Laws Edward R.
Published: May 2009

✓ Controversy exists regarding the effects of bromocriptine on the success of transsphenoidal surgery for patients with prolactinomas. Various studies on this drug have reported adverse effects, improvement, and no effect upon the subsequent surgical outcome. The authors have retrospectively reviewed the case histories of 55 patients with immunocytochemically confirmed prolactin-secreting pituitary adenomas operated on by a transsphenoidal approach between 1981 and 1985. All patients had received bromocriptine in a variety of doses and for variable durations prior to surgery.

Thirty-nine patients were women and 16 were men, with an age range of 8 to 72 years. Basal prolactin levels prior to bromocriptine treatment ranged from 38 to 100 ng/ml in 11 patients, from 101 to 200 ng/ml in 12, and greater than 200 ng/ml in 29. The “cure” rates were 54%, 58%, and 38%, respectively. Thirty-one patients had microadenomas, with a postoperative cure rate of 68%; 12 had diffuse expansive adenomas, with a 17% cure rate; and 12 had grossly invasive tumors, with a 17% cure rate. A response to preoperative bromocriptine therapy was defined as a return of the basal prolactin level to normal: 18 patients were responders and 29 were hyporesponders; in eight the data were not available. The postoperative cure rate was 50% for the responders and 31% for the hyporesponders. Taking into acount the distribution of tumor type, there was no actual difference in outcome between the responder and the hyporesponder groups. The total bromocriptine dose received preoperatively was nearly identical for all groups. No significant differences in the frequency or extent of fibrosis, calcification, or prolactin immunoreactivity were observed in the 55 patients when compared with 26 control prolactinomas not treated with bromocriptine. It is concluded that short-term bromocriptine treatment does not adversely affect surgical outcome in any of the prolactin-secreting adenoma groups, nor does response or lack of response to bromocriptine predict surgical outcome.